In compartment fires (houses, buildings, underground, warehouse, etc.), smokes are a major dan- ger during firemen intervention. Most of the time, they are at high temperature (>800?C) and they flow everywhere thro...In compartment fires (houses, buildings, underground, warehouse, etc.), smokes are a major dan- ger during firemen intervention. Most of the time, they are at high temperature (>800?C) and they flow everywhere through many kinds of ducts, which leads to the propagation of the combustion by the creation other fires in places which may be far away from the initial fire. In this paper, we present a new approach of the problem, which allows to better follow the fire behavior and especially to detect the dangers that may appear and endanger firefighters. This approach consists in a mathematical analysis based on the comparison of moving averages centered in the past, calculated on the temperature recordings of the smokes. As a consequence, this method may allow to improve decision support in real time and therefore to improve the security and the efficiency of firefighters in their operations against that kind of fires.展开更多
The muzzle blast overpressure induces disturbances in the flow field inside the crew compartment(FFICC)of a truck-mounted howitzer during the artillery firing.This overpressure is the primary factor preventing personn...The muzzle blast overpressure induces disturbances in the flow field inside the crew compartment(FFICC)of a truck-mounted howitzer during the artillery firing.This overpressure is the primary factor preventing personnel from firing artillery within the cab.To investigate the overpressure characteristics of the FFICC,a foreign trade equipment model was used as the research object,and a numerical model was established to analyze the propagation of muzzle blast from the muzzle to the interior of the crew compartment under extreme firing condition.For comparative verification,the muzzle blast experiment included overpressure data from both the flow field outside the crew compartment(FFOCC)and the FFICC,as well as the acceleration data of the crew compartment structure(Str-CC).The research findings demonstrate that the overpressure-time curves of the FFICC exhibit multi-peak characteristics,while the pressure wave shows no significant discontinuity.The enclosed nature of the cab hinders the dissipation of pressure wave energy within the FFICC,leading to sustained high-amplitude overpressure.The frameskin structure helps attenuate the impact of muzzle blast on the FFICC.Conversely,local high overpressure caused by the convex or concave features of the cab's exterior significantly amplifies the overpressure amplitude within the FFICC.展开更多
Acute compartment syndrome(ACoS)involves a complex pathological process in which rising pressures within an enclosed muscle space ultimately result in anoxia and cell death.The most common etiologies include long bone...Acute compartment syndrome(ACoS)involves a complex pathological process in which rising pressures within an enclosed muscle space ultimately result in anoxia and cell death.The most common etiologies include long bone fractures,crush injuries,and burns.[1,2]While rare,ACoS can also occur in atraumatic settings following periods of prolonged limb compression,such as intoxication.[3]Atraumatic ACoS is easily overlooked,resulting in diagnostic delay and poor patient outcomes.Prompt recognition and surgical management is essential to prevent critical sequelae.展开更多
BACKGROUND Hypoganglionosis is a rare gastrointestinal acquired motility disorder that res-embles Hirschsprung’s disease and can manifest in the adult life.Abdominal compartment syndrome,a condition characterized by ...BACKGROUND Hypoganglionosis is a rare gastrointestinal acquired motility disorder that res-embles Hirschsprung’s disease and can manifest in the adult life.Abdominal compartment syndrome,a condition characterized by an increase in intra-abdo-minal pressure with physiological disturbance can be caused by severe massive fecal impaction.CASE SUMMARY A 33-year-old female presented to the emergency room with massive abdominal distension that rapidly progressed to abdominal compartment syndrome.The pa-tient was diagnosed with hypoganglionosis.Life-saving emergent proctoco-lectomy was performed to save the patient.CONCLUSION Abdominal compartment syndrome can develop secondary to excessive colonic distension.This extreme but rare situation must be addressed immediately.Hypo-ganglionosis is a potential cause of severe constipation that may present in adu-lthood.展开更多
The gene encoded for tryptophan decarboxylase (TDC), which is the key enzyme in terpenoil indole alkaloids pathway, was targeted to different subcellular compartments and stably expressed in transgenic tobacco (Nicoti...The gene encoded for tryptophan decarboxylase (TDC), which is the key enzyme in terpenoil indole alkaloids pathway, was targeted to different subcellular compartments and stably expressed in transgenic tobacco (Nicotiana tabacum L.) plants at the levels detected by Western blot and tryptamine accumulation analysis. It was shown that the TDC was located in subcellular compartments, the chloroplasts and cytosol. The recombinant TDC targeted to chloroplasts and cytosol in tobacco plants was effectively expressed as soluble protein by Western blot analysis and enzymatic assay. The level of tryptamine accumulation in chloroplast was higher than that in cytosol and very low in vacuole and endoplasmic reticulum (ER) to be hardly detected by Western blot analysis. It was indicated that the highest amount of tryptamine was in chloroplasts, lower in endoplasmic reticula and the lowest in vacuoles as compared to those in wild type plants. The TDC targeted to different subcellular compartments of tobacco plants and its expression level were studied by different nucleotide sequences coding signal peptides at 5'-end of tdc gene in order to know the effects of the TDC in compartmentation on its functionality.展开更多
In this paper,we propose a probabilistic method for analysing the collapse time of steel frame structures in a fire.The method considers the uncertainty of influencing factors.Tornado diagrams are used for sensitivity...In this paper,we propose a probabilistic method for analysing the collapse time of steel frame structures in a fire.The method considers the uncertainty of influencing factors.Tornado diagrams are used for sensitivity analysis of random variables.Structural analysis samples are selected by Monte Carlo method,and the collapse times of different structural samples are calculated by fire time history analysis.A collapse time fragility curve is fitted according to the calculated collapse times of the samples.A reliability index of the collapse time is used as a quantitative standard to evaluate the collapse performance of a steel frame in a fire.Finally,this method is applied to analyse the collapse time fragility of an eight-storey 3 D steel frame structure under different compartment fire scenarios and fire protection levels.According to the collapse time fragility curve,the effects of the different fire scenarios and protection levels on the collapse resistance of the structure under fire are evaluated.展开更多
