Search PubMed⌕ Search

Biomedical subjects

K Lee

Publications and source records attributed to K Lee.

At least 811 records · Page 45Linked to original sources
PubMed1987

Effects of different methods and severity of growing period feed restriction on growth and laying performance of white Leghorns.

Two experiments were conducted to study the effects of different methods of feed restriction and severity of feed restriction during the growing period on pullet growth and laying performance of White Leghorns. In Experiment 1, ad libitum feeding of the low protein diet (supplemented with amino acids) was the only treatment among four feed restriction treatments that did not significantly (P greater than .05) influence growing period feed consumption and body weight gain. The smallest body weight gain was obtained among birds subjected to the daily restrictive feeding (DRF) treatment. Ad libitum feeding of the low energy diet resulted in a significantly (P less than .05) poorer growing period feed efficiency than any other treatment. Both energy and protein utilization efficiencies for body weight gain were significantly (P less than .05) hindered by the skip feeding treatment. Although DRF birds consistently had higher egg production from 36 to 76 weeks of age than birds in any other group, overall average percent hen-day egg production from 20 to 76 weeks of age was not significantly (P greater than .05) improved by the DRF treatment. Also, in Experiment 2, various levels of DRF during the growing period did not significantly (P greater than .05) improve average percent hen-day egg production. Laying house mortality, feed efficiency, and egg weight were not significantly (P greater than .05) different among treatments (Experiments 1 and 2). Results of these experiments indicate that DRF was the most effective method of controlling growth rate and that neither method of feed restriction nor severity of feed restriction during the growing period significantly (P greater than .05) improved laying performance.

Animals↗
PubMed1987

Differential effects of hypoxia on the turnover of norepinephrine and epinephrine in the heart, adrenal gland, submaxillary gland and stomach.

The authors examined the effects of hypoxia (8% O2 in N2) on the turnover rates of norepinephrine (NE) and epinephrine (E) in the heart, adrenal gland, submaxillary gland and stomach. The turnover rates were estimated by measuring the decrease in the content of NE and E after an i.p. injection of alpha-methyl-p-tyrosine (250 mg/kg), an inhibitor of tyrosine hydroxylase. After a 4-h exposure to hypoxia, the turnover rate of NE in the heart and those of NE and E in the adrenal gland were increased, whereas that of NE in the submaxillary gland was decreased. The turnover rate of NE in the stomach was unchanged. Pretreatment with hexamethonium, a ganglionic nicotinic receptor blocker, abolished the hypoxia-induced changes in the turnover rate of NE or E in the heart, adrenal gland and submaxillary gland. Furthermore, transection of the spinal cord at the level of C5-6 abolished hypoxia-induced alterations in the turnover rate of NE and E in the adrenal gland and submaxillary gland. In contrast, the hypoxia-induced changes seen in the heart persisted, although at a lower level, even after transection. These results show that the effects of hypoxia on the activities of the sympathoadrenal system differ depending on the organs; activities are increased in the heart and adrenal gland, decreased in the submaxillary gland and unchanged in the stomach. Furthermore, the present data suggest that hypoxia-induced alterations in the activities of cardiac sympathetic nerves originate in both the brain and spinal cord, including preganglionic neurons, whereas changes in the activities of the sympathetic nerves to the adrenal gland and submaxillary gland originate mainly in the brain.

Adrenal Glands↗
PubMed1987

The effect of dietary protein on glomerular filtration rate in normal subjects.

The acute effect of the ingestion of 90 g of protein as meat and as milk protein (Casilan) on glomerular filtration rate (assessed by creatinine clearance) was examined in healthy subjects. The creatinine clearance increased 1.5 hours after the ingestion of meat and remained elevated for a further 2.5 hours. The mean maximal increase in creatinine clearance was 18 ml/min. Casilan on the other hand did not produce a significant increase in the creatinine clearance. When 6 subjects ingested 90 g of protein as Casilan daily for 5 days, the creatinine clearance increased after a delay of 3 to 4 days. When the same subjects increased their meat protein intake by 90 g as meat daily for 5 days, the creatinine clearance increased from the first day (by 23 ml/min) and remained elevated throughout the 5 days of study. We conclude that the effect of protein on glomerular filtration rate depends on the type of protein.

Adult↗
PubMed1986

Induction therapy in head and neck cancer. A comparison of two regimens.

