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101.
Multiple sclerosis is characterised by inflammatory neurodegeneration, with axonal injury and neuronal cell death occurring in parallel to demyelination. Regarding the molecular mechanisms responsible for demyelination and axonopathy, energy failure, aberrant expression of ion channels and excitotoxicity have been suggested to lead to Ca2+ overload and subsequent activation of calcium‐dependent damage pathways. Thus, the inhibition of Ca2+ influx by pharmacological modulation of Ca2+ channels may represent a novel neuroprotective strategy in the treatment of secondary axonopathy. We therefore investigated the effects of the L‐type voltage‐gated calcium channel blocker nimodipine in two different models of mouse experimental autoimmune encephalomyelitis (EAE ), an established experimental paradigm for multiple sclerosis. We show that preventive application of nimodipine (10 mg/kg per day) starting on the day of induction had ameliorating effects on EAE in SJL /J mice immunised with encephalitic myelin peptide PLP 139–151, specifically in late‐stage disease. Furthermore, supporting these data, administration of nimodipine to MOG 35–55‐immunised C57BL /6 mice starting at the peak of pre‐established disease, also led to a significant decrease in disease score, indicating a protective effect on secondary CNS damage. Histological analysis confirmed that nimodipine attenuated demyelination, axonal loss and pathological axonal β‐amyloid precursor protein accumulation in the cerebellum and spinal cord in the chronic phase of disease. Of note, we observed no effects of nimodipine on the peripheral immune response in EAE mice with regard to distribution, antigen‐specific proliferation or activation patterns of lymphocytes. Taken together, our data suggest a CNS ‐specific effect of L‐type voltage‐gated calcium channel blockade to inflammation‐induced neurodegeneration.

  相似文献   
102.

Purpose

Seafood life cycle assessment (LCA) studies have adopted the primary production required (PPR) indicator to account for the impact of these production systems (e.g., capture fisheries or aquaculture) on the ecosystems they harvest wild inputs from. However, there exists a large diversity in the application of methods to calculate PPR, and current practice often does not consider species- and ecosystem-specific factors. Here, we critically examine current practice and propose a refined method for applying the PPR metric in seafood LCAs.

Methods

We surveyed seafood LCAs that quantify PPR, or its derivatives, to examine the diversity of practice. We then defined and applied a refined method to a case study of the average Norwegian salmon feed in 2012. This refined method incorporates species-specific fishmeal and oil yields, source ecosystem-specific transfer efficiencies and expresses results as a percentage of total ecosystem production that PPR represents. Results were compared to those using previously applied methods based on the literature review, and the impact of uncertainty and natural variability of key input parameters was also assessed using Monte Carlo simulation.

Results and discussion

From the literature review, most studies do not incorporate species-specific fishmeal and oil yields or ecosystem-specific transfer efficiencies when calculating PPR. Our proposed method, which incorporated source species- and ecosystem-specific values for these parameters, provides far greater resolution of PPR than when employing global average values. When alternative methods to calculate PPR were applied to marine inputs to Norwegian salmon feeds, resulting PPR values were similar for some sources of fishmeal and oil. For other species, such as Atlantic herring from ecosystems with low transfer efficiencies, there was a large divergence in resulting PPR values. For combined inputs to Norwegian salmon feeds in 2012, the refined method resulted in a total PPR value that is three times higher than would result using the currently standard method signaling that previous LCA research may have substantially underestimated the marine biotic impacts of fishery products.

Conclusions

While there exists a great diversity of practice in the application of the PPR indicator in seafood LCA, the refined method should be adopted for future LCA studies to be more specific to the context of the study.
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To study the metabolic interactions between mesophyll and bundle-sheath cells of C4 plants, protein kinases possibly involved in the regulatory processes and signal transduction pathways have been cloned and characterized. A receptor-like protein kinase (RLK) cDNA clone from the C4 plant Sorghum bicolor (L.) Moench has been identified. The deduced protein was designated SbRLK1 for receptor-like protein kinase from S. bicolor. The putative cytoplasmic domain of SbRLK1 contains all amino acids that are characteristic of protein kinases. The extracellular domain contains five leucine-rich repeats. The mRNA of the SbRLK1 gene accumulated to much higher levels in mesophyll cells than in the bundle-sheath and was almost undetectable in roots. This expression pattern indicates that SbRLK1 might be involved in the regulation of specific processes in mesophyll cells. Received: 13 August 1998 / Accepted: 22 December 1998  相似文献   
106.
Kyasanur Forest disease virus (KFDV) and the closely related Alkhurma hemorrhagic disease virus (AHFV) are emerging flaviviruses that cause severe viral hemorrhagic fevers in humans. Increasing geographical expansion and case numbers, particularly of KFDV in southwest India, class these viruses as a public health threat. Viral pathogenesis is not well understood and additional vaccines and antivirals are needed to effectively counter the impact of these viruses. However, current animal models of KFDV pathogenesis do not accurately reproduce viral tissue tropism or clinical outcomes observed in humans. Here, we show that pigtailed macaques (Macaca nemestrina) infected with KFDV or AHFV develop viremia that peaks 2 to 4 days following inoculation. Over the course of infection, animals developed lymphocytopenia, thrombocytopenia, and elevated liver enzymes. Infected animals exhibited hallmark signs of human disease characterized by a flushed appearance, piloerection, dehydration, loss of appetite, weakness, and hemorrhagic signs including epistaxis. Virus was commonly present in the gastrointestinal tract, consistent with human disease caused by KFDV and AHFV where gastrointestinal symptoms (hemorrhage, vomiting, diarrhea) are common. Importantly, RNAseq of whole blood revealed that KFDV downregulated gene expression of key clotting factors that was not observed during AHFV infection, consistent with increased severity of KFDV disease observed in this model. This work characterizes a nonhuman primate model for KFDV and AHFV that closely resembles human disease for further utilization in understanding host immunity and development of antiviral countermeasures.  相似文献   
107.
A survey of academics in Germany shows a lack of and a great demand for training in leadership skills. Subject Categories: Careers, Science Policy & Publishing

