Seroprevalence pattern among blood donors in a tertiary health care center

Although blood transfusion is a life-saving maneuver, it is associated with certain risks. In general, transfusion-related adverse events are categorized as infectious and noninfectious. Transfusion-transmissible infectious agents such as human immunodeficiency virus (HIV), hepatitis B virus (HBV), hepatitis C virus (HCV) and syphilis are among the greatest threats to blood safety for the recipient. To assess the magnitude and dynamics of disease transmission and for its prevention and control, the study of its seroprevalence is important. Our institute, catering to the needs of a large population in the foothills of the Himalayas, represents an important center for serological surveys. This study aimed to determine the seroprevalence of HIV, HBV, HCV and syphilis infections among blood donors in a tertiary care center of this region. A retrospective analysis of medical records of blood donors who met the standard criteria for donor fitness were screened for HIV, HBS, HCV, Syphilis and Malaria, from January 2007 to December 2011 (5 years). Out of 7884 units collected, 83 (1.05%) units had seropositivity for HBsAg/anti-HCV Ab/anti-HIV Ab/anti-Treponemal Ab, 2 units each revealed dual infections with HIV-HBV and HIV-HCV. Seropositivity rates of HBsAg, anti-HCV Ab, anti-HIV Ab and anti-treponemal Ab were 0.63%, 0.20%, 0.19% and 0.02%, respectively. Even with the implementation of effective preventive strategies, there is significant risk of transmission of infectious agents in India. Efforts to ensure an adequate and safe blood supply should include proper screening and striving for optimal use of blood and its products.Keywords: Seroprevalence; HIV; Hepatitis B; Hepatitis C; Syphilis; Uttarakhan

Does a surface attached globule phase exist ?

A long flexible neutral polymer chain immersed in a poor solvent and interacting with an impenetrable attractive surface exhibits a phase known as surface attached globule ({\bf SAG}) in addition to other adsorbed and desorbed phases. In the thermodynamic limit, the {\bf SAG} phase has the same free energy per monomer as the globular phase, and the transition between them is a surface transition. We have investigated the phase diagrams of such a chain in both two- and three- dimensions and calculated the distribution of monomers in different domains of the phase diagram.Comment: 7 pages, 7 postscript figure

Force-induced desorption of a linear polymer chain adsorbed on an attractive surface

We consider a model of self-avoiding walk on a lattice with on-site repulsion and an attraction for every vertex of the walk visited on the surface to study force-induced desorption of a linear polymer chain adsorbed on an attractive surface and use the exact enumeration technique for analyzing how the critical force for desorption $f_c(T)$ depends on the temperature. The curve $f_c(T)$ gives the boundary separating the adsorbed phase from the desorbed phase. Our results show that in two dimensions where surface is a line the force $f_c(T)$ increases monotonically as temperature is lowered and becomes almost constant at very low temperatures. In case of three-dimensions we, however, find re-entrance, i. e. $f_c(T)$ goes through a maximum as temperature is lowered. The behaviour of the polymer chain at different values of temperature and force is examined by calculating the probability distribution of the height from the surface of the vertex at which external force is applied.Comment: Preprint 15 pages with 8figures and two tables. The file table-2d.ps and table-3d.ps lists C_N(Ns,h) for given N with all possible Ns and h in two and three dimension

Role of loop entropy in the force induced melting of DNA hairpin

Dynamics of a single stranded DNA, which can form a hairpin have been studied in the constant force ensemble. Using Langevin dynamics simulations, we obtained the force-temperature diagram, which differs from the theoretical prediction based on the lattice model. Probability analysis of the extreme bases of the stem revealed that at high temperature, the hairpin to coil transition is entropy dominated and the loop contributes significantly in its opening. However, at low temperature, the transition is force driven and the hairpin opens from the stem side. It is shown that the elastic energy plays a crucial role at high force. As a result, the phase diagram differs significantly with the theoretical prediction.Comment: 9 pages, 8 figures; J. Chem. Phys (2011

Radiological diagnosis of Cysticercosis of Breast - An unusual presentation

Breast cysticercosis manifestation is usually uncommon and only a few cases have been reported in the literature. Thismanifests in the form of signs and symptoms which normally do not point towards the diagnosis. The radiological modalitiesalways narrow down the gap between the complaints and the diagnosis. We present a case with cysticercus cysts in breastparenchyma as well as in both pectoral muscles which was suspected on ultrasonography (USG) and diagnosed on MagneticResonance Imaging (MRI). The patient responded to the medical treatment conservatively thus avoiding excisional biopsy.Follow up and repeat MRI has confirmed the cure of the complaints as well as the disease

