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91.
Branched chain amino acids—What are they good for? 总被引:4,自引:0,他引:4
From the above consideration it is apparent that the BCAA fulfill unique physiological functions in normal man. Thus, the BCAA constitute a principal source of nitrogen repletion in muscle tissue after the ingestion of a protein meal. In addition, the BCAA and leucine in particular have been implicated in the regulation of synthesis as well as breakdown of muscle protein. However, much remains to be learned regarding the physiological significance of the BCAA in normal and pathological states. Theoretical considerations and several preliminary studies have suggested a therapeutic role of the BCAA in certain clinical disorders although, in the case of liver coma, the present evidence does not support such a role, The possible clinical usefulness of BCAA after trauma and infection still remain to be clarified and the papers by Freund , Hartig , and Schmitz in this issue of Clinical Nutrition are welcome contributions to this important and rapidly developing area of research. 相似文献
92.
A small dose of isoprenaline or saline was administered intraperitoneally to rats 20 min before the administration of one of the amino acids l-dopa or l-tryptophan. Isoprenaline caused a marked increase in the brain concentration of the administered amino acid. Isoprenaline has previously been shown to cause a decrease in at least some of those plasma amino acids which compete with l-dopa and tryptophan for carrier-mediated transport into the brain. The effect of isoprenaline on the concentrations of dopa and tryptophan in the brain is suggested to be at least partly caused by a change in the relationship between endogeneous and administered amino acids. It is also possible that a direct effect of isoprenaline on the blood-brain barrier transport system contributes to the effect.The reported finding might be of clinical interest in view of the therapeutic importance of aromatic amino acids with a central site of action. 相似文献
93.
Ohrvall U Eriksson B Juhlin C Karacagil S Rastad J Hellman P Akerström G 《World journal of surgery》2000,24(11):1402-1408
With adequate medical management the midgut carcinoid tumor generally is an indolent malignancy associated with substantial
life expectancy and appreciable life quality, even in the presence of liver metastases and significant tumor burden. Abdominal
complications may occur in this entity of carcinoids owing to entrapment of intestines and encasement of mesenteric vessels
by mesenteric metastases and associated marked mesenteric fibrosis. This may be the cause of abdominal pain, disabling diarrhea,
weight loss to the extent of malnutrition, and eventually the risk of death with acute or chronic intestinal obstruction or
intestinal gangrene. Operative removal of the mesentericointestinal lesion is often indicated to prevent or treat these complications
but may be technically difficult when mesenteric metastases extend in the vicinity of major vessels in the mesenteric root.
At laparotomy 56 patients with advanced midgut carcinoids underwent removal of the mesenteric tumor with a method for preserving
the mesenteric vessels. This was feasible by mobilizing and releasing the right colon and mesenteric root from posterior adhesions,
identifying the mesenteric artery below the pancreas, and free-dissecting this artery on the tumor capsule in the mobilized
mesentery. Dissection was successful even with tumors initially judged inoperable unless tumor growth completely surrounded
the mesenteric vessels or extended retroperitoneally. One patient was subjected to distal intestinal artery bypass. Symptom
relief was been substantial and often of long duration after mesenteric tumor removal in patients who prior to surgery often
had threatening intestinal ischemia. Patients with advanced midgut carcinoids may benefit markedly from dissectional removal
of mesenteric tumors, which (conceivably better than conventional wedge resection) preserves the length of the remaining intestine. 相似文献
94.
