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21.
Demonstration of a B-lymphocyte mitogen produced by the Lyme disease pathogen, Borrelia burgdorferi. 下载免费PDF全文
Lyme disease refers to the multisymptomatic illness in humans which results from infection with the tick-borne spirochete Borrelia burgdorferi. The white-footed mouse is the major reservoir for B. burgdorferi and, upon infection, certain inbred mice develop symptoms similar to those reported in human disease. Sonicated preparations of washed spirochetes were found to have potent mitogenic activity when cultured with lymphocytes from naive C57BL/6, C3H/HeJ, or BALB/c mice. The activity of the B. burgdorferi sonicate was approximately fourfold greater than that of a similarly prepared Escherichia coli sonicate. Polymyxin B efficiently inhibited the mitogenic activity of the E. coli sonicate but only slightly inhibited that of the B. burgdorferi sonicate, suggesting that a lipid A-containing lipopolysaccharide was not responsible for the B. burgdorferi activity. Kinetic analysis indicated peak proliferation at 2 to 3 days of culturing, suggesting polyclonal activation. B- and T-lymphocyte depletion experiments indicated that the major cell type responding to the B. burgdorferi mitogen was the B lymphocyte. This mitogen stimulated murine B cells not only to proliferate but also to differentiate into antibody-secreting cells, as demonstrated by the production of immunoglobulin by stimulated splenocytes. Furthermore, the sonicated preparation stimulated the B-cell tumor line CH12.LX to secrete immunoglobulin in the absence of accessory cells. B. burgdorferi also stimulated interleukin-6 production in splenocyte cultures. The observation that B. burgdorferi can stimulate activation of and immunoglobulin production by normal B lymphocytes may directly reflect on the development of arthritis associated with persistent infection by this organism. 相似文献
22.
S. Shousha A. Schoenfeld Jill Moss I. Shore H. D. Sinnett 《Ultrastructural pathology》1994,18(5):519-523
Although recent epidemiologic studies suggest that silicone augmentation of the breast is not associated with an increased risk of mammary carcinoma, cases of breast carcinoma arising in augmented breasts are being increasingly encountered as a large number of patients who had augmentation are getting older. A case of a 51-year-old woman with a 20-year history of breast augmentation who developed an invasive cribriform carcinoma associated with extensive microcalcification is presented. The patient had submammary silicone implants 20 years ago that were replaced, because of local complications, in subpectoral positions 10 years later. Dispersive X-ray microanalysis failed to demonstrate silicone in sections of the tumor and adjacent breast tissue. Appropriately fixed tumor tissue was available for electron microscopic examination. The tumor cells were rich in mitochondria, and their luminal surfaces were endowed with abundant microvilli, but the cell surfaces that came closest to the calcified microspheriols were devoid of microvilli and had cellular buddings between the microspheriols. It is suggested that the tumor cells might have been actively involved in the process of microcalcification. 相似文献
23.
A controlled trial of transcutaneous electrical nerve stimulation (TENS) and exercise for chronic low back pain 总被引:11,自引:0,他引:11
R A Deyo N E Walsh D C Martin L S Schoenfeld S Ramamurthy 《The New England journal of medicine》1990,322(23):1627-1634
A number of treatments are widely prescribed for chronic back pain, but few have been rigorously evaluated. We examined the effectiveness of transcutaneous electrical nerve stimulation (TENS), a program of stretching exercises, or a combination of both for low back pain. Patients with chronic low back pain (median duration, 4.1 years) were randomly assigned to receive daily treatment with TENS (n = 36), sham TENS (n = 36), TENS plus a program of exercises (n = 37), or sham TENS plus exercises (n = 36). After one month no clinically or statistically significant treatment effect of TENS was found on any of 11 indicators of outcome measuring pain, function, and back flexion; there was no interactive effect of TENS with exercise. Overall improvement in pain indicators was 47 percent with TENS and 42 percent with sham TENS (P not significant). The 95 percent confidence intervals for group differences excluded a major clinical benefit of TENS for most outcomes. By contrast, after one month patients in the exercise groups had significant improvement in self-rated pain scores, reduction in the frequency of pain, and greater levels of activity as compared with patients in the groups that did not exercise. The mean reported improvement in pain scores was 52 percent in the exercise groups and 37 percent in the nonexercise groups (P = 0.02). Two months after the active intervention, however, most patients had discontinued the exercises, and the initial improvements were gone. We conclude that for patients with chronic low back pain, treatment with TENS is no more effective than treatment with a placebo, and TENS adds no apparent benefit to that of exercise alone. 相似文献
24.
