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.

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.

<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.

Detection of Multi-drug Resistant Acinetobacter Lwoffii Isolated from Soil of Mink Farm

There were 4 Acinetobacter lwoffii obtained from soil samples.The antimicrobial susceptibility of the strains to 16 antimicrobial agents was investigated using K-B method.Three isolates showed the multi-drug resistance.The presence of resistance genes and integrons was determined using PCR.The aadA 1,aac（3＇）-IIc,aph（3＇）-VII,aac（6＇）-Ib,sul2,cat2,floR,and tet（K）genes were detected,respectively.

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.

Bacterial contamination of orally-consumed crude herbal remedies:A potential source for multi-drug resistant pathogens in man

Objective:The acceptability of herbal remedies for alleviating discomforts and ill-health has become very popular, on the account of the increasing cost of allopathic medicine for personal health maintenance.The observable non-adherence of herbalists to the established World Health Organization(WHO) / National Agency for Food and Drug Administration Control(NAFDAC) regulations for the quality control of herbal medicines is an issue for concern.In view of this,34 popular and widely consumed crude herbal remedies in southwestern,Nigeria were screened for compliance with standard limits for bacterial contamination,bacteria flora and their antibiotic susceptibility pattern.Methods:Isolates recovered from samples were identified using the cultural, morphological and biochemical characteristics.They were also tested for drug sensitivity using standard procedures. Results:A heavy bacteria load ranging from 3.00×10~3-9.58×10~5 CFU/ML and 1.20×10~5- 5.41×10~5 CFU/ML was observed for water and spirit extracted preparations respectively.The bacteria flora cum contaminants were:Staphylococcus aureus,Bacillus cereus,Bacillus subtilis,Pseudomonas aeruginosa, Micrococcus luteus,Lactobacillus plantarum,Klebsiella pneumoniae,Escherichia coli,streptococcus,Shigella, Neisseria,Arthrobacter,Kurthia and Clostridium species.All the isolates were multi-drug resistant(MDR) strains.Conclusion:The crude herbal preparations consumed in Nigeria failed to comply with the internationally recognized standards regarding bacteria load and flora.The presence of MDR pathogens is of greatest concern. It poses a great risk to consumers health and could be a source of introducing MDR organisms into the human population.There is the need for the enforcement of established guidelines to ensure the safety of these preparations.

Molecular characteristics,antibiogram and prevalence of multi-drug resistant Staphylococcus aureus (MDRSA) isolated from milk obtained from culled dairy cows and from cows with acute clinical mastitis

To study the molecular characteristics, antibiogram and prevalence of multi-drug resistant Staphylococcus aureus (S. aureus) (MDRSA) isolated from milk obtained from culled dairy cows and from cows with acute clinical mastitis.MethodsBacteria were cultured from 188 quarter milk samples obtained from cows before culling (n = 139) and from cows affected with acute mastitis (n = 49) belonging to 10 dairy farms. The bacteria were identified using colony morphology, Gram staining and biochemical characteristics. S. aureus isolates were then subjected to molecular characterization using PCR targeting 16S rRNA and mecA gene to identify Methicillin resistant S. aureus (MRSA). The antibiogram of all isolates was performed using the Kirby-Bauer disk diffusion method against 10 commonly used antibiotics in dairy farms.ResultsS. aureus was isolated from 19 (13.7%) samples obtained from culled cows and 11 (22.4%) samples obtained from cows with acute mastitis. In both culled cows and cows with acute mastitis, in vitro antibiogram revealed that 100% of S. aureus isolates were resistant to erythromycin, penicillin G, streptomycin, doxycyclin, and trimethoprim/sulpha. The prevalence of MRSA in milk of culled cows and cows with acute mastitis was 26.3% and 18.2%, respectively, with an overall prevalence of 3.7% among all samples. All MRSA isolates were completely resistant to all tested antibiotics. All MRSA isolates were positive for the presence of the mecA gene.ConclusionsMRSA carrying the mecA gene were isolated from mastitic milk from dairy cows in Jordan for the first time. MRSA may pose a potential health risk to the public, farm workers and veterinarians.

