GRADE建议通过检查95%可信区间(CI)为决定不精确性的最佳方法。在指南实际运用中,如果CI的上、下限值代表了真实效应,而临床实际情况与之不符时,必须降低证据质量级别(即对效应估计值的把握度)。除外当效应值很大且可信区间提示效应稳健...GRADE建议通过检查95%可信区间(CI)为决定不精确性的最佳方法。在指南实际运用中,如果CI的上、下限值代表了真实效应,而临床实际情况与之不符时,必须降低证据质量级别(即对效应估计值的把握度)。除外当效应值很大且可信区间提示效应稳健,而总样本量不大且事件数很少的情况,其他应考虑因不精确性而降低证据质量级别。作此决定时,可计算有足够检验效能的单个试验所需的病例数(定义为"最优信息样本量",即optimal information size,OIS)。对连续型变量,我们建议用类似方法,首先考虑可信区间上、下限值,再计算OIS。系统评价(SR)所需方法略有不同。如果95%CI不包括相对危险度(RR)为1,且总事件发生数或病例数超过OIS标准,则精确性良好。如果95%CI包括了明显获益或危害(我们建议以RR值<0.75或>1.25作粗标准),即使达到OIS要求,因不精确性而降低证据质量级别较恰当。展开更多
This article is to offer a concise review on the use of cytoreductive surgery （CRS） plus intraperitoneal hyperthermic chemotherapy （IPHC） for the treatment of peritoneal carcinomatosis （PC）. Traditionally, PC wa...This article is to offer a concise review on the use of cytoreductive surgery （CRS） plus intraperitoneal hyperthermic chemotherapy （IPHC） for the treatment of peritoneal carcinomatosis （PC）. Traditionally, PC was treated with systemic chemotherapy alone with very poor response and a median survival of less than 6 too. With the establishment of several phase Ⅱ studies, a new trend has been developed toward the use of CRS plus IPHC as a standard method for treating selected patients with PC, in whom sufficient cytoreduction could be achieved. In spite of the need for more high quality phase Ⅲ studies, there is now a consensus among many surgical oncology experts throughout the world about the use of this new treatment strategy as standard care for colorectal cancer patients with PC. This review summarizes the current status and possible progress in future.展开更多
AIM: To quantitatively summarize and appraise the available evidence of urea breath test(UBT) use to diagnose Helicobacter pylori(H. pylori) infection in patients with dyspepsia and provide pooled diagnostic accuracy ...AIM: To quantitatively summarize and appraise the available evidence of urea breath test(UBT) use to diagnose Helicobacter pylori(H. pylori) infection in patients with dyspepsia and provide pooled diagnostic accuracy measures.METHODS: We searched MEDLINE, EMBASE, Cochrane library and other databases for studies addressing the value of UBT in the diagnosis of H. pylori infection. We included cross-sectional studies that evaluated the diagnostic accuracy of UBT in adult patients with dyspeptic symptoms. Risk of bias was assessed using QUADAS(Quality Assessment of Diagnostic Accuracy Studies)-2 tool. Diagnostic accuracy measures were pooled using the random-effects model. Subgroup analysis was conducted by UBT type(13C vs 14C) and by measurement technique(Infrared spectrometry vs Isotope Ratio Mass Spectrometry).RESULTS: Out of 1380 studies identified, only 23 met the eligibility criteria. Fourteen studies(61%) evaluated 13 C UBT and 9 studies(39%) evaluated 14 C UBT. There was significant variation in the type of reference standard tests used across studies.Pooled sensitivity was 0.96(95%CI: 0.95-0.97) andpooled specificity was 0.93(95%CI: 0.91-0.94). Likelihood ratio for a positive test was 12 and for a negative test was 0.05 with an area under thecurve of 0.985. Meta-analyses were associated with a significant statistical heterogeneity that remained unexplained after subgroup analysis. The included studies had a moderate risk of bias.CONCLUSION: UBT has high diagnostic accuracy for detecting H. pylori infection in patients with dyspepsia. The reliability of diagnostic meta-analytic estimates however is limited by significant heterogeneity.展开更多
Nonalcoholic fatty liver disease(NAFLD)is quickly becoming one of the most prominent causes of liver disease worldwide.The increasing incidence of NAFLD is tied to the obesity epidemic and the subsequent metabolic der...Nonalcoholic fatty liver disease(NAFLD)is quickly becoming one of the most prominent causes of liver disease worldwide.The increasing incidence of NAFLD is tied to the obesity epidemic and the subsequent metabolic derangements brought along with it.Current efforts to elucidate the mechanism and causes of the disease have answered some questions,but much remains unknown about NAFLD.The aim of this article is to discuss the current knowledge regarding the pathogenesis of the disease,as well as the current and future diagnostic,preventative,and therapeutic options available to clinicians for the management of NAFLD.展开更多
Nosocomial infections or healthcare associated infections occur in patients under medical care.These infections occur worldwide both in developed and developing countries.Nosocomial infections accounts for 7% in devel...Nosocomial infections or healthcare associated infections occur in patients under medical care.These infections occur worldwide both in developed and developing countries.Nosocomial infections accounts for 7% in developed and 10% in developing countries.As these infections occur during hospital stay,they cause prolonged stay,disability,and economic burden.Frequently prevalent infections include central line-associated bloodstream infections,catheter-associated urinary tract infections,surgical site infections and ventilator-associated pneumonia.Nosocomial pathogens include bacteria,viruses and fungal parasites.According to WHO estimates,approximately 15% of all hospitalized patients suffer from these infections.During hospitalization,patient is exposed to pathogens through different sources environment,healthcare staff,and other infected patients.Transmission of these infections should be restricted for prevention.Hospital waste serves as potential source of pathogens and about 20%–25% of hospital waste is termed as hazardous.Nosocomial infections can be controlled by practicing infection control programs,keep check on antimicrobial use and its resistance,adopting antibiotic control policy.Efficient surveillance system can play its part at national and international level.Efforts are required by all stakeholders to prevent and control nosocomial infections.展开更多
