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121.
Suspicions that mild zinc deficiency is common among the elderly cannot be confirmed or refuted because definitive indicators of zinc status are lacking. The goal of this study was to document the clinical responsiveness of parameters of zinc status in a group of older adults consuming a carefully controlled diet: first moderately low in zinc (3.97 mg/day for 15 days) and then high in zinc (28.19 mg/day for 6 days).

Fifteen older adults (mean age = 66.6 yrs) volunteered to consume a marginally zinc-deficient diet for 15 days followed by 6 days of zinc repletion. Plasma concentrations of erythrocyte metallothionein and the enzyme 5′-nucleotidase, as well as levels of zinc, alkaline phosphatase, copper and ceruloplasmin were measured before and after zinc depletion and repletion.

Plasma zinc levels were not altered during the study. Alkaline phosphatase (AP) values did not change in the expected direction, although a small decrease in AP following zinc repletion was statistically significant. Erythrocyte metallothionein results followed a pattern similar to that of alkaline phosphatase, little change, but a small, statistically significant drop after zinc repletion. As expected, there were no diet-associated changes in plasma copper and ceruloplasmin levels. In contrast, plasma concentrations of the enzyme 5′-nucleotidase decreased (p < 0.01) from 2.7 +/? 0.5 to 1.1 +/? 0.5 U during zinc depletion and increased (p < 0.05) to 2.2 +/? 0.4 U after 6 days of repletion.

Mild zinc deficiency is difficult to detect. In this study, traditional indicators such as plasma zinc and alkaline phosphatase did not change as would be expected in response to alterations in zinc intake. Likewise, erythrocyte metallothionein did not respond to altered zinc intakes as expected but this factor may reflect long-standing or more severe zinc depletion and thus requires additional study. Activity of the enzyme 5′-nucleotidase appears responsive to acute changes in zinc intake; however, more work is needed to define how well these activities will reflect zinc intake in other types of subjects.  相似文献   
122.

