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At least 325 records · Page 18Linked to original sources
PubMed2000

Kaposi's sarcoma and central nervous system disease: a real association or an artifact of the control group? Terry Beirn Community Programs for Clinical Research on AIDS.

OBJECTIVES: To test the hypothesis that Kaposi's sarcoma (KS) protects against four central nervous system (CNS) diseases in HIV-1-infected individuals. STUDY POPULATION AND DESIGN: The study population of 9404 subjects included participants in Terry Beirn Community Programs for Clinical Research on AIDS (CPCRA) protocols who were enrolled between September 1990 and September 1998. This was an observational study. METHODS: Proportional hazards regression was used to estimate adjusted relative risks for predictors of four central nervous system diseases. Covariates included occurrence of Kaposi's sarcoma, occurrence of other opportunistic infections or malignancies, baseline CD4+ count, and other baseline characteristics. RESULTS: Among the 5944 participants without progression to AIDS at entry, 451 developed a CNS disease. The adjusted relative risk of any CNS disease for those who developed Kaposi's sarcoma versus those who did not develop any AIDS-defining event was 1.41 [95% confidence interval (CI), 0.98-2.03; P = 0.06]. In contrast, the adjusted relative risk of any CNS disease for those with Kaposi's sarcoma versus those with some other non-Kaposi's sarcoma AIDS-defining event was 0.37 (95% CI, 0.24-0.57; P < 0.0001). Among the 3460 participants with progression to AIDS at entry, the adjusted relative risk of any CNS disease for those with Kaposi's sarcoma versus those with some other non-Kaposi's sarcoma AIDS-defining event was 0.71 (95% CI, 0.40-1.25; P = 0.23). CONCLUSIONS: Our analyses indicate that the risk of CNS disease associated with Kaposi's sarcoma depends strongly on the reference or control group chosen. When compared to individuals with other non-Kaposi's sarcoma AIDS-defining diseases, Kaposi's sarcoma is associated with a lower risk of CNS disease in HIV-1 positive individuals. However, when compared to individuals with no AIDS-defining disease or with a similarly mild AIDS-defining disease such as invasive candidiasis, Kaposi's sarcoma is associated with an equivalent risk of CNS disease.

AIDS Dementia Complex↗
PubMed1991

Ischemic preconditioning preserves creatine phosphate and intracellular pH.

BACKGROUND: Ischemic preconditioning slows ATP depletion and ultrastructural damage during the final episode of ischemia. To define the influence of creatine phosphate (CP) and intracellular pH (pHi) on this effect, CP and pHi were serially measured in porcine hearts without collateral circulation by using 31P-NMR spectroscopy and ultrastructural examination. METHODS AND RESULTS: Farm pigs weighing 12-15 kg were anesthetized with Fluothane. The control group underwent a single occlusion (20 minutes or 60 minutes); the preconditioned group underwent four episodes of 5-minute occlusion and 5-minute reperfusion followed by a sustained occlusion (20 minutes or 60 minutes). After ischemic preconditioning, CP increased to 115 +/- 11% (p less than 0.05) of preischemic value and ATP decreased to 84 +/- 8% (p less than 0.05) of preischemic value, but pHi returned to preischemic value. At 5 and 10 minutes of sustained ischemia, CP was significantly preserved in the preconditioned group (control group, 19 +/- 3% versus preconditioned group, 29 +/- 4% at 5 minutes; control group, 5 +/- 3% versus preconditioned group, 11 +/- 3% at 10 minutes; p less than 0.05). At 15 and 20 minutes of sustained ischemia, ATP was significantly preserved in the preconditioned group (control group, 64 +/- 3% versus preconditioned group, 73 +/- 3% at 15 minutes; control group, 51 +/- 7% versus preconditioned group, 62 +/- 2% at 20 minutes; p less than 0.05). At 10, 15, 20, and 25 minutes of sustained ischemia, pHi was significantly higher in the preconditioned group (control group, 6.5 +/- 0.05 versus preconditioned group, 6.7 +/- 0.1 at 10 minutes; control group, 6.3 +/- 0.05 versus preconditioned group, 6.6 +/- 0.06 at 15 minutes; control group, 6.1 +/- 0.1 versus preconditioned group, 6.4 +/- 0.1 at 20 minutes; control group, 6.0 +/- 0.2 versus preconditioned group, 6.3 +/- 0.1 at 25 minutes; p less than 0.05). Ultrastructural changes were milder in the preconditioned group at 20 minutes of sustained ischemia. CONCLUSIONS: In addition to ATP and ultrastructure, preconditioning preserved CP and pHi during sustained ischemia. These protective effects might be due to overshoot phenomenon of CP and/or reduced ATP consumption. The relatively longer period of preservation of pHi, which probably is the result of reduced ATP consumption, indicates its greater contribution to reducing infarct size than that of CP and ATP.

