Genotypic diversity in multi-drug-resistant E. coli isolated from animal feces and Yamuna River water, India, using rep-PCR fingerprinting.

Genotypic diversity among multi-drug-resistant (MDR) aquatic E. coli isolated from different sites of Yamuna River was analyzed using repetitive element PCR (rep-PCR) methods viz. ERIC-PCR and (GTG)5-PCR and compared with the MDR animal fecal isolates. The 97 E. coli isolates belonging to different serotypes, phylogroups, and multi-drug resistance patterns were analyzed. High genetic diversity was observed by both the methods; however, (GTG)5 typing showed higher discriminating potential. Combination of ERIC types (E1-E32) and (GTG)5 types (G1-G46) generated 77 genotypes. The frequency of genotypes ranged from 0.013 to 0.065. The genotype composition of E. coli isolates was highly diverse at all the sampling sites across Yamuna River except at its entry site in Delhi. The sampling sites under the influence of high anthropogenic activities showed an increase in number of unique genotype isolates. These sites also exhibited high multiple antibiotic resistance (MAR) indexes (above 0.25) suggesting high risk of contamination. Principal coordinate analysis (PCoA) showed limited clustering of genotypes based on the sampling sites. The most frequent genotypes were grouped in the positive zone of both the principal coordinates (PC1 and PC2). The genotypes of most of the animal fecal isolates were unique and occupied a common space in the negative PC1 area forming a separate cluster. High genotypic diversity among the aquatic E. coli and the drain isolates, discharging the untreated municipal waste in the river, was observed, suggesting that the sewage effluents contribute substantially to contamination of this river system than animal feces. The presence of such a high diversity among the MDR E. coli isolates in the natural river systems is of great public health significance and highlights the need of an efficient surveillance system for better management of Indian natural water bodies.

NU-6027 Inhibits Growth of Mycobacterium tuberculosis by Targeting Protein Kinase D and Protein Kinase G.

Tuberculosis (TB) is a global health concern, and this situation has further worsened due to the emergence of drug-resistant strains and the failure of BCG vaccine to impart protection. There is an imperative need to develop highly sensitive, specific diagnostic tools, novel therapeutics, and vaccines for the eradication of TB. In the present study, a chemical screen of a pharmacologically active compound library was performed to identify antimycobacterial compounds. The phenotypic screen identified a few novel small-molecule inhibitors, including NU-6027, a known CDK-2 inhibitor. We demonstrate that NU-6027 inhibits Mycobacterium bovis BCG growth in vitro and also displayed cross-reactivity with Mycobacterium tuberculosis protein kinase D (PknD) and protein kinase G (PknG). Comparative structural and sequence analysis along with docking simulation suggest that the unique binding site stereochemistry of PknG and PknD accommodates NU-6027 more favorably than other M. tuberculosis Ser/Thr protein kinases. Further, we also show that NU-6027 treatment induces the expression of proapoptotic genes in macrophages. Finally, we demonstrate that NU-6027 inhibits M. tuberculosis growth in both macrophage and mouse tissues. Taken together, these results indicate that NU-6027 can be optimized further for the development of antimycobacterial agents.

Oral Delivery of Cholic Acid-Derived Amphiphile Helps in Combating Salmonella-Mediated Gut Infection and Inflammation.

A major impediment to developing effective antimicrobials against Gram-negative bacteria like Salmonella is the ability of the bacteria to develop resistance against existing antibiotics and the inability of the antimicrobials to clear the intracellular bacteria residing in the gastrointestinal tract. As the critical balance of charge and hydrophobicity is required for effective membrane-targeting antimicrobials without causing any toxicity to mammalian cells, herein we report the synthesis and antibacterial properties of cholic acid-derived amphiphiles conjugated with alkyl chains of varied hydrophobicity. Relative to other hydrophobic counterparts, a compound with hexyl chain (6) acted as an effective antimicrobial against different Gram-negative bacteria. Apart from its ability to permeate the outer and inner membranes of bacteria; compound 6 can cross the cellular and lysosomal barriers of epithelial cells and macrophages and kill the facultative intracellular bacteria without disrupting the mammalian cell membranes. Oral delivery of compound 6 was able to clear the Salmonella-mediated gut infection and inflammation, and was able to combat persistent, stationary, and multi-drug-resistant clinical strains. Therefore, our study reveals the ability of cholic acid-derived amphiphiles to clear intracellular bacteria and Salmonella-mediated gut infection and inflammation.

An In Vitro Study of Bactericidal Effect of Gallium Aluminium Arsenide Laser on Anaerobic Photosensitized Periodontopathics.

