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21.

Background:

Meningitis remains a serious clinical problem in developing as well as developed countries. Delay in diagnosis and treatment results in significant morbidity and mortality. The role and levels of intrathecal endogenous cortisol is not known.

Objective:

To study the cerebrospinal fluid (CSF) cortisol levels and to evaluate its role as a diagnostic and therapeutic marker in acute bacterial meningitis.

Materials and Methods:

Thirty patients with acute bacterial meningitis with no prior treatment were evaluated. Cortisol levels were compared with 20 patients with aseptic (viral) meningitis and 25 control subjects.

Results:

Mean CSF cortisol level was 13.85, 3.47, and 1.05 in bacterial meningitis, aseptic meningitis, and controls, respectively. Mean CSF cortisol level in bacterial meningitis was significantly higher as compared to controls (P < 0.001). There was significant difference in CSFcortisol levels in bacterial and aseptic meningitis (P < 0.001).

Conclusions:

Cortisol levels in CSF are highly elevated in patients with acute bacterial meningitis. This suggests that intrathecalcortisol may serve as a valuable, rapid, relatively inexpensive diagnostic marker in discriminatingbetween bacterial and aseptic meningitis. This helps in earlier institution of appropriate treatment and thereby decreasing morbidity and mortality.  相似文献   
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OBJECTIVE: We investigated whether exercise pre-conditioning ameliorates stroke-induced blood-brain barrier (BBB) dysfunction by strengthening basal lamina. METHODS: Adult male Sprague-Dawley rats were subjected to a 30 minute exercise program on a treadmill each day for 3 weeks. Stroke was induced by a 2 hour middle cerebral artery (MCA) occlusion using an intraluminal filament in the exercised and non-exercised groups. BBB dysfunction was then determined by brain edema. Expression of collagen IV, the major component of basal lamina essential for maintenance of the endothelial permeability barrier, was quantitatively detected by Western blot and immunocytochemistry. Ex vivo techniques were used to compare collagen IV-labeled vessels in response to ischemic insult. RESULTS: Brain edema was significantly (p<0.05) reduced after stroke in the exercised group. Western blot analysis indicated that exercise pre-conditioning enhanced collagen IV expression and reduced the loss after stroke. Immunocytochemistry demonstrated that collagen IV-positive vessels were significantly (p<0.01) increased in exercised rats. In ex vivo study, after exercised brain was incubated with ischemic brain tissue, a significantly (p<0.01) higher expression of collagen IV in cortex and striatum was observed compared to non-exercised brain following the same treatment. The ex vivo study also revealed that matrix metalloproteinase (MMP)-9 plays a key role in exercise-strengthened collagen IV expression against ischemia/reperfusion injury. DISCUSSION: Our results indicate that exercise pre-conditioning improved BBB function and enhanced basal lamina, which involved MMP-9.  相似文献   
23.
An increased HLA DR2 frequency is seen in aplastic anemia patients   总被引:4,自引:3,他引:4  
Nimer  SD; Ireland  P; Meshkinpour  A; Frane  M 《Blood》1994,84(3):923-927
The underlying etiology of aplastic anemia is unknown in the majority of patients, although medications, chemical exposure, or viral infections can be implicated in some. Genetic susceptibility to a variety of diseases has been shown and it has recently been suggested that aplastic anemia is more common in individuals who are HLA DR2+ than in the general population. To examine this question, we retrospectively analyzed the results of HLA-DR typing in 75 aplastic anemia patients who received antithymocyte globulin (ATG) therapy or an HLA-matched sibling bone marrow transplant at UCLA between 1978 and 1989. Thirty-one patients were DR2+, a 1.9-fold higher incidence than the expected number of 16.6 patients (P < .0005). Of the 37 patients who received ATG, 33 were evaluable for a response; 14 patients had either a complete (4 patients) or partial (10 patients) response, for an overall response rate of 42.4%. Of the 14 DR2+ patients who received ATG, 7 responded, for a 50% response rate, which is not significantly higher than the response rate for the DR2- patients (7 of 19 [36.8%]; P = .50). The median survival of patients who are DR2+ was slightly, but not significantly, longer than that of the DR2- patients in the ATG group (P = .19). Although the incidence of HLA DR2 was clearly increased in these patients with aplastic anemia, response rates to ATG were not significantly different in the DR2+ and DR2- patients.  相似文献   
24.
