Mashkoor Mohsin

Effects of ampicillin, gentamicin, and cefotaxime on the release of Shiga toxins from Shiga toxin-producing Escherichia coli isolated during a diarrhea episode in Faisalabad, Pakistan.

The Shiga toxin-producing Escherichia coli (STEC) is an emerging foodborne pathogen. The proportion of cases attributed to STEC in an episode of diarrhea in the Faisalabad region of Pakistan was investigated. In addition, as increase in Shiga toxin (Stx) release after exposure to various antimicrobial agents is widely reported, we also elucidated the in vitro effects of three commonly used antibiotics (ampicillin, gentamicin, and cefotaxime) on Stx release. Isolation and detection of STEC was done using enzyme-linked immunosorbent assay and polymerase chain reaction, followed by phenotypic characterization. In vitro Stx release from isolated STEC was determined using enzyme-linked immunosorbent assay, and Stx-induced verocytotoxicity was quantified using cytotoxicity detection assay. STEC was detected in 5 (21.7%) of 23 patients. Exposure to minimum inhibitory concentration (MIC) of ampicillin, gentamicin, and cefotaxime resulted in a considerable decrease in toxin release and level of cytotoxicity in most of the STEC isolates when compared with control (without antibiotic exposure). Exposure to sub-MIC of ampicillin resulted in a relative increase in Stx release and cytotoxicity (p <or= 0.05) in three of the four isolates tested, whereas a decreasing trend was observed in isolates exposed to sub-MICs of gentamicin and cefotaxime. Sub-MIC of gentamicin resulted in largest decrease in Stx release and a similar trend was observed with cefotaxime to a lesser extent. In conclusion, these in vitro observations suggested that sub-MIC of ampicillin may stimulate Stx release and level of cytotoxicity and therefore should be avoided. Gentamicin did not show such effects and therefore may be considered for STEC antimicrobial therapy.

Multiple drug resistance patterns in various phylogenetic groups of uropathogenic E.coli isolated from Faisalabad region of Pakistan

The objective of this work was the phylogenetic characterization of local clinical isolates of uropathogenic E. coli with respect to drug resistance. A total of 59 uropathogenic E. coli responsible for community acquired urinary tract infections were included in this study. A triplex PCR was employed to segregate each isolate into four different phylogenetic groups (A, B1, B2 and D). Drug resistance was evaluated by disc diffusion method. The drugs used were ampicillin, aztreonam, cefixime, cefoperazone, ceftriaxone, cephradine among β-lactam group; amikacin, gentamicin, and streptomycin among aminoglycosides; nalidixic acid and ciprofloxacin from quinolones; trimethoprim-sulfomethoxazole, and tetracycline. Among 59 uropathogenic E. coli isolates majority belonged to phylogenetic group B2 (50%) where as 19% each belonged to groups A and B1, and 12% to group D. All the isolates were multiple drug resistant (MDR). Most effective drugs against Group A, B1, and B2 were gentamicin, amikacin and cefixime; ceftriaxone and quinolones; and ceftriaxone and amikacin, respectively. Group D isolates were found to be highly resistant to all drugs. Our results have shown emergence of MDR isolates among uropathogenic E. coli with dominance of phylogenetic group B2. However, it was found that group D isolates were though less frequent, more drug resistant as compared with group B2. Groups A and B1 were relatively uncommon. Amikacin, ceftriaxone and gentamicin were the most effective drugs in general.

