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1.
The considerably lower vitamin E level found in cord blood and in newborns at birth than those found in the venous blood of mothers at delivery are not yet fully explained. In a group of 217 not selected newborns, we attempted to establish the relation between vitamin E and C levels at delivery and the changes during the first year of life. The mean serum vitamin E level rose from 0.37 mg/ml at 3 days to 0.80 mg/100 ml at 6 months and to 0.72 mg/100 ml at 12 months. On the other hand vitamin C mean levels lowered from 0.93 mg/100 ml in cord blood to 0.77 mg/100 ml at 6 months and to 0.73 mg/100 ml at 12 months. The rise of vitamin E values could be explained by the early use of infant solid foods with high vitamin and mineral content and by the increase of serum lipoproteins. Except at 3 days after delivery there were no individual values of serum vitamin E below the acceptable 0.35 mg/100 ml limit. However, serum vitamin C levels compatible with a moderate risk were very often observed, i.e., in 27.1% of infants at 6 months and in 30.5% at 1 year. Thus, vitamin E intake in infants was satisfactory with the usual diet but not vitamin C for which blood levels were not adequate. In view of these findings it appears necessary to evaluate periodically the vitamin E as well as vitamin C status in the infant population.  相似文献   

2.
Accommodative esotropia during the first year of life   总被引:1,自引:0,他引:1  
Two infants developed accommodative esotropia during their first six months of life. One infant, whose age at onset was 4 1/2 months, had 4.50 diopters of hyperopia. The second infant, whose age at onset was 5 months, had 3.50 diopters of hyperopia. In both infants, the eyes completely aligned with hyperopic correction. Two points are stressed. First, when the amount of hyperopia exceeds +3.00, consideration should be given to an accommodative element as the cause of the esotropia, even if the child is only 4 to 6 months old. Second, even with small angles of esotropia, an accommodative element should be considered, if there is a substantial amount of hyperopia.  相似文献   

3.
Systolic blood pressure was measured in 36 infants with median gestational age of 29 weeks (range 24-35 weeks) and birth weight of 1160 g (range 642-1500 g). Measurements were made at 1, 6 and 12 weeks, and subsequently at 12-weekly intervals during the first year of life. No infant developed chronic lung disease. Systolic blood pressure increased over the first 24 weeks (p < 0.001) to a mean value of 95 mmHg, but did not change significantly over the next 24 weeks. These data provide a reference range of blood pressure levels during the first year of life for infants born at an early gestational age.  相似文献   

4.
This study investigated the developmental changes in the mechanical properties of the respiratory system in growing horses. Pulmonary mechanics and lung volumes were serially measured in anesthetized foals during the first year of life. Quasi-static pressure-volume curves were generated, and functional residual capacity (FRC) was measured using a closed nitrogen equilibration technique. At birth, chest wall compliance normalized to body weight was substantially less than that reported in other less precocious newborn species, while lung compliance normalized to body weight was similar to values reported for other species. Characteristics of the transition from the neonatal to adult respiratory system in the foal included a decrease in the ratios of chest wall to lung compliance (Cw/CL) and the unstressed volume of the chest wall to TLC, and a constant FRC/TLC throughout most of the study period. The somatic growth of the foal and its respiratory system were uneven processes, with increases in lung volume lagging increases in overall body size.  相似文献   

5.
The C18 fatty acid fraction of 38 samples of mature human milk from Spanish women was analyzed using capillary gas chromatography. The average content of trans fatty acids found in these samples represented 0.95% of total fatty acids. This value is lower than the percentage found in human milk from other developed countries in which the consumption of hydrogenated fat is higher. Trans fatty acid content in human milk has been related to the types of fats and oils present in the diets of the nursing mothers. According to the results obtained in this survey, we can also conclude that the amount of trans forms in breast milk lipids is lower than the trans content found in infant formulas in Spain.  相似文献   

