Objective: To study the effect of surface configuration on the corrosion resistance and bacterium accumulation of pure Titanium(Ti) when used in oral environment. Methods: Six edentulous volunteers with healthy oral m...Objective: To study the effect of surface configuration on the corrosion resistance and bacterium accumulation of pure Titanium(Ti) when used in oral environment. Methods: Six edentulous volunteers with healthy oral mucosa participated in an in vivo study. Two kinds of pure Ti testing pieces with plane and wrinkly surface were fixed in the polished surface of upper complete dentures. After 6-month wearing, dynamic polarization curves were traced with electrochemical method and the amount and species of bacterium adhered on pure Ti were examined. Results: ① Ep and Ip of specimen in oral cavity was higher than that left in air, which meant corrosion resistance falling. Compared to plane one, Ecorr of wrinkly specimen was more positive and Ep and Ip were more higher, so its corrosion resistance reduced. ② Individual difference put a significant influence on amount of bacterium adhered on pure Titanium, but had no relation to species of bacterium. To the same patient, wrinkly samples collected more bacterium than plane ones, and exhibited G - coccus beside G + coccus. Conclusion: From the perspective of corrosion behavior and benefit to periodontal tissue, wrinkly surface should not be adopted when pure Ti prosthesis is made,especially on connector part of denture.展开更多
Gestational diabetes mellitus has been identified as a major complication of <span style="font-family:Verdana;">pregnancies and has remained a major cause of perinatal morbidity and</span><spa...Gestational diabetes mellitus has been identified as a major complication of <span style="font-family:Verdana;">pregnancies and has remained a major cause of perinatal morbidity and</span><span style="font-family:Verdana;"> mortality, as well as maternal morbidity. Lipid abnormalities significantly contribute to the increased risk of cardiovascular disease and other morbidities in diabetics. One of the benefits of regular exercise is a reduction in cardiovascular risk factors through the improvement of the lipid profile and reduction of hypertension. This study investigated the effect of aerobic training on the cholesterol level of women with gestational diabetes. Thirty-four (34) women who met the inclusion criteria for this study were randomized into Exercise and Control groups. Exercise group participated in structured exercise programme, 3 sessions a week for 8 weeks with each session lasting a maximum of 60 minutes while the Control group did not participate in any form of structured exercise programme for the period of the study. Data were collected at baseline, at 4th week and at 8th week into the exercise programme. Thirty (30) of the participants completed the study and so only their data were analysed using Repeated Measure ANOVA and Independent t-test. The result showed significant changes in the total cholesterol (F[2, 28]) = 268.316, P</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">=</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">0.001), of the Exercise group compared to the control. Independent t-test used to compare the lipid profile of the Experimental and Control groups showed significant difference between the means of the 2 groups at week 4 (total cholesterol (t(28) 2.164, P = </span><span style="font-family:Verdana;">0</span><span style="font-family:Verdana;">.039, triglyceride [t(28) 3.146 P</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">= </span><span style="font-family:Verdana;">0</span><span style="font-family:Verdana;">.004] and week 8 (total cholesterol t(28) 4.596, P</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">= </span><span style="font-family:Verdana;">0</span><span style="font-family:Verdana;">.001, triglyceride t(28) 5.534, P</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">=</span><span style="font-family:Verdana;"> 0</span><span style="font-family:Verdana;">.001) but not at baseline (total cholesterol t(28) -</span><span style="font-family:;" "=""><span style="font-family:Verdana;">901, P</span></span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">= </span><span style="font-family:Verdana;">0</span><span style="font-family:Verdana;">.375, triglyceride t(28) 1.612, P = </span><span style="font-family:Verdana;">0</span><span style="font-family:;" "=""><span style="font-family:Verdana;">.118). It was concluded that structured aerobic </span><span style="font-family:Verdana;">exercises may have positive effect on the components of lipid profile in</span><span style="font-family:Verdana;"> women with gestational diabetes.</span></span>展开更多
Objective： To study the effect of surface configuration and roughness on the corrosion resistance of pure Titanium （Ti） after used in oral environment for half a year. Methods ：Three edentulous volunteers with hea...Objective： To study the effect of surface configuration and roughness on the corrosion resistance of pure Titanium （Ti） after used in oral environment for half a year. Methods ：Three edentulous volunteers with healthy oral mucosa participated in an in vivo study. Four kinds of pure Ti testing pieces with different surface roughness were fixed in the polished surface of upper complete dentures and the other in the tissue surface of the dentures. After 6-month wearing the denture, dynamic polarization curves were traced with electrochemical method. Results：Ep and Ip of specimen used in oral cavity was higher than that left in air,which meant corrosion resistance falling. Compared to plane one ,Ecorr of wrinkly specimen was more positive,and Ep and Ip were more higher,so its corrosion resistance reduced. With the increase of surface roughness,Ep and Ip increased from 0.937 V and 1.810μA （Group Ⅱ） to 1.701 V and 2.252μA （Group Ⅳ）respectively,there was even no passivation in Group Ⅲ （which was the most coarse）,so proneness to corrosion enhanced. For specimen with the same surface roughness ,Ep and Ip of Group Ⅳ （1.701 V and 2.252 μA respectively） ,which was placed on polished surface of denture base,was higher than that on tissue surface（Group V , 1. 304 V, 1. 946μA）. Conclusion： From the perspective of corrosion behavior, wrinkly surface should not be adopted when pure Ti prosthesis is used,and surface roughness on the polishing surface of pure Ti prosthesis should be paid more attention,especially on clasps and connectors, where there is often more force to be exerted.展开更多