Description of the First Escherichia coli Clinical Isolate Harboring the Colistin Resistance Gene mcr-1 from the Indian Subcontinent

The first report of plasmid-mediated colistin resistance among Enterobacteriaceae in China sounded alarms in the medical community worldwide ([1][1]). Since then, Escherichia coli isolates harboring colistin resistance encoded by the mcr-1 gene have been globally reported ([2][2]). To our knowledge

Discovery of a mcr-1-bearing plasmid in commensal colistin-resistant Escherichia coli from healthy broilers in Faisalabad, Pakistan

Jiali Lv, Mashkoor Mohsin, Sheng Lei, Swaminath Srinivas, Raja Talish Wiqar, Jingxia Lin, and Youjun Feng School of Food and Biological Engineering, Shaanxi University of Science and Technology, Xi’an, Shaanxi, China; Institute of Microbiology, University of Agriculture, Faisalabad, Pakistan; Department of Medical Microbiology and Parasitology, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China; Department of Biochemistry, University of Illinois, Urbana, USA; College of Animal Sciences, Zhejiang University, Hangzhou, Zhejiang, China

Haematopoietic effects of Angelica sinensis root cap polysaccharides against lisinopril-induced anaemia in albino rats

Abstract Context: Angelica sinensis L. (Umbelliferae) has medicinal properties. Objectives: The present study evaluates the haematopoietic effects of A. sinensis polysaccharides (ASP) against lisinopril-induced anaemia. Materials and methods: Thirty healthy adult male albino rats were randomly divided into five groups (n = 6). Group I was control group. Group II was treated with angiotensin-converting enzyme inhibitor (ACEI, 20 mg/kg/day) to induce anaemia. In group III, erythropoietin (EPO, 100 IU/kg/each) was administered in combination with ACEI. Group IV was treated with ASP (1 g/kg/day), extracted from A. sinensis root caps. In Group V, ASP (1 g/kg/day) was treated with ACEI. After 28 days, blood and tissue samples were collected for haematological and histopathological analysis, respectively. Results: The results showed that ACEI significantly reduced the haemoglobin (Hb, 10.0 g/dL), packed cell volume (PCV, 39.5%), red blood cells (RBCs, 6.2 million/mm3), mean corpuscular volume (MCV, 53.5 fL) and mean corpuscular haemoglobin (MCH, 16.2 pg/cell) values. In the group treated with ASP, the Hb (13.7 g/dL) and RBCs (7.8 million/mm3) increased significantly (p < 0.05). The combination of ASP and ACEI led to the significant (p < 0.05) reduction in Hb (10.7 g/dL), PCV (33.3%), RBCs (6.0 million/mm3), MCV (54.42 fL) and MCH (16.44 pg/cell) values. While histopathological examination of the liver and kidney cells showed a mild degree of toxicity in the ASP-treated group. Conclusion: ASP has a potentiating effect on haematological parameters when given alone. However, when administered simultaneously with lisinopril, it showed an unfavourable effect with more complicated anaemia so it should not be used with ACEIs.

High Prevalence of CTX-M-15-Type ESBL-Producing E. coli from Migratory Avian Species in Pakistan

The increased presence of clinically relevant multidrug resistant bacteria in natural environments is an emerging challenge for global health care. Little is known regarding the occurrence of extended-spectrum beta-lactamase producing Escherichia coli (ESBL-E. coli) from environmental sentinels in Pakistan. The goal of the current study was to gain insights into the prevalence and phylogenetic relationships of ESBL-E. coli recovered from wild birds in Pakistan during winter migration. After initial screening of fecal samples on selective chromogenic agar, ESBL-E.coli were analyzed phenotypically using the Vitek-2 automated system. Genotypic characterization was performed using whole genome sequencing (WGS) followed by an in-depth in silico analysis. Of 150 birds screened, 26 (17.3%) were fecal carriers of ESBL-E. coli. Of these, 88.4% isolates exhibited multidrug resistance (MDR) phenotypes. Resistance to cefotaxime, ceftazidime, ampicillin, doxycycline, tetracycline and sulfamethoxazole/trimethoprim (CTX-CAZ-AM-DC-TE-SXT) represented the most common pattern of MDR (76.9%). WGS data analysis found blaCTX-M-15 as the predominant ESBL genotype (92.3%). Other genes encoding resistance to sulfonamides (sul1/sul2/sul3), aminoglycosides (strA, strB, aadA1, aadA2, aadA5, aac(3)-IId-like, aac(3)-IVa-like and aph(4)-Ia), trimethoprim (dfrA14 or dfrA17), tetracyclines [tet(A)/tet(B)], and fluoroquinolones (qnrS1) were detected commonly, often encoded on IncF-type plasmids (76.9%). ESBL-E. coli were assigned to 17 different sequence types (STs) of which ST10 and ST7097 (4 isolates each) were the most abundant followed by ST4720, ST93, and ST1139 (2 isolates each). Core-genome phylogeny of the isolates found low numbers (0–29) of single nucleotide polymorphisms (SNPs) in isolates belonged to ST7097 originated from two different locations (Chashma barrage and Rasul barrage). Similar trends were found among isolates belong to ST1139. In addition, WGS-based plasmid typing and S1-digestion found plasmids of the same pMLST type (IncF[F-:A-:B53]) and similar sizes in different bacterial and avian hosts suggesting horizontal gene transfer as another possibility for the spread of ESBL-E. coli in avian wildlife in Pakistan.

