Biofilm analyses and exoproduct release by clinical and environmental isolates of Burkholderia pseudomallei from Brazil

Objective:To characterize biofilm production by clinical(n=21)and environmental(n=11)isolates of Burkholderia pseudomallei and evaluate the production of proteases,hemolysins and siderophores.Methods:Initially,the 32 strains were evaluated for biofilm production in Müller-Hinton broth-1%glucose(MH-1%glucose)and BHI broth-1%glucose,using the crystal violet staining technique.Subsequently,growing(48 h)and mature(72 h)biofilms were evaluated by confocal microscopy.Finally,the production of proteases,hemolysins and siderophores by planktonic aggregates,growing biofilms and mature biofilms was evaluated.Results:All isolates produced biofilms,but clinical isolates had significantly higher biomass in both MH-1%glucose(P<0.001)and BHI-glucose 1%(P=0.005).The structural analyses by confocal microscopy showed thick biofilms,composed of multiple layers of cells,homogeneously arranged,with mature biofilms of clinical isolates presenting higher biomass(P=0.019)and thickness of the entire area(P=0.029),and lower roughness coefficient(P=0.007)than those of environmental isolates.Protease production by growing biofilms was significantly greater than that of planktonic(P<0.001)and mature biofilms(P<0.001).Hemolysin release by planktonic aggregates was higher than that of biofilms(P<0.001).Regarding siderophores,mature biofilms presented higher production than growing biofilms(P<0.001)and planktonic aggregates(P<0.001).Conclusions:Clinical isolates have higher production of biofilms than their environmental counterparts;protease and siderophores seem important for growth and maintenance of Burkholderia pseu­domallei biofilms.

In vitro assessment of the synergism between extracts of Cocos nucifera husk and some standard antibiotics

Objective: To evaluate the interactions between the crude extracts of Cocos nucifera(C.nucifera) and six front line antibiotics(ampicillin sodium salt, penicillin G sodium,amoxicillin, chloramphenicol, ciprofloxacin and tetracycline hydrochloride), against some bacterial pathogens linked with human infection.Methods: The pulverized husk of C.nucifera was dissolved in 95% n-hexane and extracted using Soxhlet extraction method and sterile distilled water(aqueous).The antibacterial susceptibility of the crude extracts of C.nucifera was tested against environmental and clinical strains(6) obtained from the South African Bureau of Standards(SABS), Vibrio(6) and Listeria pathogens(6).The agar-well diffusion method was used for screening the extracts for their antibacterial activity.The minimum inhibitory concentration and minimum bactericidal concentration of the extracts were determined.Time-kill assay was used to evaluate bactericidal and/or bacteriostatic activity.The synergistic effect of the crude extracts and antibiotics was assessed and evaluated by adopting the checkerboard methods.Results: With the time-kill assay, the highest bactericidal activity was observed on Vibrio fluvialis EL041 with a-5.6 ± 0.2 log_(10)CFU/mL decrease in cell density as a result of the combination of the extracts and chloramphenicol at two-fold minimum inhibitory concentrations.Synergisms using the time-kill assay constituted about 72%, while indifference constituted about 28%.The checkerboard method revealed synergistic interaction in 67% of the combinations, and indifference in 33%.There was no specificity in the observed synergy to a particular class of antibiotics.Conclusions: This investigation suggests the crude extracts of C.nucifera to be a potential broad spectrum antimicrobial compound.Therefore, further study is needed to isolate the pure compounds from these crude extracts.

