In order to understand the effects of cellular diffusion on the dynamic behaviors of cancer cell subpopulations,we establish a reaction-diffusion model of the competition between drug-sensitive and drug-resistant canc...In order to understand the effects of cellular diffusion on the dynamic behaviors of cancer cell subpopulations,we establish a reaction-diffusion model of the competition between drug-sensitive and drug-resistant cancer cells.Firstly,taking drug dosage and diffusion coefficients as bifurcation parameters,we investigate the Turing instability conditions for the drug-sensitive and drug-resistant cancer cell model driven by passive-diffusion and cross-diffusion factors at the positive steady state solution,and obtain the distribution regions of the model undergoing Turing instability.Secondly,we deduce the wave speed conditions for the three types of traveling wave solutions connecting two nontrivial steady state solutions,and prove the existence of traveling wave solutions driven by passive-diffusion,using the eigenvalue analysis method,the upper and lower solution method,and Schauder’s fixed point theorem.Finally,we perform some numerical simulations to verify the results of the obtained theories and give the spatially inhomogeneous steady state solutions and the traveling wave solutions,as well as the wave solutions of the non-uniformity diffusion with different temporal and spatial locations.展开更多
The rising prevalence of drug-resistant Gram-positive pathogens,particularly methicillin-resistant Staphy-lococcus aureus(MRSA)and vancomycin-resistant Enterococci(VRE),poses a substantial clinical challenge.Biofilm-a...The rising prevalence of drug-resistant Gram-positive pathogens,particularly methicillin-resistant Staphy-lococcus aureus(MRSA)and vancomycin-resistant Enterococci(VRE),poses a substantial clinical challenge.Biofilm-associated infections exacerbate this problem due to their inherent antibiotic resistance and complex structure.Current antibiotic treatments struggle to penetrate biofilms and eradicate persister cells,leading to prolonged antibiotic use and increased resistance.Host defense peptides(HDPs)have shown promise,but their clinical application is limited by factors such as enzymatic degradation and difficulty in largescale preparation.Synthetic HDP mimics,such as poly(2-oxazoline),have emerged as effective alter-natives.Herein,we found that the poly(2-oxazoline),Gly-POX_(20),demonstrated rapid and potent activity against clinically isolated multidrug-resistant Gram-positive strains.Gly-POX_(20) showed greater stability under physiological conditions compared to natural peptides,including resistance to protease degradation.Importantly,Gly-POX_(20) inhibited biofilm formation and eradicated mature biofilm and demonstrated superior in vivo therapeutic efficacy to vancomycin in a MRSA biofilm-associated mouse keratitis model,suggesting its potential as a novel antimicrobial agent against drug-resistant Gram-positive bacteria,especially biofilm-associated infections.展开更多
Antimicrobial resistance(AMR)is a growing public health crisis that requires innovative solutions.Emerging multidrug resistant(MDR)Salmonella typhimurium has raised concern for its effect on pathogenic infection and m...Antimicrobial resistance(AMR)is a growing public health crisis that requires innovative solutions.Emerging multidrug resistant(MDR)Salmonella typhimurium has raised concern for its effect on pathogenic infection and mortality in humans caused by enteric diseases.To combat these MDR Salmonella typhimurium pathogens,highly effective and broad-spectrum antibiotics such as flufenicol(FFC)need to be evaluated for their potent antibacterial activity against Salmonella typhimurium.However,the low solubility and low oral bioavailability of flufenicol need to be addressed to better combat AMR.In this work,we develop a novel nano-formulation,flufenicol nano-micelles(FTPPM),which are based on d-α-tocopherol polyethylene glycol 1,000 succinate(TPGS)/poloxamer 188(P188),for the targeted treatment of biofilms formed by drug-resistant Salmonella typhimurium in the intestine.Herein,FTPPM were prepared via a thin film hydration method.The preparation process for the mixed micelles is simple and convenient compared with other existing nanodrug delivery systems,which can further decrease production costs.The optimized FTPPM demonstrated outstanding stability and sustained release.An evaluation of the in vivo anti-drug-resistant Salmonella typhimurium efficacy demonstrated that FTPPM showed a stronger efficacy(68.17%)than did florfenicol-loaded TPGS polymer micelles(FTPM),flufenicol active pharmaceutical ingredients(FFC-API),and flufenicol commercially available medicine(FFC-CAM),and also exhibited outstanding biocompatibility.Notably,FTPPM also inhibited drug-resistant Salmonella typhimurium from forming biofilms.More importantly,FTPPM effectively restored intestinal flora disorders induced by drug-resistant Salmonella typhimurium in mice.In summary,FTPPM significantly improved the solubility and oral bioavailability of florfenicol,enhancing its efficacy against drug-resistant Salmonella typhimurium both in vitro and in vivo.FTPPM represent a promising drug-resistant Salmonella typhimurium treatment for curbing bacterial resistance via oral administration.展开更多
Objective Tuberculosis remains a severe public health issue, and the Beijing family of mycobacterium tuberculosis （M. tuberculosis） is widespread in East Asia, especially in some areas in China, like Beijing and Tia...Objective Tuberculosis remains a severe public health issue, and the Beijing family of mycobacterium tuberculosis （M. tuberculosis） is widespread in East Asia, especially in some areas in China, like Beijing and Tianjin. This study aimed at determining the mutation patterns of drug-resistant Beijing strains of M. tuberculosis isolated from Tianjin, China. Methods A total of 822 M. tuberculosis isolates were screened for drug resistance by an absolute concentration method and the genotype was identified by PCR. 169 drug-resistant isolates of the Beijing family were analyzed for the potential mutations in the rpoB, katG, inhA promoter region and in rpsL, rrs and embB genes, which are associated with resistance to rifampin （RFP）, isoniazid （INH）, streptomycin （SM） and ethambutol （EMB） respectively by PCR and DNA sequencing. Results Fifty-eight out of 63 RFP-resistant isolates were found to carry the mutations within the 81-bp RFP resistance determining region （RRDR） of the rpoB gene and the most frequent mutations occurred at codon 531 （44.4%）, 526 （28.6%）, and 516 （7.9%） respectively. 16 mutation pattems affecting 12 different codons around the RRDR of rpoB were found. Of 116 INH-resistant isolates, 56 （48.3%） had the mutation of katG 315 （AGC→ACC） （Ser→Thr）, 3 （2.6%） carried S315N （AGC→AAC） and 27 （16.0%） had the mutation of inhA-15A→T. 84 out of 122 SM-resistant isolates （68.9%） displayed mutations at the codons 43 or 88 with AAG→AGG （Lys→Arg） of the rpsL gene and 22 （18.0%） with the mutations at positions 513A→C, 516C→T or 905 A→G in the rrs gene. Of 34 EMB-resistant isolates, 6 had mutation with M306V （ATG→GTG）, 3 with M306I （ATG→ATT）, 1 with M306I （ATG→ATA）, 1 with D328Y （GAT→TAT）, 1 with V348L （GTC→CTC）, and 1 with G406S （GGC→AGC） in the embB gene. Conelusion These novel findings extended our understanding of resistance-related mutations in the Beijing strains of M. tuberculosis and may provide a scientific basis for development of new strategies for diagnosis and control of tuberculosis in China and other countries where Beijing strains are prevalent.展开更多