Discharging dye contaminants into water is a major concern around the world.Among a variety of methods to treat dye-contaminated water,photocatalytic degradation has gained attention as a tool for treating the colored...Discharging dye contaminants into water is a major concern around the world.Among a variety of methods to treat dye-contaminated water,photocatalytic degradation has gained attention as a tool for treating the colored water.Herein,we review the recent advancements in photocatalysis for dye degradation in industrial effluents by categorizing photocatalyst materials into three generations.First generation photocatalysts are composed of single-component materials (e.g.,TiO2,ZnO,and CdS),while second generation photocatalysts are composed of multiple components in a suspension (e.g.,WO3/NiWO4,BiOl/ZnTiOa,and C3N4/Ag3VO4).Photocatalysts immobilized on solid substrates are regarded as third generation materials (e.g.,FTO/WO3-ZnO,Steel/TiO2-WO3,and Glass/P-TiO2).Photocatalytic degradation mechanisms,factors affecting the dye degradation,and the lesser-debated uncertainties related to the photocatalysis are also discussed to offer better insights into environmental applications.Furthermore,quantum yields of different photocatalysts are calculated,and a performance evaluation method is proposed to compare photocatalyst systems for dye degradation.Finally,we discuss the present limitations of photocatalytic dye degradation for field applications and the future of the technology.展开更多
Gastric cancer remains the second most frequent cause of cancer-related mortality in the world. Screening programs in some Asian countries are impractical in the majority of other countries worldwide. Therefore, follo...Gastric cancer remains the second most frequent cause of cancer-related mortality in the world. Screening programs in some Asian countries are impractical in the majority of other countries worldwide. Therefore, follow-up of precancerous lesions is advisable for secondary gastric cancer prevention. Intestinal metaplasia (IM) is recognized as a precancerous lesion for gastric cancer, increasing the risk by 6-fold. IM is highly prevalent in the general population, being detected in nearly 1 of every 4 patients undergoing upper endoscopy. The IM prevalence rate is significantly higher in patients with Helicobacter pylori (H. pylori) infection, in first-degree relatives of gastric cancer patients, in smokers and it increases with patient age. IM is the "breaking point" in the gastric carcinogenesis cascade and does not appear to regress following H. pylori eradication, although the cure of infection may slow its progression. Gastric cancer risk is higher in patients with incomplete-type IM, in those with both antral and gastric body involvement, and the risk significantly increases with IM extension over 20% of the gastric mucosa. Scheduled endoscopic control could be cost-effective in IM patients, depending on the yearly incidence of gastric cancer in IM patients, the stage of gastric cancer at diagnosis discovered at surveillance, and the cost of endoscopy. As a pragmatic behavior, yearly endoscopic control would appear justified in all IM patients with at least one of these conditions: (1) IM extension > 20%; (2) the presence of incomplete type IM; (3) first-degree relative of gastric cancer patients; and (4) smokers. In the remaining IM patients, a less intensive (2-3 years) could be proposed.展开更多
Sulfide-containing waste streams are generated by a number of industries. It is emitted into the environment as dis- solved sulfide (S2- and HS-) in wastewaters and as H2S in waste gases. Due to its corrosive nature, ...Sulfide-containing waste streams are generated by a number of industries. It is emitted into the environment as dis- solved sulfide (S2- and HS-) in wastewaters and as H2S in waste gases. Due to its corrosive nature, biological hydrogen sulfide removal processes are being investigated to overcome the chemical and disposal costs associated with existing chemically based removal processes. The nitrogen and sulfur metabolism interacts at various levels of the wastewater treatment process. Hence, the sulfur cycle offers possibilities to integrate nitrogen removal in the treatment process, which needs to be further optimized by appropriate design of the reactor configuration, optimization of performance parameters, retention of biomass and optimization of biomass growth. The present paper reviews the biotechnological advances to remove sulfides from various environments.展开更多
