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101.
A new mitral valve   总被引:1,自引:0,他引:1  
  相似文献   
102.
BACKGROUND: The ability to express genes with potential immunoregulatory capacity could reduce allograft rejection (AR). We examined the feasibility of transferring the viral interleukin-10 (vIL-10) gene into rat lungs by intra-bronchial instillation and the subsequent effects of delivered vIL-10 on acute lung AR. METHODS: First, the adenoviral beta-galactosidase vector (adv-beta-gal) particles were instilled into the airway of the rat lung and protein synthesis of beta-gal was examined by histochemical staining. Next, the ability of the adenoviral vIL-10 vector (adv-vIL-10) transfection to modify AR was examined in a highly histoincompatible rat lung transplant model (BN-->Lew). Donor left lungs were transfected with 3 x 10(8) pfu/0.3 mL of adv-vIL-10 (vIL-10 group) or adv-beta-gal (control group) 3 days before transplantation. On day 6 post-transplant, lung allografts were harvested and AR was graded histologically (stage 0-4). Several pathological categories of inflammation (perivascular, peribronchial, or peribronchiolar mononuclear infiltrates, edema, vasculitis, intraalveolar hemorrhage, and necrosis) were also examined and scored on a scale of 0-4 as previously described. RESULTS: A successful transgene protein synthesis by adv-beta-gal in alveolar epithelial cells and alveolar macrophages was confirmed by histochemical staining with X-gal. The vIL-10 group showed a trend toward an improved stage of AR (3.75 +/- 0.5 vs. 4.0 +/- 0), and also a decreased pathological scores for edema (3.5 +/- 0.6 vs. 4.0 +/- 0), intraalveolar hemorrhage (2.3 +/- 1.0 vs. 2.5 +/- 0.6) and necrosis (1.5 +/- 0.5 vs. 1.75 +/- 1.3) compared with the control group, however, the differences in any pathological scores between the two groups did not reach a statistical significance. CONCLUSIONS: 1. A successful transgene protein synthesis in alveolar epithelial cells was ensured by intra-bronchial instillation of an adenoviral vector encoding beta-galactosidase gene. 2. Transferring the vIL-10 gene into rat lungs by intra-bronchial instillation did not seem to reduce lung AR significantly, as opposed to the results of our previous experiments in a rat cardiac allograft model. This discrepancy may be explained by several potential factors including the immunogenecity of adenoviral vectors in conjunction with the nature of the lung more susceptible to immune response and inflammation.  相似文献   
103.
We evaluated D-penicillamine in the treatment of primary biliary cirrhosis. In a prospective double-blind trial, 26 patients received D-penicillamine (250 mg four times a day), and 26 received an identical placebo. Although the desired urinary excretion of copper was achieved in patients taking D-penicillamine, there was no improvement in survival or symptoms after 28 months. Serum bilirubin and alkaline phosphatase increased equally in both groups. Alanine and aspartate aminotransferases were lower in the D-penicillamine group, but serum albumin was also lower in this group. Liver histology worsened equally in both groups. Major side effects, some appearing more than 24 months after the start of treatment, occurred in 31 per cent of the patients receiving D-penicillamine. Less serious side effects occurred in an additional 46 per cent. We conclude that D-penicillamine at the dosage we used is not effective in the treatment of primary biliary cirrhosis and is associated with a high incidence of serious side effects.  相似文献   
104.
105.
Nitric oxide (NO) is synthesized from L-arginine by a family of enzymes known as the nitric oxide synthases (NOS). We have recently shown a NOS similar to constitutive brain NOS (bNOS) and endothelial NOS (ecNOS) to be present in spermatozoa. The aim of this study is to investigate NO production by human spermatozoa and the effects of stimulation and inhibition of NOS. This was carried out using the Iso-NO, an isolated NO meter and sensor, which provides rapid, accurate and direct measurements of NO. Semen samples with normozoospermic and asthenozoospermic profiles were prepared using a direct swim-up technique. Basal concentrations of NO and stimulated NO production were measured after exposure to the calcium ionophore (A23187; 0.01-10 microM) a potent activator of constitutive NOS. NO production in human spermatozoa was significantly increased by the addition of A23187 30 seconds after stimulation. Furthermore, this response was greatly diminished by pre-incubating the samples with competitive inhibitors of L-arginine, the substrate for NOS, before treatment with calcium ionophore. In the presence of N(G)-nitro-L-arginine methyl ester (L- NAME), N(G)-nitro-L-arginine (L-NA) or N(G)-methyl-L-arginine (L-NMMA; all at 10 microM), NO production was inhibited with a rank order of potency L-NAME > L-NMMA > L-NA which is in accordance with the inhibition of an endothelial type of constitutive NOS.   相似文献   
106.

