Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0038187 (starvation)
 24,951 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The cytotoxic potential of heterologous rabbit antibody directed against mouse serum albumin (MSA) and alpha-fetoprotein (AFP) was investigated in vitro with a cell line (Hepa) derived from the mouse hepatoma BW7756. Anti-AFP in the presence of complement could kill Hepa cells at concentrations of anti-MSA that were virtually nontoxic. The specificity of the anti-AFP was defined by demonstrating that Hepa cell toxicity was dependent upon and paralleled the secretion of AFP in synchronized cultures. Furthermore, neither antiserum could be shown to be significantly toxic to mouse neuroblastoma cells (Neuro-2A). Immunoglobulin purified from pools of antisera was also highly effective in producing cytotoxicity even in a complement-free system. This reaction proceeded more slowly, requiring nearly 48 hr to reach maximum effect in comparison to the 12 hr for complement-mediated toxicity. MSA and AFP are secreted during different phases of the cell cycle. In cultures arrested by isoleucine starvation, labeled AFP appears in the medium 10 hr after release of the blockade in association with S phase. The appearance of labeled MSA is delayed until the first mitosis. Cytotoxic effects of anti-AFP parallel the secretion of AFP in synchronous cultures. Both antisera could be inhibitory to the secretion and synthesis of the proteins of their antigenic specificity. MSA synthesis was more susceptible to this inhibition than was AFP synthesis. The significance of this phenomenon and its association with the differential cytotoxicity of the antiserum are discussed.
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PMID:The influence of antisera specific for alpha-fetoprotein and mouse serum albumin on the viability and protein synthesis of cultured mouse hepatoma cells. 6 16

In order to compare, in vitro, the TSH suppressive effects of iodothyronines, rat pituitary quarters were first preincubated with T4, T3, rT3, or 3,3'-diiodothyronine (T2) in Gey and Gey buffer containing 1% bovine serum albumin for 2 h at 37 C and then incubated at 37 C for 1 h with the iodothyronine under study and TRH. TSH released into the medium during incubation was compared to that released by control pituitary fragments, which were not exposed to iodothyronines. All four iodothyronines (T3, T4, rT3, and T2) were able to significantly inhibit the TRH-induced release of TSH from pituitary fragments in a dose range of 0.015-2.2 microgram/ml. However, much larger doses of sodium iodide (1.25 mg/ml) and diiodotyrosine (10 and 30 microgram/ml) had no significant effect on the release of TSH. Among T3, rT3, and T4, T3 was the most potent and rT3 was the least potent. The relative potency of T3:T4:rT3 appeared to be approximately 100:12:1 when estimated from the lowest doses that caused significant inhibition of TRH-induced release of TSH, and approximately 100:6:0.5 when estimated from the doses that caused 50% inhibition of TSH release; the TSH inhibiting potency of T2 was similar to that of rT3. The activity of T4 could not be explained entirely on the basis of contamination of T4 with T3 or by in vitro conversion of T4 to T3. Similarly, the available data suggested that rT3 and T2 possess some, albeit modest, intrinsic TSH-Suppressive activity. TSH-inhibiting activities of T3, T4, and rT3 were also studied using pituitary fragments from starved and iodine-deficient rats. There was no evidence of a change in the sensitivity of the thyrotroph to either T3 or T4 in starvation. Similarly, comparison of the responses to several doses of rT3 did not indicate any significant abnormality in the sensitivity of the thyrotroph to rT3 in starvation or iodine deficiency. However, comparison of the TSH-suppressive effects of T4 in the iodine-deficient and normal rat indicated a significant increase in the sensitivity of the thyrotroph to T4 in iodine deficiency. A similar trend was also evident in the effect of T3 in iodine deficiency, but it fell short of statistical significance.
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PMID:Comparison of inhibitory effects of 3,5,3'-triiodothyronine (T3), thyroxine (T4), 3,3,',5'-triiodothyronine (rT3), and 3,3'-diiodothyronine (T2) on thyrotropin-releasing hormone-induced release of thyrotropin in the rat in vitro. 10 90

