Background:Children suffering from beta-thalassemia major require repeated blood transfusions which may be associated with dangers like iron overload and contraction of infections such as HIV, HCV, and HBsAg which ultimately curtail their life span. On the other hand, inadequate transfusions lead to severe anemia and general fatigue and debility.Materials and Methods:Data were obtained from 142 beta-thalassemia major patients aged 3 years or more receiving regular blood transfusions at a transfusion centre in Western India from 1 April 2009 to 30 June 2009. The clinical data and laboratory results were subsequently analyzed.Results:Of the 142 patients, 76 (53.5%) were undertransfused (mean Hb <10 gm%). 96 (67%) of the patients were taking some form of chelation therapy but out of them only 2 (2%) were adequately chelated (S. ferritin <1000 ng/ml). 5 (3.5%) of the patients were known diabetics on insulin therapy. 103 (72%) of the patients were retarded in terms of growth. The prevalence of transfusion-transmitted infections (TTIs) such as HCV, HIV, and HBsAg was respectively 45%, 2%, and 2%, with the prevalence of HCV being significantly more than the general population. The HCV prevalence showed positive correlation with the age of the patients and with the total no of blood transfusions received. As many as 15% (6 out of 40) children who were born on or after 2002 were HCV positive despite the blood they received being subjected to screening for HCV.Conclusions:The study suggests the need to step up the transfusions to achieve hemoglobin goal of 10 gm% (as per the moderate transfusion regimen) and also to institute urgent and effective chelation measures with the aim of keeping serum ferritin levels below 1000 ng/ml to avoid the systemic effects of iron overload. In addition, strict monitoring of the children for endocrinopathy and other systemic effects of iron overload should be done. Rigid implementation of quality control measures for the ELISA kits used to detect HCV in donor blood needs to be done urgently. Alternately, more sensitive and specific measures (like NAT testing) should be employed for detection of HCV. In the absence of a definitive cure accessible and available to all patients, strict implementation of the above suggested measures will go a long way in improving the quality (and quantity) of life in patients of beta-thalassemia major.

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This study presents a theoretical investigation of the effect of the aerosol vertical distribution on the aerosol radiative effect (ARE). Four aerosol composition models (dust, polluted dust, pollution and pure scattering aerosols) with varying aerosol vertical profiles are incorporated into a radiative transfer model. The simulations show interesting spectral dependence of the ARE on the aerosol layer height. ARE increases with the aerosol layer height in the ultraviolet (UV: 0.25–0.42 μm) and thermal-infrared (TH-IR: 4.0–20.0 μm) regions, whereas it decreases in the visible-near infrared (VIS-NIR: 0.42–4.0 μm) region. Changes in the ARE with aerosol layer height are associated with different dominant processes for each spectral region. The combination of molecular (Rayleigh) scattering and aerosol absorption is the key process in the UV region, whereas aerosol (Mie) scattering and atmospheric gaseous absorption are key players in the VIS-NIR region. The longwave emission fluxes are controlled by the environmental temperature at the aerosol layer level. ARE shows maximum sensitivity to the aerosol layer height in the TH-IR region, followed by the UV and VIS-NIR regions. These changes are significant even in relatively low aerosol loading cases (aerosol optical depth ∼0.2–0.3). Dust aerosols are the most sensitive to altitude followed by polluted dust and pollution in all three different wavelength regions. Differences in the sensitivity of the aerosol type are explained by the relative strength of their spectral absorption/scattering properties. The role of surface reflectivity on the overall altitude dependency is shown to be important in the VIS-NIR and UV regions, whereas it is insensitive in the TH-IR region. Our results indicate that the vertical distribution of water vapor with respect to the aerosol layer is an important factor in the ARE estimations. Therefore, improved estimations of the water vapor profiles are needed for the further reduction in uncertainties associated with the ARE estimation.

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