Isolation and Identification of Pseudomonas solanacearum and Its Drug Sensitivity Test

Ten pathogenic strains were isolated fi-om gingers infected by blast, and were identified by substrate utilization test and biochemical test. The identifica- tion results showed that these ten strains accorded with the basic characteristics of Pseudomonas solanacearum. Drug sensitivity test of ten strains was carried out, and prevention agents were screened to provide an experimental basis for the control of ginger blast.

Drug Sensitivity Test and Regression Verification of Escherichia coli from Rex Rabbit

[ Objectives] The paper aimed to select drugs reasonably for treatment of rex rabbit colibacillosis, and to isolate the pathogenicity of Escherichia coll. [ Methods ] Pathogen isolation, drug sensitivity test and pathogen regression test were performed with rex rabbits killed by E. coli in clinic. [ Results] The isolate was E. coli 0-23, susceptible to amikacin and cefotaxime sodium; when the challenge dose was 1.0 mL/rabbit （about one billion E. coli）, the test animal would discharge mucous feces. [ Conclusions] The results provided model support for clinical medicine selection against rex rabbit colibacillosis.

Isolation, Identification and Drug Sensitivity Test of a Pathogenic Escherichia coli Strain from Minks with Diarrhea

[Objectives] The study aimed to identify the pathogen that causes diarrhea in minks. [Methods] Liver tissues were aseptically collected from dead minks with diarrhea. By bacterial isolation and culture,morphological observation,biochemical test and pathogenicity test,the isolated strain was identified as pathogenic E. coli. [Results]The pathogen causing diarrhea in minks was confirmed as a pathogenic E. coli strain. Drug sensitivity test indicated that the isolated pathogenic E. coli strain was highly sensitive to ceftazidime,cefotaxime,enrofloxacin,florfenicol and cephradine,moderately sensitive to ampicillin,ciprofloxacin,amikacin,doxycycline,lincomycin and gentamycin,and resistant to amoxycillin,neomycin,spectinomycin,polymyxin and penicillin. [Conclusions] This study provided reference for the prevention and control of abortion in female minks in Qinhuangdao region.

Clinical Distribution and Drug Resistance of Acinetobacter baumannii in a Hospital from 2019 to 2021

Objective:To analyze the clinical distribution and drug resistance of Acinetobacter baumannii(AB)and provide reference for the treatment of AB infection.Methods:AB isolated from clinical specimens of Huaihua First People’s Hospital from 2019 to 2021 were collected and identified by VITEK 2 Compact,an automated microbial identification and susceptibility testing system,in which drug sensitivity test was also performed.Excel was used for statistical analysis.Results:Among the 1,311 AB strains,81.16%(1,064 strains)were from sputum samples,and the departments with the highest detections rates of AB were neurosurgery(24.33%),intensive care(15.48%)and infectious disease(11.44%).The drug sensitivity test showed that the resistance rate of 1,311 AB strains to compound sulfamethoxazole and amikacin was 28.38%and 20.54%,respectively,and the resistance rate to 10 other kinds of common antibiotics was more than 40%.Conclusion:The 1,311 AB strains isolated were widely distributed in clinical settings and had strong resistance to commonly used antibiotics.Therefore,it is necessary to strengthen the monitoring of pathogens and drug resistance,formulate reasonable and effective infection control measures,and ensure that antibiotics are used in a reasonable manner.

Pathologic complete response to conversion therapy in hepatocellular carcinoma using patient-derived organoids:A case report

BACKGROUND For primary liver cancer,the key to conversion therapy depends on the effectiveness of drug treatment.Patient-derived tumor organoids have been demonstrated to improve the efficacy of conversion therapy by identifying individualtargeted effective drugs,but their clinical effects in liver cancer remain unknown.CASE SUMMARY We described a patient with hepatocellular carcinoma(HCC)who achieved pathologic complete response(pCR)to conversion therapy guided by the patientderived organoid(PDO)drug sensitivity testing.Despite insufficiency of the remaining liver volume after hepatectomy,the patient obtained tumor reduction after treatment with the PDO-sensitive drugs and successfully underwent radical surgical resection.Postoperatively,pCR was observed.CONCLUSION PDOs contributes to screening sensitive drugs for HCC patients to realize the personalized treatment and improve the conversion therapy efficacy.

