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111.
Mori Y  Otsuki N  Sakata M  Okamoto K 《Uirusu》2011,61(2):211-219
Many pathogens important for medicine, veterinary medicine or public health belong to the genera alphavirus and rubivirus within the family Togaviridae. 29 species of alphaviruses have been reported, and most of them are arboviruses. Chikungnya virus re-emerged in Kenya in 2004 and the epidemics spread to the Indian Ocean islands and many countries in South Asia, South-East Asia and Europe. On the other hand, rubella virus, a sole member of the genus rubivirus, is the causative agent of rubella and congenital rubella syndrome (CRS). Because human is only a natural host of the virus and effective live attenuated vaccines are available, immunization activities are strengthened globally to eliminate rubella and CRS, together with measles.  相似文献   
112.
Four glycine-rich protein (GRP) genes were identified from expressed sequence tags of the maxillary galea of the silkworm. All four genes were expressed in the maxillary pulp, antenna, labrum, and labium, but none of the genes were expressed in most internal organs. Expression of one of the genes, termed bmSIGRP, was further increased approximately fivefold in the mouth region (including the maxilla, antenna, labrum, labium, and mandible) after 24 h of starvation. bmSIGRP expression peaked at 24 h and gradually declined during the subsequent 2 days. When a synthetic diet not containing proteins was fed, bmSIGRP expression increased significantly in the mouth region to levels similar to that observed in starved larvae. Synthetic diets that lacked vitamins or salts but contained amino acids did not significantly affect bmSIGRP expression. These results suggest that amino acid depletion increases bmSIGRP expression.  相似文献   
113.

Background

Cognitive impairment could affect quality of life for patients with multiple sclerosis (MS), and cognitive function may be correlated with several factors such as depression and fatigue. This study aimed to evaluate cognitive function in Japanese patients with MS and the association between cognitive function and apathy, fatigue, and depression.

Methods

The Brief Repeatable Battery of Neuropsychological tests (BRB-N) was performed in 184 Japanese patients with MS and 163 healthy controls matched for age, gender, and education. The Apathy Scale (AS), Fatigue Questionnaire (FQ), and Beck Depression Inventory Second Edition (BDI-II) were used to evaluate apathy, fatigue, and depression, respectively. Student’s t-test was used to compare MS patients and healthy controls. Correlations between two factors were assessed using the Pearson correlation test, and multiple regression analysis was used to evaluate how much each factor affected the BRB-N score.

Results

In all BRB-N tests, patients with MS scored significantly lower than controls, and the effect size of symbol digit modalities test was the highest among the 9 tests of the BRB-N. Patients with MS had higher AS (p?<?0.001), FQ (p?<?0.0001), and BDI-II (p?<?0.0001) scores than controls. In patients with MS, scores on most of the BRB-N tests correlated with scores on the AS and BDI-II; however, there was little correlation between scores on the BRB-N tests and those on the FQ.