AIM To perform a systematic review and meta-analysis on platelet-to-lymphocyte ratio(PLR) as a risk factor for post-transplant hepatocellular cancer(HCC) recurrence. METHODS A systematic literature search was performe...AIM To perform a systematic review and meta-analysis on platelet-to-lymphocyte ratio(PLR) as a risk factor for post-transplant hepatocellular cancer(HCC) recurrence. METHODS A systematic literature search was performed using PubM ed. Participants of any age and sex, who underwent liver transplantation for HCC were considered following these criteria:(1) studies comparing pre-transplant low vs high PLR values;(2) studies reporting post-transplant recurrence rates; and(3) if more than one study was reported by the same institute, only the most recent was included. The primary outcome measure was set for HCC recurrence after transplantation. RESULTS A total of 5 articles, published between 2014 and 2017, fulfilled the selection criteria. As for the quality of the reported studies, all the investigated articles presented an overall high quality. A total of 899 cases were investigated: 718 cases(80.0%) were males. Three studies coming from European countries and one from Japan presented HCV as the main cause of cirrhosis. On the opposite, one Chinese study presented a greater incidence of HBV-related cirrhotic cases. In all the studies apart one, the PLR cut-off value of 150 was reported. At meta-analysis, high PLR value was associated with a significant increase in recurrence after transplantation(OR = 3.33; 95%CI: 1.78-6.25; P < 0.001). A moderate heterogeneity was observed among the identified studies according to the Higgins I^2 statistic value.CONCLUSION Pre-transplant high PLR values are connected with an increased risk of post-operative recurrence of hepatocellular cancer. More studies are needed for better clarify the biological mechanisms of this results.展开更多
The effect of bainite morphology on mechanical properties of the mixed bainite-martensite microstructure in D6AC low alloy ultra-high strength steel has been studied in the present work. For this purpose, samples aust...The effect of bainite morphology on mechanical properties of the mixed bainite-martensite microstructure in D6AC low alloy ultra-high strength steel has been studied in the present work. For this purpose, samples austenitized at 910℃ for 40 min were quenched in three different ways. Some of the samples were directly oil-quenched, some others were quenched in salt bath at 330 ℃ and the remaining samples were quenched in salt bath at 425 ℃ for various holding times. All samples were tempered at 200 ℃ for 2 h. Microstructures were examined by optical microscopy （OM） and scanning electron microscopy （SEM）. Fracture surfaces also were studied by SEM. Results showed that the mixed microstructure containing martensite and 28 vol.% of the lower bainite exhibited higher yield and tensile strengths than the fully martensitic microstructure. This could be mainly attributed to the partitioning of the prior austenite grains by the lower bainite and enhancing the strength of lower bainite in the mixed microstructure by plastic constraint. Charpy V-notch （CVN） impact energy and ductility were improved by increasing the volume fraction of the lower bainite. This is not the case about the mixed microstructure containing the upper bainite and martensite. As a result, the tensile and CVN impact properties of mixed upper bainite-martensite microstructure are lower than those of the fully martensitic microstructure. Finally, fractography studies showed cleavage fracture at the surface of CVN impact specimens with martensitic and upper bainitic microstructures confirming the tendency to brittle behavior.展开更多
Neural stem cells have great potential for the development of novel therapies for nervous system diseases.However,the proliferation of endogenous neural stem cells following brain ischemia is insufficient for central ...Neural stem cells have great potential for the development of novel therapies for nervous system diseases.However,the proliferation of endogenous neural stem cells following brain ischemia is insufficient for central nervous system self-repair.Ginkgolide B has a robust neuroprotective effect.In this study,we investigated the cell and molecular mechanisms underlying the neuroprotective effect of ginkgolide B on focal cerebral ischemia/reperfusion injury in vitro and in vivo.Neural stem cells were treated with 20,40 and 60 mg/L ginkgolide B in vitro.Immunofluorescence staining was used to assess cellular expression of neuron-specific enolase,glial fibrillary acid protein and suppressor of cytokine signaling 2.After treatment with 40 and 60 mg/L ginkgolide B,cells were large,with long processes.Moreover,the proportions of neuron-specific enolase-,glial fibrillary acid protein-and suppressor of cytokine signaling 2-positive cells increased.A rat model of cerebral ischemia/reperfusion injury was established by middle cerebral artery occlusion.Six hours after ischemia,ginkgolide B（20 mg/kg） was intraperitoneally injected,once a day.Zea Longa＇s method was used to assess neurological function.Immunohistochemistry was performed to evaluate the proportion of nestin-,neuron-specific enolase-and glial fibrillary acid protein-positive cells.Real-time quantitative polymerase chain reaction was used to measure m RNA expression of brain-derived neurotrophic factor and epidermal growth factor.Western blot assay was used to analyze the expression levels of brain-derived neurotrophic factor and suppressor of cytokine signaling 2.Ginkgolide B decreased the neurological deficit score,increased the proportion of nestin-,neuron-specific enolase-and glial fibrillary acid protein-positive cells,increased the m RNA expression of brain-derived neurotrophic factor and epidermal growth factor,and increased the expression levels of brain-derived neurotrophic factor and suppressor of cytokine signaling 2 in the ischemic penumbra.Together展开更多
