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1.
The present study was designed to assess whether the visibility of ones’ own exploratory movements impairs or enhances perceptual speed and precision of haptic stimuli with varying complexity. Previous studies have shown that noninformative vision of steady surroundings improves haptic spatial perception. However, due to the serial nature of haptic processing and limited capacity of working memory resources, we hypothesized that noninformative vision of limb movements may impair haptic perception. The study sample consisted of ninety-eight healthy adults who were randomized into two groups, matched for sex and age. Participants were required to explore two-dimensional haptic stimuli with varying complexity and to recognize them visually. The difference between the two experimental groups was a screen that would prevent the participants from viewing their hands during exploration in the nonobservation condition (NonOb). The other half of participants were able to see their hands in the manual movement observation condition (MovOb) thanks to the special design of the stimuli. As hypothesized, the persons in the MovOb condition made significantly more errors. The difference in error frequency between participants of the MovOb and NonOb condition was greater for complex stimuli than for simple ones. These results suggest that incoming visual information about own manual exploration movements increases competitive pressure for limited working memory resources, and therefore, more recognition errors are made. Covering the hands during exploration may constitute a helpful simplification of the task’s demands by supporting the maintenance of information in working memory. Additionally, the relation of haptic complexity and stimulus characteristics was analyzed.  相似文献   
2.
A bull aged 16 months with bilateral testicular hypoplasia and azoospermia was persistently infected with bovine viral diarrhoea virus (BVDV). Viral antigen was detected in serum and semen by ELISA, but the animal was serologically negative. After slaughter, the genital tract was examined histopathologically and by immunohistochemistry, including double immunolabelling with BVDV antibody and either S-100 antibody (for Sertoli cells) or ferritin antibody (for Leydig cells). The seminiferous tubules of both testes were lined by a single layer of Sertoli cells and the germinal epithelium was completely absent except for a few remaining spermatogonia. BVDV antigen was demonstrated (1) in the media of arterial vessel walls of the testis, epididymis, urethra, prostate, and vesicular and bulbourethral glands, (2) in epithelial cells of the ductus epididymidis, the accessory glands and the urethra, and (3) in the testis, mainly in Sertoli cells and to a lesser extent in the spermatogonia that remained, but not in Leydig cells. The testicular hypoplasia was possibly linked to the BVDV infection.  相似文献   
3.
Patients presenting late in the course of kidney disease who require urgent initiation of dialysis have traditionally received temporary vascular catheters followed by hemodialysis. Recent changes in Medicare payment policy for dialysis in the USA incentivized the use of peritoneal dialysis (PD). Consequently, the use of more expeditious PD for late-presenting patients (urgent-start PD) has received new attention. Urgent-start PD has been shown to be safe and effective, and offers a mechanism for increasing PD utilization. However, there has been no assessment of the dialysis-related costs over the first 90 days of care.The objective of this study was to characterize the costs associated with urgent-start PD, urgent-start hemodialysis (HD), or a dual approach (urgent-start HD followed by urgent-start PD) over the first 90 days of treatment from a provider perspective.A survey of practitioners from 5 clinics known to use urgent-start PD was conducted to provide inputs for a cost model representing typical patients. Model inputs were obtained from the survey, literature review, and available cost data. Sensitivity analyses were also conducted.The estimated per patient cost over the first 90 days for urgent-start PD was $16,398. Dialysis access represented 15% of total costs, dialysis services 48%, and initial hospitalization 37%. For urgent-start HD, total per patient costs were $19,352, and dialysis access accounted for 27%, dialysis services 42%, and initial hospitalization 31%. The estimated cost for dual patients was $19,400.Urgent-start PD may offer a cost saving approach for the initiation of dialysis in eligible patients requiring an urgent-start to dialysis.  相似文献   
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The role of proinflammatory cytokines in the response to acute stressor exposure has received recent attention. Exposure to a single session of inescapable shock (IS) induces peripheral and central proinflammatory cytokines. Other stressors also increase expression of proinflammatory cytokine mRNA and/or protein in various tissues. However, the induction of central and peripheral proinflammatory cytokines by stressors remains controversial and the pattern of cytokine induction is not consistent across stressors. The present experiments sought to examine the pattern of the proinflammatory cytokine response to a stressor known to cause elevations of IL-1beta protein. mRNA expression for three proinflammatory cytokines, IL-1beta, TNF-alpha and IL-6, and IL-1beta protein was examined after IS. IS increases IL-1beta mRNA and/or protein in a variety of tissues, including hypothalamus, hippocampus, pituitary and spleen. Furthermore, IS concomitantly alters IL-1beta mRNA and protein in hypothalamus and spleen, while the IL-1beta mRNA increase in pituitary lags behind the increase of IL-1beta protein. Interestingly, IL-1beta mRNA is elevated in hippocampus 4 h after IS, but an increase of IL-1beta protein in hippocampus is not detected. Expression of TNF-alpha and IL-6 mRNA do not increase in response to IS. Indeed, TNF-alpha mRNA expression decreases in cortex, pituitary and liver immediately after IS. These findings suggest that alterations of proinflammatory cytokine expression by stressors, and IS in particular, are region- and cytokine-specific.  相似文献   
6.
This survey explored how fifth-grade Mexican premenarcheal girls (N = 80) and their teachers (N = 16) view the preparation students receive about menstruation at school. The most discussed topics in class included hygiene and body functions. The main discrepancies between girls and teachers were as follows: (a) more teachers than girls reported that they discussed the emotional aspects of menses, (b) teachers indicated that their pupils were better prepared than the students themselves believed. (c) more teachers reported that the girls acted ashamed during the classes, and (d) more girls perceived that boys behaved in a mocking manner, whereas more teachers thought that the boys acted nervous. In conclusion, teaching about menstruation is problematic, but these findings provide information for teachers to meet the needs of girls more efficiently.  相似文献   
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8.
Opioid-induced proinflammatory glial activation modulates wide-ranging aspects of opioid pharmacology including: opposition of acute and chronic opioid analgesia, opioid analgesic tolerance, opioid-induced hyperalgesia, development of opioid dependence, opioid reward, and opioid respiratory depression. However, the mechanism(s) contributing to opioid-induced proinflammatory actions remains unresolved. The potential involvement of toll-like receptor 4 (TLR4) was examined using in vitro, in vivo, and in silico techniques. Morphine non-stereoselectively induced TLR4 signaling in vitro, blocked by a classical TLR4 antagonist and non-stereoselectively by naloxone. Pharmacological blockade of TLR4 signaling in vivo potentiated acute intrathecal morphine analgesia, attenuated development of analgesic tolerance, hyperalgesia, and opioid withdrawal behaviors. TLR4 opposition to opioid actions was supported by morphine treatment of TLR4 knockout mice, which revealed a significant threefold leftward shift in the analgesia dose response function, versus wildtype mice. A range of structurally diverse clinically-employed opioid analgesics was found to be capable of activating TLR4 signaling in vitro. Selectivity in the response was identified since morphine-3-glucuronide, a morphine metabolite with no opioid receptor activity, displayed significant TLR4 activity, whilst the opioid receptor active metabolite, morphine-6-glucuronide, was devoid of such properties. In silico docking simulations revealed ligands bound preferentially to the LPS binding pocket of MD-2 rather than TLR4. An in silico to in vitro prediction model was built and tested with substantial accuracy. These data provide evidence that select opioids may non-stereoselectively influence TLR4 signaling and have behavioral consequences resulting, in part, via TLR4 signaling.  相似文献   
9.
Spinal proinflammatory cytokines are powerful pain-enhancing signals that contribute to pain following peripheral nerve injury (neuropathic pain). Recently, one proinflammatory cytokine, interleukin-1, was also implicated in the loss of analgesia upon repeated morphine exposure (tolerance). In contrast to prior literature, we demonstrate that the action of several spinal proinflammatory cytokines oppose systemic and intrathecal opioid analgesia, causing reduced pain suppression. In vitro morphine exposure of lumbar dorsal spinal cord caused significant increases in proinflammatory cytokine and chemokine release. Opposition of analgesia by proinflammatory cytokines is rapid, occurring 5 min after intrathecal (perispinal) opioid administration. We document that opposition of analgesia by proinflammatory cytokines cannot be accounted for by an alteration in spinal morphine concentrations. The acute anti-analgesic effects of proinflammatory cytokines occur in a p38 mitogen-activated protein kinase and nitric oxide dependent fashion. Chronic intrathecal morphine or methadone significantly increased spinal glial activation (toll-like receptor 4 mRNA and protein) and the expression of multiple chemokines and cytokines, combined with development of analgesic tolerance and pain enhancement (hyperalgesia, allodynia). Statistical analysis demonstrated that a cluster of cytokines and chemokines was linked with pain-related behavioral changes. Moreover, blockade of spinal proinflammatory cytokines during a stringent morphine regimen previously associated with altered neuronal function also attenuated enhanced pain, supportive that proinflammatory cytokines are importantly involved in tolerance induced by such regimens. These data implicate multiple opioid-induced spinal proinflammatory cytokines in opposing both acute and chronic opioid analgesia, and provide a novel mechanism for the opposition of acute opioid analgesia.  相似文献   
10.

