Gangotri glacier dynamics from multi-sensor SAR and optical data

The present study has analyzed dynamics of Gangotri glacier using multiple remote sensing (RS) datasets and ground based observations. Interferometric Synthetic Aperture Radar (InSAR) data pairs from European Remote Sensing satellite (ERS 1/2) tandem pair for spring of 1996, Sentinel-1 SAR pairs and Japanese's Advance Land Observation System (ALOS) PALSAR-2 SAR data for Spring of 2015 were used to derive glacier-surface velocity at seasonal time scale using Differential InSAR (DInSAR) techniques. Bi-static TanDEM-X (Experimental) data was used for the 1st time to estimate glacier surface elevation changes for a period of 22, 44, 88 days during summer of 2012 using InSAR techniques in this study. Annual glacier velocity was also estimated using temporal panchromatic data of LANDSAT-5 (30 m), LANDSAT-7/8 (15 m), Sentinel-2 (10 m) and Indian Remote Sensing Satellite IRS-1C/1D panchromatic (5 m) data during 1998–2019 with feature tracking approach. This study has estimated glacier surface velocity and surface elevation changes for the major parts of Gangotri glacier and its tributary glaciers using medium to high resolution optical and SAR datasets, at annual and seasonal time scale, which is an improvement over earlier studies, wherein snout based glacier recession or only main glacier velocities were reported. The velocity and slope were used to assess glacier-ice thickness distribution using Glabtop-2, slope dependent and laminar flow based methods over the Gangotri group of glaciers. The estimated ice thickness was estimated in the range of 58–550 m for the complete glacier while few small areas in middle &amp; upper regions carry higher thickness of about 607 m. The estimated glacier-ice thickness was found in the range of 58–67 m at the snout region. The estimation was validated using 2014 field measurements from Terrestrial Laser Scanner (TLS) for the first time and correlation was found to be 0.799 at snout of the glacier.</p

Randomized Clinical Trial of High-Dose Rifampicin With or Without Levofloxacin Versus Standard of Care for Pediatric Tuberculous Meningitis: The TBM-KIDS Trial

Background. Pediatric tuberculous meningitis (TBM) commonly causes death or disability. In adults, high-dose rifampicin may reduce mortality. The role of fluoroquinolones remains unclear. There have been no antimicrobial treatment trials for pediatric TBM. Methods. TBM-KIDS was a phase 2 open-label randomized trial among children with TBM in India and Malawi. Participants received isoniazid and pyrazinamide plus: (i) high-dose rifampicin (30 mg/kg) and ethambutol (R30HZE, arm 1); (ii) high-dose rifampicin and levofloxacin (R30HZL, arm 2); or (iii) standard-dose rifampicin and ethambutol (R15HZE, arm 3) for 8 weeks, followed by 10 months of standard treatment. Functional and neurocognitive outcomes were measured longitudinally using Modified Rankin Scale (MRS) and Mullen Scales of Early Learning (MSEL). Results. Of 2487 children prescreened, 79 were screened and 37 enrolled. Median age was 72 months; 49%, 43%, and 8% had stage I, II, and III disease, respectively. Grade 3 or higher adverse events occurred in 58%, 55%, and 36% of children in arms 1, 2, and 3, with 1 death (arm 1) and 6 early treatment discontinuations (4 in arm 1, 1 each in arms 2 and 3). By week 8, all children recovered to MRS score of 0 or 1. Average MSEL scores were significantly better in arm 1 than arm 3 in fine motor, receptive language, and expressive language domains (P < .01). Conclusions. In a pediatric TBM trial, functional outcomes were excellent overall. The trend toward higher frequency of adverse events but better neurocognitive outcomes in children receiving high-dose rifampicin requires confirmation in a larger trial. Clinical Trials Registration. NCT02958709

Red cell alloimmunization & role of advanced immunohaematological support in liver transplantation

