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Query: UMLS:C0038187 (starvation)
 24,951 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Patients with advanced cancer and cachexia typically demonstrate modestly increased rates of energy expenditure in the presence of diminished food intake due to anorexia and to gastrointestinal disturbances. Rates of glucose production by the liver, gluconeogenesis and glycolysis to lactate (Cori cycle) are increased, fat mobilisation and oxidation are accelerated. There is a redistribution of body proteins away from muscle towards visceral proteins, resulting in marked muscle protein loss. Cancer cachexia differs from simple starvation and demonstrates metabolic similarities to sepsis or polytrauma. The metabolic response in the patient with cancer is largely due to mediators released by the tumour or by the host; recently the role of cytokines such as tumour necrosis factor alpha (TNF alpha), interleukin-1 (IL-1) and -6 (IL-6) and interferon gamma (INF gamma) has been emphasized. Catabolic hormones such as glucocorticoids and adrenaline have also been implicated. Cytokines have the potential to reproduce experimentally the clinical syndrome of cancer cachexia. There is evidence of increased production of several of them in certain types of cancer. There are overlapping activities of the cytokines TNF alpha, IL-1, IFN gamma and IL-6. The contribution of each of them to cancer cachexia remains unclear. Inhibition of cytokine activity using specific antibodies in cancer-bearing experimental animals demonstrated partial prevention of cachexia. A positive feedback between macrophage-derived IL-1 and tumour-derived IL-6 has been demonstrated recently in experimental cancer cachexia. Cytokines may support tumour growth by acting as growth factors.
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PMID:Pathophysiology of cancer cachexia. 815 43

Cancer cachexia is among the most dramatic situations of depletion in body energy reserves. To ascertain whether the pattern of body composition alteration during tumour development is influenced by aging as in uncomplicated starvation, we compared the difference of body composition between Yoshida sarcoma bearing rats and young (200 g, 7 weeks) and adult (400 g, 13 weeks) control rats. After the same duration of tumour bearing, mass and composition of tumours were similar in adult and young rats, indicating that they are independent of host age. Food intake decreased to a remarkably similar value in both young and adults. Body water content was elevated in hosts of both ages. The relative deficit of body lipid vs controls was similar for both, the absolute lipid deficit being therefore larger in adult than in young tumour-bearing rats (14.3 +/- 4.4 g vs 6.8 +/- 0.9 g; P < 0.01). In contrast, there was a relatively larger deficit of body protein in young rats. Paradoxically, these rats still maintained a positive nitrogen balance whereas this balance was negative in adult tumour-bearing rats. In conclusion, as previously shown in uncomplicated undernutrition, the anorexia induced by Yoshida sarcoma development is still associated with some protein accretion in young rats whereas cachexia develops in adults.
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PMID:Body protein and lipid deficit in tumour-bearing rats in relation to age. 821 4

Starvation or dietary restriction are known to modify post-fasting dietary self-selection. We have examined the effects of activation of the serotoninergic system and food deprivation on macronutrient self-selection following a period of starvation. Rats were starved for 4 days and either treated or not with dl-fenfluramine or fluoxetine. Starved untreated animals showed a post-fasting anorexia and an increased preference for carbohydrate intake, even though lipids remained the preferred source of calories. Treatment with fenfluramine or fluoxetine increased post-fasting anorexia, abolished the preference for carbohydrates and decreased lipid intake. Fluoxetine, but not fenfluramine, resulted in decreased protein intake as well. Following a 2-day refeeding period ad libitum, during which the animals were not treated with drugs, the anorectic effect of fenfluramine disappeared but that of fluoxetine remained unchanged. In addition, we noted that at an equimolar dose to dl-fenfluramine (100 mumol/kg/day) fluoxetine treatment resulted in the death of all the animals in the group by the second day of refeeding; no deaths were observed in any of the other groups. In conclusion, we confirm a post-starvation anorexia and increased carbohydrate intake following long-term fasting. In addition we show that activation of the serotoninergic system abolishes the increase in carbohydrate intake and potentiates post-starving anorexia.
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PMID:Effect of activation of the serotoninergic system during prolonged starvation on subsequent caloric intake and macronutrient selection in the Zucker rat. 850 69

