Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0016382 (flushing)
 6,387 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Octreotide is a synthetic octapeptide somatostatin analogue which has higher potency and longer duration of action than the natural hormone. It is effective after subcutaneous administration and no rebound hypersecretion has been observed. Pharmacological effects of octreotide include inhibition of numerous hormones (growth hormone, TSH, insulin, glucagon and all gut hormones), of exocrine secretion (gastric acid, pancreatic enzyme), and of small-bowel absorption. This review deals with clinical application of octreotide in endocrine disorder. In patients with acromegaly octreotide treatment results in decrease of growth hormone (GH) and IGF-I together with tumour shrinkage and clinical improvement. Although variability in response to treatment is obvious for majority of patients the most effective dose is 100 mcg three times daily subcutaneously. Normalization of GH levels could be achieved in more than 50% of treated patients. It has also been shown that octreotide could be effective in TSH secreting pituitary adenoma, ACTH secreting adenoma as well as in non-secretory pituitary tumours. A marked biochemical and clinical responses together with longer survival have been reported in most of the patients with gastroenteropancreatic (GEP) tumours. Patients who benefit the most from octreotide therapy are those with carcionid syndrome (successful control of diarrhoea, flushing episodes and wheezing) and VIPomas (control of diarrhoea). In patients with insulin-dependent diabetes mellitus (IDDM) octreotide suppresses GH levels, postprandial blood glucose increases with resultant decrease in daily insulin requirements. In women with polycystic ovary syndrome (PCOS) octreotide has inhibitory effect on serum LH and ovarian androgens. This could have beneficial effect on ovulatory performance in women with PCOS.
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PMID:[Clinical use of octreotide (Sandostatin) in endocrinology]. 799 11

Neuroendocrine gut and pancreatic tumors have over the years presented a therapeutic challenge. The patients present with a wide range of clinical symptoms related to hormone production that can sometimes be easily managed but are sometimes life threatening. The most frequent clinical symptom related to endocrine gut tumors is the carcinoid syndrome, with flushing, diarrhea, bronchoconstriction, and right heart failure. Until the middle of the 1980s, when a patient was not cured by surgery, very little could be offered except chemotherapy. Biotherapy has revolutionized the treatment of malignant neuroendocrine gut and pancreatic tumors, in which both interferon-alpha and somatostatin analogues improved the quality of life for these patients and possibly also increased survival. Chemotherapy, with response rates of 40% to 60% in endocrine pancreatic tumors, is still first-line treatment in this group of patients, whereas in patients with carcinoids of the gut, no beneficial value of chemotherapy so far has been noticed. Both interferon-alpha and somatostatin analogues provide biochemical responses in 40% to 70% of patients with carcinoid tumors, whereas significant tumor reduction is only noticed in a few cases. Development of biotherapy is just at its beginning, and in the future, when we have learned more about tumor biology and mechanisms of action of these treatments, even better therapeutic results might be encountered. Combinations of biotherapy with chemotherapy as well as combinations of different biotherapies are now under clinical investigation.
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PMID:Chemotherapy and biotherapy in neuroendocrine tumors. 809 14

The dynamics of intestinal absorption, blood concentration and distribution of thiamin, biotin, nicotinate, riboflavin, pantothenate, various folates (folic acid, folinic acid, pteroyltriglutamate), vitamins A, E, C, B12, and B6 were monitored in 12 patients by multiple simultaneous sampling of blood obtained by combined catheterization of portal vein, hepatic vein, and femoral artery after vitamin ingestion. All water-soluble vitamins proved elevated after vitamin ingestion principally in portal blood within 10 minutes as compared with hepatic and femoral blood. Elevated vitamin levels in portal blood--compared to hepatic and femoral blood--remained high even after 120 min. indicating that absorption from the gut was still progressing. In contrast, ingestion of the fat-soluble vitamins A and E evoked no elevated vitamin activity in portal blood. Within 10 min. after vitamin ingestion, all folates were converted into reduced and methylated 5-methyltetrahydrofolate (5-CH3THF) on passage through the gut. At this time, portal blood elevation of 5-CH3THF persisted before its elevation in hepatic or femoral blood. Presumably, the elevation was not due to the flushing of stored 5-CH5THF from tissues but rather of folate conversion to 5-CH3THF upon gut passage. The significance of these findings is discussed.
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PMID:Vitamin activities in human portal, hepatic and femoral blood after vitamin ingestion. 820 Jul 51