Background: The World Health Organization adopted Artenisinin based combination therapy (ACT) for the treatment of uncomplicated malaria in endemic regions. The efficacy of ACT in malaria treatment must have prompted ...Background: The World Health Organization adopted Artenisinin based combination therapy (ACT) for the treatment of uncomplicated malaria in endemic regions. The efficacy of ACT in malaria treatment must have prompted this choice. There’s need to protect the ACT from plasmodial resistance. Hence, clinical scaling up of ACT program is needed. This entails continued assessment, monitoring and evaluation of the effectiveness of component drugs in endemic areas. Purpose: This study revisited the evaluation of the effectiveness of artemether-lumefantrine combination (ALC) in the treatment of uncomplicated malaria in Elele, Nigeria. Method: The study was conducted in Elele, a malaria endemic area in Rivers State, Nigeria. This was a facility based descriptive, cross sectional study at Madonna University Teaching Hospital (MUTH) Elele using simple sampling technique. Qualitative and quantitative data were collected. 100 patients who consented to the study were recruited in the outpatient clinic using semi structured questionnaires as part of study instrument. Inclusion criteria were having a body temperature of ≥37.5°C, symptoms of malaria, positive parasitemia, non ingestion of antimalarial in the past 2 weeks, etc. MUTH ethics committee gave ethical clearance. Patient recruitment following consent commenced with their symptoms and signs recorded at presentation while disappearance of the same was determined following drug ingestion on days 2/4/6/8/10 and 14. The data gotten was analyzed by tallying the responses to get the frequencies using SPSS 16.0 version and Microsoft excel tools. The student t-test was used to calculate the P-value, values < 0.05 was considered statistically significant. Results: Most of the patients knew mosquitoes as the mode of malaria transmission (70%). The ACT is known and used by these patients: artesunate/amodiaquine: 41 (41%);artesunate/lumefantrine: 40 (40%);artesunate/sulphadoxine-pyrimethamine: 38(38%);artesunate/mefloquine: 20 (20%). Fever was the predominant presenting symptom, 92% followed by body weakness (90%);headache (85%);malaise (80%);loss of appetite (80%);nausea (72%);vomiting (70%);abdominal pains (50%). Others were: pallor (30%);hepatomegally (20%);splenomegally (20%);chills (20%);rigor (20%). By day 10 of therapy, fever, vomiting and abdominal pains had disappeared in all patients, some patients still had mild: body weakness 40%;headache 2%;malaise 24%;loss of appetite 20% and nausea 10%. Day 14 recorded no symptoms in all patients. There was effective clinical response (ECR) by day 14. Conclusion: This study hereby reaffirms the efficacy and effectiveness of Artemether-lumefantrine Combination in the treatment of uncomplicated malaria in Elele, Nigeria. The need to fill the existing knowledge gap of monitoring and evaluation of ACT in rural endemic areas has been done by this study.展开更多
Sickle cell anemia (SCA) patients are reported with infertility and low rate of pregnancies. This is associated with wide range of reproductive issues that are still relevant because of the complications and problems ...Sickle cell anemia (SCA) patients are reported with infertility and low rate of pregnancies. This is associated with wide range of reproductive issues that are still relevant because of the complications and problems of the disease that still persist till date. This study was carried out to establish the secretion pattern of the sex hormones (Progesterone and Estradiol) in the three trimesters of pregnant sickle cell disease subjects in the Niger Delta Region, south of Nigeria. The study included twenty (20) pregnant sickle cell anemia subjects with average age of 27.4 years and twenty (20) apparently healthy (Hemoglobin AA) subjects with average age of 28.2 years. Their samples collection started when they registered for antenatal care at the clinics within the first trimester of pregnancy. The Enzyme Linked Immunosorbent assay (ELISA) method was used in the measurement of the hormones in the plasma of the subjects. The result showed a statistical significant reduction (P < 0.05) in the values of the hormones in the three trimesters obtained for the sickle cell disease (SCD) subjects when compared with apparently healthy subjects with the same age range. Statistical analysis showed a strong positive correlation ((r = 0.8151 for Estradiol and r = 0.8793) for Progesterone) between the secretion of the sex hormones, in the sickle cell subjects and the control. The result is attributed to the sickle cell gene abnormality and the treatment of SCA that affects the endocrine system by inhibiting the production of gonadotropins from the pituitary gland. The SCD itself does not directly damage the reproductive system;however it can affect other systems which will eventually cause harm to the reproductive system. The study concluded that the sickle cell anemia patients require the administration of the hormone drugs during pregnancy to prevent to a certain extent, complications arising from hormonal imbalance.展开更多
