Water-soluble vitamin-E for enhancing fluorescence diagnosis in infected human dentine treated with NaOCl.

INTRODUCTION: Bacterial fluorescence methods are of interest in endodontics for informing endpoints for debridement. This study explored potential fluorescence quenching reversal effects of a water-soluble vitamin E conjugate (d-α-Tocopherol polyethylene glycol 1000 succinate, TPGS) when applied to polymicrobial biofilms grown on dentine that had been exposed to sodium hypochlorite (NaOCl) to cause quenching. METHOD: Extracted human teeth were debrided, embedded in transparent acrylic resin and sectioned. After smear layer removal, tooth dentine sections were inoculated with a polymicrobial inoculum, and cultured for 7 days to create biofilms. Samples (n = 8 per group) were exposed to 1 % or 4 % NaOCl for 2 or 4 min, and then treated with TPGS. Bacterial fluorescence readings under laser excitation at 655 nm were assessed over 10 min using a calibrated DIAGNOdent device. All data were assessed for normality (Kolmogorov-Smirnov test) and analysed with ANOVA followed by Bonferroni post-hoc tests. RESULTS: NaOCl at both concentrations quenched fluorescence readings of biofilms grown on dentine samples, with a maximal reduction of 40.4 % at 5 min after 4 % NaOCl. Treatment with TPGS gave faster recovery of fluorescence readings compared to the control at 5 and 10 min. CONCLUSION: The water-soluble antioxidant TPGS partially reversed fluorescence quenching caused by NaOCl. This agent may have value clinically for reducing the time needed for fluorescence readings to recover when NaOCl is used as an irrigant. This will facilitate more accurate assessment of endpoints for canal debridement.

The effects of keratin-coated titanium on osteoblast function and bone regeneration.

Wool derived keratin, due to its demonstrated ability to promote bone formation, has been suggested as a potential bioactive material for implant surfaces. The aim of this study was to assess the effects of keratin-coated titanium on osteoblast functionin vitroand bone healingin vivo. Keratin-coated titanium surfaces were fabricated via solvent casting and molecular grafting. The effect of these surfaces on the attachment, osteogenic gene, and osteogenic protein expression of MG-63 osteoblast-like cells were quantifiedin vitro. The effect of these keratin-modified surfaces on bone healing over three weeks using an intraosseous calvaria defect was assessed in rodents. Keratin coating did not affect MG-63 proliferation or viability, but enhanced osteopontin, osteocalcin and bone morphogenetic expressionin vitro. Histological analysis of recovered calvaria specimens showed osseous defects covered with keratin-coated titanium had a higher percentage of new bone area two weeks after implantation compared to that in defects covered with titanium alone. The keratin-coated surfaces were biocompatible and stimulated osteogenic expression in adherent MG-63 osteoblasts. Furthermore, a pilot preclinical study in rodents suggested keratin may stimulate earlier intraosseous calvaria bone healing.

Risk factors of tuberculosis in human and its association with cattle TB in Nepal: A one health approach.

Tuberculosis (TB) in humans is primarily caused by Mycobacterium tuberculosis (M. tuberculosis), with millions of infections and hundreds of thousands of deaths worldwide. It creates a substantial economic burden on the community. Unlike M. tuberculosis, Mycobacterium bovis infects cattle and causes bovine TB, also known as zoonotic TB. People can contract zoonotic TB after consumption of unpasteurized dairy products, handling the sick animals, and via occupational exposures. The association between the zoonotic TB in humans and cattle is not well known in Nepal. The study examined the associated risk factors, including exposure to infected cattle, that contribute to TB's development in human beings in Nepal. The study consists of human and animal subjects. Firstly, a retrospective matched case-control study was conducted at the National Tuberculosis Center (NTC), Bhaktapur, Nepal. A total of 290 people (equal numbers of TB cases and control subjects) were interviewed to obtain information on socio-demographic, behavioral, and occupational risks, including the history of cattle related exposures. Secondly, a cross-sectional study was performed among the cattle owned by the TB-confirmed patients. Comparative tuberculin skin test, rapid antibody test, and ELISA were used in parallel to detect M. bovis infection in cattle. The risk factors for the development of TB in humans were smokers (OR = 4.6, 95% CI: 2.1-10.0, p < 0.001), previous history of TB (OR = 7.9, 95% CI: 3.0-20.6, p < 0.001) and history of cattle exposures (OR = 3.9, 95% CI: 2.1-7.4, p = 0.001). Out of 123 cattle sampled, 12 cattle (9.76%, 95% CI: 5.37-16.76, p < 0.0001) were positive by the tuberculin test, 46 (37.4%, 95% CI: 28.97-46.62, p = 0.007) were tested positive by the rapid test, and 7 (5.7%, 95% CI: 2.52-11.80, p < 0.0001) by ELISA test. The inter-test agreement between the tuberculin and ELISA was very strong (κ = 0.72, 95% CI: 0.48-0.95, p < 0.01). This study indicates that exposure to infected cattle and socio-demographic risk factors can contribute to the development of TB in human beings.

Prevalence of Bacterial Vaginosis and Its Association with Risk Factors among Nonpregnant Women: A Hospital Based Study.

Bacterial vaginosis (BV) is an ecological imbalance of the vaginal microbiota affecting mostly women of reproductive age group. This study was carried out among 160 nonpregnant women registered at the Outpatient Department of Gynaecology/Obstetrics of KIST Medical College Teaching Hospital, Imadol, Lalitpur, Nepal, from November 2014 to May 2015. The aim of the study was to assess the association of the risk factors with BV and analyze the type of bacteria associated with BV. Nugent's scoring method was used for diagnosis of BV in this study. The overall prevalence of BV was 24.4% among symptomatic patients. Douching was statistically related to BV (P = 0.015). Also, BV was significantly associated with consistency (P = 0.0001), odor (P = 0.02), and amount of abnormal vaginal discharge (P = 0.09). Contraceptives users on anatomical sites were found more prone to BV than those who did not use contraceptives on anatomical sites. Pseudomonas spp., Escherichia coli, Acinetobacter spp., Proteus spp., Klebsiella spp., Neisseria gonorrhoeae, Enterobacter spp., Citrobacter spp., Staphylococcus aureus, Coagulase-Negative Staphylococci (CoNS), and Streptococcus agalactiae were associated with BV and out of those Lactobacillus spp. was the predominant organism. The higher prevalence of BV among symptomatic patients indicates interventions should be applied to reduce the incidence of stillbirth, abortion, and sterility.