损伤菌对大肠菌群检测不确定度评价的影响

文章通过对比热损伤与正常大肠菌检测不确定度的大小,探讨损伤菌对大肠菌群检测工作的影响。大肠菌群计数方法参照GB4789.3-2010第二法,正常大肠菌和损伤菌分别采用结晶紫中性红胆盐琼脂(VRBA)、胰蛋白胨大豆琼脂(TSA)进行计数。结果表明:正常大肠菌在TSA平板、VRBA平板上计数结果差异不明显,损伤大肠菌在TSA平板上的菌落数明显高于VRBA平板上的菌落数;对正常大肠菌和热损伤大肠菌进行多次检验的扩展不确定度(P=95%,k=2.145)分别为0.035和0.065。由于损伤菌能在适宜的条件下进行修复生长,这将是对食品安全的一个潜在危险。因此食品中损伤菌的存在对微生物检测提出了新的要求,必须引起检验工作者的足够重视。

食品中损伤性沙门氏菌实验模型的建立

食品中损伤性沙门氏菌实验模型的建立宋农，欧阳川军事医学科学院卫生学环境医学研究（３０００５０）王新为由于食品在加工过程中经常用冷热等方法处理，故食品中有可能存在活的损伤沙门氏菌。为便于损伤沙门氏菌的检验，常用２步增菌法。￣［１］国内虽有人用２步法进行...

“什伍膏”治疗急性无菌性软组织损伤的临床研究

目的:研究分析中药配方颗粒组方“什伍膏”在急性无菌性软组织损伤治疗方面的应用与效果。方法:纳入我院2019年7月-2020年2月期间收治的66例急性无菌性软组织损伤患者为本次研究的主要对象,采用双盲随机法分为研究组(36例)及对照组(30例),其中对照组患者接受云南白药喷雾剂治疗,研究组患者接受“什伍膏”治疗,就两组患者临床治疗情况进行评估分析并比较。结果:治疗后研究组患者患侧肢体疼痛、肢体肿胀程度改善情况均显著优于对照组(P<0.05),临床疗效显著高于对照组(P<0.05)。结论:对急性无菌性软组织损伤患者给予“什伍膏”治疗的临床效果确切,起效迅速且止痛消肿效果显著。

废菌棒粉碎分离机的设计和试验

为实现食用菌废弃菌棒的机械化粉碎和脱袋,设计一种粉碎机构。该机构利用挤压和滑切复合产生撕搓效应的原理进行粉碎和脱袋。在废菌棒的力学性能试验结果的基础上,设计粉碎杆和割袋刀。结合废菌棒粉碎分离机的工作原理,研究菌棒径向受力、轴向输送速度和割袋刀的滑切角。搭建试验台,通过分析粉碎合格率、菌袋脱净率和生产率来检验设计的可行性。试验结果表明,在粉碎杆倾角α固定的情况下,驱动转速是影响粉碎合格率、菌袋脱净率、生产率的重要因素;随着驱动转速的增加,粉碎合格率升高,生产率升高,菌袋脱净率降低。该研究结果可为菌袋分离机的整体设计与优化提供重要依据。

茵陈大孔树脂提取物对CCl_4所致肝损伤的影响

目的建立小鼠肝损伤模型,考察AB-8大孔树脂制备的茵陈提取物对CCl4所致肝损伤的保护作用。方法利用AB-8大孔树脂制备30%醇提取物,作用于0.1%CCl4诱导肝损伤模型,观察不同浓度茵陈提取物对肝损伤小鼠ALT、AST等指标的影响。结果与正常组比较,模型组小鼠血清液ALT、AST含量升高;与模型组比较,给药组中高、中剂量组小鼠血清中ALT、AST含量降低,低剂量组无显著性差异。结论AB-8大孔树脂制备的茵陈提取物对CCl4诱导的肝损伤有保护作用。

