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61.
Cell-mediated memory immune responses to viral antigens are important for protection against viruses causing persistent or acute infections. This study compared the cytokine profile of memory T-helper cells specific for cytomegalovirus (CMV) in healthy CMV-seropositive men and women. The cytokine response reflected T(H)1 bias, with dominant secretion of interferon (IFN)-gamma along with moderate levels of tumor necrosis factor-alpha, interleukin (IL)-10, and IL-2. Analyzed by gender, women had higher and significant spontaneous release of IFN-gamma and CMV-specific IL-2 secretion. Similar analysis with herpes simplex virus-1 showed a trend toward higher cytokine responsiveness in women, but the differences were not statistically significant. In contrast, men had statistically significant higher influenza virus-specific tumor necrosis factor-alpha secretion. IL-4 and IL-5, both T(H)2 cytokines, were low for all three viruses. The results show a predominant T(H)1 antiviral cytokine T-help memory response with significant differences linked to gender. Such differences may have an impact in the design of immunization strategies against CMV.  相似文献   
62.
Pathology and Immunocytochemistry of a Kuru Brain   总被引:1,自引:0,他引:1  
We report here results of modern staining techniques including anti-prion protein (PrP) immunocytochemistry to a set of archival brain specimens of a 16 year-old male who died from kuru in 1967. Brain suspensions transmitted disease to chimpanzees and New World monkeys. The PrP gene is homozygous for valine at the polymorphic codon 129. Histology shows neuronal loss, spongiform change, and astrogliosis. Lesions are maximal in parasagittal and interhemispheric areas of frontal, central and parietal cortex, cingulate cortex, striatum, and thalamus, and are accentuated in middle and deep cerebral cortical layers. PrP accumulates as diffuse synaptic type deposits and mostly unicentric plaques. PrP deposition is maximal in parasagittal and interhemispheric areas of frontal, central and parietal cortex, cingulate cortex, basal ganglia, and cerebellar cortex. Plaques are prominent in the striatum, thalamus, and granular layer of cerebellar cortex. Meticulous examination reveals only rare "florid" plaques with surrounding vacuolation.
We conclude that 1) pathology including immunomorphology of PrP deposition in this kuru brain is within the lesion spectrum of Creutzfeldt-Jakob disease although plaques are unusually prominent and widespread; 2) kuru does not share the neuropathological hallmarks of the new Creutzfeldt-Jakob disease variant recently reported in the UK and France; 3) topographic prominence of PrP deposition parallels that of spongiform change and/or astrogliosis.  相似文献   
63.
We examined the effectiveness of 33 U.S.-based HIV intervention studies in reducing the sexual risk behaviors of drug users by reducing unprotected sex or increasing the use of male condoms. The studies, identified as of June 1998, through the HIV/AIDS Prevention Research Synthesis project, were published in 1988 or later, measured behavioral or biologic outcomes, used experimental designs or certain quasi-experimental designs, and reported sufficient data for calculating an effect size for sexual risk reduction. Of the 33 studies, 94% recruited injection drug users; 21% recruited crack users. The mean age of participants was 36 years. Almost all studies were randomized (94%), provided another HIV intervention to the comparison groups (91%), and evaluated behavioral interventions (91%). On average, interventions were conducted in 5 sessions (total, 10 hours) during 4.5 months. Interventions compared with no interventions were strong and significant (k = 3; odds ratio [OR], 0.60; 95% confidence interval [CI], 0.43-0.85). Interventions compared with other HIV interventions showed a modest additional benefit (k = 30; OR, 0.91; 95% CI, 0.81-1.03). When we extrapolated our result (an OR of 0.60) to a population with a 72% prevalence of risk behavior, the proportion of drug users who reduced their risk behaviors was 12.6% greater in the intervention groups than in the comparison groups. Our meta-analysis shows that interventions can lead to sexual risk reduction among drug users and justifies providing interventions to drug users. Developing interventions with stronger effects to further reduce sexual risk behaviors among drug users must remain a high priority.  相似文献   
64.
BACKGROUND: Anxious depression, defined as Major Depressive Disorder (MDD) with high levels of anxiety symptoms, may represent a relatively common depressive subtype, with distinctive features. OBJECTIVE: The objective of this study was to determine the prevalence of anxious depression and to define its clinical correlates and symptom patterns. METHOD: Baseline clinical and sociodemographic data were collected on 1450 subjects participating in the STAR*D study. A baseline Hamilton Rating Scale for Depression (HAM-D) Anxiety/ Somatization factor score of > or =7 was considered indicative of anxious depression. The types and degree of concurrent psychiatric symptoms were measured using the Psychiatric Diagnostic Screening Questionnaire (PDSQ), by recording the number of items endorsed by study participants for each diagnostic category. MDD symptoms were assessed by clinical telephone interview with the 30-item Inventory of Depressive Symptomatology (IDS-C30). RESULTS: The prevalence of anxious depression in this population was 46 %. Patients with anxious MDD were significantly more likely to be older, unemployed, less educated, more severely depressed, and to have suicidal ideation before and after adjustment for severity of depression. As far as concurrent psychiatric symptoms are concerned, patients with anxious depression were significantly more likely to endorse symptoms related to generalized anxiety, obsessive compulsive, panic, post-traumatic stress, agoraphobia, hypochondriasis, and somatoform disorders before and after adjustment for severity of depression. Anxious-depression individuals were also significantly less likely to endorse IDS-C30 items concerning atypical features, and were significantly more likely to endorse items concerning melancholic/endogenous depression features. CONCLUSION: This study supports specific clinical and sociodemographic correlates of MDD associated with high levels of anxiety (anxious depression).  相似文献   
65.