The difference between multi-drug resistant cell line H460/Gem and its parental cell NCI-H460

Objective： To discuss the difference between multi-drug resistant cell line H460/Gem and its parental cell NCl-H460 on the basis of establishment of human gemcitabine-resistant cell line H460/Gem so as to elaborate the possible mechanisms of gemcitabine resistance. Methods： Human gemcitabine-resistant non-small cell lung cancer cell line H460/Gem was established by 2/3 clinical serous peak concentration gemcitabine intermittent selection from its parental cell human large cell lung carcinoma cell line NCl-H460 which was sensitive to gemcitabine. During the course of inducement, we had monitored their morphology, checked their resistance indexes and resistant pedigree by MTT method, gathered their growth curves and calculated their doubling time, examined their DNA contents and cell cycles by FCM; at the same time, we had measured its expressions of P53, EGFR, c-erb-B-2, PTEN, PCNA, c-myc, VEGF, MDR-1, Bcl-2, nm23, MMP-9, TIMP-1, CD44v6 proteins via immunocytochemistry staining, RRM1 and ERCC1 mRNA by real-time fluorescent quantitative-PCR. Results： The resistance index of H460/Gem＇ cells （the deputy of cells in the process of inducement） to gemcitabine was 1.201, and the cell line also exhibited cross-resistance to paclitaxol, fluorouraci, etoposide, cisplatin and oxaliplatin, but kept sensitivity to vinorelbine and taxotere. The doubling time of H460/Gem＇ cells was longer and figures in G0-G1 phase was decreased than that of NCl-H460 cells. Compared with NCl-H460 cells, H460/Gem＇ cells had achieved TIMP-1 protein expression emerged, nm23 protein expression enhanced, VEGF and MMP-9 protein expressions reduced, and CD44v6, P53 protein expressions vanished, but expressions of EGFR, c-erb-B-2, PTEN, PCNA, c-myc, MDR-1, Bcl-2 proteins and RRM1, ERCC1 mRNA changed trivially. The resistance index of H460/Gem cells to gemcitabine was 1.644, and the ceil line also exhibited cross-resistance to fluorouraci, cisplatin and oxaliplatin, but kept sensitivity to paclitaxol, vinorelbine, taxotere, and etoposide. The doubling time of H460/Gem cells was longer and figures in G0-G1 phase was decreased than those of NCl-H460 cells. The farther studies indicated that, compared with NCl-H460 cells, the expressions of MDR-1, nm23 and Bcl-2 proteins in H460/Gem cells had been enhanced, c-erb-B-2 protein expression emerged, P53, MMP-9 and VEGR protein expression had been weakened, but the changes of PTEN, PCNA, c-myc, TIMP-1, EGFR, CD44v6 protein, RRM1 mRNA and ERCC1 mRNA expressions were trivial. Furthermore, compared with its parental cells, H460/Gem cells were mixed with giant cells of different sizes that were larger and more irregular. Conclusion： The human gemcitabine-resistant non-small cell lung cancer cell line H460/Gem had achieved multi-drug resistance and great changes of biological characters compared with its parental cells. And these changes possibly participated in the formation of multidrug resistance.

The difference between multi-drug resistant cell line A549/Gem and its parental cell A549