受损金黄色葡萄球菌对检测不确定度的影响

为探讨受损金黄色葡萄球菌对定量检验工作的影响,本文采用GB法、AOAC法分别对热损伤与正常金黄色葡萄球菌进行重复检测,采用A类不确定度评定方法计算其不确定度,进而评估受损菌对当前检测方法的影响。损伤菌和正常菌用GB法的扩展不确定度分别是0.052和0.032,AOAC法的扩展不确定度分别是0.047和0.014,两种方法受损菌的扩展不确定度值均大于正常菌的值,实验表明损伤状态下菌体细胞的存在会引起检测不确定度的增加,检测人员对此应引起重视。

紫外线对大肠杆菌的损伤机制研究

目的观察紫外线消毒对水中大肠杆菌(E.coli)的损伤情况及其损伤机制。方法选择E.coli ATCC25922为实验菌,用平板计数法研究不同紫外线照射剂量下E.coli的灭活率及损伤情况,用拉曼光谱和透射电子显微镜分别观察紫外线消毒后该菌的膜通透性和细胞形态的变化。结果紫外线消毒后E.coli细胞膜通透性增加4.87倍,拉曼光谱测量显示损伤状态的该菌存在蛋白质、脂质及糖类的结构变化,透射电镜观察显示损伤状态的E.coli质壁出现一定程度的分离。结论紫外线消毒对E.coli的损伤表现在蛋白质、核酸、糖类等多种生物活性分子的不同程度损伤,而不是某种结构的单一损伤。

不同方法检测氯化消毒损伤大肠杆菌的效果评价

目的 评价滤膜法、多管发酵法以及酶底物法对氯化消毒损伤大肠杆菌的检测效果。方法 以大肠杆菌E.coli K12为指示细菌,并利用氯化消毒技术制备消毒损伤细菌,分别采用修复培养法和GB/T 5750—2006《生活饮用水标准检测方法》推荐的滤膜法、多管发酵法以及酶底物法进行检测。结果 修复培养法和多管发酵法均检出消毒损伤大肠杆菌,而滤膜法均未检出消毒损伤大肠杆菌;对于酶底物法,消毒5 min时样品消毒损伤大肠杆菌的检出率为0%-47.50%,消毒20 min所有样品均未检出消毒损伤大肠杆菌。与修复培养法比较,滤膜法和酶底物法消毒损伤大肠杆菌的检出率均较低,差异均有统计学意义（P〈0.05）。结论 多管发酵法可有效检测氯化消毒损伤大肠杆菌。

生活饮用水中损伤性非苛养菌的耐药性分析

目的研究生活饮用水中损伤性非苛养菌的耐药性。方法采用增菌培养基和选择性培养基对某小区生活饮用水进行损伤菌分离,获得分离株后,利用16S rRNA基因测序法进行种属鉴定;采用Kirby-Bauer纸片扩散法进行细菌的抗菌药物敏感性试验。结果在分离的58株损伤性非苛养菌中,耐药菌占51.72%,包括肠球菌属、肠杆菌属、葡萄球菌属、不动杆菌属、假单胞菌属。其中80%的损伤菌表现出对两种及以上抗菌药物耐药。耐药菌对复方新诺明的耐药最为普遍,耐药率为63.33%;对磺胺甲噁唑的耐药次之,占43.33%。结论测试小区生活饮用水中的损伤性非苛养菌耐药性较为普遍,应加强关注其潜在的人群健康风险。

第三腰椎横突综合征动物实验模型建立及实验研究

目的通过模拟第三腰椎横突周围无菌性炎症的方法,建立第三腰椎横突综合征动物实验模型,于两种不同动物重复用同一造模方法以考察其可靠性。方法将90只SD大鼠随机分为四组;正常组、假手术组、材料实验组及模型组。于造模后4、10、30 d进行组织病理学观察;4、lO、30 d进行全血、前列腺环素、内皮素、5-羟色胺观察;0、l、8、15 d进行机械性压迫痛阈实验;将20只日本大耳白纯种兔随机分为四组;模型组、材料实验组、假手术组及正常组。于造模后4、lO、30 d进行组织病理学观察;4、10、30 d进行全血、前列腺环素、内皮素、5-羟色胺观察;0、1、8、15 d进行机械性压迫痛阈实验。结果本模型可以在第三腰椎横突周围出现明显无菌性炎症、淤血、水肿及后期有瘢痕形成,经组织细菌培养,无细菌感染。模型组炎性递质等指标显著高于材料实验组、假手术组及正常组(P<0.01)。结论本模型可以对第三腰椎横突周围无菌性炎症作出真实反映。