The two compartment model with variable extracellular volume is presented and solved by using both perturbation and analytical method. The computation for both creatinine and urea show that the perturbation solution ...The two compartment model with variable extracellular volume is presented and solved by using both perturbation and analytical method. The computation for both creatinine and urea show that the perturbation solution is not only simple but also accurate enough and is a good substitute for the more exact analytical solution.展开更多
Strictosidine synthase (STR) is a key enzyme involved in the biosynthesis of terpenoid indole alkaloids (TIA) by condensing tryptamine and secologanin into strictosidine. The transgenic tobacco plants targeting STR to...Strictosidine synthase (STR) is a key enzyme involved in the biosynthesis of terpenoid indole alkaloids (TIA) by condensing tryptamine and secologanin into strictosidine. The transgenic tobacco plants targeting STR to subcellular compartments were established to express STR in chloroplast, vacuole and endoplasmic reticulum (ER) by the tobacco stable transformation. It was shown that STR was effectively expressed in the above subcellular compartments by Western blot analysis and STR enzymatic assay. In vitro , STR enzymatic assay was measured indirectly by fluorimetrically detecting depletion of tryptamine feeding on secologanin in the reaction mixture. The tryptamine were completely depleted by STR in the crude extract of leaves of transgenic tobacco plants targeting and expressing STR in the chloroplast, vacuole and ER, which ascertained the STR functionally targeted to the three subcellular compartments. To confirm STR correct targeting and expressing in chloroplast, the chloroplasts were isolated and the fractions of purified chloroplasts were analyzed by Western blot. The hypothesis of STR correct targeting to the chloroplast was tested. The results have implications on our understanding of the complex intracellular trafficking in metabolic intermediates of TIA biosynthesis.展开更多
Dendritic spines are small protrusions along dendrites that contain most of the excitatory synapses in principal neurons,playing a crucial role in neuronal function by creating a compartmentalized environment for sign...Dendritic spines are small protrusions along dendrites that contain most of the excitatory synapses in principal neurons,playing a crucial role in neuronal function by creating a compartmentalized environment for signal transduction.The plasticity of spine morphologies provides a tunable handle to regulate calcium signal dynamics,allowing rapid regulation of protein expression necessary to establish and maintain synapses(Cornejo et al.,2022).If excitatory inputs were to be located primarily on dendritic shafts,dendrites would frequently short-circuit,preventing voltage signals from propagating(Cornejo et al.,2022).It is thus not surprising that the structural plasticity of dendritic spines is closely linked to synaptic plasticity and memory formation(Berry and Nedivi,2017).While comprehensive in vitro studies have been conducted,in vivo studies that directly tackle the mechanism of dendritic transport and translation in regulating spine plasticity spatiotemporally are limited.展开更多
AIM: To study retrospectively the influence of intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS) in patients with early acute pancreatitis (AP) (during the first week after admission) on phys...AIM: To study retrospectively the influence of intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS) in patients with early acute pancreatitis (AP) (during the first week after admission) on physiological functions, and the association of the presence of IAH/ACS and outcome. METHODS: Patients (n = 74) with AP recruited in this study were divided into two groups according to intra-abdominal pressure (IAP) determined by indirect measurement using the transvesical route via Foley bladder catheter during the first week after admission. Patients (n = 44) with IAP ≥ 12 mmHg were assigned in IAH group, and the remaining patients (n = 30) with IAP < 12 mmHg in normal IAP group. For analysis of the influence of IAH/ACS on organ function and outcome, the physiological parameters and the occurrence of organ dysfunction during intensive care unit (ICU) stay were recorded, as were the incidences of pancreatic infection and in-hospital mortality. RESULTS: IAH within the first week after admission was found in 44 patients (59.46%). Although the APACHE Ⅱ scores on admission and the Ranson scores within 48 h after hospitalization were elevated in IAH patients in early stage, they did not show the statistically significant differences from patients with normal IAP within a week after admission (16.18 ± 3.90 vs 15.70 ± 4.25, P = 0.616; 3.70 ± 0.93 vs 3.47 ± 0.94, P = 0.285, respectively). ACS in early AP was recorded in 20 patients (27.03%). During any 24-h period ofthe first week after admission, the recorded mean IAP correlated significantly with the Marshall score calculated at the same time interval in IAH group (r = 0.635, P < 0.001). Although ACS patients had obvious amelioration in physiological variables within 24 h after decompression, the incidences of pancreatitic infection, septic shock, multiple organ dysfunction syndrome (MODS) and death in the patients with ACS were significantly higher than that in other patients without ACS (pancreatitic infection: 60.0% vs 7.4%, P < 0.001; septic shock: 70.0% vs 11.1%, P < 0.001; MODS: 90.0% vs 31.5%, P < 0.001; mortality: 75.0% vs 3.7%, P < 0.001). CONCLUSION: IAH/ACS is a frequent finding in patients admitted to the ICU because of AP. Patients with IAP at approximately 10-12 mmHg and early signs of changes in physiologic variables should be seriously considered for urgent decompression to improve survival.展开更多
AIM： To assess the value of widely used clinical scores in the early identification of acute pancreatitis （AP） patients who are likely to suffer from intra-abdominal hypertension （IAH） and abdominal compartment s...AIM： To assess the value of widely used clinical scores in the early identification of acute pancreatitis （AP） patients who are likely to suffer from intra-abdominal hypertension （IAH） and abdominal compartment syndrome （ACS）.METHODS： Patients （η = 44） with AP recruited in this study were divided into two groups （ACS and non-ACS） according to intra-abdominal pressure （IAP） determined by indirect measurement using the transvesical route via Foley bladder catheter. On admission and at regular intervals, the severity of the AP and presence of organ dysfunction were assessed utilizing different multifactorial prognostic systems： Glasgow-Imrie score, Acute Physiology and Chronic Health Evaluation Ⅱ （APACHE-Ⅱ） score, and Multiorgan Dysfunction Score （MODS）. The diagnostic performance of scores predicting ACS development, cut-off values and specificity and sensitivity were established using receiver operating characteristic （ROC） curve analysis.RESULTS： The incidence of ACS in our study population was 19.35%. IAP at admission in the ACS group was 22.0 （18.5-25.0） mmHg and 9.25 （3.0-12.4） mmHg in the non-ACS group （P 〈 0.01）. Univariate statistical analysis revealed that patients in the ACS group had significantly higher multifactorial clinical scores （APACHE Ⅱ, Glasgow-Imrie and MODS） on admission and higher maximal scores during hospitalization （P 〈 0.01）. ROC curve analysis revealed that APACHE Ⅱ, Glasgow-Imrie, and MODS are valuable tools for early prediction of ACS with high sensitivity and specificity, and that cut-off values are similar to those used for stratification of patients with severe acute pancreatitis （SAP）.CONCLUSION： IAH and ACS are rare findings in patients with mild AR Based on the results of our study we recommend measuring the IAP in cases when patients present with SAP （APACHE Ⅱ 〉 7; MODS 〉 2 or Glasgow-Imrie score 〉 3）.展开更多
