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.

Multi Drug Resistance Bacterial Isolates of Surgical Site Infection

Multi drug resistance microorganism is considered to be one of the major health problems. The aim of this study was to determine antibiotic susceptibility pattern of bacterial pathogens of surgical site infection. A total 250 samples were included, out of which 62.4% showed significant bacterial growth. Gram negative bacteria were 85.25% and gram positive bacteria were 14.75%;among them 65.38% of the total isolates were multi drug resistance (MDR). The age group between 31 - 40 found the highest number of isolates 22.4%. Among gram negative bacilli, the highest production of MDR was found in Acinetobacter spp. followed by Pseudomonas aeruginosa, Klebsiella pneumoniae and Escherichia coli. In gram positive cocci, the highest production of MDR was found in Staphylococcus aureus. Acinetobacter spp. was found highly susceptible to amikacin and gentamycin 20.1% followed by ofloxacin and ciprofloxacin 18.6% and 16.2% respectively. Staphylococcus aureus showed 100% sensitive to clindamycin whereas penicillin showed 100% resistance followed by amoxycillin (93.75%). Amikacine and clindamycin were drugs of choice for gram negative and gram positive bacteria respectively. This study showed that alarming increase of infections was caused by multi drug resistance bacterial organisms. It increases length of stay and may produce lasting sequelae and requires extra resources for investigations, management and nursing care. Surveillance of surgical site infection is a useful tool to demonstrate the magnitude of the problem and find out appropriate preventive methods.

A Case Study of Multi Drug-Resistant Tuberculosis (MDR-TB), HIV and Diabetes Mellitus (Dm) Comorbidity: Triple Pathology;Challenges and Prospects

Tuberculosis (TB), diabetes mellitus and HIV co-morbidity is a rare and interrelated health condition with associated high morbidity and mortality especially in developing countries with high prevalence of TB. It has become an emerging concern to epidemiologists and TB control programs due to complexities in its control and management. Managing MDR-TB, DM and HIV comorbidity is challenging, with risk of unfavorable outcome;consequently, close monitoring is necessary. Individuals with weak immunity resulting from diseases such as uncontrolled Diabetes Mellitus (DM) and HIV have a higher risk of developing TB or progression from latent to active TB. We present a 65-year old known diabetic patient who presented to Royal Cross Hospital Ugwueke Abia State, Nigeria with a one-year history of recurrent productive cough with associated night sweats, low grade fever and marked weight loss. A diagnosis of drug-resistant TB with DM/HIV co-morbidity was made and co-managed by experts from the respective clinics and the State TB control program. The patient was declared cured (7 months consecutive negative cultures each taken 30 days apart) after completing 20 months of conventional MDR-TB treatment. The patient showed remarkable clinical improvement including weight gain, good diabetic control and significant increase in CD4 (700 cells). Managing MDR-TB patients with diabetes and HIV is challenging, however, appropriate treatment, psychosocial support, adequate blood sugar control as well as monthly monitoring of patients with requisite investigations are vital in achieving good treatment outcome.

Incidence, risk factors and clinical outcome of multidrug-resistant organisms after heart transplantation

BACKGROUND Transplant recipients commonly harbor multidrug-resistant organisms(MDROs),as a result of frequent hospital admissions and increased exposure to antimi-crobials and invasive procedures.AIM To investigate the impact of patient demographic and clinical characteristics on MDRO acquisition,as well as the impact of MDRO acquisition on intensive care unit(ICU)and hospital length of stay,and on ICU mortality and 1-year mortality post heart transplantation.METHODS This retrospective cohort study analyzed 98 consecutive heart transplant patients over a ten-year period(2013-2022)in a single transplantation center.Data was collected regarding MDROs commonly encountered in critical care.RESULTS Among the 98 transplanted patients(70%male),about a third(32%)acquired or already harbored MDROs upon transplantation(MDRO group),while two thirds did not(MDRO-free group).The prevalent MDROs were Acinetobacter baumannii(14%),Pseudomonas aeruginosa(12%)and Klebsiella pneumoniae(11%).Compared to MDRO-free patients,the MDRO group was characterized by higher body mass index(P=0.002),higher rates of renal failure(P=0.017),primary graft dysfunction(10%vs 4.5%,P=0.001),surgical re-exploration(34%vs 14%,P=0.017),mechanical circulatory support(47%vs 26%P=0.037)and renal replacement therapy(28%vs 9%,P=0.014),as well as longer extracorporeal circulation time(median 210 vs 161 min,P=0.003).The median length of stay was longer in the MDRO group,namely ICU stay was 16 vs 9 d in the MDRO-free group(P=0.001),and hospital stay was 38 vs 28 d(P=0.006),while 1-year mortality was higher(28%vs 7.6%,log-rank-χ2:7.34).CONCLUSION Following heart transplantation,a predominance of Gram-negative MDROs was noted.MDRO acquisition was associated with higher complication rates,prolonged ICU and total hospital stay,and higher post-transplantation mortality.

