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The identification of factors involved in herpes virus latency and reactivation is critical to a better understanding of the mechanisms essential to viral neuroinvasiveness and neurovirulence. Recurrent episodes of ocular herpes infections cause irreversible corneal scarring and are the primary cause of loss of vision due to an infectious agent in industrialized countries. In this study, we examined the ability of nicotine, a compound known to be involved in stress-associated immunomodulation and recognized as one of the most frequently used addictive agents, to induce ocular shedding in rabbits latently infected with herpes simplex virus type 1 (HSV-1) strain McKrae. New Zealand white rabbits latently infected with HSV-1 at 3-4 weeks post-inoculation were randomly divided into two groups. The corneas of all rabbits were free of lesions as verified by slit lamp biomicroscopy. One group received nicotine by transdermal patch (21 mg/day) for 20 days and the other group served as the control. Reactivation data were obtained by detection of virus in tear film collected by ocular swabbing performed concurrently with the administration of nicotine. Compilation of data from three separate experiments demonstrated that 16.5% (258/1560) of the swabs taken from rabbits treated with nicotine were positive for virus, compared with 8.3% (53/639) of swabs taken from controls. Rabbits receiving nicotine exhibited a significantly (P < 0.0001) higher rate of ocular shedding than controls. The concentration of nicotine in the serum was determined at various times (0-24 hrs) after new patch replacement. Peak (average) serum level of nicotine was obtained 8 hours after patch replacement and exhibited a broad range of values (0.233 microg/mL-6.21 microg/mL). These results suggest that an initial systemic exposure to nicotine significantly increases HSV-1 reactivation. Further studies are needed to reveal any effects of nicotine dependency and nicotine withdrawal on herpesvirus reactivation.  相似文献   
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Intravesical immunotherapy with bacillus Calmette-Guerin (BCG), Corynebacterium parvum (CP), keyhole limpet hemocyanin (KLH), and an extract of Allium sativum (AS) was studied in mice transplanted intravesically with mouse bladder tumor cells (MBT-2). Female C3H/He mice were anesthetized with sodium pentobarbital. Two X 10(5) MBT-2 cells were delivered into the bladder transurethrally using a small catheter, immediately after the posterior wall of the bladder had been electrocauterized. Bladder tumor became palpable or demonstrable microscopically in two weeks. Immunotherapy with BCG (2 X 10(6) CFU), CP (250 micrograms), KLH (50 micrograms), or AS (25 mg) was administered directly into the bladder via urethral catheter on day 1, day 6, or days 1 and 6. On day 21 the bladders and spleens were excised and weighed, and the bladders were examined macroscopically and microscopically for evidence of tumor. The results of the study showed that two treatments given one and six days after tumor transplant yielded the lowest tumor incidence and that CP and AS appeared equally effective or even slightly more effective than BCG in this model. These results suggest that clinical evaluation of CP or AS may be worthwhile.  相似文献   
35.
A 58-year-old postmenopausal woman with primary ovarian serous carcinoma presented with the syndrome of inappropriate antidiuresis (SIAD). Preoperative workup showed serum sodium level of 110 mEq/liter and antidiuretic hormone level of 3.3 pg/ml. The serum and urine osmolarity were 239 and 371, respectively. Antidiuretic hormone was demonstrated in tumor cells by immunohistochemistry. To the best of the authors’ knowledge, this represents the first case of SIAD due to primary ovarian tumor.  相似文献   
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Examined differences between compensation seeking (CS) veterans and noncompensation seeking (NCS) veterans on the Minnesota Multiphasic Personality Inventory-2 (MMPI-2) and other psychological measures in 142 combat veterans evaluated for posttraumatic stress disorder (PTSD) at an outpatient Veterans Affairs (VA) hospital PTSD clinic. Patients were grouped on the basis of their compensation seeking status, with 69% classified as CS for PTSD. The CS veterans achieved significantly more pathological scores across a wide range of psychological inventories and MMPI-2 validity indices, although they did not differ in frequency of PTSD diagnoses from NCS veterans. Implications of these findings are discussed, and clinicians are advised to be aware of the compensation seeking status of combat-veterans being evaluated for PTSD.  相似文献   
38.
