Objective To explore the bacterial translocation of mesenteric lymph nodes （MLNs） of the ileum and the spectrum of bacteria in patients with small bowel obstruction.Methods Total 84 patients were divided into study group （with small bowel obstruction） and control group （without small bowel obstruction）. MLNs were obtained under sterile conditions intraoperatively， and which were processed for culture of aerobic and anaerobic organisms. The rate of bacterial translocation and postoperative infection were compared between two groups and the species of bacterial translocation was identified. Results The bacterial translocation rate in the study group was higher than that in the control group 〔57.1% （24/42） versus 16.7% （7/42），χ2=14.775， P＜0.01〕. Escherichia coil was the most commonly bacteria （20）. Emergency surgery and age over 70 years were associated with bacterial translocation （P＜0.05）. Postoperative infection complications rate in the bacterial translocation patients was higher than that in the patients without bacterial translocation 〔29.0% （9/31） versus 3.8% （2/53），χ2=10.965，P＜0.05〕. Conclusions Bacterial translocation to MLNs occurres more frequently in patients with small bowel obstruction，non-elective surgery， and elderly.
Objective To evaluate the effect of hepatocyte growth factor(HGF) on intestinal permeability and bacterial translocation after small bowel transplantation in rats. Methods Twenty Wistar rats were as recptors and twenty SD rats as donors. After heterotopic intestinal grafting, cyclosporine A was administered at 6mg/kg·day intramuscularly for inhibiting rejection. The SD rats were divided into 2 groups(n=10). HGF was administered at 150 μg/kg·day (HGF group) and normal saline was administered at 150 μg/kg·day (controlgroup). Intestinal permeability and bacterial translocation to the mesenteric lymph nodes and portal vein were assessed at the 8th postoperative day. Results The lactulose and lactulose/ mannitol of control group (0.0931%±0.008 5% and 0.132± 0.021) were higher than those of normal reference value (0.015 0%±0.002 0% and 0.020±0.005)（Plt;0.05）. The lactulose and lactulose/ mannitol of HGF group (0.039 6%±0.009 0% and 0.056±0.013) were also higher than those of normal reference value（Plt;0.05）.The bacterial culture positive proportion of lymphaden in HGF group and control group were 10% and 60%, showing statistically significant difference（Plt;0.05）. The bacterial culture positive proportion of portal vein in HGF group and control group were 10% and 20% respectively（P＞0.05）. Conclusion HGF can decrease intestinal permeability and bacterial translocation from the lumen of the graft to the mesenteric lymph nodes,thus improve gut barrier function, may be of help to reduce the incidence of septic complications after intestinal grafting.
In order to inquire into the relation between bacterial L-forms and chronic appendictis,appendices removed from 10 patients with appendicitis were cultured with improved kagans’s solid medium and nutrient medium containing blood respectively.Bacterial forms with bacterial L-form transforms to L-forms and 1 strain of bacillus aerogen with its L-form.The result shows that bacterial form transforms to L-form,then to bacterial form may be related with appendicitis attack,alleviation and attack again.
In order to investigate the mechanism of enterogenous infection, sixty SD rats were randomly allocated into four groups∶ group of intestinal obstruction; group of cyclophosphamide+intestinal obstruction; group of cyclophosphamide and group of sham-operation. Each group included 15 rats. Twenty four hours after obstruction of the terminal ileum, the bacteria in blood of portal vein, blood of heart, peritoneal fluid, mesenteric lymph node (MLN) and content of gut were determined quantitatively, the concentration of endotoxin in portal system were measured. The results showed that early (24 hours) intestinal obstruction led to endotoxemia in portal vein, overgrowth of enteric G－bacili and bacterial translocation into the MLN. The immunosuppressive agent cyclophosphamide not only increased the rate of bacterial translocation into MLN and the number of living bacteria in MLN, but also promoted bacteria to spread into the systemic circulation. The authors conclude that under immunosuppression the bacterial translocation from gut by way of lymphatic channel plays an important role in enterogenous infection.