AIM: To evaluate the epidemiology and outcomes of culture-positive spontaneous bacterial peritonitis (SBP) and spontaneous bacteremia (SB) in decompensated cirrhosis.METHODS: We prospectively collected clinical, labor...AIM: To evaluate the epidemiology and outcomes of culture-positive spontaneous bacterial peritonitis (SBP) and spontaneous bacteremia (SB) in decompensated cirrhosis.METHODS: We prospectively collected clinical, laboratory characteristics, type of administered antibiotic, susceptibility and resistance of bacteria to antibiotics in one hundred thirty cases (68.5% males) with positive ascitic fluid and/or blood cultures during the period from January 1, 2012 to May 30, 2014. All patients with SBP had polymorphonuclear cell count in ascitic fluid > 250/mm<sup>3</sup>. In patients with SB a thorough study did not reveal any other cause of bacteremia. The patients were followed-up for a 30-d period following diagnosis of the infection. The final outcome of the patients was recorded in the end of follow-up and comparison among 3 groups of patients according to the pattern of drug resistance was performed.RESULTS: Gram-positive-cocci (GPC) were found in half of the cases. The most prevalent organisms in a descending order were Escherichia coli (33), Enterococcus spp (30), Streptococcus spp (25), Klebsiella pneumonia (16), S. aureus (8), Pseudomanas aeruginosa (5), other Gram-negative-bacteria (GNB) (11) and anaerobes (2). Overall, 20.8% of isolates were multidrug-resistant (MDR) and 10% extensively drug-resistant (XDR). Health-care-associated (HCA) and/or nosocomial infections were present in 100% of MDR/XDR and in 65.5% of non-DR cases. Meropenem was the empirically prescribed antibiotic in HCA/nosocomial infections showing a drug-resistance rate of 30.7% while third generation cephalosporins of 43.8%. Meropenem was ineffective on both XDR bacteria and Enterococcus faecium (E. faecium). All but one XDR were susceptible to colistin while all GPC (including E. faecium) and the 86% of GNB to tigecycline. Overall 30-d mortality was 37.7% (69.2% for XDR and 34.2% for the rest of the patients) (log rank, P = 0.015). In multivariate analysis, factors adversely affecting outcome included XDR infection (HR = 2.263, 95%CI: 1.005-5.095, P = 0.049), creatinine (HR = 1.125, 95%CI: 1.024-1.236, P = 0.015) and INR (HR =1.553, 95%CI: 1.106-2.180, P = 0.011).CONCLUSION: XDR bacteria are an independent life-threatening factor in SBP/SB. Strategies aiming at restricting antibiotic overuse and rapid identification of the responsible bacteria could help improve survival.展开更多
Oral antiviral agents have been developed in the last two decades for the treatment of chronic hepatitis B(CHB).However,antiviral resistance remains an important challenge for long-term CHB therapy.All of the clinical...Oral antiviral agents have been developed in the last two decades for the treatment of chronic hepatitis B(CHB).However,antiviral resistance remains an important challenge for long-term CHB therapy.All of the clinically available oral antiviral agents are nucleoside or nucleotide analogues that target the activity of viral reverse transcriptase(RT),and all are reported to have resistant mutations.Since the hepatitis B virus(HBV)RT,like other viral polymerases,lacks proofreading activity,the emergence of drug-resistance occurs readily under selective pressure from the administration of antiviral agents.The molecular diagnosis of drug-resistant HBV is based on sequence variations,and current diagnostic methods include sequencing,restriction fragment polymorphism analysis,and hybridization.Here,we will discuss the currently available molecular diagnosis tools,in vitro phenotypic assays for validation of drug-resistant HBV,and treatment options for drug-resistant HBV.展开更多
Objective To investigate distinctive features in drug-resistant mutations （DRMs） and interpretations for reverse transcriptase inhibitors （RTIs） between proviral DNA and paired viral RNA in HIV-l-infected patients...Objective To investigate distinctive features in drug-resistant mutations （DRMs） and interpretations for reverse transcriptase inhibitors （RTIs） between proviral DNA and paired viral RNA in HIV-l-infected patients. Methods Forty-three HIV-l-infected individuals receiving first-line antiretroviral therapy were recruited to participate in a multicenter AIDS Cohort Study in Anhui and Henan Provinces in China in 2004. Drug resistance genotyping was performed by bulk sequencing and deep sequencing on the plasma and whole blood of 77 samples, respectively. Drug-resistance interpretation was compared between viral RNA and paired proviral DNA. Results Compared with bulk sequencing, deep sequencing could detect more DRMs and samples with DRMs in both viral RNA and proviral DNA. The mutations M1841 and M2301 were more prevalent in proviral DNA than in viral RNA （Fisher＇s exact test, P〈0.05）. Considering ＇majority resistant variants＇, 15 samples （19.48%） showed differences in drug resistance interpretation between viral RNA and proviral DNA, and 5 of these samples with different DRMs between proviral DNA and paired viral RNA showed a higher level of drug resistance to the first-line drugs. Considering ＇minority resistant variants＇, 22 samples （28.57%） were associated with a higher level of drug resistance to the tested RTIs for proviral DNA when compared with paired viral RNA. Conclusion Compared with viral RNA, the distinctive information of DRMs and drug resistance interpretations for proviral DNA could be obtained by deep sequencing, which could provide more detailed and precise information for drug resistance monitoring and the rational design of optimal antiretroviral therapy regimens.展开更多
The infection and drug resistance rates of Helicobacter pylori(H.pylori)are high and must be prevented and treated by better strategies.Based on recent research advances in this field as well as the results from our t...The infection and drug resistance rates of Helicobacter pylori(H.pylori)are high and must be prevented and treated by better strategies.Based on recent research advances in this field as well as the results from our team and those on traditional Chinese medicine,we review the causes of drug resistance,and prevention and treatment strategies for drug-resistant H.pylori infection,with an aim to make suggestions for the development of new drugs,such as establishment of new target identification and screening systems,modification of existing drug structures,use of new technologies,application of natural products,and using a commercial compound library.This article may provide reference for eradication of drug-resistant H.pylori.展开更多
BACKGROUND Bedaquiline is among the prioritized drugs recommended by the World Health Organization for the treatment of extensively drug-resistant tuberculosis(XDRTB).Many patients have not achieved better clinical im...BACKGROUND Bedaquiline is among the prioritized drugs recommended by the World Health Organization for the treatment of extensively drug-resistant tuberculosis(XDRTB).Many patients have not achieved better clinical improvement after bedaquiline is stopped at 24 wk.However,there is no recommendation or guideline on bedaquiline administration beyond 24 wk,which is an important consideration when balancing the benefit of prognosis for XDR-TB against the uncertain safety concerning the newer antibiotics.CASE SUMMARY This paper reported 2 patients with XDR-TB(a female of 58 years of age and a female of 18 years of age)who received bedaquiline for 36 wk,as local experience to be shared.The 2 cases had negative cultures after 24 wk of treatment,but lung imaging was still positive.After discussion among experts,the consensus was made to bedaquiline prolongation by another 12 wk.The 36-wk prolonged use of bedaquiline in both cases achieved a favorable response without increasing the risk of cardiac events or new safety signals.CONCLUSION Longer regimen,including 36-wk bedaquiline treatment,might be an option for patients with XDR-TB.More studies are needed to explore the effectiveness and safety of prolonged use of bedaquiline for 36 wk vs standard 24 wk in the treatment of multidrug-resistant/XDR-TB or to investigate further the biomarkers and criteria indicative for extension of bedaquline to facilitate clinical use of thisnovel drug.展开更多
Background:Pentylenetetrazole kindling has long been used for the screening of investigational antiseizure drugs.The presence of lamotrigine,at a very low dose,does not hamper kindling in mice;rather it modifies this ...Background:Pentylenetetrazole kindling has long been used for the screening of investigational antiseizure drugs.The presence of lamotrigine,at a very low dose,does not hamper kindling in mice;rather it modifies this epileptogenesis process into drug-resistant epilepsy.The lamotrigine-pentylenetetrazole kindled mice show resistance to lamotrigine,phenytoin,and carbamazepine.It may also be possible that other licensed antiseizure drugs,like the mentioned drugs,remain ineffective in this model;therefore,this was the subject of this study.Methods:Swiss albino mice were kindled with pentylenetetrazole for 35 days in the presence of either methylcellulose vehicle or lamotrigine(subtherapeutic dose,ie,5 mg/kg).Vehicle vs lamotrigine-kindled mice were compared in terms of(a)resistance/response toward nine antiseizure drugs applied as monotherapies and two drug combinations;(b)lamotrigine bioavailability in blood and brain;(c)blood-brain barrier integrity;and(d)amino acids and monoamines in the cerebral cortex and hippocampus.Results:Lamotrigine vs vehicle-kindled mice are similar(or not significantly different P>.05 from each other)in terms of(a)response toward drug combinations;(b)lamotrigine bioavailability;and(c)blood-brain barrier integrity except for,significantly(P<.05)reduced taurine and increased glutamate in the cerebral cortex and hippocampus.Aside from these,lamotrigine-kindled mice show significant(P<.05)resistant to lamotrigine(15 mg/kg),levetiracetam(40 mg/kg);carbamazepine(40 mg/kg),zonisamide(100 mg/kg),gabapentin(224 mg/kg),pregabalin(30 mg/kg),phenytoin(35 mg/kg),and topiramate(300 mg/kg).Conclusion:Lamotrigine-pentylenetetrazole kindling takes longer to develop(~5 weeks)in comparison to lamotrigine-amygdale(~4 weeks)and lamotriginecorneal(~2 weeks)kindling models.However,drug screening through this model may yield superior drugs with novel antiseizure mechanisms.展开更多
