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21.
PURPOSE: To determine the safety, immunogenicity, and clinical response to an allogeneic tumor vaccine for non-small-cell lung cancer, we conducted a phase I trial in patients with advanced metastatic disease. PATIENTS AND METHODS: We treated 19 patients with a vaccine based on an adenocarcinoma line (AD100) transfected with B7.1 (CD80) and HLA A1 or A2. Patients were vaccinated intradermally with 5 x 10(7) cells once every 2 weeks. Three vaccinations represented one course of treatment. If patients had complete response, partial response, or stable disease, they continued with the vaccinations for up to three courses (nine vaccinations). Immune response was assessed by a change between pre-study and postvaccination enzyme-linked immunospot frequency of purified CD8 T-cells secreting interferon-gamma in response to in vitro challenge with AD100. RESULTS: Four patients experienced serious adverse events that were unrelated to vaccine. Another four patients experienced only minimal skin erythema. All but one patient had a measurable CD8 response after three immunizations. The immune response of six surviving, clinically responding patients shows that CD8 titers continue to be elevated up to 150 weeks, even after cessation of vaccination. Overall, one patient had a partial response, and five had stable disease. Median survival for all patients is 18 months (90% CI, 7 to 23 months), with corresponding estimates of 1-year, 2-year, and 3-year survival of 52%, 30%, and 30%, respectively. HLA matching of vaccine, age, sex, race, and pathology did not bear a significant relation to response. CONCLUSION: Minimal toxicity and good survival in this small population suggest clinical benefit from vaccination.  相似文献   
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Long-term effects of angiotensin-converting enzyme inhibition and metabolic control in hypertensive type 2 diabetic patients. BACKGROUND: In hypertensive type 2 diabetic patients, treatment with angiotensin-converting enzyme (ACE) inhibitors is associated with a lower incidence of cardiovascular events than those treated with calcium channel-blocking agents. However, the long-term renal effects of ACE inhibitors in these patients remain inconclusive. In 1989, we commenced a placebo-controlled, double-blind, randomized study to examine the anti-albuminuric effects of enalapril versus nifedipine (slow release) in 102 hypertensive, type 2 diabetic patients. These patients have been followed up for a mean trial duration of 5.5 +/- 2.2 years. We examined the determinants, including the effect of ACE inhibition on clinical outcomes in these patients. METHODS: After a six-week placebo-controlled, run-in period, 52 patients were randomized double-blind to receive nifedipine (slow release) and 50 patients to receive enalapril. After the one-year analysis, which confirmed the superior anti-albuminuric effects of enalapril (-54%) over nifedipine (+11%), all patients were continued on their previously assigned treatment with informed consent. They were subdivided into normoalbuminuric (N = 43), microalbuminuric (N = 34), and macroalbuminuric (N = 25) groups based on two of three 24-hour urinary albumin excretion (UAE) measurements during the run-in period. Renal function was shown by the 24-hour UAE, creatinine clearance (CCr), and the regression coefficient of the yearly plasma creatinine reciprocal (beta-1/Cr). Clinical endpoints were defined as death, cardiovascular events, and/or renal events (need for renal replacement therapy or doubling of baseline plasma creatinine). RESULTS: In the whole group, patients treated with enalapril were more likely to revert to being normoalbuminuric (23.8 vs. 15.4%), and fewer of them developed macroalbuminuria (19.1 vs. 30.8%) compared with the nifedipine-treated patients (P < 0.05). In the microalbuminuric group, treatment with enalapril (N = 21) was associated with a 13.0% (P < 0.01) reduction in 24-hour UAE compared with a 17.3% increase in the nifedipine group (N = 13). In the macroalbuminuric patients, enalapril treatment (N = 11) was associated with stabilization compared with a decline in renal function in the nifedipine group, as shown by the beta-1/Cr (0.65 +/- 4.29 vs. -1.93 +/- 2.35 1/micromol x 10-3, P < 0.05) after adjustment for baseline values. Compared with the normoalbuminuric and microalbuminuric patients, those with macroalbuminuria had the lowest mean CCr (75.5 +/- 24.1 vs. 63.5 +/- 21.3 vs. 41.9 +/- 18.5 mL/min, P < 0.001) and the highest frequency of clinical events (4.7 vs. 5.9 vs. 52%, P < 0. 