Objective

People living with HIV infection are at increased risk for developing cardiovascular disease (CVD). Safe and effective interventions for lowering CVD risk in HIV infection are high priorities. We conducted a prospective, randomized, controlled study to evaluate whether a yoga lifestyle intervention improves CVD risk factors, virological or immunological status, or quality of life (QOL) in HIV‐infected adults relative to standard of care treatment in a matched control group.

Methods

Sixty HIV‐infected adults with mild–moderate CVD risk were assigned to 20 weeks of supervised yoga practice or standard of care treatment. Baseline and week 20 measures were: 2‐h oral glucose tolerance test with insulin monitoring, body composition, fasting serum lipid/lipoprotein profile, resting blood pressures, CD4 T‐cell count and plasma HIV RNA, and the Medical Outcomes Study Short Form (SF)‐36 health‐related QOL inventory.

Results

Resting systolic and diastolic blood pressures improved more (P=0.04) in the yoga group (−5 ± 2 and −3 ± 1 mmHg, respectively) than in the standard of care group (+1 ± 2 and+2 ± 2 mmHg, respectively). However, there was no greater reduction in body weight, fat mass or proatherogenic lipids, or improvements in glucose tolerance or overall QOL after yoga. Immune and virological status was not adversely affected.

Conclusion

Among traditional lifestyle modifications, yoga is a low‐cost, simple to administer, nonpharmacological, popular behavioural intervention that can lower blood pressure in pre‐hypertensive HIV‐infected adults with mild–moderate CVD risk factors.
  相似文献   
107.
Lipids constitute 70% of the myelin sheath, and autoantibodies against lipids may contribute to the demyelination that characterizes multiple sclerosis (MS). We used lipid antigen microarrays and lipid mass spectrometry to identify bona fide lipid targets of the autoimmune response in MS brain, and an animal model of MS to explore the role of the identified lipids in autoimmune demyelination. We found that autoantibodies in MS target a phosphate group in phosphatidylserine and oxidized phosphatidylcholine derivatives. Administration of these lipids ameliorated experimental autoimmune encephalomyelitis by suppressing activation and inducing apoptosis of autoreactive T cells, effects mediated by the lipids' saturated fatty acid side chains. Thus, phospholipids represent a natural anti-inflammatory class of compounds that have potential as therapeutics for MS.  相似文献   
108.
The St. Jude Medical valve is a bileaflet prosthesis with excellent hemodynamic characteristics, but the long-term surgical experience with this valve, its durability, and its biocompatibility are unknown. During a 10-year period from March 1978 to 1988, 690 prostheses (290 aortic, 252 mitral, and 74 double aortic-mitral) were inserted as the initial valve replacement substitute in 616 patients (mean age 63 years). Coronary atherosclerosis was present in 58%. Follow-up totaled 2031 patient-years (mean 3.3 years) and was 95% complete (32 lost). Early (30-day) mortality rates were 5.2%, 11.9%, and 8.1% after aortic, mitral, and double valve replacement; 5- and 9-year actuarial survival rates were 71% +/- 3% and 51% +/- 8%, 59% +/- 4% and 41% +/- 6%, and 69% +/- 6% and 47% +/- 15%, respectively. Deaths were associated with extensive coronary atherosclerosis (p less than 0.001), older age (p less than 0.001), advanced preoperative New York Heart Association functional class (p less than 0.05), and malignant ventricular arrhythmias (p less than 0.05). No structural failures have been observed. Embolism (40 events) occurred at a rate of 2.0%/pt-yr (2.3% aortic, 1.6% mitral, 2.0% double). There were six cases of valve thrombosis (0.3%/pt-yr; one fatal). Hemorrhage was the most frequent complication (2.6%/pt-yr); 13 (25%) of 52 events were fatal, accounting for 62% of all valve-related deaths. After the target prothrombin time ratio was lowered, the rate of hemorrhage decreased by 44% (2.7% to 1.5%/pt-yr), while the combined rate of embolism and valve thrombosis increased slightly (2.2% to 2.5%/pt-yr, a 14% change). In summary, the St. Jude Medical valve remains a durable valve substitute. Survival was strongly related to the presence of associated coronary atherosclerosis. The most common complication has been hemorrhage; a less intensive warfarin regimen may reduce hemorrhagic risk while maintaining thromboembolic protection.  相似文献   
109.

