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In this study, a biological evaluation of the antimicrobial activity of Zn-doped titania nanofibers was carried out using Escherichia coli ATCC 52922 (Gram negative) and Staphylococcus aureus ATCC 29231 (Gram positive) as model organisms. The utilized Zn-doped titania nanofibers were prepared by the electrospinning of a sol-gel composed of zinc nitrate, titanium isopropoxide, and polyvinyl acetate; the obtained electrospun nanofibers were vacuum dried at 80°C and then calcined at 600°C. The physicochemical properties of the synthesized nanofibers were determined by X-ray diffraction pattern, field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, electron probe microanalysis, thermogravimetry, and transmission electron microscopy (TEM). The antibacterial activity and the acting mechanism of Zn-doped titania nanofibers against bacteria were investigated by calculation of minimum inhibitory concentration and analyzing the morphology of the bacterial cells following the treatment with nanofibers solution. Our investigations reveal that the lowest concentration of Zn-doped titania nanofibers solution inhibiting the growth of S. aureus ATCC 29231 and E. coli ATCC 52922 strains is found to be 0.4 and 1.6 μg/ml, respectively. Furthermore, Bio-TEM analysis demonstrated that the exposure of the selected microbial strains to the nanofibers led to disruption of the cell membranes and leakage of the cytoplasm. In conclusion, the combined results suggested doping promotes antimicrobial effect; synthesized nanofibers possess a very large surface-to-volume ratio and may damage the structure of the bacterial cell membrane, as well as depress the activity of the membranous enzymes which cause bacteria to die in due course.

We explored electrospinning as a feasible and practicable mode for encapsulation and stabilization of Lactobacillus gasseri. The utilized nanocomposite was prepared using sol-gel composed of animate L. gasseri and inanimate PVA. The objective was to examine the ability of electrospinning method to protect functional properties of probiotic L. gasseri. The PVA was used as an encapsulation matrix as it is biocompatible and hydrophilic in nature thus facilitate an easy revival of bacteria. The characterization of as-spun bioproduct was done by energy-dispersive X-ray spectrometer, SEM, and TEM, whereas thermal behavior was analyzed by thermogravimetry. The viability was confirmed by traditional pour plate method and fluorescence microscopy. Furthermore, to test whether the functionality of L. gasseri was affected, the encapsulated L. gasseri were fed to mouse for colonization. Our results pointed out that encapsulated bacteria were viable for months, and their metabolism was not affected by immobilization; thus, they could be used in food engineering and trade.

Of the total 125 subjects enrolled in our present study, 25 cases were of PCa and 100 were healthy controls. The mean value of fasting plasma glucose was 95.5 mg/dl in cases of prostatic carcinoma and the mean value of fasting plasma insulin was 5.78 µU/ml (p value: 0.0001*). The fasting insulin levels µU/ml were categorized into the different ranges starting from ≤2.75, >2.75 to ≤4.10, >4.10 to ≤6.10, >6.10µU/ml. The maximum number of cases of prostatic carcinoma of fasting insulin levels falls in range of >6.10µU/ml. The highest insulin levels (>6.10µU/ml) were seen to be associated with an 2.55 fold risk of prostatic carcinoma when compared with fasting insulin levels of (<2.75 µU/ml). Conclusions: Elevated fasting levels of serum insulin appear to be associated with a higher risk of prostate cancer.

Background: Breast cancer is the second most common malignancy among Nepalese women, accounting for 60% of the total cancer cases in females. Women diagnosed with germline mutations in BRCA1 like 185delAG, 1294del40 develop breast and/or ovarian cancer with a lifelong likelihood of up to 85% whereas presence of a mutation increases the risk for mutations to occur in other genes. The major objective of this study was to find the prevalence of these mutations in Nepalese cancer patients. Materials and Methods: This prospective study was carried out at two cancer hospitals in the Kathmandu valley over a period of 11 months. Irrespective of age group and stage of canceran appropriate amount of blood was withdrawn from 50 breast cancer patients and 20 controls. DNA was extracted manually and subjected to PCR using primers for 185delAG and 1294del40 mutations. PCR products were then digested with restriction enzyme (DdeII) followed by electrophoresis. Results: Prevalence of 185delAG in reference breast cancer patients was found to be 4/50 (8%) but no 1294del40 was apparent. Conclusions: Several mutations occurring in different exons of BRCA1 as well as mutations in other genes like BRCA2, for example, should also be taken in account.

Mn₂O₃ nanowires with diameter ~70 nm were synthesized by a simple hydrothermal method using Mn(II) nitrate as precursor. X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy (TEM), and energy dispersive X-ray spectroscopy techniques were employed to study structural features and chemical composition of the synthesized nanowires. A biological evaluation of the antimicrobial activity and cytotoxicity of Mn₂O₃ nanowires was carried out using Escherichia coli and mouse myoblast C₂C₁₂ cells as model organism and cell lines, respectively. The antibacterial activity and the acting mechanism of Mn₂O₃ nanowires were investigated by using growth inhibition studies and analyzing the morphology of the bacterial cells following the treatment with nanowires. These results suggest that the pH is critical factor affecting the morphology and production of the Mn₂O₃ nanowires. Method developed in the present study provided optimum production of Mn₂O₃ nanowires at pH ~ 9. The Mn₂O₃ nanowires showed significant antibacterial activity against the E. coli strain, and the lowest concentration of Mn₂O₃ nanowires solution inhibiting the growth of E. coli was found to be 12.5 μg/ml. TEM analysis demonstrated that the exposure of the selected microbial strains to the nanowires led to disruption of the cell membranes and leakage of the internal contents. Furthermore, the cytotoxicity results showed that the inhibition of C₂C₁₂ increases with the increase in concentration of Mn₂O₃ nanowires. Our results for the first time highlight the cytotoxic and bactericidal potential of Mn₂O₃ nanowires which can be utilized for various biomedical applications.