Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0029713 (immaturity)
 4,335 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The clinical response and changes in water and salt homeostasis during ORT was studied in 15 infants less than 2 months old (range 2-50 days) with acute diarrhoea. Eight patients were neonates and 7 were 1-2 months old. The oral rehydration solution contained 60 mmol sodium per litre. All patients except one were successfully rehydrated. The fluid retention was significantly higher in neonates and young infants than in infants above 3 months of age treated in the same way. One patient in the group of neonates who had a normal sodium level on admission developed hypernatremia with a sodium level of 162 mmol/l 36 hours after the start of ORT. The urinary sodium excretion was lower in the neonates than in the young infants. The results show that neonates and young infants have a lower capacity than older infants to excrete water and salt and therefore run a great risk of developing fluid and salt retention during ORT. The risk is most pronounced in neonates who, due to immaturity of the renal function, are unable to excrete excess fluid and salt.
 ...
PMID:Oral rehydration therapy in neonates and young infants with infectious diarrhoea. 330 Jan 47

Human sperm immaturity was tested by nuclear chromatin decondensation (NCD) in 1% sodium dodecylsulphate (SDS) of spermatozoa used in 74 consecutive IVF treatments. NCD was significantly higher in the presence of 2 mmol/l dithiothreitol (DTT) and after washing sperm from semen with 6 mmol/l ethylenediaminetetraacetic acid (EDTA). NCD was significantly less in insemination suspensions prepared by the swim-up technique than in the original semen. NCD with DTT was inversely correlated with sperm motility and motility index but there were no significant relationships between NCD and other semen analysis variables. There was no significant correlation between any NCD test and the proportion of oocytes fertilised in vitro. The only factors being significantly correlated with the fertilisation rate were proportion of sperm with normal morphology (Kendall correlation, tau = 0.36, P less than 0.001) and sperm concentration (tau = 0.14, P less than 0.05). Logistic regression analysis of fertilisation rates showed that only percentage normal sperm morphology was significant. It is concluded that NCD does not provide additional useful clinical information about sperm fertilising ability in vitro.
 ...
PMID:Spermatozoal nuclear chromatin decondensation in vitro: a test for sperm immaturity. Comparison with results of human in vitro fertilisation. 345 Mar 77

The capability of the developing intestinal circulation to maintain a vasoconstrictor response during postganglionic adrenergic nerve stimulation or norepinephrine infusion was examined in 34 swine aged 6 h to 2 mo anesthetized with pentobarbital sodium. Aortic and portal venous pressures, electrocardiogram (ECG), and blood flow (F) through the superior mesenteric artery were recorded, and intestinal vascular resistance (MVR) was calculated as mean pressure difference per mean F. Baroreceptor reflex inhibition by bilateral occlusion of the carotid arteries increased MVR, section of the splanchnic nerve and postganglionic fibers decreased MVR, and short-latency F decreases were obtained during mesenteric nerve stimulation (MNS). Latencies for the decreases in F shortened with age and with increasing MNS frequency (5-17 Hz) at any age. Prolonging MNS for 60 s at 10 or 12 Hz led to sustained high MVR in 6-h to 7-day-old animals; however, MVR decreased toward control before the end of the 60-s MNS period in animals 1 to 2 mo old. Intra-arterial infusion of norepinephrine (0.5 microgram X kg-1 X min-1) decreased F and increased MVR in all animals; but by 5 min of infusion, F was returning toward control level in all but the youngest. This demonstration that the least mature intestinal circulation was least capable of autoregulatory escape from vasoconstriction provides further evidence of its functional immaturity.
 ...
PMID:Autoregulatory escape from vasoconstriction of intestinal circulation in developing swine. 381 6

