B CHROMOSOMES IN ANGIOSPERM--A REVIEW

A review article on B chromosomes (Bs) in angiosperms is documented considering occurrence, morphology, polymorphic B forms, divisional phase heterogeneity, chromatin organization and gene content, sequence composition, origin, evolutionary aspects and significant role on host with an objective to foresee the evolutionary perspectives as it still remains an enigma. Irrespective of the origin of Bs, it seems that they have attained the following modifications, namely, insertion of centromeric and telomeric sequences, structural reorganization and procuring mitotic and meiotic drives but shows genetic inertness and present in the host as selfish DNA. In the context, few questions are raised. Further, scientific quest may unravel the unexplored information about Bs to ascertain its evolutionary perspectives, if any.

Enhanced UV detection by transparent graphene oxide/ZnO composite thin films

Highly transparent graphene oxide–ZnO composite films synthesized by simple chemical method inhibit electron–hole recombination, modulate carrier transport and enhance UV detection capability.

Intercentrosomal angular separation during mitosis plays a crucial role for maintaining spindle stability

Cell division through proper spindle formation is one of the key puzzles in cell biology. In most mammalian cells, chromosomes spontaneously arrange to achieve a stable bipolar spindle during metaphase which eventually ensures proper segregation of the DNA into the daughter cells. In this paper, we present a robust three-dimensional mechanistic model to investigate the formation and maintenance of a bipolar mitotic spindle in mammalian cells under different physiological constraints. Using realistic parameters, we test spindle viability by measuring the spindle length and studying the chromosomal configuration. The model strikingly predicts a feature of the spindle instability arising from the insufficient intercentrosomal angular separation and impaired sliding of the interpolar microtubules. In addition, our model successfully reproduces chromosomal patterns observed in mammalian cells, when activity of different motor proteins is perturbed.

Biomedical waste management: study on the awareness and practice among healthcare workers in a tertiary teaching hospital

Bio-medical waste has a higher potential of infection and injury to the healthcare worker, patient and the surrounding community. Awareness programmes on their proper handling and management to healthcare workers can prevent the spread of infectious diseases and epidemics. This study was conducted in a tertiary care hospital to assess the impact of training, audits and education/implementations from 2009 to 2012 on awareness and practice of biomedical waste segregation. Our study reveals focused training, strict supervision, daily surveillance, audits inspections, involvement of hospital administrators and regular appraisals are essential to optimise the segregation of biomedical waste.

Transient facial nerve paralysis (Bell's palsy) following administration of hepatitis B recombinant vaccine: a case report

Bell's palsy is the sudden onset of unilateral transient paralysis of facial muscles resulting from dysfunction of the seventh cranial nerve. Presented here is a 26-year-old female patient with right lower motor neurone facial palsy following hepatitis B vaccination. Readers' attention is drawn to an uncommon cause of Bell's palsy, as a possible rare complication of hepatitis B vaccination, and steps taken to manage such a presentation.

Tug-of-war between opposing molecular motors explains chromosomal oscillation during mitosis

Chromosomes move towards and away from the centrosomes during the mitosis. This oscillation is observed when the kinetochore, a specific protein structure on the chromosome is captured by centrosome-nucleated polymer called microtubules. We present a computational model, incorporating activities of various molecular motors and microtubule dynamics, to demonstrate the observed oscillation. The model is robust and is not restricted to any particular cell type. Quantifying the average velocity, amplitude and periodicity of the chromosomal oscillation, we compare numerical results with the available experimental data. Our analysis supports a tug-of-war like mechanism between opposing motors that changes the course of chromosomal oscillation. It turns out that, various modes of oscillation can be fully understood by assembling the dynamics of molecular motors. Near the stall regime, when opposing motors are engaged in a tug-of-war, sufficiently large kinetochore-microtubule generated force may prolong the stall durations.

Open safety pin in the nasal cavity

Foreign bodies in the nasal cavity are common-day occurrences in Otolaryngologic practice. But an open safety pin in nose with it' s sharp end directed towards roof is a rare incidence, and available literature is silent about this presentation; it is probably, the first of it' s kind being reported. Two cases of safety pins inside the nasal cavity, one open and the other closed, have been presented here with a brief review of literature.

Human lung carcinoma cells engineered to release IL2, IL7, GM-CSF and TNF alpha

A human lung adenocarcinoma cell line (LC89) was transduced with the IL2, IL7, GM-CSF and TNF alpha genes by retroviral vector mediated infection. This induced the constitutive and stable release of all cytokines. No difference or modulation was found in the parental and gene transduced LC89 cells with regard to cytokine receptor expression, in vitro cell growth and proliferation, nor in cell surface expression of different adhesion molecules. Following injection into immunosuppressed nu/nu mice, IL2 gene transduced LC89 cells lost their tumorigenic potential. LC89 cells engineered to release IL7 and TNF alpha grew in nu/nu mice, but in 40% of the animals tumor regression was observed. GM-CSF gene transduced LC89 cells showed a tumorigenic capacity identical to that of the parental clone. The levels of TGF beta(1) released by IL2, IL7 and GM-CSF gene transduced LC89 cells were markedly reduced compared to those of the parental and TNF alpha gene transduced cells. The results of this study support the concept that human lung cancer cells engineered with different cytokine genes maintain their intrinsic morphologic and proliferative features, while their tumorigenic and immunosuppressive capacities can be profoundly down-modulated. Both these effects are optimally achieved following insertion of the IL2 gene, suggesting that vaccination protocols with IL2 gene transduced tumor cells may be considered for the management of human lung cancer.