GUT BARRIER FUNCTION DAMAGE FOLLOWING MULTIPLE FIREARM INJURIES IN A PORCINE MODEL

Objective. To study the characteristics and pathogenesis of gut barrier damage following multiple firearm injuries in a porcine model. Methods. Twenty four small pigs were divided into 4 groups: control group (n=6, group C), group H (n=6, gunshot induced tangential fracture of parietal bone), group L (n=6, gunshot induced comminuted fracture of bilateral femora) and group M (n=6, combined group H+L). Gastric intramucosal pH (pHi), plasma endotoxin levels in portal vein, and plasma D lactate levels were measured and blood samples were cultured at different intervals after trauma. The animals were sacrificed at 72 h following trauma and intestinal tissues were harvested for pathological examination and diamine oxidase (DAO) activity measurement. Results. In group M at 72 h, pHi was significantly lower than that of group H and L (P< 0.01), and plasma endotoxin level was significantly higher than that of group H (P< 0.01) and group L (P< 0.05). Simultaneously, in groupM, D lactate level was markedly higher than that of group H (P< 0.01), and incidence of positive blood culture was much higher than that of group H and L (P<0.05). Necrosis and exfoliation were revealed at ileum villus top in all traumagroups, especially in group M, in which ileum DAO activity declined most significantly as well. Conclusion. Multiple trauma is prone to cause gastrointestinal ischemia even without hemorrhagic shock. The damage of gut barrier in multiple trauma appears to be more severe than that in one site trauma, thereby promoting gut derived endotoxemia and bacterial translocation and contributing to the development of endogenous infection.SURGICAL TREATMENT OF MALIGNANTESOPHAGEAL TUMORS IN PUMC HOSPITAL Guo Huiqin,Li Zejian ,Zhang Fan1 ,Zhang Zhiyong,Xu Letian ,Li Weidong2,Wang Xiuqin2and Wu Min2Department of Thoracic Surgery, PUMC Hospital, CAMS &PUMC, Beijing 100730Key words malignant esophageal tumors; early diagnosis; FHIT geneTo study how to prolong the postoperative survival time of the patientswith malignant esophageal tumors. The clinical data of 1098 patients with malignant esophageal tumors from 1961 to 1992 were retrospectively analyzed. The deletion of fragile histamine triplet (FHIT) gene (a tumor suppressor gene) in 30 fresh esophageal samples obtained in 1996 was detected with PCR and RT PCR method. The resectability was raised gradually and the operative morbidity and mortality decreased year by year, but there was no significant improvement on the postoperative 5 year survival rate. Delayed diagnosis and irradical resection influenced the long term survival. The deletion of cDNA of FHIT gene was 64.2%in esophageal cancer and 20%in the resected margin of the cancer. We believe that high grade atypical hyperplasia in esophageal epithelium and deletion of FHIT gene in esophageal cancer and its resected margin are pathological and molecular markers for early diagnosis of esophageal cancer respectively, and the latter may be one of the molecular markers for the resection. Early diagnosis and treatment, radical resection, and postoperative nutritional support are very important for the improvement of the postoperative survival time of the patients.

Protective effect of selenium-enriched lactobacilluson CCI_4-induced liver injury in mice and its possible mechanisms

