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81.
ObjectiveChildren admitted to the intensive care unit (ICU) are at risk of inadequate energy intake. Although studies have identified factors contributing to an inadequate energy supply in critically ill children, they did not take into consideration the length of time during which patients received their estimated energy requirements after having achieved a satisfactory energy intake. This study aimed to identify factors associated with the non-attainment of estimated energy requirements and consider the time this energy intake is maintained.MethodsThis was a prospective study involving 207 children hospitalized in the ICU who were receiving enteral and/or parenteral nutrition. The outcome variable studied was whether 90% of the estimated basal metabolic rate was maintained for at least half of the ICU stay (satisfactory energy intake). The exposure variables for outcome were gender, age, diagnosis, use of vasopressors, malnutrition, route of nutritional support, and Pediatric Index of Mortality and Pediatric Logistic Organ Dysfunction scores.ResultsSatisfactory energy intake was attained by 20.8% of the patients, within a mean time of 5.07 ± 2.48 d. In a multivariable analysis, a diagnosis of heart disease (odds ratio 3.62, 95% confidence interval 1.03–12.68, P = 0.045) increased the risk of insufficient energy intake, whereas malnutrition (odds ratio 0.43, 95% confidence interval 0.20–0.92, P = 0.030) and the use of parenteral nutrition (odds ratio 0.34, 95% confidence interval 0.15–0.77, P = 0.001) were protective factors against this outcome.ConclusionA satisfactory energy intake was reached by a small proportion of patients during their ICU stay. Heart disease was an independent risk factor for the non-attainment of satisfactory energy intake, whereas malnutrition and the use of parenteral nutrition were protective factors against this outcome.  相似文献   
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HIV-1 negative factor (Nef) elevates virus replication and contributes to immune evasion in vivo. As one of its established in vitro activities, Nef interferes with T-lymphocyte chemotaxis by reducing host cell actin dynamics. To explore Nef’s influence on in vivo recirculation of T lymphocytes, we assessed lymph-node homing of Nef-expressing primary murine lymphocytes and found a drastic impairment in homing to peripheral lymph nodes. Intravital imaging and 3D immunofluorescence reconstruction of lymph nodes revealed that Nef potently impaired T-lymphocyte extravasation through high endothelial venules and reduced subsequent parenchymal motility. Ex vivo analyses of transendothelial migration revealed that Nef disrupted T-lymphocyte polarization and interfered with diapedesis and migration in the narrow subendothelial space. Consistently, Nef specifically affected T-lymphocyte motility modes used in dense environments that pose high physical barriers to migration. Mechanistically, inhibition of lymph node homing, subendothelial migration and cell polarization, but not diapedesis, depended on Nef’s ability to inhibit host cell actin remodeling. Nef-mediated interference with in vivo recirculation of T lymphocytes may compromise T-cell help and thus represents an important mechanism for its function as a HIV pathogenicity factor.  相似文献   
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ObjectiveOne hundred thirty-one cases of postsurgical infections were reported in Southern Region of Brazil between August 2007 and January 2008. Thirty-nine (29.8%) cases were studied; this report describes epidemiological findings, species identification, antimicrobial susceptibility and clonal diversity of rapidly growing mycobacteria isolated in this outbreak.MethodsAll 39 isolates were analyzed by Ziehl-Nielsen stained smear, bacterial culture and submitted to rpoB partial gene sequencing for identification. The isolates were also evaluated for their susceptibility to amikacin, cefoxitin, clarithromycin, ciprofloxacin, doxycycline, tobramycin and sulfamethoxazole.ResultsThirty-six isolates out of the confirmed cases were identified as Mycobacterium massiliense and the remaining three were identified as Mycobacterium abscessus, Mycobacterium chelonae and Mycobacterium fortuitum. All M. massiliense isolates were susceptible to amikacin (MIC90 = 8 μg/mL) and clarithromycin (MIC90 = 0.25 μg/mL) but resistant to cefoxitin, ciprofloxacin, doxycycline, tobramycin and sulfamethoxazole. Molecular analysis by pulsed-field gel electrophoresis clustered all 36 M. massiliense isolates and showed the same pattern (BRA 100) observed in three other outbreaks previously reported in Brazil.ConclusionsThese findings suggest a common source of infection for all patients and reinforce the hypotheses of spread of M. massiliense BRA100 in Brazilian hospital surgical environment in recent years.  相似文献   
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Kallmann syndrome (KS) is a developmental disease characterized by the association of isolated hypogonadotropic hypogonadism and anosmia/hyposmia. We report an unusual presentation of two females with KS and empty sella. These females, aged at 20 and 29-year-old, presented primary amenorrhea with prepubertal estradiol and low gonadotropin levels. No other significant clinical signs were observed. Empty sella was observed on MRI in both cases. Sequencing of FGFR1 gene, recently implicated in autosomal form of KS, was performed and one splicing mutation (IVS14 + 1G > A) was identified in one patient.  相似文献   
87.
In this study we assessed neonatal complications of diabetic in 50 pregnant women at a University Hospital during 2001-2002: 13 (26%) with type 1 diabetes (DM1), 16 with DM2, and 21 (42%) with gestational DM (GDM). The mean outpatient follow-up was at 16.3+/-8 wk for patients with DM1, 22.9+/-7.5 wk for DM2, and 26.0+/-8.9 wk for GDM. Mean HbA1c, fasting and 2-h post-prandial glycemia on first attendance were respectively: 6.1+/-1,1% (RV: 2.6-6.2%), 132+/-39 mg/dL and 190+/-54 mg/dL. 22 patients were on insulin and 15 were on oral antidiabetic agents (OA) at first evaluation. OA were taken on conception and during the first pregnancy trimester and no malformations were seen in the children. Their metabolic profile was similar to other pregnant women. Caesarean section was needed in 54.5% of deliveries. Complications: 56.1% were macrosomic babies, with a mean fetal weight of 3.48+/-0.73 Kg, with no differences according to treatment (insulin vs. OA). We conclude that diabetic pregnant women begin their prenatal care at a later period, often taking OA that are not officially advised to be used during pregnancy and are not in a regular metabolic control. As a result, they have macrosomic infants. Even though we have found no complications related to the OA use during pregnancy, we should not encourage their use until more safety studies are available.  相似文献   
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Metabolic Brain Disease - Acetylcholine is an excitatory neurotransmitter that modulates synaptic plasticity and communication, and it is essential for learning and memory processes. This...  相似文献   
90.