6.
BACKGROUND: The establishment of the nasopharyngeal flora was followed in Costa Rican children from birth to 1 year of age. METHODS: Nasopharyngeal cultures were obtained at 1 (n = 413), 3 (n = 393), 6 (n = 376) and 12 months (n = 356) of age from children representative of the population in the Puriscal district. Weekly cultures were obtained from a subcohort of these children (n = 101). Mother-infant diads (n = 95) and preschool children (n = 208) attending day-care centers were also studied. RESULTS: The estimated proportion of colonized children in the population differed markedly depending on the frequency of culture. Quarterly cultures showed a slow increase in carrier rates from 3.9% for Haemophilus influenzae, 3.1% for Streptococcus pneumoniae and 6.5% for Moraxella catarrhalis at 1 month of age to 10.1% carrying H. influenzae and 19.4% carrying S. pneumoniae by the end of the first year. By quarterly culture the proportion of children colonized at least once was 36% for S. pneumoniae, 26% for H. influenzae and 28% for M. catarrhalis. In contrast weekly sampling showed that 95 to 100% of the children were colonized at least once during the first year of life with H. influenzae, S. pneumoniae or M. catarrhalis. Nasopharyngeal carriage of H. influenzae, S. pneumoniae and M. catarrhalis was low in the mothers, and very few mother-infant pairs carried identical bacteria at the same time. In contrast carrier rates were high in the siblings attending day care (H. influenzae 27.9%, S. pneumoniae 39.4%, both organisms 26.6%). Infants with siblings had significantly higher bacterial carriage at all ages than infants without siblings. CONCLUSIONS: Quarterly nasopharyngeal cultures showed that Costa Rican infants acquire their nasopharyngeal flora at a rate comparable with that for infants in developed countries and that siblings are an important source of the bacteria. Weekly samplings showed that virtually all children were colonized at least once during the first year of life.  相似文献   

7.
The murine fatty acid transport protein (FATP) was identified on the basis of its ability to facilitate uptake of long chain fatty acids (LCFAs) when expressed in mammalian cells. To delineate FATP domains important for transport function, we cloned the human heart FATP ortholog. Comparison of the human, murine, and yeast amino acid sequences identified a highly conserved motif, IYTSGTTGXPK, also found in a number of proteins that form adenylated intermediates. We demonstrate that depletion of intracellular ATP dramatically reduces FATP-mediated LCFA uptake. Furthermore, wild-type FATP specifically binds [alpha-32P]azido-ATP. Introduction of a serine to alanine substitution (S250A) in the IYTSGTTGXPK motif produces an appropriately expressed and metabolized mutant FATP that demonstrates diminished LCFA transport function and decreased [alpha-32P]azido-ATP binding. These results are consistent with a mechanism of action for FATP involving ATP binding that is dependent on serine 250 of the IYTSGTTGXPK motif.  相似文献   

8.
OBJECTIVE: To study the effect of early postnatal dexamethasone (days 1-3) on the incidence and severity of chronic lung disease in preterm infants with respiratory distress syndrome. METHODS: A multicentre, randomised, placebo controlled, blinded study was carried out in 18 neonatal intensive care units in Israel. The primary outcome measure was survival to discharge without requirement for supplemental oxygen therapy beyond 28 days of life. The secondary outcome measures were requirement for mechanical ventilation at 3 and 7 days, duration of ventilation or oxygen therapy, need for subsequent steroids for established chronic lung disease and incidence of major morbidities. RESULTS: The study consisted of 248 infants (dexamethasone n = 132; placebo n = 116). No differences were found in the outcome variables except for a reduction in requirement for mechanical ventilation at age 3 days in treated infants (dexamethasone 44%, placebo 67%; P = 0.001). Gastrointestinal haemorrhage, hypertension, and hyperglycaemia were more common in treated infants, but no life threatening complications, such as gastrointestinal perforation, were encountered. CONCLUSIONS: These data do no support the routine use of early postnatal steroids, but may justify further study in a selected, high risk group of infants.  相似文献   