This was a Pre-test/Post-test research designed to study the acute heart rate response of pregnant women to aerobic dance exercise. Twenty four (24) pregnant women with no complications participated in this study. HR ...This was a Pre-test/Post-test research designed to study the acute heart rate response of pregnant women to aerobic dance exercise. Twenty four (24) pregnant women with no complications participated in this study. HR increased significantly after 30 minutes exercise [7.292, P = 0.004 (P < 0.05)] and then decreased significantly again after 30 minutes rest, post exercise [10.00, P = 0.0001 (P < 0.05)]. The heart rate normalised after 30 minutes rest, showing no significant difference from the pre-exercise value [2.708, P = 0.517 (P > 0.05)]. Moderate intensity Aerobic Dance Exercise may not precipitate adverse acute cardiorespiratory response in pregnant women with no complications.展开更多
Background: Healthcare workers are challenged by an imposing group of occupational hazards. These hazards include exposure to biological and non-biological hazards like ionizing radiation, stress, injury, infectious a...Background: Healthcare workers are challenged by an imposing group of occupational hazards. These hazards include exposure to biological and non-biological hazards like ionizing radiation, stress, injury, infectious agents, and chemicals. The aim of this study was to assess common occupational hazards among health workers at the Department of Health Services (DHS), Federal University of Technology, Owerri. Methods: A hospital-based cross-sectional study design was employed for the study, and a self-administered questionnaire was used for data collection. The SPSS Version 22.0 software was used for the analysis of the descriptive statistics obtained from the study. This study included both clinical and non-clinical health workers. A purposive sampling technique was used in recruiting a total of 94 respondents who participated in the study from September 2020 to April 2021. Results: A total of 94 respondents who participated in the study and among the participants, 33.3% (31) of the respondents were aged 31 - 40 years, and the majority of the health workers, 43.6% (41) had stayed between 1 - 5 years. Also, 92.6% (87) of the health workers have heard of occupational hazards. The study showed that 84.0% (79) of health workers had good knowledge of common occupational hazards. Biological hazards among health workers are 47.9% (45) cuts and wounds, 29.8% (28) direct contact with contaminated specimens/hazardous materials, and 26.6% (26) sharp related injuries, while for non-biological hazards, 44.7% (42) have slipped, tripped or fallen, and 35.1% (33) have been stressed. Common safety measures include 86.2% (81) washing their hands regularly;78.7% (74) using hand gloves;and 85.1% (80) agreeing they use face masks. Conclusion: Despite good knowledge of occupational hazards, participants at DHS were faced with certain hazards. It is recommended that the university, government, and policymakers revise and implement actions to provide health workers at DHS with equipment to encourage safety in work activity.展开更多
Objective: The aim of this experiment is to study the effect of three methods of surface modification on the corrosion resistance of commercial pure Titanium when used in oral environment for half a year.Method:48 spe...Objective: The aim of this experiment is to study the effect of three methods of surface modification on the corrosion resistance of commercial pure Titanium when used in oral environment for half a year.Method:48 specimens of pure titanium were made and divided into four groups randomly, one group was selected randomly as Group I (control group), the other three groups were treated by three methods of surface modification individually, GroupⅡ:heating oxidation in air(400℃,30min.), GroupⅢ:anodization (45 volts, 10 min.),GroupⅣ:TiN coating(firing temperature 200℃ , total coating time 62min.). Six edentulous volunteers with healthy oral mucosa participated in the in vivo study. One testing piece from each group was selected and fixed in the polished surface of upper complete dentures. Dynamic polarization curves were traced with electrochemical method after the specimens were placed either in oral cavity or in air for 6 months. Results: After all specimens were used, Ecorr altered in every group , Ecorr from high to low were in turn: TiN coating group>heating oxidation group> anodization group>control group, no obvious passive potential Ep and Ip was found in control group. Heating oxidation in air exhibited similar Ep to anodization, but Ip was remarkably lower than that of anodization; TiN coating showed obviously different polarization curves compared with heating-oxidation group and anodization group, Ecorr was positive, and no Ep and Ip was found. Conclusion: Under present experimental condition, all the three treatment methods could enhance corrosion resistance of pure titanium in oral environment, heating oxidation in air exhibited better resistance to corrode than anodization, TiN coating possessed the most excellent corrosion resistance, even after exposed in oral condition for 6 months, there was little change of corrosion resistance. Therefore TiN coating could be adopted to improve corrosion resistance of pure titanium in oral environment.展开更多
The objective of this study was to systematically review the literature about the use of the operating microscope in endodontics. It used sources of bibliographic cataloging electronically identified by MEDLINE via Pu...The objective of this study was to systematically review the literature about the use of the operating microscope in endodontics. It used sources of bibliographic cataloging electronically identified by MEDLINE via PubMed, LILACS, BBO and Scopus, using as descriptors: Endodontics, anatomy and microscopy. The selected articles were identified from the titles and abstracts, taking into consideration the following criteria: publications ranging from January 2001 to November 2012, case reports, published in an indexed journal, and publications in English language. The search showed 167 articles related to this topic, and these 21 articles met the inclusion criteria. These indicated that a higher magnification helps coronary access and the location of channels to identify and interpret the complexities of the anatomy of root canals, the removal of nuclei and intracoronary fractured instruments, to minimize trauma of surgeries in soft and hard tissues, and detect fractures and microfractures. It was found that its use has provided Endodontics with a significant improvement in vision of the operative field, offering better quality jobs and a higher success rate.展开更多
