Severe wildfire exposes remnant peat carbon stocks to increased post-fire drying.

The potential of high severity wildfires to increase global terrestrial carbon emissions and exacerbate future climatic warming is of international concern. Nowhere is this more prevalent than within high latitude regions where peatlands have, over millennia, accumulated legacy carbon stocks comparable to all human CO2 emissions since the beginning of the industrial revolution. Drying increases rates of peat decomposition and associated atmospheric and aquatic carbon emissions. The degree to which severe wildfires enhance drying under future climates and induce instability in peatland ecological communities and carbon stocks is unknown. Here we show that high burn severities increased post-fire evapotranspiration by 410% within a feather moss peatland by burning through the protective capping layer that restricts evaporative drying in response to low severity burns. High burn severities projected under future climates will therefore leave peatlands that dominate dry sub-humid regions across the boreal, on the edge of their climatic envelopes, more vulnerable to intense post-fire drying, inducing high rates of carbon loss to the atmosphere that amplify the direct combustion emissions.

Prevalence of bacterial contamination in platelet concentrates at the National Center of Blood Transfusion (Mexico).

OBJECTIVES: Most common bacterial sepsis associated with transfusion is caused by contaminated Platelet Concentrates (PC). The screening of PC to detect bacterial contamination is obligatory in Mexico, and it is carried out in quality control programs. In Mexico, the identification and molecular characterization of bacterial contaminants to detect contamination sources have not been implemented due to high costs; however, it is an actual current need. MATERIAL AND METHODS: One hundred PC were randomly selected and microbiologically analyzed. This sample size corresponds to 1% of the PC obtained by the National Center of Blood Transfusion (NCBT) in Mexico City according to the Official Mexican Standard NOM-253-SSA1-2012. Additionally, molecular biology tests were implemented in order to identify the possible contamination sources. RESULTS: Nine of the 100 PC analyzed (9%) showed bacterial contamination; analysis of the nucleotide sequences revealed the presence of characteristic microbiota from donor skin and soil. Diverse clonal relationship between the strains was identified in Staphylococcus epidermidis. CONCLUSION: Detection of contaminants associated with environmental and skin flora, shows the need to implement measures in the process of disinfecting skin at the site of phlebotomy and cleaning each of the areas involved in blood collection.

Assessment of immunological markers as mediators of graft vasculopathy development in heart transplantation.

Heart transplantation (HT) remains the treatment of choice for patients with end-stage heart failure. Cardiac allograft vasculopathy (CAV), a diffuse form of coronary atherosclerosis, is the major cause of death after the first year of HT. CAV is thought to be multifactorial in origin. Although nonimmune factors may play a role in CAV development, it is primarily an immune-mediated disease. CAV is diagnosed by routine annual coronary angiography, and usually when diagnosed, the disease is advanced. There is a need to develop noninvasive surrogate markers for early detection. For this purpose, careful immune monitoring and graft histologic assessment are mandatory. The main objective of this study was the assessment of immunologic markers as mediators of CAV development in HT. Flow cytometry was performed to assess peripheral blood mononuclear cell populations forming CD3, CD4, CD8, CD19, CD56, Th1 (CD3+IFNγ+) or Treg (CD4+CD25(high)FoxP3+) markers among 20 de novo HT recipients. The control group included 13 patients who were more than 2 years post-HT (four with and nine without CAV) as well as 20 healthy subjects. CAV-related events over 2 years' follow-up correlated with the Th1/Treg ratio. An increased Th1 lymphocyte percentage was detected over the follow-up. Patients with medium and high Th1/Treg ratios showed higher acute rejection scores as well as greater incidences of CAV. These results indicated that the Th1/Treg ratio may represent a valuable marker to monitor allospecific T-cell responses in peripheral blood. Changes in the Th1/Treg ratio may help in the early detection of patients at risk for CAV. More studies with longer follow-up are needed to confirm these preliminary results.

An assessment of a mesocosm approach to the study of microbial respiration in a sandy unsaturated zone.