Minocycline treatment for HIV-associated cognitive impairment: results from a randomized trial

OBJECTIVE

We conducted a study of minocycline to assess its safety, tolerability, and efficacy for the treatment of HIV-associated cognitive impairment.

METHODS

HIV-1-infected individuals with progressive neurocognitive decline were enrolled in a double-blind, placebo-controlled study of minocycline. Participants were randomized to receive minocycline 100 mg or matching placebo orally every 12 hours. The primary efficacy measure was change in a neuropsychological test composite z score (NPZ-8) from baseline to week 24. Measures of safety included the frequency of adverse events and changes over time in laboratory tests. After 50% of participants completed the double-blind phase, an interim analysis of futility for the primary outcome measure was performed, and our Data and Safety Monitoring Board recommended early study termination.

RESULTS

A total of 107 HIV-1-infected individuals with cognitive impairment were enrolled. The minocycline group did not show improvement in the primary outcome measure (NPZ-8) (mean 24-week change = 0.12) compared to placebo (mean 24-week change = 0.17) (95% confidence interval = [-0.26, 0.39], p = 0.70). There were few severe adverse events or laboratory abnormalities in either treatment group.

CONCLUSION

Minocycline was safe and well-tolerated in individuals with HIV-associated cognitive impairment, but cognitive improvement was not observed. Classification of evidence. This interventional study provides Class II evidence for the safety, tolerability, and efficacy of minocycline for the treatment of HIV-associated cognitive impairment.

Dyselectrolytemia in chronic obstructive pulmonary diseases with acute exacerbation

Chronic Obstructive Pulmonary Disease (COPD) is one of the leading causes of mortality and morbidity world wide. Due to lack of awareness about the precipitating factors and predictors of prognosis, cases of acute exacerbation of COPD often suffer the fatal outcomes. In our study we assessed the levels of serum sodium and potassium in subjects with acute episodes of COPD and their healthy controls. We found a significantly low level of serum sodium (133± 6.86 meq/lit) and potassium (3.39 ± 0.96 meq/L)) in subjects with acute exacerbation of COPD than their healthy counterparts [sodium-142 ± 2.28 meq/L and potassium- 4.52 ± 0.02 meq/L (p <0.05)]. Therefore, our study findings suggest that, serum sodium and potassium levels may get deranged in subjects with acute exacerbations of COPD which should be routinely checked for to avoid fatal outcomes.

Meta-analysis of the effects of lithium usage on serum creatinine levels

There is conflicting evidence concerning lithium's effect on renal function. The aim is to clarify whether lithium affects kidney function and at what stage of treatment any effect may occur. Systematic review identified 23 studies split into three groups on which meta-analysis was performed to identify the following: A) lithium's effect on renal function in cross-sectional case-control studies, B) studies of renal function before and after commencement on lithium, C) studies of longer term effect in those already established on lithium therapy. Group A showed a statistically significant increase of 5.7 μmol/L in creatinine in the study population compared with controls. Group B showed a non-statistically significant rise in creatinine (2.9 μmol/L) after a mean follow-up of 86 months. Group C showed a statistically significant increase in creatinine of 7.0 μmol/L over a mean duration of 64 months. An increase in creatinine of an average of 1.6 μmol/L/year on lithium was also identified in this group. Any lithium-associated increase in serum creatinine is quantitatively small and of questionable clinical significance. However, routine renal function monitoring of patients on lithium is essential.

Dual-frequency dielectrophoretic levitation of Canola protoplasts

A novel dual-frequency excitation technique is introduced which permits investigation of the low-frequency dispersion of Canola plant protoplasts using feedback-controlled dielectrophoretic levitation. The upper and intermediate frequency spectra obtained using the new technique are generally consistent with previous work. However, below some cross-over frequency f(OL), the protoplasts exhibit an apparent positive dielectrophoretic response that is not predicted by conventional theory. This cross-over frequency is linearly related to suspension conductivity, virtually independent of the suspension pH, and inversely proportional to the square of the cell radius. Examination of the complex Clausius-Mossotti polarization coefficient reveals that the observed positive dielectrophoretic response can not be accounted for in terms of Maxwell-Wagner polarization associated with a conventional layered model for the protoplast. The failure of straightforward enhancements to the protoplast model in explaining the low frequency behavior may indicate the presence of an electrophoretic contribution to the net observable force on the particle. To account for such fluid mechanical effects, it will be necessary to modify the existing dielectrophoretic force formulation.