AIM: To investigate the bactericidal effect of gallium aluminium arsenide (GaAlAs) laser on photosensitized predominant periodontopathogenic anaerobic organisms. MATERIALS AND METHODS: The present prospective study was carried out among 50 patients of chronic periodontitis with pockets ≥ 5 mm depth. For sample analysis of P. intermedia and P. gingivalis, a subgingival plaque was collected from periodontal pockets using sterile curettes under aseptic conditions. The sample was then immediately transported to microbiology laboratory using Transport media, Thioglycollate broth with Vitamin K and Hemin. After incubation period again the number of the viable bacterial count was carried out using a magnifying glass and expressed as CFU/mL, to determine the bactericidal effect of GaAlAs laser. A predetermined number of colonies (for P. intermedia 500 colonies were taken initially; for P. gingivalis 400 colonies were taken initially) were taken equally as control group and case group. The data was statistically analyzed using the SPSS statistical software version 16. Mann-Whitney Test was used for statistical analysis with p value less than 0.05 considered statically significant. RESULTS: Study group shows a reduction in colony count of P. intermedia after being exposed to GaAlAs diode laser for 1 minute from 369-229, 134 and 41 which was statistically significant with p value <0.0001. Study group shows a decrease in colony count of P. gingivalis after being exposed to GaAlAs diode laser for 1 minute from 286.52-197, 94 and 39 which was statistically significant with p value <0.0001. CONCLUSION: The result of our study implies that for all tested bacterial strains, the effect of GaAlAs laser for 1 minute resulted in a significant reduction in the viable counts of photosensitized predominant periodontopathogenic anaerobic organisms. Photodynamic therapy (PDT) kills the bacteria and also leads to the detoxification of endotoxins. Further, it can thus be safely concluded that this technique is an alternative method adjunct to mechanical therapy. CLINICAL SIGNIFICANCE: The application of an alternative method to eradicate bacteria from periodontal pockets is desirable. One such approach is photodynamic therapy (PDT), i.e., laser therapy. Owing to the emergence of antibiotic resistance, PDT has to turn out to be a feasible alternative antibacterial therapy for biofilm-related diseases.

Resistin and Plasma-reactive Oxygen Metabolite Levels in Obese and Non-obese Individuals with Chronic Periodontitis in Response to Non-surgical Periodontal Therapy.

AIM: To assess and compare the impact of non-surgical periodontal therapy on plasma reactive oxygen metabolites and resistin values in chronic periodontitis obese and non-obese patients. MATERIALS AND METHODS: Total 200 subjects were included in the present study and were broadly divided into two study groups with 100 patients in each group as follows: group A: Obese patients with chronic periodontitis, group B: Non-obese, normal weight patients with chronic periodontitis. Various following periodontal parameter were calculated at the baseline time and two months after the non-surgical periodontal therapy. Plasma reactive oxygen metabolite (RM) and serum and GCF resistin levelswere evaluated. Assessment of all the results was done by Statistical Package for Social Sciences (SPSS) software. RESULTS: Significant results were obtained while doing an inter-group comparison of clinical attachment levels between two study groups. Significant results were obtained while comparing the clinical attachment levels in both the study groups at different time intervals. Significant 9 reduction in the RM was seen in Group B subjects in comparison to Group A subjects 2 months after non-surgical periodontal therapy. CONCLUSION: In patients with chronic periodontitis, obesity can be considered as an important factor in the alteration of resistin levels. CLINICAL SIGNIFICANCE: Obese patients should be motivated for reducing weight so that periodontal therapy and other treatment modalities could be carried out more effectively.

Nonsurgical Periodontal Therapy decreases the Severity of Rheumatoid Arthritis: A Case-control Study.

INTRODUCTION: Rheumatoid arthritis (RA) and periodontitis are common chronic inflammatory conditions. Several studies suggested a relationship between RA and periodontitis. Recent studies have shown a beneficial effect of periodontal treatment on the severity of active RA. So the aim of this study was to examine the effect of nonsurgical periodontal therapy on the clinical parameters of RA. MATERIALS AND METHODS: A total of 60 subjects with moderate-to-severe chronic generalized periodontitis and active RA in the age range 18 to 65 were selected for the study. They were divided into two groups. Group A (control group) consisted of 30 subjects with chronic generalized periodontitis and RA, and group B of 30 subjects with chronic generalized peri-odontitis and RA and they received nonsurgical periodontal therapy (scaling, root planning, and oral hygiene instructions). Evaluation of clinical observations of Simplified Oral Hygiene Index (OHI-S), gingival index (GI), bleeding on probing (BOP), probing pocket depth (PPD), clinical attachment level (CAL), number of swollen joints (SJ), number of tender joints (TJ), values of erythrocyte sedimentation rate (ESR), visual analogue scale (VAS) for patient's global assessment, 3 months disease activity score (DAS) index, and C-reactive protein (CRP) was done at baseline and 3 months. Statistical evaluation of clinical observations was carried out. RESULTS: Group B subjects who received nonsurgical periodon-tal therapy showed statistically significant improvement in all periodontal and RA parameters at 3 months, compared with group A who did not receive periodontal therapy. CONCLUSION: It can be concluded from the result that nonsurgical periodontal therapy may contribute to reduction in severity and symptoms of RA. CLINICAL SIGNIFICANCE: Rheumatoid arthritis patients should be evaluated for periodontitis and treated for the same in order to reduce its severity level.

Evaluation of genetic diversity among aquatic and fecal isolates of Escherichia coli using multilocus variable number of tandem repeat analysis.