AIM: To investigate the therapeutic effect of traditional Chinese traditional medicines Da Cheng Qi Decoction (Timely-Purging and Yin-Preserving Decoction) and Glauber's salt combined with conservative measures on...AIM: To investigate the therapeutic effect of traditional Chinese traditional medicines Da Cheng Qi Decoction (Timely-Purging and Yin-Preserving Decoction) and Glauber's salt combined with conservative measures on abdominal compartment syndrome (ACS) in severe acute pancreatitis (SAP) patients. METHODS: Eighty consecutive SAP patients, admitted for routine non-operative conservative treatment, were randomly divided into study group and control group (40 patients in each group). Patients in the study group received Da Cheng Qi Decoction enema for 2 h and external use of Glauber's salt, once a day for 7 d. Patients in the control group received normal saline (NS) enema. Routine non-operative conservative treatments included non-per os nutrition (NPON), gastrointestinal decompression, life support, total parenteral nutrition (TPN), continuous peripancreatic vascular pharmaceutical infusion and drug therapy. Intra-cystic pressure (ICP) of the two groups was measured during treatment. The effectiveness and outcomes of treatment were observed and APACHE Ⅱ scores were applied in analysis. RESULTS: On days 4 and 5 of treatment, the ICP was lower in the study group than in the control group(P < 0.05). On days 3-5 of treatment, acute physiology and chronic health evaluation Ⅱ (APACHE Ⅱ) scores for the study and control groups were significantly different (P < 0.05). Both the effectiveness and outcome of the treatment with Da Cheng Qi Decoction on abdominalgia, burbulence relief time, ascites quantity, cyst formation rate and hospitalization time were quite different between the two groups (P < 0.05). The mortality rate for the two groups had no significant difference. CONCLUSION: Da Cheng Qi Decoction enema and external use of Glauber's salt combined with routine non-operative conservative treatment can decrease the intra-abdominal pressure (IAP) of SAP patients and have preventive and therapeutic effects on abdominal compartment syndrome of SAP.展开更多
This survey was designed to clarify the current understanding and clinical management of intra-abdominal hypertension （IAH）/abdominal compartment syndrome （ACS） among intensive care physicians in tertiary Chinese ...This survey was designed to clarify the current understanding and clinical management of intra-abdominal hypertension （IAH）/abdominal compartment syndrome （ACS） among intensive care physicians in tertiary Chinese hospitals. A postal twenty-question questionnaire was sent to 141 physicians in different intensive care units （ICUs）. A total of 108 （76.6%） questionnaires were returned. Among these, three quarters worked in combined medical-surgical ICUs and nearly 80% had primary training in internal or emergency medicine. Average ICU beds, annual admission, ICU length of stay, acute physiology and chronic health evaluation （APACHE）II score, and mortality were 18.2 beds, 764.5 cases, 8.3 d, 19.4, and 21.1%, respectively. Of the respondents, 30.6% never measured intra-abdominal pressure （IAP）. Although the vast majority of the ICUs adopted the exclusively transvesicular method, the over- whelming majority （88.0%） only measured lAP when there was a clinical suspicion of IAH/ACS and only 29.3% measured either often or routinely. Moreover, 84.0% used the wrong priming saline volume while 88.0% zeroed at reference points which were not in consistence with the standard method for lAP monitoring recommended by the World Society of Abdominal Compartment Syndrome. ACS was suspected mainly when there was a distended ab- domen （92%）, worsening oliguria （80%）, and increased ventilatory support requirement （68%）. Common causes for IAH/ACS were ＂third-spacing from massive volume resuscitation in different settings＂ （88%）, ＂intra-abdominal bleeding＂, and ＂liver failure with ascites＂ （52% for both）. Though 60% respondents would recommend surgical decompression when the lAP exceeded 25 mmHg, accompanied by signs of organ dysfunction, nearly three quarters of re- spondents preferred diuresis and dialysis. A total of 68% of respondents would recommend paracentesis in the treatment for ACS. In conclusion, urgent systematic education is absolutely necessary for most intensive care physicians in China to help to establish clear diagnostic criteria and appropriate management for these common, but life-threatening, diseases.展开更多
Intra-abdominal hypertension(IAH)and abdominal compartment syndrome are well recognized entities among surgical patients.Nevertheless,a number of prospective and retrospective observational studies have shown that IAH...Intra-abdominal hypertension(IAH)and abdominal compartment syndrome are well recognized entities among surgical patients.Nevertheless,a number of prospective and retrospective observational studies have shown that IAH is prevalent in about half of the critically ill patients in the medical intensive care units(ICU)and has been widely recognized as an independent risk factor for mortality.It is alarming to note that many members of the critical care team in medical ICU are not aware of the consequences of untreated IAH and the delay in making the diagnosis leads to increased morbidity and mortality.Frequently it is underdiagnosed and undertreated in this patient population.Elevated intraabdominal pressure decreases the blood flow to the kidneys and other abdominal viscera and also results in reduced cardiac output and difficulties in ventilating the patient because of increased intrathoracic pressure.When intraabdominal hypertension is not promptly recognized and treated,it leads to abdominal compartment syndrome,multiorgan dysfunction syndrome and death.Large volume fluid resuscitation is very common in medical ICU patients presenting with sepsis,shock and other inflammatory conditions like pancreatitis and it is one of the major risk factors for the development of intra-abdominal hypertension.This article presents an overview of the epidemiology,definitions,risk factors,pathophysiology and management of IAH and abdominal compartment syndrome in critically ill medical ICU patients.展开更多