Background It is very difficult and relatively unpredictable to preserve and restore severely weakened pulpless roots. To provide much needed benefit basis for clinical practice, this study was carried out to analyze ...Background It is very difficult and relatively unpredictable to preserve and restore severely weakened pulpless roots. To provide much needed benefit basis for clinical practice, this study was carried out to analyze the stress distribution in weakened roots restored with different cements in combination with titanium alloy posts. Finite element analysis （FEA） was employed in the study. Methods A pseudo three-dimensional model of a maxillary central incisor with flared root canal, theoretically restored with titanium alloy posts in combination with different cements, was established. The analysis was performed by use of ANSYS software. The tooth was assumed to be isotropic, homogenous and elastic. A load of 100 N at an angle of 45° to the longitudinal axis was applied at the palatal surface of the crown. The distributions of stresses in weakened roots filled with cements of different elastic modulus were analyzed by the three-dimensional FEA model. Results Several stress trends were observed when the stress cloud atlas obtained in the study was analyzed. With the increase of the elastic modulus of cements from 1.8 GPa to 22.4 GPa, the stress values in dentin decreased from 39.58 MPa to 31.43 MPa and from 24.51 MPa to 20.76 MPa （respectively, for maximum principle stress values and Von Mises stress values）. When Panavia F and zinc phosphate cement were used, the stress peak values in dentin were very small with no significant difference observed, and the Von Mises stress values were 20.87 MPa and 20.76 MPa respectively. On the other hand, maximum principle stress value and Von Mises stress value in cement layer increased with the increase of the elastic modulus of cements. Conclusions The result of this study demonstrated that elastic modulus was indeed one of the important parameters to evaluate property of the cements. Our three-dimensional FEA model study also found that the cement with elastic modulus similar to that of dentin could reinforce weakened root and reduce the stress in dentin. Thus, it may be a better choice for the restoration of weakened roots in clinical practice.展开更多
Poloxamer 407,also known as Pluronic^(■)F127,is gaining interest in the cosmetic,biomedical and pharmaceutical fields for its biocompatibility,safety and thermo-sensitive properties.Ensuring sterility is critical in ...Poloxamer 407,also known as Pluronic^(■)F127,is gaining interest in the cosmetic,biomedical and pharmaceutical fields for its biocompatibility,safety and thermo-sensitive properties.Ensuring sterility is critical in clinical applications,and steriliza-tion is often preferred over aseptic processing.However,sterili-zation can impact the functional properties of the hydrogel.In this study,we investigate the effects of steam heat(121℃,20 min),dry heat(160℃,1 h),gamma irradiation(25 kGy)and electron beam(e-beam)irradiation(15 and 25 kGy)on a 30%w/v Poloxamer 407 hydrogel formulation.Our analysis encompasses gelling properties,pH,Fourier-transform infrared spectroscopy,gel permeation chromatography,small-angle X-ray scattering,rheology,swelling,degradation by-products and lactate dehydrogenase release of the sterilized hydrogels,comparing them to a non-sterile counterpart.We demonstrated that heat sterilization alters the hydrogel’s gelling and structural properties due to water evap-oration and oxidation under harsh temperature conditions,especially when applying the dry heat method.Gamma irradiation proved unsuitable,resulting in an acidic and cytotoxic hydrogel due to oxidative degradation.In contrast,e-beam irradiation preserves the hydrogel’s elasticity,gelling and structural properties while enhancing mechanical resilience and moderating swelling.Therefore,e-beam irradiation within the 15–25 kGy range appears to be the most suitable method for sterilizing a 30%w/v Poloxamer 407 hydrogel.展开更多
Phantom limb is a disabling neuropsychiatric condition among amputees resulting in pain and disturbance that impact their functions,quality of life,and autonomy.While pharmacological approaches appeared to be ineffec-...Phantom limb is a disabling neuropsychiatric condition among amputees resulting in pain and disturbance that impact their functions,quality of life,and autonomy.While pharmacological approaches appeared to be ineffec-tive,the emergence and integration of X-reality,including virtual reality,augmented reality,and mixed reality,might elevate the effectiveness of mirror therapy in managing phantom limb.The objective of this study is to review X-reality for managing phantom pain.A systematic search was conducted on PubMed,Scopus,Web of Science,PsycINFO,Embase,and CINAHL.Sixteen(n=16)studies containing 66 lower-limb and 53 upper-limb amputees were included for the review over the thematic framework of amputee characteristics and intervention designs,while thirteen(n=13)studies were further proceeded for the meta-analysis.We found eleven studies on virtual reality(n=11),four studies on marker-based augmented reality(n=4)and one study on mixed reality(n=1)with a total of 40 game/task themes involving,motor skills,motor control,and stimulus-sensing.Regardless,all these interventions adopted the movement representation strategies with different techniques.Overall,the X-reality interventions reduced the pain level of the amputees(mean difference:-2.30,95%CI,-3.38 to-1.22),especially the virtual reality subgroup(mean difference:-2.83,95%CI,-4.43 to-1.22).However,there were substantial heterogeneity and partially explained by the subgroup analysis on publication year.The strength of evidence was limited by case reports and case series in this review.展开更多
