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1.
This article briefly reviews the classical cell cycle studies using oocytes and zygotes of mainly amphibians in the past century. The discussions are focused on the investigations into the cytoplasmic factors that regulate meiosis during oocyte maturation and the initiation of mitosis during fertilisation, which were carried out in the author's lab between 1967 and 1987. This chronicle traces the development of the problems and the direction in which their solutions were attempted in the course of these investigations. The author tries to answer the following questions: why he decided to study oocyte maturation, how he discovered progesterone as a maturation-inducing hormone, how he discovered and characterised the cytoplasmic regulators of the cell cycle, Maturation-Promoting Factor (MPF) and Cyto-Static Factor (CSF), and how he invented the method of observing cell cycle processes in a cytoplasmic extract in vitro.  相似文献   
2.
《Cytokine》2015,74(2):283-287
Encephalitic listeriosis in sheep is a life-threatening disease. However, little is known about the cytokine response and their predictive value in this disease. The aim of present study was to assess the prognostic significance of Tumor Necrosis Factor-α (TNF-α), Interleukin-12(p40) (IL-12 p40), Interleukin-6 (IL-6), and Interleukin 10 (IL-10) levels in cerebrospinal fluid (CSF) in sheep with encephalitic listeriosis. Fifty-nine ewes in 14 flocks were diagnosed clinically as having listeriosis. CSF was collected and subjected to bacteriological examination and estimation of selected cytokines. Twenty-eight ewes were confirmed to be infected with Listeria monocytogenes. Based on antimicrobial sensitivity test, sheep were treated and the outcome was recorded as survivors (n = 10) and non-survivors (n = 18). Cutoff points for CSF cytokines were determined by Receiver operating characteristic analysis (ROC). Association between levels of CSF cytokines and outcome of listeriosis was assessed by logistic regression. TNF-α, IL-6 and IL-12(p40) levels as well as TNF-α/IL-10 ratio were significantly higher in non-survivors than survivors (p = 0.002, 0.0021, 0.0033, and 0.001, respectively). However, IL-10 level was significantly lower in non-survivors than survivors (p = 0.0058). ROC analysis revealed that IL-6 and TNF-α/IL-10 ratio had the highest AUC values (0.98, 0.984, respectively). Final multivariate logistic regression model showed that TNF-α/IL-10 ratio was the only variable that has predictive value for mortality in diseased sheep (p: 0.001; OR: 7.2; 95% CI: 5.7–9.8). TNF-α showed a positive correlation with IL-12β (r = 0.917) and IL-6 (r = 0.965). IL-12 (p40) showed also a positive correlation with IL-6 (r = 0.906). However, IL-10 showed a negative correlation with TNF-α (r = −0.915), IL-12(p40) (r = −0.790), and IL-6 (r = −0.902). In conclusion, TNF-α/IL-10 ratio may provide predictive information about outcome of encephalitic listeriosis in sheep.  相似文献   
3.
Lysophosphatidylcholine (LPC) and lysophosphatidic acid (LPA), the most prominent lysoglycerophospholipids, are emerging as a novel class of inflammatory lipids, joining thromboxanes, leukotrienes and prostaglandins with which they share metabolic pathways and regulatory mechanisms. Enzymes that participate in LPC and LPA metabolism, such as the phospholipase A2 superfamily (PLA2) and autotaxin (ATX, ENPP2), play central roles in regulating LPC and LPA levels and consequently their actions. LPC/LPA biosynthetic pathways will be briefly presented and LPC/LPA signaling properties and their possible functions in the regulation of the immune system and chronic inflammation will be reviewed. Furthermore, implications of exacerbated LPC and/or LPA signaling in the context of chronic inflammatory diseases, namely rheumatoid arthritis, multiple sclerosis, pulmonary fibrosis and hepatitis, will be discussed. This article is part of a Special Issue entitled Advances in Lysophospholipid Research.  相似文献   
4.