001). On multivariate analysis, beta-1/Cr (R2 = 0.195, P < 0.001) was independently associated with baseline HbA1c (beta = -0.285, P = 0.004), whereas clinical outcomes (R2 = 0.176, P < 0.001) were independently related to the mean low-density lipoprotein cholesterol (beta = 2.426, P = 0.018), high-density lipoprotein cholesterol (beta = -8.797, P = 0.03), baseline UAE (beta = 0.002, P = 0.04), and mean CCr during treatment (beta = -0.211, P = 0.006). CONCLUSION: In this prospective cohort analysis involving 102 hypertensive, type 2 diabetic patients with varying degrees of albuminuria followed up for a mean duration of five years, we observed the importance of good metabolic and blood pressure control on the progression of albuminuria and renal function. Treatment with enalapril was associated with a greater reduction in albuminuria than with nifedipine in the entire patient group, and especially in those with microalbuminuria. In the macroalbuminuric patients, the rate of deterioration in renal function was also attenuated by treatment with enalapril.  相似文献   
23.
The reductive metabolism of the rat carcinogen 4-(5-nitro-2furyl)thiazole (NFT) to 1-4-thiazolyl)-3-cyano-1-propanone (TCP) is reported. Formation of TCP from NFT involved furan ring fission. This could have occurred through involvement of either aminofuran or N-hydroxylaminofuran as precursors. To examine if 4-(5-amino-2-furyl)thiazole is a precursor for TCP, a stable model compound, 4-(5-acetylamino-2-furyl)thiazole (AAFT), was prepared and subjected to enzymatic deacetylation, using rat liver tissue homogenates. AAFT was synthesized by catalytic hydrogenation of NFT with 5% palladium on activated carbon, followed by acetylation with acetic anhydride. AAFT, a white crystalline powder, melted at 168–170°, had an extinction coefficient of 17.9 mM?1 cm?1 at 293 nm in ethyl acetate, and exhibited spectroscopic and mass spectral characteristics consistent with the assigned structure. Incubation with rat liver 10,000 g supernatant preparations resulted in the biotransformation of AAFT as evidenced by a decrease in absorption at 290 nm. Incubation of 14C-labeled AAFT followed by extraction with chloroform-diethyl ether (1:1) resulted in the recovery of a major portion (56%) of the radioactivity in the organic phase when the label was at the 2-position of the thiazole ring, while the major amount (82%) of radioactivity was recovered in the aqueous phase when the 1-14C-acetyl group was labeled. The radioactivity from the aqueous phase was extractable into the organic phase following acidification to pH 1, an observation consistent with deacetylation. Furthermore, the deacetylation product exhibited a mass spectrum, and retention times in gas and high pressure liquid chromatography, similar to those of synthetic TCP. These data establish 4-(5-amino-2-furyl)thiazole, derived from AAFT by deacetylation, as a precursor for TCP.  相似文献   
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OBJECTIVE: To evaluate the utility of the tuberculin skin test (TST) in detecting latent and active tuberculosis (TB) among human immunodeficiency virus (HIV) infected patients in South India. DESIGN: TSTs and CD4 counts were collected from 631 HIV-infected individuals without active TB and 209 antiretroviral and anti-tuberculosis treatment-na?ve HIV-infected patients with TB. We calculated the proportion of TST-positive individuals, as well as the sensitivity, specificity, positive predictive value (PPV) and negative predictive value of TST in the diagnosis of TB. RESULTS: Among subjects without active TB, 28% with a CD4 count <100 cells/microl vs. 43% of the total cohort had a TST >5 mm (P = 0.14), while the proportions with induration >10 mm were 14% vs. 36%, respectively (P < 0.01). Among those with active TB, using a 5 mm cut-off, the sensitivity was 42% for those with CD4 counts <200 cells/mul compared to 70% for those with CD4 counts >or=200 cells/microl (P < 0.001). The PPV for detecting active TB was 29%. CONCLUSIONS: TST is a poor predictor of both latent and active TB in HIV-infected individuals in TB endemic countries. Programmes offering treatment for latent TB should consider including all HIV-positive patients regardless of TST status, or use other indicators, such as CD4 count.  相似文献   
28.