COMPARISION OF LOCAL ANAESTHETIC POTENTIALS OF DRUGS HAVING MEMBRANE STABILIZING EFFECT ON INFILTRATION ANAESTHESIA IN GUINEA PIGS

Objective : To compare the local anaesthetic action of central neuron sodium channel blockers Phenytoin Sodium, Sodium Valproate and Carbamazepine with peripheral neuron sodium channel blockers Lignocaine using Infiltration anaesthesia in guinea pigs Material and Methods: In the present study,the local anaesthetic effect of Lignocaine with concentration of 0.2%, 0.1% ,0.05% was compared with Phenytoin Sodium, Sodium Valproate and Carbamazepine in concentrations of 0.2%, 0.1% ,0.05% using different dilutions of  0.05N,0.1N,0.2N HCL  in guinea pig by pricking on the skin produces a squeak or  movement  indicating pain is produced. Results : The results of our present study suggest onset of local anaesthesia with lignocaine 0.2% is significantly fast when compared with concentration of 0.1%, and 0.05% indicating it has better efficacy  when  using for various   local anaesthetic  procedures. In addition onset of local anaesthesia with Phenytoin sodium concentrations of 0.2%, 0.1% ,0.05%  is fast  when compared with Sodium valproate concentrations of 0.2%, 0.1% ,0.05%  and  Carbamazepine concentrations 0.2%, 0.1% ,0.05%. Conclusion: Among antiepileptic drugs with local anaesthesia and  membrane stabilizing activity Phenytoin sodium showed fast on set of action when compared with sodium valproate and Carbamazepine indicating it has better efficacy. Keywords : Local Anaesthetics, Membrane Stabilizing, Infiltration anaesthesia

Indian Ocean marine biogeochemical variability and its feedback on simulated South Asia climate

We investigate the effect of variable marine biogeochemical light absorption on Indian Ocean sea surface temperature (SST) and how this affects the South Asian climate. In twin experiments with a regional Earth system model, we found that the average SST is lower over most of the domain when variable marine biogeochemical light absorption is taken into account, compared to the reference experiment with a constant light attenuation coefficient equal to 0.06 m−1. The most significant deviations (more than 1 ∘C) in SST are observed in the monsoon season. A considerable cooling of subsurface layers occurs, and the thermocline shifts upward in the experiment with the activated biogeochemical impact. Also, the phytoplankton primary production becomes higher, especially during periods of winter and summer phytoplankton blooms. The effect of altered SST variability on climate was investigated by coupling the ocean models to a regional atmosphere model. We find the largest effects on the amount of precipitation, particularly during the monsoon season. In the Arabian Sea, the reduction of the transport of humidity across the Equator leads to a reduction of the large-scale precipitation in the eastern part of the basin, reinforcing the reduction of the convective precipitation. In the Bay of Bengal, it increases the large-scale precipitation, countering convective precipitation decline. Thus, the key impacts of including the full biogeochemical coupling with corresponding light attenuation, which in turn depends on variable chlorophyll a concentration, include the enhanced phytoplankton primary production, a shallower thermocline, and decreased SST and water temperature in subsurface layers, with cascading effects upon the model ocean physics which further translates into altered atmosphere dynamics

Pulling absorbing and collapsing polymers from a surface

A self-interacting polymer with one end attached to a sticky surface has been studied by means of a flat-histogram stochastic growth algorithm known as FlatPERM. We examined the four-dimensional parameter space of the number of monomers up to 91, self-attraction, surface attraction and force applied to an end of the polymer. Using this powerful algorithm the \emph{complete} parameter space of interactions and force has been considered. Recently it has been conjectured that a hierarchy of states appears at low temperature/poor solvent conditions where a polymer exists in a finite number of layers close to a surface. We find re-entrant behaviour from a stretched phase into these layering phases when an appropriate force is applied to the polymer. We also find that, contrary to what may be expected, the polymer desorbs from the surface when a sufficiently strong critical force is applied and does \emph{not} transcend through either a series of de-layering transitions or monomer-by-monomer transitions.Comment: 4 pages, 4 figure