Muscle tissue transplantation applied to regain or dynamically assist contractile functions is known as 'dynamic myoplasty'. Success rates of clinical applications are unpredictable, because of lack of endurance, ischemic lesions, abundant scar formation and inadequate performance of tasks due to lack of refined control. Electrical stimulation is used to control dynamic myoplasties and should be improved to reduce some of these drawbacks. Sequential segmental neuromuscular stimulation improves the endurance and closed-loop control offers refinement in rate of contraction of the muscle, while function-controlling stimulator algorithms present the possibility of performing more complex tasks. An acute feasibility study was performed in anaesthetised dogs combining these techniques. Electrically stimulated gracilis-based neo-sphincters were compared to native sphincters with regard to their ability to maintain continence. Measurements were made during fast bladder pressure changes, static high bladder pressure and slow filling of the bladder, mimicking among others posture changes, lifting heavy objects and diuresis. In general, neo-sphincter and native sphincter performance showed no significant difference during these measurements. However, during high bladder pressures reaching 40 cm H(2)O the neo-sphincters maintained positive pressure gradients, whereas most native sphincters relaxed. During slow filling of the bladder the neo-sphincters maintained a controlled positive pressure gradient for a prolonged time without any form of training. Furthermore, the accuracy of these maintained pressure gradients proved to be within the limits set up by the native sphincters. Refinements using more complicated self-learning function-controlling algorithms proved to be effective also and are briefly discussed. In conclusion, a combination of sequential stimulation, closed-loop control and function-controlling algorithms proved feasible in this dynamic graciloplasty-model. Neo-sphincters were created, which would probably provide an acceptable performance, when the stimulation system could be implanted and further tested. Sizing this technique down to implantable proportions seems to be justified and will enable exploration of the possible benefits.  相似文献   
39.
This study compared a traditional therapy for depression with Antidepressive therapy, a regime of meaningless, boring work designed to provoke the patient to an assertive expression of anger. The Ss were 32 neurotic and 24 psychotic patients at the Tuscaloosa, Alabama Veterans Administration Hospital. Improvement was measured by scores on the Purpose-In-Life Test (PIL) and the Self-Rating Depression Scale. All patient groups improved significantly within a 1-week period. Neurotics treated on the Antidepressive program improved significantly more than neurotics treated on the Traditional program. However, the data failed to indicate that either program was significantly more effective than the other in the treatment of psychotics.  相似文献   
40.
Previous studies have shown that recombinant interferon gamma (IFN-gamma), crude T cell supernatants, or appropriate T-cell lines can cause total inhibition of the growth of M. tuberculosis inside murine peritoneal macrophages. In similar experiments with human monocytes much smaller effects are seen. This could be due to the relative immaturity of these cells. Because dihydroxy vitamin D3 (1,25-(OH)2 D3) can cause phenotypic differentiation of immature leukemic lines into macrophage-like cells, we have explored the possibility that exposure to cholecalciferol metabolites in vitro might increase the ability of monocytes to control proliferation of M. tuberculosis, or cause monocytes to mature into cells able to respond appropriately to IFN-gamma. Incubation of monocytes with three cholecalciferol metabolites induced anti-tuberculosis activity to an extent that correlated with their binding affinities to the intracellular receptor protein for the derivatives. 1,25-(OH)2 D3 also primed monocytes for phorbol myristate acetate-triggered reduction of nitroblue tetrazolium. The effects were additive rather than synergistic with those of IFN-gamma. Monocytes incubated with IFN-gamma developed 25-OH D3 1-hydroxylase activity, detected by conversion of tritiated 25-(OH) D3 to a more polar metabolite which coeluted with 1,25-(OH)2 D3 on straight and reverse-phase HPLC. The latter is a more active form in vivo. These findings help to explain claims for the efficacy of vitamin D in the treatment of some forms of tuberculosis, and also the occasional finding of raised serum calcium, and disturbed vitamin D metabolism in these patients.  相似文献   
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