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141.
BACKGROUND: Clinical observations indicate that patients with Alzheimer's disease show a greater susceptibility to infections. One possible explanation is that this predisposition is due to alterations in their immune system. OBJECTIVE: To investigate this assumption, pro- and anti-inflammatory cytokines, as well as the phagocytic activity and superoxide anion generation was examined in aged individuals with and without Alzheimer's disease. METHODS: The production of IL-1beta, IL-2, IL-6, TNFalpha and IL-10 by peripheral blood mononuclear cells from 12 patients with Alzheimer's disease was compared with that of 12 age-matched individuals without any signs of dementia and 12 middle-aged healthy volunteers who served as an additional control. The engulfing capacity of the phagocytic cells was detected by counting cells containing latex beads and the number of particles internalized by each individual cell. RESULTS: The secretion of IL-2 was markedly low in the demented patients, compared with both elderly and middle-aged subjects. IL-1beta and TNFalpha production was similar in the individuals of the 3 groups. The production of IL-6 and IL-10 was significantly lower when compared to that of the middle-aged, but did not differ between the elderly patients with and without dementia. The phagocytic function of both polymorphonuclear cells and monocytes was decreased in individuals of the elderly groups with a low number of engulfed latex particles by each individual polymorphonuclear cell. The production of superoxide anions was increased only by monocytes from the elderly groups. CONCLUSIONS: The results suggest that although the impaired immune function in patients with Alzheimer's disease is related to the aging process, the significant low IL-2 production in these patients may play a role in their increased susceptibility to infections. 相似文献
142.
143.
Shalev H Avraham GP Hershkovitz R Levy A Sheiner E Levi I Tamary H 《European journal of haematology》2008,81(4):317-321
Objectives: Congenital dyserythropoietic anemia type I (CDA I) is a rare inherited disease characterized by moderate to severe macrocytic anemia and abnormal erythroid precursors with nuclear chromatin bridges and spongy heterochromatin. Moderate to severe maternal anemia is a recognized independent risk factor for low birth weight (LBW) and complicated delivery. The aim of the study was to review the outcome of pregnancies in women with CDA I. Methods: The clinical and laboratory records of 28 spontaneous pregnancies in six Bedouin women with CDA I were reviewed. The results were compared with findings from a retrospective review of a large population‐based registry including all pregnancies in Bedouin women during the same 15‐yr period. Results: Eighteen pregnancies in women with CDA I (64%) were complicated. One pregnancy was aborted spontaneously in the first trimester and one resulted in a non‐viable fetus (stillborn at 26 wk). Cesarean section (CS) was performed in 10 pregnancies (36%). Eleven of the 26 newborns (42%) had a LBW: six were born prematurely and five were small for gestational age. The odds ratio for CS in women with CDA I compared with healthy Bedouin women was 4.5 [95% confidence interval (CI) 1.2–10.3], and for a LBW infant, 5.5 (95% CI 2.4–12.3). Careful follow‐up was associated with significantly better fetal outcome (P = 0.05). Conclusions: Pregnancies in women with CDA I are at high risk for delivery‐related and outcome complications. To improve fetal outcome, women with CDA I should be carefully monitored during pregnancy. 相似文献
144.
The use of the hydrodynamic HBV animal model to study HBV biology and anti-viral therapy. 总被引:1,自引:0,他引:1
Mali Ketzinel-Gilad Arie Zauberman Ofer Nussbaum Yariv Shoshany Ofer Ben-Moshe Orit Pappo Yaakov Felig Ehud Ilan Hanna Wald Shlomo Dagan Eithan Galun 《Hepatology research》2006,34(4):228-237
A simple reproducible and versatile small animal model for hepatitis B virus (HBV) infection is still unavailable. We have generated a simple transient liver-targeted transgenic mouse. Hydrodynamics tail vein injection of a head-to-tail dimer of adw HBV genome (pHBVadwHTD) into immunocompetent mice generated HBsAg and HBeAg expression in both serum and hepatocytes, followed by seroconversion. The injection of pHBVadwHTD into SCID mice generated prolonged HBsAg and HBeAg antigenemia and HBV viremia. Our results demonstrate that hydrodynamic injection of naked DNA could support the generation of HBV particles. We used this model for the assessment of anti-viral agents. Administration of our human monoclonal antibodies, HBV-Ab17(XTL) and HBV-Ab19(XTL), as well as Lamivudine (3TC) treatment suppressed HBV viremia. The model presented herein supports long and stable expression of HBV and will enable determination of various biological questions related to HBV life cycle, mutants and could enhance the development of anti-viral reagents. 相似文献
145.