BACKGROUND Pyogenic ventriculitis caused by extensively drug-resistant Acinetobacter baumannii(A.baumannii)is one of the most severe complications associated with craniotomy.However,limited therapeutic options exist f...BACKGROUND Pyogenic ventriculitis caused by extensively drug-resistant Acinetobacter baumannii(A.baumannii)is one of the most severe complications associated with craniotomy.However,limited therapeutic options exist for the treatment of A.baumannii ventriculitis due to the poor penetration rate of most antibiotics through the blood-brain barrier.CASE SUMMARY A 68-year-old male patient with severe traumatic brain injury developed pyogenic ventriculitis on postoperative day 24 caused by extensively drug-resistant A.baumannii susceptible to tigecycline only.Successful treatment was accomplished through multi-route administration of tigecycline,including intravenous combined with continuous ventricular irrigation plus intraventricular administration.The pus was cleared on the 3rd day post-irrigation,and cerebrospinal fluid cultures were negative after 12 d.CONCLUSION Our findings suggest that multi-route administration of tigecycline can be a therapeutic option against pyogenic ventriculitis caused by extensively drugresistant A.baumannii.展开更多
Listeria monocytogenes is the pathogen of listeriosis and it causes severe infections like septicemia, encephalitis, and meningitis, especially in immunocompromised individuals, newborns, and pregnant women. Its wide ...Listeria monocytogenes is the pathogen of listeriosis and it causes severe infections like septicemia, encephalitis, and meningitis, especially in immunocompromised individuals, newborns, and pregnant women. Its wide distribution in the environment and ability to survive or even grow under adverse conditions has made L. monocytogenes an important public health concern and in food industry.展开更多
Objective: Drug resistance is considered one of the main threats for tuberculosis control. Our aim was to identify risk factors for drug resistance in tuberculosis patients in the Northern Portugal. Study Design and M...Objective: Drug resistance is considered one of the main threats for tuberculosis control. Our aim was to identify risk factors for drug resistance in tuberculosis patients in the Northern Portugal. Study Design and Methods: Retrospective case-control study. The medical records and drug susceptibility test data from TB patients diagnosed between 31 March 2009 and 1 April 2010 were examined. We enrolled 119 patients with any drug resistance to first line anti-TB drugs and 238 with drug-susceptible TB, matched by age group. Variables analyzed included: gender, country of origin, employment situation, site of disease, previous treatment, presence of diabetes mellitus, HIV infection, alcohol abuse, intravenous drug use, abuse of other drugs and smoking habits. Multivariate conditional logistic regression was used to identify independent predictors for drug-resistant TB. Results: Diabetes mellitus [adjusted odds ratio (OR): 3.54;95% CI: 1.45 - 8.66], intravenous drug use (OR: 4.77;95% CI: 1.24 - 18.32) and previous TB treatment (OR: 2.48;95% CI: 1.12 - 5.49) were found to be risk factors for drug-resistant disease development. Conclusions: Diabetes mellitus, prior tuberculosis treatment, and intravenous drug use were risk factors for drug-resistant disease. The association between diabetes and drug-resistant TB should be further explored. Identifying clinical predictors of drug resistance can allow prompt identification of patients at risk for drug-resistant TB.展开更多
Background:Tuberculosis(TB),caused by Mycobacterium tuberculosis,remains the second leading cause of death from a single infectious disease globally and poses a significant economic and clinical burden in the world in...Background:Tuberculosis(TB),caused by Mycobacterium tuberculosis,remains the second leading cause of death from a single infectious disease globally and poses a significant economic and clinical burden in the world in 2022.Of particular concern is the emergence of drug-resistant TB,accounting for 15%-20%of TB deaths.It is imperative to delve into the global trends of incidence and death rate for multidrug-resistant tuberculosis(MDRTB)and extensively drug-resistant tuberculosis(XDR-TB),drawing upon the comprehensive Global Burden of Disease(GBD)2021 drug-resistant tuberculosis dataset.Methods:From the GBD 2021,data on incidence,prevalence,disability-adjusted life years(DALYs),and death of MDR-TB and XDR-TB from 1990 to 2021 were collected.We calculated the estimated annual percentage changes in age standardized incidence rate(ASIR)and age-standardized death rate(ASDR),segmented by age,sex,and socio-demographic index(SDI).The impacts of various risk factors on MDR-TB and XDR-TB were also analyzed.Results:In 2021,there were an estimated 443,680(95%uncertainty interval[UI]:259,196-766,545)incident cases of MDR-TB,and an estimated 106,818(95%UI:41,612-211,854)death cases of MDR-TB,while there were an estimated 24,036(95%UI:17,144-34,587)incident cases of XDR-TB and 7,946(95%UI:3,326-14,859)death cases of XDR-TB.The incidence and death cases of MDR-TB were lowest in high SDI regions,whereas the incidence rates of XDR-TB in high-middle SDI regions were higher than those in middle SDI and high SDI regions.Conclusion:This study reported the disease burden of drug-resistant TB from 1990 to 2021.Until 2021,drugresistant TB is still a serious problem in low SDI countries,especially for high-risk age populations with highrisk factors.Controlling drug-resistant TB requires effective control strategies and healthcare systems.展开更多
This study aimed to evaluate emerging trends of drug resistance to nucleoside reverse transcriptase inhibitors (NRTIs) and nonnucleoside reverse transcriptase inhibitors (NNRTIs) among 290 former blood donor HIV-1 inf...This study aimed to evaluate emerging trends of drug resistance to nucleoside reverse transcriptase inhibitors (NRTIs) and nonnucleoside reverse transcriptase inhibitors (NNRTIs) among 290 former blood donor HIV-1 infected patients in Hubei, China, from 2004 to 2006, all of whom had received anti-HIV-1 therapy. The presence of NRTI- and NNRTI-associated mutations were established by sequencing; genotypic and predicted phenotypic drug resistance were evaluated using HIVdb Program version 5.0.1 (http://hivdb.stanford.edu/ pages/algs/HIVdb.html). Genotypic drug resistance analysis showed significant increases in percentages of patients carrying HIV-1 strains with M41L, T215Y/F, D67N, K103N, G190A/S, Y181C/F or L210W mutations. Of the variants' predicted phenotypic drug resistance, highly significant increases were detected in percentages of patients carrying HIV-1 with high resistance to zidovudine (AZT) or stavudine (D4T) in NRTIs, and to delavirdine (DLV), efavirenz (EFV) or nevirapine (NVP) in NNRTIs; intermediate resistance to abacavir (ABC), AZT, D4T, didanosine (DDI) or tenofovir disoproxil fumarate (TDF) in NRTIs, and to etravirine (ETR) in NNRTIs; and low and potential low resistance to lamivudine (3TC), ABC, emtricitabine (FTC) or TDF in NRTIs, and to ETR in NNRTIs.展开更多
Introduction: The emergency of Mycobacterium tuberculosis resistant to the first line drug reduced access possibility to second line drugs for appropriate treatment and required for urgent action especially in le Demo...Introduction: The emergency of Mycobacterium tuberculosis resistant to the first line drug reduced access possibility to second line drugs for appropriate treatment and required for urgent action especially in le Democratic Republic of Congo (DRC), which counts among the highest tuberculosis (TB) burden countries in Africa. Objective: To present prevalence and describe multidrug-resistant tuberculosis cases in North-Kivu Province identified by using Genexpert technology. Methods: We conducted an observational prospective study on multidrug-resistant tuberculosis (MDR-TB) cases in North-Kivu Province, DRC from 2017 to 2018. All cases of MDR-TB identified by Genexpert MTB/ RIB were included in this series. Result: Of 15,544 tuberculosis cases registered during the study period, 19 cases of MDR-TB were identified. 57.9% was male, 89.5% was retreatment cases and 5.3% was coinfection HIV/TB cases. Conclusion: This new molecular technology diagnostic facilitates multidrug-resistance tuberculosis detection and improves the reporting of data lack.展开更多
