Effects of rapid urbanisation on the urban thermal environment between 1990 and 2011 in Dhaka Megacity, Bangladesh

This study investigates the influence of land-use/land-cover (LULC) change on land surface temperature (LST) in Dhaka Megacity, Bangladesh during a period of rapid urbanisation. LST was derived from Landsat 5 TM scenes captured in 1990, 2000 and 2011 and compared to contemporaneous LULC maps. We compared index-based and linear spectral mixture analysis (LSMA) techniques for modelling LST. LSMA derived biophysical parameters corresponded more strongly to LST than those produced using index-based parameters. Results indicated that vegetation and water surfaces had relatively stable LST but it increased by around 2 °C when these surfaces were converted to built-up areas with extensive impervious surfaces. Knowledge of the expected change in LST when one land-cover is converted to another can inform land planners of the potential impact of future changes and urges the development of better management strategies

Coeliac disease: an update for pathologists

Coeliac disease is the manifestation of an immune hypersensitivity reaction towards gluten and related proteins, in genetically predisposed people. Although the precise pathogenesis of this condition remains to be fully elucidated, it is probably multifactorial in origin. The diagnosis of coeliac disease has traditionally depended on intestinal biopsies alone; nowadays, the diagnosis has been expanded to include an array of serological markers. This review is intended to offer pathologists an update of the relevant history and immunopathology pertaining to coeliac disease and also to offer recommendations on the ongoing responsibilities of the pathologist in the diagnosis and reporting of coeliac disease

MCO IMPACT ABSORBERS USING CRUSHABLE TUBES 1

ABSTRACT Spent nuclear fuel from the Hanford N-Reactor is currently stored in pools, the K-East and K-West basins. As part of Hanford's Decontamination and Decommissioning effort, this fuel is to be placed in dry interim storage in the Canister Storage Building (CSB). The storage arrangement consists of an array of sealed vertical storage tubes, each capable of holding two Multi-Canister Overpacks (MCO), one on top of the other. To protect the MCOs from damage during loading, two impact absorbers are used, one placed below the lower MCO and one between the lower and upper MCOs. Since the MCOs can only move axially in the tube, the impact absorbers need only function in one axis. The impact absorber consists of an array of mild steel tubes arranged symmetrically between relatively rigid end plates. Under impact load, the tubes collapse by a process of regular crippling which safely absorbs the energy of the dropped MCO without exceeding load or deflection limits. In designing tubes which would crush reliably, consistently, and smoothly, three primary design challenges were met: 1. Development of a physical configuration to ensure a stable buckling mode to avoid gross collapse. 2. Mitigation of the force spike which occurrs at the initiation of tube crush. 3. Choice of a design configuration which accommodated material property, dimensional, and temperature variations while keeping the average crush force within a narrow design envelope. The successful approach to these challenges is discussed in this paper, including results of full scale prototype testing

Detection of Species-Specific Helicobacter Ribosomal DNA in Intestinal Biopsy Samples from a Population-Based Cohort of Patients with Ulcerative Colitis

The inflammatory bowel diseases are considered an abnormal host immune response to an environmental stimulus. Evidence suggests a role for intestinal bacteria in initiating and/or providing an ongoing stimulus for inflammation in inflammatory bowel disease. Helicobacter pylori is the major cause of active chronic gastritis and peptic ulcers in humans and has been linked to gastric carcinoma and lymphoma. Studies in various animal models, particularly mice, have identified enterohepatic Helicobacter species that are capable of causing hepatitis and enterocolitis. We hypothesize that Helicobacter species may have a role in maintaining inflammation in humans with inflammatory bowel disease. In order to investigate this, biopsy specimens were obtained from patients with and without inflammatory bowel disease. DNA was extracted from the tissues and subjected to PCR with primers designed to detect the ribosomal DNA of members of the Helicobacter species. DNA from six biopsy samples from 60 inflammatory bowel disease patients tested positive. This included 5 of 33 ulcerative colitis patients that were positive compared to 0 of 29 age-matched controls (P < 0.04). Sequencing of the bands produced by PCR amplification revealed ≥99% homology with H. pylori. These results indicate that a member of the Helicobacter species may be involved in some cases of ulcerative colitis

Malignancies in a renal transplant population: The St. Michael's Hospital experience

Introduction: Previous publications have shown an increased incidence of various malignancies amongst renal transplant populations. The objective of this study was to analyze the rate and types of malignancies occurring in the St. Michael's Hospital renal transplant population and to determine whether our results were comparable to those previously published. Methods: After approval by the hospital's research ethic board, review of the records and pathology of the 1584 patients in the renal transplant clinic database patients was performed. The reports dated back to the year 1970. Results: Amongst the 1584 renal transplant patients, 106 patients with 132 dysplastic and malignant posttransplant lesions were identified. The highest incidence amid the malignancies was in nonmelanoma skin malignancies squamous cell carcinoma (SCC), basal cell carcinoma, and Kaposi sarcoma, with a total of 32 patients having 54 separate tumors (2.02% of all patients, 43.2% of tumors). Following skin tumors in incidence were genitourinary (28 tumors), gastrointestinal tract (GIT) lesions (8 adenocarcinomas, 14 dysplastic lesions, 1 low grade neuroendocrine tumor/carcinoid), posttransplant lymphoproliferative disorders (PTLDs) (10 cases), gynecologic (6 carcinomas), cervical/anal/vulvar dysplasia and invasive (SCCs) (4), and thyroid (3 papillary tumors). Nine patients had tumors of multiple sites/types. With respect to outcome, 14 patients died of malignancy, with the highest mortality being in the GIT malignancies (six patients). Second in mortality were the PTLD and skin tumor groups. Discussion: Information on the incidence and outcome of various malignancies in renal transplant patients is important in designing guidelines for the follow-up of these patients regarding tumor screening and prevention. The rate of malignancies in our group is comparable to that reported in other centers

