雾化吸入对新生儿肺炎患儿血氧饱和度的影响

采用动脉血氧饱和度仪对５２例新生儿肺炎患儿，在雾化吸入治疗过程中的动脉血氧饱和度（ＳａＯ２）进行了监测，对比了吸氧与否对ＳａＯ２改变的影响。结查表明：与基础值比较，雾化吸入时患儿的ＳａＯ２显著下降（Ｐ＜０．０１），而雾化吸入同时吸氧者ＳａＯ２无明显变化（Ｐ＞０．０５），但两者比较具有显著性差异（Ｐ＜０．０１）。结果提示雾化吸入可使新生儿肺炎患儿ＳａＯ２下降；同时吸氧，对防止ＳａＯ２的下降有一定作用。     

Early and late onset bacteremia have different risk factors in trauma patients

Objective The aim of this study was to identify risk factors and to describe epidemiological patterns for early—(EOB) and late—onset bacteremias (LOB) after trauma.Design A prospective study conducted on 141 consecutive trauma patients.Setting A general intensive care unit (ICU) of a university hospital.Patients All multiple trauma patients admitted to our general intensive care unit (ICU) from December 1990 to May 1992 were prospectively enrolled in the study. The following information was collected for each patient and recorded in a computer database: demography, severity of trauma according to the Abbreviated Injury Scale (AIS), severtity of trauma according to the Glasgow Coma Scale (GCS), presence of pneumothorax, pulmonary contusion, rib fractures, hemothorax, and abdominal trauma, use of mechanical ventilation, and placement of central venous catheters. Bacteremias were defined as EOB when onset occurred within 96 h after trauma, and as LOB when appearing after 96 h from trauma.Results Thirty-seven patients developed bacteremia during their ICU stay (26%): 11 (29.7%) EOB and 26 (70.3%) LOB. Gram-positive cocci were isolated more frequently in EOB than in LOB (x ²=4.1,P=0.04). The risk of EOB was significantly increased by the presence of pulmonary contusion [relative risk (RR) 15.0; confidence interval (CI) 1.99-113.25], pneumonia before the onset of bacteremia (RR 3.56; CI 1.17-10.69), AIS score greater than 32 and an abdominal injury score greater than 9 (RR 3.11; CI 1.02-9.49), while intravascular catheters and mechanical ventilation did not represent risk factors for EOB. LOB had a very different pattern and their risk was significantly increased by exposure to intravascular catheters (RR 4.96; CI 1.23-19.94) and to mechanical ventilation lasting more than 7 days (RR 3.6; CI 1.6-8.1).Conclusions Scoring with the AIS of the abdominal and thoracic trauma at admission to the ICU appears a useful tool for identifying trauma patients at increased risk of EOB. A rigorous policy of catheter placement and maintenance as a means of reducing late bacteremias in trauma patients is essential.     

Attention during looking and reaching as assessed by heart rate in 7(1/2)-month-old infants

Attention mediates the acquisition and encoding of information about the world and is central to motor action. Heart rate deceleration and behavioral inhibition are sensitive indices of the attentional process, but it is unknown whether these indices are valid in the context of overt action. The current study investigated the relationship between visual attention, action, and heart rate during reaching in 7(1/2)-month-old infants. We found that infants showed prolonged looking and large heart rate decelerations on reaching and looking trials. We conclude that overt action itself does not prevent the autonomic and behavioral changes that are also seen in attention to simple visual displays and that attention is maintained throughout the act of reaching.     

双歧杆菌对早产儿食道pH值的影响及临床意义

目的为探讨双歧杆菌对早产儿食道pH值的影响，及其对早产儿易发生的消化道疾病的防治意义。方法我们采用便携式24hpH值自动记录仪，对61例早产儿进行了食道pH值的动态监测。结果口服双歧杆菌活菌制剂组的30例早产儿，食道pH值明显高于未服药的对照组，t=2．4093，P＜0．05。总pH值＜4的时间占总观察时间的百分比显著小于对照组。并且治疗组发生消化道疾患的人数也较对照组少。结论早产儿口服双歧杆菌活菌制剂可以减少胃食道反流等消化道疾病的发生。     

Breast development gives insights into breast disease

Aims : Studies of developing human breasts are essential for understanding the organogenesis as well as molecular pathogenesis of benign and malignant breast diseases. In this study we have examined the distribution of TGF-α, TGF-β1, tenascin-C and collagen type IV with the aim of starting to build a picture of the profile of molecules that may be involved in the development of the human breast.  

