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971.
Kamya MR Semitala FC Quinn TC Ronald A Njama-Meya D Mayanja-Kizza H Katabira ET Spacek LA 《African health sciences》2004,4(2):94-101
Introduction
Total Lymphocyte Count (TLC) has been found to be an inexpensive and useful marker for staging disease, predicting progression to AIDS and death and monitoring response to ART. However, the correlation between TLC and CD4 has not been consistent. Access to HAART is expanding in Kampala, Uganda, yet there are no published data evaluating the utility of TLC as inexpensive surrogate marker of CD4 cell count to help guide therapeutic decisions.Objective
To evaluate clinical illnesses and total lymphocyte count (TLC) as surrogate markers of the CD4 cell count in HIV infected persons being considered for ART.Methods
A total of 131 patients were enrolled and evaluated by clinical assessment, TLC and CD4 count. Clinical illnesses and TLC dichotomized at various cut-point values were used to determine the sensitivity, specificity, and positive and negative predictive values (PPV and NPV) for the diagnosis of CD4 count <200 cells/mm3 among 100 participants fulfilling criteria for WHO clinical stage 2 and 3.Results
A strong correlation was observed between TLC and CD4 (r = 0.73, p<0.0001). For all clinical syndromes, except pulmonary tuberculosis, the positive predictive values (PPV) for a CD4 count <200 cells/mm3 were high (>80%) but the negative predictive values (NPV) were low. Using the WHO recommended TLC cut-off of 1200 cells/mm3 to diagnose a CD4 less than 200 cells/mm3, the PPV was 100%, and the NPV was 32%.Conclusion
Our data showed a good correlation between TLC and CD4 cell count. However, the WHO recommended TLC cutoff of 1200 did not identify the majority of WHO stage 2 and 3 patients with CD4 counts less than 200 cells/mm3. A more rational use of TLC counts is to treat all patients with WHO stage 2 and 3 who have a TLC <1200 and to limit CD4 counts to patients who are symptomatic but have TLC of >1200. 相似文献972.
Antitumor immune response by CX3CL1 fractalkine gene transfer depends on both NK and T cells 总被引:6,自引:0,他引:6
Xin H Kikuchi T Andarini S Ohkouchi S Suzuki T Nukiwa T Huqun Hagiwara K Honjo T Saijo Y 《European journal of immunology》2005,35(5):1371-1380
The CX3C chemokine fractalkine (CX3CL1) exists as both a membrane-bound form promoting firm cell-cell adhesion and a soluble form chemoattracting leukocytes expressing its receptor CX3CR1. When adenoviral vector expressing mouse fractalkine (AdFKN) was transduced to the tumor cells, fractalkine was expressed as both membrane-bound form on the tumor cells and soluble form in the supernatant in vitro. Intratumoral injection of AdFKN (1 x 10(9)PFU/tumor) into C26 and B16F10 tumors resulted in marked reduction of tumor growth compared to control (C26: 86.5%, p<0.001; B16F10: 85.5%, p<0.001). Histological examination of tumor tissues revealed abundant infiltration of NK cells, dendritic cells, and CD8(+) T lymphocytes 3 and/or 6 days after treatment with AdFKN. Splenocytes from mice treated by AdFKN developed tumor-specific cytotoxic T cells, and thereby protected from rechallenging with parental tumor cells. Antitumor effects by AdFKN were completely abrogated in both NK cell-depleted mice and CD8(-/-) mice, and partially blocked in CD4(-/-) mice. These data indicated that fractalkine mediates antitumor effects by both NK cell-dependent and T cell-dependent mechanisms. This study suggests that fractalkine can be a suitable candidate for immunogene therapy of cancer because fractalkine induces both innate and adaptive immunity. 相似文献
973.
Summary Rats have been fed diets containing 24.2% coconut or corn oil or an equal mixture of each for 14–18 weeks. Half of the animals in each dietary group were exercised by running in motor-driven work wheels throughout the entire experimental period. During the final 10–14 weeks, these exercised animals ran continuously for 60 min at 1.0 mph or faster each day. Comparisons between sedentary groups revealed that hepatic cholesterol and excretion of digitonin precipitated sterols in the feces increased (P < 0.01) as the per cent of unsaturated fat (corn oil) in the ingested food increased. In contrast, total liver lipid decreased (P < 0.01) as the consumption of corn oil increased. No change in plasma cholesterol occurred in the sedentary rats in response to the three diets. Hepatic cholesterol of the exercised groups was significantly less (P < 0.05–P < 0.01) than that of their respective control groups (same diet). However, the group fed the corn oil diet had a significantly higher (P < 0.01) liver cholesterol after exercise than did the exercised group fed the coconut oil diet. Liver lipid was reduced (P < 0.01) by exercise in the corn oil and mixed corn-coconut oil fed groups. Plasma cholesterol and sterol excretion were unchanged by the exercise program.This investigation supported by Research Grant HE 08262 from the National Heart Institute, National Institutes of Health, U.S. Public Health Service. 相似文献
974.