Purpose of Review

To review and discuss the epidemiology, risk factors, clinical presentation, diagnosis, and treatment of non-tuberculous mycobacteria (NTM) in thoracic transplantation.

Recent Findings

Non-tuberculous mycobacteria are ubiquitous but are an uncommon cause of disease after solid organ transplantation. The incidence of infection is higher in thoracic transplant recipients than in abdominal transplant recipients, with most cases seen after lung transplantation. It is associated with increased morbidity and, occasionally, mortality. Infection in the pre-transplant setting can occur in lung transplant candidates, often posing a dilemma regarding transplant listing. Disease manifestations are diverse, and pulmonary disease is the most common. Diagnosis requires a high index of suspicion. Treatment requires a multiple-drug combination and is limited by drug-drug interactions and tolerability. Mycobacterium abscessus is a challenge in lung transplant recipients, due to its intrinsic resistance and propensity to relapse even after prolonged therapy. Mycobacterium chimaera is an emerging pathogen associated with contamination of heater-cooler units and is described to cause disease months after cardiothoracic surgery.

Summary

NTM infections in thoracic organ transplant recipients are uncommon but are associated with substantial morbidity and mortality. Data from larger multicenter studies is needed to better define the epidemiology of NTM in thoracic transplantation, best treatment options, and the management of infected transplant candidates.
  相似文献   
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