文摘Objective: To study the effect of surface configuration on the corrosion resistance and bacterium accumulation of pure Titanium(Ti) when used in oral environment. Methods: Six edentulous volunteers with healthy oral mucosa participated in an in vivo study. Two kinds of pure Ti testing pieces with plane and wrinkly surface were fixed in the polished surface of upper complete dentures. After 6-month wearing, dynamic polarization curves were traced with electrochemical method and the amount and species of bacterium adhered on pure Ti were examined. Results: ① Ep and Ip of specimen in oral cavity was higher than that left in air, which meant corrosion resistance falling. Compared to plane one, Ecorr of wrinkly specimen was more positive and Ep and Ip were more higher, so its corrosion resistance reduced. ② Individual difference put a significant influence on amount of bacterium adhered on pure Titanium, but had no relation to species of bacterium. To the same patient, wrinkly samples collected more bacterium than plane ones, and exhibited G - coccus beside G + coccus. Conclusion: From the perspective of corrosion behavior and benefit to periodontal tissue, wrinkly surface should not be adopted when pure Ti prosthesis is made,especially on connector part of denture.
文摘Gestational diabetes mellitus has been identified as a major complication of <span style="font-family:Verdana;">pregnancies and has remained a major cause of perinatal morbidity and</span><span style="font-family:Verdana;"> mortality, as well as maternal morbidity. Lipid abnormalities significantly contribute to the increased risk of cardiovascular disease and other morbidities in diabetics. One of the benefits of regular exercise is a reduction in cardiovascular risk factors through the improvement of the lipid profile and reduction of hypertension. This study investigated the effect of aerobic training on the cholesterol level of women with gestational diabetes. Thirty-four (34) women who met the inclusion criteria for this study were randomized into Exercise and Control groups. Exercise group participated in structured exercise programme, 3 sessions a week for 8 weeks with each session lasting a maximum of 60 minutes while the Control group did not participate in any form of structured exercise programme for the period of the study. Data were collected at baseline, at 4th week and at 8th week into the exercise programme. Thirty (30) of the participants completed the study and so only their data were analysed using Repeated Measure ANOVA and Independent t-test. The result showed significant changes in the total cholesterol (F[2, 28]) = 268.316, P</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">=</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">0.001), of the Exercise group compared to the control. Independent t-test used to compare the lipid profile of the Experimental and Control groups showed significant difference between the means of the 2 groups at week 4 (total cholesterol (t(28) 2.164, P = </span><span style="font-family:Verdana;">0</span><span style="font-family:Verdana;">.039, triglyceride [t(28) 3.146 P</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">= </span><span style="font-family:Verdana;">0</span><span style="font-family:Verdana;">.004] and week 8 (total cholesterol t(28) 4.596, P</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">= </span><span style="font-family:Verdana;">0</span><span style="font-family:Verdana;">.001, triglyceride t(28) 5.534, P</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">=</span><span style="font-family:Verdana;"> 0</span><span style="font-family:Verdana;">.001) but not at baseline (total cholesterol t(28) -</span><span style="font-family:;" "=""><span style="font-family:Verdana;">901, P</span></span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">= </span><span style="font-family:Verdana;">0</span><span style="font-family:Verdana;">.375, triglyceride t(28) 1.612, P = </span><span style="font-family:Verdana;">0</span><span style="font-family:;" "=""><span style="font-family:Verdana;">.118). It was concluded that structured aerobic </span><span style="font-family:Verdana;">exercises may have positive effect on the components of lipid profile in</span><span style="font-family:Verdana;"> women with gestational diabetes.</span></span>
文摘Objective： To study the effect of surface configuration and roughness on the corrosion resistance of pure Titanium （Ti） after used in oral environment for half a year. Methods ：Three edentulous volunteers with healthy oral mucosa participated in an in vivo study. Four kinds of pure Ti testing pieces with different surface roughness were fixed in the polished surface of upper complete dentures and the other in the tissue surface of the dentures. After 6-month wearing the denture, dynamic polarization curves were traced with electrochemical method. Results：Ep and Ip of specimen used in oral cavity was higher than that left in air,which meant corrosion resistance falling. Compared to plane one ,Ecorr of wrinkly specimen was more positive,and Ep and Ip were more higher,so its corrosion resistance reduced. With the increase of surface roughness,Ep and Ip increased from 0.937 V and 1.810μA （Group Ⅱ） to 1.701 V and 2.252μA （Group Ⅳ）respectively,there was even no passivation in Group Ⅲ （which was the most coarse）,so proneness to corrosion enhanced. For specimen with the same surface roughness ,Ep and Ip of Group Ⅳ （1.701 V and 2.252 μA respectively） ,which was placed on polished surface of denture base,was higher than that on tissue surface（Group V , 1. 304 V, 1. 946μA）. Conclusion： From the perspective of corrosion behavior, wrinkly surface should not be adopted when pure Ti prosthesis is used,and surface roughness on the polishing surface of pure Ti prosthesis should be paid more attention,especially on clasps and connectors, where there is often more force to be exerted.
