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1.

Background

While the "widowhood effect" is well known, there is substantial heterogeneity in the magnitude of effects reported in different studies. We conducted a meta-analysis of widowhood and mortality, focusing on longitudinal studies with follow-up from the time of bereavement.

Methods and Findings

A random-effects meta-analysis was conducted to calculate the overall relative risk (RR) for subsequent mortality among 2,263,888 subjects from 15 prospective cohort studies. We found a statistically significant positive association between widowhood and mortality, but the widowhood effect was stronger in the period earlier than six months since bereavement (overall RR = 1.41, 95% CI: 1.26, 1.57) compared to the effect after six months (overall RR = 1.14, 95% CI: 1.10, 1.18). Meta-regression showed that the widowhood effect was not different for those aged younger than 65 years compared to those older than 65 (P = 0.25). There was, however, a difference in the magnitude of the widowhood effect by gender; for women the RR was not statistically significantly different from the null (overall RR = 1.04, 95% CI: 1.00, 1.08), while it was for men (overall RR = 1.23, 95% CI: 1.18, 1.28).

Conclusions

The results suggest that further studies should focus more on the mechanisms that generate this association especially among men.  相似文献   

2.

Background

Type 2 diabetes mellitus (DM) is a frequent co-morbidity among patients undergoing coronary artery bypass grafting (CABG) surgery. The aim of this study was to evaluate the impact of DM on the early- and long-term outcomes of patients who underwent isolated CABG.

Methods

We performed an observational cohort study in a large tertiary medical center over a period of 11 years. All data from patients who had undergone isolated CABG surgery between 2004 and 2014 were obtained from our departmental database. The study population included 2766 patients who were divided into two groups: Group I (1553 non-diabetic patients), and Group II (1213 patients suffering from type 2 DM). Group II patients were then divided into two subgroups: subgroup IIA (981 patients treated with oral antihyperglycemic medications) and subgroup IIB (232 insulin-treated patients with or without additional oral antihyperglycemic drugs). In-hospital, 1-, 3-, 5- and 10-year mortality outcome variables were evaluated. Mean follow-up was 97?±?41 months.

Results

In-hospital mortality was similar between Group I and Group II patients (1.87% vs. 2.31%, p?=?0.422) and between the subgroups IIA and IIB (2.14% vs. 3.02%, p?=?0.464). Long-term mortality (1, 3, 5 and 10 years) was higher in Group II (DM type 2) compared with Group I (non-diabetic patients) (5.3% vs. 3.6%, p?=?0.038; 9.3% vs. 5.6%, p?<?0.001; 15.3% vs. 9.3%, p?<?0.001 and 47.3% vs. 29.6% p?<?0.001). Kaplan–Meier analysis demonstrated that all-cause mortality was higher in Group II compared with Group I (p?<?0.001) and in subgroup IIB compared with subgroup IIA (p?=?0.001). Multivariable analysis showed that DM increased the mortality hazard by twofold, and among diabetic patients, insulin treatment increased the mortality hazard by twofold.

Conclusions

Diabetic and non-diabetic patients have similar in-hospital mortality rates. Survival rates of diabetic patients start to deteriorate 3 year after surgery. Type 2 DM is an independent predictor for long-term mortality after isolated CABG surgery. Mortality is even higher when the diabetes treatment strategy included insulin.
  相似文献   

3.
1. The effect of short- (2 wk) and long-term (20 wk) streptozotocin diabetes was studied on urine, blood, liver, heart, brain, skeletal muscle, pancreas and kidney concentrations of acid-soluble carnitine and free myo-inositol. 2. Short-term diabetic rats excreted significantly higher concentrations of carnitine as well as myoinositol than normal rats. Blood carnitine and myo-inositol were not different between normal and diabetic rats. Diabetes caused a decrease in liver, brain and pancreatic carnitine, but not in heart, skeletal muscle and kidney. Myo-inositol concentration was decreased in liver, heart and kidney but not in brain, pancreas and skeletal muscle. 3. Long-term diabetic rats had higher urinary excretions of both carnitine and myo-inositol. Blood carnitine did not change; however, myo-inositol was higher in diabetic than in normal rats. Diabetes caused a significant increase in liver and a decrease in heart, brain, skeletal muscle and pancreatic content of carnitine; no difference in kidney carnitine was noted. Myo-inositol content was elevated only in liver of diabetic rats. 4. We suggest that carnitine and myo-inositol concentrations are influenced both by short- and long-term diabetes through changes in tissue metabolism.  相似文献   

