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991.
It has been shown that only a small fraction of CD4+ T cells are infected with human immunodeficiency virus type 1 (HIV-1) in vivo, particularly early in the course of infection. An even smaller proportion of cells have been shown to be expressing virus. Recent studies suggest that plasma viremia in asymptomatic HIV-infected individuals, representing active viral replication, is more common than was previously believed (range 23-100% of patients). To determine the in vivo state of HIV expression, samples of peripheral blood of 49 HIV-infected individuals at all stages of disease were examined. All subjects were positive for viral DNA by standard polymerase chain reaction (PCR), and a modified PCR was utilized to detect HIV-specific mRNAs (gag, major splice junction, env, and tat/rev). Patient's plasma was also assayed for p24 antigen and viremia. The results were as follows: (formula: see text) Overall, the findings suggest that active viral expression occurs at all stages of HIV infection. In particular, the presence of gag mRNA was determined in only 2 of 14 patients with T4% greater than 30% but in 20 of 35 patients with T4% less than or equal to 30% (p less than 0.05), demonstrating a direct association between the presence of message for a structural protein, and more advanced immunosuppression. Determination of the expression of certain HIV-specific messages from within a patient's cells adds a new dimension to understanding the pathogenesis of HIV infection. The presence of HIV-specific mRNAs, and in particular gag message, in many healthy seropositives may further argue for early initiation of antiviral therapy.  相似文献   
992.
OBJECTIVE: A common G/T substitution at an Sp1 binding site in intron 1 of the COL1A1 gene has been reported to be associated with reduced bone mineral density and increased risk of osteoporotic fracture. The purpose of this study was to examine whether there is an association between COL1A1 Sp1 polymorphism and radiographic osteoarthritis (OA) of the hip in elderly women in the Study of Osteoporotic Fractures. METHODS: Radiographic hip OA status of subjects was defined by the presence of 1 of the following criteria in either hip: a joint space narrowing (JSN) score of >/=3, a Croft summary grade of >/=3, or both definite (score >/=2) osteophytes and JSN in the same hip. Cases of radiographic OA of the hip were further subdivided into those with JSN score >/=3 and those with a femoral osteophyte score >/=2 and JSN score /=3), and 131 (23%) had moderate or moderate-to-severe femoral osteophytosis (score >/=2). There was no association of the T/T genotype with either radiographic hip OA or radiographic hip OA characterized by osteophytosis. For radiographic OA of the hip characterized by moderate-to-severe JSN, the odds of disease were significantly reduced among subjects with the T/T compared with the G/G genotype (OR 0.30, 95% CI 0.11-0.81, P = 0.02) and did not change after adjustment for potential confounders (OR 0.36, 95% CI 0.13-0.99, P = 0.048). CONCLUSION: The T/T genotype of the COL1A1 Sp1 polymorphism was associated with a reduced risk of radiographic OA of the hip characterized by JSN. This association should be confirmed in other populations to determine if mechanistic studies are warranted.  相似文献   
993.
Acromegaly is associated with increased cardiovascular risk. Although conventional risk factors such as glucose intolerance, hypertension, and dyslipidemia probably contribute, there may also be direct effects of GH/IGF-I excess on the vasculature. To study the effects of GH excess on the vasculature, we have assessed arterial stiffness in acromegalic subjects with and without active disease and have investigated the effects of Sandostatin LAR (OCT-LAR) on vascular function. Sixteen normotensive subjects with acromegaly (10 males and 6 females) and 8 healthy controls were studied. Of the acromegalic subjects, eight had active disease (group A), and eight were cured (GH < 2.5 mU/liter; group B). The three groups were age, sex, and blood pressure matched. Group A subjects were restudied after 3 and 6 months of OCT-LAR therapy. Arterial stiffness was assessed by analyzing central arterial pressure waveforms derived from measured radial artery waveforms. This allowed determination of the augmentation of central pressure and the augmentation index. Lipids, glucose, and IGF-I were also measured. Comparing the three groups (ANOVA; mean +/- SD), the augmentation index was higher in group A (28 +/- 12 vs. 12 +/- 13%; P < 0.01) but not in group B (22 +/- 7 vs. 12 +/- 13%; P = 0.60), compared with controls. IGF-I was higher in group A (50.3 +/- 21.2 nmol/liter; P < 0.01), compared with group B (22.5 +/- 8.9 nmol/liter) and controls (19.5 +/- 5.3 nmol/liter). On regression analysis, IGF-I concentration was identified as a strong independent predictor of the augmentation index (beta = 0.50; P = 0.007). There were no significant differences in aortic systolic pressure, aortic diastolic pressure, lipids, or glucose. Compared with baseline, OCT-LAR treatment resulted in a lowering of augmentation index at 3 months (20 +/- 15 vs. 28 +/- 12%; P < 0.05), but at 6 months (24 +/- 16%; P = 0.21) there was no significant change. IGF-I was reduced from 50.3 +/- 21.2 nmol/liter at baseline to 31.4 +/- 13.2 nmol/liter at 3 months (P < 0.05) and 26.6 +/- 15.8 nmol/liter at 6 months (P < 0.05). In conclusion, acromegaly is associated with changes in the central arterial pressure waveform, suggesting large artery stiffening. This may have important implications for cardiac morphology and performance in acromegaly as well as increasing the susceptibility to atheromatous disease. Large artery stiffness is reduced in cured acromegaly and partially reversed after pharmacological treatment of active disease.  相似文献   
994.
995.