AIM： To study the effect of combined indwelling catheter, hemofiltration, respiration support and traditional Chinese medicine （e.g. Dahuang） in treating abdominal compartment syndrome of fulminant acute pancreatit...AIM： To study the effect of combined indwelling catheter, hemofiltration, respiration support and traditional Chinese medicine （e.g. Dahuang） in treating abdominal compartment syndrome of fulminant acute pancreatitis. METHODS： Patients with fulminant acute pancreatitis were divided randomly into 2 groups of combined indwelling catheter celiac drainage and intra-abdominal pressure monitoring and routine conservative measures group （group 1） and control group （group 2）. Routine non-operative conservative treatments including hemofiltration, respiration support, gastrointestinal TCM ablution were also applied in control group patients. Effectiveness of the two groups was observed, and APACHE Ⅱ scores were applied for analysis. RESULTS： On the second and fifth days after treatment, APACHE Ⅱ scores of group 1 and 2 patients were significantly different. Comparison of effectiveness （abdominalgia and burbulence relief time, hospitalization time） between groups 1 and 2 showed significant difference, as well as incidence rates of cysts formation. Mortality rates of groups 1 and 2 were 10.0% and 20.7%, respectively. For patients in group 1, celiac drainage quantity and intra-abdominal pressure, and hospitalization time were positively correlated （r = 0.552, 0.748, 0.923, P 〈 0.01） with APACHE Ⅱ scores. CONCLUSION： Combined indwelling catheter celiac drainage and intra-abdominal pressure monitoring, short veno-venous hemofiltration （SVVH）, gastrointestinal TCM ablution, respiration support have preventive and treatment effects on abdominal compartment syndrome of fulminant acute pancreatitis.展开更多
The SEIR epidemic model studied here includes constant inflows of new susceptibles, exposeds, infectives, and recovereds. This model also incorporates a population size dependent contact rate and a disease-related dea...The SEIR epidemic model studied here includes constant inflows of new susceptibles, exposeds, infectives, and recovereds. This model also incorporates a population size dependent contact rate and a disease-related death. As the infected fraction cannot be eliminated from the population, this kind of model has only the unique endemic equilibrium that is globally asymptotically stable. Under the special case where the new members of immigration are all susceptible, the model considered here shows a threshold phenomenon and a sharp threshold has been obtained. In order to prove the global asymptotical stability of the endemic equilibrium, the authors introduce the change of variable, which can reduce our four-dimensional system to a three-dimensional asymptotical autonomous system with limit equation.展开更多
Osteocytes, the most abundant bone cells, form an interconnected network in the lacunar-canalicular pore system （LCS） buried within the mineralized matrix, which allows osteocytes to obtain nutrients from the blood ...Osteocytes, the most abundant bone cells, form an interconnected network in the lacunar-canalicular pore system （LCS） buried within the mineralized matrix, which allows osteocytes to obtain nutrients from the blood supply, sense external mechanical signals, and communicate among themselves and with other cells on bone surfaces. In this study, we examined key features of the LCS network including the topological parameter and the detailed structure of individual connections and their variations in cortical and cancellous compa~ tments, at different ages, and in two disease conditions with altered mechanosensing （perlecan deficiency and diabetes）. LCS network showed both topological stability, in terms of conservation of connectivity among osteocyte lacunae （similar to the ＂nodes＂ in a computer network）, and considerable variability the pericellular annular fluid gap surrounding lacunae and canaliculi （similar to the ＂bandwidth＂ of individual links in a computer network）. Age, in the range of our study （15-32 weeks）, affected only the pericellular fluid annulus in cortical bone but not in cancellous bone. Diabetes impacted the spacing of the lacunae, while the perlecan deficiency had a profound influence on the pericellular fluid annulus. The LCS network features play important roles in osteocyte signaling and regulation of bone growth and adaptation.展开更多
Acute compartment syndrome(ACS) of the thigh following primary total hip arthroplasty(THA) is a highly uncommon complication and has not yet been reported before with regards to the anterior approach through the anter...Acute compartment syndrome(ACS) of the thigh following primary total hip arthroplasty(THA) is a highly uncommon complication and has not yet been reported before with regards to the anterior approach through the anterior supine interval. We present a case of a 69-year-old male patient with a history of stroke, who developed ACS of the thigh after elective THA while using therapeutic low molecular weight heparin as bridging for regular oral anticoagulation. ACS pathogenesis, diagnostic tools, treatment and relevant literature are discussed. The patient's ACS was recognized in time and treated by operative decompression with fasciotomy of the anterior compartment. Follow-up did not show any neurological deficit or soft-tissue damage.展开更多
Abdominal compartment syndrome(ACS)develops when organ failure arises secondary to an increase in intraabdominal pressure.The abdominal pressure is determined by multiple factors such as blood pressure,abdominal compl...Abdominal compartment syndrome(ACS)develops when organ failure arises secondary to an increase in intraabdominal pressure.The abdominal pressure is determined by multiple factors such as blood pressure,abdominal compliance,and other factors that exert a constant pressure within the abdominal cavity.Several conditions in the critically ill may increase abdominal pressure compromising organ perfusion that may lead to renal and respiratory dysfunction.Among surgical and trauma patients,aggressive fluid resuscitation is the most commonly reported risk factor to develop ACS.Other conditions that have also been identified as risk factors are ascites,hemoperitoneum,bowel distention,and large tumors.All patients with abdominal trauma possess a higher risk of developing intra-abdominal hypertension(IAH).Certain surgical interventions are reported to have a higher risk to develop IAH such as damage control surgery,abdominal aortic aneurysm repair,and liver transplantation among others.Close monitoring of organ function and intra-abdominal pressure(IAP)allows clinicians to diagnose ACS rapidly and intervene with target-specific management to reduce IAP.Surgical decompression followed by temporary abdominal closure should be considered in all patients with signs of organ dysfunction.There is still a great need for more studies to determine the adequate timing for interventions to improve patient outcomes.展开更多