There are various bacteria living in this world. The most common one is Staphylococcus aureus. Almost everyone has heard of it. It is easy to find their habitats, such as hospitals, homes, parks, schools etc. Some of ...There are various bacteria living in this world. The most common one is Staphylococcus aureus. Almost everyone has heard of it. It is easy to find their habitats, such as hospitals, homes, parks, schools etc. Some of them are difficult to be eliminated because of drug-resistant mutations. Hence, lots of researchers devoted their efforts to eliminate them. This review illustrates the characteristics of the Staphylococcus aureus and the main threat of their drug-resistant strains, especially methicillin-resistant S. aureus. What’s more, the article also highlights the plight in the drug development.展开更多
BACKGROUND Perampanel(PER),a third-generation antiepileptic drug,is a selective and noncompetitiveα-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor antagonist,and has been approved for the treatment of ad...BACKGROUND Perampanel(PER),a third-generation antiepileptic drug,is a selective and noncompetitiveα-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor antagonist,and has been approved for the treatment of adults and adolescents with focal epilepsy.However,there are only a few studies about the efficacy and tolerability of PER in young children with multidrug-resistant epilepsy.In this case,we aimed to share our clinical experience in this group.CASE SUMMARY A 4-year-old boy without perinatal asphyxia and familial history of epilepsy began to have ictal seizures from age 14 mo,with jerky movement of four limbs and head nodding.Abnormal multifocal discharge and background activity were recorded through electroencephalography,and no pathogenic mutation was found in the whole exome sequencing for the patient and his parents.He had received valproate,levetiracetam,topiramate,oxcarbazepine,clonazepam and lacosamide sequentially at different times,but he still had frequent seizures even after vagus nerve stimulation(VNS)implantation.He was diagnosed with idiopathic multidrug-resistant epilepsy.However,his seizure frequency was significantly reduced after PER administration in a dose-dependent manner,and better cognitive behavior was observed.In addition,the adverse reactions of anger and aggression also appeared.CONCLUSION PER is effective as add-on therapy for young children with multidrug-resistant epilepsy who have previously undergone VNS implantation.展开更多
Objectives: Bedaquiline (BDQ) is the first new anti-tuberculosis (TB) drug introduced to the market after 45 years. Recent studies have shown the potential benefits of adding bedaquiline to regimens for drug-resistant...Objectives: Bedaquiline (BDQ) is the first new anti-tuberculosis (TB) drug introduced to the market after 45 years. Recent studies have shown the potential benefits of adding bedaquiline to regimens for drug-resistant TB (DR-TB). In search of more effective regimens for DR-TB, bedaquiline was introduced in the TB program in the Philippines under operational research to assess its effectiveness, safety, and tolerability when given with background regimens among patients with multi-or extensively DR-TB (MDR/XDR-TB). Design: A prospective cohort study of patients with MDR/XDR-TB was given with a bedaquiline-containing regimen from June 2016 to May 2017. Demographic data, presence of comorbidities, and microbiologic profile on entry were recorded. Bedaquiline was administered at the recommended dose of 400 mg once daily for 14 days, then 200 mg three times a week for 22 weeks together with World Health Organization (WHO)-compliant background regimen. The time to culture conversion, interim outcomes at the 6th month of treatment, end-of-treatment outcomes, and post-treatment follow-up outcomes after one year was determined. The frequency and severity of adverse events (SAE) were recorded as part of pharmacovigilance. Results: Seventy-five patients were given with bedaquiline-containing regimen during the study period. Forty-two (56.0%) had second-line injectable resistance, 23 (30.7%) had fluoroquinolone-resistance, 6 (8.0%) had MDR-TB, and 4 (5.3%) had XDR-TB. In the 6th month of post-enrolment, 79% were culture-negative. The treatment success rate was 65.3% (37 were cured and 12 completed treatment), 7 (9.3%) died, 17 (22.7%) lost to follow-up, and 2 (2.7%) were withdrawn from treatment. Adverse events included vomiting (80%), dizziness (69%), nausea (52%), cough (44%), and headache (36%). The post-treatment follow-up of 49 patients in the 12th month showed 92% were culture-negative while 8% of TBC were not done. Conclusion: Bedaquiline-containing regimens for patients with MDR/XDR-TB were highly effective with an acceptable safety profile and favorable treatment outcomes, but the proportion of patients who lost to follow-up remains substantial.展开更多
Objective:To establish extensively drug-resistant Pseudomonas aeruginosa(XDR-PA)infection-induced pneumonia model in rats.Methods:Twenty-four male SD rats were randomly divided into blank group,low bacterial group,med...Objective:To establish extensively drug-resistant Pseudomonas aeruginosa(XDR-PA)infection-induced pneumonia model in rats.Methods:Twenty-four male SD rats were randomly divided into blank group,low bacterial group,medium bacterial group,and high bacterial group.The low,medium and high bacterial groups were given intratracheal instillation of 0.1 mL of bacterial suspension(bacterial concentration in turn is 7.5×10^(9),3×10^(10),6×10^(10)CFU/mL),while the blank group were given the same volume of sterile normal saline.After modeling,the general conditions of rats in each group were observed,including mental state,hair,respiration,activity,eating,weight,and the survival curve was drawn.The pathological characteristics of lung tissue and the infiltration of inflammatory cells were observed.Pathogenic identification of each group was carried out by bacterial culture of lung tissue homogenate.Results:The general state of the blank group was normal,and the rats in other groups showed signs of mental depression,bristling,shortness of breath,even oral and nasal bleeding,decreased food intake and activity,and significant weight loss,and different degrees of death within 48 hours,the difference was statistically significant(P<0.05).Pathological results showed that the alveolar structure of rats in the blank group was complete,and the alveolar space was clear without exudation.The lung tissue of the low and medium bacterial groups showed obvious inflammatory cell infiltration,alveolar structure destruction,alveolar septum thickening,interstitial edema,but the pathological damage of the medium group was more severe,with a mortality rate of up to 50%,and the mortality rate of the low bacterial group was 17%.In the high bacterial group,red blood cells,inflammatory cells and a large amount of fibrin-like exudation can be seen in the alveolar space,which has the pathological characteristics of acute respiratory failure,and the mortality rate is as high as 67%.The results of bacterial culture of lung tissue homogenate showed that the blank group had no bacterial colonies,while PA colony growth can be seen in low,medium and high bacterial groups.Conclusion:9 Intratracheal instillation of low bacterial count(0.1 mL of 7.5×10^(9) CFU/mL)XDR-PA bacterial suspension can successfully construct a rat pneumonia model of XDR-PA infection.展开更多
文摘In order to understand the effects of cellular diffusion on the dynamic behaviors of cancer cell subpopulations,we establish a reaction-diffusion model of the competition between drug-sensitive and drug-resistant cancer cells.Firstly,taking drug dosage and diffusion coefficients as bifurcation parameters,we investigate the Turing instability conditions for the drug-sensitive and drug-resistant cancer cell model driven by passive-diffusion and cross-diffusion factors at the positive steady state solution,and obtain the distribution regions of the model undergoing Turing instability.Secondly,we deduce the wave speed conditions for the three types of traveling wave solutions connecting two nontrivial steady state solutions,and prove the existence of traveling wave solutions driven by passive-diffusion,using the eigenvalue analysis method,the upper and lower solution method,and Schauder’s fixed point theorem.Finally,we perform some numerical simulations to verify the results of the obtained theories and give the spatially inhomogeneous steady state solutions and the traveling wave solutions,as well as the wave solutions of the non-uniformity diffusion with different temporal and spatial locations.