First Report of bla CTX-M-15-Type ESBL-Producing Klebsiella pneumoniae in Wild Migratory Birds in Pakistan

Abstract We investigated wild migratory birds faecal swabs for extended-spectrum β-lactamases-producing Klebsiella pneumoniae (ESBL-K. pneumoniae) from wetland habitats in Pakistan. ESBL-K. pneumoniae were analysed for MDR phenotype, ESBL genotype and genetic diversity. A total of 13 (8.6%) ESBL-K. pneumoniae were recovered. Of these, 8 (61%) isolates were MDR. DNA sequencing confirmed blaCTX-M-15 as the dominant ESBL genotype. BOX-PCR fingerprints showed most of the isolates are unrelated. This study is the first to report the wildlife contamination of CTX-M-15-producing K. pneumoniae in Pakistan. Due to long-range migration, these birds could be responsible for trans-boundary spread of multidrug-resistant bacteria.

Emergence of Extended Spectrum Beta-Lactamases-Producing Strains Belonging to Cefotaxime-M-1 Class from Intensive Care Units Patients and Environmental Surfaces in Pakistan

Aim : The emergence of multidrug-resistant (MDR) bacteria is the most dangerous threat for the treatment of infectious diseases. The aim of this study was to detect and characterize extended spectrum beta-lactamases (ESBLs) and carbapenemaseproducing Klebsiella pneumoniae and Escherichia coli among patients and environment of intensive care units (ICUs) of three tertiary care hospitals in Pakistan. Materials and Methods : A total of 82 samples from ICUs patients and inanimate environment (injection trays, wash basins, door handles, hand swabs of professionals, and ICU fridges) were screened for ESBL by culturing on CHROMagar-ESBL. ESBL and carbapenemases production were confirmed by double disc synergy test and modified Hodges test, respectively. Polymerase chain reaction was used to detect ESBL encoding genes bla cefotaxime (CTX-M), bla CTX-M-1, bla CTX-M-2, bla CTX-M-9, bla TEM, blaSHV and carbapenemase genes bla KPC, bla New Delhi metallo-beta-lactamase-1, bla OXA-48 and bla VIM. Results : Overall, ESBL production was found high 30/82 (36.5%) among isolates of which 15.8% K. pneumoniae and 20.7% E. coli were identified. All the K. pneumoniae and majority of E. coli isolates were MDR, i.e., resistance to three or more antimicrobial categories. Molecular characterization showed the bla CTX-M-1 as the predominant genotype found in 17/21 (80%) of the isolates. None of the strains was found positive for carbapenemase-encoding genes. Conclusion : In conclusion, this study demonstrates the emergence of MDR ESBL producing strains among ICU patients and hospital environment, posing a serious threat for the control of nosocomial infections.