Hanna HA Raad II Hackett B Wallace SK Price KJ Coyle DE Parmley CL;M.D. Anderson Catheter Study Group 《Chest》2003,124(3):1030-1038
OBJECTIVE: To evaluate the impact of using central venous catheters (CVCs) impregnated with the combination of minocycline and rifampin on nosocomial bloodstream infections (BSIs), morbidity, and mortality in cancer patients in the ICU. DESIGN: Prospective surveillance study consisting of the following two time periods: September 1997 through August 1998 (ie, fiscal year [FY] 1998); and from September 1998 through August 1999 (ie, FY 1999). SETTING: ICUs of a tertiary care hospital in Houston, TX. PATIENTS: Cancer patients in the medical ICU (MICU) and surgical ICU (SICU). INTERVENTIONS: ICUs started using CVCs impregnated with the minocycline-rifampin combination at the beginning of FY 1999. Measurements and main results:The rates of nosocomial BSIs and other patients' characteristics were compared for the two study periods to determine the impact of using the impregnated catheters in the ICU. Patients' characteristics, including antibiotic use, were comparable for the two study periods in both the MICU and the SICU. The rate of nosocomial BSIs in the MICU unit decreased from 8.3 to 3.5 per 1,000 patient-days (p < 0.01), and decreased in the SICU from 4.8 to 1.3 per 1,000 patient-days (p < 0.01) in FY 1999. Nosocomial vancomycin-resistant enterococcus (VRE) bacteremia also decreased significantly (p = 0.004). Length of stay in the MICU and SICU significantly decreased in FY 1999 (p < 0.01 and p = 0.03, respectively). The duration of hospitalization decreased for MICU and SICU patients (p = 0.06 and p < 0.01, respectively). The rate of catheter-related infections decreased from 3.1 to 0.7 per 1,000 patient-days in FY 1999 (p = 0.02). The decrease in infections resulted in net savings of at least $1,450,000 for FY 1999. CONCLUSIONS: The use of antibiotic-impregnated CVCs in the MICU and SICU was associated with a significant decrease in nosocomial BSIs, including VRE bacteremia, catheter-related infections, and lengths of hospital and ICU stays. 相似文献
146.
Siński M Lewandowski J Abramczyk P Nowosad H Grzelak-Szafrańiska H 《Polskie Archiwum Medycyny Wewn?trznej》2005,114(2):755-760
Short acting nitrates are commonly used to prevent the anginal pain. The purpose of the study was to compare antianginal efficacy of Pentaerythritol compositum (20 mg of pentaerythritol tetranitrate and 0.5 mg of nitroglicerine) and 0,5 mg of nitroglycerine. Twenty patients aged 45-75 years with stable angina were enrolled. Antianginal effectiveness was evaluated during treadmill test. Time to ischemic pain and/or electrocardiographic parameters of ischemia were measured. It was found that Pentaerythritol compositum was superior to nitroglycerine in preventing angina with the difference disappearing 60 minutes after drug administration. Both drugs were well tolerated. Achieved results show that Pentaerythritol compositum can be effective as antianginal drug in patients with stable angina. 相似文献
147.