Many factors can modify nutritional status in cancer patients, including cachexia, nausea and vomiting, decreased caloric intake or oncologic treatments capable of determining malabsorption. Cachexia is a complex disease characterized not only by a poor intake of nutrients or starvation, but also by metabolic derangement. Nausea and vomiting may limit the nutrient intake and are most often the consequences of oncologic treatments or opioid chronic therapy. Decreased caloric intake is considered to be one of the major causes of malnutrition, although the causes of anorexia remain unclear. Malabsorption is generally attributed to the consequences of oncologic treatments reducing the gastrointestinal absorption. Biochemical measurements and immunological tests may be not reliable indicators of nutritional status in cancer patients. Therefore, medical history, physical examination, estimates of daily oral intake, weight changes and an appropriate consideration of the nutritional requirements according to the stage of disease must still be assessed. The therapeutic approaches should be individualized and realistic. Whenever possible, oral nutrition is the method of choice, with due consideration for specific dietary needs. Nausea and anorexia can be reduced by different kinds of drugs. A careful decision based on good clinical judgement is necessary before deciding to start either enteral or parenteral nutrition, to avoid a useless, costly and difficult treatment. In choosing the route for administration of nutrients, availability of and access to a functioning gastrointestinal tract, compliance and comfort of the patient, gastrointestinal toxicity due to chemotherapy or radiotherapy fields, different costs, duration and place of treatment should be considered rather than the different capacity of parenteral versus enteral nutrition. However, postoperative periods after massive intestinal resection often require prolonged parenteral nutrition. The benefits of parenteral nutrition are not often demonstrable in patients with bowel obstruction. Different ethical aspects are presented. Flexibility in attempting to meet the nutrition needs of each patient is probably the most useful guide.
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PMID:Nutrition in cancer patients. 877 Dec 86

As a complex syndrome, cachexia has different clinical manifestations; anorexia appears to be one of the most frequent findings, together with weight loss. Anorexia is the cause and partly the consequence of metabolic changes and of progressive undernourishment. In cancer cachexia, weight loss is associated with a marked decrease of food intake and severe alteration of body composition. Malnourished cancer patients show a marked loss of adipose tissue and protein mass with BIA evidence of decreased body cell mass and expansion of extracellular water. The mechanisms of anorexia and cachexia are still a matter of debate, but the possible involvement of cytokines in the pathogenesis of this syndrome has opened up new possibilities for its understanding and treatment. As a result of the multifactorial etiology of cancer cachexia/anorexia, therapies that stimulate appetite and promote greater food intake, coupled with factors that influence metabolism and cytokine production may be an optimal therapeutic strategy. Of particular interest appears to be the possible role played by fish oil in antagonizing the negative effects of cytokines. Future research in this field will help clinicians develop new methods to treat patients who have disease-induced starvation and wasting.
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PMID:Food intake and body composition in cancer cachexia. 885 Feb 14

Anorexia nervosa is associated with multiple endocrine abnormalities. Hypothalamic neuropeptides and monoamines are involved in the regulation of human appetite, and they are changed in several ways in anorexia nervosa. But it remains to be clarified whether these alterations are secondary or etiologic. Feeding behaviour in anorexia nervosa is characterised by a strong ambivalence and not by loss of appetite. Hypothalamic amenorrhea is a diagnostic criterion, and is not only secondary as it often precedes the weight loss and persists for a long time after weight and motor activity have returned to normal. Hypersecretion of corticotropin releasing hormone seems to be secondary to starvation, but at the same time it may keep up and intensify the anorexia, physical hyperactivity and amenorrhea. Low production of insulinlike growth factor-I and high growth hormone secretion reflects the nutritional deprivation. In conclusion most of the neuroendocrine abnormalities are secondary to weight loss, but some of them seem to participate in a circulus vitiosus and maintain the emaciated state.
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PMID:[Neuroendocrine disorders in anorexia nervosa--primary or secondary?]. 899 10

Progressive wasting is common in many types of cancer and is one of the most important factors leading to the early death of cancer patients. Although anorexia frequently accompanies cachexia it has been difficult to establish a simple cause-and-effect relationship, and nutritional supplementation is not able to effectively reverse the process of cachexia. An increased resting energy expenditure may contribute to weight loss in some cancer patients and may explain the increased oxidation of fat. Futile energy-consuming cycles, such as the Cori cycle, may contribute to the increased energy demand. Unlike starvation, weight loss in cancer arises equally from loss of muscle and fat, and the process is characterized by an increased catabolism of skeletal muscle and a decrease in protein synthesis. Several experimental studies have suggested a role for the cytokines tumor necrosis factor alpha, interleukins-1 and -6, and interferon gamma as mediators of the process of cachexia, although conclusive data supporting a role in human disease are often lacking. Catabolic factors capable of direct breakdown of muscle and adipose tissue appear to be secreted by cachexia-inducing human tumors and may play an active role in the process of tissue degeneration. Pharmacologic intervention using antagonists to cachexia factors may be capable of reversing the wasting process.
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PMID:Cancer cachexia: metabolic alterations and clinical manifestations. 905 39