In developing countries like India, fecal pollution of surface waters is a major threat to public and environmental health. The aim of the study was to assess serological, phylogenetic and molecular diversity among aquatic Escherichia coli isolates from Yamuna river and their comparison with the animal fecal isolates. A total of 97 E. coli isolates from Yamuna river and domesticated animals were characterized by multilocus variable number tandem repeat analysis (MLVA) using four VNTR loci. The pathogenicity of these strains by serological and phylogenetic analysis was also determined. E. coli strains were differentiated into 53 distinct MLVA types with high discriminatory power, Simpson's index of 0.95 (95% CI 0.923-0.978). Cluster analysis and population modeling using minimum spanning tree suggested a possible epidemiological linkage among aquatic and fecal isolates. The study also reported the presence of highly diverse and pathogenic serotypes belonging to STEC and EPEC strains, particularly O157 and high prevalence of pathogenic phylogroups (phylogroup, B2 and D). The presence of such a high molecular heterogeneity among aquatic and fecal E. coli isolates emphasizes upon the need to develop proper fecal pollution abatement strategies for Indian natural bodies.

Hemangiopericytoma of meningo-fronto-naso-orbito-maxillary complex.

Hemangiopericytoma (HPC) is a rare vascular tumour and difficult to diagnose clinically. Incidence is reported in fourth to fifth decade of life.With female predominance, 3%-5% cases affect the oral cavity, sinus lining and meninges. The patient presented with 8×6 cm swelling on her face, evaluation reported it to be HPC. Bilateral maxillary artery embolisation, wide local excision of the lesion, preserving the left eye and its function, was done. No recurrence is reported at 1-year follow-up. Response of such lesions to radiotherapy is questionable; with no lymphadenopathy and adequate encapsulation, embolisation of feeder vessel followed by a wide local excision of the lesion seems to be a fairly good option of treatment.

Assessment of Level of Perceived Stress and Sources of Stress Among Dental Professionals Before and During the COVID -19 Outbreak.

CONTEXT: The recent spread of SARS-CoV-2 pandemic has resulted in a number of mental health issues among healthcare workers and dentists are no exception to this due to their nature of work. Hence, the aim of this study was to evaluate the level of perceived stress (PS) among Chhattisgarh dentists and identify the sources of stress before and during the COVID-19 crisis. MATERIALS AND METHODS: An online questionnaire-based survey was done to assess the level of PS using perceived stress scale (PSS) and sources of stress among dentists of Chhattisgarh state of India before the onset of COVID-19 in the state and immediately after the nationwide lockdown was announced owing to COVID-19 outbreak. Based on the type of work, the dental practitioners were categorized into three groups--dental practitioners (group A), dental academicians (group B), and dentists who are practitioners as well as academicians (group C). Frequency, percentages, and mean values were calculated and compared among different participant characteristics using Student's t test, paired t test, and one-way ANOVA. RESULTS: During phase I, mean PSS for dentists was 18.61 ± 6.87 which increased to 20.72 ± 1.95 in phase II. Group C dentists recorded higher mean PSS during phase I, while group A dentists reported higher mean PSS during phase II. No family time due to long working hours (90%) was the major stressor among the three groups of dentists during phase I and concern about getting infected (83.3%) was identified as the most frequent stressor during phase II followed by stress over financial implications. CONCLUSION: Chhattisgarh dentists are reeling under psychological stress, which could be highly deteriorating to their mental health. Hence, concerned authorities should come forward and support the dentists by providing adequate guidelines, policies, and monetary support to them.

High Prevalence of Antibiotic Resistance and Integrons in Escherichia coli Isolated from Urban River Water, India.

The contamination of surface waters with multidrug resistant (MDR) coliforms is a major public health concern in developing countries. This study was aimed to evaluate the occurrence of antibiotic resistance and role of integrons in the spread of resistance genes in Escherichia coli isolated from urban waters of river Yamuna. One hundred and forty-one strains of E. coli were isolated and assessed for antibiotic resistance wherein high resistance was observed for Cefazolin. Integrons (class 1 and class 2) were detected in 32% of the isolates. Variable region of class 1 integron carried different gene cassettes, namely. dfrA17-aadA5, dfrA12-orfF-aadA2, blaOXA-1-aadA1, and unusual phage tail tape measure protein. These integron-positive isolates were further characterized by phylogrouping, serotyping, and BOX-PCR typing. Phylogroup B2 was found to be the most prevalent. Pathogenic E. coli O157 was also reported. Majority of the isolates (54%; 7/13) carrying "dfrA17-aadA5" gene cassette were clustered predominantly into a single BOX-PCR type (B8), suggesting a genetic relatedness among the isolates. This study thus depicts very high incidence of multidrug resistance and class 1 integrons in surface water of India. The prevalence of integrons in aquatic E. coli correlated well with resistance to increasing number of antibiotic classes and multiple antibiotic resistance (MAR) index at various sites. Integron-positive MDR E. coli isolates were found to be serologically and genetically diverse suggesting major role of integrons in the emergence and dissemination of resistance traits in waterborne E. coli.