Seventy-two patients with advanced resectable head and cancer received two courses of induction chemotherapy before definitive therapy. Forty-six patients were treated with platinol, Oncovin (vincristine), and bleomycin. Twenty-six received Platinol (cisplatin), Velban (vinblastine), and 5-fluorouracil (5-FU). Although both regimens had an overall response rate of 80% or more, the bleomycin-containing regimen had a higher complete response rate and better long-term disease control, with greater than 60% probability of remaining disease-free (36 month minimum follow-up). As given in this regimen, the 5-FU regimen was well tolerated but had a higher incidence of stomatitis and a low rate of complete responses. When the two regimens were compared to a historical control, the regimen with Platinol, Oncovin, and bleomycin was significantly better.

Adult↗
PubMed1986

Distribution of 'non-specific' cholinesterase-containing neurons in the dorsal thalamus of the rat.

This report describes the distribution of histochemically identified 'non-specific' cholinesterase (ChE)-containing neurons in the dorsal thalamus of the rat. Juvenile or young adult Long-Evans or Sprague-Dawley rats were sacrificed by formalin perfusion. Some animals received systemic injections of 1.5-2.0 mg/kg DFP 4-24 h prior to sacrifice. Separate series of 50 micron frozen sections were processed for cholinesterase histochemistry using acetylthiocholine, butyrylthiocholine, or propionylthiocholine as substrates. Adjacent sections processed with each of the 3 substrates allowed comparison of the distributions of neurons containing the histochemical reaction products. Neurons containing moderate to high concentrations of ChE reaction product were found in 3 distinct regions of the dorsal thalamus. First, neurons staining intensely for ChE were found in a cluster that corresponds to the thalamic reuniens nucleus. Second, a cluster of neurons staining intensely for ChE was found in a region that included the lateral part of the central lateral nucleus and extended laterally into the ventral-lateral part of the lateral dorsal nucleus. Third, moderate ChE staining was observed in the neurons of the anterior dorsal nucleus. Of these regions, only the anterior dorsal nucleus shows moderate to high levels of acetylcholinesterase. The function of ChE in normal brain function is unknown. It is particularly interesting, however, that the thalamic nuclei containing ChE-positive neurons send thalamocortical projections to the medial limbic cortex, including cingulate, retrosplenial and subicular cortices.

Acetylcholinesterase↗
PubMed1986

Malignant myoepithelioma of the breast. An immunohistochemical study by light and electron microscopy.

Myoepitheliomas of the breast are extremely rare; only four cases have been reported to date. It is not clear whether these tumors behave in a benign or malignant fashion, and no metastatic spread has been documented. We report a myoepithelioma of the breast with metastatic spread to an axillary lymph node. Myoepithelial cell (MEC) differentiation in the tumor was characterized using electron microscopic (EM) criteria. Immunologic investigations at the LM and EM levels showed that the tumor cells were positive for S100 protein, actin, and epidermal cytokeratin; these findings are indicative of MEC differentiation. By immuno-EM, cytokeratin filaments were present in a perinuclear location, while actin filaments were concentrated along the cell periphery. To the authors' knowledge, this is the first report of a breast myoepithelioma that has metastasized and also the first report of the immunologic characterization of a myoepithelioma at the light and electron microscopic levels.

Aged↗
PubMed1986

Variation in the temporal expression of overlapping baculovirus transcripts.

To investigate gene expression from the Autographa californica nuclear polyhydrolysis virus genome (AcNPV), complementary DNA (cDNA) was synthesized from polyadenylated RNA transcribed at 2 h and 10 h postinfection (p.i.) and then cloned into Escherichia coli using plasmid pUC-9. Eighteen 2 h cDNA plasmids were homologous to five distinct regions of the viral genome, while forty-nine 10 h cDNA plasmids were homologous to 15 regions including the five regions transcribed at 2 h. Temporal expression of polyadenylated RNA transcribed from diverse regions of the genome was examined using Northern blot hybridization with the above 2 and 10 h cDNA probes. All regions displayed overlapping sets of RNAs. In addition to HindIII-I/EcoRI-F (IF) and HindIII-B2/EcoRI-H (B2H), several, but not all, regions showed a sequential appearance of higher molecular weight RNAs as the infection progressed. Each overlapping set of RNAs exhibited unique characteristics including variations in the number of overlapping transcripts, their temporal regulation, and their relative abundance during the course of infection.

