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991.

Objective

Higher serum melatonin levels have previously been found in patients with severe sepsis who died within 30 days of diagnosis than in survivors. The objective of our study were to determine whether serum melatonin levels during the first seven days of severe sepsis diagnosis could be associated with sepsis severity and mortality.

Methods

Multicentre study in eight Spanish Intensive Care Units which enrolled 308 patients with severe sepsis. We determined serum levels of melatonin, malondialdehyde (as biomarker of lipid peroxidation) and tumor necrosis factor-alpha at days 1, 4 and 8 of severe sepsis diagnosis. The study's primary endpoint was 30-day mortality.

Results

A total of 103 patients had died and 205 survived at 30 days of severe sepsis diagnosis, with the non-survivors presenting higher serum melatonin levels at days 1 (p < 0.001), 4 (p < 0.001) and 8 (p < 0.001) of severe sepsis diagnosis than the survivor patient group. The multiple logistic regression analysis found that serum melatonin levels at days 1, 4 and 8 of severe sepsis diagnosis (p < 0.001, p = 0.01 and p = 0.001, respectively) were associated with mortality adjusted for age, serum lactic acid, SOFA score and diabetes mellitus.

Conclusions

The novel and more interesting findings of our study were that serum melatonin levels during the first seven days of severe sepsis diagnosis are associated with sepsis severity and mortality.  相似文献   
992.
993.
In many countries, M1 strains of the human pathogenic bacterium group A Streptococcus are the most common serotype recovered from patients with invasive disease episodes. Strains of this serotype express an extracellular protein that inhibits complement [streptococcal inhibitor of complement (Sic)] and is therefore believed to be a virulence factor. Comparative sequence analysis of the 915-bp sic gene in 165 M1 organisms recovered from diverse localities and infection types identified 62 alleles. Inasmuch as multilocus enzyme electrophoresis and pulsed-field gel electrophoresis previously showed that most M1 organisms represent a distinct streptococcal clone, the extent of sic gene polymorphism was unexpected. The level of polymorphism greatly exceeds that recorded for all other genes examined in serotype M1 strains. All insertions and deletions are in frame, and virtually all nucleotide substitutions alter the amino acid sequence of the Sic protein. These molecular features indicate that structural change in Sic is mediated by natural selection. Study of 70 strains recovered from two temporally distinct epidemics of streptococcal infections in the former East Germany found little sharing of Sic variants among strains recovered in the different time periods. Taken together, the data indicate that sic is a uniquely variable gene and provide insight into a potential molecular mechanism contributing to fluctuations in streptococcal disease frequency and severity.  相似文献   
994.
Renal denervation and spironolactone have both been proposed for the treatment of resistant hypertension, but their effects on preclinical target organ damage have not been compared. Twenty‐four patients with 24‐hour systolic blood pressure ≥140 mm Hg despite receiving three or more full‐dose antihypertensive drugs, one a diuretic, were randomized to receive spironolactone or renal denervation. Changes in 24‐hour blood pressure, urine albumin excretion, arterial stiffness, carotid intima‐media thickness, and left ventricular mass index were evaluated at 6 months. Mean baseline‐adjusted difference between the two groups (spironolactone vs renal denervation) at 6 months in 24‐hour systolic blood pressure was −17.9 mm Hg (95% confidence interval [CI], −30.9 to −4.9; P = .01). Mean baseline‐adjusted change in urine albumin excretion was −87.2 (95% CI, −164.5 to −9.9) and −23.8 (95% CI, −104.5 to 56.9), respectively (= .028). Mean baseline‐adjusted variation of 24‐hour pulse pressure was −13.5 (95% CI, −18.8 to −8.2) and −2.1 (95% CI, −7.9 to 3.7), respectively (= .006). The correlation of change in 24‐hour systolic blood pressure with change in log‐transformed urine albumin excretion was = .713 (< .001). At 6 months there was a reduction in albuminuria in patients with resistant hypertension treated with spironolactone as compared with renal denervation.  相似文献   
995.
996.
The sequence of events associated with the development of gastric cancer has been described as “the gastric precancerous cascade”. This cascade is a dynamic process that includes lesions, such as atrophic gastritis, intestinal metaplasia and dysplasia. According to this model, Helicobacter pylori (H. pylori) infection targets the normal gastric mucosa causing non-atrophic gastritis, an initiating lesion that can be cured by clearing H. pylori with antibiotics or that may then linger in the case of chronic infection and progress to atrophic gastritis. The presence of virulence factors in the infecting H. pylori drives the carcinogenesis process. Independent epidemiological and animal studies have confirmed the sequential progression of these precancerous lesions. Particularly long-term follow-up studies estimated a risk of 0.1% for atrophic gastritis/intestinal metaplasia and 6% in case of dysplasia for the long-term development of gastric cancer. With this in mind, a better understanding of the genetic and epigenetic changes associated with progression of the cascade is critical in determining the risk of gastric cancer associated with H. pylori infection. In this review, we will summarize some of the most relevant mechanisms and focus predominantly but not exclusively on the discussion of gene promoter methylation and miRNAs in this context.  相似文献   
997.

