Multiple antibiotics resistant among environmental isolates of Stenotrophomonas maltophilia

In this study we assessed the functionality of integrons, melanin-like pigment and biofilm formation on multidrug resistance among environmental isolates of Stenotrophomonas maltophilia. Marked resistances were noted against aztreonam (60%), cefepime (68%), ceftazidime (77%), ciprofloxacin (72%), gentamicin (65%), meropenem (75%), piperacillin/tazobactam (65%) in S. maltophilia. Ticarcillin/clavulanic acid (66%) and trimethoprim/sulfamethoxazole (75%) were the active antibiotics against S. maltophilia. Class 1 intergron was significantly detected in 56.3% (54/96) of S. maltophilia strains. Integron-positive strains were significantly resistant to cefepime (69%), ceftazidime (78%), ciprofloxacin (74%), gentamicin (65%), and meropenem (72%). Gene cassettes arrays within integrons were identified as aminoglycoside resistance genes aacA4, aadA2, aadB, aacC4, and aacA6'-Ib; β- lactams resistance genes blaIMP, blaOXA, and blaCARB; chloramphenicol resistance genes cmlA and catB2; quaternary ammonium compound (QAC) resistance genes smr and qac; and multi-gene cassettes: smr/aacA4 and blaIMP/aac6-II/aadA5. High-pigment-producing S. maltophilia strains revealed significant correlation with resistance to cefepime, ceftazidime, ciprofloxacin, levofloxacin and piperacillin/ tazobactam. Biofilm formation was not significant with resistance to ciprofloxacin, levofloxacin, meropenem, ticarcillin/clavulanic and trimethoprim /sulfamethoxazole. Our findings characterize the significant roles of integrons, melanin-like pigment and biofilm formation in the multidrug resistance of S. maltophilia. The range of antibiotics resistance genes and mobile genetic elements found suggests that the organism could potentially act as a reservoir of drug resistance determinants in environmental and clinical settings, which is an issue of public health concern

Antibiotic Synergistic Interaction Against Multidrug Resistant Stenotrophomonas Maltophilia Strains From Environmental Settings

The susceptibility profile of Stenotrophomonas maltophilia strains showed a high phenotypic homogeneity despite their high genomic diversity. Most of the isolates tested were resistant to three or more antibiotics belonging to five different groups. S. maltophilia isolates were resistant to aztreonam (91.3 %), cefepime (85.9%), ceftazidime (86.6 %), ciprofloxacin (81.8 %), gentamicin (88.8 %), levofloxacin (84.8 %), meropenem (93.5 %) and piperacillin/tazobactam (92.9 %). Among the antibiotics tested, ticarcillin/clavulanate acid and trimethoprim/sulfamethoxazole were effective against 88.1% and 92.5% of the isolates respectively. Ninety percent of the isolates were susceptible to trimethoprim-sulfamethoxazole, with MICs at which 50 and 90% of isolates were inhibited (MIC50 and MIC90) of 0.5 and 2 μg ml-1, respectively). Time-kill studies revealed that ticarcillin/clavulanate was bactericidal against S. maltophilia after 3 h of incubation at concentrations equivalent to twice the MIC and 4 times the MIC. Synergism was demonstrated by most pairs of antimicrobial agents. Ticarcillin/clavulanate plus piperacillin/tazobactam inhibited 71.6% of the strains, while trimethoprim/sulfamethoxazole plus ticarcillin/clavulanate inhibited 82.9%, ciprofloxacin plus piperacillin/tazobactam inhibited 69.4% of the strains. Our findings confirm that S. maltophilia exhibited high degree of resistance to the antibiotics tested, and show that trimethoprim /sulfamethoxazole and ticarcillin/clavulanate had good activity against S. maltophilia. Keywords: Bactericidal, synergy, infectious disease, bacteristatic, virulence factor

CD4 count, viral load and parasite density of HIV positive individuals undergoing malaria treatment with dihydroartemisinin in Benin City, Edo state, Nigeria