This study illustrates the specific immune response of chronically starved, undernourished adults after inoculation of live smallpox vaccine. It produced no adverse effect, and major vaccinial reaction was observed in all. 63% of undernourished individuals showed a fourfold or greater rise of the neutralizing antibody titre. In contrast, only 9% of normal healthy subjects could show similar response. However, the prevaccination titre was much lower in the undernourished group than in the control group, and the postvaccination titre also remained persistently lower in the former than in the latter group. Furthermore, whereas the specific humoral antibody response in the undernourished subjects was partially adequate, the development of specific cellular immunity against vaccinia was remarkably poor, indicating that smallpox vaccination in these subjects might be less effective against variola infection. This observed profound effect of chronic starvation and severe undernutrition on the immune apparatus was possibly multifactorial, protein depletion being the most important factor, as proved by the significantly low serum albumin level. The significantly low peripheral blood lymphocyte count and spectacular unresponsiveness to many antigens in these individuals suggested profound depression of the thymolymphatic system. Further, the significantly low level of neutralizing antibody in the malnourished subjects suggested that the formation of this protective antibody might necessitate the cooperation of T lymphocytes.
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PMID:Undernutrition and immunity: smallpox vaccination in chronically starved, undernourished subjects and its immunologic evaluation. 19 73

Normal female rats were given 15mug of ethynyloestradiol/kg body wt. for 14 days and were killed on day 15 after starvation for 12-14h. The livers were isolated and were perfused with a medium containing washed bovine erythrocytes, bovine serum albumin, glucose and [1-(14)C]oleic acid; 414mumol of oleate were infused/h during a 3h experimental period. The output of bile and the flow of perfusate/g of liver were decreased in livers from animals pretreated with ethynyloestradiol, whereas the liver weight was increased slightly. The rates of uptake and of utilization of [1-(14)C]oleate were measured when the concentration of unesterified fatty acid in the perfusate plasma was constant. The uptake of unesterified fatty acid was unaffected by pretreatment of the animal with oestrogen; however, the rate of incorporation of [1-(14)C]oleate into hepatic and perfusate triacylglycerol was stimulated, whereas the rate of conversion into ketone bodies was impaired by treatment of the rat with ethynyloestradiol. Pretreatment of the rat with ethynyloestradiol increased the output of very-low-density lipoprotein triacylglycerol, cholesterol, phospholipid and protein. The production of (14)CO(2) and the incorporation of radioactivity into phospholipid, cholesteryl ester and diacylglycerol was unaffected by treatment with the steroid. The net output of glucose by livers from oestrogen-treated rats was impaired despite the apparent increased quantities of glycogen in the liver. The overall effect of pretreatment with oestrogen on hepatic metabolism of fatty acids is the channeling of [1-(14)C]oleate into synthesis and increased output of triacylglycerol as a moiety of the very-low-density lipoprotein, whereas ketogenesis is decreased. The effect of ethynyloestradiol on the liver is apparently independent of the nutritional state of the animal from which the liver was obtained. It is pertinent that hepatocytes prepared from livers of fed rats that had been treated with ethynyloestradiol produced fewer ketone bodies and secreted more triacylglycerol than did hepatocytes prepared from control animals. In these respects, the effects of the steroid were similar in livers from fed or starved (12-14h) rats. Oestrogens may possibly inhibit hepatic oxidation of fatty acid, making more fatty acid available for the synthesis of triacylglycerol, or may stimulate the biosynthesis of triacylglycerol, or may be active on both metabolic pathways.
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PMID:Effects of ethynyloestradiol on the metabolism of [1-14C]oleate by perfused livers and hepatocytes from female rats. 22 70

