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111.
112.
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   
113.
Parallel follow-up of clinical and inflammatory markers during sub-lingual immunotherapy (SLIT) is highly beneficial. Twenty-four children (age 4-16) monosensitized to house dust mite were randomized to receive either active or placebo SLIT for 1 yr in a double-blind placebo controlled design (Marcucci et al., Allergy 2003: 58: 657-62). Thereafter, for 2 yr they all received active treatment. Symptom scores for rhinitis, asthma, and drug usage were daily recorded. Eosinophil cationic protein (ECP) and tryptase in sputum and nasal secretions, serum and nasal mite-specific immunoglobulin E (IgE) were recorded before treatment and at 10-12 months intervals. Nasal ECP and nasal tryptase after specific nasal provocation tests were significantly reduced as compared to baseline values (p = 0.0043 and 0.0195, respectively) in the third year of active treatment. None of the other inflammatory parameters was increased. In placebo treated patients all these parameters tended to decrease only after switching to active treatment. Clinical scores did not improve in treated vs. placebo patients in the double-blind placebo-controlled phase of the study. In both cohorts a clinical benefit was observed as intra-group score reduction as compared to baseline. A significant difference was reached in patients treated for 2 yr for rhinitis and asthma (p = 0.0009 and 0.0019, respectively) but not for drug usage and in patients treated for 3 yr for rhinitis, asthma, and drug usage (p = 0.0105, 0.0048, and 0.02, respectively). SLIT in children monosensitized to mites reverted the spontaneous increase in nasal IgE and in local parameters of allergic inflammation. These outcomes were followed by a consolidated clinical improvement in the second and third year of treatment.  相似文献   
114.
The relationship was analyzed between cell kinetics, defined as 3H-thymidine labeling index (3H-TdR LI), and clinical responses for 35 previously untreated patients with locally advanced oral cavity squamous cell carcinomas. Patients were treated with three cycles of vincristine and bleomycin (VB) or of VB plus methotrexate (VBM), given by intra-arterial infusion followed by surgery. The objective clinical response rate was higher after VBM treatment than after VB, whereas overall clinical response rates were similar for patients with slowly or rapidly proliferating tumors. The probability of relapse-free survival at 4 yr and overall survival was significantly higher for patients with high 3H-TdR LI tumors given VBM than for those given VB. For patients with slowly proliferating tumors, there were no differences in relapse-free survival and overall survival between the two treatments. These data suggest that patients with rapidly proliferating tumors benefit from primary intensive chemotherapy treatment including methotrexate and that cell kinetics can be used to formulate rational clinical protocols for oral cavity cancers.  相似文献   
115.
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   
116.

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   
117.

Introduction

Severe sepsis is the leading cause of mortality in critically ill patients. Abnormal concentrations of inflammatory mediators appear to be involved in the pathogenesis of sepsis. Based on the humoral theory of sepsis, a potential therapeutic approach involves high-volume haemofiltration (HVHF), which has exhibited beneficial effects in severe sepsis, improving haemodynamics and unselectively removing proinflammatory and anti-inflammatory mediators. However, concerns have been expressed about the feasibility and costs of continuous HVHF. Here we evaluate a new modality, namely pulse HVHF (PHVHF; 24-hour schedule: HVHF 85 ml/kg per hour for 6–8 hours followed by continuous venovenous haemofiltration 35 ml/kg per hour for 16–18 hours).

Method

Fifteen critically ill patients (seven male; mean Acute Physiology and Chronic Health Evaluation [APACHE] II score 31.2, mean Simplified Acute Physiology Score [SAPS] II 62, and mean Sequential Organ Failure Assessment 14.2) with severe sepsis underwent daily PHVHF. We measured changes in haemodynamic variables and evaluated the dose of noradrenaline required to maintain mean arterial pressure above 70 mmHg during and after pulse therapy at 6 and 12 hours. PHVHF was performed with 250 ml/min blood flow rate. The bicarbonate-based replacement fluid was used at a 1:1 ratio in simultaneous pre-dilution and post-dilution.

Results

No treatment was prematurely discontinued. Haemodynamics were improved by PHVHF, allowing a significant reduction in noradrenaline dose during and at the end of the PHVHF session; this reduction was maintained at 6 and 12 hours after pulse treatment (P = 0.001). There was also an improvement in systolic blood pressure (P = 0.04). There were no changes in temperature, cardiac index, oxygenation, arterial pH or urine output during the period of observation. The mean daily Kt/V was 1.92. Predicted mortality rates were 72% (based on APACHE II score) and 68% (based on SAPS II score), and the observed 28-day mortality was 47%.

Conclusion

PHVHF is a feasible modality and improves haemodynamics both during and after therapy. It may be a beneficial adjuvant treatment for severe sepsis/septic shock in terms of patient survival, and it represents a compromise between continuous renal replacement therapy and HVHF.  相似文献   
118.
119.
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   
120.
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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