Background & objectives: Transfusion support forms an integral part of liver transplantation programme. Advanced immunohaematology services are required to deal with complex serological problems that can complicate transfusion therapy in these patients. Here, we report on red cell alloimmunization and presence of alloimmunization in donors and patients undergoing liver transplantation in a tertiary care hospital in north India. Methods: Records of 1433 liver transplants performed from January 2009 to March 2015 were retrieved and reviewed. Antibody screening was performed both for liver donors, and recipients and antibody identification was performed for the screen-positive patients. Results: Of the 1433 liver recipients, 32 (2.3%) developed antibodies. Seventeen patients had one or more alloantibodies, five had autoantibodies with an underlying alloantibody and 10 had only autoantibodies in their plasma. The overall alloimmunization rate was 1.5 per cent with 25 alloantibodies identified in 22 patients. Anti-E was the most common specificity identified. Interpretation & conclusions: The presence of alloantibodies can complicate transfusion therapy in patients undergoing liver transplantation, who are already at a high risk of being heavily transfused owing to the nature of surgery and the haemostatic dysfunction from chronic liver disease. Therefore, screening for irregular red cell alloantibodies combined with a rational blood transfusion policy may be essential for these patients

Impact of antigenic exposures and role of molecular blood grouping in enhancing transfusion safety in chronically transfused thalassemics

Background: Red cell alloimmunization is an acknowledged complication of blood transfusion. Current transfusion practices for thalassemia do not cater to this risk. Serological phenotyping is usually not reliable in these cases unless performed before the first transfusion. Under such circumstances, molecular blood grouping is an effective alternative. Aim: To perform molecular blood group genotyping in chronically transfused thalassemia patients and assess the risk of antigenic exposure and incidence of alloimmunization with current transfusion protocols. Materials and Methods: Molecular blood group genotyping was performed for 47 chronically transfused thalassemia patients. Their 1-year transfusion records were retrieved to assess the antigenic exposure and the frequency thereof. Results: Of 47 patients, 6 were already alloimmunized (3 with anti-E and 3 with anti-K) and were receiving the corresponding antigen negative units. We observed that random selection of ABO and Rh D matched units resulted in 57.7% ±8.26% chance of Rh and Kell phenotype matching also. Forty-four patients had received one or more antigenic exposures at least once. The 6 already alloimmunized patients were further exposed to antigens other than the ones they were immunized to. During the study period, only one patient developed an alloantibody, anti-E with exposure to antigens C (92%) and/or E (32%) at each transfusion. Conclusion: Several factors apart from mere antigen exposure may influence the development of alloimmunization as most of our patients received antigenic exposures but not alloimmunized. Our data provide an impetus for future large-scale studies to understand the development of alloimmunization in such patients

Red cell alloimmunization and infectious marker status (human immunodeficiency virus, hepatitis B virus and hepatitis C virus) in multiply transfused thalassemia patients of North India

Background: Patients with thalassemia major are largely transfusion dependent and are thus exposed to a variety of risks such as transmission of infectious diseases, iron overload and alloimmunization. This study was performed to determine the prevalence of human immune deficiency virus (HIV), hepatitis B virus (HBV), hepatitis C virus (HCV) and red cell antibodies among multiple-transfused thalassemic patients in and around the national capital region. Materials and Methods: The Department of Transfusion Medicine, Indraprastha Apollo Hospitals, conducted this study in collaboration with the National Thalassemia Welfare Society over a period of 1 year starting February2011. Blood samples from the patients were tested for blood group, red cell alloantibody/ies, anti-HIV, anti-HCV and hepatitis B surface antigen (HBsAg) by ELISA and for the respective viral ribonucleic acid (RNA) or deoxyribonucleic acid (DNA) by nucleic acid testing (NAT). Results: A total of 462 thalassemics which consists of 290 males and 172 females were tested. The overall alloimmunization rate was 4.1% and anti-Kell was the most common antibody identified. Thirteen cases (2.8%) were positive for HBsAg by ELISA, 107 (23.1%) were reactive for anti HCV and 11 (2.38%) for anti HIV antibodies. Further screening and discriminatory assays by NAT confirmed the presence of HBV DNA in 11 cases, HIV RNA in 7 cases and HCV RNA in 48 cases. Conclusion: In spite of advances in Immunohematology and infectious marker testing in recent years, the rates of alloimmunization and infectious marker positivity remains high among multiply transfused patients like thalassemics. Provision of safe and adequate blood supply to these patients is a key to improving their quality-of-life and longevity

Antibody screening & identification in the general patient population at a tertiary care hospital in New Delhi, India

