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91.
Mucopolysaccharidosis (MPS) I is a lysosomal storage disorder (LSD) that is characterised by alpha-L-iduronidase (Idua) deficiency and continuous deposition of glycosaminoglycans (GAGs), which consequently interferes with cell signalling mechanisms and results in multisystemic and progressive symptoms. The animal model of MPS I (Idua-/-) has been widely studied to elucidate the consequences and progression of the disorder; however, studies specifically assessing the male reproductive tract are lacking. The aim of this study was to evaluate some of the reproductive characteristics of male MPS I mice in two phases of life. Reproductive organ biometry, sperm counts, sperm morphological evaluation, plasma testosterone measurements and histopathological, histomorphometrical and immunohistochemical analysis were performed in 3- and 6-month-old C57BL/6 Idua+/+ and Idua-/- mice. Seminal vesicle weights were decreased in both the 3- and 6-month-old Idua-/- mice. Decrease in sperm counts and the majority of the histopathological signs were observed in the 6-month-old Idua-/- mice. No differences were detected in the sperm morphological analysis. Immunohistochemistry revealed that seminiferous tubules from 3-month-old Idua-/- mice were more intensely stained with anti-caspase-3 than 3-month-old Idua+/+ mice, but no difference was found at 6 months. These results suggest that MPS I interferes with male reproductive parameters both in 3 and 6-month-old animals and histopathological signs are more pronounced in 6-month-old mice, indicating that the effects of the disorder may intensify with the disease progression.  相似文献   
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The purpose of this study was to determine the effect of respiratory muscle fatigue on intercostal and forearm muscle perfusion and oxygenation in patients with heart failure. Five clinically stable heart failure patients with respiratory muscle weakness (age, 66±12 years; left ventricle ejection fraction, 34±3%) and nine matched healthy controls underwent a respiratory muscle fatigue protocol, breathing against a fixed resistance at 60% of their maximal inspiratory pressure for as long as they could sustain the predetermined inspiratory pressure. Intercostal and forearm muscle blood volume and oxygenation were continuously monitored by near-infrared spectroscopy with transducers placed on the seventh left intercostal space and the left forearm. Data were compared by two-way ANOVA and Bonferroni correction. Respiratory fatigue occurred at 5.1±1.3 min in heart failure patients and at 9.3±1.4 min in controls (P<0.05), but perceived effort, changes in heart rate, and in systolic blood pressure were similar between groups (P>0.05). Respiratory fatigue in heart failure reduced intercostal and forearm muscle blood volume (P<0.05) along with decreased tissue oxygenation both in intercostal (heart failure, -2.6±1.6%; controls, +1.6±0.5%; P<0.05) and in forearm muscles (heart failure, -4.5±0.5%; controls, +0.5±0.8%; P<0.05). These results suggest that respiratory fatigue in patients with heart failure causes an oxygen demand/delivery mismatch in respiratory muscles, probably leading to a reflex reduction in peripheral limb muscle perfusion, featuring a respiratory metaboreflex.  相似文献   
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Introduction: Preeclampsia (PE) is a systemic inflammatory disease, and its effect on human milk immune components is poorly understood.

Objective: To investigate whether PE affects human milk cytokine levels.

Methods: This was a prospective observational study involving mothers diagnosed with PE and with singleton pregnancy with no fetal malformation. The following cases were excluded: diabetes, chorioamnionitis, use of illicit drugs and alcohol, mastitis and congenital infection. In total, 228 mothers were studied and divided into two groups matched by gestational age: PE (n?=?114) and normotensive (control, n?=?114). Colostrum was collected from 24–72?hours postpartum, and mature milk was collected at the end of the first month. Cytokines (IL-1β, IL-6, IL-8, IL-10, IL-12, and TNF-α) were measured using flow cytometry. A generalized linear model with a gamma distribution was used to analyze the differences between groups versus time interaction.

Results: The mean gestational age was 36 weeks. Increased IL-1 and IL-6 levels and reduced IL-12 levels in the colostrum were detected in PE, while in the mature milk, the IL-6 and IL-8 levels were lower than those of the control group.

Conclusions: PE is associated with increased levels of inflammatory cytokines in colostrum and decreased levels in mature milk.  相似文献   
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OBJECTIVE: To make pediatricians aware of ideas about how to handle head injury in children under and over 2 years of age, to facilitate understanding and to allow a rethinking about the necessary care when attending children with head injury. SOURCES: A bibliographic review of the theme based on Medline. SUMMARY OF THE FINDINGS: The following aspects were analyzed: the overall epidemiological aspects, the concept and the physiopathology of the damage caused by brain trauma. The assessment of the severity of head injury for different age ranges was discussed, as well as the opinion of various authors and the current ideas about the criteria regarding hospitalization, request for supplementary exams and therapeutic approach. The value of neuroimaging exams in cases of head injury and, finally, the prevention strategies and conclusions also were discussed. CONCLUSIONS: In most cases, head injuries in children are rated as not being severe. Nevertheless, even though they are seen as slight, when considering the pediatric population the clinical picture is often asymptomatic presenting neuroimaging changes, the management of head injury at this age range is different from the management in adults.  相似文献   
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Background

Approximately 5–10 % of newborns require some form of resuscitationupon delivery; several factors, such as maternal abnormal conditions, gestational age and type of delivery could be responsible for this trend. This study aimed to describe the factors associated with the need for positive pressure ventilation (PPV) via a mask or endotracheal tube and the use of supplemental O2 in newborns with a gestational age greater than 34 weeks in Brazil.

Methods

We performed a cross-sectional study and obtained data from the Birth in Brazil Survey. The inclusion criterion was a gestational age ≥34 weeks. Exclusion criteria were newborns with congenital malformations, and cases with undetermined gestational age or type of delivery (vaginal, pre labor cesarean section and cesarean section during labor). The primary outcomes were need of PPV via a mask or endotracheal tube and the use of supplemental oxygen without PPV. Confounding variables, including maternal age, source of birth payment, years of maternal schooling, previous birth, newborn presentation, multiple pregnancy, and maternal obstetric risk, were analyzed.

Results

We included 22,720 newborns. Of these, 2974 (13.1 %) required supplementary oxygen. PPV with a bag and mask was used for 727 (3.2 %) newborns and tracheal intubation for 192 (0.8 %) newborns. Chest compression was necessary for 136 (0.6 %) newborns and drugs administered in 114 (0.5 %). 51.3 % of newborns were delivered by cesarean section, with the majority of cesarean sections (88.7 %) being performed prior to labor. Gestational age (late preterm infants: (Relative Risk-(RR) 2.46; 95 % (Confidence interval-CI 1.79–3.39), maternal obstetric risk (RR 1.59; 95 % CI1.30–1.94), and maternal age of 12–19 years old (RR 1.36; 95 % CI1.06–1.74) contributed to rates of PPV in the logistic regression analysis. Newborns aged between 37–38 weeks of gestaional age weren´t less likely to require PPV compared with those aged 39–41 weeks of gestational age.

Conclusions

Late preterm infants, previous maternal obstetric risks and maternal age contributed to the higher needs of PPV and use of O2 in the delivery room. These variables need to be considered in planning care in the delivery room.
  相似文献   
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