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31.
Highlights? Tmem64-deficient mice show increased bone volume ? Tmem64 deficiency reduces [Ca2+]i oscillation in response to RANKL stimulation ? Tmem64 interacts with SERCA2 ? Tmem64 positively regulates osteoclast formation via SERCA2/Ca2+ signaling  相似文献   
32.
Saffold virus (SAFV) was identified as a human cardiovirus in 2007. Although several epidemiological studies have been reported, they have failed to provide a clear picture of the relationship between SAFV and human diseases. SAFV genotype 3 has been isolated from the cerebrospinal fluid specimen of patient with aseptic meningitis. This finding is of interest since Theiler’s murine encephalomyelitis virus (TMEV), which is the closely related virus, is known to cause a multiple sclerosis-like syndrome in mice. TMEV persistently infects in mouse macrophage cells in vivo and in vitro, and the viral persistence is essential in TMEV-induced demyelinating disease. The precise mechanism(s) of SAFV infection still remain unclear. In order to clarify the SAFV pathogenicity, in the present study, we studied the possibilities of the in vitro persistent infection of SAFV. The two distinct phenotypes of HeLa cells, HeLa-N and HeLa-R, were identified. In these cells, the type of SAFV-3 infection was clearly different. HeLa-N cells were lyticly infected with SAFV-3 and the host suitable for the efficient growth. On the other hand, HeLa-R cells were persistently infected with SAFV-3. In addition, the SAFV persistence in HeLa-R cells is independent of type I IFN response of host cells although the TMEV persistence in mouse macrophage cells depends on the response. Furthermore, it was suggested that SAFV persistence may be influenced by the expression of receptor(s) for SAFV infection on the host cells. The present findings on SAFV persistence will provide the important information to encourage the research of SAFV pathogenicity.  相似文献   
33.
Previous studies indicated that empty time intervals are better discriminated in the auditory than in the visual modality, and when delimited by signals delivered from the same (intramodal intervals) rather than from different sensory modalities (intermodal intervals). The present electrophysiological study was conducted to determine the mechanisms which modulated the performances in inter- and intramodal conditions. Participants were asked to categorise as short or long empty intervals marked by auditory (A) and/or visual (V) signals (intramodal intervals: AA, VV; intermodal intervals: AV, VA). Behavioural data revealed that the performances were higher for the AA intervals than for the three other intervals and lower for inter- compared to intramodal intervals. Electrophysiological results indicated that the CNV amplitude recorded at fronto-central electrodes increased significantly until the end of the presentation of the long intervals in the AA conditions, while no significant change in the time course of this component was observed for the other three modalities of presentation. They also indicated that the N1 and P2 amplitudes recorded after the presentation of the signals which delimited the beginning of the intervals were higher for the inter- (AV/VA) compared to the intramodal intervals (AA/VV). The time course of the CNV revealed that the high performances observed with AA intervals would be related to the effectiveness of the neural mechanisms underlying the processing of the ongoing interval. The greater amplitude of the N1 and P2 components during the intermodal intervals suggests that the weak performances observed in these conditions would be caused by an attentional bias induced by the cognitive load and the necessity to switch between modalities.  相似文献   
34.

Objective

To assess the separate effects of thumb and finger extension/flexion on median nerve position and cross-sectional area.

Methods

Ultrasonography was used to assess median nerve transverse position and cross-sectional area within the carpal tunnel at rest and its movement during volitional flexion of the individual digits of the hand. Both wrists of 165 normal subjects (11 men, 4 women, mean age, 28.6, range, 22 to 38) were studied.

Results

Thumb flexion resulted in transverse movement of the median nerve in radial direction (1.2±0.6 mm), whereas flexion of the fingers produced transverse movement in ulnar direction, which was most pronounced during flexion of the index and middle fingers (3.2±0.9 and 3.1±1.0 mm, respectively). Lesser but still statistically significant movements were noted with flexion of the ring finger (2.0±0.8 mm) and little finger (1.2±0.5 mm). Flexion of the thumb or individual fingers did not change median nerve cross-sectional area (8.5±1.1 mm2).