C. Devos P. Robberecht P. Nokin M. Waelbroeck M. Clinet J. C. Camus P. Beaufort P. Schoenfeld J. Christophe 《Naunyn-Schmiedeberg's archives of pharmacology》1985,331(1):71-75
Summary We evaluated the effects of ischemic injury on the myocardial adenylate cyclase system, 5 h after ligation of the left anterior descending coronary in 5 anesthetized dogs. Crude cardiac membrane preparations were isolated from control and ischemic areas of ventricular myocardium and tested for: 1. L-(125I)iodocyanopindolol binding, in the absence and presence of ±-isoprenaline and GTP, and 2. adenylate cyclase activity. The density of beta-adrenoceptors increased by 35% in membranes from ischemic areas while the proportion of receptors in a high affinity state for ±-isoprenaline decreased from 43% to 20%. Adenylate cyclase activities in the basal state and under stimulation with NaF, forskolin, Gpp(NH)p, ±-isoprenaline and VIP were all markedly and similarly reduced, being only about 30% of comparable activities in membranes from control areas. The ±-isoprenaline subsensitivity of cardiac adenylate cyclase can, thus, be attributed to a defective enzymatic system and not to a reduction in the number of beta-adrenoceptors implying that the internal components of the system were more sensitive to acute ischemia than the outward oriented hormone receptors. It is tempting to ascribe this uncoupling to a functional depletion in the guanine nucleotide-binding regulatory protein Ns that might reflect a loss of high energy phosphate stores including GTP.Abbreviations CYP
cyanopindolol
- Gpp(NH)p
5-guanyl imidodiphosphate
- VIP
vasoactive intestinal peptide
- Ns
guanine nucleotide-binding regulatory protein 相似文献
25.
The clinical usefulness of the renal allograft biopsy in the cyclosporine era: a prospective study 总被引:9,自引:0,他引:9
Pascual M Vallhonrat H Cosimi AB Tolkoff-Rubin N Colvin RB Delmonico FL Ko DS Schoenfeld DA Williams WW 《Transplantation》1999,67(5):737-741
BACKGROUND: The renal allograft biopsy is generally accepted as the gold standard for clarifying the cause of renal dysfunction. However, the clinical usefulness of this procedure has rarely been studied prospectively, nor have most studies included follow-up of patients to delineate the influence of the biopsy on clinical outcome. In this study, we evaluated prospectively the clinical usefulness of the allograft biopsy in renal transplant recipients receiving cyclosporine (CyA). METHODS: During a 21-month period, 82 biopsies were performed. In 54 instances (47 patients), we outlined a presumed diagnosis and tentative treatment plan before the procedure. After the biopsy, a definitive diagnosis was made and an appropriate patient management approach was instituted. We analyzed the incidence of change in patient management that resulted from histological findings. All patients were followed to monitor their response to treatment and allograft survival. In cases of biopsy-proven acute cellular rejection (ACR) or cyclosporine (CyA) toxicity, clinical and laboratory data from the day of the biopsy were reviewed to determine their diagnostic value. RESULTS: One biopsy specimen was inadequate for definitive interpretation. The biopsy findings resulted in a change in patient management in 22 (41.5%) of the remaining 53 cases (change group). The incidence of altered patient management was 38.7% in biopsy specimens taken in the first month, 55.6% between 1 and 12 months, and 38.5% after 1 year posttransplantation. A change in management was required in 2 of 2 patients with chronic allograft dysfunction, in 44.4% of the 45 patients with acute allograft dysfunction, and in none of the patients with delayed graft function (n=6). Within the first week of treatment 19 of 22 (86.4%) in the change group and 25 of 31 (80.6%) in the no change group had a positive response to therapy. The 1-year allograft survival rate was also similar between the two groups. None of the clinical and laboratory data was useful in distinguishing ACR from CyA toxicity. CONCLUSIONS: Renal allograft biopsy findings alter patient management recommendations in approximately 40% of patients in whom a presumptive diagnosis had been made on the basis of clinical and laboratory findings. Patients who had a change in patient management because of biopsy findings demonstrated a response to therapy and allograft survival similar to those of patients who had no alteration in management plan after the biopsy. 相似文献
26.
