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991.
STUDY DESIGN: Report of a patient with paraplegia caused by vertebral sarcoidosis. OBJECTIVES: To report a rare case of vertebral sarcoidosis accompanied by progressive neurologic symptoms from the lower extremities, and to discuss the diagnostic and therapeutic approach to its management. SUMMARY OF BACKGROUND DATA: Vertebral sarcoidosis is a rare condition, and only a few case reports exist in the literature. A needle or open biopsy is required to establish the diagnosis. In most cases, treatment with steroids improves associated neurologic symptoms. Operative intervention is necessary in cases with progressive vertebral destruction, spinal instability, and impending or progressive neurologic deterioration. METHODS: Operative treatment by a two-stage anterior vertebrectomy and fusion followed by posterior stabilization was given to a patient with vertebral sarcoidosis and progressive neurologic deterioration of the lower extremities. RESULTS: After surgery, the patient had a complete neurologic recovery and satisfactory spinal fusion. CONCLUSIONS: In the absence of any spinal instability, neurologic symptoms associated with vertebral sarcoidosis respond satisfactorily to nonoperative treatment with steroids. Progressive neurologic deterioration or spinal instability caused by bone destruction requires operative intervention. Anterior vertebrectomy and fusion combined with posterior stabilization provided a satisfactory result for the patient in this report.  相似文献   
992.
OBJECTIVES: To investigate the relationship of intestinal permeability in children and adolescents with inflammatory bowel disease (IBD) to disease activity, disease extent, and response to therapy. Study design: Patients with new and established diagnoses of IBD (12 Crohn's disease [CD] and 18 ulcerative colitis [UC]) were studied. Intestinal permeability was evaluated by measuring with high-performance liquid chromatography 5-hour urinary excretion ratio of lactulose/L-rhamnose (L/Rh). RESULTS: In 8 of 9 patients with active CD, the L/Rh ratio was higher than the reference range (0.006 to 0.074, n = 36). In inactive CD (n = 3) the L/Rh ratio was within the reference range. In 6 of 7 patients with active extensive UC, the L/Rh ratio was elevated. In inactive extensive UC (n = 6) the normal permeability ratio was shown. In both active CD and active extensive UC, the frequency of elevated intestinal permeability was significantly greater than values in both inactive forms. The permeability ratio was normal in 4 of 5 patients with active left-sided colitis. In 5 of 7 patients (3 CD, 4 UC), repeat permeability values entered the reference range after acute phase therapy. Two patients with persistently elevated intestinal permeability (1 CD, 1 UC) had a disease flare-up within 6 months. CONCLUSIONS: Intestinal permeability is a marker of disease activity in CD and extensive UC. Serial permeability test may be useful in monitoring disease activity.  相似文献   
993.
Human and murine osteocalcin genes demonstrate similar cell-specific expression patterns despite significant differences in gene locus organization and sequence variations in cis-acting regulatory elements. To investigate whether differences in these regulatory regions result in an altered response to 1,25-dihydroxyvitamin D3 [1,25-(OH)2D3] in vivo, we compared the response of the endogenous mouse osteocalcin gene to a bacterial reporter gene directed by flanking regions of the human osteocalcin gene in transgenic mice. Transgene expression colocalized with endogenous osteocalcin expression in serial sections, being detected in osteoblasts, osteocytes and hypertrophic chondrocytes. In calvarial cell culture lysates from transgenic and nontransgenic mice, the endogenous mouse osteocalcin gene did not respond to 1,25-(OH)2D3 treatment. Despite this, transgene activity was significantly increased in the same cells. Similarly, Northern blots of total cellular RNA and in situ hybridization studies of transgenic animals demonstrated a maximal increase in transgene expression at 6 h after 1,25-(OH)2D3 injection (23.6+/-3.6-fold) with a return to levels equivalent to uninjected animals by 24 h (1.2+/-0.1-fold). This increase in transgene expression was also observed at 6 h after 1,25-(OH)2D3 treatment in animals on a low calcium diet (25.2+/-7.7-fold) as well as in transgenic mice fed a vitamin D-deficient diet containing strontium chloride to block endogenous 1,25-(OH)2D3 production (7.5+/-0.9-fold). In contrast to the increased transgene expression levels, neither endogenous mouse osteocalcin mRNA levels nor serum osteocalcin levels were significantly altered after 1,25-(OH)2D3 injection in transgenic or nontransgenic mice, regardless of dietary manipulations, supporting evidence for different mechanisms regulating the response of human and mouse osteocalcin genes to 1,25-(OH)2D3. Although the cis- and trans-acting mechanisms directing cell-specific gene expression appear to be conserved in the mouse and human osteocalcin genes, responsiveness to 1,25-(OH)2D3 is not. The mouse osteocalcin genes do not respond to 1,25-(OH)2D3 treatment, but the human osteocalcin-directed transgene is markedly upregulated under the same conditions and in the same cells. The divergent responses of these homologous genes to 1,25-(OH)2D3 are therefore likely to be due to differences in mouse and human osteocalcin-regulatory sequences rather than to variation in the complement of trans-acting factors present in mouse osteoblastic cells. Increased understanding of these murine-human differences in osteocalcin regulation may shed light on the function of osteocalcin and its regulation by vitamin D in bone physiology.  相似文献   
994.