Methods and results

Ten fetal breasts (16 to 23 weeks of gestation) and 45 infant breasts, ranging in age from newborn to 2 years, were used in this study. Paraffin sections from these samples were immunostained with antibodies for these proteins and for Ki67 to elucidate the level of proliferative activity in different stages of breast development. TGF-α immunoreactivity was observed both in the stromal and the epithelial cells within fetal and infant breasts up to 25 days. TGF-β1 immunoreactivity was localized in the extracellular matrix. Tenascin-C was found around the neck of the developing breast bud and in the extracellular matrix of the infant with peaks in the newborn at 6–12 weeks. The immunoreactivity for type IV collagen was more intense in the region of the breast bud neck in the fetal breasts and reduced around the tips of lobular and terminal-end buds within the infant breasts.  

Conclusions

The distribution of the growth factors and extracellular matrix proteins within the developing human breast indicates that they play a significant role in different cellular compartments during morphogenesis and provides insights into breast disease.     

A selective inhibitor of thromboxane biosynthesis enhances immediate and inhibits late cutaneous allergic reactions in man

Thromboxanes may be involved in late cutaneous reactions (LCRs). A new selective inhibitor of thromboxane biosynthesis was studied for its effect on immediate skin test reactions (WFRs) and LCRs in nine adult nonatopic volunteers (open study) and eight adult atopic patients (double-blind study vs. placebo). WFRs and LCRs were elicited by intradermal injections of 25 micrograms of compound 48/80 and 200 IU of rabbit anti-human IgE antibodies, and the patients' receiving injections of 0.32, 1.6, 8, 40, and 200 IU of anti-IgE antibodies. Dazoxiben (100 mg orally three times once every 4 hr) increased the diameter of wheals (p less than 0.005 in volunteers; p less than 0.05 in six patients receiving no additional drug treatment), favored their dispersion (lymphangitis/pseudopodia), and caused systemic reactions (headache, chills) in at least two out of eight patients. Edema formation during LCRs was markedly depressed in 13 out of 16 persons. Flare diameter and erythemata during LCRs were not altered. These data suggest a role of thromboxanes and their natural antagonists (e.g., prostacyclin) in the regulation of allergic inflammatory processes.     

α2-Adrenergic receptor subtype alterations in the brainstem in the sudden infant death syndrome

Background: The sudden infant death syndrome (SIDS) is still the main cause of postneonatal infant death. However, the causes and mechanisms of SIDS have never been completely elucidated. Catecholamines, via α2-adrenergic receptor (α2-AR) interactions, are known to influence brainstem autonomic and respiratory activity. Aims: To examine the catecholaminergic system abnormalities in SIDS victims, we investigated the alterations of α2-AR subtypes. Subjects and methods: We examined the developmental changes of α2-AR subtypes in the brainstem, especially in cardiorespiratory nuclei, in 21 SIDS victims and 17 age-matched controls by means of immunohistochemical methods. For statistical analysis, the χ²-test or Fisher’s exact probability test was performed. Results: There was a significant decrease in α2A-AR immunoreactivity in the solitary nucleus and ventrolateral medulla (VLM) in the medulla oblongata in SIDS victims compared with in control cases, but there were no significant differences of the α2B and α2C-AR immunoreactivity in the brainstem between SIDS victims and controls. Conclusion: α2A-AR immunoreactivity was selectively decreased in the solitary nucleus and VLM in the medulla oblongata in SIDS victims, so there was no possibility that it was secondary to chronic hypoxia or repeated ischemia. It may be related to some impairment of the cardiorespiratory neuronal system. Therefore, SIDS victims may be vulnerable to asphyxia, hypoxia, and/or hypercapnia, and fail to exhibit brainstem responses.     

Travel vision in infant monkeys: Maturation rate and abnormal stereotyped behaviors

Three monkeys with travel vision and 5 controls were observed with their mothers during the first 6 months of age and then for another 3 months after they had been placed in social isolation. In the home cage, the experimental animals did not differ from controls except that two held a hand before their eyes in a stereotyped fashion not previously reported for animals. In an unfamiliar environment the blind animals did not look at an observer, threatened less than normal, and were awkward in moving around. Animals who held hands before eyes tended to approach a flickering visual stimulus.