Improving treatment plan and mental health in children with abdominal infection for broad-spectrum bacterial infections

BACKGROUND Pediatric abdominal infection is a common but serious disease that requires timely and effective treatment.In surgical treatment,accurate diagnosis and rational application of antibiotics are the keys to improving treatment effects.AIM To investigate the effect of broad-spectrum bacterial detection on postoperative antibiotic therapy.METHODS A total of 100 children with abdominal infection who received surgical treatment in our hospital from September 2020 to July 2021 were grouped.The observation group collected blood samples upon admission and sent them for broad-spectrum bacterial infection nucleic acid testing,and collected pus or exudate during the operation for bacterial culture and drug sensitivity testing;the control group only sent bacterial culture and drug sensitivity testing during the operation.RESULTS White blood cell count,C-reactive protein,procalcitonin,3 days after surgery,showed better postoperative index than the control group(P<0.05).The hospital stay in the observation group was significantly shorter than that in the control group.The hospitalization cost in the observation group was significantly lower than that in the control group,and the difference between the two groups was statistically significant(P<0.05).CONCLUSION Early detection of broad-spectrum bacterial infection nucleic acids in pediatric abdominal infections can help identify pathogens sooner and guide the appropriate use of antibiotics,improving treatment outcomes and reducing medical costs to some extent.

Comparison of Antibacterial Activities of Six Bacillus amyloliquefaciens Strains

In this study, six bacterial strains were isolated from the sediment, probiotic fermentation products, and lake sediments, they were identified as Bacillus amyloliquefaciens using genetic evolution analysis, which were named B3, B4, B5, XD3, YF6, and YF8. The comparison of the antibacterial activity, hemolytic activity, and antibiotic sensitivity of six Bacillus amyloliquefaciens strains laid a foundation for the development and application of antimicrobial peptide products. A surface activity assay was used to determine the production of biosurfactants in six Bacillus amyloliquefaciens strains. With Staphylococcus aureus and Escherichia coli as indicator bacteria, their antibacterial activity was determined using the agar diffusion method;the same diffusion method was used to determine the antibiotic susceptibility of Bacillus amyloliquefaciens. The results showed that the six Bacillus amyloliquefaciens strains had obvious biosurface activity, and the bacteria inhibited Staphylococcus aureus and Escherichia coli, from strong to weak: YF8, XD3, B3, B4, YF6, and B5. Strain YF8 had the best broad-spectrum bacteriostatic effect, followed by strain XD3. All Bacillus amyloliquefaciens strains were susceptible to 16 common drugs, except for Bacillus amyloliquefaciens strain YF8, which was intermediate to neomycin. The study shows that Bacillus amyloliquefaciens and secondary metabolites have the ability to produce a variety of active peptides, exert a certain inhibitory effect on common pathogens, and have the potential to develop as animal probiotics.

Isolation and Identification of Drug-resistant Escherichia coli Strains from Chickens

[Objective] This study aimed to isolate and identify the drug-resistant Es- cherichia coli strains from chickens. [Method] E. coli strains were isolated from the fecal samples collected from five chicken farms around Shangqiu City, and verified by biochemical and pathogenic assay. [Result] Among the 35 isolated E. coli stains, 11 E. coil stains were sensitive to florfenicol, amikacin, neomycin and gentamicin; 12 E. coli stains were moderately sensitive to ciprofloxacin, doxycycline and norfloxacin; 15 E. coil stains were resistant against erythromycin, penicillin and streptomycin. [Conclusion] Strengthening biosecurity measures, rationally using vaccine and choosing effective antibiotics are the most cost-efficient methods to control E. coli.