995.
OBJECTIVES: To characterize the reasons ambulatory patients use hospital emergency departments (EDs) for outpatient care and to determine the proportion of ED patients who initially are assessed as having nonurgent conditions, but subsequently are hospitalized. DESIGN: Cross-sectional survey during a single 24-hour period of time. SETTING: Fifty-six hospital EDs nationwide. PATIENTS OR OTHER PARTICIPANTS: Consecutive ambulatory patients presenting for care. Patents who arrived by ambulance were excluded. RESULTS: Of 6441 ambulatory patients (79 percent of all ED visits) who were eligible for study, interviews were obtained from 6187 (96 percent). A total of 5323 patients (86 percent) had clinical reasons or preferences for seeking care at an ED, including 2799 (45 percent) who thought they had an emergency or an urgent condition or were too sick to go elsewhere. Nineteen percent (n=1199) reported that they were sent to the ED by a health care professional. Patients with a regular clinician or with insurance cited similar reasons for seeking care at an ED. A total of 3062 patients (50 percent) cited 1 or more nonfinancial barriers to care as an important reason for coming to the ED, and 949 (15 percent) cited financial considerations. A total of 3045 patents (49 percent of ambulatory patients and 37 percent of total ED visits) were assessed at triage as having a nonurgent condition; 166 of them (5.5 percent; 95 percent confidence interval, 4.7 percent-6.3 percent) were admitted to the hospital. CONCLUSIONS: Most ambulatory patients seek care in an ED because of worrisome symptoms or nonfinancial barriers to care. Although many ambulatory patients appear to have nonurgent conditions based on triage classification, a small but disturbing percentage of nonurgent patients are hospitalized.  相似文献   
996.
Preclinical studies were designed to investigate the feasibility and safety of recombinant adenoviruses transduced into the hepatic artery of nonhuman primates. The vectors used are recombinant adenoviruses deleted in E1 and contain either a temperature-sensitive mutation in the E2a gene, which encodes a defective DNA-binding protein at nonpermissive temperatures, or a deletion of the E4 region, including open reading frame (ORF) 6. Six 8- to 10-kg baboons underwent femoral artery cannulation, and angiographic techniques were used to introduce vector selectively into either a portion of the right lobe of the liver via a branch of the right hepatic artery or the common hepatic artery. Necropsies were performed at 4, 29, or 61 days. Serial sequential liver biopsies were performed in the baboons that survived 29 or 61 days. In the 2 baboons with vector transduction into the right hepatic artery, X-Gal histochemical analysis of the liver showed evidence of quantitatively increased gene transfer in the targeted lobe; however, gene transfer was present throughout the liver. Quantitative analysis of histopathology showed that portal inflammation was present throughout both livers transduced with the highest dose of vector. No differences were seen in the level of portal inflammation in targeted and untargeted lobes despite the observed qualitative and quantitative differences in gene expression. Southern blot analysis of total cellular DNA isolated from targeted and nontargeted lobes showed similar levels of viral DNA throughout the liver. Polymerase chain reaction (PCR) analysis was able to detect viral DNA sequence in gonads and brain as well as many other tissues in baboons treated with high-dose vector. In baboons treated with lower doses of an E1-E4 deleted vector expressing the human ornithine transcarbamylase (OTC) gene, DNA was detectable by nested PCR in liver but not gonads at days 29 and 61. The data suggest that intraarterial administration of recombinant adenoviral E1-E4 deleted vector is feasible and safe. At high doses of vector, widespread dissemination of vector DNA is seen. At low doses, hepatic gene transfer is not associated with vector DNA dissemination to gonads.  相似文献   
997.
This study concerns whether the pancreatic beta cell expresses cell-surface ectopeptidases that are capable of proteolysis of peptide hormones and neuropeptides that modify glucose-dependent insulin release. These biochemical investigations of the RINm5F cell line found that these cells express ectopeptidases. We have characterized the limited endoproteolysis of GLP-1 (7-36) amide that occurs in the presence of RINm5F plasma membranes. The products and the sensitivity to specific peptidase inhibitors of the proteolysis is characteristic of neutral endopeptidase (NEP) 24.11. Vasoactive intestinal polypeptide (VIP), pituitary adenylate cyclase-activating peptide (PACAP), amylin, glucagon, glucose-dependent insulinotropic polypeptide (GIP), and exendin-4 also undergo proteolysis in the presence of RIN cell membranes. NEP 24.11-activity in RIN cell membranes was confirmed using a specific fluorogenic assay, by histochemistry, and by comparison with the recombinant enzyme with respect to the kinetics of proteolysis of GLP-1 (7-36) amide and of a fluorogenic substrate. Specific fluorogenic assays revealed the presence of aminopeptidase N and the absence of aminopeptidase A and of dipeptidylpeptidase IV.  相似文献   
998.