The authors report their experience with octreotide in 20 patients (median age 57 years, 10 M, 10 F) from 1984 to 1991; 16 had metastatic APUDoma: 1 PPoma with VIPoma, 1 glucagonoma, 5 gastrinoma including 1 associated to PP-oma, 9 mid-gut carcinoid; 3 patients had multiple-endocrine neoplasia type I (MEN-I) with Zollinger-Ellison syndrome (ZES) and 1 patient a non-metastatic VIPoma. Octreotide (200-750 micrograms/day) was administered bid or tid with regular laboratory controls and morphological assessment. There was a striking improvement of symptoms, particularly in the carcinoid group (reduction of flushing in all patients and of diarrhoea in 3/5), in the patient with gastrinoma + acromegaly (regression of congestive heart failure) and in the patient with non-metastatic VIPoma. The hormonal markers were markedly reduced, particularly gastrin, PP (except in the patient with PPoma + VIPoma), VIP, GH and Somatomedin-C and urinary 5HIAA in 4/9 patients with carcinoid. There was only one partial regression of metastases (gastrinoma) and 4 apparent stabilizations of tumour growth, in the 16 metastatic cases. Among them, 4 patients died: 1 glucagonoma, 1 PPoma + VIPoma, 2 mid-gut carcinoids after a treatment of 5, 16, 30, 36 months, respectively. The patient with acromegaly + ZES died after 6 years of treatment at age 81. A patient with prolactinoma, resected insulinoma, hyperparathyroidism and ZES was not improved by a short course of octreotide (hypoglycemia); he died later of recurrent insulinoma. In conclusion, octreotide is a useful drug to control most of the symptoms related to gut endocrine tumours; it may inhibit tumour growth.
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PMID:Use of octreotide in the treatment of digestive neuroendocrine tumours. Seven year experience in 20 cases including 9 cases of metastatic midgut carcinoid and 5 cases of metastatic gastrinoma. 826 71

Carcinoids, tumors arising from enterochromaffin cells, represent the most common type of gastrointestinal endocrine neoplasm; they are often multiple and may appear anywhere in the gut. Carcinoid tumors may also occur in bronchi and ovaries. Classic symptomatology includes secretory diarrhea, flushing, edema, bronchospasm and cutaneous teleangectasias; however, over 30% of patients with demonstrably elevated serotonin levels may not exhibit any symptoms at all. The diagnosis of carcinoid tumor is typically made by measurement of 24-hour urinary excretion of 5-hydroxyindoloacetic acid. Commonly, tumor localisation is established with CT, US, NMR and arteriography. MIBG scintigraphy is also used to visualize tumors deriving from neuroendocrine cells as carcinoid. These tumors may express somatostatin receptors located on the cell surface. Therefore 111In Octreotide (Octreoscan), a somatostatin analogue, can be employed for tumor localisation. A 32-years-old man with liver metastases secondary to a carcinoid tumor of unknown origin is presented. Classic carcinoid symptoms were absent. Diagnosis was supported by elevated values of urinary 5-hydroxyindolocetic acid and liver fine-needle aspiration. Abdominal US and CT scan detected only liver masses but not the primary tumor. Arteriography was not performed. 131I MIBG and 111I octreotide scans both failed in locating the primary cancer too; only the second tracer showed marked uptake in liver metastases. Beside localization, these two tracers give also informations about the following therapy especially in malignant tumors where local resection isn't an adequate treatment.
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PMID:131I MIBG/111In octreotide mismatch in a patient with liver metastases secondary to a carcinoid of unknown origin. 853 97