Taurinuria is characteristic of the immature rat. The excessive taurine loss could be the result of brush border or basal lateral membrane immaturity. The beta-amino acid, taurine, and D-glucose were examined using isolated brush border membrane vesicles (BBMV), slices and tubules prepared from 28-day-old rats. In BBMV, taurine accumulation was inversely proportional to osmolarity, indicating uptake rather than binding, and taurine accumulation was Na+-dependent. BBMV from 28-day rats did not accumulate D-glucose to the same degree as in adult BBMV, and the initial rate of uptake was slower. Taurine uptake had a similar Km and Vmax in BBMV from immature rats. Despite similarities in the kinetics of taurine uptake, higher urinary taurine concentrations are found in younger rats. The efflux of taurine from slices and tubules was much slower than in adults and probably accounts for the taurinuria of young animals. A diet low in methionine and taurine (LTD) given for seven days resulted in a lower excretion and fractional excretion of taurine than in animals fed a normal sulfur amino acid diet (NTD). A high-taurine diet (HTD) causes excessive taurinuria. These patterns of excretion are reflected at the brush border membrane surface with greater uptake after the LTD and reduced uptake after the HTD. A kinetic analysis of adult and 28-day-old animal BBMV reveals that the Vmax of accumulation is altered by diet, whereas the Km remains unchanged. The Vmax is higher in BBMV from LTD animals and lower in BBMV from HTD animals.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Divergent membrane maturation in rat kidney: exposure by dietary taurine manipulation. 403 Feb 27

Three hours after the administration of sodium nucleinate the activation of glycolysis, the hexosomonophosphate shunt, the urea cycle (determined by the analysis of key enzymes), the expression of FC gamma-receptors and the decrease of oxidizing phosphorylation were noted in the peritoneal macrophages of mice. By 36 hours the gradual decrease of these characteristics occurred. After three oral administrations of the preparation immature macrophages with lower metabolic activity and increased oxidizing phosphorylation appeared in the exudate, while resident and activated cells practically disappeared. The immaturity of the cells was confirmed by their incubation in vitro. The changes in the cells, revealed in this investigation, are supposed to occur due to the redistribution of activated and intact macrophage populations in situ.
 ...
PMID:[Redistribution and activation of peritoneal macrophages with the peroral use of sodium nucleinate]. 406 Sep 53

Seven tension pneumothoraces developed in six very low birthweight infants receiving assisted ventilation for hyaline membrane disease. Mean values for blood pressure and creatinine clearance (Ccr) tended to increase following pneumothorax decompression, although neither increase was statistically significant. Urine volume, osmolar clearance and urine sodium excretion all increased significantly in the 8 h following diagnosis and decompression of pneumothoraces. However, when expressed as a percentage of Ccr, none of these variables changed significantly. Mean sodium balance changed from positive to negative despite a significant increase in urine aldosterone excretion. It is suggested that the increases in osmolar clearance and sodium excretion were consequences of the increase in Ccr following pneumothorax decompression. Developmental immaturity in the renal tubular response to aldosterone might also have contributed to development of negative sodium balance.
 ...
PMID:Diuresis and natriuresis following acute pneumothorax in very low birthweight infants. 409 68

A new model of renal cystic disease was developed in newborn Syrian hamsters by the repeated injection of 9-fluoroprednisolone acetate (9-FPA), a long-acting adrenal corticosteroid. Kidneys harvested from the tenth to the fourteenth day of age showed diffuse cystic dilatation of nearly all cortical convoluted tubules. Microdissection revealed that cystic changes primarily involved proximal convoluted tubules and, to a lesser degree, the distal tubules. Electron microscopy showed immaturity of development and varying degrees of degeneration of the cells of the proximal convoluted tubule. Intraluminal obstruction was not detected and therefore could not account for the cystic changes. Analysis of electrolytes in serum and selected tissues showed a significant reduction in potassium and sodium of serum, and significant depletion of potassium, magnesium and calcium in the skeletal muscle. Thus, there was no direct relationship between an electrolyte deficiency and the cystic changes.
 ...
PMID:Adrenal corticosteroid-induced renal cystic disease in the newborn hamster. 472 95