AIM:To compare genotype of Helicobacter pylori(H.pylori) isolated from saliva,dental plaques,gastric biopsy,and stool of each patient in order to evaluate the mode of transmission of H.pylori infection.METHODS:This cr...AIM:To compare genotype of Helicobacter pylori(H.pylori) isolated from saliva,dental plaques,gastric biopsy,and stool of each patient in order to evaluate the mode of transmission of H.pylori infection.METHODS:This cross-sectional descriptive study was performed on 300 antral gastric biopsy,saliva,dental plaque and stool samples which were obtained from patients undergoing upper gastrointestinal tract endoscopy referred to endoscopy centre of Hajar hospital of Shahrekord,Iran from March 2010 to February 2011.Initially,H.pylori strains were identified by rapid urease test(RUT) and polymerase chain reaction(PCR) were applied to determine the presence of H.pylori(ureC) and for genotyping of voculating cytotoxin gene A(vacA) and cytotoxin associated gene A(cagA) genesin each specimen.Finally the data were analyzed by using statistical formulas such as Chi-square and Fisher's exact tests to find any significant relationship between these genes and patient's diseases.P < 0.05 was considered statistically significant,RESULTS:Of 300 gastric biopsy samples,77.66% were confirmed to be H.pylori positive by PCR assay while this bacterium were detected in 10.72% of saliva,71.67% of stool samples.We were not able to find it in dental plaque specimens.The prevalence of H.pylori was 90.47% among patients with peptic ulcer disease(PUD),80% among patients with gastric cancer,and 74.13% among patients with none ulcer dyspepsia(NUD) by PCR assay.The evaluation of vacA and cagA genes showed 6 differences between gastric biopsy and saliva specimens and 11 differences between gastric and stool specimens.94.42% of H.pylori positive specimens were cagA positive and all samples had amplified band both for vacA s and m regions.There was significant relationship between vacA s1a/m1a and PUD diseases(P = 0.04),s2/m2 genotype and NUD diseases(P = 0.05).No statically significant relationship was found between cagA status with clinical outcomes and vacA genotypes(P = 0.65).The evaluation of vacA and cagA genes showed 6 differences between gastr展开更多
Aim： To evaluate for the first time the frequency of Y chromosome microdeletions and the occurrence of the partial deletions of AZFc region in Moroccan men, and to discuss the clinical significance of AZF deletions. ...Aim： To evaluate for the first time the frequency of Y chromosome microdeletions and the occurrence of the partial deletions of AZFc region in Moroccan men, and to discuss the clinical significance of AZF deletions. Methods： We screened Y chromosome microdeletions and partial deletions of the AZFc region of a consecutive group of infertile men （n = 149） and controls （100 fertile men, 76 normospermic men）. AZFa, AZFb, AZFc and partial deletions of the AZFc region were analyzed by polymerase chain reaction （PCR） according to established protocols. Results： Among the 127 infertile men screened for microdeletion, four subjects were found to have microdeletions： two AZFc deletions and two AZFb＋AZFc deletions. All the deletions were found only in azoospermic subjects （4/48, 8.33%）. The overall AZFc deletion frequency was low （4/127, 3.15%）. AZF microdeletions were not observed in either oligoasthenoteratozoospermia （OATS） or the control. Partial deletions of AZFc （gr/gr） were observed in a total of 7 of the 149 infertile men （4.70%） and 7 partial AZFc deletions （gr/gr） were found in the control group （7/176, 3.98%）. In addition, two b2/b3 deletions were identified in two azoospermic subjects （2/149, 1.34%） but not in the control group. Conclusion： Our results suggest that the frequency of Y chromosome AZF microdeletions is elevated in individuals with severe spermatogenic failure and that gr/gr deletions are not associated with spermatogenic failure.展开更多
The stomach is the most frequently involved site for extranodal lymphomas,accounting for nearly two-thirds of all gastrointestinal cases.It is widely accepted that gastric B-cell,low-grade mucosal-associated lymphoid ...The stomach is the most frequently involved site for extranodal lymphomas,accounting for nearly two-thirds of all gastrointestinal cases.It is widely accepted that gastric B-cell,low-grade mucosal-associated lymphoid tissue(MALT)-lymphoma is caused by Helicobacter pylori(H.pylori)infection.MALT-lymphomas may engender different clinical and endoscopic patterns.Often,diagnosis is confirmed in patients with only vague dyspeptic symptoms and without macroscopic lesions on gastric mucosa.H.pylori eradication leads to lymphoma remission in a large number of patients when treatment occurs at an early stage(Ⅰ-Ⅱ1).Neoplasia confined to the submucosa,localized in the antral region of the stomach,and without API2-MALT1 translocation,shows a high probability of remission following H.pylori eradication.When both bacterial infection and lymphoma recur,further eradication therapy is generally effective.Radiotherapy,chemotherapy and,in selected cases,surgery are the available therapeutic options with a high success rate for those patients who fail to achieve remission,while data on immunotherapy with monoclonal antibodies (rituximab)are still scarce.The 5-year survival rate is higher than 90%,but careful,long-term follow-up is required in these patients since lymphoma recurrence has been reported in some cases.展开更多