Absorption/metabolism of sulforaphane and quercetin, and regulation of phase II enzymes, in human jejunum in vivo. 总被引:2,自引:0,他引:2
Niclas Petri Christer Tannergren Birgit Holst Fred A Mellon Yongping Bao Geoff W Plumb Jim Bacon Karen A O'Leary Paul A Kroon Lars Knutson Patrik Forsell Thomas Eriksson Hans Lennernas Gary Williamson 《Drug metabolism and disposition》2003,31(6):805-813
For the first time the human intestinal effective permeability, estimated from the luminal disappearance and intestinal metabolism of phytochemicals, sulforaphane and quercetin-3,4'-glucoside, as well as the simultaneous changes in gene expression in vivo in enterocytes, has been studied in the human jejunum in vivo (Loc-I-Gut). Both compounds as components of an onion and broccoli extract could readily permeate the enterocytes in the perfused jejunal segment. At the physiologically relevant, dietary concentration tested, the average effective jejunal permeability (Peff) and percentage absorbed (+/- S.D.) were 18.7 +/- 12.6 x 10-4 cm/s and 74 +/- 29% for sulforaphane and 8.9 +/- 7.1 x 10-4 cm/s and 60 +/- 31% for quercetin-3,4'-diglucoside, respectively. Furthermore, a proportion of each compound was conjugated and excreted back into the lumen as sulforaphane-glutathione and quercetin-3'-glucuronide. The capacity of the isolated segment to deconjugate quercetin from quercetin-3,4'-diglucoside during the perfusion was much higher than the beta-glucosidase activity of the preperfusion jejunal contents, indicating that the majority (79-100%) of the beta-glucosidase capacity derives from the enterocytes in situ. Simultaneously, we determined short-term changes in gene expression in exfoliated enterocytes, which showed 2.0 +/- 0.4-fold induction of glutathione transferase A1 (GSTA1) mRNA (p < 0.002) and 2.4 +/- 1.2-fold induction of UDP-glucuronosyl transferase 1A1 (UGT1A1) mRNA (p < 0.02). The changes in gene expression were also seen in differentiated Caco-2 cells, where sulforaphane was responsible for induction of GSTA1 and quercetin for induction of UGT1A1. These results show that food components have the potential to modify drug metabolism in the human enterocyte in vivo very rapidly. 相似文献
95.
JC VANCE DC CHANT DI TUDEHOPE PH GRAY AJ HAYES 《Journal of paediatrics and child health》1997,33(6):504-508
Objectives: To describe the physical growth patterns of infants born to narcotic dependent mothers (INDM) over a 12 months period and, if possible, to relate the growth to drug taking patterns during pregnancy.
Methodology: The growth of a cohort of 43 INDM was measured during the first 12 months of life. Weight and length measurements were compared with percentile charts and converted to Z scores. Questionnaire data about drug taking practices, demographic variables and the neonatal period (including withdrawal scores) were obtained.
Results: Twenty-four (55.8%) of INDM had evidence of neonatal drug withdrawal requiring treatment with phenobarbitone. At birth, Z scores for weight and length indicated relative intrauterine growth retardation. By 12 months, there had been some catch up growth, but Z scores for weight and length were still below zero. Persistent weight retardation at 12 months was correlated with methadone dosage during pregnancy, but not the need for phenobarbitone therapy.
Conclusions: The growth patterns of INDM in the first 12 months of life indicated that at birth there was evidence of intrauterine growth retardation, but by 12 months the growth was little different from the rest of the community. There appears to be some influence of narcotic agents taken while pregnant on subsequent growth of INDM. 相似文献
Methodology: The growth of a cohort of 43 INDM was measured during the first 12 months of life. Weight and length measurements were compared with percentile charts and converted to Z scores. Questionnaire data about drug taking practices, demographic variables and the neonatal period (including withdrawal scores) were obtained.
Results: Twenty-four (55.8%) of INDM had evidence of neonatal drug withdrawal requiring treatment with phenobarbitone. At birth, Z scores for weight and length indicated relative intrauterine growth retardation. By 12 months, there had been some catch up growth, but Z scores for weight and length were still below zero. Persistent weight retardation at 12 months was correlated with methadone dosage during pregnancy, but not the need for phenobarbitone therapy.
Conclusions: The growth patterns of INDM in the first 12 months of life indicated that at birth there was evidence of intrauterine growth retardation, but by 12 months the growth was little different from the rest of the community. There appears to be some influence of narcotic agents taken while pregnant on subsequent growth of INDM. 相似文献
96.
JC Labarthe 《Archives of disease in childhood》1997,77(2):140-144
This study was designed to look at the differences in visuospatial abilities between boys and girls before they can speak fluently. At the mandatory two year follow up visit, children were given the opportunity to build a tower and a bridge. In children whose birth weight was > or = 2500 g, the capacity for erecting a tower was the same in both sexes, but for building a bridge striking differences were noted according to their sex. Among the 376 children of this category, 41 out of 199 boys (21%) were able to build a bridge in comparison with 15 out of 177 girls (8%). This difference is highly significant. In children whose birth weight was < or = 2500 g, no differences were noted either for building a tower or a bridge. By showing that boys outnumber girls among the most skilled toddlers in spatial abilities, this work confirmed the action of a male related factor on cerebral lateralisation. 相似文献
97.