Microbial respiration rates were determined through a 3.2 m thick, sandy unsaturated zone in a 2.4 m diameter x 4.6 m high mesocosm. The mesocosm was maintained under near constant temperature (18 degrees to 23 degrees C) and reached steady moisture content conditions after several hundred days. Soil-gas CO2 concentrations in the mesocosm ranged from 0.09% to 3.31% and increased with depth. Respiration rates within the mesocosm were quantified over a 342-day period using measured CO2 concentrations and a transient, one-dimensional finite-element model. Microbial respiration rates were 2 x 10(-1) micrograms C.g-1.d-1 throughout most of the system, but decreased to 10(-4) to 10(-3) micrograms C.g-1.d-1 within the capillary fringe. Microbial respiration rates were also determined in minicosms (500 g sample mass) over a range in temperatures (4 degrees to 30 degrees C) and volumetric moisture contents (0.044 to 0.37). The functional dependence of CO2 production on temperature and soil-moisture content was similar for the two scales of laboratory observation. Respiration rates in the minicosms, for temperatures and moisture contents in the mesocosm, were up to an order of magnitude greater than those determined for the mesocosm. The higher respiration rates in the minicosms, compared to the mesocosm, were attributed to greater disturbance of the samples and to shorter acclimation time in the minicosms. Extrapolating the laboratory respiration rates to field conditions yielded rates that were two to three orders of magnitude greater than rates previously determined in situ for C-horizon material. Results show that in situ microbial reaction rates determined using disturbed samples in minicosms and mesocosms yielded respiration rates that greatly exceeded field conditions. Mesocosms can, however, provide a useful environment for conducting process-related research in unsaturated environments.

Neutrophil and T lymphocyte characteristics of two patients with hyper-IgE syndrome.

Immunologic parameters including quantitative and qualitative immunoglobulin studies, various T cell functions and neutrophil chemotaxis were evaluated in two patients with the Hyper-IgE syndrome. Both exhibited pruritic dermatitis in locations atypical for atopic dermatitis, marked elevations in serum IgE levels (to 40,000 IU/ml), recurrent staphylococcal abscesses, coarse facial features and variable chemotactic defects characteristic of this syndrome. Both patients responded favorably to courses of trimethoprim-sulfamethoxazole, particularly in helping control the cutaneous infections. We believe that this is a useful therapeutic alternative to anti-staphylococcal antibiotics and prophylactic treatment has permitted therapeutic response. Serum IgG, IgG subclasses, IgM, and IgA were normal for age. Serum IgD was markedly deficient in one patient. Functional IgM was normal with positive isohemagglutinin titers. IgG poliovirus titers were present in both patients; however, tetanus titers were not detectable in either patient, despite repeated immunizations. Despite normal E rosette numbers, subtle T cell abnormalities were noted with variable responses to both in vivo SK-SD, candida, and mumps skin tests and in vitro PHA-, Con A-tetanus-induced lymphocyte proliferation. Lymphocyte production of macrophage inhibitory factor and interferon and responsiveness in a mixed lymphocyte culture were normal in both patients. Considerable Con-A-induced suppressor cell activity was present in one patient, but diminished in the other. In vivo chemotaxis determined by a Rebuck skin window, revealed a markedly delayed PMN migration in both patients during a time when both patients were clinically free of furunculosis or dermatitis.(ABSTRACT TRUNCATED AT 250 WORDS)

Hodgkin's disease involving the urinary bladder diagnosed by urinary cytology: a case report.

A unique case of lymphocyte depletion Hodgkin's disease of the urinary bladder in a 91-year-old woman was diagnosed by exfoliative cytology on a single passed urine specimen. Subsequent bladder biopsy confirmed the diagnosis. Retrospectively, it was ascertained that the patient had had a previous diagnosis of Hodgkin's disease based on biopsy of a cervical lymph node ten years previously. This is the first case to be reported in which the presence of Reed Sternberg cells in a cytologic preparation of the urine led to the diagnosis of Hodgkin's disease with involvement of the bladder.

Limitations of continuous ambulatory electrocardiogram monitoring for detecting coronary artery disease.

To assess the value of continuous ambulatory electrocardiogram (ECG) monitoring for detecting coronary artery disease in symptomatic patients, we evaluated 70 patients with chest pain and normal resting ECGs prospectively by calibrated ambulatory monitoring, graded treadmill exercise, and selective coronary cineangiography. Ischemic-type ST-wave changes were detected by monitoring in 24 of the 39 patients with coronary artery disease (62% sensitivity). Twenty-six of the 39 patients had a positive treadmill (67% sensitivity). Of the 31 patients without coronary disease on angiography, 19 had negative monitoring studies (61% specificity). The treadmill was negative in 23 of these 31 patients (75% specificity). When the results of both tests were combined, 85% of the cases of coronary artery disease were detected, but only 52% of the patients without disease had negative studies. We conclude that continuous ambulatory monitoring is of limited value for detecting or excluding coronary artery disease in symptomatic patients with normal resting ECGs.