4.
目的:探讨孕妇超重或肥胖与死产的关系。方法:采用RevMan4.2.10版本软件中的Meta分析,检索Pubmed文献数据库中1980年~2008年有关死产的孕妇超重或肥胖因素文献,并进行定量综合分析。结果:经检索、筛选后纳入的有关死产的孕妇超重或肥胖因素文献11篇;经异质性检验,采用固定效应模型、随机效应模型进行定量综合分析。综合结果表明孕妇超重、孕妇肥胖对死产的影响OR值分别为1.21(95%CI:1.05-1.40)、1.69(95%CI:1.51-1.90)。结论:孕妇因超重或肥胖的死产率明显高于正常体重孕妇。  相似文献   

5.
Although hypocalcemia has been observed during stress, the cause(s) is still unknown. The effect of short- and long-term restraint stress on calcitonin (CT) secretion and on plasma calcium (Ca), inorganic phosphate (P), total protein (TP), and corticosterone (CORT) were investigated in the male and female Sprague-Dawley rat. The rats were restrained in the supine position for two hours/day for either one day (STS) or for 14 days (LTS), and compared to normal controls (CON). Plasma Ca levels in both STS and LTS rats were significantly lower and mean plasma CORT levels in female stressed rats were significantly higher than those in sex-matched CON rats. However, mean basal levels of plasma CT did not differ among these three groups for either sex. Similarly, mean increment of plasma CT after Ca infusion (Ca 10 mg/100 g, i.v.) did not differ between STS or LTS rats and CON rats. These data reveal no causal relationship between CT and the hypocalcemia during either short-or long-term stressful stimuli.  相似文献   

6.
Increase in heart metabolism during severe exercise facilitates production of ROS and result in oxidative stress. Due to shortage of information, the effect of chronic strength exercise on oxidative stress and contractile function of the heart was assessed to explore the threshold for oxidative stress in this kind of exercise training. Male Wistar rats (80) were divided into two test groups exercised 1 and 3 months and two control groups without exercise. Strength exercise was carried by wearing a Canvas Jacket with weights and forced rats to lift the weights. Rats were exercised at 70% of maximum lifted weight 6 days/week, four times/day, and 12 repetitions each time. Finally, the hearts of ten rats/group were homogenized and MDA, SOD, GPX, and catalase (CAT) were determined by ELISA method. In other ten rats/group, left ventricle systolic and end diastolic pressures (LVSP and LVEDP) and contractility indices (LVDP and +dp/dt max) and relaxation velocity (−dp/dt max) were recorded. The coronary outflow was collected. Short- and long-term strength exercise increased heart weight and heart/BW ratio (P < 0.05). In the 3-month exercise group, basal heart rate decreased (P < 0.05). LVEDP did not change but LVDP, +dp/dt max, −dp/dt max, and coronary flow significantly increased in both exercise groups (P < 0.05). None of MDA or SOD, GPX, and CAT significantly changed. The results showed that sub-maximal chronic strength exercise improves heart efficiency without increase in oxidative stress index or decrease in antioxidant defense capacity. These imply that long-time strength exercise up to this intensity is safe for cardiac health.  相似文献   

7.
Excess salt loads in most non-mammalian vertebrates are dealt with by a variety of extra-renal salt-secreting structures collectively described as salt glands. The best studied of these are the supra-orbital nasal salt glands of birds. Two distinct types of response to osmoregulatory disturbances are shown by this structure: a progressive adaptive response on initial exposure to a salt load that results in the induction and enhancement of the secretory performance or capabilities of the gland; and the rapid activation of existing osmoregulatory mechanisms in the adapted gland in response to immediate osmoregulatory imbalance. Not only is the time-frame of these two types of response very different, but the responses usually involve fundamentally different processes: e.g., the growth and differentiation of osmoregulatory structures and their components in the former case, compared with the rapid activation of ion channels, pumps etc. in the latter. Despite marked differences in the nature and time-frame of these responses, they both are apparently triggered by neuronally released acetylcholine, which acts at muscarinic receptors on the secretory cells to induce an inositol phosphate-dependent increase in cytosolic-free calcium concentrations ([Ca2+]i). Therefore, the question arises as to how the cells produce the appropriate distinct response using a single common signal (i.e., an increase in [Ca2+]i). Examination of the features of this signaling pathway in the two conditions described, reveals that they each are uniquely tuned to generate a response with the characteristics appropriate for the cells' requirements. This tuning of the signal involves often rather subtle changes in the overall signaling pathway that are part of the adaptive differentiation process.  相似文献   

