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Cell-free extracts of nitrate-grown Penicillium politans NRC-510 could catalyze the hydrolytic deamination of adenosine to inosine maximally at pH 6.0 and 45 degrees C. However the same extracts could not catalyze the N-glycosidic bond cleavage of adenosine at pH 4.0, 6.0 and 8.0. Incubation of the extracts at 55 degrees C for 30 minutes caused about 31% loss in activity whereas incubation of the extracts at 60 degrees C for 15 minutes caused a complete loss of enzyme activity. Results indicated the absence of the involvement of sulfhydryl groups in the catalytic site of adenosine deaminase. The enzyme is inhibited by ethylene diamine tetraacetate indicating that adenosine deaminase is a metalloenzyme. MnCl2 and MgCl2 had a remarkable activating effect, whereas HgCl2, CaCl2 and ZnSO4 showed an inhibitory effect on enzyme activity. Dialyzing the extracts for 24 hours significantly increase deaminase activity by about 33%. The apparent K(m) value was calculated for adenosine and found to be 3.63 x 10(-3) M, which indicates high affinity of adenosine deaminase for its substrate adenosine.  相似文献   
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Reported cases encountered difficulty in differentiating between inflammatory carcinoma and breast edema caused by congestive heart failure especially if the breast edema is unilateral. Our presented case is an elderly woman with unilateral breast edema due to congestive heart failure that was initially suspected to have breast cancer based on clinical findings. However imaging studies showed breast edema pattern with no definite underlying mass. This edema was resolved with standard treatment of heart failure. Congestive heart failure may be a possible cause of unilateral breast edema especially in a patient with background of congestive heart failure.  相似文献   
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Titanium dioxide thin films immobilized over treated stainless steel were prepared using the pulsed electrophoretic deposition technique. The effects of process parameters (deposition time, applied voltage, initial concentration, and duty cycle) on photocatalytic efficiency and adhesion properties were investigated. To optimize the multiple properties of the thin film, a response surface methodology was combined with a desirability optimization methodology. Additionally, a quadratic model was established based on response surface analysis. The precision of the models was defined based on the analysis of variance (ANOVA), R2, and the normal plot of residuals. Then, a desirability function was used to optimize the multiple responses of the TiO2 thin film. The optimum values of applied voltage, catalyst concentration, duty cycle, and deposition time were 4 V, 16.34 g/L, 90% DC, and 150 s, respectively. Under these conditions, the decolorization efficiency of tested dye solution reached 82.75%. The values of critical charges LC1, LC2, and LC3 were 5.9 N, 12.5 N, and 16.7 N, respectively.  相似文献   
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Much progress has happened in understanding developmental vulnerability to preventable environmental hazards. Along with the improved insight, the perspective has widened, and developmental toxicity now involves latent effects that can result in delayed adverse effects in adults or at old age and additional effects that can be transgenerationally transferred to future generations. Although epidemiology and toxicology to an increasing degree are exploring the adverse effects from developmental exposures in human beings, the improved documentation has resulted in little progress in protection, and few environmental chemicals are currently regulated to protect against developmental toxicity, whether it be neurotoxicity, endocrine disruption or other adverse outcome. The desire to obtain a high degree of certainty and verification of the evidence used for decision‐making must be weighed against the costs and necessary duration of research, as well as the long‐term costs to human health because of delayed protection of vulnerable early‐life stages of human development and, possibly, future generations. Although two‐generation toxicology tests may be useful for initial test purposes, other rapidly emerging tools need to be seriously considered from computational chemistry and metabolomics to CLARITY‐BPA‐type designs, big data and population record linkage approaches that will allow efficient generation of new insight; epigenetic mechanisms may necessitate a set of additional regulatory tests to reveal such effects. As reflected by the Prenatal Programming and Toxicity (PPTOX) VI conference, the current scientific understanding and the timescales involved require an intensified approach to protect against preventable adverse health effects that can harm the next generation and generations to come. While further research is needed, the main emphasis should be on research translation and timely public health intervention to avoid serious, irreversible and perhaps transgenerational harm.  相似文献   