目的:通过去除N端丝氨酸32/36磷酸化位点,获得人胎盘组织IκBα突变体(IκBαM)基因,构建其复制缺陷型重组腺病毒(AdIκBαM),并进行体外表达和活性检测。方法:PCR定点克隆IκBαM基因(203-1 003 bp),亚克隆至pShuttle和pGEM-T,进行PCR、双酶切、DNA测序和同源性分析。将重组质粒pShuttle-IκBαM中含CMV启动子、IκBαM cDNA和PolyA信号的表达单元定向插入Ad5腺病毒载体,构建成重组腺病毒AdIκBαM,再经脂质体介导共转染293细胞进行包装。Western blotting检测AdIκBαM在293细胞中蛋白表达情况,电泳迁移率实验观察AdIκBαM抑制佛波酯诱导的ECV304细胞核因子κB(NF-κB)激活的作用。结果:成功克隆长801 bp的新型IκBαM基因,与GenBank中登陆的IκBα基因(接受号M69043)相应核苷酸序列一致。所制备的AdIκBαM滴度为4.0×1012 pfu/L。AdIκBαM介导IκBαM基因在293细胞中表达,并以剂量依赖性方式显著抑制佛波酯诱导的ECV304细胞NF-κB活化 。结论:AdIκBαM有效介导IκBαM基因表达并特异性抑制NF-κB活性,有望应用于哮喘的基因治疗。 相似文献
975.
Silvano Adami Maurizio Rossini Nicoletta Zamberlan Francesco Bertoldo Romolo Dorizzi Vincenzo Lo Cascio 《Maturitas》1993,17(3):191-196
The transdermal and oral administration of estrogens for one year were compared with respect to the effects on lipid metabolism. Eighty-one postmenopausal women (1.5-3 years after menopause) were randomly divided into three groups. The first two groups received sequential estrogen treatment with either transdermal estradiol (Estraderm TTS, Ciba Geigy; 50 μg/day; 24 women) or 0.625 mg/day conjugated estrogens (Premarin, Wyeth; 20 subjects), respectively. In both groups medroxyprogesterone (10 mg/day per os) was added for 12 days of each cycle. Thirty-five subjects served as control group without therapy. No significant changes in the lipid profile was observed in control subjects after 1 year of follow-up. Serum triglycerides decreased significantly (-10.9 ± 26% S.D.; P < 0.05) in transdermal treated women, whereas it slightly rose in oral estrogen group. Comparable significant decreases in total and low density lipoprotein (LDL) cholesterol (mean range -6.5/-18.0%) were observed in women on estrogen replacement therapy. High density lipoprotein (HDL) cholesterol significantly diminished in transdermal estradiol group, but it rose slightly in the oral estrogen group. Thus the fraction of HDL cholesterol over LDL cholesterol did not change in the transdermal group whereas it significantly rose in subjects treated with oral estrogens. It remains to be established to what extent these differences on lipid metabolism are relevant for the prevention of cardiovascular diseases. 相似文献
976.
Y. Yamamoto Y. Mutoh H. Kobayashi M. Miyashita 《European journal of applied physiology》1987,56(5):522-527
Summary It is uncertain that exercise with reduced frequency breathing (RFB) results in arterial hypoxemia. This study was designed to investigate whether RFB during exercise creates a true hypoxic condition in arterial blood by examining arterial oxygen saturation (SaO2) directly. Six subjects performed ten 30 s periods of exercise on a Monark bicycle ergometer at a work rate of 210 W alternating with 30 s rest intervals. The breath was controlled to use 1 s each for inspiration and expiration, and two trials with different breathing patterns were used; a continuous breathing (CB) trial and an RFB trial consisting of four seconds of breath-holding at functional residual capacity (FRC). Alveolar oxygen pressure during exercise showed a slight but significant (p<0.05) reduction with RFB as compared to CB. However, a marked increase in alveolar-arterial pressure difference for oxygen (A-aDO2) (p<0.05) with RFB over CB resulted in a marked (p<0.05) reduction in arterial oxygen pressure. Consequently, SaO2 fell as low as 88.8% on average. Additional examination of RFB with breath-holding at total lung capacity showed no increases in A-aDO2 in spite of the same amount of hypoventilation as compared with that at FRC. These results indicate that RFB during exercise can result in arterial hypoxemia if RFB is performed with breath-holding at FRC, this mechanism being closely related to the mechanical responses due to lung volume restriction. 相似文献
977.