Engineered magnetic nanoparticles （MNPs） hold great potential in environmental, biomedical, and clin- ical applications owing to their many unique properties. This contribution provides an overview of iron oxide MNP...Engineered magnetic nanoparticles （MNPs） hold great potential in environmental, biomedical, and clin- ical applications owing to their many unique properties. This contribution provides an overview of iron oxide MNPs used in environmental, biomedical, and clinical fields. The first part discusses the use of MNPs for environmental purposes, such as contaminant removal, remediation, and water treatment, with a focus on the use of zero-valent iron, magnetite （Fe304）, and maghemite （~,-Fe203） nanoparticles, either alone or incorporated onto membrane materials. The second part of this review elaborates on the use of MNPs in the biomedical and clinical fields with particular attention to the application of superparamag- netic iron oxide nanoparticles （SP1ONs）, which have gained research focus recently owing to their many desirable features such as biocompatibility, biodegradability, ease of synthesis and absence of hysteresis. The properties of MNPs and their ability to work at both cellular and molecular levels have allowed their application in vitro and in vivo including drug delivery, hyperthermia treatment, radio-therapeutics, gene delivery, and biotherapeutics. Physiochemical properties such as size, shape, and surface and magnetic properties as well as agglomeration of MNPs and methods to enhance their stability are also discussed.展开更多
文摘GRADE建议通过检查95%可信区间(CI)为决定不精确性的最佳方法。在指南实际运用中,如果CI的上、下限值代表了真实效应,而临床实际情况与之不符时,必须降低证据质量级别(即对效应估计值的把握度)。除外当效应值很大且可信区间提示效应稳健,而总样本量不大且事件数很少的情况,其他应考虑因不精确性而降低证据质量级别。作此决定时,可计算有足够检验效能的单个试验所需的病例数(定义为"最优信息样本量",即optimal information size,OIS)。对连续型变量,我们建议用类似方法,首先考虑可信区间上、下限值,再计算OIS。系统评价(SR)所需方法略有不同。如果95%CI不包括相对危险度(RR)为1,且总事件发生数或病例数超过OIS标准,则精确性良好。如果95%CI包括了明显获益或危害(我们建议以RR值<0.75或>1.25作粗标准),即使达到OIS要求,因不精确性而降低证据质量级别较恰当。
基金New-Century Excellent Talents Supporting Program of the Ministry of Education of China NCET-04-0669Foundation for the Author of National Excellent Doctoral Dissertation of China+2 种基金 FANEDD-200464Young Talents Supporting Program of Hubei Province 301161202National Natural Science Foundation of China No. 20675058
文摘This article is to offer a concise review on the use of cytoreductive surgery （CRS） plus intraperitoneal hyperthermic chemotherapy （IPHC） for the treatment of peritoneal carcinomatosis （PC）. Traditionally, PC was treated with systemic chemotherapy alone with very poor response and a median survival of less than 6 too. With the establishment of several phase Ⅱ studies, a new trend has been developed toward the use of CRS plus IPHC as a standard method for treating selected patients with PC, in whom sufficient cytoreduction could be achieved. In spite of the need for more high quality phase Ⅲ studies, there is now a consensus among many surgical oncology experts throughout the world about the use of this new treatment strategy as standard care for colorectal cancer patients with PC. This review summarizes the current status and possible progress in future.
文摘AIM: To quantitatively summarize and appraise the available evidence of urea breath test(UBT) use to diagnose Helicobacter pylori(H. pylori) infection in patients with dyspepsia and provide pooled diagnostic accuracy measures.METHODS: We searched MEDLINE, EMBASE, Cochrane library and other databases for studies addressing the value of UBT in the diagnosis of H. pylori infection. We included cross-sectional studies that evaluated the diagnostic accuracy of UBT in adult patients with dyspeptic symptoms. Risk of bias was assessed using QUADAS(Quality Assessment of Diagnostic Accuracy Studies)-2 tool. Diagnostic accuracy measures were pooled using the random-effects model. Subgroup analysis was conducted by UBT type(13C vs 14C) and by measurement technique(Infrared spectrometry vs Isotope Ratio Mass Spectrometry).RESULTS: Out of 1380 studies identified, only 23 met the eligibility criteria. Fourteen studies(61%) evaluated 13 C UBT and 9 studies(39%) evaluated 14 C UBT. There was significant variation in the type of reference standard tests used across studies.Pooled sensitivity was 0.96(95%CI: 0.95-0.97) andpooled specificity was 0.93(95%CI: 0.91-0.94). Likelihood ratio for a positive test was 12 and for a negative test was 0.05 with an area under thecurve of 0.985. Meta-analyses were associated with a significant statistical heterogeneity that remained unexplained after subgroup analysis. The included studies had a moderate risk of bias.CONCLUSION: UBT has high diagnostic accuracy for detecting H. pylori infection in patients with dyspepsia. The reliability of diagnostic meta-analytic estimates however is limited by significant heterogeneity.
文摘Nonalcoholic fatty liver disease(NAFLD)is quickly becoming one of the most prominent causes of liver disease worldwide.The increasing incidence of NAFLD is tied to the obesity epidemic and the subsequent metabolic derangements brought along with it.Current efforts to elucidate the mechanism and causes of the disease have answered some questions,but much remains unknown about NAFLD.The aim of this article is to discuss the current knowledge regarding the pathogenesis of the disease,as well as the current and future diagnostic,preventative,and therapeutic options available to clinicians for the management of NAFLD.