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IntroductionIn Southeast Michigan, active surveillance studies monitor influenza activity in hospitals, ambulatory clinics, and community households. Across five respiratory seasons, we assessed the contribution of data from each of the three networks towards improving our overall understanding of regional influenza circulation.MethodsAll three networks used case definitions for acute respiratory illness (ARI) and molecularly tested for influenza from research‐collected respiratory specimens. Age‐ and network‐stratified epidemic curves were created for influenza A and B. We compared stratified epidemic curves visually and by centering at seasonal midpoints.ResultsAcross all seasons (from 2014/2015 through 2018/2019), epidemic curves from each of the three networks were comparable in terms of both timing and magnitude. Small discrepancies in epidemics recorded by each network support previous conclusions about broader characteristics of particular influenza seasons.ConclusionInfluenza surveillance systems based in hospital, ambulatory clinic, and community household settings appear to provide largely similar information regarding regional epidemic activity. Together, multiple levels of influenza surveillance provide a detailed view of regional influenza epidemics, but a single surveillance system—regardless of population subgroup monitored—appears to be sufficient in providing vital information regarding community influenza epidemics.  相似文献   
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Cancer-associated cachexia (CAC) is a hypermetabolic syndrome characterized by unintended weight loss due to the atrophy of adipose tissue and skeletal muscle. A phenotypic switch from white to beige adipocytes, a phenomenon called browning, accelerates CAC by increasing the dissipation of energy as heat. Addressing the mechanisms of white adipose tissue (WAT) browning in CAC, we now show that cachexigenic tumors activate type 2 immunity in cachectic WAT, generating a neuroprotective environment that increases peripheral sympathetic activity. Increased sympathetic activation, in turn, results in increased neuronal catecholamine synthesis and secretion, β-adrenergic activation of adipocytes, and induction of WAT browning. Two genetic mouse models validated this progression of events. 1) Interleukin-4 receptor deficiency impeded the alternative activation of macrophages, reduced sympathetic activity, and restrained WAT browning, and 2) reduced catecholamine synthesis in peripheral dopamine β-hydroxylase (DBH)–deficient mice prevented cancer-induced WAT browning and adipose atrophy. Targeting the intraadipose macrophage-sympathetic neuron cross-talk represents a promising therapeutic approach to ameliorate cachexia in cancer patients.

Cancer-associated cachexia (CAC) is an energy balance disorder causing unintended loss of body weight due to depletion of white adipose tissue (WAT) and skeletal muscle. This multiorgan and multifactorial syndrome affects up to 80% of cancer patients and is responsible for more than 20% of cancer-associated deaths (1). CAC impedes the effectiveness of anticancer therapies and drastically lowers patients’ quality of life (2).A long list of tumor-borne, often proinflammatory factors, including interleukin-6 (IL-6) (3), parathyroid hormone–related protein (PTHrP) (4), leukemia inhibitory factor (LIF) (5), zinc α-glycoprotein (6), or growth differentiation factor-15 (GDF-15) (7), trigger CAC in mouse models. However, the signaling cascades and catabolic mechanisms that lead to adipose- and muscle tissue wasting remain insufficiently understood (8, 9). IL-6 and PTHrP are among the best studied of these “cachexokines.” Their presence or absence is decisive for the development of CAC in cancer patients and animal models (4, 1013). Thus, treatment with neutralizing antibodies against IL-6, the IL-6 receptor, or PTHrP ameliorates CAC in various mouse models of CAC (3, 4, 14, 15).CAC-associated WAT atrophy results from a metabolic switch toward decreased lipid synthesis and excessive degradation of lipid stores via enhanced triglyceride degradation (lipolysis) (9, 16). Induced lipolysis is observed in both humans and mice with CAC (17, 18). The absence of metabolic lipases at least partially ameliorates cachexia in murine cancer models (19). The metabolic or catabolic fates of lipolytic products, namely fatty acids (FAs) and glycerol, have not been fully clarified. These may provide energy and/or biosynthetic substrates for cancer cells to promote tumor growth or can be reesterified in WAT, creating an adenosine-triphosphate (ATP)-consuming futile metabolic cycle. Both of these pathways would contribute to the eventual loss of WAT during CAC (20).Another important catabolic pathway in CAC involves the direct oxidation of FAs and glycerol in adipose tissue. This process is promoted by the conversion of white to beige adipocytes called “WAT browning.” During WAT browning, adipocytes adopt a multilocular lipid droplet morphology; express genes that are typical for brown adipocytes, such as uncoupling protein-1 (UCP-1); exhibit elevated substrate oxidation rates; and dissipate energy as heat (21). WAT browning occurs in carcinogen-induced cancer models and genetically engineered mouse models as well as syngeneic and xenogeneic transplant models of murine cancers (3, 4, 22) and depends on the presence of cachexokines. WAT browning also occurs in humans suffering CAC or severe burn trauma (3, 2325), but the cellular and molecular mechanisms underlying catabolic WAT remodeling in CAC remain unclear.Here, we demonstrate that a macrophage-sympathetic neuron signaling axis generates a high β-adrenergic tone resulting in beige adipogenesis, increased lipid degradation, and WAT atrophy in murine models of CAC. This mechanism triggering hypermetabolism in CAC may offer targets for prevention or treatment of the disease.  相似文献   
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