Isolation,Identification and Drug Tolerance Analysis of Pathogenic Staphylococcus aureus from Broilers

White feather broilers in some broiler farm in Chengde area developed arthritis and died acutely. In order to identify the pathogen inducing the disease and death of the white feather broilers, samples such as livers and joint pus were collected from dead broilers under sterile condition, and one pathogenic strain was isolated. The isolate was identified to be Staphylococcus aureus through isolated culture, morphologic observation, inspection of biochemical property and animal test. The drug sensitivity test showed that the isolate was sensitive to ceftazidime, enrofloxacin, ceftriaxone, lincomycin and amikacin, but resistant to other drugs to different degrees.

Monitoring and Analysis on Multi Drug Resistance of Escherichia coli from Captive Population Amur Tiger

In order to investigate the multi drug resistance to Escherichia coli from captive population Amur tiger,E. coli strains were isolated from the fecal samples of tiger in Heilongjiang Amur Tiger Park in Harbin. The sensitivity of E. coli isolates to 14 antibiotics was determined by scrip diffusion method. The results indicated that all the isolates varied in drug resistance to different antibiotics; the isolates gave high resistance to ampicillin,with a drug fast rate of 100%; over80% of the isolates were resistant to tetracycline and Paediatric Compound Sulfamethoxazole Tablets(SMZ- TMP),and over 70% of the isolates were sensitive to aztreonam,amoxicillin /potassium clavulanate. Most of the isolates had high sensitive to aztreonam and amoxicillin / clavulanate acid.

Screening and Efficacy Observation of Traditional Chinese Medicine Against Chicken Pathogenic Escherichia coli

[ Objective] The aim of this study was to lay a foundation for obtaining effective traditional Chinese medicine preparations controlling chicken colibacillosis. [ Method] With the western medicine Lomeflbxacin Hydrochloride and Sodium Chloride Injection as the control, drug sensitivity tests of 15 single traditional Chinese herbs and seven self-made Chinese herbal compounds were conducted. Subsequently, the single traditional Chinese herbs presenting good in vitro antibacterial effects against Escherichia coli and all the seven compounds were given to the chicks artificially infected with E. coil to observe their efficacies. [ Result] The results of drug sensitivity tests showed that all the 15 traditional Chinese herbs had certain antibacterial effect against E. coli, among which aloe, pomegranate rind and radix sanguisorbae were the best. Compound 1, 2 and 5 had good antibacterial effects in vitro. By in vivo test, traditional Chinese medicines showed superior efficacies on infected chicks than western medicine, and compound 1 and 2 performed well. [ConclusiOn] Traditional Chinese medicine preparations are good at controlling Chicken colibacillosis, but their bacteriostasis mechanism in vivo was different with that in vitro.

Diagnosis and Treatment of Hemorrhagic Pneumonia of Mink

[Objective] The paper was to diagnose and treat hemorrhagic pneumonia of mink. [Method] The diseased minks bred by one raiser in Huangtian Village of Changli County in Qinhuangdao City were used as experimental materials. It was necropsied, and its tissues such as liver, kidney, spleen and lung were taken under aseptic condition, then inoculated into general nutrition agar and blood agar. The bacteria were isolated and purified, and the strains obtained were carried out animal inoculation test and drug sensitivity test. Finally, the relevant treatment and preven- tive measures were put forward. [Conclusion] The bacteria isolated were detected to be negative by Gram staining; it formed hemolysis ring in blood agar; the bacteria could ferment glucose and xylose, which could not ferment sucrose, lactose, maltose and esculin; it was positive in catalase and oxidase test, and negative in urease test and hydrogen sulfide test; so the strain was indentified to be Pseudomonas aerugi- nosa. Drug sensitivity test showed that the bacteria were highly sensitive to ciprofloxacin, which had tolerance to cefoxitin. [Conclusion] The study laid foundation for diagnosis and treatment of hemorrhagic pneumonia of mink.