8.
9.
10.
11.
1. It has been discussed for over 100 years whether short-term memory (STM) is separate from, or just an early phase of, long-term memory (LTM). The only way to solve this dilemma is to find out at least one treatment that blocks STM while keeping LTM intact for the same task in the same animal.2. The effect of a large number of treatments infused into the hippocampus, amygdala, and entorhinal, posterior parietal or prefrontal cortex on STM and LTM of a one-trial step-down inhibitory avoidance task was studied. The animals were tested at 1.5 h for STM, and again at 24 h for LTM. The treatments were given after training.3. Eleven different treatments blocked STM without affecting LTM. Eighteen treatments affected the two memory types differentially, either blocking or enhancing LTM alone. Thus, STM is separate from, and parallel to the first hours of processing of, LTM of that task.4. The mechanisms of STM are different from those of LTM. The former do not include gene expression or protein synthesis; the latter include a double peak of cAMP-dependent protein kinase activity, accompanied by the phosphorylation of CREB, and both gene expression and protein synthesis.5. Possible cellular and molecular events that do not require mRNA or protein synthesis should account for STM. These might include a hyperactivation of glutamate AMPA receptors, ribosome changes, or the exocytosis of glycoproteins that participate in cell addition.  相似文献   

12.
Recent research findings have highlighted the importance of early life conditions as risk factors for adult diseases and therefore determinants of subsequent survival. Given that individuals born during different seasons in seasonal environments experience different early-developmental conditions, an analysis of the effects of the season of birth on survival is considered an effective approach in clarifying the influence of early life conditions on survival in later life. In the present study, we analyzed the long-term effects of early developmental conditions in a historical population in which both nutritional levels and the burden of infectious diseases showed a seasonal variation. Using a semi-computerized linkage process, we were able to match birth and death data for 4,646 individuals born between 1634 and 1870 in the village of Es Mercadal (Minorca Island, Spain). To determine ecological differences associated with the season of birth, we first evaluated the association between season of birth and early life survival. This analysis helped us to determine seasonal variations in early life conditions such as infectious burden and nutritional levels. The season of birth had a significant effect on long-term survival in the birth cohort 1800-1870: summer births had a lower risk of death after age 15. We explain these results in terms of lower susceptibility to degenerative diseases in adult years due to superior in utero nutrition for summer births. These findings support the fetal origin hypothesis which states that the early life environment plays a key role in shaping the subsequent phenotype and risk of adult disease.  相似文献   

13.

Background

Guidelines exist for the surgical treatment of hip fracture, but the effect of early surgery on mortality and other outcomes that are important for patients remains unclear. We conducted a systematic review and meta-analysis to determine the effect of early surgery on the risk of death and common postoperative complications among elderly patients with hip fracture.

Methods

We searched electronic databases (including MEDLINE and EMBASE), the archives of meetings of orthopedic associations and the bibliographies of relevant articles and questioned experts to identify prospective studies, published in any language, that evaluated the effects of early surgery in patients undergoing procedures for hip fracture. Two reviewers independently assessed methodologic quality and extracted relevant data. We pooled data by means of the DerSimonian and Laird random-effects model, which is based on the inverse variance method.

Results

We identified 1939 citations, of which 16 observational studies met our inclusion criteria. These studies had a total of 13 478 patients for whom mortality data were complete (1764 total deaths). Based on the five studies that reported adjusted risk of death (4208 patients, 721 deaths), irrespective of the cut-off for delay (24, 48 or 72 hours), earlier surgery (i.e., within the cut-off time) was associated with a significant reduction in mortality (relative risk [RR] 0.81, 95% confidence interval [CI] 0.68–0.96, p = 0.01). Unadjusted data indicated that earlier surgery also reduced in-hospital pneumonia (RR 0.59, 95% CI 0.37–0.93, p = 0.02) and pressure sores (RR 0.48, 95% CI 0.34–0.69, p < 0.001).

