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Objective(s): The current study aimed to investigate the control and treatment of biofilm-producing isolates of Pseudomonas aeruginosa using silicon nanoparticles (SiNPs). Materials and Methods: Biofilm-producing isolates of P. aeruginosa were recovered from various food samples and identified through fluorescent green colony formation on selective and differential media, as well as the amplification of oprI and oprL genes. Tube methods, Congo-red agar method, and scanning electron microscopy (SEM) were used to study biofilm phenotypes. The effect of SiNPs was evaluated by broth dilution assay. Results: The biofilm assay revealed that these isolates formed biofilms on glass surfaces within 72 hr of incubation. Scanning electron micrographs showed that the biofilm communities were composed of multicellular clusters of P. aeruginosa encased in matrix material. However, these isolates were unable to form biofilms on SiNPs-coated surfaces. The results showed that the planktonic isolates of P. aeruginosa were comparatively sensitive to the antibacterial properties of SiNPs, with minimum inhibitory concentration (MIC) ranging from 100 to 200 μg/ml. Contrarily, the biofilms were found to be 500 times more tolerant to the highest concentration of SiNPs (MIC of 500 μg/ml) and were more resistant. Under static conditions, the sedimentation of SiNPs resulted in their ineffectiveness. However, under shaking conditions, the biofilms were effectively dispersed and the cells were lysed. The results showed that SiNPs were effective against both the planktonic and the metabolically inactive forms of P. aeruginosa. Conclusion: This study suggests that SiNPs could be a useful tool for preventing the formation of biofilms and removing pre-existing biofilms. [ABSTRACT FROM AUTHOR]

Background: Poor hygienic practices, inadequate water supply, and poor sanitary conditions play a major role in the spread of infectious diseases. So, safe drinking water and basic sanitation is of crucial importance to the prevention of health problems. Objects: To study the knowledge, attitude, and practices related to drinking water and sanitation facilities among the urban slum population of different areas of Delhi. Design: Open label, observational, non-randomized, community-based study. Methodology: A cross-sectional study was designed to evaluate the knowledge of 297 females of different slum areas of Delhi regarding sanitation and hygiene, their attitude, and practices were collected using a previously validated questionnaire. The data obtained was analyzed on MS Office (Excel). Major Outcome: Major Outcome: Findings of the study showed that 42% of the subjects had average knowledge and 75 % of the subjects followed unsafe practices on water, sanitation and hygiene. Result: The study was conducted on 297 housewives having mean age as 34.14 years living mostly in joint family with 6000-12000 monthly family income. 76.4% had toilet in their household but lack proper water disposal system. Conclusion: Conclusion: The knowledge and practice on hygiene and sanitation among the households of slum areas of Delhi was found to be satisfactory. This study found significant association between knowledge, practice, age, education, occupation, family income per month. It was observed that young women had good knowledge however financial constrains rule the roast. [ABSTRACT FROM AUTHOR]

The coronavirus disease 2019 (COVID-19) pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has spread globally. COVID-19 presents varied clinical features. The present study focuses on number of patients turning COVID-19 positive, change in Immune Status Questionnaire (ISQ) and WHO quality of life- Bref (WHO Qol – BREF) scales after taking intervention. This open labelled, double arm, controlled, interventional, clinical trial was conducted on high-risk individuals i.e., those residing with a COVID-19 positive member in the identified quarantine area. This twin armed study was conducted on asymptomatic individuals exposed to COVID -19. The test group were prescribed Unani poly-herbal decoction together with Unani formulations Khamira Marwareed and Tiryaq e Arba whereas the control group was not on any intervention. The duration of intervention was 20 days; follow ups were planned on day 10 and day 20. Of the 81 participants enrolled, none of the patients turned COVID-19 positive. However, 13.58% (n=11) developed COVID like symptoms and 70 patients completed the study. The mean age of the participants was 41.42±16.9 years; however, majority of the participants were 18-28 years male with Damvi (Sanguine) temperament. The quality of life of the intervention group improved significantly however, the immune status in both the groups increased with P <0.001. The Unani prophylactic regimen provides a 62% (relative risk reduction) protection against COVID -19. This pilot study paves for a study on a larger population. No adverse effects were observed during the study. Absence of biochemical investigations were limitations to the study. [ABSTRACT FROM AUTHOR]

Objective(s): This study was designed to investigate the effect of AgNPs (10 nm and 30 nm) on different phenotypes of Staphylococcus aureus biofilm consortia. Materials and Methods: A total of eighteen biofilm-producing isolates of Methicillin-Resistant S. aureus (MRSA) were used in the present study. Tube methods, Congo-red agar method, and scanning electron microscopy (SEM) were used to study biofilm phenotypes. Population analysis assay on a tryptone soya agar (TSA) plate was applied to study the different phenotypes of biofilm consortia. The effect of AgNPs was evaluated by broth dilution assay. Results: Results showed that biofilm consortia harbour different phenotypes, i.e., planktonic, metabolically inactive cells, and small colony variants (SCVs) or persister cells. The focus of the present study is the effect of AgNPs on biofilm consortia of MRSA, particularly on the SCVs population. Large size AgNPs (30 nm) were unable to diffuse through extracellular matrix material coverings of the biofilm consortia; they were only active against the planktonic population that occupies the outer surface of consortia. The smaller AgNPs (10 nm), on the other hand, were found to diffuse through the matrix material and hence were effective against planktonic as well as metabolically inactive population of consortia. Moreover, 30 nm AgNPs take 6 hr to disperse off and kill planktonic and upper surface indwellers. The 10 nm AgNPs disperse and kill the majority of biofilm indwellers within 20 min. Conclusion: The present study showed that 10 nm AgNPs can easily penetrate inside the biofilm and are active against all of the indwellers of consortia. [ABSTRACT FROM AUTHOR]

Objective(s): This study was designed to determine the relationship of Pseudomonas aeruginosa, Staphylococcus aureus, and Escherichia coli isolates in multispecies biofilms and their individual phenotypic characters in biofilm consortia. Materials and Methods: The subject isolates were recovered from different food samples and identified on the basis of growth on differential and selective media. Tube methods, Congo-red agar method, and scanning electron microscopy (SEM) were used to study biofilms phenotypes. The hydrophobicity of the strains was evaluated by the adhesion to apolar solvent. Results: The results showed that E. coli dominated the pre-biofilm stage. It has been observed that E. coli adopted biofilm life much before S. aureus and P. aeruginosa. However, after adopting biofilm lifestyle, slowly and gradually, P. aeruginosa dominated the consortia and dispersed other stakeholders. The subject isolates of P. aeruginosa produce cis-2-decanoic acid to disperse or inhibit S. aureus and E. coli biofilms. Gas-chromatography and mass spectrometry results showed that cis-2-decanoic was higher in the co-culture condition and increased at late log-phase or at stationary phase. Although majority of S. aureus were unable to compete with P. aeruginosa, however, a minor population competed, survived, and persisted in biofilm consortia as small colony variants. The survivors showed higher expression of sigB and sarA genes. P. aeruginosa showed comparatively higher hydrophobic surface properties. Conclusion: Comparative analysis showed that cell surface hydrophobicity, growth rate, and small colony variants (SCVs) are correlated in biofilm consortia of the P. aeruginosa, S. aureus, and E. coli. [ABSTRACT FROM AUTHOR]