Intra-abdominal hypertension(IAH)and abdominal compartment syndrome(ACS)play a pivotal role in the pathophysiology of severe acute pancreatitis(SAP)and contribute to new-onset and persistent organ failure.The optimal ...Intra-abdominal hypertension(IAH)and abdominal compartment syndrome(ACS)play a pivotal role in the pathophysiology of severe acute pancreatitis(SAP)and contribute to new-onset and persistent organ failure.The optimal management of ACS involves a multi-disciplinary approach,from its early recognition to measures aiming at an urgent reduction of intra-abdominal pressure(IAP).A targeted literature search from January 1,2000,to November 30,2022,revealed 20 studies and data was analyzed on the type and country of the study,patient demographics,IAP,type and timing of surgical procedure performed,post-operative wound management,and outcomes of patients with ACS.There was no randomized controlled trial published on the topic.Decom-pressive laparotomy is effective in rapidly reducing IAP(standardized mean difference=2.68,95%confidence interval:1.19-1.47,P<0.001;4 studies).The morbidity and complications of an open abdomen after decompressive laparotomy should be weighed against the inadequately treated but,potentially lethal ACS.Disease-specific patient selection and the role of less-invasive decompressive measures,like subcutaneous linea alba fasciotomy or component separation techniques,is lacking in the 2013 consensus management guidelines by the Abdominal Compartment Society on IAH and ACS.This narrative review focuses on the current evidence regarding surgical decompression techniques for managing ACS in patients with SAP.However,there is a lack of high-quality evidence on patient selection,timing,and modality of surgical decompression.Large prospective trials are needed to identify triggers and effective and safe surgical decompression methods in SAP patients with ACS.展开更多
文摘In compartment fires (houses, buildings, underground, warehouse, etc.), smokes are a major dan- ger during firemen intervention. Most of the time, they are at high temperature (>800?C) and they flow everywhere through many kinds of ducts, which leads to the propagation of the combustion by the creation other fires in places which may be far away from the initial fire. In this paper, we present a new approach of the problem, which allows to better follow the fire behavior and especially to detect the dangers that may appear and endanger firefighters. This approach consists in a mathematical analysis based on the comparison of moving averages centered in the past, calculated on the temperature recordings of the smokes. As a consequence, this method may allow to improve decision support in real time and therefore to improve the security and the efficiency of firefighters in their operations against that kind of fires.
基金supported by the National Natural Science Foundation of China(Grant No.U2341269)。
文摘The muzzle blast overpressure induces disturbances in the flow field inside the crew compartment(FFICC)of a truck-mounted howitzer during the artillery firing.This overpressure is the primary factor preventing personnel from firing artillery within the cab.To investigate the overpressure characteristics of the FFICC,a foreign trade equipment model was used as the research object,and a numerical model was established to analyze the propagation of muzzle blast from the muzzle to the interior of the crew compartment under extreme firing condition.For comparative verification,the muzzle blast experiment included overpressure data from both the flow field outside the crew compartment(FFOCC)and the FFICC,as well as the acceleration data of the crew compartment structure(Str-CC).The research findings demonstrate that the overpressure-time curves of the FFICC exhibit multi-peak characteristics,while the pressure wave shows no significant discontinuity.The enclosed nature of the cab hinders the dissipation of pressure wave energy within the FFICC,leading to sustained high-amplitude overpressure.The frameskin structure helps attenuate the impact of muzzle blast on the FFICC.Conversely,local high overpressure caused by the convex or concave features of the cab's exterior significantly amplifies the overpressure amplitude within the FFICC.
文摘Acute compartment syndrome(ACoS)involves a complex pathological process in which rising pressures within an enclosed muscle space ultimately result in anoxia and cell death.The most common etiologies include long bone fractures,crush injuries,and burns.[1,2]While rare,ACoS can also occur in atraumatic settings following periods of prolonged limb compression,such as intoxication.[3]Atraumatic ACoS is easily overlooked,resulting in diagnostic delay and poor patient outcomes.Prompt recognition and surgical management is essential to prevent critical sequelae.
文摘BACKGROUND Hypoganglionosis is a rare gastrointestinal acquired motility disorder that res-embles Hirschsprung’s disease and can manifest in the adult life.Abdominal compartment syndrome,a condition characterized by an increase in intra-abdo-minal pressure with physiological disturbance can be caused by severe massive fecal impaction.CASE SUMMARY A 33-year-old female presented to the emergency room with massive abdominal distension that rapidly progressed to abdominal compartment syndrome.The pa-tient was diagnosed with hypoganglionosis.Life-saving emergent proctoco-lectomy was performed to save the patient.CONCLUSION Abdominal compartment syndrome can develop secondary to excessive colonic distension.This extreme but rare situation must be addressed immediately.Hypo-ganglionosis is a potential cause of severe constipation that may present in adu-lthood.
文摘The gene encoded for tryptophan decarboxylase (TDC), which is the key enzyme in terpenoil indole alkaloids pathway, was targeted to different subcellular compartments and stably expressed in transgenic tobacco (Nicotiana tabacum L.) plants at the levels detected by Western blot and tryptamine accumulation analysis. It was shown that the TDC was located in subcellular compartments, the chloroplasts and cytosol. The recombinant TDC targeted to chloroplasts and cytosol in tobacco plants was effectively expressed as soluble protein by Western blot analysis and enzymatic assay. The level of tryptamine accumulation in chloroplast was higher than that in cytosol and very low in vacuole and endoplasmic reticulum (ER) to be hardly detected by Western blot analysis. It was indicated that the highest amount of tryptamine was in chloroplasts, lower in endoplasmic reticula and the lowest in vacuoles as compared to those in wild type plants. The TDC targeted to different subcellular compartments of tobacco plants and its expression level were studied by different nucleotide sequences coding signal peptides at 5'-end of tdc gene in order to know the effects of the TDC in compartmentation on its functionality.
基金Project supported by the National Natural Science Foundation of China (No. 51678358)。
文摘In this paper,we propose a probabilistic method for analysing the collapse time of steel frame structures in a fire.The method considers the uncertainty of influencing factors.Tornado diagrams are used for sensitivity analysis of random variables.Structural analysis samples are selected by Monte Carlo method,and the collapse times of different structural samples are calculated by fire time history analysis.A collapse time fragility curve is fitted according to the calculated collapse times of the samples.A reliability index of the collapse time is used as a quantitative standard to evaluate the collapse performance of a steel frame in a fire.Finally,this method is applied to analyse the collapse time fragility of an eight-storey 3 D steel frame structure under different compartment fire scenarios and fire protection levels.According to the collapse time fragility curve,the effects of the different fire scenarios and protection levels on the collapse resistance of the structure under fire are evaluated.