Antibacterial effect of Allium sativum cloves and Zingiber officinale rhizomes against multiple-drug resistant clinical pathogens

Objective:To evaluate the antibacterial properties ot Allium sativum(garlic) cloves and Zingiber officinale(ginger) rhizomes against multi-drug resistant clinical pathogens causing nosocomial infection.Methods:The cloves of garlic and rhizomes of ginger were extracted with 95%(v/v) ethanol.The ethanolic extracts were subjected to antibacterial sensitivity test against clinical pathogens.Results:Anti-bacterial potentials of the extracts of two crude garlic cloves and ginger rhizomes were tested against five gram negative and two gram positive multi-drug resistant bacteria isolates.All the bacterial isolates were susceptible to crude extracts of both plants extracts.Except Enterobacter sp.and Klebsiella sp.,all other isolates were susceptible when subjected to ethanolic extracts of garlic and ginger.The highest inhibition zone was observed with garlic(19.4S mm) against Pseudomonas aeruginosa(P.aeruginosa).The minimal inhibitory concentration was as low as 67.00 μg/mL against P.aeruginosa.Conclusions:Natural spices of garlic and ginger possess effective anti-bacterial activity against multi-drug clinical pathogens and can be used for prevention of drug resistant microbial diseases and further evaluation is necessary.

Antimicrobial activity of green tea extract against isolates of methicillin-resistant Staphylococcus aureus and multi-drug resistant Pseudomonas aeruginosa

Objective:To evaluate antibacterial activity of the Indonesian water soluble green tea extract,Camellia sinensis,against clinical isolates of methicillin-resistantStaphylococcus aureus (S.aureus)(MRSA)and multi-drug resistant Pseudomonas aeruginosa(MDR-P.aeruginosa).Methods:Antimicrobial activity of green tea extract was determined by the disc diffusion method and the minimum inhibitory concentration(MIC)was determined by the twofold serial broth dilutions method.The tested bacteria using in this study were the standard strains and multi-drug resistant clinical isolates of S.aureus and P.aeruginosa,obtained from Laboratory of Clinical Microbiology,Faculty of Medicine,University of Indonesia.Results:The results showed that the inhibition zone diameter of green tea extracts forS.aureus ATCC 25923 and MRSA were(18.970依0.287)mm,and(19.130依0.250)mm respectively.While the inhibition zone diameter forP.aeruginosa ATCC 27853 and MDR-P.aeruginosawere(17.550依0.393)mm and(17.670依0.398)mm respectively.The MIC of green tea extracts againstS.aureus ATCC 25923 and MRSA were 400μg/mL and 400μg/mL,respectively,whereas the MIC for P.aeruginosa ATCC 27853 and MDR-P.aeruginosawere 800μg/mL,and 800μg/mL,respectively.Conclusions:Camellia sinensisleaves extract could be useful in combating emerging drug-resistance caused by MRSA andP.aeruginosa.