Pytkowski M Jankowska A Kraska A Sterliński M Kowalik I Krzyzanowski W Szwed H 《Polskie Archiwum Medycyny Wewn?trznej》2004,111(6):703-707
Aim of this prospective study was to assess quality of life (QoL), left ventricular (LV) function and exercise performance in two groups of patients (pts) with atrial fibrillation (Af) treated with: radiofrequency catheter ablation (RFA) and antiarrhythmic drugs (AA). Between 1996 and 2000 - 74 patients, 28 women, with drug refractory Af were enrolled by clinical indications for two modes of therapy: RFA and AA. RFA group consisted of 38 pts, 63.7 +/- 11.5 years old: 28 pts with RF AV Node ablation and pacemaker implantation (PI) and 10 pts with AV Node modification or right atrial isthmus RF ablation due to Af conversion to atrial flutter (Aflu) during medical therapy. AA group consisted of 36 pts, aged 59.7 +/- 13.8 years. Patients from RFA group suffered significantly more serious diseases than pts from AA group. No significant (sign.) differences between two groups were found in age, gender, arrhythmia history and number of AA taken. Pts were analyzed before entry, after 3 and 12 months of follow-up (3 mo. FU, 12 mo. FU) with following indices: LV function (Echo: EF & FS), exercise performance (treadmill test), QoL questionnaires, number of hospital admissions connected to arrhythmia or procedures (RFA & PI), number of AA drugs taken in RFA group. RFA group: Two deaths occurred due to end stage respiratory insufficiency (COPD), one pt required reposition of pacemaker lead. AA group: 3 pts required RFA due to uncontrolled Af/Aflu (AV Node ablation with PI - 1 pt, right atrial isthmus ablation - 2 pts). Analysis of two patients groups: LV function: Sign. improvement (EF & FS) in both groups in 12 mo. FU; Exercise performance: no sign. changes in 3 and 12 mo. FU. QoL: Arrhythmia scale: 3 mo. FU sign. reduction in both groups; 12 mo. FU reduction in RFA group only; Anxiety scale: 3 and 12 mo. FU sign. reduction of anxiety level in RFA group; Exercise and activity scales: 3 and 12 mo. FU sign. improvement in RFA group. During 3 and 12 mo. FU sign. less pts from RFA group required hospital admission versus pts from AA group. Sign. reduction in AA was noted in RFA group. Patients with symptomatic Af treated with RFA benefit from this kind of therapy more than patients treated with AA. Quality of life improvement visible in short term observation in patients from RFA group is still present after one year observation. Improvement in LV function is observed after one year in both groups of pts with Af. 相似文献
148.
149.
Hardcastle Cheshire Hausman Hanna K. Kraft Jessica N. Albizu Alejandro O’Shea Andrew Boutzoukas Emanuel M. Evangelista Nicole D. Langer Kailey Van Etten Emily J. Bharadwaj Pradyumna K. Song Hyun Smith Samantha G. Porges Eric DeKosky Steven T. Hishaw Georg A. Wu Samuel S. Marsiske Michael Cohen Ronald Alexander Gene E. Woods Adam J. 《Age (Dordrecht, Netherlands)》2022,44(2):1011-1027
GeroScience - Prior randomized control trials have shown that cognitive training interventions resulted in improved proximal task performance, improved functioning of activities of daily living,... 相似文献
150.
Päivä H Laakso J Laine H Laaksonen R Knuuti J Raitakari OT 《Journal of the American College of Cardiology》2002,40(7):1241-1247
OBJECTIVE: The goal of this study was to examine the relationship between plasma asymmetric dimethylarginine (ADMA) level and hyperemic myocardial blood flow (MBF) in subjects with borderline hypertension (BHT) and familial hypercholesterolemia (FH). METHODS: Asymmetric dimethylarginine is an endogenous competitive inhibitor of nitric oxide synthase that may modulate vascular function.We measured plasma ADMA levels and myocardial flow in 77 young men (mean age 35 +/- 5 years), including 47 healthy controls, 16 men with BHT, and 14 men with FH. Basal and dipyridamole-induced myocardial flow was measured using positron emission tomography. Plasma ADMA levels were measured using high-pressure liquid chromatography. RESULTS: Asymmetric dimethylarginine levels were significantly elevated in the BHT group compared with controls (0.59 +/- 0.13 micromol/l vs. 0.43 +/- 0.12 micromol/l, p < 0.001), and they had significantly lower dipyridamole flow (2.85 +/- 1.20 ml/min/g vs. 3.69 +/- 1.68 ml/min/g, p < 0.05). In a multivariate regression model adjusted for the study group, dipyridamole flow was inversely associated with ADMA (p < 0.05), age (p < 0.05), and apolipoprotein B concentration (p < 0.05). CONCLUSIONS: We conclude that plasma ADMA concentration is related to dipyridamole-induced vasodilatory function in young men, independently of blood pressure elevation and hypercholesterolemia. Subjects with BHT have significantly increased plasma ADMA levels, which may partly explain the impaired hyperemic MBF in this condition. 相似文献