  总被引:4,自引:0,他引:4  
Granulocyte/macrophage colony-stimulatory factor (GM-CSF) is an attractive adjuvant for a DNA vaccine on account of its ability to recruit antigen-presenting cells (APCs) to the site of antigen synthesis as well as its ability to stimulate the maturation of dendritic cells (DCs). This study evaluated the utility of GM-CSF cDNA as a DNA vaccine adjuvant for glycoprotein B (gB) of pseudorabies virus (PrV) in a murine model. The co-injection of GM-CSF DNA enhanced the levels of serum PrV-specific IgG with a 1.5-to 2-fold increase. Moreover, GM-CSF co-injection inhibited the production of IgG2a isotype. However, it enhanced production of an IgG1 isotype resulting in humoral responses biased to the Th2-type against PrV antigen. In contrast, the co-administration of GM-CSF DNA enhanced the T cell-mediated immunity biased to the Th1-type, as judged by the significantly higher level of cytokine IL-2 and IFN-gamma production but not IL-4. When challenged with a lethal dose of PrV, the GM-CSF co-injection enhanced the resistance against a PrV infection. This suggests that co-inoculation with a vector expressing GM-CSF enhanced the protective immunity against a PrV infection. This immunity was caused by the induction of increased humoral and cellular immunity in response to PrV antigen.  相似文献   
5.
Alzheimer's disease (AD) is the most common form of dementia in the elderly and represents an important and increasing clinical challenge in terms of diagnosis and treatment. Mutations in the genes encoding amyloid precursor protein (APP), presenilin 1 (PSEN1) and presenilin 2 (PSEN2) are responsible for early-onset autosomal dominant AD. The ε4 allele of the apolipoprotein E (APOE) gene has been recognized as a major genetic risk factor for the more common, complex, late-onset AD. Fibrillar deposits by phosphorylated tau are also a key pathological feature of AD. The retromer complex also has been reported to late-onset AD. More recently, genome-wide association studies (GWASs) identified putative novel candidate genes associated with late-onset AD. Lastly, several studies showed that circulating microRNAs (miRNAs) in the cerebrospinal fluid (CSF) and blood serum of AD patients can be used as biomarkers in AD diagnosis. This review addresses the advances and challenges in determining genetic and diagnostic markers for complex AD pathogenesis.  相似文献   
6.
In addition to a remarkable sexual dimorphism of serum and urine proteomes, the rat is exceptional for the wide difference between the serum patterns during an acute phase reaction vs baseline conditions. This feature allows monitoring with high sensitivity onset and progression of any pathological state that involves an inflammatory component as well as assessing the outcome of any therapeutic intervention. Reference maps have been defined for the proteomes of serum, urine, cerebrospinal fluid and bronchoalveolar lavage fluid. For both serum and urine most of the proteomic investigations have dealt with toxicological testing, for BALF with allergic or irritative reactions, whereas with CSF the main aim was the characterization of rat models of neurological disorders. When surveying more than ten years of literature on rat biological fluid proteomics, it is puzzling to see how seldom a consistent analytical plan has been set up for the comparative investigation on two or more types of sample, whether to fully characterize a disease model or to evaluate pharmacological/toxicological effects of a drug. It is also regrettable that in several cases only a negligible part of the results is discussed at length whereas most data are not even made known to the scientific community.  相似文献   
7.
Recent studies suggest that NO and its reactive derivative peroxynitrite are implicated in the pathogenesis of multiple sclerosis (MS). Patients dying with MS demonstrate increased astrocytic inducible nitric oxide synthase activity, as well as increased levels of iNOS mRNA. Peroxynitrite is a strong oxidant capable of damaging target tissues, particularly the brain, which is known to be endowed with poor antioxidant buffering capacity. Inducible nitric oxide synthase is upregulated in the central nervous system (CNS) of animals with experimental allergic encephalomyelitis (EAE) and in patients with MS. We have recently demonstrated in patients with active MS a significant increase of NOS activity associated with increased nitration of proteins in the cerebrospinal fluid (CSF). Acetylcarnitine is proposed as a therapeutic agent for several neurodegenerative disorders. Accordingly, in the present study, MS patients were treated for 6 months with acetylcarnitine and compared with untreated MS subjects or with patients noninflammatory neurological conditions, taken as controls. Western blot analysis showed in MS patients increased nitrosative stress associated with a significant decrease of reduced glutathione (GSH). Increased levels of oxidized glutathione (GSSG) and nitrosothiols were also observed. Interestingly, treatment of MS patients with acetylcarnitine resulted in decreased CSF levels of NO reactive metabolites and protein nitration, as well as increased content of GSH and GSH/GSSG ratio. Our data sustain the hypothesis that nitrosative stress is a major consequence of NO produced in MS-affected CNS and implicate a possible important role for acetylcarnitine in protecting brain against nitrosative stress, which may underlie the pathogenesis of MS.  相似文献   
8.