Background: Neuroendocrine tumors usually present with inoperable metastatic disease and severe hormonal symtoms. Specific chemotherapy, alpha-interferon and the somatostatin analog octreotide are established therapies in these patients but all of them eventually fail. Other somatostatin analogs, e.g., RC-160 and lanreotide, are currently being studied in different doses and modes of administration.Patients and methods: Nineteen patients with advanced neuroendocrine gastrointestinal tumors [13 carcinoids and six endocrine pancreatic tumors (EPT)], liver metastases being present in 18, most of them heavily pretreated, were included. Seventeen out of 18 patients had somatostatin receptors demonstrated by octreotide scintigraphy. Lanreotide was given as four daily subcutaneous injections, starting with 750 µg/d, then increasing every week up to 12,000 µg/d after six weeks, a dose which was maintained, if tolerated, for 12 months, or until progression.Results: There was a significant tumor size response (>50%) in one patient (5%), whereas 12 patients (70%) had tumor stabilization for 12 months. Bichemical tumor markers were significantly reduced at six months (urinary 5-hydroxyindoleacetic acid and plasma chromogranin) and 12 months (chromogranin) and the overall biochemical response rate was 58% with this high dose of lanreotide. Adverse events were observed and four patients stopped the treatment due to adverse events. Studies of tumor biopsies before and during treatment indicated induction of apoptosis in patients with tumor stabilization and biochemical response.Conclusion: High-dose treatment with lanreotide (12,000 µg/d) produced tumor size response in 5%, stabilization in 70% and a biochemical response in 58% of patients. These results should be related to the advanced stage of the disease as indicated by the mean duration of disease of more than four years, but they do not appear to be better than those achieved with standard doses of somatostatin analogs. However, in responding patients we observed induction of apoptosis in the tumors, a phenomenon not seen with regular doses of somatostatin analogs, but often produced by chemotherapeutic agents. 相似文献
98.
P de Lonlay-Debeney JC Fournet D Martin F Poggi C Dionisi Vicci M Spada G Touati J Rahier F Brunelle C Junien JJ Robert C Nihoul-Fékété JM Saudubray 《Archives de pédiatrie》1998,5(12):1347-1352
Persistent hyperinsulinemic hypoglycaemia of infancy (PHHI) is the most frequent cause of hypoglycaemia in infancy. Clinical presentation is heterogeneous, with variable onset of hypoglycaemia and response to diazoxide, and presence of sporadic or familial forms. Underlying histopathological lesions can be focal or diffuse. Focal lesions are characterised by focal hyperplasia of pancreatic islet-like cells, whereas diffuse lesions implicate the whole pancreas. The distinction between the two forms is important because surgical treatment and genetic counselling are radically different. Focal lesions correspond to somatic defects which are totally cured by limited pancreatic resection, whereas diffuse lesions require a subtotal pancreatectomy exposing to high risk of diabetes mellitus. Diffuse lesions are due to functional abnormalities involving several genes and different transmission forms. Recessively inherited PHHI have been attributed to homozygote mutations for the beta-cell sulfonylurea receptor (SUR1) or the inward-rectifying potassium-channel (Kir6.2) genes. Dominantly inherited PHHI can implicate the glucokinase gene, particularly when PHHI is associated with diabetes, the glutamate dehydrogenase gene when hyperammonaemia is associated, or another locus. 相似文献
99.
100.
OBJECTIVE: The ketogenic diet is a high-fat, low-protein, low-carbohydrate diet developed in the 1920s for the treatment of children with difficult to control seizures. Despite advances in both the pharmacotherapy and the surgery of epilepsy, many children continue to have difficult-to-control seizures. This prospective study sought to determine the ketogenic diet's effectiveness and tolerability in children refractory to today's medications. METHODS: One hundred fifty consecutive children, ages 1 to 16 years, virtually all of whom continued to have more than two seizures per week despite adequate therapy with at least two anticonvulsant medications, were prospectively enrolled in this study, treated with the ketogenic diet, and followed for a minimum of 1 year. Seizure frequency was tabulated from patients' daily seizure calendars and seizure reduction calculated as percentage of baseline frequency. Adverse events and reasons for diet discontinuation were recorded. RESULTS: The children (mean age, 5.3 years), averaged 410 seizures per month before the diet, despite an exposure to a mean of 6.2 antiepileptic medications. Three months after diet initiation, 83% of those starting remained on the diet and 34% had >90% decrease in seizures. At 6 months, 71% still remained on the diet and 32% had a >90% decrease in seizures. At 1 year, 55% remained on the diet and 27% had a >90% decrease in seizure frequency. Most of those discontinuing the diet did so because it was either insufficiently effective or too restrictive. Seven percent stopped because of intercurrent illness. CONCLUSIONS: The ketogenic diet should be considered as alternative therapy for children with difficult-to-control seizures. It is more effective than many of the new anticonvulsant medications and is well tolerated by children and families when it is effective. 相似文献