文摘Background: The World Health Organization adopted Artenisinin based combination therapy (ACT) for the treatment of uncomplicated malaria in endemic regions. The efficacy of ACT in malaria treatment must have prompted this choice. There’s need to protect the ACT from plasmodial resistance. Hence, clinical scaling up of ACT program is needed. This entails continued assessment, monitoring and evaluation of the effectiveness of component drugs in endemic areas. Purpose: This study revisited the evaluation of the effectiveness of artemether-lumefantrine combination (ALC) in the treatment of uncomplicated malaria in Elele, Nigeria. Method: The study was conducted in Elele, a malaria endemic area in Rivers State, Nigeria. This was a facility based descriptive, cross sectional study at Madonna University Teaching Hospital (MUTH) Elele using simple sampling technique. Qualitative and quantitative data were collected. 100 patients who consented to the study were recruited in the outpatient clinic using semi structured questionnaires as part of study instrument. Inclusion criteria were having a body temperature of ≥37.5°C, symptoms of malaria, positive parasitemia, non ingestion of antimalarial in the past 2 weeks, etc. MUTH ethics committee gave ethical clearance. Patient recruitment following consent commenced with their symptoms and signs recorded at presentation while disappearance of the same was determined following drug ingestion on days 2/4/6/8/10 and 14. The data gotten was analyzed by tallying the responses to get the frequencies using SPSS 16.0 version and Microsoft excel tools. The student t-test was used to calculate the P-value, values < 0.05 was considered statistically significant. Results: Most of the patients knew mosquitoes as the mode of malaria transmission (70%). The ACT is known and used by these patients: artesunate/amodiaquine: 41 (41%);artesunate/lumefantrine: 40 (40%);artesunate/sulphadoxine-pyrimethamine: 38(38%);artesunate/mefloquine: 20 (20%). Fever was the predominant presenting symptom, 92% followed by body weakness (90%);headache (85%);malaise (80%);loss of appetite (80%);nausea (72%);vomiting (70%);abdominal pains (50%). Others were: pallor (30%);hepatomegally (20%);splenomegally (20%);chills (20%);rigor (20%). By day 10 of therapy, fever, vomiting and abdominal pains had disappeared in all patients, some patients still had mild: body weakness 40%;headache 2%;malaise 24%;loss of appetite 20% and nausea 10%. Day 14 recorded no symptoms in all patients. There was effective clinical response (ECR) by day 14. Conclusion: This study hereby reaffirms the efficacy and effectiveness of Artemether-lumefantrine Combination in the treatment of uncomplicated malaria in Elele, Nigeria. The need to fill the existing knowledge gap of monitoring and evaluation of ACT in rural endemic areas has been done by this study.
文摘Sickle cell anemia (SCA) patients are reported with infertility and low rate of pregnancies. This is associated with wide range of reproductive issues that are still relevant because of the complications and problems of the disease that still persist till date. This study was carried out to establish the secretion pattern of the sex hormones (Progesterone and Estradiol) in the three trimesters of pregnant sickle cell disease subjects in the Niger Delta Region, south of Nigeria. The study included twenty (20) pregnant sickle cell anemia subjects with average age of 27.4 years and twenty (20) apparently healthy (Hemoglobin AA) subjects with average age of 28.2 years. Their samples collection started when they registered for antenatal care at the clinics within the first trimester of pregnancy. The Enzyme Linked Immunosorbent assay (ELISA) method was used in the measurement of the hormones in the plasma of the subjects. The result showed a statistical significant reduction (P < 0.05) in the values of the hormones in the three trimesters obtained for the sickle cell disease (SCD) subjects when compared with apparently healthy subjects with the same age range. Statistical analysis showed a strong positive correlation ((r = 0.8151 for Estradiol and r = 0.8793) for Progesterone) between the secretion of the sex hormones, in the sickle cell subjects and the control. The result is attributed to the sickle cell gene abnormality and the treatment of SCA that affects the endocrine system by inhibiting the production of gonadotropins from the pituitary gland. The SCD itself does not directly damage the reproductive system;however it can affect other systems which will eventually cause harm to the reproductive system. The study concluded that the sickle cell anemia patients require the administration of the hormone drugs during pregnancy to prevent to a certain extent, complications arising from hormonal imbalance.