We sought to determine the influence of vessel diameter on the efficacy of distal protection devices during saphenous vein graft intervention. From the Filterwire EX Randomized Evaluation trial, in which patients who underwent saphenous vein graft stenting were randomized to distal protection with the GuardWire or FilterWire EX, outcomes in 572 patients were examined in vessel size tertiles. The 30-day composite incidence of major adverse cardiac events (MACEs) increased with vessel size and was 6.9%, 9.7%, and 14.9% in the smallest, middle, and largest tertiles, respectively (p = 0.04). MACE rates were relatively vessel size independent for the GuardWire but increased steadily with vessel size with the FilterWire EX. In the smallest tertile, MACEs were reduced by 71% with the FilterWire EX compared with the GuardWire (p = 0.05), with the devices showing similar event rates in the other tertiles.  相似文献   
29.
An important histological difference between normal, uninjured dermis and scar tissue such as that found in keloid scars is the pattern (morphological architecture) in which the collagen is deposited and arranged. In the uninjured dermis, collagen bundle architecture appears randomly organized (or in a basket weave formation), whereas in pathological conditions such as keloid scar tissue, collagen bundles are often found in whorls or in a hypotrophic scar collagen is more densely packed in a parallel configuration. In the case of skin, a scar disables the dermis, leaving it weaker, stiff and with a loss of optimal functionality. The absence of objective and quantifiable assessments of collagen orientation is a major bottleneck in monitoring progression of scar therapeutics. In this article, a novel quantitative approach for analyzing collagen orientation is reported. The methodology is demonstrated using collagen produced by cells in a model scar environment and examines collagen remodeling post-TGFβ stimulation in vitro. The method is shown to be reliable and effective in identifying significant coherency differences in the collagen deposited by human keloid scar cells. The technique is also compared for analysing collagen architecture in rat sections of normal, scarred skin and tendon tissue. Results demonstrate that the proposed computational method provides a fast and robust way of analyzing collagen orientation in a manner surpassing existing methods. This study establishes this methodology as a preliminary means of monitoring in vitro and in tissue treatment modalities which are expected to alter collagen morphology.

A novel technique for the fast and robust quantification of collagen architecture following scarring.  相似文献   
30.
Tissue Doppler echocardiographic imaging (TDI) is a novel method for accurately evaluating ventricular function. Currently, scant data are available on the distribution of tissue Doppler indexes in healthy children in the age range of 1 to 18 years. The aims of this study were to assess the distribution of tissue Doppler indexes of systolic and diastolic ventricular function in healthy children, to assess the influence of age on these indexes, and to compare them with conventional Doppler indexes. A total of 151 consecutive children aged 1 to 18 years were enrolled in the study. Nine different (7 diastolic and 2 systolic) TDI parameters were assessed. Peak velocities of systolic and diastolic excursions of the mitral and tricuspid annuli were obtained from the apical 4-chamber view. Mean velocities of early diastolic recoil of mitral and tricuspid annuli were measured from the apical 4-chamber view. The mean velocity of early diastolic relaxation of the left ventricular posterior wall was measured in the parasternal long-axis view. Results showed a statistically significant difference in some of the TDI indexes among the different pediatric age groups. Most of the TDI indexes showed a very weak correlation with age. There was no significant correlation (p >0.05) between peak velocities of the early diastolic mitral inflow Doppler pattern (E wave) and the corresponding TDI index. In contrast, there was a significant (p <0.001) correlation between the corresponding Doppler indexes in the tricuspid annulus. We conclude that TDI is a valuable tool for assessing ventricular function, particularly diastolic function. Establishment of normative data for TDI in the pediatric age group should broaden the clinical applicability of this useful modality for assessing ventricular function.  相似文献   
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