Objective:To discuss the difference between multi-drug resistant cell line A549/Gem and its parental cell A549 on the basis of establishment of human gemcitabine-resistant cell line A549/Gem so as to elaborate the possible mechanisms of gemcitabine resistance.Methods:Human gemcitabine-resistant non-small cell lung cancer cell line A549/Gem was estab-lished by the method of repeated clinical serous peak concentration plus gradually increasing concentration of gemcitabine from its parental cell human lung adenocarcinoma cell line A549 which was sensitive to gemcitabine.During the course of inducement,we had monitored their morphology,checked their resistance indexes and resistant pedigree by MTT method,gathered their growth curves and calculated their doubling time,examined their DNA contents and cell cycles by FCM;at the same time,we had measured their expressions of P53,EGFR,Cerb-B-2,PTEN,PCNA,c-myc,VEGF,MDR-1,Bcl-2,nm23,MMP-9,TIMP-1,and CD44v6 proteins via immunocytochemistry staining,RRM1 and ERCC1 mRNA by real-time fluorescent quantitative-PCR.Results:The resistance index of A549/Gem' cells(the deputy of cells in the process of inducement) to gemcitabine was 163.228,and the cell line also exhibited cross-resistance to vinorelbine,taxotere,fluorouraci,etoposide and cisplatin,but kept sensitivity to paclitaxol and oxaliplatin.The doubling time of A549/Gem' was shorter and figures in G0-G1 phases were increased than A549 cells.Compared with A549 cells,A549/Gem' cells achieved EGFR and c-myc proteins expressions,nm23 protein expression enhanced,P53,Cerb-B-2 and Bcl-2 proteins expressions reduced,PTEN,PCNA and MDR-1 proteins expressions vanished,but those of MMP-9,VEGF,CD44v6 and TIMP-1 proteins changed trivially.Meanwhile,expressions of RRM1 and ERCC1 mRNA were augmented markedly.The resistance index of A549/Gem cells to gemcitabine was 129.783,and the cell line also held cross-resistance to vinorelbine,taxotere,etoposide,cisplatin and sensitivity to paclitaxol.But the resistance to fluorouracil and sensitivity to oxaliplatin vanished.And the expression of RRM1 and ERCC1 mRNA decreased visibly.The doubling time of A549/Gem cells was longer and figures in G0-G1 phases were decreased than A549/Gem' cells.In A549/Gem cells,expressions of P53,EGFR,PCNA and MDR-1 proteins was same to those of A549/Gem' cells.A549/Gem cells achieved TIMP-1 and PTEN proteins expressions,Cerb-B-2,MMP-9,c-myc and Bcl-2 proteins expressions enhanced,nm23 protein expressions vanished,but the expressions of VEGF and CD44v6 proteins changed trivially.Furthermore,Compared with its parental cell A549,A549/Gem cell was mixed with giant cells of different sizes and was larger and more irregular.Conclusion:The human gemcitabine-resistant non-small cell lung cancer cell line A549/Gem had achieved multi-drug resistance and great changes of biological characters compared with its parental cells A549.And these changes possibly participated in the formation of multidrug resistance.

Management of Multi-Drug Resistant Methicillin Resistant <i>Staphylococcus aureus</i>Induced Pneumonia with New Antibiotic Adjuvant Entity: A Retrospective Study

Aim/Objective: Increase in incidences of pneumonia due to multi-drug resistant methicillin resistant Staphylococcus aureus (MRSA) in both community and health care settings is of great concern globally. Present study aims to retrospectively analyze the efficacy of new fixed dose combination with antibiotic adjuvant entity (FDC) in comparison with vancomycin to treat patients with multi-drug resistant MRSA pneumonia. Materials and Methods: During this retrospective study, case sheets of patients who were treated for MRSA pneumonia with vancomycin or fixed dose combination of vancomycin + ceftriaxone + adjuvant (FDC) between 20 March 2010 to 20 October 2014 at tertiary care center, were analyzed. Various demographic features, antibiotic therapy, length of treatment duration and the resulting efficacy were evaluated. Microbiological success was measured in terms of bacterial eradication, while clinical success was monitored in terms of complete omission of systemic signs and symptoms. Results: Among 136 patients analyzed, 113 cases were having positive culture for MRSA, and hence were further analyzed. Out of these 113 patients, empirical treatment with vancomycin was given in 59 patients and 54 patients were treated with FDC empirically. After initial culture reports, 22 patients showing resistance to vancomycin were shifted to FDC. Amidst all the patients, 24 (64.86%) of 37 from vancomycin group and 62 (81.57%) of 76 from FDC group achieved clinical success. 9 patients out of these failure cases were cured with FDC + colistin combination therapy. Failure rates in FDC treated patients were significantly low (6.57%) as compared to vancomycin group (13.51%). Conclusion: For the treatment of different types of multi-drug resistant MRSA pneumonia, the empirical intravenous FDC therapy was safe and well tolerated with higher efficacy than vancomycin. Most of the vancomycin failure cases responded to FDC therapy and were cured. This retrospective study also concludes that an alternative option of FDC + colistin is safe and effective to treat the patients which fail to respond to FDC monotherapy.