ObjectiveThe changes of intestinal permeability and relationship of intestinal mucosa and bacterial translocation were studied in rat acute necrotizing pancreatitis (ANP) models.MethodsThe ANP models were made by injection of 5% sodium taurocholate 1.0 ml into pancreatic subcapsula.Then wistar rats were divided into four groups,control group (n=20),ANP group(n=22),treatment model group fed with lactose (n=22) and treatment model group fed with MgSO4 and antibiotic (n=22).After 72 hours,the experimental models were sacrificed.Tissues of pancreas,mesenteric lymph node, ascites were collected for microbiological study.The intestinal permeability was observed by lanthanum tracer.The blood samples were obtained from portal vein and ascites in order to assay the amount of amylase in serum.The pathologic lesions were found in the intestinal villus of the model group, including acute necrosis of intestinal mucosa,necrotichaemorrhage as well as enteroparalysis and a mass of haemorrhagic ascites.ResultsBacterial translocation of model group were markedly elevated than that of control (P＜0.05).There were statistically significant differences in bacterial translocation among three model groups （P＜0.05）.The pathologic lesions were found in the intestinal villus of the model group,including acute necrosis of intestinal mucosa,necrotichaemorrhage as well as enteroparalysis and a mass of haemorrhagic ascites.The lanthanum grain in clearance of intestinal cell of model group can be observed by eletron microscope.ConclusionThere is a severe gut barrier damage and injury in the intestinal mucosa,which lead to bacterial translocation from intestine as the source of pancreatic infection.Cleaning out enteric bacteria,improving intestinal movement and feeding with lactose could decrease bacterial translocation to treat and prevent acute necrotizing pancreatitis.
Objective To investigate the effect of aureolysin （Aur） on staphylococcus aureus biofilm formation of dacron biomaterial surfaces under different Aur concentration. Methods Ninety dacron biomaterials were divided into 3 groups （group A, group IA, control group） with random number table （30 piece in each group）. Dacron biomaterials were put into vials contained staphylococcus aureus （105 CFU/ml） respectively; then Aur was added to make the concentration at 400ng/ml in group A, and group B at 80ng/ml. The thickness and number of staphylococcus aureus biofilm on the surfaces of dacron biomaterials of each group were evaluated by confocal laser microscopy and scanning electron microscopy after incubating 6h, 16h, 24h, 30h, and 48h. Results The thickness and number of staphylococcus aureus biofilm on dacron biomaterials surfaces increased significantly with time dependence in control group. The thickness and number of staphylococcus aureus biofilm in group A were less than those in group B and control group at each time points （P〈0. 05）. The thickness and number in group B were significantly decreased than those in control group （P 〈 0. 05）. Conclusion The study shows that Aur can effectively inhibit the formation of staphylococcus aureus biofilm on dacron biomaterials surfaces with dose dependence.
ObjectiveTo investigate the condensate pollution in the pipeline of severe pneumonia patients undergoing mechanical ventilation.MethodsFrom January 2017 to January 2019, 120 patients with severe pneumonia treated by mechanical ventilation in our hospital were collected continuously. The lower respiratory tract secretions were collected for bacteriological examination. At the same time, the condensed water in the ventilator exhaust pipe was collected for bacteriological examination at 4, 8, 12, 16, 20 and 24 hours after tracheal intubation and mechanical ventilation. The bacterial contamination in the condensed water at different time points was analyzed and separated from the lower respiratory tract. The consistency of bacteria in secretion and drug resistance analysis of bacterial contamination in condensate water were carried out.ResultsOf the 120 patients with severe pneumonia after mechanical ventilation, isolates were cultured in the lower respiratory tract secretions of 102 patients. One strain was cultured in 88 cases, two strains were cultured in 10 cases, and three strains were cultured in 4 cases. The isolates were mainly Gram-negative bacteria (57.5%) and Gram-positive bacteria (42.5%). The most common isolates were Pseudomonas aeruginosa, Staphylococcus aureus and Acinetobacter baumannii. The contamination rate of condensate water was 5.0% at 4 hours, 37.5% at 8 hours, 60.0% at 12 hours, 76.7% at 16 hours, 95.0% at 20 hours, and 100.0% at 24 hours, respectively. The bacterial contamination rate in condensate water at different time points was statistically significant (P=0.000). The pollution rate at 4 hours was significantly lower than that at 8 hours (P=0.000). Gram-negative bacteria accounted for 57.5% and Gram-positive bacteria accounted for 42.5%. The most common isolates were Staphylococcus aureus, Pseudomonas aeruginosa and Acinetobacter baumannii. The consistency of bacteria in lower respiratory tract and condensate water was 83.3% in severe pneumonia patients undergoing mechanical ventilation. The overall resistance of Pseudomonas aeruginosa, Acinetobacter baumannii and Staphylococcus aureus was higher, but the resistance to imipenem/cilastatin was lower.ConclusionsThe bacterial contamination in the condensate of patients with severe pneumonia during mechanical ventilation is serious. The pollution rate is low within 4 hours. It is consistent with the bacterial contamination in lower respiratory tract and the bacterial resistance is high.