9.
Emotional reactivity is an important dimension thought to underlie individual differences in infant temperament. In a series of studies, we have examined the relation between behaviors reflecting this dimension and measures of heart rate variability. In the current study, longitudinal behavioral data on two groups of infants selected for their pattern of heart period variability are presented: those with high vagal tone (high heart rate variability) and those with low vagal tone (low heart rate variability) at 14 months of age. The data suggest that infants with high vagal tone were more reactive to both positive and negative events at 5 months and more sociable and approachful at 14 months. Infant reactivity to mildly stressful events seems to be a stable dimension during the first year, and there is a strong association between differences in reactivity and the degree to which the autonomic nervous system is influenced by vagal tone. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

10.
Symptomatic intracranial hemorrhage (ICH) in term infants is not common, but when it occurs it is usually secondary to trauma, coagulation disorders and/or hypoxia. The possibility of a structural cause for an infantile ICH is unfortunately not seriously considered until very late. In this paper we report the cases of five full-term infants, each of whom developed ICH secondary to a structural lesion during the 1st year of life. Three presented during the newborn period. A congenital saccular aneurysm of the middle cerebral artery in an 8-month old male infant; a posterior fossa arteriovenous malformation in a 2-week old female neonate; a deep parietal cavernous angioma in a 6.5-month-old male infant; a temporoparietal low-grade astrocytoma in a 12-day old male neonate and a temporoparietal desmoplastic ganglioglioma in a 9-day-old male neonate were the structural lesions that were causative for hemorrhage. In all cases but one, the diagnosis was reached by computerized tomography and/or magnetic resonance imaging. All infants underwent surgery for the removal of the hematoma and of the lesion causative for the bleed. All are alive at 19, 3, 11.5, 10, and 5 years, respectively. We discuss the diagnosis of ICH with special emphasis on contemporary imaging modalities and stress the benefits of aggressive and timely surgical treatment. We then consider a concise analysis of the world literature on the occurrence of structural causes of ICH during infancy.  相似文献   

11.
Candida is an increasing problem as a causal agent of nosocomial infection in neonates and infants. We report 15 cases of infective endocarditis caused by Candida spp treated at the Hospital Infantil de Mexico between 1980 and 1991. The diagnosis of endocarditis was established by the identification of Candida in at least two blood cultures and echocardiographic assessment. From 110 cases of systemic candidiasis during the eleven years period of study, fifteen patients presented endocarditis (13.6%), all had a central venous catheter. Three had antecedent of congenital heart disease. Candida isolation was obtained an average of 28 days after admission. The major clinical findings were: fever in 13 patients, respiratory distress and cardiac murmurs observed in nine respectively. Thrombocytopenia was present in eight children. The echocardiographic evaluation showed vegetations located in the superior vena cava in six, right atrium in five, tricuspid valve in two, inferior vena cava and right ventricle in one respectively. Three cases were subjected to surgical treatment. Nine patients died for a case fatality rate of 60%. The echocardiographic evaluation practiced in all patients with suspicion of systemic candidiasis is critical for the prognosis. The identification of endocardiac involvement coupled with the opportune administration of antifungal therapy and surgical treatment may improved the survival.  相似文献   

12.
Members of the synaptobrevin/VAMP family of v-SNAREs are thought to be essential for vesicle docking and exocytosis in both lower and higher eukaryotes. Here, we describe yeast mutants that appear to bypass the known v-SNARE requirement in secretion. Recessive mutations in either VBM1 or VBM2, which encode related ER-localized membrane proteins, allow yeast to grow normally and secrete in the absence of Snc v-SNAREs. These mutants show selective alterations in protein transport, resulting in the differential trafficking and secretion of certain protein cargo. Yet, processing of the vacuolar marker, carboxypeptidase Y, and the secreted protein, invertase, appear normal in these mutants indicating that general protein trafficking early in the pathway is unaffected. Interestingly, VBM1 and VBM2 are allelic to ELO3 and ELO2, two genes that have been shown recently to mediate the elongation of very long chain fatty acids and subsequent ceramide and inositol sphingolipid synthesis. Thus, the v-SNARE requirement in constitutive exocytosis is abrogated by mutations in early components of the secretory pathway that act at the level of lipid synthesis to affect the ability of secretory vesicles to sort and deliver protein cargo.  相似文献   