Establishment of a nested-ASP-PCR method to determine the clarithromycin resistance of Helicobacter pylori

AIM: To investigate clarithromycin resistance positions 2142, 2143 and 2144 of the 23 Sr RNA gene in Helicobacter pylori(H. pylori) by nested-allele specific primer-polymerase chain reaction(nested-ASP-PCR).METHODS: The gastric tissue and saliva samples from 99 patients with positive results of the rapid urease test(RUT) were collected. The nested-ASP-PCR method was carried out with the external primers and inner allele-specific primers corresponding to the reference strain and clinical strains. Thirty gastric tissue and saliva samples were tested to determine the sensitivity of nested-ASP-PCR and ASP-PCR methods. Then, clarithromycin resistance was detected for 99 clinical samples by using different methods, including nestedASP-PCR, bacterial culture and disk diffusion. RESULTS: The nested-ASP-PCR method was successfully established to test the resistance mutation points 2142, 2143 and 2144 of the 23 SrR NA gene of H. pylori. Among 30 samples of gastric tissue and saliva, the H. pylori detection rate of nested-ASP-PCR was 90% and 83.33%, while the detection rate of ASP-PCR was just 63% and 56.67%. Especially in the saliva samples, nested-ASP-PCR showed much higher sensitivity in H. pylori detection and resistance mutation rates thanASP-PCR. In the 99 RUT-positive gastric tissue and saliva samples, the H. pylori-positive detection rate by nested-ASP-PCR was 87(87.88%) and 67(67.68%), in which there were 30 wild-type and 57 mutated strains in gastric tissue and 22 wild-type and 45 mutated strains in saliva. Genotype analysis showed that three-points mixed mutations were quite common, but different resistant strains were present in gastric mucosa and saliva. Compared to the high sensitivity shown by nested-ASP-PCR, the positive detection of bacterial culture with gastric tissue samples was 50 cases, in which only 26 drug-resistant strains were found through analyzing minimum inhibitory zone of clarithromycin. CONCLUSION: The nested-ASP-PCR assay showed higher detection sensitivity than ASP-PCR and drug sensitivity testing, which could be performed to evaluate clarithromycin resistance of H. pylori.

Isolation and Identification of a Pathogenic E.coli Strain Causing Diarrhea in Foxes

[Objectives] The study aimed to identify the pathogenic E. coli strain that caused diarrhea in foxes and to analyze its drug sensitivity.[Methods] A pathogenic E. coli strain was isolated from dead foxes with diarrhea. By conventional bacterial isolation and culture, morphological observation, pathogenicity test and K-B disc method, the isolated strain was identified as pathogenic E. coli .[Results] The isolated pathogen was highly sensitive to ceftriaxone, cefotaxime, ciprofloxacin and lincomycin, moderately sensitive to enrofloxacin, neomycin, gentamycin, spectinomycin, florfenicol, amikacin and polymyxin, and resistant to ampicillin, amoxicillin and doxycycline.[Conclusions] This study provided reference for the prevention and control of diarrheal diseases in foxes in Qinhuangdao region.

Isolation and Characterization of E. Coli O157 : H7 from Infected Newborn Calves in Northeast China

Escherichia coli O157 : H7 is a foodborne pathogen that poses a major threat to public health. Epidemiologic investigations have identified dairy cows, especially calves, are the principal reservoir of E. coli O157 : H7. In this study, based on the results, E. coli O157 : H7 was the main cause of E. coli disease outbreak in late October, 2015, and more than 90% of newborn calves died of serious diarrhea. Through further experiments, the drug sensitivity and resistance of the strain, the expression of the virulence gene and virulence pathogenicity were studied. E. coli O157 : H7 isolates were resistant to 12 antibiotics including penicillin, tetracycline and ampicillin, and were sensitive to eight antibiotics including cefoperazone, ceftazidime and amikacin. Resistance genes included tetB, strB, aadB, aphA, floR, TEM and virulence genes included stx1, eaeA and hlyA. Using specific pathogen free mice, the result showed that the isolate was pathogenic with a median lethal dose of 7.9×107 CFU · mL-1. This study described the pathogenesis and clinical manifestations of E. coli O157 : H7 infection. These results guided the use of antibiotics in prevent and control of bacterial infections in the future.