Oxidative stress and damage are pivotal in the pathophysiology of diabetic retinopathy. A diet abundant in plants and the performance of non-exhaustive exercise are proposed as potential strategies against diabetic retinopathy. We aimed to determine if any of them protect against diabetic retinopathy. Eighty-eight diabetic patients were asked about their frequency of consumption of vegetables and fruits and about the intensity, length, and frequency of their exercising. Age, weight, chest and waist circumferences, height, body mass index, recent weight loss, known duration of diabetes, family history of diabetes, presence of another chronic disease, last acute disease, history of herpes infection, smoking, consumption of alcohol, hypoglycemic agents, anti-inflammatories, vitamin supplements and hormones, periodontal disease, inflammation, and psychological stress were also surveyed. Twenty-two patients were diagnosed with diabetic retinopathy. Statistical analyses were performed to assess its correlation with these parameters. No associations were found for a diet abundant in vegetables and fruits or for the performance of any intensity of exercise, but for the use of insulin (odds ratio = 3.750, 95 % confidence interval = 1.317–10.681) and for the known duration of diabetes (odds ratio = 1.198, 95 % confidence interval = 1.098–1.306). Our research found a lack of protection of a diet abundant in vegetables and fruits and of non-exhaustive exercise against diabetic retinopathy.

  相似文献   
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999.
1000.
Clinical practice guidelines (CPGs) contain evidence‐based recommendations to guide clinical care, policy development, and quality of care improvement. A recent systematic review of epilepsy guidelines identified considerable variability in the quality of available guidelines. Although excellent frameworks for CPG development exist, processes are not followed uniformly internationally, and resources to develop CPGs may be limited in certain settings. An International League Against Epilepsy (ILAE) working group was charged with proposing methodology to guide the development of future epilepsy‐specific CPGs. A comprehensive literature search (1985–2014) identified articles related to CPG development and handbooks. Guideline handbooks were included if they were publicly available, and if their methodology had been used to develop CPGs. The working group's expertise also informed the creation of methodologies and processes to develop future CPGs for the ILAE. Five handbooks from North America (American Academy of Neurology), Europe (Scottish Intercollegiate Guidelines Network & National Institute for Health and Care Excellence), Australia (National Health and Medical Research Council), World Health Organization (WHO), and additional references were identified to produce evidence‐based, consensus‐driven methodology for development of epilepsy‐specific CPGs. Key components of CPG development include the following: identifying the topic and defining the scope; establishing a working group; identifying and evaluating the evidence; formulating recommendations and determining strength of recommendations; obtaining peer reviews; dissemination, implementation, and auditing; and updating and retiring the CPG. A practical handbook and toolkit was developed. The resulting CPG development toolkit should facilitate the development of high‐quality ILAE CPGs to improve the care of persons with epilepsy.  相似文献   
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