Success and productivity in science is measured largely by the number of publications in scientific journals and the acquisition of third‐party funding to finance further research (Detsky, 2011). Consequently, as young researchers advance in their careers, they become highly trained in directly related skills, such as scientific writing, so as to increase their chances in securing publications and grants. Acquiring leadership skills, however, is often neglected as these do not contribute to the evaluation of scientific success (Detsky, 2011). Therefore, an early‐career researcher may become leader of a research group based on publication record and solicitation of third‐party funding, but without any training of leadership or team management skills (Lashuel, 2020). Leadership, in the context of academic research, requires a unique list of competencies, knowledge and skills in addition to “traditional” leadership skills (Anthony & Antony, 2017), such as managing change, adaptability, empathy, motivating individuals, and setting direction and vision among others. Academic leadership also requires promoting the research group’s reputation, networking, protecting staff autonomy, promoting academic credibility, and managing complexity (Anthony & Antony, 2017).  相似文献   
108.
Historically, large areas of forest in Europe were managed as coppice woodland to produce wood‐based fuel for the smelting industry. We hypothesized that this practice produced a legacy effect on current forest ecosystem properties. Specifically, we hypothesized that the historical form of coppicing may have produced a legacy of elevated stocks of soil organic carbon (SOC), nutrients and black carbon (BC) in soil as fire was routinely used in coppiced woodland to clear land. We further hypothesized that these changes in soil properties would result in increased biodiversity. To test these hypotheses, we sampled the surface soil (0–5, 5–10 and 10–20 cm) from a chronosequence of forest sites found in the Siegerland (Germany) that had been coppiced and burned 1, 2, 3.5, 6, 8, 11 and 17 years before present. Mature beech and spruce forests (i.e., >60 years) were also sampled as reference sites: to provide a hint of what might occur in the absence of human intervention. We measured stocks of SOC, BC, NO3‐N, P, K, Mg, as well as cation exchange and water‐holding capacity, and we mapped plant composition to calculate species richness and evenness. The results showed that coppicing in combination with burning soil and litter improved soil nutrient availability, enhanced biodiversity and increased SOC stocks. The SOC stocks and biodiversity were increased by a factor of three relative to those in the mature beech and spruce forests. This study shows that traditional coppicing practice may facilitate net C accrual rates of 20 t ha?1 yr?1 and maintain high biodiversity, indicating that aspects of traditional practice could be applied in current forest management to foster biodiversity and to mitigate climate change.  相似文献   
109.
The human hCLCA1 and murine mCLCA3 (chloride channels, calcium-activated) have recently been identified as promising therapeutic targets in asthma. Recurrent airway obstruction in horses is an important animal model of human asthma. Here, we have cloned and characterized the first equine CLCA family member, eCLCA1. The 913 amino acids eCLCA1 polypeptide forms a 120-kDa transmembrane glycoprotein that is processed to an 80-kDa protein in vivo. Three single nucleotide polymorphisms were detected in the eCLCA1 coding region in 14 horses, resulting in two amino acid changes (485H/R and 490V/L). However, no functional differences were recorded between the channel properties of the two variants in transfected HEK293 cells. The eCLCA1 protein was detected immunohistochemically in mucin-producing cells in the respiratory and intestinal tracts, cutaneous sweat glands, and renal mucous glands. Strong overexpression of eCLCA1 was observed in the airways of horses with recurrent airway obstruction using Northern blot hybridization, Western blotting, immunohistochemistry, and real-time quantitative RT-PCR. The results suggest that spontaneous or experimental recurrent airway obstruction in horses may serve as a model to study the role of CLCA homologs in chronic airway disease with overproduction of mucins.  相似文献   
110.
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