Aim

Interleukin (IL)-10 and IL-12 contribute to immune responses against hepatitis B virus (HBV) infection. Polymorphisms in the IL-10 and IL-12A genes might affect the clinical outcome of HBV infection. We evaluated the association of IL-10 rs1800896 and rs3024490, and IL-12A rs568408 and rs2243115 with the progression of HBV infection and development of severe liver disease stages in a white European population.

Method

A total of 636 white European patients with chronic HBV infection, 239 individuals with spontaneous HBV surface antigen seroclearance, and 254 healthy controls were enrolled. The chronic HBV infection group included patients with hepatitis B envelope antigen (HBeAg) negative chronic hepatitis B (n = 255), with HBeAg positive chronic hepatitis B (n = 99) and with HBeAg negative HBV infection (n = 228). A total of 104 chronically infected patients were diagnosed with liver cirrhosis. Serum levels of cytokines were measured in patients with HBV infection (n = 195) and in healthy controls (n = 160).

Results

In adjusted multivariate analysis, the IL-10 rs1800896 AG/GG genotypes were significantly associated with an increased probability of HBV surface antigen seroclearance (OR = 1.75, 95% CI 1.04–2.94, p = 0.034), with an increased likelihood of HBeAg negative chronic infection (OR = 1.93, 95% CI 1.05–3.54, p = 0.034) and with increased serum cytokines levels in female patients. In contrast, the IL-12A rs568408 AG/AA genotypes were independently associated with an increased risk to develop liver cirrhosis, with an OR of 1.90 (95% CI 1.07–3.39, p = 0.029) in male patients.

Conclusion

The current study shows a sex-related association of the IL-10 single-nucleotide polymorphism rs1800896 and IL-12A single-nucleotide polymorphism rs568408 with different stages of HBV infection and with HBV-related liver cirrhosis in white European patients.  相似文献   
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