Gilbert JR Pascual M Schoenfeld DA Rubin RH Delmonico FL Cosimi AB 《Transplantation》1999,67(2):246-253
BACKGROUND: Due to the limited supply and increased demand for donor livers, waiting times are progressively lengthening, which may lead to transplantation at more advanced and less cost-effective stages of disease. The purpose of this study was to evaluate the outcomes and hospital charges of liver transplantation during two recent eras to identify areas for providing more cost-effective care. METHODS: A total of 144 primary liver allografts were performed from 1991 to 1996. Patient characteristics, outcome measures, and hospital charges were compared for patients receiving allografts between 1991 and 1993 (group A) versus those receiving grafts between 1994 and 1996 (group B) using unpaired Student t tests for continuous data and chi-squared tests for categorical data. RESULTS: In comparing groups A and B, no significant differences in patient demographics, relative contraindications, or indication for transplantation existed; median waiting time from date of listing until transplant increased from 88 days to 159 days; and a shift in UNOS priority status at time of transplantation occurred, as the percentage of patients requiring inpatient care increased from 58% to 75% (P=0.034). Despite this, patient hospital and 1-year survival significantly improved from 75.0% to 90.3% (P=0.016), and from 68.1% to 88.9% (P=0.002), respectively. Total hospital charges, without correction for inflation, were $174,908+/-16,388 in A and $193,525+/-14,444 in B (P=0.288). The increased charges were associated with longer inpatient length of stay (LOS) before transplant, resulting in increased pretransplant charges from $24,088+/-4134 (A) to $39,490+/-6,196 (B) (P=0.011). Room and service (54%) was the largest pretransplant contributor to charges, while blood products (23%), room and service (21%), organ acquisition (13%), and operating room charges (11%) contributed the most after transplant. CONCLUSIONS: Longer waiting times resulting in transplantation at later stages of disease have occurred, leading to longer pretransplant LOS and its associated charges. Despite more advanced disease, patient survival rates have significantly improved with fewer infection-related deaths. LOS pretransplant, blood products, and operating room services represent potential areas for providing more cost-effective care. 相似文献
27.
Review article: nonsteroidal anti-inflammatory drug-associated gastrointestinal complications—guidelines for prevention and treatment 总被引:3,自引:0,他引:3
Schoenfeld Kimmey Scheiman Bjorkman & Laine 《Alimentary pharmacology & therapeutics》1999,13(10):1273-1285
Chronic ingestion of NSAIDs increases the risk for gastrointestinal complications, which range from dyspepsia to gastrointestinal bleeding, obstruction, and perforation. Among patients using NSAIDs, 0.1 to 2.0% per year suffer serious gastrointestinal complications. Patients who require analgesic therapy should be carefully assessed for the lowest possible dosage and shortest duration of NSAID use and for the potential of treatment with a non-NSAID pain reliever. These patients should also be assessed for factors that increase their risk of gastrointestinal complications, including increased age, concomitant anticoagulant or corticosteroid use, and past history of NSAID-associated gastrointestinal complications. The exact association between Helicobacter pylori infection and NSAID-related ulcer disease is unclear, and the routine testing and treatment of all NSAID using patients for H. pylori infection is not recommended at this time. NSAID-using patients who suffer from dyspepsia should have NSAIDs discontinued, the dosage changed, or be changed to a different class of NSAID. If NSAIDs cannot be discontinued, then an antisecretory agent should be initiated. Misoprostol prevents NSAID-associated gastrointestinal complications. Proton pump inhibitors are the most effective at healing NSAID-associated ulcers among patients who cannot discontinue NSAID therapy. 相似文献
28.