13.
Fatty acid-binding protein (FABP) is abundantly present in the cytoplasm of the cardiomyocyte, i.e. the cell which causes the contractile activity of the heart. Although FABP is thought to act as an intracellular long chain fatty acid (FA) carrier, definite experimental proof on this putative function has yet to be obtained. In the present study, experimental results from several authors were combined in an attempt to elucidate the precise physiological function of heart-type FABP in cardiac FA transport. It was calculated that, under normal conditions, the major part of FA in the cardiomyocyte is dissolved in lipid bilayers and that the presence of FABP in the heart enhances the aqueous solubility of FA more than 700-fold despite the fact that only a minor part (< 2%) of the total FABP content is then complexed with FA. Moreover, it is shown that, as a result of the enhanced cytoplasmic solubility, the FA flux from sarcolemma (the cellular membrane of the cardiomyocyte) to mitochondria is increased at least 17-fold in the presence of physiological amounts of FABP compared with the hypothetical situation in which FABP is absent. These calculations indicate the involvement of FABP in the transport of FA from the sarcolemma to those mitochondria lying in the innermost region of the cardiomyocyte. The extent to which FABP facilitates FA trafficking through the cytoplasm of the cardiomyocyte under physiological circumstances remains, however, to be established.  相似文献   

14.
The pseudocholinesterase levels and the nature of the enzyme as shown by the dibucaine number (D.N.) were estimated in 720 controls and 420 lepromatous leprosy patients, and 301 tuberculoid leprosy patients. There was no statistical difference in the esterase levels between leprosy patients and normal controls. But the distribution of D.N. was significantly different in the leprosy patients compared to the normal population studied. The D.N. below 40 indicates the samples with the atypical pseudocholinesterase--the presence of which is genetically determined. The distribution of samples with D.N. below 40 was significantly higher in the lepromatous leprosy patients compared to the normal population or tuberculoid leprosy patients. It is proposed that since there is a greater incidence of the atypical enzyme in lepromatous leprosy cases, the presence of this enzyme or the deficiency of the typical enzyme may make a person more susceptible to leprosy.  相似文献   

15.
An equimolar mixture of phosphatidylserine and (dioleoyl) phosphatidyl-ethanolamine could substitute for brain cephalin preparations in the single stage prothrombin assay. However, no clot promoting activity was observed on the addition of any of the individual long chain fatty acid-containing phospholipids. Short chain fatty acid-containing phospholipids, such as diheptanoylphosphatidylcholine, diheptanoylphosphatidylethanolamine, diheptanoylphosphatidic acid, and dihexanoylphosphatidylcholine, or dihexanoylphosphatidylethanolamine were inhibitory under all conditions studied. Similar effects of these two general classes of phospholipids were observed in a two-stage thrombin generation system, in which a mixture of bovine Factor Xa, Factor Va, and Ca2+ were interacted with prothrombin. In the presence of 25 mM Ca2+, dioleoylphosphatidic acid or brain phosphatidylserine alone, and with other long chain phospholipids, formed complexes with bovine plasma prothrombin. On the other hand, dioleoyl-, diheptanoyl- or dihexanoylphosphatidylcholine under comparable conditions showed no binding to prothrombin. There appeared to be a small degree of binding of diheptanoylphosphatidic acid to prothrombin, but it was insufficient to cause any significant change in apparent molecular weight of prothrombin. A mixture of prothrombin, Factor V, diheptanoylphosphatidic acid/diheptanoylphosphatidylcholine and Ca2+ eluted in the void volume of Sephadex G-200, but showed a much reduced coagulant activity. Though a net negative charge on the phospholipid surface is required for phospholipid-protein interactions, this does not necessarily promote coagulant activity. Bile acids and bile salts, such as cholic acid, deoxycholic acid, taurocholic acid, glycocholic acid, lithocholic acid and dehydrocholic acid, exerted varying levels of stimulation on the prothrombin assay and thrombin generation system, but were not as effective as the phospholipids. Interestingly, no interaction of these bile acids or salts with prothrombin was noted in the presence of Ca2+. The results of these experiments suggest that negatively charged micelles per se are not sufficient for binding alone and that other chemical and physical characteristics of phospholipids are of prime importance.  相似文献   