The Roles of Four Multi-drug Resistance Proteins in Hepatocellular Carcinoma Multidrug Resistance

The roles of multi-drug resistance protein 1 （MDR1）, multi-drug resistance related protein 1 （MRP1）, lung resistance protein （LRP） and breast cancer resistance protein （BCRP） in the multi-drug resistance （MDR） of hepatocellular carcinoma （HCC） were studied. By exposing HepG2 cell line to progressively increased concentrations of adriamycin （ADM）, HepG2 multi-drug resistant subline （HepG2/ADM） was induced. The MDR index of HepG2/ADM was detected by using MTT. The expressions of the four MDR proteins in the three cell lines （L02, HepG2, HepG2/ADM） were investigated at mRNA and protein levels by real-time RT-PCR and Western blot respectively. Our results showed that when the ADM concentration was under 100 pg/L, HepG2 could easily be induced to be drug-resistant. The IC50 of the HepG2/ADM to ADM was 282 times that of HepG2. The expression of MDR1 and BCRP mRNA in HepG2/ADM cells were 400 and 9 times that of HepG2 cells respectively while there was no difference in the mRNA expressions of MRPl and LRE There was no difference between HepG2 and L02 cells in the mRNA expressions of the four genes. At the protein level, the expressions of MDRI, BCRP and LRP but MRPl in HepG2/ADM were significantly higher than those of HepG2 and L02. Between HepG2 and L02, there was no difference in the expressions of four genes at the protein level. HepG2/ADM is a good model for the study of MDR. The four genes are probably the normally expressed gene in liver. The expressions of MDRl and BCRP could be up-regulated by anti-cancer agents in vitro. The MDR of HCC was mainly due to the up-regulation of MDR1 and BCRP but MRP1 and LRE These findings suggest they may serve as targets for the reversal of MDR of HCC.

Cytotoxic and antibacterial substances against multi-drug resistant pathogens from marine sponge symbiont:Citrinin,a secondary metabolite of Penicillium sp.

Objective:To Isolate,purify,characterize,and evaluate the bioaclive compounds from the sponge-derived fungus Penicillium sp.FF001 and to elucidate its structure.Methods:The fungal strain FF001 with an interesting bioactivity profile was isolated from a marine Fijian sponge Melophlus sp.Based on conidiophores aggregation,conidia development and mycelia morphological characteristics,the isolate FF001 was classically identified as a Penicillium sp.The bioactive compound was identified using various spectral analysis of UV,high resolution electrospray ionization mass spectra,1H and 13C NMR spectral data.Further minimum inhibitory concentrations(MICs)assay and brine shrimp cytotoxicity assay were also carried out to evaluate the biological properties of the purified compound.Results:Bioassay guided fractionation of the EtOAc extract of a static culture of this Penicillium sp.by different chromatographic methods led the isolation of an antibacterial,anticryptococcal and cytotoxic active compound,which was identified as citrinin(1).Further,citrinin(1)is reported for its potent antibacterial activity against methicillin-resistant Staphylococcus aureus(S.aureus),rifampicin-resistant 5.aureus,wild type S.aureus and vancomycin-resistant Enterococcus faecium showed MICs of 3.90,0.97,1.95 and7.81μg/mL,respectively.Further citrinin(1)displayed significant activity against the pathogenic yeast Cryptococcus neoformans(MIC 3.90μg/mL),and exhibited cytotoxicity against brine shrimp larvae LD_(50)of 96μg/mL.Conclusions:Citrinin(1)is reported from sponge associated Penicillium sp.from this study and for its strong antibacterial activity against multi-drug resistant human pathogens including cytotoxicity against brine shrimp larvae,which indicated that sponge associated Penicillium spp.are promising sources of natural bioactive metabolites.

β-escin reverses multidrug resistance through inhibition of the GSK3β/β-catenin pathway in cholangiocarcinoma

