Exploring two contrasting surface‐active exopolysaccharides from a single strain of Ochrobactrum utilizing different hydrocarbon substrates

During production and characterization of exopolysaccharides (EPS) of Ochrobactrum pseudintermedium C1, it was observed that an experimental change in the basic hydrocarbon type of substrate for bacterial utilization led to elicitation of different surface‐active properties in the EPS produced. In the sugar substrate, it elicited surfactant property, while in oil substrates it elicited emulsifying property, which indicated that the EPS might be different. Consequently, attention was focused on a detailed analysis of this substrate‐specific EPS. Utilizing waste sugar, edible, and mineral oil substrates, EPS produced in each situation was characterized. Besides estimating surface activity and thermostability, each substrate‐specific EPS was analyzed by Fourier‐transform infrared spectroscopy, gas chromatography‐mass spectroscopy, ¹H‐nuclear magnetic resonance, and matrix‐assisted laser desorption/ionization—time of flight mass spectroscopy to find any structural difference. The results were significantly contrasting although the similarity in molecular mass suggested a basic similarity in polysaccharide structure. Morphological differences were also evident both macroscopically and microscopically with scanning electron microscopy. As the surface‐active property of EPS was dependent on the substrate utilized, their structural differences might account for it. These diverse surface activities of EPS produced by a single bacterial strain simply by changing the nature of substrate would also augment their bioapplications. Moreover, utilization of waste and easily available substrates should make such applications convenient, ecofriendly, and cost‐worthy.     

Magnetic,structural and magnetocaloric properties of Ni-Si and Ni-Al thermoseeds for self-controlled hyperthermia

Self-controlled hyperthermia is a non-invasive technique used to kill or destroy cancer cells while preserving normal surrounding tissues. We have explored bulk magnetic Ni-Si and Ni-Al alloys as a potential thermoseeds. The structural, magnetic and magnetocaloric properties of the samples were investigated, including saturation magnetisation, Curie temperature (T_C), and magnetic and thermal hysteresis, using room temperature X-ray diffraction and magnetometry. The annealing time, temperature and the effects of homogenising the thermoseeds were studied to determine the functional hyperthermia applications. The bulk Ni-Si and Ni-Al binary alloys have Curie temperatures in the desired range, 316?K–319?K (43?°C–46?°C), which is suitable for magnetic hyperthermia applications. We have found that T_C strictly follows a linear trend with doping concentration over a wide range of temperature. The magnetic ordering temperature and the magnetic properties can be controlled through substitution in these binary alloys.     

Intensive Phase Non-Compliance to Anti Tubercular Treatment in Patients with HIV-TB Coinfection: A Hospital-based Cross-Sectional Study

We aimed to study the prevalence and determinants of non compliance to intensive phase anti tubercular treatment (ATT) in 111 HIV-TB coinfection patients, attending the APEX Referral Center for HIV/AIDS at Medical College, Kolkata with a specially-designed, semi-structured, pre-tested questionnaire. Compliance was defined as taking ≥95% of the total scheduled doses of anti-TB medicines during the intensive phase. Data was collected on socio-demographic parameters, disease information, patient’s knowledge and barriers to treatment. The prevalence of non-compliance to ATT in HIV-TB coinfection patients was found to be 40.5% (95% C.I. = 30.5, 50.5). Multivariate logistic regression analysis showed that absence of proper counseling, lack of knowledge about correct route of TB transmission, visiting quacks during ATT and the urge to leave treatment once patient started feeling better were the significant determinants of non-compliance. “No Counseling” increased chances of non- compliance (adjusted O.R.) 47.12 times (95% C.I. = 7.99, 195.27); thereby being the single most influential variable towards the outcome. The present study finds an alarmingly high prevalence of non-compliance to ATT among HIV-TB coinfection patients. The results clearly indicate that adequate counseling about this coinfection and the importance of compliance, along with better patient-friendly orientation of DOTS programme is urgently needed. Collaborative TB-HIV activities are essential to ensure better ATT compliance in coinfection patients.