Background

Alzheimer's disease (AD), the most prevalent form of dementia, affects 6.5 million Americans and over 50 million people globally. Clinical, genetic, and phenotypic studies of dementia provide some insights of the observed progressive neurodegenerative processes, however, the mechanisms underlying AD onset remain enigmatic.

Aims

This paper examines late-onset dementia-related cognitive impairment utilizing neuroimaging-genetics biomarker associations.

Materials and Methods

The participants, ages 65–85, included 266 healthy controls (HC), 572 volunteers with mild cognitive impairment (MCI), and 188 Alzheimer's disease (AD) patients. Genotype dosage data for AD-associated single nucleotide polymorphisms (SNPs) were extracted from the imputed ADNI genetics archive using sample-major additive coding. Such 29 SNPs were selected, representing a subset of independent SNPs reported to be highly associated with AD in a recent AD meta-GWAS study by Jansen and colleagues.

Results

We identified the significant correlations between the 29 genomic markers (GMs) and the 200 neuroimaging markers (NIMs). The odds ratios and relative risks for AD and MCI (relative to HC) were predicted using multinomial linear models.

Discussion

In the HC and MCI cohorts, mainly cortical thickness measures were associated with GMs, whereas the AD cohort exhibited different GM-NIM relations. Network patterns within the HC and AD groups were distinct in cortical thickness, volume, and proportion of White to Gray Matter (pct), but not in the MCI cohort. Multinomial linear models of clinical diagnosis showed precisely the specific NIMs and GMs that were most impactful in discriminating between AD and HC, and between MCI and HC.

Conclusion

This study suggests that advanced analytics provide mechanisms for exploring the interrelations between morphometric indicators and GMs. The findings may facilitate further clinical investigations of phenotypic associations that support deep systematic understanding of AD pathogenesis.  相似文献   
110.
PURPOSE: Data on the efficacy of bilateral prophylactic mastectomy for breast cancer risk reduction in women with BRCA1 and BRCA2 (BRCA1/2) mutations are limited, despite the clinical use of this risk-management strategy. Thus, we estimated the degree of breast cancer risk reduction after surgery in women who carry these mutations. PATIENTS AND METHODS: Four hundred eighty-three women with disease-associated germline BRCA1/2 mutations were studied for the occurrence of breast cancer. Cases were mutation carriers who underwent bilateral prophylactic mastectomy and who were followed prospectively from the time of their center ascertainment and their surgery, with analyses performed for both follow-up periods. Controls were BRCA1/2 mutation carriers with no history of bilateral prophylactic mastectomy matched to cases on gene, center, and year of birth. Both cases and controls were excluded for previous or concurrent diagnosis of breast cancer. Analyses were adjusted for duration of endogenous ovarian hormone exposure, including age at bilateral prophylactic oophorectomy if applicable. RESULTS: Breast cancer was diagnosed in two (1.9%) of 105 women who had bilateral prophylactic mastectomy and in 184 (48.7%) of 378 matched controls who did not have the procedure, with a mean follow-up of 6.4 years. Bilateral prophylactic mastectomy reduced the risk of breast cancer by approximately 95% in women with prior or concurrent bilateral prophylactic oophorectomy and by approximately 90% in women with intact ovaries. CONCLUSION: Bilateral prophylactic mastectomy reduces the risk of breast cancer in women with BRCA1/2 mutations by approximately 90%.  相似文献   
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