Isolation of Multi-Drug Resistant Paenibacillus sp. from Fertile Soil： An Imminent Menace of Spreading Resistance

There are a good number of reports in the literature stating spread of resistance from normal soil flora to nosocomial microorganism through various ways. Similarly during the study of antimicrobial susceptibility pattern in the microflora, a multidrug resistant bacterium has been isolated from soil collected in Maharashtra state （India）. The bacterium exhibited a resistance to various classes of antibiotics namely glycopeptide, beta-lactams, aminoglycosides, macrolides and lincosomides. The bacterial strain showed its resemblance to the genus Paenibacillus. This constitutes the first report of its kind as to the multi-drug resistance trait in the genus Paenibacillus phenotype, especially in close phylogenetic neighbour of Paenibacillus daejeonensis. The resistance pattern displayed by this strain particularly highlights the possible presence of multiple resistant determinants in microflora of the soil rhizosphere. In view of the recent reports about the Paenibacillus spp. in clinical derived strains, such multi-drug resistance factors in this genus adds to menace of transmission of resistance to common soil originating pathogen. The data also supports the fact that the resistances to certain antibiotics need not always be due to exposure to particular antibiotic or similar substance.

Occurrence of Multi-Drug Resistant <i>Listeria species</i>in Faecal Samples of Poultry Chickens in Rural Farms in Lagos State, Nigeria

Background: Listeriosis is a common zoonotic disease caused by a foodborne pathogen, Listeria monocytogenes. Poultry meat and products have been established as vehicles of transmission of pathogenic Listeria strains to humans. This study evaluates the occurrence of Listeria species in faeces of poultry chicken in Lagos. Methods: One hundred and fourteen pooled fresh faecal samples from cage-reared broiler chickens were collected from 12 farms in three rural areas in Lagos State from May to August 2019. All samples were analysed for Listeria species detection according to ISO11290-1 standard and confirmed using PCR assay. Susceptibility testing was performed using the Kirby-Bauer disc diffusion technique. Results: Twenty-eight (24.6%) Listeria species were detected from 114 faecal samples. The isolated Listeria species were L. monocytogenes 8 (7.0%), L. ivanovii 9 (7.9%), L. grayi 7 (6.1%) and L. innocua 4 (3.5%). There was no significant difference in the frequency of occurrence of Listeria species across the different locations (X2 = 4.98, p = 0.08). The listeria species were susceptible to Augmentin (96.4%), vancomycin (85.7%) and co-trimoxazole (82.1%), but resistant to ceftazidime (100%), tetracycline (75.0%) and ciprofloxacin (71.4%). Conclusion: This study reveals high occurrence of multi-drug resistant Listeria species in faecal samples of poultry chickens in Lagos state which may be an important vector in the contamination of the environment and transmission of antibiotic resistant Listeria species to consumers.

In Vitro Anti-tuberculosis Activity of Total Crude Extract of Echinops Amplexicaulis against Multi-drug Resistant Mycobacterium Tuberculosis