文摘Nosocomial infections or healthcare associated infections occur in patients under medical care.These infections occur worldwide both in developed and developing countries.Nosocomial infections accounts for 7% in developed and 10% in developing countries.As these infections occur during hospital stay,they cause prolonged stay,disability,and economic burden.Frequently prevalent infections include central line-associated bloodstream infections,catheter-associated urinary tract infections,surgical site infections and ventilator-associated pneumonia.Nosocomial pathogens include bacteria,viruses and fungal parasites.According to WHO estimates,approximately 15% of all hospitalized patients suffer from these infections.During hospitalization,patient is exposed to pathogens through different sources environment,healthcare staff,and other infected patients.Transmission of these infections should be restricted for prevention.Hospital waste serves as potential source of pathogens and about 20%–25% of hospital waste is termed as hazardous.Nosocomial infections can be controlled by practicing infection control programs,keep check on antimicrobial use and its resistance,adopting antibiotic control policy.Efficient surveillance system can play its part at national and international level.Efforts are required by all stakeholders to prevent and control nosocomial infections.
文摘Discharging dye contaminants into water is a major concern around the world.Among a variety of methods to treat dye-contaminated water,photocatalytic degradation has gained attention as a tool for treating the colored water.Herein,we review the recent advancements in photocatalysis for dye degradation in industrial effluents by categorizing photocatalyst materials into three generations.First generation photocatalysts are composed of single-component materials (e.g.,TiO2,ZnO,and CdS),while second generation photocatalysts are composed of multiple components in a suspension (e.g.,WO3/NiWO4,BiOl/ZnTiOa,and C3N4/Ag3VO4).Photocatalysts immobilized on solid substrates are regarded as third generation materials (e.g.,FTO/WO3-ZnO,Steel/TiO2-WO3,and Glass/P-TiO2).Photocatalytic degradation mechanisms,factors affecting the dye degradation,and the lesser-debated uncertainties related to the photocatalysis are also discussed to offer better insights into environmental applications.Furthermore,quantum yields of different photocatalysts are calculated,and a performance evaluation method is proposed to compare photocatalyst systems for dye degradation.Finally,we discuss the present limitations of photocatalytic dye degradation for field applications and the future of the technology.
文摘Gastric cancer remains the second most frequent cause of cancer-related mortality in the world. Screening programs in some Asian countries are impractical in the majority of other countries worldwide. Therefore, follow-up of precancerous lesions is advisable for secondary gastric cancer prevention. Intestinal metaplasia (IM) is recognized as a precancerous lesion for gastric cancer, increasing the risk by 6-fold. IM is highly prevalent in the general population, being detected in nearly 1 of every 4 patients undergoing upper endoscopy. The IM prevalence rate is significantly higher in patients with Helicobacter pylori (H. pylori) infection, in first-degree relatives of gastric cancer patients, in smokers and it increases with patient age. IM is the "breaking point" in the gastric carcinogenesis cascade and does not appear to regress following H. pylori eradication, although the cure of infection may slow its progression. Gastric cancer risk is higher in patients with incomplete-type IM, in those with both antral and gastric body involvement, and the risk significantly increases with IM extension over 20% of the gastric mucosa. Scheduled endoscopic control could be cost-effective in IM patients, depending on the yearly incidence of gastric cancer in IM patients, the stage of gastric cancer at diagnosis discovered at surveillance, and the cost of endoscopy. As a pragmatic behavior, yearly endoscopic control would appear justified in all IM patients with at least one of these conditions: (1) IM extension > 20%; (2) the presence of incomplete type IM; (3) first-degree relative of gastric cancer patients; and (4) smokers. In the remaining IM patients, a less intensive (2-3 years) could be proposed.
基金Project supported by the National Natural Science Foundation ofChina (No. 30070017)the Science and Technology Foundationfor Key Project of Zhejiang Province (No. 2003C13005), China
文摘Sulfide-containing waste streams are generated by a number of industries. It is emitted into the environment as dis- solved sulfide (S2- and HS-) in wastewaters and as H2S in waste gases. Due to its corrosive nature, biological hydrogen sulfide removal processes are being investigated to overcome the chemical and disposal costs associated with existing chemically based removal processes. The nitrogen and sulfur metabolism interacts at various levels of the wastewater treatment process. Hence, the sulfur cycle offers possibilities to integrate nitrogen removal in the treatment process, which needs to be further optimized by appropriate design of the reactor configuration, optimization of performance parameters, retention of biomass and optimization of biomass growth. The present paper reviews the biotechnological advances to remove sulfides from various environments.
