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81.
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OBJECTIVE: Evidence suggests increased morbidity, in particular early neonatal respiratory complications, in newborns from elective cesarean section compared with those from vaginal delivery. No reliable maternal predictors of adverse neonatal outcome at elective cesarean section are known. Here, we prospectively tested the hypothesis that a low maternal perfusion index at the baseline phase (i.e., preanesthesia) of the elective cesarean section is a predictor of early adverse neonatal respiratory outcome. DESIGN: Prospective cohort study. SETTING: Operating and delivery rooms of a public health hospital with a tertiary-level neonatal intensive care unit. PATIENTS: Forty-four healthy pregnant women with no known risk factors undergoing elective cesarean section at term gestation. INTERVENTIONS: Elective cesarean section was divided into nine phases. Analysis of pulse oximetry-derived signals (perfusion index, pulse rate, and oximetry) and systolic, diastolic, and differential blood pressure were recorded. Maternal arterial and venous newborn cord blood gas analyses and placental histology were evaluated. MEASUREMENTS AND MAIN RESULTS: Early respiratory complications (transient tachypnea of the newborn, n = 5; respiratory distress syndrome, n = 1) were observed in 13.6% (6 of 44) of the newborns. A maternal perfusion index < or = 1.9 (lower quartile) during the preanesthesia phase of the elective cesarean section was an independent predictor of early adverse neonatal respiratory outcome (odds ratio 68.0, 95% confidence interval 6.02-767.72; p < .0001). CONCLUSIONS: A decreased perfusion index value in the preanesthesia phase of elective cesarean section is a maternal predictor of increased neonatal morbidity and is significantly related to subclinical placental inflammatory disease. These observations suggest the feasibility of a noninvasive pulse oximeter prenatal screening of the high-risk fetus/newborn in elective cesarean section.  相似文献   
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Of unknown pathogenesis, sponge kidney (SK) is variably associated with nephrocalcinosis, stones, nephronic tubule dysfunctions and precalyceal duct cysts. Amongst 72 unrelated renal SK patients with renal stone disease, we detected one with unilateral bifid renal pelvis and six with unilateral small kidneys (longitudinal diameter difference >15%). Secondary causes of small kidney were excluded. Of the seven cases, four had reduced renal function (67 vs 7% in the entire cohort), and three developed hyperparathyroidism during follow-up (43 vs 4%). The pathogenesis of SK ought to explain why anatomical structures of different embryological origin are involved (the precalyceal and collecting ducts and the nephron) and why there is frequent association with hyperparathyroidism. In embryogenesis, the metanephric blastema synthesizes the chemotactic glial-derived neurotrophic factor (GDNF) to prompt the ureteric bud to branch off from Wolff's mesonephric duct, and to approach and invade the blastema. The bud's tip expresses the GDNF receptor (RET). RET-GDNF binding is crucial not only for the correct formation of ureters and collecting ducts (both of Wolffian origin), but also for nephrogenesis. We advance the hypothesis that SK results from a disruption in the ureteric bud-metanephric blastema interface, possibly due to one or more mutations or polymorphisms of RET or GDNF genes. This would explain: the concurrent alterations in precalyceal ducts and the functional defects in the nephron, the occasional association with size and the functional asymmetry between the two kidneys, some degree of renal dysplasia causing the reduction in the glomerular filtration rate and (given the role of RET in parathyroid cell proliferation) the association with hyperparathyroidism.  相似文献   
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Bardet–Biedl syndrome (BBS) is a rare pleiotropic disorder known as a ciliopathy. Despite significant genetic heterogeneity, BBS1 and BBS10 are responsible for major diagnosis in western countries. It is well established that eight BBS proteins, namely BBS1, 2, 4, 5, 7, 8, 9, and 18, form the BBSome, a multiprotein complex serving as a regulator of ciliary membrane protein composition. Less information is available for BBS6, BBS10, and BBS12, three proteins showing sequence homology with the CCT/TRiC family of group II chaperonins. Even though their chaperonin function is debated, scientific evidence demonstrated that they are required for initial BBSome assembly in vitro. Recent studies suggest that genotype may partially predict clinical outcomes. Indeed, patients carrying truncating mutations in any gene show the most severe phenotype; moreover, mutations in chaperonin-like BBS proteins correlated with severe kidney impairment. This study is a critical review of the literature on genetics, expression level, cellular localization and function of BBS proteins, focusing primarily on the chaperonin-like BBS proteins, and aiming to provide some clues to understand the pathomechanisms of disease in this setting.  相似文献   
87.