Several studies have addressed the question of the effects of starvation on immune function and changes in lymphocyte subsets. Patients with anorexia nervosa are severely malnourished, but there have been few studies of immune parameters in this group. For this reason, phenotypic markers of T cell function and activation were studied in 20 severely underweight patients with anorexia nervosa and again after a period of refeeding. The most significant finding was a reduction in the percentage and absolute number of CD8+ T cells in patients with anorexia, the result of a marked reduction in memory (CD45RO+RA-) CD8 cells. A tendency for recovery in numbers of this subset was seen after refeeding. A decreased memory:maive cell ratio was also seen among CD4 cells, but was less marked. Subtle abnormalities in activated CD4 and CD8 cells were also found in the patient group at the initial sampling, but did not follow any clear pattern. These findings indicate that starvation in anorexic patients is accompanied by a large change in memory CD8 T cells. It may be speculated that this relates to the perceived lack of symptomatic common viral infections in underweight anorexic patients and their return with the recovery of weight.
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PMID:T lymphocyte subpopulations in anorexia nervosa and refeeding. 932 79

The effect of starvation-related malnutrition on muscle performance and on the energy cost of exercise remains unknown, as does the timing of improvement by refeeding. Indeed, in most diseases that induce malnutrition, muscle dysfunction is worsened by an inflammatory process. Thus, physical performance and the energy cost of exercise were studied in 15 semistarvated malnourished anorexia nervosa (AN) patients during exercise on an ergometric bicycle (3-min steps of 30 W) before and after 8, 30, and 45 d of refeeding. Results were compared with those of 15 normal-weight healthy subjects matched for age, sex, and physical activity. Before refeeding, the workload reached during the exercise was 49% lower in AN patients than in control subjects (P < 0.01). It was correlated with body weight, fat-free mass, and leg muscle circumference (P < 0.002). The performance improved dramatically during refeeding (P < 0.03), reaching normal values after 45 d of refeeding, despite fat-free mass and leg muscle circumference values that were still 20% lower in AN patients than in control subjects (P < 0.01). At this time, the exercise-related VO2 remained unchanged, being approximately 25% lower than that of the control subjects when corrected for muscle mass differences (P < 0.03). In conclusion, in AN patients muscle performance was restored by refeeding long before the patients achieved normal nutritional status. The economic cost of physical activity for these malnourished patients allows them to maintain a relatively high level of physical activity. This relative overactivity has two goals in AN: it reinforces anorexia and contributes to the excess of energy expenditure needed for weight loss.
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PMID:Refeeding improves muscle performance without normalization of muscle mass and oxygen consumption in anorexia nervosa patients. 917 82

Clinicians working with contemporary women with anorexia nervosa have commented on the ascetic component in anorexia, meaning their self-denial, heightened morality, opposition between body and spirit, asexuality, and denial of bodily death (Mogul, 1980; Palazzoli, 1978; Rampling, 1985; Sabom, 1985; Turner, 1984). While these clinicians have commented on the asceticism in contemporary anorexia nervosa, they have little to say about the role of culture in subjective experiences of this asceticism. As we have seen, Jane and Margaret used notions of asceticism about food and the body that are a part of their religious beliefs to create a personal meaning system through which they expressed their self-starvation. These cases, while supporting clinical studies that point to an ascetic component in modern anorexia, go further to suggest that in some cases, this asceticism may be encoded in religion. Religious anorectics like Jane and Margaret challenge models of anorexia nervosa that understand the condition exclusively in terms of cultural foci on "dieting" and secular ideals of beauty and bodily thinness for women (Bemporad, Hoffman, & Herzog, 1989; Chernin, 1985; Garner et al., 1980; Orbach, 1986; Rost, Newhaus, & Florian, 1982). They also suggest a continuing persistence into the twentieth century of an association between religiosity and self-starvation noted by historians during the early Christian, medieval, and late-Victorian periods in the West (Bell, 1985; Brown, 1988; Brumberg, 1985, 1988; Bynum, 1987). The above discussion points to the new directions in psychological anthropology which challenge a strict and opposing dichotomy between the conscious and unconscious, between culture (seen as "public") and the individual mind (seen as "private" and idiosyncratic). Obeyesekere's concept of "the work of culture," (Obeyesekere, 1990) and Stephen's concept of the "autonomous imagination" are especially useful in understanding how persons like Jane and Margaret use in imaginative ways cultural symbols, such as notions of asceticism about food and the body that are a part of religion, to give meaning to their personal concerns with growth, separation, and sexuality. We saw how Jane and Margaret transform cultural symbols and language to express their starvation and deep anxieties. These cases lend support to views that culture and religion, as symbolic systems, have underpinnings in deep motivation (Obeyesekere, 1981, 1990; Spiro, 1965, 1987). They also suggest that the relations between culture and the individual mind (and between culture and "illness," between "normal" and "abnormal") must be viewed as a moving continuum, with culture constantly worked and reworked by the individual imagination in innovative and creative ways.
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PMID:The imaginative use of religious symbols in subjective experiences of anorexia nervosa. 921 86


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