文摘AIM To perform a systematic review and meta-analysis on platelet-to-lymphocyte ratio(PLR) as a risk factor for post-transplant hepatocellular cancer(HCC) recurrence. METHODS A systematic literature search was performed using PubM ed. Participants of any age and sex, who underwent liver transplantation for HCC were considered following these criteria:(1) studies comparing pre-transplant low vs high PLR values;(2) studies reporting post-transplant recurrence rates; and(3) if more than one study was reported by the same institute, only the most recent was included. The primary outcome measure was set for HCC recurrence after transplantation. RESULTS A total of 5 articles, published between 2014 and 2017, fulfilled the selection criteria. As for the quality of the reported studies, all the investigated articles presented an overall high quality. A total of 899 cases were investigated: 718 cases(80.0%) were males. Three studies coming from European countries and one from Japan presented HCV as the main cause of cirrhosis. On the opposite, one Chinese study presented a greater incidence of HBV-related cirrhotic cases. In all the studies apart one, the PLR cut-off value of 150 was reported. At meta-analysis, high PLR value was associated with a significant increase in recurrence after transplantation(OR = 3.33; 95%CI: 1.78-6.25; P < 0.001). A moderate heterogeneity was observed among the identified studies according to the Higgins I^2 statistic value.CONCLUSION Pre-transplant high PLR values are connected with an increased risk of post-operative recurrence of hepatocellular cancer. More studies are needed for better clarify the biological mechanisms of this results.
文摘The effect of bainite morphology on mechanical properties of the mixed bainite-martensite microstructure in D6AC low alloy ultra-high strength steel has been studied in the present work. For this purpose, samples austenitized at 910℃ for 40 min were quenched in three different ways. Some of the samples were directly oil-quenched, some others were quenched in salt bath at 330 ℃ and the remaining samples were quenched in salt bath at 425 ℃ for various holding times. All samples were tempered at 200 ℃ for 2 h. Microstructures were examined by optical microscopy （OM） and scanning electron microscopy （SEM）. Fracture surfaces also were studied by SEM. Results showed that the mixed microstructure containing martensite and 28 vol.% of the lower bainite exhibited higher yield and tensile strengths than the fully martensitic microstructure. This could be mainly attributed to the partitioning of the prior austenite grains by the lower bainite and enhancing the strength of lower bainite in the mixed microstructure by plastic constraint. Charpy V-notch （CVN） impact energy and ductility were improved by increasing the volume fraction of the lower bainite. This is not the case about the mixed microstructure containing the upper bainite and martensite. As a result, the tensile and CVN impact properties of mixed upper bainite-martensite microstructure are lower than those of the fully martensitic microstructure. Finally, fractography studies showed cleavage fracture at the surface of CVN impact specimens with martensitic and upper bainitic microstructures confirming the tendency to brittle behavior.
基金supported by the National Natural Science Foundation of China,No.81073082 to JSZ
文摘Neural stem cells have great potential for the development of novel therapies for nervous system diseases.However,the proliferation of endogenous neural stem cells following brain ischemia is insufficient for central nervous system self-repair.Ginkgolide B has a robust neuroprotective effect.In this study,we investigated the cell and molecular mechanisms underlying the neuroprotective effect of ginkgolide B on focal cerebral ischemia/reperfusion injury in vitro and in vivo.Neural stem cells were treated with 20,40 and 60 mg/L ginkgolide B in vitro.Immunofluorescence staining was used to assess cellular expression of neuron-specific enolase,glial fibrillary acid protein and suppressor of cytokine signaling 2.After treatment with 40 and 60 mg/L ginkgolide B,cells were large,with long processes.Moreover,the proportions of neuron-specific enolase-,glial fibrillary acid protein-and suppressor of cytokine signaling 2-positive cells increased.A rat model of cerebral ischemia/reperfusion injury was established by middle cerebral artery occlusion.Six hours after ischemia,ginkgolide B（20 mg/kg） was intraperitoneally injected,once a day.Zea Longa＇s method was used to assess neurological function.Immunohistochemistry was performed to evaluate the proportion of nestin-,neuron-specific enolase-and glial fibrillary acid protein-positive cells.Real-time quantitative polymerase chain reaction was used to measure m RNA expression of brain-derived neurotrophic factor and epidermal growth factor.Western blot assay was used to analyze the expression levels of brain-derived neurotrophic factor and suppressor of cytokine signaling 2.Ginkgolide B decreased the neurological deficit score,increased the proportion of nestin-,neuron-specific enolase-and glial fibrillary acid protein-positive cells,increased the m RNA expression of brain-derived neurotrophic factor and epidermal growth factor,and increased the expression levels of brain-derived neurotrophic factor and suppressor of cytokine signaling 2 in the ischemic penumbra.Together
基金Supported by The Islamic Azad University,Shahre Kord Branch-Iran grant 89/8761