Tachykinins are a family of peptides that may be present in and secreted from carcinoid tumours of mid-gut origin. They are likely to play a role in the pathogenesis of, e.g. the flush, dyspnoea and valvular heart disease seen in the carcinoid syndrome. Since tachykinins are secreted from the tumour into the circulation in bursts, coinciding with flushing attacks, and have short half-lives, we anticipated that analysis of 24-h urine excretion of immunoreactive tachykinin metabolites might prove to be a more sensitive and stable parameter for monitoring than tachykinin-like immunoreactivity in plasma. The study included 48 patients hospitalized for treatment of advanced carcinoid tumours and 32 healthy controls. The urine excretion of tachykinin-like immunoreactive metabolites in the carcinoid patients (median 27.5 pmol 24 h-1, interquartile range (IQR) 8.5-51.0 pmol 24 h-1) was significantly (p<0.001) higher than that in the 32 healthy subjects (median 3.0 pmol 24 h-1, IQR 0.9-4.20 pmol 24 h-1). Of the patients, 38 (79%) had elevated 24-h urine excretion of tachykinin-like immunoreactive metabolites while 31 (64%) had elevated plasma concentrations of tachykinin-like immunoreactive metabolites. Of the patients, 27 (56%) had elevated concentrations of tachykinin-like immunoreactive metabolites both in plasma and urine, 12 (25%) had elevated concentrations only in urine excretion, 3 (6%) had elevated concentrations of only plasma tachykinin-like immunoreactive metabolites and 7 (14%) had elevation of neither plasma nor urine concentrations. Analysis by means of different column chromatographic techniques indicated that the immunoreactive material was heterogeneous, with some components co-eluting with oxidized neurokinin A (NKA) and neuropeptide K (NPK). The urine tachykinin-like immunoreactivity correlates well with that of plasma, but is a slightly more sensitive indicator of elevated tachykinin-like immunoreactivity, probably since levels of urine tachykinin-like immunoreactive metabolites reflect the overall amount of the latter secreted into the circulation during 24 h.
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PMID:Immunoreactive tachykinins in 24-h collections of urine from patients with carcinoid tumours: characterization and correlation with plasma concentrations. 890 38

Human saliva contains a number of physical physicochemical, and chemical agents that protect oral tissues against noxious compounds, in particular those produced by various microorganisms. Among such protective factors, the flushing effect of saliva flow is the most important one, not only because it so effectively removes exogenous and endogenous microorganisms and their products into the gut but also because a steady supply of saliva guarantees continuous presence of both non-immune and immune factors in the mouth. A great number of studies with controversial results have been published regarding various individual agents and their possible association to oral health, particularly to dental caries. It appears that no single chemical agent is far more important than the others. For example, patients with selective IgA deficiency have normal levels of non-immune defense factors and often display a compensatory increase in the other immunoglobulin isotypes. The concerted action of all agents in whole saliva, both saliva- and serum-derived, provides a multifunctional protective network that is collapsed only if salivary flow rate is substantially reduced. In this mixture of defense factors, many show additive or even synergistic interactions against oral pathogens. Increased knowledge of the molecular functions of various agents has made it possible to prepare oral hygiene product that include host-derived antimicrobial agents instead of synthetic agents. Although the clinical efficacy of such products is still unsatisfactory and poorly described, new technologies, for example in the production of specific antibodies against oral pathogens, may considerably improve the antimicrobial power of these products.
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PMID:Antimicrobial function of human saliva--how important is it for oral health? 986 91