Waters DL Brooks WM Qualls CR Baumgartner RN 《Mechanisms of ageing and development》2003,124(3):301-309
BACKGROUND: The decline in muscle mass (sarcopenia) with aging may be related to a decline in mitochondrial function. However, investigators have yet to reach a consensus as to whether a decline in mitochondrial function can be attenuated by physical activity has yet to reach a consensus. METHODS: Using dynamic 31PMRS to measure mitochondrial function, we measured baseline Phosphocreatine (PCr), inorganic phosphate (Pi), phosphodiester (PDE), [ADP], pH and recovery times (t(1/2)) for PCr and [ADP] following exercise, in 45 older (73+/-4 years, SD), and 20 younger subjects (25+/-4 years, SD) who were matched for body mass across high and low activity levels and within age and sex groupings. RESULTS: Baseline PCr, and Pi, were lower, and PDE higher in the older subjects compared to younger subjects (all P<0.01). The t(1/2)(ADP) was longer in older subjects (P<0.001) controlling for age and sex in the low activity group (P=0.02). In the older low activity groups, t(1/2)(PCr) was longer than high activity groups. Higher PDE levels were positively correlated with longer t(1/2)(PCr) in the older low activity females (both P<0.05). CONCLUSIONS: Our data suggests that mitochondrial function declines with age in healthy, exercising elderly adults and that the decline appears to be influenced by the level of physical activity. 相似文献
978.
W. P. Vanhelder M. W. Radomski R. C. Goode K. Casey 《European journal of applied physiology》1985,54(4):337-342
Summary Five normal men, aged 20–30 years, participated in three types of exercise (I, II, III) of equal duration (20 min) and total
external work output (120–180 kJ) separated by ten days of rest. Exercises consisted of seven sets of squats with barbells
on the shoulders (I; Maximal Power Output
max=600−900 W), continuous cycling at 50 rev · min−1 (II;
max=100−150 W) and seven bouts of intermittent cycling at 70 rev · min−1 (III;
max=300−450 W).
Plasma cortisol, glucagon and lactate increased significantly (P<0.05) during the exercise and recovery periods of the anaerobic, intermittent exercise (I and III) but not in the continuous,
aerobic exercise (II). No consistent significant changes were found in plasma glucose. Plasma insulin levels decreased only
during exercise II. The highest increase in cortisol and glucagon was not associated with the highest
,
,
max or HR; however it was associated with the anaerobic component of exercise (lactic acid). It is suggested that in exercises
of equal duration and total external work output, the continuous, aerobic exercise (II) led to lowest levels of glucogenic
hormones. 相似文献
979.
Plasma testosterone and catecholamine responses to physical exercise of different intensities in men
D. JeŽová M. Vigaš P. Tatár R. Kvetňanský K. Nazar H. Kaciuba-UŚcilko S. Kozlowski 《European journal of applied physiology》1985,54(1):62-66
Summary Plasma testosterone, noradrenaline, and adrenaline concentrations during three bicycle ergometer tests of the same total work output (2160 J·kg–1) but different intensity and duration were measured in healthy male subjects. Tests A and B consisted of three consecutive exercise bouts, lasting 6 min each, of either increasing (1.5, 2.0, 2.5 W·kg–1) or constant (2.0, 2.0, 2.0 W·kg–1) work loads, respectively. In test C the subjects performed two exercise bouts each lasting 4.5 min, with work loads of 4.0 W·kg–1. All the exercise bouts were separated by 1-min periods of rest.Exercise B of constant low intensity resulted only in a small increase in plasma noradrenaline concentration. Exercise A of graded intensity caused an increase in both catecholamine levels, whereas, during the most intensive exercise C, significant elevations in plasma noradrenaline, adrenaline and testosterone concentrations occurred. A significant positive correlation was obtained between the mean value of plasma testosterone and that of adrenaline as well as noradrenaline during exercise.It is concluded that both plasma testosterone and catecholamine responses to physical effort depend more on work intensity than on work duration or total work output.This work was performed within the Scientific Exchange Programme between the Institute of Experimental Endocrinology, Slovak Academy of Sciences in Bratislava and Medical Research Centre, Polish Academy of Sciences, Warsaw/Project 10.4/ 相似文献
980.
Group treatment for pain and discomfort 总被引:4,自引:0,他引:4
Heinz-Dieter Basler 《Patient education and counseling》1993,20(2-3):167-175
Rheumatic patients very often suffer from chronic pain and impairment and show psychological reactions as a consequence of their physical condition. These reactions may vary from psychophysiological symptoms to anger, anxiety, or depression. We developed a cognitive-behavioral treatment programme in a group setting format with components of relaxation, cognitive restructuring, and the promotion of well-being. Subjects included in the study were given diagnoses of low back pain, tension headache, rheumatoid arthritis, and ankylosing spondylitis. Treatment effects in different diagnostic groups were compared to each other, supporting the assumption that pain reduction is greatest in low back pain and least in ankylosing spondylitis. Subjects with inflammatory rheumatic diseases showed some improvement in self-reported physical complaints and in their feelings of well-being. 相似文献