文摘The two compartment model with variable extracellular volume is presented and solved by using both perturbation and analytical method. The computation for both creatinine and urea show that the perturbation solution is not only simple but also accurate enough and is a good substitute for the more exact analytical solution.
文摘Strictosidine synthase (STR) is a key enzyme involved in the biosynthesis of terpenoid indole alkaloids (TIA) by condensing tryptamine and secologanin into strictosidine. The transgenic tobacco plants targeting STR to subcellular compartments were established to express STR in chloroplast, vacuole and endoplasmic reticulum (ER) by the tobacco stable transformation. It was shown that STR was effectively expressed in the above subcellular compartments by Western blot analysis and STR enzymatic assay. In vitro , STR enzymatic assay was measured indirectly by fluorimetrically detecting depletion of tryptamine feeding on secologanin in the reaction mixture. The tryptamine were completely depleted by STR in the crude extract of leaves of transgenic tobacco plants targeting and expressing STR in the chloroplast, vacuole and ER, which ascertained the STR functionally targeted to the three subcellular compartments. To confirm STR correct targeting and expressing in chloroplast, the chloroplasts were isolated and the fractions of purified chloroplasts were analyzed by Western blot. The hypothesis of STR correct targeting to the chloroplast was tested. The results have implications on our understanding of the complex intracellular trafficking in metabolic intermediates of TIA biosynthesis.
基金supported by the National Natural Science Foundation of China(NSFC/RGC/JRF N_HKU735/21)Research Grant Council of Hong Kong,China(17102120,17108821,17103922,C1024-22GF,C7074-21G)+1 种基金Health and Medical Research Fund(HMRF 09200966)(to CSWL)FRQS Postdoctoral Fellowship(to AHKF).
文摘Dendritic spines are small protrusions along dendrites that contain most of the excitatory synapses in principal neurons,playing a crucial role in neuronal function by creating a compartmentalized environment for signal transduction.The plasticity of spine morphologies provides a tunable handle to regulate calcium signal dynamics,allowing rapid regulation of protein expression necessary to establish and maintain synapses(Cornejo et al.,2022).If excitatory inputs were to be located primarily on dendritic shafts,dendrites would frequently short-circuit,preventing voltage signals from propagating(Cornejo et al.,2022).It is thus not surprising that the structural plasticity of dendritic spines is closely linked to synaptic plasticity and memory formation(Berry and Nedivi,2017).While comprehensive in vitro studies have been conducted,in vivo studies that directly tackle the mechanism of dendritic transport and translation in regulating spine plasticity spatiotemporally are limited.
文摘AIM: To study retrospectively the influence of intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS) in patients with early acute pancreatitis (AP) (during the first week after admission) on physiological functions, and the association of the presence of IAH/ACS and outcome. METHODS: Patients (n = 74) with AP recruited in this study were divided into two groups according to intra-abdominal pressure (IAP) determined by indirect measurement using the transvesical route via Foley bladder catheter during the first week after admission. Patients (n = 44) with IAP ≥ 12 mmHg were assigned in IAH group, and the remaining patients (n = 30) with IAP < 12 mmHg in normal IAP group. For analysis of the influence of IAH/ACS on organ function and outcome, the physiological parameters and the occurrence of organ dysfunction during intensive care unit (ICU) stay were recorded, as were the incidences of pancreatic infection and in-hospital mortality. RESULTS: IAH within the first week after admission was found in 44 patients (59.46%). Although the APACHE Ⅱ scores on admission and the Ranson scores within 48 h after hospitalization were elevated in IAH patients in early stage, they did not show the statistically significant differences from patients with normal IAP within a week after admission (16.18 ± 3.90 vs 15.70 ± 4.25, P = 0.616; 3.70 ± 0.93 vs 3.47 ± 0.94, P = 0.285, respectively). ACS in early AP was recorded in 20 patients (27.03%). During any 24-h period ofthe first week after admission, the recorded mean IAP correlated significantly with the Marshall score calculated at the same time interval in IAH group (r = 0.635, P < 0.001). Although ACS patients had obvious amelioration in physiological variables within 24 h after decompression, the incidences of pancreatitic infection, septic shock, multiple organ dysfunction syndrome (MODS) and death in the patients with ACS were significantly higher than that in other patients without ACS (pancreatitic infection: 60.0% vs 7.4%, P < 0.001; septic shock: 70.0% vs 11.1%, P < 0.001; MODS: 90.0% vs 31.5%, P < 0.001; mortality: 75.0% vs 3.7%, P < 0.001). CONCLUSION: IAH/ACS is a frequent finding in patients admitted to the ICU because of AP. Patients with IAP at approximately 10-12 mmHg and early signs of changes in physiologic variables should be seriously considered for urgent decompression to improve survival.
文摘AIM： To assess the value of widely used clinical scores in the early identification of acute pancreatitis （AP） patients who are likely to suffer from intra-abdominal hypertension （IAH） and abdominal compartment syndrome （ACS）.METHODS： Patients （η = 44） with AP recruited in this study were divided into two groups （ACS and non-ACS） according to intra-abdominal pressure （IAP） determined by indirect measurement using the transvesical route via Foley bladder catheter. On admission and at regular intervals, the severity of the AP and presence of organ dysfunction were assessed utilizing different multifactorial prognostic systems： Glasgow-Imrie score, Acute Physiology and Chronic Health Evaluation Ⅱ （APACHE-Ⅱ） score, and Multiorgan Dysfunction Score （MODS）. The diagnostic performance of scores predicting ACS development, cut-off values and specificity and sensitivity were established using receiver operating characteristic （ROC） curve analysis.RESULTS： The incidence of ACS in our study population was 19.35%. IAP at admission in the ACS group was 22.0 （18.5-25.0） mmHg and 9.25 （3.0-12.4） mmHg in the non-ACS group （P 〈 0.01）. Univariate statistical analysis revealed that patients in the ACS group had significantly higher multifactorial clinical scores （APACHE Ⅱ, Glasgow-Imrie and MODS） on admission and higher maximal scores during hospitalization （P 〈 0.01）. ROC curve analysis revealed that APACHE Ⅱ, Glasgow-Imrie, and MODS are valuable tools for early prediction of ACS with high sensitivity and specificity, and that cut-off values are similar to those used for stratification of patients with severe acute pancreatitis （SAP）.CONCLUSION： IAH and ACS are rare findings in patients with mild AR Based on the results of our study we recommend measuring the IAP in cases when patients present with SAP （APACHE Ⅱ 〉 7; MODS 〉 2 or Glasgow-Imrie score 〉 3）.