Previous studies have shown that infaunal deposit feeders may enhance the loss of organic contaminants from sediments. However, the extent to which this occurs as a result of sediment microbial stimulation, porewater flushing, or biotransformation by infauna remains unclear. The purpose of this study was to determine whether the infaunal polychaete Capitella sp. I is able to metabolize the polycyclic aromatic hydrocarbon (PAH) fluoranthene and to provide an initial characterization of the metabolites produced. Our results showed that Capitella sp. I is able to metabolize fluoranthene to more hydrophilic products and that, after 24 h in clean sediment, fluoranthene could no longer be detected in worm tissues whereas a number of fluoranthene-derived metabolites were present. None of the metabolites released or retained by worms resembled known bacterial metabolites, suggesting that Capitella, and not bacteria associated with its gut or body surface, were responsible for the biotransformation of fluoranthene in our system. On the basis of ultraviolet maxima, peak shape, relative height, and order of elution, tentative identities of two metabolites (i.e., 3- and 8-hydroxyfluoranthene) are proposed. The results demonstrate that, in addition to their effects on sediment geochemical properties, infaunal polychaetes such as Capitella can enhance the degradation of sediment-associated contaminants by directly metabolizing them.
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PMID:Metabolism of the polycyclic aromatic hydrocarbon fluoranthene by the polychaete Capitella capitata species I. 1133 63

Carcinoids are neuroendocrine tumours of the gut which may also be found in the bronchus, pancreatic islets and retroperitoneum. They probably arise from gastrointestinal or bronchopulmonary pluripotential stem cells. Carcinoid tumours derived from these cells are potentially malignant; the strength of the tendency for aggressive growth correlates with the site of origin, depth of local penetration and the size of the tumour. Carcinoids occur sporadically or result from specific hereditary tumour syndromes. Mutations and/or aberrant expression of specific genes induce and promote tumour growth. Clinical features include local symptoms due to angulation or obstruction and hepatomegaly due to liver metastases. The carcinoid syndrome commonly involves flushing, diarrhoea, bronchospasm and hypotension. Other distinct syndromes may be caused by tumour release of products that may also be used as biochemical markers in diagnosis and follow-up. Scanning using radiolabelled octreotide, an analogue of somatostatin, sensitively identifies occult primary and metastatic deposits. Localized carcinoid tumours should be resected. Some patients benefit from hepatic resection. Palliation of symptoms is best achieved with octreotide. Hepatic artery chemoembolization may produce long-acting palliation. Further genetic characterization of the different types and stages of carcinoid development as well as assessment of gene expression profiles may improve differential diagnosis, prognosis and treatment.
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PMID:The spectrum of carcinoid tumours and carcinoid syndromes. 1462 99

The ability of some insects to engage in complex orchestrations of tracheal gas exchange has been well demonstrated, but its evolutionary origin remains obscure. According to a recently proposed hypothesis, insects may employ spiracular control of gas exchange to guard tissues against long-term oxidative damage by using the discontinuous gas-exchange cycle (DGC) to limit internal oxygen partial pressure (PO2). This manuscript describes a different approach to oxygen guarding in the lower termite Zootermopsis nevadensis. These insects do not display a DGC but respond to elevated oxygen concentrations by restricting spiracular area, resulting in a transient decline in CO2 emission. High internal CO2 concentrations are then maintained; restoring normoxia results in a transient reciprocal increase in CO2 emission caused by release of excess endotracheal CO2. These changes in spiracular area reflect active guarding of low internal O2 concentrations and demonstrate that regulation of endotracheal hypoxia takes physiological priority over prevention of CO2 build-up. This adaptation may reflect the need to protect oxygen-sensitive symbionts (or, gut bug guarding). Termites may eschew the DGC because periodic flushing of the tracheal system with air may harm the obligate anaerobes upon which the lower termites depend for survival on their native diet of chewed wood.
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PMID:To DGC or not to DGC: oxygen guarding in the termite Zootermopsis nevadensis (Isoptera: Termopsidae). 1632 48


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