以粒细胞巨噬细胞集落刺激因子(GMCSF) 为筛选文库的靶分子, 通过高效筛选(High throughputscreening, HTS) 方法来筛选多种多肽噬菌体文库, 在一个以噬菌体主要蛋白质为载体的多肽噬菌体文库中筛选到了一些与GMCSF结合的多肽, 并通过了ELISA和微淘选(micropanning) 实验的证实。这些多肽先导化合物经过进一步的优化, 可能成为GMCSF细胞因子的拮抗剂  相似文献   
9.
The chemokine receptor CXCR2 and its ligands are implicated in the progression of tumours and various inflammatory diseases. Activation of the CXCLs/CXCR2 axis activates multiple signalling pathways, including the PI3K, p38/ERK, and JAK pathways, and regulates cell survival and migration. The CXCLs/CXCR2 axis plays a vital role in the tumour microenvironment and in recruiting neutrophils to inflammatory sites. Extensive infiltration of neutrophils during chronic inflammation is one of the most important pathogenic factors in various inflammatory diseases. Chronic inflammation is considered to be closely correlated with initiation of cancer. In addition, immunosuppressive effects of myeloid-derived suppressor cells (MDSCs) against T cells attenuate the anti-tumour effects of T cells and promote tumour invasion and metastasis. Over the last several decades, many therapeutic strategies targeting CXCR2 have shown promising results and entered clinical trials. In this review, we focus on the features and functions of the CXCLs/CXCR2 axis and highlight its role in cancer and inflammatory diseases. We also discuss its potential use in targeted therapies.  相似文献   
10.
Zusammenfassung Zwischen und unter den Ependymzellen des Zentralkanals des Rückenmarkes vonCyprinus carpio kommen bipolare Nervenzellen vor. Der eine Fortsatz der Neurone (Liquorkontaktneurone) verläuft zwischen den Ependymzellen hindurch, tritt in den Canalis centralis ein und bildet im Liquor cerebrospinalis eine charakteristische Nervenendigung (Liquorkontakt-Nervenendigung). Diese besteht aus einem zentralen Körper und davon radiär ausstrahlenden zahlreichen Stereozilien, sowie einer Kinozilie. Ein direkter Kontakt zwischen den Liquorkontakt-Nervenendigungen und dem Reissnerschen Faden wurde nicht beobachtet. Der ependymofugale Fortsatz der Neurone hat Axonnatur. Im Perikaryon der Nervenzellen findet man endoplasmatisches Retikulum mit glatter und rauher Oberfläche, freie Ribosomen, Golgi-Areale, sowie Mitochondrien und granulierte Vesikel (Durchmesser 700–1000 Å). Axone, die synaptische und granulierte Bläschen (Durchmesser 700–1000 Å) enthalten, bilden mit den Perikaryen und den zum Zentralkanal verlaufenden Nervenfortsätzen Synapsen. Auf den Ependymzellen konnten stellenweise atypische Zilien beobachtet werden. Der Vergleich der bisher untersuchten Tierarten zeigt, daß die Struktur der spinalen Liquorkontaktneurone von den Fischen bis zu den Säugern prinzipiell gleichartig ist.
Ultrastructure of the CSF contacting neurons of the central canal of the spinal cord in the carp (Cyprinus carpio)
Summary Bipolar nerve cells are situated between and below the ependymal cells of the central canal of the spinal cord ofCyprinus carpio. One of the processes of the neurons (CSF contacting neurons) passes by between the ependymal cells into the central canal and forms there a characteristic nerve ending in the cerebrospinal fluid (CSF contacting nerve ending). These terminals consist of a central body with numerous stereocilia and one kinocilium. We could not observe any direct contact between the CSF contacting nerve endings and Reissner's fibre. The ependymofugal process of the nerve cells is axon-like. In the perikarya of the CSF contacting neurons, dense-core vesicles (diameter 700–1000 Å) are found besides of smooth and rough-surfaced endoplasmic reticulum, free ribosomes, Golgi areas and mitochondria. Axons containing synaptic and granulated vesicles (diameter 700–1000 Å), form synapses with the perikarya and the CSF contacting nerve processes. On the surface of single ependymal cells, atypical cilia could be observed. The comparison of the species studied up to now, shows that the structure of the spinal CSF contacting neurons is principally similar from fishes up to mammals.
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