文摘AIM: To investigate the therapeutic effect of traditional Chinese traditional medicines Da Cheng Qi Decoction (Timely-Purging and Yin-Preserving Decoction) and Glauber's salt combined with conservative measures on abdominal compartment syndrome (ACS) in severe acute pancreatitis (SAP) patients. METHODS: Eighty consecutive SAP patients, admitted for routine non-operative conservative treatment, were randomly divided into study group and control group (40 patients in each group). Patients in the study group received Da Cheng Qi Decoction enema for 2 h and external use of Glauber's salt, once a day for 7 d. Patients in the control group received normal saline (NS) enema. Routine non-operative conservative treatments included non-per os nutrition (NPON), gastrointestinal decompression, life support, total parenteral nutrition (TPN), continuous peripancreatic vascular pharmaceutical infusion and drug therapy. Intra-cystic pressure (ICP) of the two groups was measured during treatment. The effectiveness and outcomes of treatment were observed and APACHE Ⅱ scores were applied in analysis. RESULTS: On days 4 and 5 of treatment, the ICP was lower in the study group than in the control group(P < 0.05). On days 3-5 of treatment, acute physiology and chronic health evaluation Ⅱ (APACHE Ⅱ) scores for the study and control groups were significantly different (P < 0.05). Both the effectiveness and outcome of the treatment with Da Cheng Qi Decoction on abdominalgia, burbulence relief time, ascites quantity, cyst formation rate and hospitalization time were quite different between the two groups (P < 0.05). The mortality rate for the two groups had no significant difference. CONCLUSION: Da Cheng Qi Decoction enema and external use of Glauber's salt combined with routine non-operative conservative treatment can decrease the intra-abdominal pressure (IAP) of SAP patients and have preventive and therapeutic effects on abdominal compartment syndrome of SAP.
基金supported by the Medical Scientific Research Foundation of Zhejiang Province, China (No. 2010KYA109)the Administration of Traditional Chinese Medicine of Zhejiang Province, China (No. 2010ZB080)
文摘This survey was designed to clarify the current understanding and clinical management of intra-abdominal hypertension （IAH）/abdominal compartment syndrome （ACS） among intensive care physicians in tertiary Chinese hospitals. A postal twenty-question questionnaire was sent to 141 physicians in different intensive care units （ICUs）. A total of 108 （76.6%） questionnaires were returned. Among these, three quarters worked in combined medical-surgical ICUs and nearly 80% had primary training in internal or emergency medicine. Average ICU beds, annual admission, ICU length of stay, acute physiology and chronic health evaluation （APACHE）II score, and mortality were 18.2 beds, 764.5 cases, 8.3 d, 19.4, and 21.1%, respectively. Of the respondents, 30.6% never measured intra-abdominal pressure （IAP）. Although the vast majority of the ICUs adopted the exclusively transvesicular method, the over- whelming majority （88.0%） only measured lAP when there was a clinical suspicion of IAH/ACS and only 29.3% measured either often or routinely. Moreover, 84.0% used the wrong priming saline volume while 88.0% zeroed at reference points which were not in consistence with the standard method for lAP monitoring recommended by the World Society of Abdominal Compartment Syndrome. ACS was suspected mainly when there was a distended ab- domen （92%）, worsening oliguria （80%）, and increased ventilatory support requirement （68%）. Common causes for IAH/ACS were ＂third-spacing from massive volume resuscitation in different settings＂ （88%）, ＂intra-abdominal bleeding＂, and ＂liver failure with ascites＂ （52% for both）. Though 60% respondents would recommend surgical decompression when the lAP exceeded 25 mmHg, accompanied by signs of organ dysfunction, nearly three quarters of re- spondents preferred diuresis and dialysis. A total of 68% of respondents would recommend paracentesis in the treatment for ACS. In conclusion, urgent systematic education is absolutely necessary for most intensive care physicians in China to help to establish clear diagnostic criteria and appropriate management for these common, but life-threatening, diseases.
文摘Intra-abdominal hypertension(IAH)and abdominal compartment syndrome are well recognized entities among surgical patients.Nevertheless,a number of prospective and retrospective observational studies have shown that IAH is prevalent in about half of the critically ill patients in the medical intensive care units(ICU)and has been widely recognized as an independent risk factor for mortality.It is alarming to note that many members of the critical care team in medical ICU are not aware of the consequences of untreated IAH and the delay in making the diagnosis leads to increased morbidity and mortality.Frequently it is underdiagnosed and undertreated in this patient population.Elevated intraabdominal pressure decreases the blood flow to the kidneys and other abdominal viscera and also results in reduced cardiac output and difficulties in ventilating the patient because of increased intrathoracic pressure.When intraabdominal hypertension is not promptly recognized and treated,it leads to abdominal compartment syndrome,multiorgan dysfunction syndrome and death.Large volume fluid resuscitation is very common in medical ICU patients presenting with sepsis,shock and other inflammatory conditions like pancreatitis and it is one of the major risk factors for the development of intra-abdominal hypertension.This article presents an overview of the epidemiology,definitions,risk factors,pathophysiology and management of IAH and abdominal compartment syndrome in critically ill medical ICU patients.