AIM: To develop a safe and effective agent for cholangiocarcinoma(CCA) chemotherapy. METHODS: A drug combination experiment was conducted to determine the effects of β-escin in c o m b i n a t i o n w i t h c h e m o t h e ra p y o n C C A c e l l s. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay was performed to determine the effects of β-escin and common chemotherapeutics on the proliferation of human CCA cells(QBC939, Sk-Ch A-1, and MZ-Ch A-1). Immunocytochemistry was used to detect the expression of P-glycoprotein(P-gp) protein. Luciferase reporter assay was used to detect the activation of the Wnt/β-catenin pathway. The protein levels of P-gp, p S9-GSK3β, p T216-GSK3β, GSK3β, β-catenin, and p-β-catenin were further confirmed by western blotting.RESULTS: The drug sensitivity of QBC939 and QBC939/5-fluorouracil(5-FU) cells to 5-FU, vincristine sulfate(VCR), or mitomycin C was significantly enhanced by β-escin compared with either agent alone(P < 0.05). In addition, the combination of β-escin(20 μmol/L) with 5-FU and VCR was synergic with a combination index < 1. Further investigation found that the m RNA and protein expression of P-gp was downregulated by β-escin. Moreover, β-escin induced GSK3β phosphorylation at Tyr-216 and dephosphorylation at Ser-9, resulting in phosphorylation and degradation of β-catenin. Interestingly, activation of the GSK3β/β-catenin pathway induced by Wnt3 a resulted in upregulation of P-gp, which was effectively abolished by β-escin, indicating that β-escin down-regulated P-gp expression in a GSK3β-dependent manner.CONCLUSION: β-escin was a potent reverser of P-gpdependent multidrug resistance, with said effect likely being achieved via inhibition of the GSK3β/β-catenin pathway and thus suggesting a promising strategy of developing combination drugs for CCA.

Relationship between Methylation Status of Multi-drug Resistance Protein(MRP) and Multi-drug Resistance in Lung Cancer Cell Lines

Objective： To study the relationship between the methylation status of multi-drug resistance protein （MRP） gene and the expression of its mRNA and protein in lung cancer cell lines. Methods： Human embryo lung cell line WI-38, lung adenocarcinoma cell line SPCA-1 and its drug-resistant cells induced by different concentrations of doxorubicin were treated with restriction endonuclease Eco47III. The methylation status of MRP was examined by PCR, and the expressions of its mRNA and protein were evaluated by in situ hybridization and immunohistochemistry. Results： MRP gene promoter region of WI-38 cells was in hypermethylation status, but the promoter region of MRP in SPCA-1 cells and their resistant derivatives induced by different concentrations of doxorubicin were in hypomethylation status. There were significant differences in the expression of MRP mRNA among WI-38 cell line, SPCA-1 cells and their drug-resistant derivatives induced by different concentration of doxorubicin. Consistently, MRP immunostaining presented similar significant differences. Conclusion： The promoter region of MRP in SPCA-1 lung adenocarcinoma cells was in hypomethylation status. The hypomethylation status of 5＇ regulatory region of MRP promoter is an important structural basis that can increase the activity of transcription and results in the development of drug resistance in lung cancer.

In-vitro antimicrobial activity of marine actinobacteria against multidrug resistance Staphylococcus aureus

Objective:To investigate the antibacterial aclivily of marine actinobacteria against multidrug resistance Staphylococcus aureus(MDRSA).Methods:Fifty one actinobacterial strains were isolated from salt pans soil,costal area in Kothapattanam,Ongole,Andhra Pradesh.Primary screening was done using cross-streak method against MDRSA.The bioaclive compounds are extracted from efficient actinobacteria using solvent extraction.The antimicrobial activity of crude and solvent extracts was perfomied using Kirby-Bauer method.MIC for ethyl acetate extract was determined by modified agar well diffusion method.The potent actinobacteria are identified using Nonomura key,Shirling and Gottlieb 1966 with Bergey's manual of determinative bacteriology.Results:Among the fifty one isolates screened for antibacterial activity,SRB25were found efficient against MDRSA.The ethyl acetate extracts showed high inhibition against test organism.MIC test was performed with the ethyl acetate extract against MDRSA and found to be 1 000μg/mL.The isolaled actinobacteria are identified as Streptomyces sp with the help of Nonomura key.Conclusions:The current investigation reveals that the marine actinobacteria from salt pan environment can be able to produce new drug molecules against drug resistant microorganisms.