Animals↗
PubMed1986

Nitrate, nitrite balance, and de novo synthesis of nitrate in humans consuming cured meats.

Nitrate balance was measured in nine men consuming a fixed daily diet with constant nitrate (570 mumol/day), varying nitrite (18 to 150 mumol/day), and varying erythorbate levels. Nitrite and erythorbate were added to meat that was then cured and frozen until consumption. All diets were consumed by each subject for 17 days each. Average daily urinary nitrate excretion ranged from 959 to 2382 mumol/day. Subjects excreted significantly more nitrate in urine when fed nitrite cured meats with or without erythorbate than when fed uncured meat (1617 and 1577 versus 1430 mumol nitrate/day, respectively). The amount of nitrate excreted in urine consistently exceeded intakes of nitrate and nitrite by an average 870 mumol/day. This excess represented endogenous synthesis by subjects and was not due to unmeasured nitrate in the diet. The commonly used Greiss and xylenol procedures were unable to measure all nitrate in urine and in diets when compared to high performance liquid chromatographic analyses. The Greiss and xylenol analyses underestimated nitrate synthesis by 220 and 150 mumol/day, respectively when results were not adjusted by determining recovery of added nitrate.

Adult↗
PubMed1986

Prophylactic treatment with valproic acid or diazepam in children with febrile convulsions.

The purpose of this study was to limit prophylactic treatment of children with febrile convulsions to patients who have the highest risk of recurrence. Two hundred and thirty-one children with a first febrile seizure were divided into high- and low-risk groups according to estimated risk of recurrence. All high-risk children were offered treatment with valproic acid. If this was declined they were offered treatment with diazepam instead. Low-risk children were untreated. Valproic acid and diazepam were found to be equally effective in reducing the risk of recurrence of febrile convulsions. By selecting for prophylactic treatment according to estimated risk of recurrence it is possible to reduce the rate of recurrence of febrile seizures in children at high-risk (60%) to the same level as that of untreated low-risk children (23%). Only about half of all children with febrile convulsions need treatment and follow-up according to these criteria.

Child↗
PubMed1986

Myocarditis with myocardial infarction like findings in a 3-year old girl.

A 3 year-old Japanese girl had an acute onset associated with vomiting. The electrocardiogram (ECG) indicated changes similar to those of acute myocardial infarction (MI); there was no past history of kawasaki disease. Selective coronary angiography taken on the 28th day of illness revealed no abnormality. Thallium 201 scintigraphy was also performed and it revealed that the area of absent myocardial uptake was in the anterior wall. In serological findings, antibody titers against Coxsackie B-3 virus had risen significantly; therefore acute myocarditis caused by Coxsackie B-3 virus infection was diagnosed.

Antibodies, Viral↗
PubMed1986

The effects of cinepazide on the content, biosynthesis and turnover of noradrenaline, dopamine and 5-hydroxytryptamine in the rat brain under room air and hypoxia.

The effects of cinepazide, a vasodilator, on the content, biosynthesis and turnover of noradrenaline (NA), dopamine (DA) and 5-hydroxytryptamine (5-HT) in the rat brain were examined under room air and hypoxia (10% O2, 90% N2). Under room air, cinepazide had no significant effects on the content of NA, DA, 5-HT and 5-hydroxyindoleacetic acid (5-HIAA), the accumulation of 3,4-dihydroxyphenylalanine (DOPA) and 5-hydroxytryptophan (5-HTP) after central decarboxylase inhibition, and the depletion of NA, DA and 5-HT after synthesis inhibition. After 2 hr-exposure to hypoxia, the content of NA, 5-HT and 5-HIAA was decreased, whereas the content of DA was unchanged. The accumulation of DOPA and 5-HTP was decreased. The depletion of DA and 5-HT was inhibited by hypoxia, whereas the depletion of NA was unaffected. Under hypoxic conditions, cinepazide had no effects on the content of NA, DA and 5-HT, the accumulation of DOPA and 5-HTP, and the depletion of NA and DA, whereas cinepazide increased both the rate of 5-HT depletion and the content of 5-HIAA. The present data suggest that cinepazide selectively stimulates the functional activities of 5-HT neurons in the brain, which are depressed by hypoxia.

5-Hydroxytryptophan↗