文摘AIM： To study the effect of combined indwelling catheter, hemofiltration, respiration support and traditional Chinese medicine （e.g. Dahuang） in treating abdominal compartment syndrome of fulminant acute pancreatitis. METHODS： Patients with fulminant acute pancreatitis were divided randomly into 2 groups of combined indwelling catheter celiac drainage and intra-abdominal pressure monitoring and routine conservative measures group （group 1） and control group （group 2）. Routine non-operative conservative treatments including hemofiltration, respiration support, gastrointestinal TCM ablution were also applied in control group patients. Effectiveness of the two groups was observed, and APACHE Ⅱ scores were applied for analysis. RESULTS： On the second and fifth days after treatment, APACHE Ⅱ scores of group 1 and 2 patients were significantly different. Comparison of effectiveness （abdominalgia and burbulence relief time, hospitalization time） between groups 1 and 2 showed significant difference, as well as incidence rates of cysts formation. Mortality rates of groups 1 and 2 were 10.0% and 20.7%, respectively. For patients in group 1, celiac drainage quantity and intra-abdominal pressure, and hospitalization time were positively correlated （r = 0.552, 0.748, 0.923, P 〈 0.01） with APACHE Ⅱ scores. CONCLUSION： Combined indwelling catheter celiac drainage and intra-abdominal pressure monitoring, short veno-venous hemofiltration （SVVH）, gastrointestinal TCM ablution, respiration support have preventive and treatment effects on abdominal compartment syndrome of fulminant acute pancreatitis.
基金This research is supported by the NNSF of China (19971066)
文摘The SEIR epidemic model studied here includes constant inflows of new susceptibles, exposeds, infectives, and recovereds. This model also incorporates a population size dependent contact rate and a disease-related death. As the infected fraction cannot be eliminated from the population, this kind of model has only the unique endemic equilibrium that is globally asymptotically stable. Under the special case where the new members of immigration are all susceptible, the model considered here shows a threshold phenomenon and a sharp threshold has been obtained. In order to prove the global asymptotical stability of the endemic equilibrium, the authors introduce the change of variable, which can reduce our four-dimensional system to a three-dimensional asymptotical autonomous system with limit equation.
基金supported partially by funds from the NIH (RO1AR054385, P30GM103333)
文摘Osteocytes, the most abundant bone cells, form an interconnected network in the lacunar-canalicular pore system （LCS） buried within the mineralized matrix, which allows osteocytes to obtain nutrients from the blood supply, sense external mechanical signals, and communicate among themselves and with other cells on bone surfaces. In this study, we examined key features of the LCS network including the topological parameter and the detailed structure of individual connections and their variations in cortical and cancellous compa~ tments, at different ages, and in two disease conditions with altered mechanosensing （perlecan deficiency and diabetes）. LCS network showed both topological stability, in terms of conservation of connectivity among osteocyte lacunae （similar to the ＂nodes＂ in a computer network）, and considerable variability the pericellular annular fluid gap surrounding lacunae and canaliculi （similar to the ＂bandwidth＂ of individual links in a computer network）. Age, in the range of our study （15-32 weeks）, affected only the pericellular fluid annulus in cortical bone but not in cancellous bone. Diabetes impacted the spacing of the lacunae, while the perlecan deficiency had a profound influence on the pericellular fluid annulus. The LCS network features play important roles in osteocyte signaling and regulation of bone growth and adaptation.
文摘Acute compartment syndrome(ACS) of the thigh following primary total hip arthroplasty(THA) is a highly uncommon complication and has not yet been reported before with regards to the anterior approach through the anterior supine interval. We present a case of a 69-year-old male patient with a history of stroke, who developed ACS of the thigh after elective THA while using therapeutic low molecular weight heparin as bridging for regular oral anticoagulation. ACS pathogenesis, diagnostic tools, treatment and relevant literature are discussed. The patient's ACS was recognized in time and treated by operative decompression with fasciotomy of the anterior compartment. Follow-up did not show any neurological deficit or soft-tissue damage.
文摘Abdominal compartment syndrome(ACS)develops when organ failure arises secondary to an increase in intraabdominal pressure.The abdominal pressure is determined by multiple factors such as blood pressure,abdominal compliance,and other factors that exert a constant pressure within the abdominal cavity.Several conditions in the critically ill may increase abdominal pressure compromising organ perfusion that may lead to renal and respiratory dysfunction.Among surgical and trauma patients,aggressive fluid resuscitation is the most commonly reported risk factor to develop ACS.Other conditions that have also been identified as risk factors are ascites,hemoperitoneum,bowel distention,and large tumors.All patients with abdominal trauma possess a higher risk of developing intra-abdominal hypertension(IAH).Certain surgical interventions are reported to have a higher risk to develop IAH such as damage control surgery,abdominal aortic aneurysm repair,and liver transplantation among others.Close monitoring of organ function and intra-abdominal pressure(IAP)allows clinicians to diagnose ACS rapidly and intervene with target-specific management to reduce IAP.Surgical decompression followed by temporary abdominal closure should be considered in all patients with signs of organ dysfunction.There is still a great need for more studies to determine the adequate timing for interventions to improve patient outcomes.
文摘Intra-abdominal hypertension(IAH)and abdominal compartment syndrome(ACS)play a pivotal role in the pathophysiology of severe acute pancreatitis(SAP)and contribute to new-onset and persistent organ failure.The optimal management of ACS involves a multi-disciplinary approach,from its early recognition to measures aiming at an urgent reduction of intra-abdominal pressure(IAP).A targeted literature search from January 1,2000,to November 30,2022,revealed 20 studies and data was analyzed on the type and country of the study,patient demographics,IAP,type and timing of surgical procedure performed,post-operative wound management,and outcomes of patients with ACS.There was no randomized controlled trial published on the topic.Decom-pressive laparotomy is effective in rapidly reducing IAP(standardized mean difference=2.68,95%confidence interval:1.19-1.47,P<0.001;4 studies).The morbidity and complications of an open abdomen after decompressive laparotomy should be weighed against the inadequately treated but,potentially lethal ACS.Disease-specific patient selection and the role of less-invasive decompressive measures,like subcutaneous linea alba fasciotomy or component separation techniques,is lacking in the 2013 consensus management guidelines by the Abdominal Compartment Society on IAH and ACS.This narrative review focuses on the current evidence regarding surgical decompression techniques for managing ACS in patients with SAP.However,there is a lack of high-quality evidence on patient selection,timing,and modality of surgical decompression.Large prospective trials are needed to identify triggers and effective and safe surgical decompression methods in SAP patients with ACS.