Interpretation

Earlier surgery was associated with a lower risk of death and lower rates of postoperative pneumonia and pressure sores among elderly patients with hip fracture. These results suggest that reducing delays may reduce mortality and complications.Among elderly patients, hip fracture is associated with a one-year mortality rate ranging from 14% to 36%1 and also with profound temporary and sometimes permanent impairment of independence and quality of life.2 As the elderly population increases, the annual number of hip fractures globally is expected to exceed 7 million over the next 40 to 50 years.3Current guidelines4 indicate that surgery for hip fracture should be performed within 24 hours of injury, as earlier surgery has been associated with better functional outcome, shorter hospital stay, shorter duration of pain and lower rates of nonunion, postoperative complications and mortality.511Proponents of early treatment argue that this approach minimizes the length of time a patient is confined to bed rest, thereby reducing the risk of associated complications, such as pressure sores, deep vein thrombosis and urinary tract infections.8 However, those favouring a delay believe it provides the opportunity to optimize patients’ medical status, thereby decreasing the risk of perioperative complications.8 A further challenge to resolving the debate is the lack of an accepted definition of early surgery.12 Uncertainty exists about whether 24, 48 or 72 hours, or a longer period, should be considered to represent an “unacceptable delay” for hip fracture surgery.We undertook a systematic review and meta-analysis to inform this debate. More specifically, we addressed the following question: Among patients 60 years of age or older who underwent surgery for hip fracture, what was the effect of early surgery, relative to delayed surgery, on all-cause mortality and postoperative complications?  相似文献   

14.

Background

Diagnostic and treatment approaches for sarcoidosis have changed dramatically over the past decade. Yet, the most recent reports of trends in hospitalizations of sarcoidosis patients are over ten years old. The objectives of this study were to determine the incidence of sarcoidosis among hospitalized patients and to analyze recent trends and seasonality of hospitalizations in sarcoidosis patients.

Methods

We performed a retrospective cohort study of the Nationwide Inpatient Sample from 1998 through 2008. We identified all hospitalizations with a primary or secondary diagnosis of sarcoidosis (ICD-9-CM code 135). Incidence was modeled as a seasonal time series about a linear trend.

Results

Time series analysis of the monthly number of hospitalizations revealed a distinct positive linear trend. Over the study period, the number of hospitalized patients with sarcoidosis increased from 37,516 to 70,947 cases. Trends were most pronounced in patients older than 55?years (p?<?0.0001), African Americans (p?<?0.0001), females (p?=?0.0289), and non-Medicaid populations (p?<?0.0001). Hospitalizations are seasonal with highest incidence in January through March.

Conclusions

Hospitalizations among sarcoidosis patients have almost doubled during the past decade, with disproportionate rate increases in African Americans, women, and older patients. The rate also increases among patients with insurance other than Medicaid. This study indicates the need for heightened surveillance of sarcoidosis patients given the unknown consequences of evolving treatment approaches. Our results point to a need for research investigating risk factors for hospitalization, including medications, co-morbidities, demographics, and socioeconomic status.  相似文献   

15.
ABSTRACT: BACKGROUND: Despite the benefits of beta-blockers in patients with established or sub-clinical coronary artery disease, their use in patients with chronic obstructive pulmonary disease (COPD) has been controversial. Currently, no systematic review has examined the impact of beta-blockers on mortality in COPD. METHODS: We systematically searched electronic bibliographic databases including MEDLINE, EMBASE and Cochrane Library for clinical studies that examine the association between beta-blocker use and all cause mortality in patients with COPD. Risk ratios across studies were pooled using random effects models to estimate a pooled relative risk across studies. Publication bias was assessed using a funnel plot. RESULTS: Our search identified nine retrospective cohort studies that met the study inclusion criteria. The pooled relative risk of COPD related mortality secondary to beta-blocker use was 0.69 (95% CI: 0.62-0.78; I2=82%). CONCLUSION: The results of this review are consistent with a protective effect of beta-blockers with respect to all cause mortality. Due to the observational nature of the included studies, the possibility of confounding that may have affected these results cannot be excluded. The hypothesis that beta blocker therapy might be of benefit in COPD needs to be evaluated in randomised controlled trials.  相似文献   

16.
Compensatory or catch-up growth (CG) is widely observed following periods of resource deprivation. Because of this commonness, it is generally assumed that compensatory growth is adaptive, but most theory to date has explicitly ignored considerations of fitness. Following a period of deprivation, when resources become plentiful again, individuals may not respond at all and continue on a "normal" trajectory from a smaller size at age, may exhibit faster-than-normal growth immediately following the end of the period, or may adopt a growth strategy that involves faster-than-normal growth at some later time. Compensating individuals may also overtake control individuals who have been growing normally throughout. We hypothesize that the key to understanding CG is that growth leads to the accumulation of damage at the cellular level that is expressed (and thus must be modeled) at the level of the organism. We show that a life-history model incorporating the mortality consequences of both size and damage provides a framework for understanding compensatory growth. We use the theory to classify physiological and life-history characteristics for which CG is predicted to be the optimal response to deprivation.  相似文献   

