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Background

Patients with chronic heart failure have vulnerable myocardial function and are susceptible to electrolyte disturbances. In these patients, diuretic treatment is frequently prescribed, though it is known to cause electrolyte disturbances. Therefore, we investigated the association between altered calcium homeostasis and the risk of all-cause mortality in chronic heart failure patients.

Methods

From Danish national registries, we identified patients with chronic heart failure with a serum calcium measurement within a minimum 90 days after initiated treatment with both loop diuretics and angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers. Patients were divided into 3 groups according to serum calcium levels, and Cox regression was used to assess the mortality risk of <1.18 mmol/L (hypocalcemia) and >1.32 mmol/L (hypercalcemia) compared with 1.18 mmol/L–1.32 mmol/L (normocalcemia) as reference. Hazard ratios (HRs) with 95% confidence intervals (CIs) were calculated.

Results

Of 2729 patients meeting the inclusion criteria, 32.6% had hypocalcemia, 63.1% normocalcemia, and 4.3% hypercalcemia. The highest mortality risk was present in early deaths (≤30 days), with a HR of 2.22 (95% CI; 1.74-2.82) in hypocalcemic patients and 1.67 (95% CI; 0.96-2.90) in hypercalcemic patients compared with normocalcemic patients. As for late deaths (>30 days), a HR of 1.52 (95% CI; 1.12-2.05) was found for hypocalcemic patients and a HR of 1.87 (95% CI; 1.03-3.41) for hypercalcemic patients compared with normocalcemic patients. In adjusted analyses, hypocalcemia and hypercalcemia remained associated with an increased mortality risk in both the short term (≤30 days) and longer term (>30 days).

Conclusion

Altered calcium homeostasis was associated with an increased short-term mortality risk. Almost one-third of all the heart failure patients suffered from hypocalcemia, having a poor prognosis.  相似文献   
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Summary Experimental diabetes can be produced by agents with specific toxicity for pancreatic islet B cells. This effect has been reported to be modified both in vitro and in vivo by various radical scavengers including the enzyme Superoxide dismutase. Copper(II)(3,5-diisopropylsalicylate)2 is lipophilic and possesses Superoxide dismutase bioactivity. Prior administration of this compound to male rats appeared to attenuate the severity of streptozotocin-induced diabetes as assessed by glycosuria and glucose tolerance. Diisopropylsalicylate, which has no Superoxide dismutase activity, did not alter the severity of streptozotocin-induced diabetes. Rats treated with the copper complex, with Streptozotocin or with a combination of the two agents gained 50% less weight than untreated controls, or rats treated with diisopropylsalicylate. The attenuation of diabetes by the copper-complex may represent partial protection of the B cells against Streptozotocin damage, although an extrapancreatic, toxic effect cannot be ruled out.  相似文献   
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Spinal primary dural lymphoma (PDL) is uncommon with a total of 37 previous well‐documented cases reported, including one diagnosed in the authors' institution. More recently we encountered an additional case of spinal PDL that, similarly to our previous case, was grade 1–2 follicular B‐cell PDL. Our two cases were diagnosed over a 3‐year interval in a 72‐year‐old female and a 74‐year‐old male, respectively. An exhaustive literature review on PDL was performed consequently to reveal that: (i) spinal and cerebral sites of involvement by PDL are constantly mutually exclusive; and (ii) unlike cerebral PDL, which is usually of marginal zone B‐cell type, only two of the 38 cases of spinal PDL were diagnosed as such, diffuse large B‐cell lymphoma being the most commonly encountered type in the spine. This divergence infers that, in contrast to the prevailing concept that PDL is a unique disease group, PDL appears to be rather heterogeneous with a difference in predilection of lymphoma type for the anatomical site of dural involvement. Such a site‐specific lymphoma‐type predilection phenomenon, well‐recognized in other organ systems, has not been acknowledged in PDL. This report brings new insights into PDL, and may contribute to a better understanding of nervous system pathophysiology and lymphoma classification.  相似文献   
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Empirical research on informed consent has shown that study participants often do not fully understand consent information. This study assessed participant understanding of three mock consent approaches describing an HIV-prevention clinical trial in Lilongwe, Malawi prior to trial implementation. Pregnant women (n?=?297) were systematically selected from antenatal-care waiting lines and sequentially allocated to receive an enhanced standard consent form (group 1), a context-specific consent form (group 2), or context-specific counseling cards (group 3). Understanding of research concepts and study procedures was assessed immediately postintervention and at 1-week follow-up. At postintervention, participants in groups 2 and 3 understood more about research concepts and study procedures compared with group 1. Group 3 participants also understood more about study procedures compared with group 2. At follow-up, participants in groups 2 and 3 continued to understand more about research concepts and study procedures. Context-specific approaches improved understanding of consent information in this study.  相似文献   
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Background

High trait anxiety (HTA) causes an impaired quality of life (QOL) and fatigue in women with breast cancer (BC) and benign breast disease (BBD). We examined whether the lowered QOL was determined solely by the personality characteristic HTA or by the combination of personality and diagnosis.

Methods

In a prospective longitudinal study, women with BC (n = 152), BBD (n = 205), or gallstone disease (GD) before laparoscopic cholecystectomy (n = 128) were included. Questionnaires concerning trait anxiety (baseline), fatigue, and QOL were completed at baseline and at 6 months. Multivariate linear regression analysis was performed to analyze the predictors for QOL at 6 months.

Results

At 6 months QOL scores were increased in the GD group, especially in women without HTA. For women without HTA, in the BBD group the scores for fatigue and physical QOL had improved at 6 months, whereas in the BC group physical QOL and fatigue was impaired. Women with HTA scored unfavorably on fatigue and QOL. HTA was the most important factor influencing QOL.

Conclusions

The course of QOL and fatigue during follow-up were significantly different for each diagnosis. Particularly HTA had a negative impact on QOL and fatigue. Especially the combination HTA and BC caused impaired QOL and fatigue. We recommend identifying women with BC and HTA and offer them a tailor-made follow-up protocol.  相似文献   
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