AIM： To study the protective effects and mechanisms of Se-enriched lactobacillus on liver injury caused by carbon tetrachloride （CCl4） in mice. METHODS： Seventy-two ICR mice were randomly divided into four groups： normal group, CCl4-induced model group, low Se-enriched lactobacillus treatment group （L-Se group）, and high Se-enriched lactobacillus treatment group （H-Se group）. During a 3-wk experimental period, the common complete diet was orally provided daily for normal group and model group, and the mice in L-Se and H-Se groups were given a diet with 2 and 4 mg of organoselenium from Se-enriched lactobacillus per kg feed, respectively. From the 2nd wk of experiment, the model group, L-Se group, and H-Se group received abdominal cavity injection of olive oil solution containing 500 mL/L CCl4 （0.07 mL/100 g body mass） to induce liver injury, and the normal group was given olive oil on every other day for over 2 wk. In the first 2 wk post injection with CCl4, mice in each group were killed. The specimens of blood, liver tissue, and macrophages in abdominal cavity fluid were taken. Then the activities of the following liver tissue injury-associated enzymes including glutathione peroxidase （GSH-Px）, superoxide dismutase （SOD）, alanine aminotransferase （ALT） and aspartate aminotransferase （AST） as well as malondialdehyde （MDA） content were assayed. Changes of phagocytic rate and phagocytic index in macrophages were observed with Wright-Giemsa stain. Plasma TNF-α level was measured by radioimmunoassay. The level of intracellular free Ca^2＋ （[Ca^2＋]i） in hepatocytes was detected under a laser scanning confocal microscope. RESULTS： During the entire experimental period, the AST and ALT activities in liver were greatly enhanced by CCl4 and completely blunted by both low and high doses of Se-enriched lactobacillus. The Se-enriched lactobacillus- protected liver homogenate GSH-Px and SOD activities were higher or significantly higher than those in model group and were close to those in normal group. CCl4 significantly increased MDA content in liver homogenates, while administration of Se-enriched lactobacillus prevented MDA elevation. Phagocytic rate and phagocytic index of macrophages decreased after CCl4 treatment compared to those in normal control, but they were dramatically rescued by Se-enriched lactobacillus, showing a greatly higher phagocytic function compared to model group. CCl4 could significantly elevate plasma TNF-α and hepatocyte [Ca^2＋]i level, which were also obviously prevented by Se-enriched lactobacillus. CONCLUSION： Se-enriched lactobacillus can intervene in CCl4-induced liver injury in mice by enhancing macrophage function activity to keep normal and beneficial effects, elevating antioxidant-enzyme activities and reducing lipid peroxidation reaction, inhibiting excessive release of TNF-α, preventing the dramatic elevation of [Ca^2＋]i in hepatocytes.

Direct hemoperfusion with a polymyxin B-immobilized cartridge in intestinal warm ischemia reperfusion

AIM： To investigate the effectiveness of direct hemoperfusion with polymyxin B-immobilized fibers （DHPPMX therapy） on warm ischemia-reperfusion （I/R） injury of the small intestine.METHODS： The proximal jejunum and distal ileum of mongrel dogs were resected. Warm ischemia was performed by clamping the superior mesenteric artery （SMA） and vein （SMV） for 2 h. Blood flow to the proximal small intestine was restored 1 h after reperfusion, and the distal small intestine was used as a stoma. The experiment was discontinued 6 h after reperfusion. The dogs were divided into two groups： the DHP-PMX group （n = 6, DHP-PMX was performed for 180 min; from 10 min prior to reperfusion to 170 rain after reperfusion） and the control group （n = 5）. The rate pressure product （RPP）, SMA blood flow, mucosal tissue blood flow, and intramucosal pH （pHi） were compared between the two groups. The serum interleukin （IL）-10 levels measured 170 min after reperfusion were also compared.RESULTS： The RPP at 6 h after reperfusion was significantly higher in the PMX group than in the control group （12174 ± 1832 mmHg/min vs 8929 ± 1797 mmHg/min, P 〈 0.05）. The recovery rates of the SMA blood flow at I and 6 h after reperfusion were significantly better in the PMX group than in the control group （61%±7% vs 44% ±4%, P 〈 0.05, and 59%±5% vs 35%±5%, P 〈 0.05, respectively）. The recovery rate of the mucosal tissue blood flow and the pHi levels at 6 h after reperfusion were significantly higher in the PMX group （61%±8% vs 31%±3%, P 〈 0.05 and 7.91±0.06 vs 7.69±0.08, P 〈 0.05, respectively）. In addition, the serum IL-IO levels just before DHP-PMX removal were significantly higher in the PMX group than in the control group （1 569 ± 253 pg/mL vs 211± 40 pg/mL, P 〈 0.05）.CONCLUSION： DHP-PMX therapy reduced warm I/R injury of the small intestine. IL-10 may play a role in inhibiting I/R injury during DHP-PMX therapy.