基金financially supported by the National Key Research and Development Program of China(no.2022YFC2303100)National Natural Science Foundation of China(nos.T2325010,22305082,52203162,and 22075078)+1 种基金Shanghai Frontiers Science Center of Optogenetic Techniques for Cell Metabolism(Shanghai Municipal Education Commission),the Fundamental Research Funds for the Central Universities(nos.JKVD1241029 and JKD01241701)Open Research Fund of State Key Laboratory of Polymer Physics and Chemistry(Changchun Institute of Applied Chemistry,Chinese Academy of Sciences),the Open Project of Engineering Research Center of Dairy Quality and Safety Control Technology(Ministry of Education,no.R202201).
文摘The rising prevalence of drug-resistant Gram-positive pathogens,particularly methicillin-resistant Staphy-lococcus aureus(MRSA)and vancomycin-resistant Enterococci(VRE),poses a substantial clinical challenge.Biofilm-associated infections exacerbate this problem due to their inherent antibiotic resistance and complex structure.Current antibiotic treatments struggle to penetrate biofilms and eradicate persister cells,leading to prolonged antibiotic use and increased resistance.Host defense peptides(HDPs)have shown promise,but their clinical application is limited by factors such as enzymatic degradation and difficulty in largescale preparation.Synthetic HDP mimics,such as poly(2-oxazoline),have emerged as effective alter-natives.Herein,we found that the poly(2-oxazoline),Gly-POX_(20),demonstrated rapid and potent activity against clinically isolated multidrug-resistant Gram-positive strains.Gly-POX_(20) showed greater stability under physiological conditions compared to natural peptides,including resistance to protease degradation.Importantly,Gly-POX_(20) inhibited biofilm formation and eradicated mature biofilm and demonstrated superior in vivo therapeutic efficacy to vancomycin in a MRSA biofilm-associated mouse keratitis model,suggesting its potential as a novel antimicrobial agent against drug-resistant Gram-positive bacteria,especially biofilm-associated infections.
基金supported by the grants from the National Key Research and Development Program of China(Grant No.:2024YFE0106300)the Key Projects of Natural Science Foundation of Anhui Provincial Department of Education,China(Grant No.:2023AH051017)+2 种基金the Outstanding Youth Scientific Research Foundation of the Anhui Education Department,China(Grant No.:2024AH030019)the National Natural Science Foundation of China(Grant No.:32302923)Natural Science Foundation of Anhui Province,China(Grant No.:2208085MC79).
文摘Antimicrobial resistance(AMR)is a growing public health crisis that requires innovative solutions.Emerging multidrug resistant(MDR)Salmonella typhimurium has raised concern for its effect on pathogenic infection and mortality in humans caused by enteric diseases.To combat these MDR Salmonella typhimurium pathogens,highly effective and broad-spectrum antibiotics such as flufenicol(FFC)need to be evaluated for their potent antibacterial activity against Salmonella typhimurium.However,the low solubility and low oral bioavailability of flufenicol need to be addressed to better combat AMR.In this work,we develop a novel nano-formulation,flufenicol nano-micelles(FTPPM),which are based on d-α-tocopherol polyethylene glycol 1,000 succinate(TPGS)/poloxamer 188(P188),for the targeted treatment of biofilms formed by drug-resistant Salmonella typhimurium in the intestine.Herein,FTPPM were prepared via a thin film hydration method.The preparation process for the mixed micelles is simple and convenient compared with other existing nanodrug delivery systems,which can further decrease production costs.The optimized FTPPM demonstrated outstanding stability and sustained release.An evaluation of the in vivo anti-drug-resistant Salmonella typhimurium efficacy demonstrated that FTPPM showed a stronger efficacy(68.17%)than did florfenicol-loaded TPGS polymer micelles(FTPM),flufenicol active pharmaceutical ingredients(FFC-API),and flufenicol commercially available medicine(FFC-CAM),and also exhibited outstanding biocompatibility.Notably,FTPPM also inhibited drug-resistant Salmonella typhimurium from forming biofilms.More importantly,FTPPM effectively restored intestinal flora disorders induced by drug-resistant Salmonella typhimurium in mice.In summary,FTPPM significantly improved the solubility and oral bioavailability of florfenicol,enhancing its efficacy against drug-resistant Salmonella typhimurium both in vitro and in vivo.FTPPM represent a promising drug-resistant Salmonella typhimurium treatment for curbing bacterial resistance via oral administration.
基金supported by National Science Key Grant(2008ZX10003-009).
文摘Objective Tuberculosis remains a severe public health issue, and the Beijing family of mycobacterium tuberculosis （M. tuberculosis） is widespread in East Asia, especially in some areas in China, like Beijing and Tianjin. This study aimed at determining the mutation patterns of drug-resistant Beijing strains of M. tuberculosis isolated from Tianjin, China. Methods A total of 822 M. tuberculosis isolates were screened for drug resistance by an absolute concentration method and the genotype was identified by PCR. 169 drug-resistant isolates of the Beijing family were analyzed for the potential mutations in the rpoB, katG, inhA promoter region and in rpsL, rrs and embB genes, which are associated with resistance to rifampin （RFP）, isoniazid （INH）, streptomycin （SM） and ethambutol （EMB） respectively by PCR and DNA sequencing. Results Fifty-eight out of 63 RFP-resistant isolates were found to carry the mutations within the 81-bp RFP resistance determining region （RRDR） of the rpoB gene and the most frequent mutations occurred at codon 531 （44.4%）, 526 （28.6%）, and 516 （7.9%） respectively. 16 mutation pattems affecting 12 different codons around the RRDR of rpoB were found. Of 116 INH-resistant isolates, 56 （48.3%） had the mutation of katG 315 （AGC→ACC） （Ser→Thr）, 3 （2.6%） carried S315N （AGC→AAC） and 27 （16.0%） had the mutation of inhA-15A→T. 84 out of 122 SM-resistant isolates （68.9%） displayed mutations at the codons 43 or 88 with AAG→AGG （Lys→Arg） of the rpsL gene and 22 （18.0%） with the mutations at positions 513A→C, 516C→T or 905 A→G in the rrs gene. Of 34 EMB-resistant isolates, 6 had mutation with M306V （ATG→GTG）, 3 with M306I （ATG→ATT）, 1 with M306I （ATG→ATA）, 1 with D328Y （GAT→TAT）, 1 with V348L （GTC→CTC）, and 1 with G406S （GGC→AGC） in the embB gene. Conelusion These novel findings extended our understanding of resistance-related mutations in the Beijing strains of M. tuberculosis and may provide a scientific basis for development of new strategies for diagnosis and control of tuberculosis in China and other countries where Beijing strains are prevalent.