17.
The primary purpose of this study was to determine whether current and midlife obesity status provide independent information on mortality risk in elderly persons. Analyses were based on 3,238 participants from the original Framingham Heart Study (FHS) cohort who lived to at least 70 years of age and who had BMI measures from when they were in their 50s. Within this group of 70-year olds, obesity based on current BMI was associated with a 21% increased risk of mortality (P = 0.019) whereas obesity in 70-year olds based on BMI measures obtained at around 50 years of age was associated with a 55% increased risk of mortality (P < 0.0001). Compared to 70-year olds who were nonobese at both 50 and 70 years of age, mortality risk was increased by 47% (P < 0.001) in those who were obese at both 50 and 70 years of age, increased by 56% (P < 0.001) in those who were obese at 50 years of age and nonobese at 70 years of age, and not significantly different (P > 0.9) in those who were nonobese at 50 years of age and obese at 70 years of age. In summary, in this cohort of elderly adults, midlife and current BMI had independent effects on mortality risk. Specifically, although mortality risk was increased in obese older adults who were already obese at midlife, this was not the case for newly obese older adults. Conversely, nonobese older adults who were obese at midlife had an increased mortality risk. These observations imply that it is imperative to consider an elderly adult's BMI in context of their BMI at midlife.  相似文献   

18.
Adult male rats (3 months old) were tested for their copulatory behavior: those satisfying the criterion of sexual vigor in the last three out of five weekly tests were randomly divided into two groups and adrenalectomized or sham operated, and their copulatory activity was retested 35 and 420 days after surgery. Short-term adrenalectomy did not modify any of the parameters of sexual behavior. On the other hand, a higher percentage of adrenalectomized than of sham-operated rats still had successful sexual performance when 18 months old (420 days after surgery); moreover, blood levels of testosterone were higher in adrenalectomized than in sham-operated old rats. The possibility that adrenal steroids may play a role in the age-linked decline in male sexual activity in mammals is discussed.  相似文献   

19.
In the cortex, synaptic latencies display small variations ( approximately 1-2 ms) that are generally considered to be negligible. We show here that the synaptic latency at monosynaptically connected pairs of L5 and CA3 pyramidal neurons is determined by the presynaptic release probability (Pr): synaptic latency being inversely correlated with the amplitude of the postsynaptic current and sensitive to manipulations of Pr. Changes in synaptic latency were also observed when Pr was physiologically regulated in short- and long-term synaptic plasticity. Paired-pulse depression and facilitation were respectively associated with increased and decreased synaptic latencies. Similarly, latencies were prolonged following induction of presynaptic LTD and reduced after LTP induction. We show using the dynamic-clamp technique that the observed covariation in latency and synaptic strength is a synergistic combination that significantly affects postsynaptic spiking. In conclusion, amplitude-related variation in latency represents a putative code for short- and long-term synaptic dynamics in cortical networks.  相似文献   

20.
Changes in the antioxidative enzyme activities (SOD, CuZnSOD, GSH-Px, GST), as well as TBARS content in 5-week-old tomato (Lycopersicon esculentum Mill. cv “Perkoz”) roots were examined 1, 3 h (short-term stress) and 1–14 days (long-term stress) after a single application of 50 mM (mild stress) and 150 mM NaCl (severe stress). The severe stress caused an increase in GST, GSH-Px and SODs activities from the beginning of the experiment while mild stress induced enhancement of GST activity from the second day of experiment. The maximum increase in SODs after both NaCl solutions were applied and in GST activity after the higher NaCl dose on the second day of the experiment was observed. Moreover, after 1 h of NaCl treatment with both tested NaCl solutions, the highest induction of GSH-Px activity appeared. TBARS content was elevated from the first hour of salt stress and decreased only 14 days after 50 mM NaCl application which was accompanied by high induction of GSH-Px activity. In conclusion, enhanced activities of tested enzymes indicate their involvement in early and late defence systems under salinity stress. Moreover, the dynamics of the changes in the antioxidant enzymes suggests that the second day following NaCl application is a crucial moment of the experiment with regard to salt-mediated oxidative stress.  相似文献   

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