Dynamic expression of pepsinogen C in gastric cancer, precancerous lesions and Helicobacter pylori associated gastric diseases

AIM:To investigate the relationship between the expression of pepsinogen C (PGC) and gastric cancer, precancerous diseases, and Helicobacter pylori (H pylori) infection. METHODS: The expression of PGC was determined by immunohistochemistry method in 430 cases of gastric mucosa. H3 Pylori infection was determined by HE staining, PCR and ELISA in 318 specimens. RESULTS: The positive rate of PGC expression in 54 cases of normal gastric mucosa was 100%. The positive rates of PGC expression in superficial gastritis or gastric ulcer or erosion, atrophic gastritis or gastric dysplasia and gastric cancer decreased significantly in sequence (P<0.05; 100%/89.2% vs 14.3%/15.2% vs 2.4%). The over-expression rate of PGC in group of superficial gastritis with H pyloriinfection was higher than that in group without H pylori infection (P<0.05; x2= 0.032 28/33 vs 15/25). The positive rate of PGC expression in group of atrophic gastritis with H pylori infection was lower than that in group without H pylori infection (P<0.01; x2 = 0.003 4/61 vs9/30), and in dysplasia and gastric cancer. CONCLUSION: The level of PGC expression has a close relationship with the degree of malignancy of gastric mucosa and development of gastric lesions. There is a relationship between H pylori infection and expression of antigen PGC in gastric mucosa, the positive rate of PGC expression increases in early stage of gastric lesions with H pylori infection such as gastric inflammation and decreases during the late stage such as precancerous diseases and gastric cancer. PGC-negative cases with H py/ori-positive gastric lesions should be given special attention.

Intestinal microflora in rats with ischemia/reperfusion liver injury

Objectives: To investigate the intestinal microflora status related to ischemia/reperfusion (I/R) liver injury and explore the possible mechanism. Methods: Specific pathogen free grade Sprague-Dawley rats were randomized into three groups: Control group (n=8), sham group (n=6) and I/R group (n=10). Rats in the control group did not receive any treatment, rats in the I/R group were subjected to 20 min of liver ischemia, and rats in the sham group were only subjected to sham operation. Twenty-two hours later, the rats were sacrificed and liver enzymes and malondialdehyde (MDA), superoxide dismutase (SOD), serum endotoxin,intestinal bacterial counts, intestinal mucosal histology, bacterial translocation to mesenteric lymph nodes, liver, spleen, and kidney were studied. Results: Ischemia/reperfusion increased liver enzymes, MDA, decreased SOD, and was associated with plasma endotoxin elevation in the I/R group campared to those in the sham group. Intestinal Bifidobacteria and Lactobacilli decreased and intestinal Enterobacterium and Enterococcus, bacterial translocation to kidney increased in the I/R group compared to the sham group. Intestinal microvilli were lost, disrupted and the interspace between cells became wider in the I/R group.Conclusion: I/R liver injury may lead to disturbance of intestinal microflora and impairment of intestinal mucosal barrier function,which contributes to endotoxemia and bacterial translocation to kidney.

In vitro and in vivo protective effects of proteoglycan isolated from mycelia of Ganoderma lucidum on carbon tetrachlorideinduced liver injury