Thomas C Neylan Maryanne Lenoci Melissa L Maglione Nicholas Z Rosenlicht Thomas J Metzler Christian Otte Frank B Schoenfeld Rachel Yehuda Charles R Marmar 《Neuropsychopharmacology》2003,28(9):1666-1676
Metyrapone blocks cortisol synthesis, which results in the stimulation of hypothalamic cortiocotropin-releasing factor (CRF) and a reduction in delta sleep. We examined the effect of metyrapone administration on endocrine and sleep measures in male subjects with and without chronic PTSD. We hypothesized that metyrapone would result in a decrease in delta sleep and that the magnitude of this decrease would be correlated with the endocrine response. Finally, we utilized the delta sleep response to metyrapone as an indirect measure of hypothalamic CRF activity and hypothesized that PTSD subjects would have decreased delta sleep at baseline and a greater decrease in delta sleep induced by metyrapone. Three nights of polysomnography were obtained in 24 male subjects with combat-related PTSD and 18 male combat-exposed normal controls. On day 3, metyrapone was administered during normal waking hours until habitual sleep onset preceding night 3. Endocrine responses to metyrapone were measured in plasma obtained the morning following sleep recordings, the day before and after administration. Repeated measures ANOVAs were conducted to compare the endocrine and sleep response to metyrapone in PTSD and controls. PTSD subjects had significantly less delta sleep as indexed by stages 3 and 4, and total delta integrated amplitude prior to metyrapone administration. There were no differences in premetyrapone cortisol or ACTH levels in PTSD vs controls. PTSD subjects had a significantly decreased ACTH response to metyrapone compared to controls. Metyrapone caused an increase in awakenings and a marked decrease in quantitative measures of delta sleep that was significantly greater in controls compared to PTSD. The decline in delta sleep was significantly associated with the magnitude of increase in both 11-deoxycortisol and ACTH. The results suggest that the delta sleep response to metyrapone is a measure of the brain response to increases in hypothalamic CRF. These data also suggest that the ACTH and sleep EEG response to hypothalamic CRF is decreased in PTSD. 相似文献
29.
30.
JC VANCE DC CHANT DI TUDEHOPE PH GRAY AJ HAYES 《Journal of paediatrics and child health》1997,33(6):504-508
Objectives: To describe the physical growth patterns of infants born to narcotic dependent mothers (INDM) over a 12 months period and, if possible, to relate the growth to drug taking patterns during pregnancy.
Methodology: The growth of a cohort of 43 INDM was measured during the first 12 months of life. Weight and length measurements were compared with percentile charts and converted to Z scores. Questionnaire data about drug taking practices, demographic variables and the neonatal period (including withdrawal scores) were obtained.
Results: Twenty-four (55.8%) of INDM had evidence of neonatal drug withdrawal requiring treatment with phenobarbitone. At birth, Z scores for weight and length indicated relative intrauterine growth retardation. By 12 months, there had been some catch up growth, but Z scores for weight and length were still below zero. Persistent weight retardation at 12 months was correlated with methadone dosage during pregnancy, but not the need for phenobarbitone therapy.
Conclusions: The growth patterns of INDM in the first 12 months of life indicated that at birth there was evidence of intrauterine growth retardation, but by 12 months the growth was little different from the rest of the community. There appears to be some influence of narcotic agents taken while pregnant on subsequent growth of INDM. 相似文献
Methodology: The growth of a cohort of 43 INDM was measured during the first 12 months of life. Weight and length measurements were compared with percentile charts and converted to Z scores. Questionnaire data about drug taking practices, demographic variables and the neonatal period (including withdrawal scores) were obtained.
Results: Twenty-four (55.8%) of INDM had evidence of neonatal drug withdrawal requiring treatment with phenobarbitone. At birth, Z scores for weight and length indicated relative intrauterine growth retardation. By 12 months, there had been some catch up growth, but Z scores for weight and length were still below zero. Persistent weight retardation at 12 months was correlated with methadone dosage during pregnancy, but not the need for phenobarbitone therapy.
Conclusions: The growth patterns of INDM in the first 12 months of life indicated that at birth there was evidence of intrauterine growth retardation, but by 12 months the growth was little different from the rest of the community. There appears to be some influence of narcotic agents taken while pregnant on subsequent growth of INDM. 相似文献