Effects of antihypertensive therapy on left atrial function   总被引:1,自引:0,他引:1  
OBJECTIVES: To investigate left atrial (LA) function as a reservoir, as a conduit and as a booster pump in essential hypertension (EH). LA volumes were echocardiographically measured in 28 untreated hypertensive patients and in 20 control subjects. BACKGROUND: LA makes a large contribution in left ventricular filling, especially in patients with impaired diastolic function. LA function is fundamental in left ventricular filling in hypertensive patients as hypertension results in left ventricular diastolic dysfunction. METHODS: Diagnosis of EH (blood pressure > 140/90 mm Hg) was based on three repeated readings of blood pressure (BP). Patients with myocardial infarction, cardiomyopathy, valvular or congenital heart disease were excluded. Doppler diastolic early (E) and late (A) velocity of mitral inflow were measured. The following indexes were calculated: left ventricular mass index (LVMI) using the Penn convention; left ventricular stroke volume (LVSV); LA reservoir volume (LARV = LA maximal volume at mitral valve opening minus minimal volume); LA conduit volume (LACV = LVSV-LARV). Atrial systolic function was assessed by calculating the active emptying fraction (volume at onset of atrial systole minus minimal volume/volume at onset of atrial systole, the E/A ratio and the LA ejection force (0.5 rho A2 MOA, where rho = the density of blood, MOA = mitral orifice area from the parasternal short axis view). Measurements were obtained in all hypertensive patients before and after 16 weeks administration of either enalapril (10 or 20 mg) or enalapril +/- chlorthalidone (20/25 mg) once a day. RESULTS: After 16 weeks of treatment, BP was reduced significantly (from 172/110 to 137/86 mm Hg, P < 0.001). LVMI decreased significantly as well (from 141 to 123 g/m2) although it was higher compared to controls (94 g/m2, P < 0.001). LARV decreased significantly (from 35.4 to 29.3 cm3, P < 0.05) while LACV increased significantly (from 43.8 to 51.3 cm3, P < 0.05), LA active emptying fraction and E/A ratio did not change. LA ejection force decreased significantly (from 20.9 to 18.1 kdynes, P < 0.05) but it was greater than controls (16.7 kdynes, P < 0.01). There was a positive relationship of LVMI to LARV (P < 0.01) in controls (r = 0.77) which held true in hypertensive patients, before (r = 0.72) and after treatment (r = 0.69). There was a negative relationship of LVMI to LACV (P < 0.01) in controls (r = -0.65), and in hypertensive patients untreated (r = -0.74) and after treatment (r = -0.72). CONCLUSIONS: Our results showed that in hypertensive patients, LA reservoir function increases and LA conduit function decreases, while LA ejection force increases. Antihypertensive treatment with enalapril and/or thiazide, induces normalisation of the LA function in parallel to left ventricular hypertrophy regression.  相似文献   
999.
1000.
The quantification of biochemical markers of bone formation and resorption with kinetic measures of bone turnover is an essential step in their validation. Some biochemical markers have been validated by quantification against formation and resorption rates measured by calcium kinetics in adults with bone disease. However, none has been validated in healthy individuals who are undergoing skeletal growth and bone consolidation. Therefore, we have measured biochemical markers of bone formation (serum osteocalcin [OC], bone-specific alkaline phosphatase [BAP], and total alkaline phosphatase [ALP]) and resorption (serum tartrate resistant acid phosphatase [TRAP], urinary cross-linked N teleopeptides of type I collagen/creatinine [NTx/Cr], and hydroxyproline/creatinine [OHP/Cr]) in healthy females aged 11-32 years (n = 31) after an overnight fast to determine their relationship with bone formation (Vo+) and bone resorption (Vo-) as measured by calcium kinetics and balance. All biochemical markers were highly intercorrelated (r > 0.6, p < 0.001) as were Vo+ and Vo- (r = 0.91, p < 0.001). Highly significant correlations were present between bone formation measured by calcium kinetics (Vo+) and serum levels of bone biochemical markers (OC, r = 0.82, p = 0.001; ALP, r = 0.92, p = 0.001; and BAP, r = 0.90, p = 0.001) and between bone resorption measured by calcium kinetics (Vo-) and fasting serum levels and urine creatinine ratios of biochemical markers (TRAP, r = 0.77, p < 0.001; OHP/Cr, r = 0.79, p < 0.001; and NTx/Cr, r = 0.70, p < 0.001). Thus, biochemical markers of bone formation and resorption can be used to predict calcium kinetic rates during skeletal growth and the early years of formation of peak bone mass, ages at which strategies to build peak bone mass are important. Biochemical markers of formation and resorption are equally useful in predicting either the bone formation rate or the resorption rate.  相似文献   
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