AIM： To investigate the possible mechanism of the protective effects of a bioactive fraction, Ganoderma lucidum proteoglycan （GLPG）isolated from Ganoderma luddum mycelia, against carbon tetrachloride-induced liver injury. METHODS： A liver injury model was induced by carbon tetrachloride. Cytotoxicity was measured by MTY assay. The activities of alanine aminotransferase （ALT） and aspartate aminotransferase （AST） were determined with an automatic multifunction-biochemical analyzer and the levels of superoxide dismutase （SOD） and TNF-α were determined following the instructions of SOD kit and TNF radioimmunoassay kit. Uver sections were stained with hematoxylin and eosin （H＆E） for histological evaluation and examined under light microscope. RESULTS： We found that GLPG can alleviate the L-02 liver cells injury induced by carbon tetrachloride （CCh） through the measurements of ALT and AST activities and the administration of GLPG to L-02 cells did not display any toxicity. Furthermore, histological analysis of mice liver injury induced by CCh with or without GLPG pretreatment indicated that GLPG can significantly suppress the toxicity induced by CCh in mice liver. We also found that GLPG reduced TNF-α level induced by CCh in the plasma of mice, whereas increased SOD activity in the rat serum. CONCLUSION： GLPG has hepatic protective activity against CCl4 induced injury both in vitro and in vivo. The possible antihepatotoxic mechanisms may be related to the suppression of TNF-α level and the free radical scavenging activity.

Inactivation of digestive proteases: Another aspect of gut bacteria that should be taken into more consideration

TO THE EDITOR Protein has been one of the main components of our diet, and a large amount of digestive proteases is released into the gut for their digestion. However, these proteases can digest not only the proteins we eat, but also the structural proteins built in our body. To protect against this damage, our body has taken a variety of measures. For instance, these digestive proteases are stored and secreted in the form of zymogen and only activated in gut lumen. These luminal digestive proteases are further prevented from direct contact with epithelial cells by the mucus layer that is incessantly secreted by the goblet cells in gut mucosa. In addition, large quantities of protease inhibitors are produced in the body to inactivate the digestive proteases that have entered the body. Despite these measures, the protection seems still weak and can be easily compromised. For instance,

中性粒细胞外诱捕网在慢性阻塞性肺部疾病免疫发病机制中的研究进展

慢性阻塞性肺疾病(COPD)是一种在全球范围内呈高发趋势的肺部慢性炎症性疾病。随着研究的深入,人们逐渐认识到COPD亦具有自身免疫性疾病的特征,但目前对于COPD中获得性免疫的启动机制仍不明确。气道的慢性中性粒细胞炎症是COPD的一个显著特征。研究发现,中性粒细胞在感染状态下可形成一种主要由DNA构成的网状物质——中性粒细胞外诱捕网(NETs),它除了发挥直接的抗感染效应之外,大量的NETs形成还可造成组织损伤,在一些自身免疫性疾病中,NETs甚至能启动获得性免疫应答。文章综述近年来NETs在COPD免疫发病机制中的研究进展及其作为COPD抗炎靶点的可能性,为今后COPD的抗炎治疗提供新的思路。

Non-steroidal anti-inflammatory drugs-induced small intestinal injury and probiotic agents

Intestinal bacteria play a role in the development of non-steroidal anti-inflammatory drugs （NSAID）-induced small intestinal injury. Agents such as probiotics, able to modi~ the gut ecology, might theoretically be useful in preventing small intestinal damage induced by NSAIDs. The clinical studies available so far do suggest that some probiotic agents can be effective in this respect.

Early enteral nutrition supplemented with probiotics improved the clinical outcomesin patients with severe head injury： protocol for a meta-analysis of randomizedcontrolled trials

Objective： The aim of this systematic review of randomized controlled trials （RCTs） is to determine the effects of earlyenteral nutrition supplemented with probiotics on clinical outcomes in patients with SHI.Methods and analysis： A systematic search will be carried out in PubMed, Cochrane Central Register of ControlledTrials （CENTRAL）, China National Knowledge Infrastructure （CNKI）, WanFang database, and Chinese BiomedicalLiterature （CBM） in order to identify the randomized controlled trials （RCTs） investigated the potential of early enteralnutrition supplemented with probiotics on patients with severe head injury, as well as we will also manually check thebibliographies of eligible studies and topic-related reviews. We will assign two investigators to independently search allpotential citations, extracted data, and appraised risk of bias accordingly, and then STATA software version 12.0 will beused to statistically analyze all data.Ethics and dissemination： The ethics approval and patient written informed consent will not be required because allanalyses in the present study will be performed based on data from published studies. We will submit our systematicreview to a peer-reviewed scientific journal for publication.