Purpose

Good communication between ICU staff and patients’ relatives may reduce the occurrence of post-traumatic stress disorder, anxiety or depression, and dissatisfaction with clinicians. An information brochure and website to meet relatives’ needs were designed to explain in technical yet simple terms what happens during and after an ICU stay, to legitimize emotions such as fear, apprehension, and suffering, and to improve cooperation with relatives without increasing staff workload. The main outcomes were improved understanding of prognosis and procedures, and decrease of relatives’ anxiety, depression, and stress symptoms.

Methods

In this prospective multicenter before-and-after study, a self-administered questionnaire was used to investigate relatives’ understanding of prognosis, treatments, and organ dysfunction, families’ satisfaction, and symptoms of anxiety, depression, and post-traumatic stress.

Results

A total of 551 relatives received questionnaires in nine Italian ICUs; 332 (60%) responded, 144 before and 179 after implementation of the brochure and website. Of the 179 relatives who responded after, 131 (73%) stated they had read the brochure and 34 (19%) reported viewing the website. The intervention was associated with increased correct understanding of the prognosis (from 69 to 84%, p = 0.04) and the therapeutic procedures (from 17 to 28%, p = 0.03). Multivariable analysis, together with non-modifiable factors (relative’s gender, education level, relationship to patient, and patient status at ICU discharge), showed the intervention to be significantly associated with a lower incidence of post-traumatic stress symptoms (Poisson coefficient = ?0.29, 95% CI ?0.52/?0.07). The intervention had no effect on the prevalence of symptoms of anxiety and depression.

Conclusion

An information brochure and website designed to meet relatives’ needs improved family members’ comprehension and reduced their prevalence of stress symptoms.
  相似文献   
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BACKGROUND: Lormetazepam is a hypnotic benzodiazepine currently used in the treatment of insomnia. When this agent is used appropriately, its pharmacologic properties predict a high therapeutic index with a good tolerability profile. OBJECTIVE: The primary aim of this study was to compare the effects on psychomotor performance of lormetazepam and placebo in healthy young adult subjects. A secondary objective was to evaluate the clinical tolerability of lormetazepam. METHODS: This was a randomized, double-blind,placebo-controlled, crossover study in healthy young adult volunteers. All volunteers received single doses of lormetazepam 1 mg and placebo, with a 1-week interval between doses. The primary study variables were visual simple reaction time (VSRT) and visual choice reaction time (VCRT), measured before dosing with lormetazepam or placebo and at 20, 60, 120, 180, 240, and 360 minutes after dosing using a standard computerized apparatus. To increase the sensitivity of the results, visual reaction times were also recorded using a validated mobile computerized device. Secondary variables were the duration and quality of sleep on the night before each study session, rated by subjects using a 100-mm visual analog scale; the Epworth Sleepiness Scale for daytime drowsiness; and the Critical Flicker Fusion Threshold test. Spontaneously reported adverse events were recorded and monitored throughout the study. RESULTS: The study included 18 healthy young adult volunteers (12 women, 6 men; mean [SD] age, 26.7 [2.8] years [range, 21-30 years]; mean body weight, 58 [9.5] kg). There were no significant differences in either VSRT or VCRT after administration of lormetazepam or placebo. Independent of study drug but consistent with the accepted range of variability between the 2 devices, overall reaction times were significantly shorter with the use of the mobile device compared with the standard apparatus (P < 0.01). Analysis of the results showed no sequence effects or other evidence of learning. There were no changes in the secondary study variables after administration of the test drugs. Administration of lormetazepam was associated with dizziness in 2 subjects, in 1 case occurring in association with somnolence. These adverse events were mild and subsided spontaneously 3 hours after drug intake. After administration of placebo, 1 subject reported slight somnolence 60 minutes after dosing that persisted through 180 minutes. CONCLUSION: In this small, selected group of healthy young adult subjects, a single dose of lormetazepam 1 mg did not affect psychomotor performance, assessed in terms of visual reaction times, compared with placebo.  相似文献   
90.
Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is a frequent and severe chronic disease drastically impairing life quality. The underlying pathomechanism is incompletely understood yet but there is convincing evidence that in at least a subset of patients ME/CFS has an autoimmune etiology. In this review, we will discuss current autoimmune aspects for ME/CFS. Immune dysregulation in ME/CFS has been frequently described including changes in cytokine profiles and immunoglobulin levels, T- and B-cell phenotype and a decrease of natural killer cell cytotoxicity. Moreover, autoantibodies against various antigens including neurotransmitter receptors have been recently identified in ME/CFS individuals by several groups. Consistently, clinical trials from Norway have shown that B-cell depletion with rituximab results in clinical benefits in about half of ME/CFS patients. Furthermore, recent studies have provided evidence for severe metabolic disturbances presumably mediated by serum autoantibodies in ME/CFS. Therefore, further efforts are required to delineate the role of autoantibodies in the onset and pathomechanisms of ME/CFS in order to better understand and properly treat this disease.  相似文献   
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