<i>In Vitro</i>Antibacterial Activity of Flavonoid Extracts of Two Selected Libyan Algae against Multi-Drug Resistant Bacteria Isolated from Food Products

This study aimed to evaluate the antibacterial activity of flavonoids extracted from two Libyan brown algae namely Cystoseira compressa and Padina pavonica using microwave-assisted extraction method against pathogenic bacteria isolated from meat, meat products, milk and dairy products (Staphylococcus aureus subsp. aureus (5 isolates), Bacillus cereus (3 isolates), Bacillus pumilus (1 isolate), Salmonella enterica subsp. enteric (4 isolates) and Enterohaemor-rhagic Escherichia coli O157 (EHEC O157) (4 isolates)). All of these isolates were muti-drug resistant with high MAR index. The results showed that C. compressa extract exhibited better and stronger antibacterial activities against the seventeen tested isolates with inhibition zones diameter ranged from 14 - 22 mm compared to P. pavonica extract which showed positive effect against 9 isolates with low inhibition zone ranged from 11 - 16.5 mm. Flavonoids extracted from C. compressa also displayed the best spectrum of bactericidal effect with a ratio MBC/MIC ≤ 4 obtained on all susceptible tested bacterial strains. Flavonoids and proanthocyanidins significantly contributed to the antibacterial properties. The mode of action of these active extracts is under investigation.

Antibacterial and antioxidant activities of Musa sp.leaf extracts against multidrug resistant clinical pathogens causing nosocomial infection

Objective:To investigate different Musa sp.leave extracts of hexane,ethyl acetate and methanol were evaluated for antibacterial activity against multi-drug resistant pathogens causing nosocomial infection by agar well diffusion method and also antioxidant activities.Methods:The four different Musa species leaves were extracted with hexane,ethyl acetate and methanol.Antibacterial susceptibility test,minimum inhibitory concentration and minimum inhibitory bacterial concentration were determined by agar well diffusion method.Total phenolic content and in vitro antioxidant activity was determined.Results:All the Musa sp.extracts showed moderate antibacterial activities expect Musa paradisiaca with the inhibition zone ranging from 8.0 to 18.6 mm.Among four species ethyl acetate extracts of Musa paradisiaca showed highest activity against tested pathogens particularly E.coli,P.aeruginosa and Citrobacter sp.The minimum inhibitory concentrations were within the value of 15.63-250μg/ml.and minimum bactericidal concentrations were ranging from 31.25-250μg/mL.Antioxidant activity of Musa acuminate exhibited maximum activity among other three Musa species.Conclusions:The present study concluded that among the different Musa species,Musa paradisiaca displayed efficient antibacterial activity followed by Musa acuminata against multidrug resistant nosocomial infection causing pathogens.Further,an extensive study is needed to identify the bioactive compounds,mode of action and toxic effect in.vivo of Musa sp.

Predominance of Multi-Drug Resistant <i>Klebsiella pneumonia</i>and Other Gram Negative Bacteria in Neonatal Sepsis in Equatorial Guinea

The study was conducted on new-born babies in whom septicemia was suspected, to determine the prevalence of bacterial strains isolated and their sensitivity to antimicrobial drugs. The study was carried out at La Paz Medical Center, Microbiology section, Malabo, Equatorial Guinea from August 2013 to October 2015. Out of 293 septicemia suspected cases, 29 (10%) blood cultures were positive, 28 with bacterial growth and 1 with growth of Candida sp. The mortality rate of neonates caused by Gram negative bacterial sepsis was 34.7%. Among the Gram negative bacteria (24 isolates), the most common types were Klebsiella pneumoniae (16 = 69.6%), followed by Escherichia coli (4 = 17.4%) and Acinetobacter species (4 = 17.4%). Four Gram positive bacteria were also isolated and identified all ascoagulase-negative staphylococci. All the Klebsiella pneumoniae isolates and Acinetobacter species demonstrated Multi Drug Resistance against different antibiotics with Extended-spectrum β-lactamase (ESBL) activity. The most frequent causative agent of bacterial sepsis in new-born children was Klebsiella pneumoniae. An alarming level of Multi Drug Resistance (MDR) Klebsiella pneumoniae strains to the first choice antibiotic treatment was observed.