Conclusions

Volitional flexion of the thumb and individual fingers, particularly the index and middle fingers, produced significant transverse movement of the median nerve within the carpal tunnel but did not alter the cross-sectional area of the nerve. The importance of these findings on the understanding of the pathogenesis of the carpal tunnel syndrome and its treatment remains to be investigated.  相似文献   
35.
Type I IFNs are a range of host-derived molecules with adjuvant potential; they have been used for many years in the treatment of cancer and viral hepatitis. Therefore, the safety of IFNs for human use has been established. In this study, we evaluated the mucosal adjuvanticity of IFN-β administered intranasally to mice with diphtheria toxoid, and suggested a method to improve its adjuvanticity. When IFN-β alone was used as a mucosal adjuvant, no clear results were obtained. However, simultaneous administration of IFN-β and chitosan resulted in an enhancement of the specific serum immunoglobulin G (IgG) and IgA antibody responses, the mucosal IgA antibody response, and antitoxin titers. Furthermore, the intranasal administration of IFN-α alone resulted in a greater increase in antibody titer than IFN-β, and a synergistic effect with chitosan was also observed. These findings suggest that intranasal administration of chitosan and Type I IFNs may display an effective synergistic mucosal adjuvant activity.  相似文献   
36.
Applied Entomology and Zoology - To evaluate the infection risk of Anoplophora malasiaca (Thomson) (Coleoptera: Cerambycidae) in two species of Japanese pine bonsais (Japanese black pine and...  相似文献   
37.
GB virus C (GBV‐C), a human virus of the Flaviviridae family that is structurally and epidemiologically closest to hepatitis C virus (HCV), has been reported to confer beneficial outcomes in HIV‐positive patients. However, the prevalence of GBV‐C in HIV‐positive individuals in Indonesia is unknown. Since GBV‐C is more prevalent in anti‐HCV positive patients than in anti‐HCV negative subjects, transmission of GBV‐C and HCV could be by the same method. This study examined the prevalence and molecular characteristics of GBV‐C infection in HIV patients in Yogyakarta, Indonesia. The prevalence of GBV‐C among HIV patients (n = 125, median age 31 years) based on the 5′UTR region was 111/125 (88.8%), including 39/48 (81.3%) and 72/77 (93.5%) HIV‐infected patients with and without HCV infection, respectively. GBV‐C isolates were of genotype 2a, 3 and 6 in 58.3%, 12.6% and 28.4% of patients, respectively. Patients with genotype 3 were significantly younger than those with genotypes 2a or 6 (P = 0.001 and P = 0.012, respectively). Genotypes 3 and 6 were significantly associated with injection drug use (P = 0.004 and P = 0.002, respectively) and HCV co‐infection (P < 0.001 for both genotypes), indicating a shared transmission route with HCV. In conclusion, the prevalence of GBV‐C among HIV‐positive patients in Indonesia is high, and three genotypes were detected, namely genotype 2a, 3 and 6.  相似文献   
38.
We proposed that cortical organization for the execution of adequate licking in cats was processed under the control of two kinds of affiliated groups for face and jaw & tongue movements (Hiraba H, Sato T. 2005A. Cerebral control of face, jaw, and tongue movements in awake cats: Changes in regional cerebral blood flow during lateral feeding Somatosens Mot Res 22:307–317). We assumed the cortical organization for face movements from changes in MRN (mastication-related neuron) activities recorded at area M (motor cortex) and orofacial behaviors after the lesion in the facial SI (facial region in the primary somatosensory cortex). Although we showed the relationship between facial SI (area 3b) and area M (area 4δ), the property of area C (area 3a) was not fully described. The aim of this present study is to investigate the functional role of area C (the anterior part of the coronal sulcus) that transfers somatosensory information in facial SI to area M, as shown in a previous paper (Hiraba H. 2004. The function of sensory information from the first somatosensory cortex for facial movements during ingestion in cats Somatosens Mot Res 21:87--97). We examined the properties of MRNs in area C and changes in orofacial behaviors after the area C or area M lesion. MRNs in area C had in common RFs in the lingual, perioral, and mandibular parts, and activity patterns of MRNs showed both post- and pre-movement types. Furthermore, cats with the area C lesion showed similar disorders to cats with the area M lesion, such as the dropping of food from the contralateral mouth, prolongation of the period of ingestion and mastication, and so on. From these results, we believe firmly the organization of unilateral cortical processing in facial SI, area C, and area M for face movements during licking.  相似文献   
39.
In a previous paper (Hiraba and Sato ) we reported that an accurate mastication might be executed by the cortical processing in bilateral masticatory area (MA)and motor cortices. The aim of this study was to determine if cats with lesion of either unilateral or bilateral MA showed changes in mastication. After exploring mechanoreceptive fields and motor effects of mastication-related neurons (MRNs) in MA using the single unit recording and intracortical microstimulation methods, we made various lesions in MAs with injections of kainic acid (0.1%, 2.0?µl). Since the MA was divided into facial (F) and intraoral (I) projection areas as reported in the previous paper, cats with the unilateral lesion in F or I, and with the bilateral lesion in F & F, I & I or F & I (F on one side and I on other side) were prepared. Cats with unilateral lesion in F or I and with bilateral lesion in F & I showed no changes in mastication except for prolongation of the food intake and masticatory periods. Cats with bilateral lesion into F & F, or I & I showed wider jaw-opening during mastication. Particularly, the latter group showed enormous jaw-opening, delay in the start of mastication and difficulty in manipulating food on the tongue. In all cats with lesions of each type, masticatory and swallowing rhythms remained normal. These findings suggest that accurate mastication is executed by the close integration between F & F and I & I of the bilateral MA.  相似文献   
40.
Several epidemiological and preclinical studies suggest that non‐steroidal anti‐inflammatory drugs (NSAIDs), which inhibit cyclooxygenase (COX), reduce the risk of Alzheimer's disease (AD) and can lower β‐amyloid (Aβ) production and inhibit neuroinflammation. However, follow‐up clinical trials, mostly using selective cyclooxygenase (COX)‐2 inhibitors, failed to show any beneficial effect in AD patients with mild to severe cognitive deficits. Recent data indicated that COX‐1, classically viewed as the homeostatic isoform, is localized in microglia and is actively involved in brain injury induced by pro‐inflammatory stimuli including Aβ, lipopolysaccharide, and interleukins. We hypothesized that neuroinflammation is critical for disease progression and selective COX‐1 inhibition, rather than COX‐2 inhibition, can reduce neuroinflammation and AD pathology. Here, we show that treatment of 20‐month‐old triple transgenic AD (3 × Tg‐AD) mice with the COX‐1 selective inhibitor SC‐560 improved spatial learning and memory, and reduced amyloid deposits and tau hyperphosphorylation. SC‐560 also reduced glial activation and brain expression of inflammatory markers in 3 × Tg‐AD mice, and switched the activated microglia phenotype promoting their phagocytic ability. The present findings are the first to demonstrate that selective COX‐1 inhibition reduces neuroinflammation, neuropathology, and improves cognitive function in 3 × Tg‐AD mice. Thus, selective COX‐1 inhibition should be further investigated as a potential therapeutic approach for AD.  相似文献   
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