Diagnostic value of combined detection of myocardial markers, white blood cell count and platelet distribution width in patients with positive myocardial injury markers

Objective:To explore the diagnostic value of combined detection of myocardial markers, white blood cell (WBC) counts and platelet distribution width (PDW) in patients with positive myocardial injury markers.Methods: From January 2017 to January 2018, 100 patients with positive markers of myocardial injury in our hospital were selected as observation group, and 100 healthy people were selected as control group. Serum myocardial markers troponin I (cTnI), creatine kinase isoenzyme (CK-MB), myoglobin (MYO), WBC count, and PDW levels were measured at admission, and analyzed for individual indicators. And individual and combined detections of these indicators in early diagnosis of acute myocardial infarction (AMI) were analysed.Results: Serum cTnI, CK-MB, MYO, WBC count and PDW level were higher in the observation group than those in the control group, and the difference between the groups was statistically significant. Of the 100 patients with positive myocardial injury markers, 48 (48.00%) were diagnosed with AMI by final clinical diagnosis. Compared with the control group, the positive rate of serum index and the combined detection of five indicators in the observation group were significantly increased. The sensitivity and specificity of the five indicators combined detection and diagnosis of AMI were 95.83% and 94.23%, respectively, which were higher than the individual detection of each index, and the difference was statistically significant.Conclusions: The combined detection of serum cTnI, CK-MB, MYO, WBC count and PDW is helpful for early diagnosis of AMI and can improve the sensitivity and specificity of diagnosis.

Evaluation of bacterial biomarkers to aid in challenging inflammatory bowel diseases diagnostics and subtype classification

BACKGROUND The challenges for inflammatory bowel disease(IBD)diagnostics are to discriminate it from gut conditions with similar symptoms such as irritable bowel syndrome(IBS),to distinguish IBD subtypes,to predict disease progression,and to establish the risk to develop colorectal cancer(CRC).Alterations in gut microbiota have been proposed as a source of information to assist in IBD diagnostics.Faecalibacterium prausnitzii(F.prausnitzii),its phylogroups,and Escherichia coli(E.coli)have been reported as potential biomarkers,but their performance in challenging IBD diagnostic situations remains elusive.We hypothesize that bacterial biomarkers based in these species may help to discriminate these conditions of complex diagnostics.AIM To evaluate the usefulness of indices calculated from the quantification of these species as biomarkers to aid in IBD diagnostics.METHODS A retrospective study of 131 subjects(31 controls(H);45 Crohn’s disease(CD),25 ulcerative colitis(UC),10 IBS,and 20 CRC patients)was performed to assess the usefulness of bacterial biomarkers in biopsies.Further,the performance of biomarkers in faeces was studied in 29 stool samples(19 CD,10 UC).Relative abundances of total F.prausnitzii(FP),its phylogroups(PHGI and PHGII),and E.coli(E)quantification were determined by qPCR.Loads were combined to calculate the FP-E index,the PHGI–E index and the PHGII-E index.Biomarkers accuracy to discriminate among conditions was measured by the area under the receiver operating characteristic curve(AUC).RESULTS In biopsies,FP-E index was good for discriminating IBS from CD(AUC=0.752)while PHGII-E index was suitable for discriminating IBS from UC(AUC=0.632).The FP-E index would be the choice to discriminate IBD from CRC,especially from all UC subtypes(AUC≥0.875),regardless of the activity status of the patient.Discrimination between UC patients that had the longest disease duration and those with CRC featured slightly lower AUC values.Concerning differentiation in IBD with shared location,PHGI-E index can establish progression from proctitis and left-sided colitis to ulcerative pancolitis(AUC≥0.800).PHG I-E index analysis in tissue would be the choice to discriminate within IBD subtypes of shared location(AUC≥0.712),while in non-invasive faecal samples FP or PHGI could be good indicators(AUC≥0.833).CONCLUSION F.prausnitzii phylogroups combined with E.coli offer potential to discriminate between IBD and CRC patients and can assist in IBD subtypes classification,which may help in solving IBD diagnostics challenges.