Reversal of HCC Drug Resistance by Using Hammerhead Ribozymes against Multidrug Resistance 1 Gene

To reverse multidrug resistance（MDR） of HepG2 by anti-MDR1 hammerhead ribozyme, an anti-MDR1 hammerhead ribozyme was developed and delivered to P-gp-overproducing human hepatocarcinoma cell line HepG2 by a retroviral vector containing RNA polymerase Ⅲ promoter. The expression of mdrl/Pgp and Rz was detected in HepG2, HepG2 muhidrug-resistant cell line and HepG2 Rz-transfected cells by semi-quantitative RT-PCR and Western blot methods. Moreover, MTT assay was employed to detect the sensitivity of these ribozyme-transfected cells, and Rhodamine123 （Rh123） was used to test the function of Pgp. The Rz- transfected HepG2 cells became doxorubicin-sensitive, which was concomitant with the decreased MDR1 expression. The study showed that the retrovirus vector encoding the anti-MDR1 ribozyme may be applicable to the treatment of MDR cells.

Expression and Prognostic Significance of Multidrug Resistance Associated Protein (MRP) Gene in Non-small Cell Lung Cancer by in Site Hybridization

Objective: To study on the effect of MRP gene overexpression on prognosis of patients with non-small lung cancer (NSCLC). Methods: Paraffin-embedded tissues from 47 cases of NSCLC who had undergone radical tumor resection were examined for expression of MRP gene mRNA by in situ hybridization using labelled digoxigenin probes combined with immunohistochemistry. All the patients were retrospectively followed-up. Results: All of the 47 lung cancer specimens were found to have overexpression of MRP gene mRNA. It was significantly correlated with patients' survival time, response to chemotherapy, recurrence or metastases after surgery, but was not correlated with histology, tumor size, node status, TNM stage, degree of differentiation, age and sex. Conclusion: Overexpression of MRP gene is a marker of prognostic significance in patients with NSCLC.

Multi-Drug Resistance Pattern of Lactose Non-Fermenting <i>Escherichia coli</i>as Causative Agent of Urine Tract Infections in Luanda, Angola

This prospective study was carried out to assess the sensitivity and resistance pattern of lactose non-fermenting Escherichia coli from July 2018 to December 2018 in the Laboratory of Microbiology at Luanda Medical Center, Angola. Out of 1170 patient, a total of 120 urine specimens infected with Escherichia coli (>105 CFU/ml) were collected according to the routine protocol of urinalysis. Among these 120 isolates, 25 (21%) isolates were determined as “atypical”, lactose non-fermenting E. colis trains. The twenty-five lactose non-fermenting Escherichia coli strains isolated from urine samples in Luanda Medical Center were declared as Multiple Drugs-Resistant strains with high resistance to Cefalexine (100%), Cefuroxime (100%), Ceftriaxone (92%), Gentamycin (92%), Ciprofloxacin (72%) and Amoxiciclin/Clavulanic (80%). The alarming resistance level to the first-choice drugs for the treatment of urinary tract infections caused by non-fermentative lactose E. coli was observed.

Molecular characterization of antimicrobial multi-drug resistance in non-typhoidal Salmonellae from chicken and clam in Mangalore, India

Salmonella enterica has been documented as one of the leading causes of salmonellosis throughout the world and is most commonly associated with the consumption of contaminated food products. Thus, this research was aimed at studying the antimicrobial susceptibility pattern and detection of quinolone resistance in Salmonella spp isolated from food of animal origin. Thirty-six Salmonella isolates comprising 8 from poultry and 28 from seafood（clams） were identified, serotyped and characterized for their antimicrobial susceptibility against 10 different antibiotics. Plasmid DNA was isolated from all the isolates by alkaline lysis, quinolone resistant non-typhoidal S. Weltevreden were examined for mutation in the DNA gyrase coding gene. Among the 36 Salmonella isolates, 20 were S. weltevreden（8 from poultry and 12 from seafood） and 16 were S. Typhimurium（from seafood）. All the isolates showed multiple resistance to nalidixic acid, tetracycline, co-trimoxazole and nitrofurantoin, but, interestingly, the isolates were 100% susceptible to ampicillin, chloramphenicol and gentamicin. Resistant isolates from the study carried the genes responsible for resistance to respective antibiotics. The strain S130 isolated in the study showed single point mutation,Asp87Gly, at position 87 in quinolone resistance determining region. It revealed mutation in quinolone resistance determining region as a cause for quinolone resistance in non-typhoidal Salmonellae. The occurrence of genes accountable for plasmid mediated resistance to quinolones（viz., qnrA, qnrB and qnrS） in plasmid of non-typhoidal Salmonellae isolates provides evidence for plasmid mediated quinolone resistance.