文摘AIM: To evaluate the epidemiology and outcomes of culture-positive spontaneous bacterial peritonitis (SBP) and spontaneous bacteremia (SB) in decompensated cirrhosis.METHODS: We prospectively collected clinical, laboratory characteristics, type of administered antibiotic, susceptibility and resistance of bacteria to antibiotics in one hundred thirty cases (68.5% males) with positive ascitic fluid and/or blood cultures during the period from January 1, 2012 to May 30, 2014. All patients with SBP had polymorphonuclear cell count in ascitic fluid > 250/mm<sup>3</sup>. In patients with SB a thorough study did not reveal any other cause of bacteremia. The patients were followed-up for a 30-d period following diagnosis of the infection. The final outcome of the patients was recorded in the end of follow-up and comparison among 3 groups of patients according to the pattern of drug resistance was performed.RESULTS: Gram-positive-cocci (GPC) were found in half of the cases. The most prevalent organisms in a descending order were Escherichia coli (33), Enterococcus spp (30), Streptococcus spp (25), Klebsiella pneumonia (16), S. aureus (8), Pseudomanas aeruginosa (5), other Gram-negative-bacteria (GNB) (11) and anaerobes (2). Overall, 20.8% of isolates were multidrug-resistant (MDR) and 10% extensively drug-resistant (XDR). Health-care-associated (HCA) and/or nosocomial infections were present in 100% of MDR/XDR and in 65.5% of non-DR cases. Meropenem was the empirically prescribed antibiotic in HCA/nosocomial infections showing a drug-resistance rate of 30.7% while third generation cephalosporins of 43.8%. Meropenem was ineffective on both XDR bacteria and Enterococcus faecium (E. faecium). All but one XDR were susceptible to colistin while all GPC (including E. faecium) and the 86% of GNB to tigecycline. Overall 30-d mortality was 37.7% (69.2% for XDR and 34.2% for the rest of the patients) (log rank, P = 0.015). In multivariate analysis, factors adversely affecting outcome included XDR infection (HR = 2.263, 95%CI: 1.005-5.095, P = 0.049), creatinine (HR = 1.125, 95%CI: 1.024-1.236, P = 0.015) and INR (HR =1.553, 95%CI: 1.106-2.180, P = 0.011).CONCLUSION: XDR bacteria are an independent life-threatening factor in SBP/SB. Strategies aiming at restricting antibiotic overuse and rapid identification of the responsible bacteria could help improve survival.
文摘Oral antiviral agents have been developed in the last two decades for the treatment of chronic hepatitis B(CHB).However,antiviral resistance remains an important challenge for long-term CHB therapy.All of the clinically available oral antiviral agents are nucleoside or nucleotide analogues that target the activity of viral reverse transcriptase(RT),and all are reported to have resistant mutations.Since the hepatitis B virus(HBV)RT,like other viral polymerases,lacks proofreading activity,the emergence of drug-resistance occurs readily under selective pressure from the administration of antiviral agents.The molecular diagnosis of drug-resistant HBV is based on sequence variations,and current diagnostic methods include sequencing,restriction fragment polymorphism analysis,and hybridization.Here,we will discuss the currently available molecular diagnosis tools,in vitro phenotypic assays for validation of drug-resistant HBV,and treatment options for drug-resistant HBV.
基金supported by grants from the State Key Laboratory of Infectious Disease Prevention and Control(2011SKLID102)the National Nature Science Foundation of China(81172733 and 81561128006)the 12th Five-Year National Science and Technology Major Project(2013ZX10001-006)
文摘Objective To investigate distinctive features in drug-resistant mutations （DRMs） and interpretations for reverse transcriptase inhibitors （RTIs） between proviral DNA and paired viral RNA in HIV-l-infected patients. Methods Forty-three HIV-l-infected individuals receiving first-line antiretroviral therapy were recruited to participate in a multicenter AIDS Cohort Study in Anhui and Henan Provinces in China in 2004. Drug resistance genotyping was performed by bulk sequencing and deep sequencing on the plasma and whole blood of 77 samples, respectively. Drug-resistance interpretation was compared between viral RNA and paired proviral DNA. Results Compared with bulk sequencing, deep sequencing could detect more DRMs and samples with DRMs in both viral RNA and proviral DNA. The mutations M1841 and M2301 were more prevalent in proviral DNA than in viral RNA （Fisher＇s exact test, P〈0.05）. Considering ＇majority resistant variants＇, 15 samples （19.48%） showed differences in drug resistance interpretation between viral RNA and proviral DNA, and 5 of these samples with different DRMs between proviral DNA and paired viral RNA showed a higher level of drug resistance to the first-line drugs. Considering ＇minority resistant variants＇, 22 samples （28.57%） were associated with a higher level of drug resistance to the tested RTIs for proviral DNA when compared with paired viral RNA. Conclusion Compared with viral RNA, the distinctive information of DRMs and drug resistance interpretations for proviral DNA could be obtained by deep sequencing, which could provide more detailed and precise information for drug resistance monitoring and the rational design of optimal antiretroviral therapy regimens.
基金Supported by National Natural Science Foundation of China,No.81760739 and No.31460023.
文摘The infection and drug resistance rates of Helicobacter pylori(H.pylori)are high and must be prevented and treated by better strategies.Based on recent research advances in this field as well as the results from our team and those on traditional Chinese medicine,we review the causes of drug resistance,and prevention and treatment strategies for drug-resistant H.pylori infection,with an aim to make suggestions for the development of new drugs,such as establishment of new target identification and screening systems,modification of existing drug structures,use of new technologies,application of natural products,and using a commercial compound library.This article may provide reference for eradication of drug-resistant H.pylori.
文摘BACKGROUND Bedaquiline is among the prioritized drugs recommended by the World Health Organization for the treatment of extensively drug-resistant tuberculosis(XDRTB).Many patients have not achieved better clinical improvement after bedaquiline is stopped at 24 wk.However,there is no recommendation or guideline on bedaquiline administration beyond 24 wk,which is an important consideration when balancing the benefit of prognosis for XDR-TB against the uncertain safety concerning the newer antibiotics.CASE SUMMARY This paper reported 2 patients with XDR-TB(a female of 58 years of age and a female of 18 years of age)who received bedaquiline for 36 wk,as local experience to be shared.The 2 cases had negative cultures after 24 wk of treatment,but lung imaging was still positive.After discussion among experts,the consensus was made to bedaquiline prolongation by another 12 wk.The 36-wk prolonged use of bedaquiline in both cases achieved a favorable response without increasing the risk of cardiac events or new safety signals.CONCLUSION Longer regimen,including 36-wk bedaquiline treatment,might be an option for patients with XDR-TB.More studies are needed to explore the effectiveness and safety of prolonged use of bedaquiline for 36 wk vs standard 24 wk in the treatment of multidrug-resistant/XDR-TB or to investigate further the biomarkers and criteria indicative for extension of bedaquline to facilitate clinical use of thisnovel drug.