16.
OBJECTIVE: Fatty acid oxidation (FAO) disorders are frequently reported as the cause of sudden and unexpected death, but their postmortem recognition remains difficult. We have devised a biochemical protocol in which informative findings in liver tissue are microvesicular steatosis, elevated concentrations of C8-C16 fatty acids, glucose depletion, and low carnitine concentration. STUDY DESIGN: We analyzed 27 cases representing five FAO disorders and compared the results with those obtained in a retrospective blinded analysis of 418 cases of sudden infant death (313 SIDS, 45 infections, and 34 accidents and abuse). RESULTS: All cases of accidents and abuse correctly tested negative. Among the others, 25 (6%) showed at least two abnormal findings. Of these, 14 closely matched the biochemical profiles seen in specific FAO disorders. These included 2 cases with medium-chain acyl-CoA dehydrogenase deficiency, 4 cases consistent with glutaric acidemia type 2, 4 cases with either very long-chain acylcoenzyme A dehydrogenase deficiency or long-chain 3-hydroxy-acyl-coenzyme A dehydrogenase deficiency, and 4 cases predicted to be affected with carnitine uptake defect. CONCLUSION: The results of this study support the view that approximately 5% of all cases of sudden infant death are likely caused by an FAO disorder.  相似文献   

17.
Fatty acid binding protein (FABP) is a protein of 12,000 mol wt found in cytosol of intestinal mucosa and other tissues, which exhibits high affinity for long chain fatty acids. It has been suggested that FABP (which may comprise a group of closely related proteins of 12,000 mol wt) participates in cellular fatty acid transport and metabolism. Although earlier findings were consistent with this concept, the present studies were designed to examine its physiological function more directly. Everted jejunal sacs were incubated in mixed fatty acid-monoglyceride-bile acid micelles, in the presence or absence of equimolar concentrations of either of two compounds which inhibit oleate binding to FABP:flavaspidic acid-N-methyl-glucaminate and alpha-bromopalmitate. Oleate uptake, mucosal morphology, and oxidation of [14C]acetate remained unaffected by these agents, but oleate incorporation into triglyceride was inhibited by 62-64% after 4 min. The inhibition by flavaspidic acid was reversible with higher oleate concentrations. The effect of these compounds on enzymes of triglyceride biosynthesis was examined in intestinal microsomes. Neither flavaspidic acid nor alpha-bromopalmitate inhibited acyl CoA:monoglyceride acyl-transferase. Fatty acid:coenzyme A ligase activity was significantly enhanced in the presence of partially purified FABP, probably reflecting a physical effect on the fatty acid substrate or on the formation of the enzyme-substrate complex. Activity of the enzyme in the presence of 0.1 mM oleate was only modestly inhibited by equimolar flavaspidic acid and alpha-bromopalmitate, and this effect was blunted or prevented by FABP. We conclude that in everted gut sacs, inhibition of triglyceride synthesis by flavaspidic acid and alpha-bromopalmitate could not be explained as an effect on fatty acid uptake or on esterifying enzymes in the endoplasmic reticulum but rather can be interpreted as reflecting inhibition of fatty acid binding to FABP. These findings lend further support to the concept that FABP participates in cellular fatty acid transport and metabolism. It is also possible that FABP, by effecting an intracellular compartmentalization of fatty acids and acyl CoA, may play a broader role in cellular lipid metabolism.  相似文献   