Background  

Interventions other than medications in the management of osteoporosis are often overlooked. The purpose of this study was to investigate the association of physical activity and calcium intake with bone parameters.  相似文献   
123.
BACKGROUND: Beck Hopelessness Scale (BHS) has been translated and validated in many languages. AiM: The validation of the English version of BHS in advanced cancer patients receiving palliative treatment in Greece. METHODS: The final sample was 112 advanced cancer patients. Internal consistency, item-total correlations, and test-retest using four different approaches were calculated for the assessment of the reliability. Construct validity was used by examining correlations between BHS, Hospital Anxiety and Depression Scale (HAD-Depression) and the Schedule of Attitudes toward Hastened Death (SAHD). Known-groups validity was also assessed by detecting group differences according to disease severity as measured by the Eastern Cooperative Oncology Group (ECOG) performance status. Univariate and multivariate analyses were constructed to explore the relationship between hopelessness, depression, hastened death and the patients' demographic and clinical characteristics. RESULTS: One factor solution was yielded accounted for 46.64% of the variance. The test-retest reliability was satisfactory (p < 0.0005). Validity as performed using known-group analysis showed good results. Most significant correlations were found between BHS, ECOG (p = 0.018) and gender (p = 0.08). The strongest predictors were gender (p = 0.050) and ECOG (p = 0.045). CONCLUSIONS: BHS seemed to be a useful instrument to assess pessimistic attitude and hopelessness in a Greek cancer population, with valid psychometric properties.  相似文献   
124.
125.
Summary Mice infected with bacteria develop an interferon- (IFN-) dependent hypersensitivity to lipopolysaccharide (LPS) and other bacterial components. The broader aim of this study is to find out whether such hypersensitivity also occurs in patients suffering from bacterial infections. The capacity of stimulated peripheral blood cells from infected, intensive-care patients to produce cytokines (IFN-, tumor necrosis factor-alpha (TNF-) and interleukin-6 (IL-6)) was compared to that of healthy donors. Culturing of the cells was carried out preferentially in whole blood diluted 1:3. Whole blood cultures (WBC) were stimulated with lipopolysaccharide (LPS), whole killedSalmonella typhimurium andStaphylococcus aureus and concanavalin A (ConA), and the cytokine production was determined. Two main findings emerged from this study: The IFN- production by WBC of patients was, compared to healthy donors, markedly suppressed, regardless of stimulus used. Further, patients' WBC exhibited a suppressed TNF- production after stimulation with LPS. Surprisingly, following stimulation with bacteria (S. typhimurium andS. aureus) an elevated TNF- and IL-6 response was obtained. Thus, in severely infected patients the cytokine responses of peripheral blood cells to LPS may be suppressed, while the response to other bacterial components is enhanced.  相似文献   
126.
The innate immune response to Gram-negative bacteria depends mainly on the ability of the host to respond to the LPS component. Consequently, the state of LPS sensitivity at the time of infection and the numbers of invading bacteria (i.e. the amounts of LPS) are primary factors determining the innate responses provoked by Gram-negative pathogens. LPS sensitivity increases following treatment of mice with live or killed micro-organisms. Two types of sensitization have been recognized, strong, IFN-gamma-dependent and moderate IFN-gamma-independent. IL-12 and IL-18 are intimately involved in the induction of IFN-gamma by bacteria. We showed that Gram-negative bacteria induce IFN-gamma in mice also by an IFN-beta-dependent pathway that requires IL-18 and is independent of IL-12 signaling. This pathway is STAT4 dependent, the activation of which is directly linked to IFN-beta. Further, IFN-beta can be replaced by IFN-alpha. While different components of Gram-negative bacteria induce IL-12 and IL-18, LPS seems to be the only component in these bacteria capable of inducing IFN-beta. Therefore, the IFN-beta pathway of IFN-gamma induction, unlike the IL-12 pathway, proceeds only in LPS responder mice. The IFN-alpha/beta-dependent pathway is expected to play a role whenever IFN-alpha or IFN-beta, and IL-18 are produced concomitantly during infection.  相似文献   
127.
BACKGROUND: Older age is associated with less aggressive treatment and higher short-term mortality due to serious illness. It is not known whether less aggressive care contributes to this survival disadvantage in elderly persons. OBJECTIVE: To determine the effect of age on short-term survival, independent of baseline patient characteristics and aggressiveness of care. DESIGN: Secondary analysis of data from a prospective cohort study. SETTING: Five academic medical centers participating in SUPPORT (Study to Understand Prognoses and Preferences for Outcomes and Risks of Treatments). PATIENTS: 9105 adults hospitalized with one of nine serious illnesses associated with an average 6-month mortality rate of 50%. MEASUREMENTS: Survival through 180 days of follow-up. In Cox proportional hazards modeling, adjustment was made for patient sex; ethnicity; income; baseline physical function; severity of illness; intensity of hospital resource use; presence of do-not-resuscitate orders on study day 1; and presence and timing of decisions to withhold transfer to the intensive care unit, major surgery, dialysis, blood transfusion, vasopressors, and tube feeding. RESULTS: The mean (+/- SD) patient age was 63 +/- 16 years, 44% of patients were female, and 16% were black. Overall survival to 6 months was 53%. In analyses that adjusted for sex, ethnicity, income, baseline functional status, severity of illness, and aggressiveness of care, each additional year of age increased the hazard of death by 1.0% (hazard ratio, 1.010 [95% CI, 1.007 to 1.013]) for patients 18 to 70 years of age and by 2.0% (hazard ratio, 1.020 [CI, 1.013 to 1.026]) for patients older than 70 years of age. Adjusted estimates of age-specific 6-month mortality rates were 44% for 55-year-old patients, 48% for 65-year-old patients, 53% for 75-year-old patients, and 60% for 85-year-old patients. Similar results were obtained in analyses that did not adjust for aggressiveness of care. Acute physiology and diagnosis had much larger relative contributions to prognosis than age. CONCLUSIONS: We found a modest independent association between patient age and short-term survival of serious illness. This age effect was not explained by the current practice of providing less aggressive care to elderly patients.  相似文献   
128.
The purpose of this study was to translate, adapt, and validate a Greek version of the Disabilities of the Arm, Shoulder, and Hand (DASH) Questionnaire. The English version of DASH was translated into Greek (DASH-GR) and cultural adaptation was performed. Subsequently, psychometric properties and validity were assessed in 106 consecutive eligible patients presenting with a variety of unilateral upper limb disorders. All patients completed the Short Form 36 Health Survey questionnaire and the DASH-GR. Test-retest reliability was assessed in a subgroup of 35 patients who filled in the questionnaire seven days later. The internal consistency of the 30 items of the DASH-GR, estimated by the internal consistency coefficient (Cronbach's alpha) was 0.96. The difference between the individual scores of the initial assessment and reassessment of the DASH ranged from -6.5 to 14.5 (mean difference was 3.74 (SD+/-6.1)). The correlation coefficient between total scores of the initial assessment and reassessment was high (Pearson's r=0.918, p<0.0005) (Kentall tau-b=0.72, p<0.001). The correlation coefficient between the DASH-GR and SF-36 total scores was 0.625 (p<0.001), showing a strong correlation between the two questionnaires. The Greek version of the DASH retains the characteristics of the English original and is a reliable and valid instrument that can provide a standardized measure of patient-centered outcomes in Greek-speaking patients with unilateral disorders of the upper limb.  相似文献   
129.
The growing interest in the psychological distress and the multidimensionality of pain in patients with cancer has been the major reason for the conduction of this study. The aims were to evaluate psychological distress and pain in patients with advanced cancer and the impact of pain severity and pain interference dimensions on the anxiety and depression. One hundred twenty patients with advanced cancer were surveyed at a palliative care unit in Athens, Greece. Greek versions of the Hospital Anxiety and Depression (G-HAD) scale and the Brief Pain Inventory were administered. Information concerning patients' treatment received was acquired from the medical records, whereas physicians recorded their clinical condition. The analysis showed that significant associations were found between pain interference to "mood" and HAD-A (anxiety) (r = 0.252, P = .005) and between pain interference to "relations with other people" and HAD-A (r = 0.474, P < .0005). Multiple regression analyses showed that "average pain" (P < .05), pain interference to "walking ability" (P < .05), "normal work" (P < .05, and "relations with other people" are significant predictors of HAD-anxiety (HAD-A) (P < .0005), explaining 46.2% of total variance. For depression (HAD-D), the Greek version of the Brief Pain Inventory dimension that serve as predictor is "enjoyment of life," as well as the demographic variables of "age," and "gender" (P < .05), explaining 22.2% of variance. Moreover, a further analysis of the pain severity and pain interference scales showed that they differentiate the anxiety of the patients with cancer. In this patient sample, pain interference and, to a lesser extent, pain severity was significantly associated with psychological distress (anxiety and pain), whereas pain interference to "walking ability," "normal work," and "relations with other people" was found to be more prominent and troublesome to patients' anxiety than that to patients' depression.  相似文献   
130.
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