The daily flux of amino acids in the body is extensive. Protein synthesis is estimated to be 300 g daily in an adult man. This requires uptake and release of 150 g essential amino acids, yet the dietary requirement for essential amino acids in only 6 g. This indicates extensive and efficient recycling of essential amino acids released by protein breakdown. The catabolism of essential amino acids by the liver is sensitively regulated in relation to requirements. A study of availability of tryptophan to rats receiving various levels of tryptophan in the diet shows that plasma tryptophan increases only when intake exceeds requirements and at these higher levels of intake tryptophan oxygenase activity in the liver becomes increased shortly after meals. In addition, the carbohydrate content of the diet causes tryptophan to become deposited in the free amino acid pool of muscle through an insulin-dependent mechanism. Dietary carbohydrate also effects plasma tryptophan due to a fall in the plasma level of non-esterified fatty acids which compete with tryptophan for binding sites on serum albumin. Consequently, after carbohydrate the proportion of plasma tryptophan bound to serum albumin increases, so that there is less nonbound tryptophan in the plasma. The metabolic significance of this has yet to be demonstrated. Finally, protein metabolism in skeletal muscle exhibits considerable efficiency of reutilization of essential amino acids, since the main products passing into the blood are alanine and glutamine. It has been shown that 3-methylhistidine present in muscle protein in not reutilized for synthesis of protein and that its excretion in the urine can provide a useful index of muscle catabolism. In prolonged starvation of adults or protein deficiency in children, output of 3-methylhistidine is much reduced, suggesting an adaptive reduction in muscle protein catabolism. It is emphasized that, because of its function in monitoring dietary amino acid intake, liver protein metabolism responds rapidly to changes in protein intake and in consequence protein deficiency causes early depletion, whereas muscle protein undergoes depletion later and is subject to adaptive processes that restrict the loss.
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PMID:Regulation of protein metabolism in relation to adequacy of intake. 81 Apr 22

Based on data indicating that decreases in body weight (BW), arm muscle circumference (AMC), and rapid-turnover proteins (RTPs) correlate with fatal septic complications after surgery for esophageal cancer, we examined possible factors contributing to protein-calorie malnutrition (PCM) in patients with this disease. Eight parameters of nutritional status were assessed. Associations between sex, age, stage of cancer, and degree of dysphagia and PCM were analyzed via multiple linear regression for 75 patients with esophageal cancer and 58 with gastric cancer. These four factors independently contributed to PCM in patients with esophageal cancer, whereas malignant tumor and age contributed to PCM in those with gastric cancer. The degree of dysphagia was related to decreases in serum albumin and RTP and weakly related to decreases in BW and AMC. Stage of cancer, age, and sex were associated with reductions in albumin and/or RTP. Thus, we conclude that simple starvation, malignant tumor, age, and sex contribute to PCM and probably to the occurrence of fatal septic complications postoperatively.
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PMID:Factors related to malnutrition in patients with esophageal cancer. 180 92

Protein and electrolyte disturbances in hepatic and muscle tissues are related to trauma, sepsis, or short term starvation or semistarvation. The consequences of a prolonged semistarvation are poorly understood. For five weeks, male adult rats were offered 50% of the diet until they had a weight loss of 40%, after which protein and electrolyte (Ca++, Mg++, Zn++, Na+, K+) changes in the liver and soleus and extensorum digitorum longus muscles were analyzed. There was a significant weight loss after 5 weeks of semistarvation. Hepatic protein and serum albumin were not changed, but the authors observed a significant muscle protein depletion. A fall in Zn++ levels in the blood was accompanied by a rise in muscle and liver concentrations. The rise in Ca++ and Mg++ concentration in blood and in the muscles might be related to the enhanced proteolysis. Results suggest that the early changes of protein and electrolyte metabolism at tissue level with semistarvation impair muscular and hepatic functions as they delay adequate response to trauma and infection.
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PMID:[Effects of food restriction on the protein and electrolyte composition in the liver and muscles of rats]. 188 80