Background： TB （Tuberculosis） is the second leading killer infectious disease after HIV （human immunodeficiency virus）. Its incidence is worsened by development of multi-drag resistant and extensive drug resistant TB stxains. Available treatment regimens are expensive, toxic and lengtjy resulting to problems of non-adherence and inadequate response. Medicinal plants on the other hand may offer hope for developing alternative medicine for treatment of TB. This study evaluated the anti-tuberculosis activity of Echinops amplexicaulis. Materials and methods： Total crude extracts ofE. amplexicaulis were tested for activity against a wild strain resistant to Rifampicin and Isoniazid （MDR）, a fully susceptible laboratory strain （H37Rv） and Mycobacwrium boris （BCG strain） using disk diffusion method. MIC （minimum inhibitory concentration） was determined using Middlebrook 7H9 broil1. The strains were sub-cultured on Middlebrook 7H10 medium and MBC （minimum bactericidal concentration） determined. Susceptibility was evaluated by measuring zones of inhibition; MIC was obtained as the lowest concentration with no significant growth as shown by clog formation ofMTB （Mycobacwria tuberculosis） cells on the walls of the macro broth tube and MBC was obtained as the lowest concentration that inhibited growth of MTB colonies on Middlebrook 7H10 medium. Results： The extract showed a significant effect at a concentration of 50 mg/mL against all the three test strains F （2, 18） = 437.7, p = 0.00. It exhibited a MIC of 0.0488 mg/mL against MDR-TB and M. boris. Its MBC was the same at 0.0977 mg/mL against both MDR TB and M. boris. The MIC was much lower （0.0122 mg/mL） for the H37Rv strain. Terpenoids, alkaloids and tannins were present in large amount in the extract while saponins were present in small amounts. Flavonoids were not detected in the extract. Conclusion： E. amplexicaulis has the potential to be developed into new anti-TB drug and outcome of tile study supports the folkloric claims of anti-tuberculosis activity of tile plant.

Direct and Residual Microbicidal Efficacy of Various Antiseptics against Multi-Drug Resistant Bacteria

Background: Infections in ICU’s patients are known to often originate from the colonization of wounds by the patient’s endogenous microbiota, and to eventually lead to secondary sepsis. Aim: to compare in vitro the direct and residual effects after different exposure times of 4% chlorhexidine, and of 0.1% and 0.04% polyhexanide (in gel and solution forms), on ATCC-microorganisms, and too, on bacterial strains obtained from ICU patients. Methods: We used wild multi-drug resistant strains recently obtained from the wounds of patients hospitalized at ICU and reference strains from the American Type Culture Collection (ATCC). Chlorhexidine 4% was studied as a reference solution. The direct and residual effects of the 0.1% and 0.04% polyhexanide, in gel and solution forms, were analyzed using cotton germ carriers. To evaluate the direct effect, we exposed the strains to the antiseptic. To assess the residual effect, the germ-carriers were impregnated with antiseptic and were allowed to dry before we contaminated them. We inoculated the germ carriers in a culture medium with an inhibitor of antiseptic effect to count the number of surviving microorganisms. Findings: 0.1% Polyhexanide solution proved a direct and residual efficacy after 24 hours equivalent to 4% chlorhexidine. Is very important to highlight that this great efficacy did not change according to whether they were ATCC or multidrug-resistant strains. Conclusions: 0.1% polyhexanide demonstrated a great direct and residual efficacy (like 4% chlorhexidine), against multi-drug resistant strains isolated from ICU’s patients. Moreover, due to its few cytotoxicity against keratinocytes and fibroblasts can be an optimal antiseptic for burns, wounds or ulcers.

Analysis of Multi-Drug Resistant Organism Surveillance and Antimicrobial Resistance Early Warning in a Hospital in 2022