18.
The objective of this study was to clarify the possible angiogenesis-promoting factors from human trophoblasts in early stage gestation. The existence of angiogenic growth factors such as basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF) in the condition medium from human villous trophoblasts was determined. Biological activity of angiogenic growth factors released by trophoblasts was examined using vascular endothelial cell lines. The condition medium from trophoblasts enhanced the growth of endothelial cells. Although cultured trophoblasts exhibited immunoreactive products for both bFGF and VEGF in the cytoplasm, only bFGF was detected in the condition medium by ELISA. The growth-enhancing activity of the condition medium was eliminated completely by the addition of anti-bFGF antibody but not with anti-VEGF antibody. Thus, trophoblastic cells seem to play an important role in extensive angiogenesis occurring in early gestation, mainly by releasing bFGF but not VEGF.  相似文献   

19.
OBJECTIVE: The aim of the study was to characterize n-3 and n-6 fatty acid delta5- and delta6-desaturase activities and their time course variations in human fetal liver between the 17th and 36th gestational week. STUDY DESIGN: Twenty-one biologic samples were obtained after legally approved medical abortion, according to French law. The desaturase activities were measured in the 21 liver samples by a radiochemical method by means of reverse-phase high-performance liquid chromatography. The fatty acid composition (percentage by weight) of liver phospholipids was assessed in 16 samples by gas-liquid chromatographic analysis. RESULTS: Both delta5- and delta6-desaturase activities were significantly expressed between the 17th and 36th gestational weeks. During the second trimester n-6 fatty acid delta5- and delta6-desaturase activities showed opposite patterns of variation; both then remained stable between the 25th and 36th weeks. Delta6-desaturation was higher in n-3 than n-6 fatty acids and peaked at the 18th gestational week. The percentages of linoleic and docosahexaenoic acids in liver microsomes were positively correlated with the gestation age (P < .01), whereas arachidonic acid remained stable. CONCLUSION: Significant n-3 and n-6 delta5- and delta6-desaturase activities are expressed in human fetal liver as early as the 17th gestational week and are stable throughout the third trimester. Their theoretic capacity evaluated from in vitro measurements appears lower than polyunsaturated fatty acid requirements and is not directly related to liver microsomal membrane fatty acid composition.  相似文献   

20.
The effects of polyunsaturated fatty acids (PUFA) on the structure of recombinant high density lipoprotein (rHDL) was investigated using homogeneous particles containing phosphatidylcholine (PC), [3H]cholesterol, and apolipoprotein A-I (apoA-I). The PC component of the rHDL contained sn -1 16:0 and sn -2 18:1 (POPC), 18:2 (PLPC), 20:4 (PAPC), 20:5 n-3 (PEPC), or 22:6 n-3 (PDPC). The concentration of guanidine HCl (D1/2) required to denature one-half of the apoA-I on rHDL containing long chain PUFA was reduced (1.57-1.70 m) compared to those containing POPC (2.83 m). Intrinsic apoA-I tryptophan fluorescence emission intensity and lifetimes were decreased for rHDL containing long chain PUFA compared to POPC and PLPC rHDL. Monoclonal antibody binding studies demonstrated that apoA-I had decreased immunoreactivity with monoclonal antibodies spanning amino acid residues 115-147 in rHDL containing long chain PUFA. PC lipid fluidity, measured as diphenylhexatriene (DPH) fluorescence polarization, was increased in PUFA rHDL compared to POPC rHDL. There also was a strong correlation between the number of sn -2 double bonds in rHDL and DPH fluorescence lifetime (r 2 = 0. 89). LCAT reactivity of the homogeneous size rHDL was ordered POPC = PLPC>PAPC> PEPC>PDPC. We conclude that rHDL with long chain PUFA in the sn -2 position of PC contain apoA-I that is less stable and in a different conformation than that in POPC rHDL and have a fatty acyl region that is more fluid and hydrated. The weaker interaction of apoA-I with PC containing PUFA may lead to hypercatabolism of apoA-I in plasma explaining, in part, the decreased plasma HDL and apoA-I concentrations seen with PUFA diets.  相似文献   

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