文摘Background:Pentylenetetrazole kindling has long been used for the screening of investigational antiseizure drugs.The presence of lamotrigine,at a very low dose,does not hamper kindling in mice;rather it modifies this epileptogenesis process into drug-resistant epilepsy.The lamotrigine-pentylenetetrazole kindled mice show resistance to lamotrigine,phenytoin,and carbamazepine.It may also be possible that other licensed antiseizure drugs,like the mentioned drugs,remain ineffective in this model;therefore,this was the subject of this study.Methods:Swiss albino mice were kindled with pentylenetetrazole for 35 days in the presence of either methylcellulose vehicle or lamotrigine(subtherapeutic dose,ie,5 mg/kg).Vehicle vs lamotrigine-kindled mice were compared in terms of(a)resistance/response toward nine antiseizure drugs applied as monotherapies and two drug combinations;(b)lamotrigine bioavailability in blood and brain;(c)blood-brain barrier integrity;and(d)amino acids and monoamines in the cerebral cortex and hippocampus.Results:Lamotrigine vs vehicle-kindled mice are similar(or not significantly different P>.05 from each other)in terms of(a)response toward drug combinations;(b)lamotrigine bioavailability;and(c)blood-brain barrier integrity except for,significantly(P<.05)reduced taurine and increased glutamate in the cerebral cortex and hippocampus.Aside from these,lamotrigine-kindled mice show significant(P<.05)resistant to lamotrigine(15 mg/kg),levetiracetam(40 mg/kg);carbamazepine(40 mg/kg),zonisamide(100 mg/kg),gabapentin(224 mg/kg),pregabalin(30 mg/kg),phenytoin(35 mg/kg),and topiramate(300 mg/kg).Conclusion:Lamotrigine-pentylenetetrazole kindling takes longer to develop(~5 weeks)in comparison to lamotrigine-amygdale(~4 weeks)and lamotriginecorneal(~2 weeks)kindling models.However,drug screening through this model may yield superior drugs with novel antiseizure mechanisms.
文摘BACKGROUND Pyogenic ventriculitis caused by extensively drug-resistant Acinetobacter baumannii(A.baumannii)is one of the most severe complications associated with craniotomy.However,limited therapeutic options exist for the treatment of A.baumannii ventriculitis due to the poor penetration rate of most antibiotics through the blood-brain barrier.CASE SUMMARY A 68-year-old male patient with severe traumatic brain injury developed pyogenic ventriculitis on postoperative day 24 caused by extensively drug-resistant A.baumannii susceptible to tigecycline only.Successful treatment was accomplished through multi-route administration of tigecycline,including intravenous combined with continuous ventricular irrigation plus intraventricular administration.The pus was cleared on the 3rd day post-irrigation,and cerebrospinal fluid cultures were negative after 12 d.CONCLUSION Our findings suggest that multi-route administration of tigecycline can be a therapeutic option against pyogenic ventriculitis caused by extensively drugresistant A.baumannii.
文摘Listeria monocytogenes is the pathogen of listeriosis and it causes severe infections like septicemia, encephalitis, and meningitis, especially in immunocompromised individuals, newborns, and pregnant women. Its wide distribution in the environment and ability to survive or even grow under adverse conditions has made L. monocytogenes an important public health concern and in food industry.
文摘Objective: Drug resistance is considered one of the main threats for tuberculosis control. Our aim was to identify risk factors for drug resistance in tuberculosis patients in the Northern Portugal. Study Design and Methods: Retrospective case-control study. The medical records and drug susceptibility test data from TB patients diagnosed between 31 March 2009 and 1 April 2010 were examined. We enrolled 119 patients with any drug resistance to first line anti-TB drugs and 238 with drug-susceptible TB, matched by age group. Variables analyzed included: gender, country of origin, employment situation, site of disease, previous treatment, presence of diabetes mellitus, HIV infection, alcohol abuse, intravenous drug use, abuse of other drugs and smoking habits. Multivariate conditional logistic regression was used to identify independent predictors for drug-resistant TB. Results: Diabetes mellitus [adjusted odds ratio (OR): 3.54;95% CI: 1.45 - 8.66], intravenous drug use (OR: 4.77;95% CI: 1.24 - 18.32) and previous TB treatment (OR: 2.48;95% CI: 1.12 - 5.49) were found to be risk factors for drug-resistant disease development. Conclusions: Diabetes mellitus, prior tuberculosis treatment, and intravenous drug use were risk factors for drug-resistant disease. The association between diabetes and drug-resistant TB should be further explored. Identifying clinical predictors of drug resistance can allow prompt identification of patients at risk for drug-resistant TB.
基金supported by International Joint Laboratory on Tropical Diseases Control in Greater Mekong Subregion(grant number 21410750200)from Shanghai Municipality Government.
文摘Background:Tuberculosis(TB),caused by Mycobacterium tuberculosis,remains the second leading cause of death from a single infectious disease globally and poses a significant economic and clinical burden in the world in 2022.Of particular concern is the emergence of drug-resistant TB,accounting for 15%-20%of TB deaths.It is imperative to delve into the global trends of incidence and death rate for multidrug-resistant tuberculosis(MDRTB)and extensively drug-resistant tuberculosis(XDR-TB),drawing upon the comprehensive Global Burden of Disease(GBD)2021 drug-resistant tuberculosis dataset.Methods:From the GBD 2021,data on incidence,prevalence,disability-adjusted life years(DALYs),and death of MDR-TB and XDR-TB from 1990 to 2021 were collected.We calculated the estimated annual percentage changes in age standardized incidence rate(ASIR)and age-standardized death rate(ASDR),segmented by age,sex,and socio-demographic index(SDI).The impacts of various risk factors on MDR-TB and XDR-TB were also analyzed.Results:In 2021,there were an estimated 443,680(95%uncertainty interval[UI]:259,196-766,545)incident cases of MDR-TB,and an estimated 106,818(95%UI:41,612-211,854)death cases of MDR-TB,while there were an estimated 24,036(95%UI:17,144-34,587)incident cases of XDR-TB and 7,946(95%UI:3,326-14,859)death cases of XDR-TB.The incidence and death cases of MDR-TB were lowest in high SDI regions,whereas the incidence rates of XDR-TB in high-middle SDI regions were higher than those in middle SDI and high SDI regions.Conclusion:This study reported the disease burden of drug-resistant TB from 1990 to 2021.Until 2021,drugresistant TB is still a serious problem in low SDI countries,especially for high-risk age populations with highrisk factors.Controlling drug-resistant TB requires effective control strategies and healthcare systems.
基金The Key Projects in the National Science & Technology Pillar Program during the Eleventh Five-Year Plan Period of China (2008ZX10001-002)the Major Science and Technology Innovation Cross Project of the Chinese Academy of Sciences (KSCX1-YW-10)
文摘This study aimed to evaluate emerging trends of drug resistance to nucleoside reverse transcriptase inhibitors (NRTIs) and nonnucleoside reverse transcriptase inhibitors (NNRTIs) among 290 former blood donor HIV-1 infected patients in Hubei, China, from 2004 to 2006, all of whom had received anti-HIV-1 therapy. The presence of NRTI- and NNRTI-associated mutations were established by sequencing; genotypic and predicted phenotypic drug resistance were evaluated using HIVdb Program version 5.0.1 (http://hivdb.stanford.edu/ pages/algs/HIVdb.html). Genotypic drug resistance analysis showed significant increases in percentages of patients carrying HIV-1 strains with M41L, T215Y/F, D67N, K103N, G190A/S, Y181C/F or L210W mutations. Of the variants' predicted phenotypic drug resistance, highly significant increases were detected in percentages of patients carrying HIV-1 with high resistance to zidovudine (AZT) or stavudine (D4T) in NRTIs, and to delavirdine (DLV), efavirenz (EFV) or nevirapine (NVP) in NNRTIs; intermediate resistance to abacavir (ABC), AZT, D4T, didanosine (DDI) or tenofovir disoproxil fumarate (TDF) in NRTIs, and to etravirine (ETR) in NNRTIs; and low and potential low resistance to lamivudine (3TC), ABC, emtricitabine (FTC) or TDF in NRTIs, and to ETR in NNRTIs.