文摘This was a Pre-test/Post-test research designed to study the acute heart rate response of pregnant women to aerobic dance exercise. Twenty four (24) pregnant women with no complications participated in this study. HR increased significantly after 30 minutes exercise [7.292, P = 0.004 (P < 0.05)] and then decreased significantly again after 30 minutes rest, post exercise [10.00, P = 0.0001 (P < 0.05)]. The heart rate normalised after 30 minutes rest, showing no significant difference from the pre-exercise value [2.708, P = 0.517 (P > 0.05)]. Moderate intensity Aerobic Dance Exercise may not precipitate adverse acute cardiorespiratory response in pregnant women with no complications.
文摘Background: Healthcare workers are challenged by an imposing group of occupational hazards. These hazards include exposure to biological and non-biological hazards like ionizing radiation, stress, injury, infectious agents, and chemicals. The aim of this study was to assess common occupational hazards among health workers at the Department of Health Services (DHS), Federal University of Technology, Owerri. Methods: A hospital-based cross-sectional study design was employed for the study, and a self-administered questionnaire was used for data collection. The SPSS Version 22.0 software was used for the analysis of the descriptive statistics obtained from the study. This study included both clinical and non-clinical health workers. A purposive sampling technique was used in recruiting a total of 94 respondents who participated in the study from September 2020 to April 2021. Results: A total of 94 respondents who participated in the study and among the participants, 33.3% (31) of the respondents were aged 31 - 40 years, and the majority of the health workers, 43.6% (41) had stayed between 1 - 5 years. Also, 92.6% (87) of the health workers have heard of occupational hazards. The study showed that 84.0% (79) of health workers had good knowledge of common occupational hazards. Biological hazards among health workers are 47.9% (45) cuts and wounds, 29.8% (28) direct contact with contaminated specimens/hazardous materials, and 26.6% (26) sharp related injuries, while for non-biological hazards, 44.7% (42) have slipped, tripped or fallen, and 35.1% (33) have been stressed. Common safety measures include 86.2% (81) washing their hands regularly;78.7% (74) using hand gloves;and 85.1% (80) agreeing they use face masks. Conclusion: Despite good knowledge of occupational hazards, participants at DHS were faced with certain hazards. It is recommended that the university, government, and policymakers revise and implement actions to provide health workers at DHS with equipment to encourage safety in work activity.
基金This study was granted from the National Natural Science Foundation of China.Title of the grant-winning project:The Applied Basic Research on Surface Finishing for Titanium Dentures. January2002, serial number was :30171022.
文摘Objective: The aim of this experiment is to study the effect of three methods of surface modification on the corrosion resistance of commercial pure Titanium when used in oral environment for half a year.Method:48 specimens of pure titanium were made and divided into four groups randomly, one group was selected randomly as Group I (control group), the other three groups were treated by three methods of surface modification individually, GroupⅡ:heating oxidation in air(400℃,30min.), GroupⅢ:anodization (45 volts, 10 min.),GroupⅣ:TiN coating(firing temperature 200℃ , total coating time 62min.). Six edentulous volunteers with healthy oral mucosa participated in the in vivo study. One testing piece from each group was selected and fixed in the polished surface of upper complete dentures. Dynamic polarization curves were traced with electrochemical method after the specimens were placed either in oral cavity or in air for 6 months. Results: After all specimens were used, Ecorr altered in every group , Ecorr from high to low were in turn: TiN coating group>heating oxidation group> anodization group>control group, no obvious passive potential Ep and Ip was found in control group. Heating oxidation in air exhibited similar Ep to anodization, but Ip was remarkably lower than that of anodization; TiN coating showed obviously different polarization curves compared with heating-oxidation group and anodization group, Ecorr was positive, and no Ep and Ip was found. Conclusion: Under present experimental condition, all the three treatment methods could enhance corrosion resistance of pure titanium in oral environment, heating oxidation in air exhibited better resistance to corrode than anodization, TiN coating possessed the most excellent corrosion resistance, even after exposed in oral condition for 6 months, there was little change of corrosion resistance. Therefore TiN coating could be adopted to improve corrosion resistance of pure titanium in oral environment.
文摘The objective of this study was to systematically review the literature about the use of the operating microscope in endodontics. It used sources of bibliographic cataloging electronically identified by MEDLINE via PubMed, LILACS, BBO and Scopus, using as descriptors: Endodontics, anatomy and microscopy. The selected articles were identified from the titles and abstracts, taking into consideration the following criteria: publications ranging from January 2001 to November 2012, case reports, published in an indexed journal, and publications in English language. The search showed 167 articles related to this topic, and these 21 articles met the inclusion criteria. These indicated that a higher magnification helps coronary access and the location of channels to identify and interpret the complexities of the anatomy of root canals, the removal of nuclei and intracoronary fractured instruments, to minimize trauma of surgeries in soft and hard tissues, and detect fractures and microfractures. It was found that its use has provided Endodontics with a significant improvement in vision of the operative field, offering better quality jobs and a higher success rate.