We report the results of a study in previously untreated advanced stage patients with follicular lymphoma (FL) who underwent uniform induction chemotherapy with cyclophosphamide, doxorubicin, vincristine, prednisone (CHOP) followed by myeloablative therapy and anti-B-cell monoclonal antibody purged autologous bone marrow transplantation (ABMT). Eighty-three patients with previously untreated, low-grade FL were enrolled. After CHOP induction, only 36% achieved complete remission (CR) and 77 patients underwent ABMT. Before BM harvest, 70 patients had a known t(14;18), as determined by polymerase chain reaction (PCR), and all remained PCR positive in the BM at harvest. After ABMT, the disease-free survival (DFS) and overall survival are estimated to be 63% and 89% at 3 years, respectively, with a median follow-up of 45 months. Patients whose BM was PCR negative after purging experienced significantly longer freedom from recurrence (FFR) than those whose BM remained PCR positive (P = .0006). Continued PCR negativity in follow-up BM samples was also strongly predictive of continued CR. This study suggests that a subset of patients with advanced FL may experience prolonged clinical and molecular remissions following high-dose ablative therapy, although longer follow-up will be necessary to determine potential impact on overall survival.  相似文献   
996.
Patients with plasma viral RNA >50,000 copies/mL, despite a protease-inhibitor regimen, received abacavir, amprenavir, and efavirenz to assess efavirenz-amprenavir drug interactions and to evaluate safety and antiviral response. Patients first received amprenavir with abacavir and other nucleoside analogs. Amprenavir levels were measured before and after adding efavirenz. Patients then received a second protease inhibitor. There was evidence of genotypic and phenotypic resistance at study entry. No patient had study drugs discontinued because of toxicity. Efavirenz decreased the steady-state area under the curve, maximum plasma concentration, and minimum plasma concentration of amprenavir by 24%, 33%, and 43%, respectively. Three of 10 patients had >1.5 log10 viral response to abacavir and amprenavir. All 8 patients who added efavirenz had >0.5 log10 decline in viral load, and this response lasted >24 weeks for 3 of the patients. A combination regimen that included abacavir, amprenavir, and efavirenz was well tolerated and had sustained activity in some patients. Concomitant efavirenz therapy decreases amprenavir concentrations.  相似文献   
997.
Estrogen receptors (ERs) are expressed in numerous organs, although only a few organs are considered classical targets for estrogens. We have completed a systematic survey of estrogen regulation of approximately 10,000 genes in 13 tissues from wild-type and ERbetaKO mice treated sc with vehicle or 17beta-estradiol (E2) for 6 wk. The uterus and pituitary had the greatest number of genes regulated by E2, whereas the kidney had the third largest number of regulated genes. In situ hybridizations localized E2 regulation in the kidney to the juxtamedullary region of the cortex in both the mouse and rat. The ED(50) for gene inductions in the kidney was 3 micro g/kg.d, comparable with the 2.4 micro g/kg.d ED(50) for c-fos induction in the uterus. E2 regulations in the kidney were intact in ERbetaKO mice, and the ERalpha-selective agonist propylpyrazole triol acted similarly to E2, together suggesting an ERalpha-mediated mechanism. Several genes were induced within 2 h of E2 treatment, suggesting a direct activity of ERalpha within the kidney. Finally, the combination of the activation function (AF)1-selective agonist tamoxifen plus ERalphaKO(CH) mice expressing an AF1-deleted version of ERalpha allowed delineation of genes with differing requirements for AF1 or AF2 activity in the kidney.  相似文献   
998.
999.
The biological mechanisms leading to periprosthetic osteolysis involve both chemokines and the monocyte/macrophage cell lineage. Whether MCP-1 plays a major role in macrophage recruitment in the presence of wear particles is unknown. We tested two hypotheses: (1) that exogenous local delivery of MCP-1 induces systematic macrophage recruitment and (2) that blockade of the MCP-1 ligand-receptor axis decreases macrophage recruitment and osteolysis in the presence of ultra high molecular weight polyethylene (UHMWPE) particles. Six groups of nude mice were used. We used non-invasive imaging to assay macrophage recruitment and osteolysis. A murine macrophage cell line and primary wild type and CCR2 knockout murine macrophages were used as the reporter cells. Particles were infused into the femoral canal. Bioluminescence and immunohistochemical staining were used to confirm the migration of reporter cells. Locally infused MCP-1 induced systemic macrophage trafficking to bone. Injection of MCP-1 receptor antagonist significantly decreased reporter cell recruitment to bone infused with UHMWPE particles and decreased osteolysis. Systemic migration of reporter cells to infused particles was decreased when the reporter cells were deficient in the CCR2 receptor. Interruption of the MCP-1 ligand-receptor axis appears to be a viable strategy to mitigate trafficking of macrophages and osteolysis due to UHMWPE particles.  相似文献   
1000.
Contemporary multimodal anesthesia regimens allow the performance of unicompartment knee arthroplasty (UKA) on an outpatient basis. Our initial pilot experience is presented using a continuous femoral nerve block as an adjunct for 24 patients classified as American Society of Anesthesiology class 1 (14 men, 10 women; median age, 56 years; range, 46-72 years). After minimally invasive UKA, patients documented their pain and oral medication use while at home for the first 5 days. Adverse events, medication adverse effects, and the amount of infused ropivacaine were recorded. Median pain scores for the first 3 days were 1, 2, and 2 (at rest) and 4, 5, and 3 (during physical therapy). Eighteen patients (75%) required less than 4 mg oral hydromorphone/d. Of the 18, 10 (42%) did not require supplemental oral opioids. The median catheter use was 3 days. Our results suggest that with careful patient selection and adequate teaching, continuous femoral nerve blocks may be used as part of a multimodal pain regimen to assist the delivery of outpatient UKA with high patient satisfaction.  相似文献   
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