Background & objectives: A prospective study on 72 HIV infected and 33 HIV negative individualsundergoing malaria treatment with dihydroartemisinin (Cotecxin) was undertaken to compare CD4cells count, viral load and parasite density at two time-points, a baseline visit and a 9-day posttreatmentvisit.Methods: CD4 count and viral load of the subjects were estimated using Dynabeads T4–T8Quantification Protocol (Dyneal Biotech, Norway) and Amplicor HIV-1 Monitor Test respectively(Roche, United Kingdom).Results: There was a significant decrease in CD4 count at 9-day post-treatment when compared withbaseline value (p 200 cells/μl, a marked significant increase was obtained when the mean viral loadat baseline was compared to the 9-day post-treatment visit value (p <0.05). The mean parasite densityin HIV positive subjects was statistically higher when compared to that of HIV negative individualsat baseline and 9-day post-treatment (p <0.05).Interpretation & conclusion: The study as such may not confirm the impact of malaria infection onprogression to AIDS, incorporating effective malaria control in HIV management programmes mayimprove tremendously the quality of life of HIV infected individuals

Prevalence of Lassa virus among rodents trapped in three South-South States of Nigeria

Background & objectives: Lassa fever has been endemic in Nigeria since 1969. The rodent Mastomys natalensis has been widely claimed to be the reservoir host of the Lassa virus. This study was designed to investigate the dis- tribution of species of rodents in three states (Edo, Delta and Bayelsa) of Nigeria and to determine the prevalence of Lassa virus amongst trapped rodents in the selected states. Methods: Rodents were trapped during November 2015 to October 2016 from the three states in South-South re- gion of Nigeria. Total RNA was extracted from the blood collected from the trapped rodents. Reverse transcription polymerase chain reaction (RT-PCR) was used to confirm the presence of Lassa virus in the rodents. Results: The results revealed that six species of rodents were predominantly present in these geographical locations. Mus musculus (39.4%) had the highest prevalence, closely followed by Rattus rattus (36.1%), R. fuscipus (20.3%), M. natalensis (2%), Myosoricinae soricidae (1.2%) and R. norvegicus (1%). The overall positivity (carrier rate) of Lassa virus was 1.6% amongst the 1500 rodents caught in the three states. In Edo and Delta States, the RT-PCR results showed presence of Lassa virus in R. rattus, M. musculus and M. natalensis. On the other hand, only M. na- talensis was detected with the virus, amongst the species of rodents caught in Bayelsa State. M. natalensis recorded the highest Lassa virus among rodents trapped in Edo (87%), Delta (50%) and Bayelsa (11%) States respectively. Interpretation & conclusion: The rather low Lassa virus positive among rodents in Bayelsa State of Nigeria may explain the absence of reports of outbreak of Lassa fever over the past 48 yr in the state. The results also confirmed that apart from Mastomys natalensis, other rodents such as Rattus rattus and Mus musculus may also serve as res- ervoirs for Lassa virus. From the findings of this cross-sectional study, it was concluded that a more comprehensive study on rodents as reservoir host, need to be undertaken across the entire states of Nigeria, for better understanding of the epidemiology and endemicity of Lassa fever

Oil palm (Elaeis guineensis) biomass in Malaysia: The present and future prospects

Oil palm industry is the largest contributor of biomass in Malaysia. Oil palm biomass are constantly generated in large quantities annually with a small fraction being converted into value added product while a large percentage are left underutilized. Several researchers have reported the various technologies available for the conversion of oil palm biomass into useful bio-products, including bio-fuel, biogas, bio-fertilizers, bio-composite and briquettes. In general, these technologies are either underutilized or inadequate for full conversion of these abundantly available biomass, hence, there is an urgent need for upgrading of such technologies. This review article highlights the availability of oil palm biomass in Malaysia, the chemical compositions, as well as a brief description of current technologies for converting oil palm biomass into value added products. The review also outlines a summary of the various products obtained from oil palm biomass. Steps to achieve maximum utilization of biomass from oil palm industry are also proposed