Production and purification of a bioactive substance against multi-drug resistant human pathogens from the marine-sponge-derived Salinispora sp.

Objective:To isolate,purify,characterize,elucidate structure and evaluate bioactive compounds from the sponge-derived Salinispora sp.FS-0034.Methods:The symbiotic actinomycete strain FS-0034 with an interesting bioactivity profile was isolated from the Fijian marine sponge Theonella sp.Based on colony morphology and obligatory requirement of seawater for growth,and mycelia morphological characteristics the isolate FS-0034 was identified as a Salinispora sp.The bioactive compound was identified by using various spectral analysis of ultraviolet,high resolution electrospray ionization mass spectroscopy,H nuclear magnetic resonance,correlated spectroscopy and heteronuclear multiple bond coherence spectral data.A minimum inhibitory concentration assay were performed to evaluate the biological properties of the pure compound against multi-drug resistant pathogens.Results:Bioassay guided fractionation of the ethyl acetate extract of the culture of Salinispora sp.FS-0034 by different chromatographic methods yielded the isolation of an antibacterial compound,which was identified as rifamycin W(compound 1).Rifamycin W was reported for its potent antibacterial activity against methicillin-resistant Staphylococcus aureus,wild type Staphylococcus aureus and vancomycin-resistant Enterococcus faecium and displayed minimum inhibitory concentrations of 15.62,7.80 and 250.00 μg/mL,respectively.Conclusions:The present study reported the rifamycin W from sponge-associated Salinispora sp.and it exhibited appreciable antibacterial activity against multi-drug resistant human pathogens which indicated that sponge-associated Actinobacteria are significant sources of bioactive metabolites.

Prevalence of multi-drug resistant uropathogenic Escherichia coli in Potohar region of Pakistan

Objective:To scrutinize patterns of multi-drug-resistant uropathogenic Escherichia coli(UPEC) strains and particularly of fluoroquinolone-resistance this is an alternative choice for the treatment of urinary tract infections.Methods:Bacterial samples(n = 250) were collected from out-patients from August 2012 to August 2014 Islamabad.Antibiotic susceptibility profiling and determination of minimum inhibitory concentrations(MICs) and minimum bactericidal concentrations were performed according to the guidelines of Clinical and Laboratory Standards Institute(CLSI,2012).Genes,qnrA,qnrB and qnrS were identified by DNA amplification and sequencing.Results:The highest percentage of UPEC isolates were resistant to co-trimoxazole(82%) followed by cephalothin(80%),2nd Gen,3rd Gen and 4th Gen cephalosporins,respectively.Resistance against gentamicin,amikacin remained 29% and 4%.For other drugs including nitrofurantoin,tetracycline,carbapenem and beta-lactam inhibitors remained below 10%.Altogether,59% of the isolates were resistant to at least three antibiotics including one fluoroquinolone.Overall,MICs for ciprofloxacin remained(MIC≥256 μg/mL) and for levofloxacin(MIC≥16 μg/mL and 32 μg/mL).No significant differences were observed regarding MIC values of extended spectrumβ-lactamase(ESBL) and non-ESBL producers.For qnrS and qnrB positive isolates MICs remained above 32 μg/mL.Prevalence of UPEC was significantly higher among females and 40% of the isolates were ESBL producers.Conclusions:Higher percentages of ESBL producing UPEC were associated with urinary tract infections.Moreover,the majority of these isolates were multi-drug resistant and fluoroquinolone-resistant.