Adenosine Triphosphate↗
PubMed1998

[Comparative study of bone mineralization in children and adolescents with familial short stature and a control group].

OBJECTIVE: Our objective was to study children with familial short stature (FSS) to observe whether they develop bone mineralization similar to that seen in healthy children with an adequate height for their age and sex. PATIENTS AND METHODS: The study included 70 FSS patients (39 boys and 31 girls) between 6 and 20 years of age and 246 control patients with the same mean age and sex of the study group. Bone mineral density was measured in the lumbar spine and forearm by performing dual energy X-ray absorptiometry using a Hologic ADR-1000. RESULTS: The main difference between the FSS population and the control group was in the final adult bone mass, which was 20% less in the lumbar spine and 15% less in the forearm in the FSS group. CONCLUSIONS: A large difference in bone mineralization was observed among the FSS population compared to the control group during infancy and adolescence and this becomes accentuated with age or growth resulting in bone mineralization that is not optimum for facing the losses which occur during adulthood.

Absorptiometry, Photon↗
PubMed2001

[Quality of life of severely injured patients 1 year after trauma. A matched-pair study compared with a healthy control group].

PURPOSE: Severe trauma is accompanied not only with functional disabilities, but also with pain, social and psychological problems of the patient. Those four aspects are important components of the construct quality of life (QoL). The purpose of this study was to evaluate different questionnaires and to compare results between multiply injured patients and healthy controls. METHODS: A group of 43 severely injured patients was matched according to age, gender, educational status and family life situation to 43 persons who had never experienced a severe injury. For the assessment of all four aspects of QoL the patients completed validated questionnaires: Beck-Depression-Inventory (BDI), Short Form Health Survey (SF-36), State-Trait Anxiety Inventory (STAI), a questionnaire for locus of control (KKG), and a questionnaire for social support (SOZU). RESULTS: Patients and the control group showed remarkable differences: 22 of 43 trauma patients suffered from bad health perception (subscale of SF-36) (8/43 control persons), 21 trauma patients reported moderate to severe pain (5/43 control persons), 11 of 43 trauma patients suffered from anxiety (4/43 control persons) and 10 of 43 trauma patients complained about depressive symptoms (2/43 control persons). CONCLUSION: One year after trauma, patients suffer from severe impairments, some even in all four aspects of QoL. The questionnaires used are very well applicable to patients after severe injuries. A trauma-specific Quality of Life Instrument is lacking--and is currently developed by the german trauma registry group.

Adaptation, Psychological↗
PubMed1992

Depth position of spontaneous venous pulsations in ocular hypertensives and control-group discs.

Spontaneous venous pulsation can be observed at the site of entry of retinal veins into the physiological cup of the optic disc. Although it has been speculated that spontaneous vessel pulsation is related to primary open-angle glaucoma, no evaluation has been done on the depth position of such a pulsation inside the cup and its relationship to the intraocular pressure. Using laser scanning tomography, we measured the depth position of the maximal spontaneous vessel pulsation inside the optic cup in 24 discs of 24 patients, including 15 ocular hypertensives and 9 controls. The two groups did not differ significantly in age or refraction. The depth position of the maximal venous collapse, however, showed a significant difference between the two groups (p < 0.005), the mean value being 301 +/- 95 microns beyond the first retinal vessel reflection in the control-group eyes and 507 +/- 193 microns in the ocular hypertensive discs. The location of the depth position of the maximal venous collapse within the excavation could be a parameter that indicates the individual pressure tolerance of the ocular tissues.

Adult↗
PubMed1982

Is UVB treatment of psoriasis safe? A study of extensively UVB-treated psoriasis patients compared with a matched control group.

The aim of the study was to investigate whether or not extensively UVB-treated psoriatics ran a greater risk of developing skin cancer than did controls. The 85 most extensively UVB-treated psoriasis patients during recent decades have been investigated with regard to premalignant and malignant skin lesions and compared with a population matched for age, sex, and geographic region. The prevalence of persons who had or had had premalignant/malignant skin lesions was 5.9% (n = 85) in the psoriasis group, vs. 10.1% in the control group (n = 338). This difference is not statistically significant and the confidence limits are such that it is unlikely that the psoriasis patients treated in the past have an increased prevalence of premalignant and malignant skin lesions. A multiple regression analysis has been conducted among the controls, showing a correlation between premalignant/malignant skin changes and advanced age and outdoor occupations. No such correlation was found for the factors: sex, skin type, or travel to southern latitudes.

Adult↗