ObjectiveTo explore the clinical characters and histopathologic differences between patients with culture-positive and culture-negative prosthetic joint infection (PJI). MethodsBetween January 2012 and July 2013, 66 PJI patients in accord with diagnostic criteria were enrolled. According to the results of preoperative aspiration and intraoperative cultures, the patients were divided into culture-negative group (CN group, n=21) and culture-positive group (CP group, n=45). There was no significant difference in gender, age, height, weight, and body mass index between 2 groups (P>0.05). Preoperative C reactive protein (CRP), erythrocyte sedimentation rate (ESR), and prosthesis survival time were compared between 2 groups. Intraoperative frozen sections and paraffin sections were both performed to identify infections, and histological typing was performed according to Morawietz's methods. ResultsThe preoperative CRP was (1.29±1.84) mg/ dL in CN group and (5.08±9.57) mg/dL in CP group, showing significant difference (t=2.094, P=0.038). The preoperative ESR was (22.86±28.42) mm/1 h in CN group and (36.74±31.26) mm/1 h in CP group, showing significant difference (t=7.761, P=0.000). The median survival time of prosthesis was 72 months (range, 8-504 months) in CN group and 25 months (range, 15 days-300 months) in CP group, showing significant difference (U=2.231, P=0.026). Morawietz's histological typing results showed that 2 cases were rated as type I, 7 cases as type II, and 12 cases as type III in CN group; 6 cases were rated as type I, 25 cases as type II, 13 cases as type III, and 1 case as type IV in CP group. The positive culture rate was 68.18% (45/66), and pathogenic bacteria was dominated by Staphylococcus, accounting for 68.89%. ConclusionThe patients with culture-negative PJI have slow onset and mild inflammatory response, so comprehensive diagnosis should be made based on pathological detection, laboratory examination, and intraoperative cultures.
ObjectiveTo investigate the antibacterial pretreatment protocol for primary fibroblast cell culture from transbronchial biopsies in patients with benign tracheal stenosis (BTS). MethodsFifteen specimens of intratracheal hyperplastic granulation tissue were obtained from 14 BTS patients by transbronchial biopsies. The tissues were divided into 3 groups according to different antibacterial pretreatment with 5 specimens in each group. An usual concentration of antibiotics pretreatment group (group 1) was pretreated by washing with PBS contained 1%-2% penicillin/streptomycin. A high concentration of antibiotics pretreatment group (group 2) was pretreated by washing with PBS contained 6% penicillin/streptomycin. An alchohol and high concentration of antibiotics pretreatment group (group 3) was pretreated by washing with 75% alcohol 3-4 seconds firstly,then by washing with 6% penicillin/streptomycin. After different pretreatment,all tissues were cultured with tissue culture method in the same condition. ResultsThe primary fibroblasts were successfully cultured from the tissue pretreated by method 2 and 3,but not cultured from the tissue pretreated by method 1 with large amount of bacteria. There were significant differences in the furthest radius of cell proliferation between different culture time points in three groups (P<0.01). The differences in the furthest radius of cell proliferation between three groups were not different at 24,48 or 72 h (P>0.05),but were significant between three groups at 96 h (P<0.05). ConclusionAn pretreatment protocol with high concentration of antibiotics or 75% alcohol is feasible in human primary fibroblasts culture from small specimens obtained by transbronchial biopsy.
Objective To discuss the cause and prevention of bacterial translocation after small bowel transplantation (SBT). MethodsMost of the existing literatures concerning bacterial translocation and SBT were reviewed. ResultsThe ischemia/reperfusion injury, graft rejection, graft versus host disease (GVHD) and administration of immunosuppressive drugs were associated with the gut barrier damage, intestinal mobility and transmit dysfunction and luminal potentially pathogenic bacterial overgrowth after SBT which caused the germs and toxin to translocate into recipient tissues, and posed a major threat on the development of sepsis. Conclusion The rate of bacterial translocation after SBT is higher than that of other types of solid organ transplantation,which is the main cause of recipient sepsis affecting the outcome of SBT. Improving the surgical techniques, shortening ischemia preservation time, selective bowel decontamination and improving the methods of nutritional support and immunosuppression would decrease the incidence of bacterial translocation and sepsis, and improve the outcome of SBT.