Studies on the correlation between hyperosmolality and brain damage, especially intracranial hemorrhage, were carried out on young and newborn rabbits following infusion with 7% sodium bicarbonate. 1) All the young rabbits injected with 7% sodium bicarbonate died of hyperosmolality at over 380 mOsm/L (the mean was 462 mOsm/L) after drip infusion at the rate of 20-60 ml/kg/hr. Young rabbits under a 10% hypoxic environment died even at the 350 mOsm/L level (the mean was 392 mOsm/L) during infusion of 7% sodium bicarbonate. Half of the case of newborn rabbits injected with 7% sodium bicarbonate at 10 ml/kg, intraperitoneally, had intracranial hemorrhage at 335 mOsm/L. When the hyperosmolality reached 392 mOsm/L (50 ml/kg), intracranial hemorrhage was observed in all cases. 2) The main cause of death in young and newborn rabbits was subdural hemorrhage in the subtentorial region. Intraventricular hemorrhage was observed in about 40% of the cases of young and newborn rabbits. 3) The blood pH was elevated by the drip infusion, but when the hyperosmolality reached about 400 mOsm/L, the blood pH began to fall. At the same osmolality, pCO2 showed a marked elevation. It is likely that the decrease of the blood pH was caused by the elevation of pCO2 and the outflow of H+ from intracellular compartments resulting from the hyperosmolality. These results apparently indicate that fatal intracranial hemorrhage was induced by hyperosmolality and was enhanced by the combination of hypoxia and immaturity.
 ...
PMID:Intracranial hemorrhage following administration of sodium bicarbonate in rabbits. 626 52

Shortly after birth, a 1,860-g premature male newborn with respiratory distress syndrome had brisk diuresis, rapid weight loss, and severe hyponatremia despite aggressive Na+ and fluid replacement. The serum cortisol level was normal, and the 17-OH progesterone concentration was low. He did not show any response to treatment with dexamethasone and desoxycorticosterone acetate. Results of renal function studies were within the normal range for his gestational age. The serum aldosterone level and plasma renin activity were grossly elevated, confirming the diagnosis of pseudohypoaldosteronism. This uniquely early and dramatic presentation was attributed to immaturity of the proximal renal tubule at 32 weeks' gestation. The subsequent improvement paralleled the rapid maturation of the kidney after birth.
 ...
PMID:Pseudohypoaldosteronism. 634 58

Isolated renal cortical tubule fragments from rats ranging in age from less than 48 h to 15 weeks were used to examine the pattern of cystine uptake with development. Immature tubules took up cystine with a faster initial rate than mature tubules and did not reach a steady state by 60 min. By eight weeks of age, the timed uptake of cystine began to approach a steady state and between 8 and 11 weeks the uptake pattern achieved its adult form of reaching a steady state by 30 min of incubation. Analysis of the intracellular metabolism of the cystine taken up by the newborn tubules revealed that the majority had been reduced to cysteine with the formation of small amounts of reduced glutathione. Cystine entered the renal cortical tubule cell from the newborn via two saturable transport systems similar to the mature animal. The kinetic parameters of initial uptake of these two transport systems were similar in the mature and newborn animal except for a higher maximum transport velocity for the low Km, low capacity system in the newborn. Lysine inhibited cystine uptake by newborn tubules and this inhibition appeared to occur on the low Km, low capacity transport system similar to the adult. Cystine uptake was sodium dependent with an apparent affinity for sodium of 36 mequiv./l. From this data, the physiologic cystinuria of the immature animal does not appear to be refeable to a lower rate of influx as previously observed with the cortical slice. Other mechanisms should be sought to explain this phenomenon of immaturity.
 ...
PMID:Developmental pattern of cystine transport in isolated rat renal tubules. 681 31


<< Previous 1 2 3 4 5 6 7 Next >>