文摘AIM:To compare genotype of Helicobacter pylori(H.pylori) isolated from saliva,dental plaques,gastric biopsy,and stool of each patient in order to evaluate the mode of transmission of H.pylori infection.METHODS:This cross-sectional descriptive study was performed on 300 antral gastric biopsy,saliva,dental plaque and stool samples which were obtained from patients undergoing upper gastrointestinal tract endoscopy referred to endoscopy centre of Hajar hospital of Shahrekord,Iran from March 2010 to February 2011.Initially,H.pylori strains were identified by rapid urease test(RUT) and polymerase chain reaction(PCR) were applied to determine the presence of H.pylori(ureC) and for genotyping of voculating cytotoxin gene A(vacA) and cytotoxin associated gene A(cagA) genesin each specimen.Finally the data were analyzed by using statistical formulas such as Chi-square and Fisher's exact tests to find any significant relationship between these genes and patient's diseases.P < 0.05 was considered statistically significant,RESULTS:Of 300 gastric biopsy samples,77.66% were confirmed to be H.pylori positive by PCR assay while this bacterium were detected in 10.72% of saliva,71.67% of stool samples.We were not able to find it in dental plaque specimens.The prevalence of H.pylori was 90.47% among patients with peptic ulcer disease(PUD),80% among patients with gastric cancer,and 74.13% among patients with none ulcer dyspepsia(NUD) by PCR assay.The evaluation of vacA and cagA genes showed 6 differences between gastric biopsy and saliva specimens and 11 differences between gastric and stool specimens.94.42% of H.pylori positive specimens were cagA positive and all samples had amplified band both for vacA s and m regions.There was significant relationship between vacA s1a/m1a and PUD diseases(P = 0.04),s2/m2 genotype and NUD diseases(P = 0.05).No statically significant relationship was found between cagA status with clinical outcomes and vacA genotypes(P = 0.65).The evaluation of vacA and cagA genes showed 6 differences between gastr
文摘Aim： To evaluate for the first time the frequency of Y chromosome microdeletions and the occurrence of the partial deletions of AZFc region in Moroccan men, and to discuss the clinical significance of AZF deletions. Methods： We screened Y chromosome microdeletions and partial deletions of the AZFc region of a consecutive group of infertile men （n = 149） and controls （100 fertile men, 76 normospermic men）. AZFa, AZFb, AZFc and partial deletions of the AZFc region were analyzed by polymerase chain reaction （PCR） according to established protocols. Results： Among the 127 infertile men screened for microdeletion, four subjects were found to have microdeletions： two AZFc deletions and two AZFb＋AZFc deletions. All the deletions were found only in azoospermic subjects （4/48, 8.33%）. The overall AZFc deletion frequency was low （4/127, 3.15%）. AZF microdeletions were not observed in either oligoasthenoteratozoospermia （OATS） or the control. Partial deletions of AZFc （gr/gr） were observed in a total of 7 of the 149 infertile men （4.70%） and 7 partial AZFc deletions （gr/gr） were found in the control group （7/176, 3.98%）. In addition, two b2/b3 deletions were identified in two azoospermic subjects （2/149, 1.34%） but not in the control group. Conclusion： Our results suggest that the frequency of Y chromosome AZF microdeletions is elevated in individuals with severe spermatogenic failure and that gr/gr deletions are not associated with spermatogenic failure.
文摘The stomach is the most frequently involved site for extranodal lymphomas,accounting for nearly two-thirds of all gastrointestinal cases.It is widely accepted that gastric B-cell,low-grade mucosal-associated lymphoid tissue(MALT)-lymphoma is caused by Helicobacter pylori(H.pylori)infection.MALT-lymphomas may engender different clinical and endoscopic patterns.Often,diagnosis is confirmed in patients with only vague dyspeptic symptoms and without macroscopic lesions on gastric mucosa.H.pylori eradication leads to lymphoma remission in a large number of patients when treatment occurs at an early stage(Ⅰ-Ⅱ1).Neoplasia confined to the submucosa,localized in the antral region of the stomach,and without API2-MALT1 translocation,shows a high probability of remission following H.pylori eradication.When both bacterial infection and lymphoma recur,further eradication therapy is generally effective.Radiotherapy,chemotherapy and,in selected cases,surgery are the available therapeutic options with a high success rate for those patients who fail to achieve remission,while data on immunotherapy with monoclonal antibodies (rituximab)are still scarce.The 5-year survival rate is higher than 90%,but careful,long-term follow-up is required in these patients since lymphoma recurrence has been reported in some cases.
文摘Engineered magnetic nanoparticles （MNPs） hold great potential in environmental, biomedical, and clin- ical applications owing to their many unique properties. This contribution provides an overview of iron oxide MNPs used in environmental, biomedical, and clinical fields. The first part discusses the use of MNPs for environmental purposes, such as contaminant removal, remediation, and water treatment, with a focus on the use of zero-valent iron, magnetite （Fe304）, and maghemite （~,-Fe203） nanoparticles, either alone or incorporated onto membrane materials. The second part of this review elaborates on the use of MNPs in the biomedical and clinical fields with particular attention to the application of superparamag- netic iron oxide nanoparticles （SP1ONs）, which have gained research focus recently owing to their many desirable features such as biocompatibility, biodegradability, ease of synthesis and absence of hysteresis. The properties of MNPs and their ability to work at both cellular and molecular levels have allowed their application in vitro and in vivo including drug delivery, hyperthermia treatment, radio-therapeutics, gene delivery, and biotherapeutics. Physiochemical properties such as size, shape, and surface and magnetic properties as well as agglomeration of MNPs and methods to enhance their stability are also discussed.