Objective:To determine the clinical distribution of multi-drug resistant organism(MDRO)in Jiangyan Hospital and the monitoring and warning of drug-resistance bacteria to provide an important basis for guiding the application of broad-spectrum antibiotics in clinical treatment and reducing the occurrence of nosocomial infection.Methods:Retrospective screening and analysis were conducted on the pathogenic strains of hospitalized patients in our hospital in 2022.Results:A total of 2,769 strains of pathogenic bacteria and 390 strains of MDRO were detected and isolated in our hospital in 2022;the detection rate of MDRO was 14.08%.A total of 516 strains(18.64%)Klebsiella pneumoniae(KP)and 62 strains(12.02%)of carbapenem-resistant Klebsiella pneumoniae(CR-KP)were detected;436 strains(15.75%)of Escherichia coli(ECO)were detected,including 8 strains(1.83%)of CR-ECO;342 strains(12.35%)of Pseudomonas aeruginosa(PA)and 116 strains(33.92%)of CR-PA were detected;there were 194 strains(7.01%)of Acinetobacter baumannii(AB),among which 125 strains(64.43%)were CR-AB;there were 291 strains(10.51%)of Staphylococcus aureus,among which 79 strains(27.15%)of methicillin-resistant Staphylococcus aureus(MRSA)were detected;78 strains(2.82%)of Enterococcus faecalis were detected,and vancomycin-resistant enterococcus(VRE)was not detected.The first five MDROs were CR-AB,CR-PA,MRSA,CR-KP,and CR-ECO.The top five departments with the highest MDRO detection rate in 2022 were the ICU(37.44%),the Pulmonology Department(ward 13;31.03%),the Department of Rehabilitation(ward 5;6.67%),the Department of Neurosurgery(ward 11;4.62%),and the Department of General Surgery(ward 10;3.59 The resistance rate of antibacterial drugs is divided into four levels for early warning:30%to 40%,41%to 50%,51%to 75%,and 75%or more.Conclusion:Our hospital should strengthen the monitoring of antimicrobial resistance warning related to MDRO and the abuse of antimicrobial drugs.Based on the results of drug sensitivity and antimicrobial resistance warning,the use of antibiotics should be standardized in clinical practice to reduce nosocomial infection。

Analysis of Clinical Symptoms Improvement in Treatment of Severe Pneumonia Caused by Multi-drug Resistant Bacterial Infection by Bronchoscopy Alveolar Lavage

Objective:To explore the effects of bronchoscopy alveolar lavage in the treatment of severe pneumonia caused by multiple drug bacterial infection.Methods:A total of 84 patients with severe pneumonia infected by multi-drug resistant bacteria were randomly selected from Kunming Second People's Hospital,which is our hospital from January 2019 to December 2020 for this research.They were divided into a reference group and a study group using a digital table method,with 42 cases in each group.The reference group was given the routine treatment,the research group performed bronchoscopy alveolar lavage on this basis to observe the curative effect.Results:Before treatment,there was no significant difference in serum factor indexes and blood gas analysis indexes between the two groups of patients,P>0.05.After treatment,the time of fever,cough,moist rales disappearing and infection control time in the study group were shorter than those in the reference group,P<0.05.Serum tumor necrosis factorα(TNF-α),interleukin-6(IL-6)and interleukin-8(IL-8)levels were lower than the reference group,and the arterial partial pressure of oxygen(PO2)and oxygen saturation(SO2)were both lower than the reference group,P<0.05.The effective rate of the treatment in the study group was higher than that in the reference group,P<0.05.Conclusion:Bronchoscopic alveolar lavage treatment can effectively improve the clinical symptoms of patients with severe pneumonia caused by multi-drug resistant bacterial infection,and the effects are significant.

Acceleration of apoptosis by transfection of bak gene in multi-drug resistant (MDR) bladder cancer cellsI

Objective To observe the effects of bak gene on killing MDR bladder cancer cells and to study its mechanisms. Methods Bak gene was transfected into MDR bladder cancer cells by liposome. The mRNA of bak and bcl-2 were detected by in situ hybridization. The protein of bak and bcl-2 were detected by SABC immunohistochemistry. The growth rate of human bladder cancer cells was studied by constructing the growth curve, cell apoptosis being observed by flow cytometry, and the outline of cells observed by fluorescence stain. Results The expression of bak mRNA was positive in EJ/bak cells (64% ,P【0.05).Bak protein expression of EJ/bak cells was positive (60 % ) and bcl-2 protein expression was de creased (P【0.05). The growth of MDR bladder cancer cells was significantly inhibited by 32% after bak gene was transfected (P 【 0. 05 ). Apoptosis cells increased significantly. The apoptosis rate was 35 %. Apoptotic bodies can be found in these cells on fluorescence stain. Conclusion Bak gene could inhibit the growth

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.

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.