Background  

Improving health in our nation requires strengthening four major domains of the health care system: personal health management, health care delivery, public health, and health-related research. Many avoidable shortcomings in the health sector that result in poor quality are due to inaccessible data, information, and knowledge. A national health information infrastructure (NHII) offers the connectivity and knowledge management essential to correct these shortcomings. Better health and a better health system are within our reach.  相似文献   
66.
Electrolyte Medium Effects on Measurements of Palmar Skin Potential   总被引:1,自引:0,他引:1  
Two experiments with 12 subjects each compared skin potential recordings taken simultaneously with four different electrolytes. These were polyethylene glycol, hydrated agar (at a site presoaked with water), fresh agar (i.e., not presoaked), and Unibase. The glycol controlled epidermal hydration at a minimal level, while presoaking produced a high level of hydration at the hydrated agar site. Fresh agar and Unibase represented normal recording conditions for these two electrolytes which have been recommended as “standard” for electrodermal measurements. This design permitted a comparison of two standard electrolytes with each other and with recordings from hydrated and unhydrated sites. These comparisons were made for both monophasic negative SPRs and positive SPRs and the prestimulus levels associated with each. The results replicated previous studies in showing a large effect of epidermal hydration on skin potential measurements. Recordings with agar and Unibase did not differ significantly. The effects of hydration were interpreted in terms of a reduction in the resistance of the stratum corneum and of alterations in the functioning of the dermal and epidermal membranes as a result of blockage of the sweat gland pore. In the light of this interpretation, it was suggested that both agar and Unibase substantially alter the functioning of the sweat glands under some conditions, and neither may be entirely suitable for skin potential measurements.  相似文献   
67.
For some time, clinical reports have described impairment of affective and cognitive functions in iron deficient persons. Recent studies suggest that both brain biochemistry and cognitive performance capacity may be disrupted by inadequate intake of dietary iron, but the relationship of the possible neurophysiological effects to psychological ones is unclear. To examine the relationship of iron status to simultaneous measures of cortical activation and cognitive performance, 8 channels of electroencephalographic (EEG) data were recorded during a resting period and during the performance of several cognitive tasks in two groups of men. The EEG data were spectrally analyzed, and measures of total power and frequency of peak power in each of several bands of the power spectrum for each channel were used as predictors in multiple regression analyses with serum iron and serum ferritin as alternative criteria. Measures of power in the delta frequency in the resting period appeared relevant to iron status in both groups, perhaps indicating alertness or arousal level. Consistently in these regressions, the asymmetry of the EEG appeared relevant to iron and ferritin. These findings suggest that the combination of EEG and performance measures may help characterize the neuropsychological effects of trace element nutrition.  相似文献   
68.
Allelic exclusion of {alpha} chains in TCRs   总被引:2,自引:0,他引:2  
Although the ß chains of ß+ T cells exhibitallelic exclusion it has recently been shown that 20–30%of such cells express both chain alleles on their surface.Potentially these cells have dual specificity, and it has beensuggested that they may play a role in autoimmunity and alloreactlvtty.The analysis presented in this paper examines critically thepossibility that the observed violation of allelic exclusionof chain expression arises as a natural consequence of a chainrearrangement and intrathymlc positive selection. It is concludedthat, subject to certain identified conditions being satisfied,the observed frequency of T cells expressing two chains iscompatible with such a mechanism. However, It is an essentialassumption of the theory that, of the two ß chaincomplexes on these cells, only one mediates positive selection.It follows that to what extent both receptors are actually functionaldepends on whether an ß chain complex that has failedto satisfy the criterion of positive selection can mediate antigenrecognition in the periphery. In principle the answer to thisquestion may be different if one is considering autoreactlvltyor alloreactlvlty. Finally, attention is drawn to the apparentdiscrepancy between the frequency of peripheral T cells expressingtwo chains and the failure to find T cell clones of this phenotype.Possible explanations are discussed.  相似文献   
69.
Two adults with mild dementia and a history of memory loss and disequilibrium were seen in the eye clinic following complaints of acuity loss in the 20/30–20/70 (Snellen) range. Results from the fundus examination of one patient were entirely normal; the other showed minimal vascular attenuation and optic atrophy. Electrophysiology was remarkable: (1) Photopic ERG b-waves were reduced, delayed, and showed pronounced oscillations. (2) EOG light-rise potentials were absent or very small. (3) Binocular pattern-VER signals showed addition of the monocular signal. Scotopic ERG signals were normal. Brain biopsy and microscopy showed intercellular, autofluorescent ceroid deposits which provided a clear diagnosis of Kufs disease. Histology of model animal retinal cells show ceroid deposits in cell classes implicated by the human retinal signals. The cluster of electrophysiological results point toward early changes in the pigment epithelium and inner plexiform layer cells as a means of non-invasive diagnosis.  相似文献   
70.
The wave I-wave V delay in the auditory brain-stem response is commonly used as a diagnostic tool in otoneurology. Normative values have been established for different populations and different types of stimuli. This I-V delay has been known for some time as "central conduction time" or "central transmission time." This implies that the measure reflects in normal and in pathologic cases delays due to nerve conduction, synaptic transmission, and neural integration and is not caused by cochlear processes. By virtue of the traveling wave delay in the cochlea, amounting to some 4 ms from the base to the "500-Hz place," it is conceivable that this delay contributes to the I-V delay. From a series of 69 pontine angle tumors in which the auditory brain-stem response was recorded, we selected cases with an apparent peripheral origin of a prolonged I-V delay by comparing the whole-click response to responses derived from high-pass noise masking. It seems that cases with an increased I-V delay in the whole-click response but (almost) normal I-V delays in the narrow-band response are indicative of small intracanalicular acoustic neuroma.  相似文献   
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