Global evolution of organochlorine pesticides research in biological and environmental matrices from 1992 to 2018:A bibliometric approach

The analysis of organochlorine pesticides(OCPs)in ecosystem components has been a major niche area among environmental scientists,probably due to their endocrine-disruptive properties.Here,we evaluated the global research productivity of OCPs research from 1992 to 2018 using various bibliometric indices.A total of 2326 articles that focused on OCPs research in biological and environmental matrices were retrieved from the Web of Science(WoS).A steady progression on OCPs article production was noticed during the survey period with regression and Lokta distribution models suggesting that more research outputs on this pollutant class is imminent in years to come.The People's Republic of China and the United States were respectively ranked first and second in both‘most productive countries’and‘countries with the highest number of citations.’Not surprisingly,these two countries also had the most collaborative network with not less than ten collaboration linkages with other countries.This study shows the high involvement of OCPs research from scientists domiciled in developed countries.However,international collaboration should be encouraged particularly between developed and developing countries.To this end,more research programs should be established to monitor OCPs in regions where they have been used in the past especially in Africa.This bibliometric survey will assist policymakers and researchers in designing future research and allocating funds involving OCPs research.

Wastewater treatment plants and release:The vase of Odin for emerging bacterial contaminants,resistance and determinant of environmental wellness

Municipal wastewater consists of a downstream collection of flushed sewage(without solid waste),other household runoffs,industrial runoffs,hospital runoffs and agricultural runoffs through an underground pipe before treatment.A runoff collection system called the wastewater treatment plant(WWTPs)treats such wastewater before release into environment following specific regulatory standards.This years-long practice has been improved upon by adding end-to-end pipe technologies with a view to enhancing the quality of effluent released.However,effluents released into the environment from design/application of WWTPs appear to contain emerging contaminants of both biotic and abiotic nature.The observation of chemical contaminants,antibiotic resistant bacteria(ARB),antibiotic resistant genes(ARGs)and diverse pathogenic bacteria genera in wastewater works release further affirm the abundance of such emerging contaminants.As a result,the government and water regulatory organizations in various part of the world are considering the removal of water reuse act from recycling policy/process.Current global debate is focused on questions about sustenance of any improved additional treatment level;effect of energy consumption by added treatment stage and its impact on the environmental wellness as contaminants borne wastewater is consistently released.Technological advancement/research suggests implementation of newer innovative infrastructural systems(NIIS)such as Mobbing Bed Biofilm Rector(MBBR),for wastewater effluent management which involve addition of newer wastewater treatment stages.This review addressed current pitfalls including wastewater microbiota of high epidemiological/public health relevance and affirms the need for such improvement which requires modification of ongoing institutional framework with a view to encourage implementation of NIIS for an improved effluent release.Exploiting the advances of microbial biofilming and the potentials of microbial biofueling as discussed in various section promises a future of robust environmental system,stable operational standard,release of quality effluent and sustainable management of wastewater works.Application of the aforementioned would enhance qualityWWTPs release and in-defacto reduces spread of ARB/ARGs as well as impacts both the environment wellness and public health.

Occurrence and distribution of pharmaceuticals in surface water and sediment of Buffalo and Sundays River estuaries, South Africa and their ecological risk assessment

This study investigated the presence of pharmaceuticals in the water and sediment of Buffalo and Sundays River Estuary,South Africa.Extraction for water and sediment samples was achieved with solidphase extraction and ultrasonic extraction methods,respectively.Quantification of the target analytes was done with UPLC-QTOF-MS.The pH of surface water in all the sampling sites(8.18-10.1)were above the WHO guideline(6.5).A good correlation was observed between the concentrations of analytes with organic matter and organic carbon.Results showed that carbamazepine exhibited the highest concentration(8.75±1.45 mg/kg)of all the pharmaceuticals,while trimethoprim has the highest detection frequency with the highest concentration of 1.62±0.83 mg/kg in the sediment samples.Sulfamethoxazole was below the detection limit in both estuaries.Calculated risk quotients revealed that carbamazepine and trimethoprim could be of potential risk,while caffeine may pose a very low risk to the aquatic organisms investigated.Proper monitoring of the runoff entering Buffalo Estuary is required,being the point of discharge of Buffalo River to the Indian Ocean.Also,the domestic waste discharge from residences in the surroundings of Sundays Estuary should be monitored.