文摘Introduction: The emergency of Mycobacterium tuberculosis resistant to the first line drug reduced access possibility to second line drugs for appropriate treatment and required for urgent action especially in le Democratic Republic of Congo (DRC), which counts among the highest tuberculosis (TB) burden countries in Africa. Objective: To present prevalence and describe multidrug-resistant tuberculosis cases in North-Kivu Province identified by using Genexpert technology. Methods: We conducted an observational prospective study on multidrug-resistant tuberculosis (MDR-TB) cases in North-Kivu Province, DRC from 2017 to 2018. All cases of MDR-TB identified by Genexpert MTB/ RIB were included in this series. Result: Of 15,544 tuberculosis cases registered during the study period, 19 cases of MDR-TB were identified. 57.9% was male, 89.5% was retreatment cases and 5.3% was coinfection HIV/TB cases. Conclusion: This new molecular technology diagnostic facilitates multidrug-resistance tuberculosis detection and improves the reporting of data lack.
文摘There are various bacteria living in this world. The most common one is Staphylococcus aureus. Almost everyone has heard of it. It is easy to find their habitats, such as hospitals, homes, parks, schools etc. Some of them are difficult to be eliminated because of drug-resistant mutations. Hence, lots of researchers devoted their efforts to eliminate them. This review illustrates the characteristics of the Staphylococcus aureus and the main threat of their drug-resistant strains, especially methicillin-resistant S. aureus. What’s more, the article also highlights the plight in the drug development.
文摘BACKGROUND Perampanel(PER),a third-generation antiepileptic drug,is a selective and noncompetitiveα-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor antagonist,and has been approved for the treatment of adults and adolescents with focal epilepsy.However,there are only a few studies about the efficacy and tolerability of PER in young children with multidrug-resistant epilepsy.In this case,we aimed to share our clinical experience in this group.CASE SUMMARY A 4-year-old boy without perinatal asphyxia and familial history of epilepsy began to have ictal seizures from age 14 mo,with jerky movement of four limbs and head nodding.Abnormal multifocal discharge and background activity were recorded through electroencephalography,and no pathogenic mutation was found in the whole exome sequencing for the patient and his parents.He had received valproate,levetiracetam,topiramate,oxcarbazepine,clonazepam and lacosamide sequentially at different times,but he still had frequent seizures even after vagus nerve stimulation(VNS)implantation.He was diagnosed with idiopathic multidrug-resistant epilepsy.However,his seizure frequency was significantly reduced after PER administration in a dose-dependent manner,and better cognitive behavior was observed.In addition,the adverse reactions of anger and aggression also appeared.CONCLUSION PER is effective as add-on therapy for young children with multidrug-resistant epilepsy who have previously undergone VNS implantation.
文摘Objectives: Bedaquiline (BDQ) is the first new anti-tuberculosis (TB) drug introduced to the market after 45 years. Recent studies have shown the potential benefits of adding bedaquiline to regimens for drug-resistant TB (DR-TB). In search of more effective regimens for DR-TB, bedaquiline was introduced in the TB program in the Philippines under operational research to assess its effectiveness, safety, and tolerability when given with background regimens among patients with multi-or extensively DR-TB (MDR/XDR-TB). Design: A prospective cohort study of patients with MDR/XDR-TB was given with a bedaquiline-containing regimen from June 2016 to May 2017. Demographic data, presence of comorbidities, and microbiologic profile on entry were recorded. Bedaquiline was administered at the recommended dose of 400 mg once daily for 14 days, then 200 mg three times a week for 22 weeks together with World Health Organization (WHO)-compliant background regimen. The time to culture conversion, interim outcomes at the 6th month of treatment, end-of-treatment outcomes, and post-treatment follow-up outcomes after one year was determined. The frequency and severity of adverse events (SAE) were recorded as part of pharmacovigilance. Results: Seventy-five patients were given with bedaquiline-containing regimen during the study period. Forty-two (56.0%) had second-line injectable resistance, 23 (30.7%) had fluoroquinolone-resistance, 6 (8.0%) had MDR-TB, and 4 (5.3%) had XDR-TB. In the 6th month of post-enrolment, 79% were culture-negative. The treatment success rate was 65.3% (37 were cured and 12 completed treatment), 7 (9.3%) died, 17 (22.7%) lost to follow-up, and 2 (2.7%) were withdrawn from treatment. Adverse events included vomiting (80%), dizziness (69%), nausea (52%), cough (44%), and headache (36%). The post-treatment follow-up of 49 patients in the 12th month showed 92% were culture-negative while 8% of TBC were not done. Conclusion: Bedaquiline-containing regimens for patients with MDR/XDR-TB were highly effective with an acceptable safety profile and favorable treatment outcomes, but the proportion of patients who lost to follow-up remains substantial.
基金Science and Technology Projects in Key Fields of Traditional Chinese Medicine in Tianjin(No.2021010)Discipline Development Fund of First Teaching Hospital of Tianjin University of Traditional Chinese Medicine(No.XKJJ201734)。
文摘Objective:To establish extensively drug-resistant Pseudomonas aeruginosa(XDR-PA)infection-induced pneumonia model in rats.Methods:Twenty-four male SD rats were randomly divided into blank group,low bacterial group,medium bacterial group,and high bacterial group.The low,medium and high bacterial groups were given intratracheal instillation of 0.1 mL of bacterial suspension(bacterial concentration in turn is 7.5×10^(9),3×10^(10),6×10^(10)CFU/mL),while the blank group were given the same volume of sterile normal saline.After modeling,the general conditions of rats in each group were observed,including mental state,hair,respiration,activity,eating,weight,and the survival curve was drawn.The pathological characteristics of lung tissue and the infiltration of inflammatory cells were observed.Pathogenic identification of each group was carried out by bacterial culture of lung tissue homogenate.Results:The general state of the blank group was normal,and the rats in other groups showed signs of mental depression,bristling,shortness of breath,even oral and nasal bleeding,decreased food intake and activity,and significant weight loss,and different degrees of death within 48 hours,the difference was statistically significant(P<0.05).Pathological results showed that the alveolar structure of rats in the blank group was complete,and the alveolar space was clear without exudation.The lung tissue of the low and medium bacterial groups showed obvious inflammatory cell infiltration,alveolar structure destruction,alveolar septum thickening,interstitial edema,but the pathological damage of the medium group was more severe,with a mortality rate of up to 50%,and the mortality rate of the low bacterial group was 17%.In the high bacterial group,red blood cells,inflammatory cells and a large amount of fibrin-like exudation can be seen in the alveolar space,which has the pathological characteristics of acute respiratory failure,and the mortality rate is as high as 67%.The results of bacterial culture of lung tissue homogenate showed that the blank group had no bacterial colonies,while PA colony growth can be seen in low,medium and high bacterial groups.Conclusion:9 Intratracheal instillation of low bacterial count(0.1 mL of 7.5×10^(9) CFU/mL)XDR-PA bacterial suspension can successfully construct a rat pneumonia model of XDR-PA infection.