Termination of CD40L co-stimulation promotes human B cell differentiation into antibody-secreting cells

Human naïve B cells are notoriously difficult to differentiate into antibody-secreting cells (ASCs) in vitro while maintaining sufficient cell numbers to evaluate the differentiation process. B cells require T follicular helper (TFH ) cell-derived signals like CD40L and IL-21 during germinal center (GC) responses to undergo differentiation into ASCs. Cognate interactions between B and TFH cells are transient; after TFH contact, B cells cycle between GC light and dark zones where TFH contact is present and absent, respectively. Here, we elucidated that the efficacy of naïve B cells in ACS differentiation is dramatically enhanced by the release of CD40L stimulation. Multiparameter phospho-flow and transcription factor (TF)-flow cytometry revealed that termination of CD40L stimulation downmodulates NF-κB and STAT3 signaling. Furthermore, the termination of CD40 signaling downmodulates C-MYC, while promoting ASC TFs BLIMP1 and XBP-1s. Reduced levels of C-MYC in the differentiating B cells are later associated with crucial downmodulation of the B cell signature TF PAX5 specifically upon the termination of CD40 signaling, resulting in the differentiation of BLIMP1 high expressing cells into ASCs. The data presented here are the first steps to provide further insights how the transient nature of CD40 signaling is in fact needed for efficient human naïve B cell differentiation to ASCs

Evaluation and prognostic significance of human tissue kallikrein-related peptidase 6 (KLK6) in colorectal cancer

The prognosis of patients with colorectal cancer (CRC) is assessed through conventional clinicopathological parameters, which are not always accurate. Members of the human kallikrein-related peptidases gene family represent potential cancer biomarkers. The aim of this study was to investigate the expression of human tissue kallikrein-related peptidase 6 (KLK6) by immunohistochemistry in CRC to correlate this expression with various histopathological and clinical variables, and to evaluate its significance as a predictor of disease outcome. KLK6 expression was evaluated by immunohistochemistry and an expression score was calculated for each case. In CRC, KLK6 expression was decreased compared to normal colonic mucosa. A statistically significant, positive association was observed between KLK6 and tumor stage (p=0.036), lymph node metastases (p=0.030), and liver metastases (p=0.025). Univariate analysis showed that KLK6 expression and stage had statistically significant correlation with disease-free survival (p=0.045 and p&lt;0.001, respectively) and overall survival (p=0.027 and p&lt;0.001, respectively). Cox multivariate analysis showed that KLK6 expression was an independent predictor of unfavorable overall survival (p=0.041). Kaplan-Meier survival curves showed that KLK6-positive patients have statistically significant lower disease-free and overall survival. In conclusion, KLK6 immunostaining is an independent prognostic marker in patients with CRC. © 2012 Elsevier GmbH

Plasma-derived human antithrombin attenuates ventilator-induced coagulopathy but not inflammation in a Streptococcus pneumoniae pneumonia model in rats.

Item does not contain fulltextBACKGROUND: Mechanical ventilation exaggerates pneumonia-associated pulmonary coagulopathy and inflammation. We hypothesized that the administration of plasma-derived human antithrombin (AT), one of the natural inhibitors of coagulation, prevents ventilator-induced pulmonary coagulopathy, inflammation and bacterial outgrowth in a Streptococcus pneumoniae pneumonia model in rats. METHODS: Forty-eight hours after induction of S. pneumoniae pneumonia rats were subjected to mechanical ventilation (tidal volume 12 mL kg(-1), positive end-expiratory pressure 0 cmH(2)O and inspired oxygen fraction 40%). Rats were randomized to systemic treatment with AT (250 IU administered intravenously (i.v.) before the start of mechanical ventilation) or placebo (saline). Non-ventilated, non-infected rats and non-ventilated rats with pneumonia served as controls. The primary endpoints were pulmonary coagulation and inflammation in bronchoalveolar lavage fluid (BALF). RESULTS: Pneumonia was characterized by local activation of coagulation and inhibition of fibrinolysis, resulting in increased levels of fibrin degradation products and fibrin deposition in the lung. Mechanical ventilation exaggerated pulmonary coagulopathy and inflammation. Systemic administration of AT led to supra-normal BALF levels of AT and decreased ventilator-associated activation of coagulation. AT neither affected pulmonary inflammation nor bacterial outgrowth from the lungs or blood. CONCLUSIONS: Plasma-derived human AT attenuates ventilator-induced coagulopathy, but not inflammation and bacterial outgrowth in a S. pneumoniae pneumonia model in rats.1 maart 201