The effects of modified protein sparing therapy (PSP) and total parenteral nutrition (TPN) on total and wound metabolism were studied for 96 hours after laparotomy and a small gastric excision in 40 rabbits starved for seven days. A further eight starved and eight non-starved animals served as controls for the blood variables. Normal healing up to day 14 was studied in 20 non-starved animals. The difference in deaths and animals in poor condition, 42.1 per cent in PSP and 18.6 per cent in TPN, respectively, was clear but statistically non-significant. PSP led to a lower mean serum albumin concentration than TPN, 25.7 +/- 3.7 (SD) and 28.7 +/- 3.0 (p = 0.02), respectively. The animals receiving PSP excreted significantly more 3-methylhistidine. TPN maintained a positive nitrogen balance, but PSP produced a negative one. The collagen content of the skin scar was lower after PSP (3.1 +/- 0.7 mg) than after TPN (4.5 +/- 1.3 mg) (p less than 0.05), the latter coming close to the level for normal 4-day healing, 4.5 +/- 1.2 mg. Prolyl 4-hydroxylase (PPH) activity showed no difference. No inter-group differences in collagen were found in the stomach. Both regimens totally reversed the starvation-induced decrease in PPH activity in the stomach, but only partially in skin. Thus TPN produced better total and skin wound metabolism after laparotomy and starvation than did PSP. No differences in visceral wound healing were observed.
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PMID:Effect of intravenous feeding on wound healing in starvation: an experimental study on the rabbit. 193 25

The effect of epidermal growth factor (EGF) and insulin on DNA, RNA, and cytoskeletal protein labeling in primary rat astroglial cell cultures was investigated. Cultures were grown for 15-30 days in vitro in 10% fetal calf serum (FCS)-supplemented medium and then maintained in serum-free basal medium (DMEM) supplemented with fatty acid-free bovine serum albumin (BSA) for a starvation period of 24 hr before the addition of factors. The effect of factors was tested at different times (4, 10, 22, and 28 hr). At each time, [methyl-3H]thymidine or [5,6-3H]uridine was added to the control and treated cells; the incubation time after the addition of labeled precursors was 2 hr at 37 degrees C. The results obtained indicated that the addition of EGF or FCS significantly stimulated [methyl-3H]thymidine incorporation into DNA, reaching the maximum effect after 22 hr. EGF alone significantly stimulated [3H]uridine incorporation into RNA, and this effect was already maximum at 4 hr and remained constant up to 22 hr. The addition of insulin alone caused a slight increase in nucleic acid labeling for short times (4-10 hr). In contrast with EGF, no detectable stimulation of incorporation of labeled precursors after insulin treatment for 22 hr was observed. On the other hand, the addition of insulin in the presence of EGF induced an increase of the values observed with EGF alone on macromolecular synthesis at all the times studied. Furthermore, a decrease in cell number was observed in confluent cultures maintained for 1 week in medium containing DMEM + BSA in comparison to serum-supplemented (DMEM + BSA + FCS) cultures.
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PMID:Effect of epidermal growth factor and insulin on DNA, RNA, and cytoskeletal protein labeling in primary rat astroglial cell cultures. 245 91

A highly differentiated porcine skin organ culture model has been developed for future investigations of membrane-coating granules (MCG) and their role in epidermal differentiation. In contrast to many previous systems, cultures do not undergo necrosis of the upper epidermis or display dermo-epidermal separation, but survive for at least 3 weeks, at which time mitotic cells are still evident. Although rete projections are gradually smoothed out and the viable epidermis thins at a rate of approximately 0.35 cells per day, the stratum corneum gains approximately 1.5 corneocytes per day. Furthermore, at 3 weeks all the major differentiation markers are expressed, including keratohyalin granules, MCG, and an orthokeratotic stratum corneum. The system is inexpensive, simple to establish, and does not require elevated oxygen levels. The main requirements are 1) the use of Dulbecco's minimal essential medium supplemented with 2) hydrocortisone (100 micrograms/ml), 3) growth at an air/liquid interface, and 4) attached connective tissue. The further addition of vitamin C (300 micrograms/ml) and/or bovine serum albumin (2 mg/ml) offered no obvious advantage. Degeneration of organ cultures in standard cell culture media was discovered to be caused by fetal bovine serum (FBS). FBS-induced degeneration was not prevented by adding any of the supplements tested, or the inclusion of 3T3 fibroblasts, even when culturing at an air/liquid interface. Complete submersion rapidly killed specimens, presumably through oxygen starvation. The ability to maintain a fully keratinizing system for several weeks, in a totally chemically defined medium, will prove valuable for research not only into the role(s) of MCG in epidermal biology but also studies of desquamation and epidermal differentiation.
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PMID:A fully differentiating epidermal model with extended viability: development and partial characterization. 258 41


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