Transgenic mice with both alleles of the p53 tumor suppressor gene product 'knocked out' by gene targeting are susceptible to early development of tumors, chiefly lymphomas and sarcomas. Compared with the control group, administration of dehydroepiandrosterone (DHEA) at 0.3% of the diet to male p53-deficient mice extended their lifespan by delaying death due to neoplasms (from 105 to 166 days on study, P = 0.002), primarily by suppressing lymphoblastic lymphoma (from 45 to 6% of neoplastic deaths, P = 0.010). Treatment with a synthetic DHEA analog, 16alpha-fluoro-5-androsten-17-one (compound 8354), at 0.15% of the diet also increased lifespan, to 140 days for mice that developed tumors (P = 0.037). The effects of these steroids on lifespan and tumor development did not appear to be strongly related to inhibition of food consumption and weight gain, in that a group pair-fed with control diet to the reduced food consumption of the DHEA-treated group developed and died of the same types of neoplasms at the same rate as the controls fed ad libitum. The chemopreventive effect of these steroids has been proposed to be due to suppression of DNA synthesis by inhibition of glucose 6-phosphate dehydrogenase, the rate-limiting enzyme of the pentose phosphate pathway. Although DHEA and its analog are strong non- competitive inhibitors of this enzyme in vitro, treatment with DHEA did not deplete cellular nucleotide pools in the liver, as would have been predicted. The chemopreventive effect of DHEA in this model may be due to steroid-induced thymic atrophy and suppression of T cell lymphoma, permitting these mice to survive long enough to develop tumors with longer latency.   相似文献   
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PURPOSE: This study evaluates the benefits of targeted early rehabilitation at home after total hip or knee replacement surgery and analyses the cost effectiveness of such a scheme. METHOD: Patients recovering from Total hip replacement (THR, n = 220) and Total knee replacement (TKR, n = 174) were assessed in a NHS District General Hospital setting. Suitability of patients for early rehabilitation at home scheme (RAHS) was assessed at the pre-operative clinic by rehabilitation team. Length of in-patient stay (LOSH), duration on the scheme, number of bed days saved, cost appraisal, readmission rates and complications were recorded. RESULTS: Targeted early rehabilitation resulted in reduced hospital stay (from 14-8.17 days for THR and from 12-8.21 days for TKR), without any increase in complication rates. Significance testing revealed no statistical difference between the patient groups with regards to age, residence status, mobility and transfer ability on their length of stay in hospital or on the rehabilitation scheme. The patients who underwent total knee replacement required significantly more number of visits by the rehabilitation team than those who underwent total hip replacement (p value < 0.05). This resulted in an overall saving of pound 301,124 for the trust over the study period. CONCLUSIONS: Targeted early rehabilitation resulted in reducing the length of hospital stay without an increase in complication rates. The use of such a scheme brought significant savings to the trust without an increase in readmission rates.  相似文献   
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Smoking is a high-risk behavior that affects the health and economic welfare of society. Thus, it is important to quantify the economic burden smoking places on social institutions in the United States.
OBJECTIVE: The purpose of this review paper is to analyze smoking cost studies and to provide estimates that represent the economic costs of smoking from different perspectives of society, and as a whole.
METHODS: Current Contents (1996–), Health Star (1970–), and Medline (1966–) databases were searched through the use of pertinent subject headings and key words: tobacco use, smoking, cost, and economics. The internet was utilized to identify potential sources of epidemiological and cost information on smoking. Recent cost-of-illness studies using different methodologies: human capital, incidence, and prevalence were chosen for review based on their relevance.
RESULTS: Preliminary results indicate that the published cost studies available underestimate the "true" costs of smoking. The most current articles approximate annual direct medical costs to health care payers of $50 billion (1993); inflating to 1997 equals $59 billion or $1,200 per smoker. Although the latest cost studies do not attempt to estimate indirect costs, past studies have found indirect costs to be 1.5–2 times the direct costs. Therefore, using direct and indirect costs we estimate total smoking costs to be $150 billion (1993); inflating to 1997 equals $176 billion or $3,500 per smoker.
CONCLUSION: Quantifying the cost of smoking is a difficult task due to tobacco use infiltrating many aspects of life and the dependency of cost on perspective. Cost-of-illness studies provide cost estimation data which can be useful in aiding decision-makers who are allocating health care resources.  相似文献   
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