文摘Background It is very difficult and relatively unpredictable to preserve and restore severely weakened pulpless roots. To provide much needed benefit basis for clinical practice, this study was carried out to analyze the stress distribution in weakened roots restored with different cements in combination with titanium alloy posts. Finite element analysis （FEA） was employed in the study. Methods A pseudo three-dimensional model of a maxillary central incisor with flared root canal, theoretically restored with titanium alloy posts in combination with different cements, was established. The analysis was performed by use of ANSYS software. The tooth was assumed to be isotropic, homogenous and elastic. A load of 100 N at an angle of 45° to the longitudinal axis was applied at the palatal surface of the crown. The distributions of stresses in weakened roots filled with cements of different elastic modulus were analyzed by the three-dimensional FEA model. Results Several stress trends were observed when the stress cloud atlas obtained in the study was analyzed. With the increase of the elastic modulus of cements from 1.8 GPa to 22.4 GPa, the stress values in dentin decreased from 39.58 MPa to 31.43 MPa and from 24.51 MPa to 20.76 MPa （respectively, for maximum principle stress values and Von Mises stress values）. When Panavia F and zinc phosphate cement were used, the stress peak values in dentin were very small with no significant difference observed, and the Von Mises stress values were 20.87 MPa and 20.76 MPa respectively. On the other hand, maximum principle stress value and Von Mises stress value in cement layer increased with the increase of the elastic modulus of cements. Conclusions The result of this study demonstrated that elastic modulus was indeed one of the important parameters to evaluate property of the cements. Our three-dimensional FEA model study also found that the cement with elastic modulus similar to that of dentin could reinforce weakened root and reduce the stress in dentin. Thus, it may be a better choice for the restoration of weakened roots in clinical practice.
基金supported by The Research Council of Norway(grant numbers 331752,332148)and(grant number 346292 to A.D.L.).
文摘Poloxamer 407,also known as Pluronic^(■)F127,is gaining interest in the cosmetic,biomedical and pharmaceutical fields for its biocompatibility,safety and thermo-sensitive properties.Ensuring sterility is critical in clinical applications,and steriliza-tion is often preferred over aseptic processing.However,sterili-zation can impact the functional properties of the hydrogel.In this study,we investigate the effects of steam heat(121℃,20 min),dry heat(160℃,1 h),gamma irradiation(25 kGy)and electron beam(e-beam)irradiation(15 and 25 kGy)on a 30%w/v Poloxamer 407 hydrogel formulation.Our analysis encompasses gelling properties,pH,Fourier-transform infrared spectroscopy,gel permeation chromatography,small-angle X-ray scattering,rheology,swelling,degradation by-products and lactate dehydrogenase release of the sterilized hydrogels,comparing them to a non-sterile counterpart.We demonstrated that heat sterilization alters the hydrogel’s gelling and structural properties due to water evap-oration and oxidation under harsh temperature conditions,especially when applying the dry heat method.Gamma irradiation proved unsuitable,resulting in an acidic and cytotoxic hydrogel due to oxidative degradation.In contrast,e-beam irradiation preserves the hydrogel’s elasticity,gelling and structural properties while enhancing mechanical resilience and moderating swelling.Therefore,e-beam irradiation within the 15–25 kGy range appears to be the most suitable method for sterilizing a 30%w/v Poloxamer 407 hydrogel.
基金The work was supported by the Research Institute for Sports Science and Technology(Reference number:P0043798)Internal Fund(Ref-erence number:P0035805)of the Hong Kong Polytechnic University.
文摘Phantom limb is a disabling neuropsychiatric condition among amputees resulting in pain and disturbance that impact their functions,quality of life,and autonomy.While pharmacological approaches appeared to be ineffec-tive,the emergence and integration of X-reality,including virtual reality,augmented reality,and mixed reality,might elevate the effectiveness of mirror therapy in managing phantom limb.The objective of this study is to review X-reality for managing phantom pain.A systematic search was conducted on PubMed,Scopus,Web of Science,PsycINFO,Embase,and CINAHL.Sixteen(n=16)studies containing 66 lower-limb and 53 upper-limb amputees were included for the review over the thematic framework of amputee characteristics and intervention designs,while thirteen(n=13)studies were further proceeded for the meta-analysis.We found eleven studies on virtual reality(n=11),four studies on marker-based augmented reality(n=4)and one study on mixed reality(n=1)with a total of 40 game/task themes involving,motor skills,motor control,and stimulus-sensing.Regardless,all these interventions adopted the movement representation strategies with different techniques.Overall,the X-reality interventions reduced the pain level of the amputees(mean difference:-2.30,95%CI,-3.38 to-1.22),especially the virtual reality subgroup(mean difference:-2.83,95%CI,-4.43 to-1.22).However,there were substantial heterogeneity and partially explained by the subgroup analysis on publication year.The strength of evidence was limited by case reports and case series in this review.
