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81.
Free zinc is considered to be the exchangeable and biological active form of zinc in serum, and is discussed to be a suitable biomarker for alterations in body zinc homeostasis and related diseases. Given that coronavirus disease 2019 (COVID-19) is characterized by a marked decrease in total serum zinc, and clinical data indicate that zinc status impacts the susceptibility and severity of the infection, we hypothesized that free zinc in serum might be altered in response to SARS-CoV-2 infection and may reflect disease severity. To test this hypothesis, free zinc concentrations in serum samples of survivors and nonsurvivors of COVID-19 were analyzed by fluorometric microassay. Similar to the reported total serum zinc deficit measured by total reflection X-ray fluorescence, free serum zinc in COVID-19 patients was considerably lower than that in control subjects, and surviving patients displayed significantly higher levels of free zinc than those of nonsurvivors (mean ± SD; 0.4 ± 0.2 nM vs. 0.2 ± 0.1 nM; p = 0.0004). In contrast to recovering total zinc concentrations (r = 0.706, p < 0.001) or the declining copper–zinc ratio (r = −0.646; p < 0.001), free zinc concentrations remained unaltered with time in COVID-19 nonsurvivors. Free serum zinc concentrations were particularly low in male as compared to female patients (mean ± SD; 0.4 ± 0.2 nM vs. 0.2 ± 0.1 nM; p = 0.0003). This is of particular interest, as the male sex is described as a risk factor for severe COVID-19. Overall, results indicate that depressed free serum zinc levels are associated with increased risk of death in COVID-19, suggesting that free zinc may serve as a novel prognostic marker for the severity and course of COVID-19.  相似文献   
82.
Biochemical and ultrastructural studies of ceramide galactosyltransferase (CGT) in a CGT-deficient mouse line (cgt-/-) were complemented by nerve conduction velocity (NCV) measurements in motor nerves (sciatic nerve in the hind limbs) of wild type (wt) and cgt-/- mice. Stimulation and recording electrodes were adapted to the small size of developing mice during their myelination period. Motor NCVs in wt mice ranged between 16 and 26 m/s but in cgt-/- mice between 6 and 13 m/s, which corresponds to the conductance of unmyelinated peripheral nerves.These electrophysiologic data provide additional functional parameters to the neuropathology of a new form of a dysmyelinosis.  相似文献   
83.
At the 2013 Academic Emergency Medicine global health consensus conference, a breakout session to develop a research agenda for resuscitation was held. Two articles are the result of that discussion. This second article addresses data collection, management, and analysis and regionalization of postresuscitation care, resuscitation programs, and research examples around the world and proposes a strategy to strengthen resuscitation research globally. There is a need for reliable global statistics on resuscitation, international standardization of data, and development of an electronic standard for reporting data. Regionalization of postresuscitation care is a priority area for future research. Large resuscitation clinical research networks are feasible and can give valuable data for improvement of service and outcomes. Low‐cost models of population‐based research, and emphasis on interventional and implementation studies that assess the clinical effects of programs and interventions, are needed to determine the most cost‐effective strategies to improve outcomes. The global challenge is how to adapt research findings to a developing world situation to have an effect internationally.  相似文献   
84.
In 10 cases of acute Guillain-Barré syndrome selection adsorption (SEA) of immunoglobulins was performed with IM TR350 columns (Asahi Medical, Japan). During this therapy the symptoms of 8 patients were reduced. Side effects were moderate and not specific for SEA. The columns removed large amounts of immunoglobulins, but also eliminated other plasma components.  相似文献   
85.
If customary drug mediated immunosuppressive therapy leads to intolerable side effects or is inefficient, extracorporeal elimination and untargeted or targeted immunoglobin therapy modulating the immune response are taken into consideration for the treatment of patients with autoimmune diseases. Both elimination and immunoglobulin therapy, are not alternatives but appear to act complementary, if sequentially applied. Selective immunoadsorption is increasingly applied for extracorporeal elimination and is able to replace plasma exchange therapy. Both, hydrophobic interaction chromatography and affinity chromatography are effective in given clinical conditions. Therapeutic affinity chromatography appears to be superior to hydrophobic interaction chromatography, if an effective, rapid elimination of the disease promoting agent is desired. Experience with therapeutic chromatography collected in the past, indicates that a rapid elimination of immunoglobulins and the subsequent intravenous infusion of 7S immunoglobulin is superior to elimination or untargeted immunomodulation alone. These experimental approaches lead to an extension of the available treatment modalities. However, controlled trials rather than anecdotal reports are needed, to provide substantial information.  相似文献   
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