Background & objectives: The development of alloantibodies can significantly complicate transfusion therapy and results in difficulties in cross-matching of blood. Most literature on alloimmunization is limited to multitransfused individuals, with very few studies on the general hospital patients. This study was aimed at assessing the frequency and type of unexpected red cell antibodies in the general patient population at a multispecialty tertiary care centre in New Delhi, India. Methods: The results of 49,077 antibody screening tests carried out on patients, from January 2009 to December 2012 were analyzed. The clinical and transfusion records were reviewed. The data were compiled and statistically analysed. Results: A total of 49,077 (29,917; 60.96% males and 19,160; 39.04% females) patient samples were screened for the presence of unexpected antibodies. Antibody screening was positive in 403 patients (0.82%). In the serum samples of 164 patients only autoantibodies were identified, 27 revealed autoantibodies with one or more underlying alloantibodies, while 212 patients had only alloantibody/ies in their serum. The overall alloimmunization rate was 0.49 per cent. Antibodies against the Rh system were the most frequent (64.1%), the most common alloantibody identified being anti E (37.2%), followed by anti D (19.2%). Interpretation & conclusions: Since clinically significant antibodies are frequently detected in our patient population, antibody screening and if required, identification is the need of the hour. Since antibodies against the common Rh and Kell blood group antigens are the most frequent, provision of Rh and Kell matched red cells may be of protective value

Evaluation of bacterial inactivation in random donor platelets and single-donor apheresis platelets by the INTERCEPT blood system

Background: Blood transfusion of contaminated components is a potential source of sepsis by a wide range of known and unknown pathogens. Collection mechanism and storage conditions of platelets make them vulnerable for bacterial contamination. Several interventions aim to reduce the transfusion of contaminated platelet units; however, data suggest that contaminated platelet transfusion remains very common. Aim: A pathogen inactivation system, “INTERCEPT”, to inactivate bacteria in deliberately contaminated platelet units was implemented and evaluated. Materials and Methods: Five single-donor platelets (SDP) and five random donor platelets (RDP) were prepared after prior consent of donors. Both SDP and RDP units were deliberately contaminated by stable stock ATCC Staphylococcus aureus and Escherichia coli, respectively, with a known concentration of stock culture. Control samples were taken from the infected units and bacterial concentrations were quantified. The units were treated for pathogen inactivation with the INTERCEPT (Cerus Corporation, Concord, CA) Blood system for platelets (Amotosalen/UVA), as per the manufacturer's instructions for use. Post illumination, test samples were analyzed for any bacterial growth. Results: Post-illumination test samples did not result in any bacterial growth. A complete reduction of >6 log10S. aureus in SDP units and >6 log10Escherichia coli in RDP units was achieved. Conclusion: The INTERCEPT system has been shown to be very effective in our study for bacterial inactivation. Implementation of INTERCEPT may be used as a mitigation against any potential bacterial contamination in platelet components

A multivariate analysis to assess the effect of packed red cell transfusion and the unit age of transfused red cells on postoperative complications in patients undergoing cardiac surgeries

Background: Transfusion of blood components and age of transfused packed red cells (PRCs) are independent risk factors for morbidity and mortality in cardiac surgeries. Materials and Methods: We retrospectively examined data of patients undergoing cardiac surgery at our institute from January 1, 2012 to September 30, 2012. Details of transfusion (autologous and allogenic), postoperative length of stay (PLOS), postoperative complications were recorded along with other relevant details. The analysis was done in two stages, in the first both transfused and nontransfused individuals and in the second only transfused individuals were considered. Age of transfused red cells as a cause of morbidity was analyzed only in the second stage. Results: Of the 762 patients included in the study, 613 (80.4%) were males and 149 (19.6%) were females. Multivariate analysis revealed that factors like the number and age of transfused PRCs and age of the patient had significant bearing upon the morbidity. Morbidity was significantly higher in the patients transfused with allogenic PRCs when compared with the patients not receiving any transfusion irrespective of the age of transfused PRCs. Transfusion of PRC of over 21 days was associated with higher postoperative complications, but not with in-hospital mortality. Conclusion: In patients undergoing cardiac surgery, allogenic blood transfusion increases morbidity. The age of PRCs transfused has a significant bearing on morbidity, but not on in-hospital mortality. Blood transfusion services will therefore have to weigh the risks and benefits of providing blood older than 21 days in cardiac surgeries