Conclusions

Cognitive function was impaired, particularly information-processing speed, and decreased cognitive function was correlated with apathy and depression in Japanese patients with MS. Despite the association between cognitive variables and depression/apathy, cognitive function was impaired beyond the effect of depression and apathy. However, subjective fatigue is not related with cognitive impairment. Taken together, this suggests that different therapeutic approaches are needed to improve subjective fatigue and cognition, and thereby quality of life, in patients with MS.  相似文献   
114.
To examine the role of matrix proteins in the formation of gouty tophus, we analyzed the crystalline components and matrix proteins in a gouty tophus from a patient with recurrent gout. Micro-area X-ray diffraction analysis and infrared spectroscopy indicated that the tophus was composed of monosodium urate monohydrate. Proteomic analysis identified 134 proteins from the tophus as matrix proteins. Many proteins relevant to inflammation and host defense were identified, and immunoglobulin was detected in all four extracted fractions (KCl, formic acid, guanidine-HCl, and ethylenediaminetetraacetic acid) and from many spots throughout a broad molecular weight range after electrophoresis. It is thought that the process of biological defense including the immunity has occurred in the gouty tophus.  相似文献   
115.
Mycoplasmas, a group of small parasitic bacteria, adhere to and move across host cell surfaces. The role of motility across host cell surfaces in pathogenesis remains unclear. Here, we used optical microscopy to visualize rheotactic behavior in three phylogenetically distant species of Mycoplasma using a microfluidic chamber that enabled the application of precisely controlled fluid flow. We show that directional movements against fluid flow occur synchronously with the polarized cell orienting itself to be parallel against the direction of flow. Analysis of depolarized cells revealed that morphology itself functions as a sensor to recognize rheological properties that mimic those found on host-cell surfaces. These results demonstrate the vital role of cell morphology and motility in responding to mechanical forces encountered in the native environment.  相似文献   
116.
Corticotropin-releasing factor (CRF) and both human pancreatic growth hormone-releasing factor (hp-GRF) and rat hypothalamic GRF (rh-GRF) stimulated ACTH release from neoplastic AtT-20 mouse pituitary tumor cells in a dose-dependent fashion, with CRF inducing a 10-fold increase and GRF a maximal increment of approximately one-half that of CRF. Neither rh-GRF nor hp-GRF induced ACTH release in normal anterior pituitary cells. Pretreatment with either dexamethasone or somatostatin prior to the addition of rh-GRF inhibited the increase in ACTH release. Both ovine CRF and rh-GRF stimulated adenosine 3,5-monophosphate production in AtT-20 cells. The weak but clearly discernible effect of GRF on ACTH release from AtT-20 cells may be due to an abnormality in the AtT-20 cell receptor.  相似文献   
117.
Studies of phenotypic variation in nature often consider only a single potential selective agent. In such cases, it remains an open question as to whether variation attributed to that single measured agent might be influenced by some other unmeasured agent. Previous research has shown that phenotypic variation in the Trinidadian guppy (Poecilia reticulata) is strongly influenced by predation regime, and we here ask whether parasitism might represent an additional important selective agent shaping this variation. We performed a field survey of 26 natural guppy populations of known predation regime in northern Trinidad. We quantified levels of parasitism of guppies by the monogenean ecotoparasite, Gyrodactylus, and examined whether this parasite was associated with guppy body size or male colour. Spatial variation in Gyrodactylus parasitism was consistent between years, and parasite prevalence was generally, but not always, higher at high-predation sites than at low-predation sites. Consistent with previous work, predation regime was related to guppy size and some aspects of male colour, whereas parasitism showed few and only minor associations with the same traits. Moreover, a consideration of parasitism did not alter any interpretations regarding associations between guppy traits and predation regimes. These results suggest that parasitism, at least as quantified in the present study, does not play a major role in shaping variation in guppy body size or colour. Nevertheless, considerable variation in these traits, even within a predation regime, suggests the likely importance of other selective agents beyond just predation regime.  相似文献   
118.
Heat shock proteins (HSPs) induced by brain ischemia may play an important role in neuroprotection from neuronal degeneration. In this study, we examined the cerebral blood flow (CBF) threshold to produce regional differences in HSP72 induction after transient forebrain ischemia in spontaneously hypertensive rats (SHRs). Female SHRs were subjected to 20 min of cerebral ischemia induced by bilateral carotid artery occlusion. The CBF was measured by laser Doppler flowmetry. At forty-eight hours after cerebral ischemia and reperfusion, the rats were decapitated and the brains were removed. Specific areas (hippocampal CA1, CA2-3, dentate gyrus, dorsolateral and ventromedial striatum, and parietal cortex) were thereafter dissected from the brain. The amounts of HSP72 in these samples were determined using Western blot analysis. In the hippocampus, HSP72 was induced when the CBF decreased to less than 18–25% of the resting level. The mean values of HSP72 produced in the CA1 area, CA2-3 area, and the dentate gyrus following ischemia and reperfusion treatment were 4.44 ± 1.43 (±SD) ng/g prtein, 3.51 ± 0.72 ng/g protein and 3.77 ± 1.05 ng/g protein, respectively. In the parietal cortex, the amount of HSP72 induction was less pronounced (2.55 ± 0.40 ng/g protein), while HSP72 was hardly detected at all in the striatum, even under conditions of very severe CBF reduction and reperfusion. We demonstrated the existence of both a CBF threshold (i.e., approximately 20% of the resting level) for HSP72 induction and regional heterogeneity for the induction of HSP72 protein.  相似文献   
119.
Recent progress in genome-based breeding has created various fish strains carrying desirable genetic traits; however, methods for the long-term preservation of their genetic resources have not yet been developed, mainly due to the lack of cryopreservation techniques for fish eggs and embryos. Recently, we established an alternative cryopreservation technique for fish spermatogonia using a slow-freezing method. Furthermore, we developed a transplantation system to produce functional eggs and sperm derived from spermatogonia. Spermatogonia isolated from the testes of vasa-green fluorescent protein (Gfp) transgenic rainbow trout (Oncorhynchus mykiss) were transplanted into the peritoneal cavity of triploid masu salmon (Oncorhynchus masou) hatchlings of both genders. The transplanted trout spermatogonia migrated towards the gonadal anlagen of the recipient salmon, into which they were subsequently incorporated. We confirmed that the donor-derived spermatogonia resumed gametogenesis, and produced sperm and eggs in male and female recipient salmon, respectively. Fertilization of the resultant eggs and sperm produced only rainbow trout in the first filial (F1) generation, suggesting that the sterile triploid recipient salmon produced functional eggs and sperm derived from the trout donors. A combination of spermatogonial transplantation and cryopreservation could be a powerful tool for preserving valuable fish strains with desirable genetic traits and endangered species.  相似文献   
120.
Recombinant Glutathione S-transferase of Haemaphysalis longicornis (rGST-Hl) was expressed in Escherichia coli, purified by affinity chromatography and used in the immunization of cattle. Western blot analysis showed positive antibody response in cattle immunized with rGST-Hl. The tests also showed that immunized bovine sera recognize native Rhipicephalus microplus proteins in different tissue extracts. Furthermore, the vaccine potential of rGST-Hl was investigated against infestation of Hereford cattle by R. microplus. Vaccination of cattle with rGST-Hl conferred partial cross-protection immunity against R. microplus. Considering the effect on number of engorged ticks, egg laying capacity and egg fertility, the overall efficacy of vaccination was of 57%, as compared with control group.  相似文献   
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