Diagnosis and Treatment of Swine Streptococcicosis

[ Objective] This paper aimed to sum up the clinical symptoms, pathological changes, diagnosis and control method of swine streptococ- cicosis. [Method] III and dead pigs were dissected and organs such as liver, kidney, spleen and lung were aseptically took to inoculate in sheep blood agar, respectively, with bacteria isolated and purified to Gram staining and microscopy. [ Result] It was positive in Gram staining and hemoly- sis ting was formed on the sheep blood agar; the bacteria could ferment sucrose, sorbital, glucose, mannose, lactose and hydrolyze sodium hippu- rate. [ Conclusion] Through drug sensitive test, it indicated that swine streptococcus suis was highly sensitive to cephalosporin, ciprofloxacin and penicillin, and showed resistance to kanamycin, oxytetracycline, streptomycin and gentamicin.

Isolation and Identification of Aeromonas allosaccharophila from Procambarus clarkii

In order to provide a scientific basis for the control of Aeromonas allosaccharophila from Procambarus clarkii , a dominant strain was isolated from moribund P. clarkii in some farm in Hubei Province, and designated X1. It was preliminarily identified to be A. allosaccharophila through physiological-biochemical test. Further sequence analysis showed that 16S rDNA of this bacterium shared 90% identity with 16S rDNA of A. allosaccharophila , suggesting that it is A. allosaccharophila . Drug sensitivity test showed that isolate X1 was sensitive to doxycycline, cefotaxime, norfloxacin and gentamicin. In animal regression test, the bacterium the same as that from naturally-diseased P. clarkii could be isolated, with the same disease symptoms as well.

Epidemiological study of community- and hospital-acquired intraabdominal infections

Purpose： To investigate and analyze the clinical and etiological characteristics of community-acquired intraabdominal infections （CIAIs） and hospital-acquired or nosocomial intraabdominal infections （NIAIs） in a comprehensive hospital, to understand the characteristics, pathogen composition, and drug resistance of CIAls as well as NIAIs, and to provide a reference for clinical treatment. Methods： We collected the clinical data of patients with intraabdominal infections admitted to our hospital from June 2013 to June 2014. In vitro drug sensitivity tests were conducted to separate pathogens, and the data were analyzed using the WHONET 5.4 software and SPSS 13.0 software. Results： A total of 221 patients were enrolled in the study, including 144 with CIAls （55 mild-moderate and 89 severe） and 77 with NIAIs. We isolated 322 pathogenic strains, including 234 strains of gramnegative bacteria, 82 strains of gram-positive bacteria, and 6 strains of fungi. Based on clinical features, NIAIs and severe ClAls presented significantly higher values in age, length of hospital stay, mortality, and the incidence of severe intra-abdominal infection than mild-moderate CIAIs （p 〈 0.05）. There was no significant difference in the prognosis between NIAIs and severe CIAIs. Primary diseases leading to CIAIs and NIAIs mostly were hepatobiliary diseases and gastrointestinal diseases respectively. Bacteria isolated from various types of IAls mainly were Enterobacteriaceae; mild-moderate CIAIs mostly were mono-infection of gram-negative bacteria; NIAIs mostly were mixed infections of gram-negative and grampositive bacteria; and severe CIAls were from either type of infection. The rate of Extended Spectrum β-Lactamase-producing Escherichia coil and Klebsiella pneurnoniae was much higher in NIAIs than in CIAIs （p 〈 0.05）. The antimicrobial drug sensitivity of gram-negative bacteria isolated from NIAIs was significantly lower than that of CIAIs. Conclusion： CIAIs and NIAIs have their own unique clinical features and epidemiological features of pathogens which should be considered during the initial empiric therapy for the rational use of anti- microbial drugs. Regional IAls pathogenic bacteria have their own features in drug resistance, slightly different from some recommendations of 2010 Infectious Diseases Society of America guidelines.