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Introduction: Ca 2+ regulatory excitation-contraction coupling properties are key topics of interest in the development of work-related muscle myalgia and may constitute an underlying cause of muscle pain and loss of force generating capacity., Method: A well-established rat model of high repetition high force (HRHF) work was used to investigate if such exposure leads to an increase in cytosolic Ca 2+ concentration ([Ca 2+ ] i ) and changes in sarcoplasmic reticulum (SR) vesicle Ca 2+ uptake and release rates., Result: Six weeks exposure of rats to HRHF increased indicators of fatigue, pain behaviors, and [Ca 2+ ] i , the latter implied by around 50-100% increases in pCam, as well as in the Ca 2+ handling proteins RyR1 and Casq1 accompanied by an ∼10% increased SR Ca 2+ uptake rate in extensor and flexor muscles compared to those of control rats. This demonstrated a work-related altered myocellular Ca 2+ regulation, SR Ca 2+ handling, and SR protein expression., Discussion: These disturbances may mirror intracellular changes in early stages of human work-related myalgic muscle. Increased uptake of Ca 2+ into the SR may reflect an early adaptation to avoid a sustained detrimental increase in [Ca 2+ ] i similar to the previous findings of deteriorated Ca 2+ regulation and impaired function in fatigued human muscle., Competing Interests: The authors declare that there are no conflicts of interest to disclose., (Copyright © 2019 J. Hadrevi et al.)

Organophosphates are highly toxic substances, which cause severe brain damage. The hallmark of the brain injury is major convulsions. The goal of this study was to assess the spatial and temporal MR changes in the brain of paraoxon intoxicated rats. T2-weighted MRI and ¹H-MR-spectroscopy were conducted before intoxication, 3 h, 24 h, and 8 days postintoxication. T2 prolongation mainly in the thalami and cortex was evident as early as 3 h after intoxication (4-6% increase in T2 values, P < 0.05). On spectroscopy, N-acetyl aspartate (NAA)/creatine and NAA/choline levels significantly decreased 3 h postintoxication (>20% decrease, P < 0.005), and 3 h lactate peak was evident in all intoxicated animals. On the 8th day, although very little T2 changes were evident, NAA/creatine and choline/creatine were significantly decreased (>15%, P < 0.05). Animals who succumbed had extensive cortical edema, significant higher lactate levels and a significant decrease in NAA/creatine and NAA/choline levels compared to animals which survived the experiment. Organophosphates-induced brain damage is obvious on MR data already 3 h postintoxication. In vivo spectroscopic changes are more sensitive for assessing long-term injury than T2-weighted MR imaging. Early spectroscopic findings might be used as biomarkers for the severity of the intoxication and might predict early survival., (Copyright © 2012 Wiley Periodicals, Inc.)

A rapid and simple procedure for enantioselective preparation of 2- and 3-substituted 2,3-dihydro[1,4]dioxino[2,3-b]pyridine derivatives (A and B, respectively) is described. The enantiomeric purity of each isomer was determined by capillary electrophoresis using a dual-cyclodextrin system (S-beta-CD/beta-CD) dissolved in formic acid-ammonia buffer (pH 4, ionic strength 50 mM)., (Copyright 2004 Wiley-Liss, Inc.)

Proliferative responses by blood and tumor lymphocytes to plant mitogens and allogeneic leukocyte antigens were tested concomitantly on 12 patients with Hodgkin's disease, 10 with chronic lymphocytic leukemia, and seven with non-Hodgkin's lymphomas. In 13 control studies, 3H-thymidine incorporation by blood and lymph node lymphocytes was brisk and, overall, comparable. With Hodgkin's disease, where extent of disease involvement and lymphocyte-depleted tumor histology were factors in the degree of responsiveness, incorporation was higher or at least comparable by tumor lymphocytes when compared with incorporation by autologous blood lymphocytes. Lymph node lymphocytes, especially with clinically stable disease, were more responsive than blood lymphocytes with chronic lymphocytic leukemia. Conversely, tumor lymphocytes were hyporesponsive compared with autologous blood lymphocytes with non-Hodgkin's lymphomas, where prognosis is usually less favorable than with chronic lymphocytic leukemia. Plasma from four out of 33 patients, although not lymphocytotoxic, inhibited lymphoproliferative responses.