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21.
BACKGROUND & AIMS: The functional significance of intestinal hyperplasia stimulated by insulin-like growth factor (IGF)-I is unclear and has not been studied in a model of mucosal atrophy induced by total parenteral nutrition (TPN). The aim of this study was to determine how IGF-I affects intestinal structure and epithelial function in the absence of luminal nutrition caused by TPN. METHODS: Rats were maintained with TPN with or without IGF-I (800 micrograms/day), and jejunal histology and epithelial ion transport were measured after 5 days. In a third TPN group without IGF-I, a short-term dose of IGF-I was added during in vitro flux chamber experiments. RESULTS: Rats given TPN with IGF-I had greater jejunal mucosal weight, greater protein and DNA content, and increased villus height and crypt depth compared with rats given TPN only. TPN increased ionic permeability and ion transport responses to secretory and absorptive agents. IGF-I in vivo reversed most of these changes; IGF-I in vitro enhanced sodium-dependent glucose absorption but had no other effects. CONCLUSIONS: Coinfusion of recombinant human IGF-I with TPN solution stimulates intestinal hyperplasia and attenuates transport changes induced by TPN. The latter effect seems to be primarily associated with the growth state of the epithelium. (Gastroenterology 1996 Dec;111(6):1501-8) 相似文献
22.
Moody J Cosgrove SE Olmsted R Septimus E Aureden K Oriola S Patel GW Trivedi KK 《American journal of infection control》2012,40(2):94-95
It is clear that the widespread and injudicious use of antimicrobials has greatly increased the presence of MDROs that threaten the health of all. There is worldwide acknowledgement that this threat is growing, and that prudent use of antimicrobials combined with infection prevention can prevent harm and improve patient safety. Antimicrobial stewardship programs must harness the talents of all members of the health care team to effectively identify the organism, determine its susceptibility, institute any precautions required, and prescribe the narrowest-acting antibiotic that will destroy it. IPs/HEs play a pivotal role in this approach, by assisting with early organism and infected patient identification, by promoting compliance with standard and transmission-based precautions and other infection prevention strategies such as care bundle practices, hand hygiene, and by educating staff, patients, and visitors. 相似文献
23.
PS Spencer K Vandemaele M Richer VS Palmer S Chungong M Anker Y Ayana ML Opoka BN Klaucke A Quarello JK Tumwine 《African health sciences》2013,13(2):183-204
Background
Nodding Syndrome is a seizure disorder of children in Mundri County, Western Equatoria, South Sudan. The disorder is reported to be spreading in South Sudan and northern Uganda.Objective
To describe environmental, nutritional, infectious, and other factors that existed before and during the de novo 1991 appearance and subsequent increase in cases through 2001.Methods
Household surveys, informant interviews, and case-control studies conducted in Lui town and Amadi village in 2001–2002 were supplemented in 2012 by informant interviews in Lui and Juba, South Sudan.Results
Nodding Syndrome was associated with Onchocerca volvulus and Mansonella perstans infections, with food use of a variety of sorghum (serena) introduced as part of an emergency relief program, and was inversely associated with a history of measles infection. There was no evidence to suggest exposure to a manmade neurotoxic pollutant or chemical agent, other than chemically dressed seed intended for planting but used for food. Food use of cyanogenic plants was documented, and exposure to fungal contaminants could not be excluded.Conclusion
Nodding Syndrome in South Sudan has an unknown etiology. Further research is recommended on the association of Nodding Syndrome with onchocerciasis/mansonelliasis and neurotoxins in plant materials used for food. 相似文献24.
Maggie KM Ma Desmond YH Yap Terence PS Yip Sing Leung Lui Wai Kei Lo 《Nephrology (Carlton, Vic.)》2013,18(5):365-368
Published literature on fracture in dialysis patients seldom addressed the effect of co‐morbidity and malnutrition. In this study, we reported the incidence and risk factors for fracture in peritoneal dialysis patients. Peritoneal dialysis patients who had fractures between 2006 and 2011 were recruited. Demographic data, details of fracture, Charlson Co‐morbidity Index (CCI) and biochemical parameters were also collected. Non‐fracture controls, matched for age, gender and duration of dialysis, were also recruited at ratio 1:1 for fracture risk analysis. The incidence of fracture was 1 in 37 patient‐years. The commonest site of fracture was neck of femur (n = 16, 55.2%). Twenty‐four patients (82.8%) developed fracture after slip and fall injury. Eight out of 17 self‐ambulatory patients (47.1%) became non‐ambulatory after fracture. Infection was the commonest complication during hospitalization. Univariant analysis demonstrated high CCI (P = 0.001), hypoalbuminaemia (P < 0.001), loss of self autonomy (P = 0.006) and non‐ambulatory state (P = 0.011) significantly associated with increased fracture risk. However, only CCI (odds ratio (OR) 1.373, P = 0.028) and albumin (OR 0.893, P = 0.025) increased fracture risk significantly on multivariant analysis. Bone profile and parathyroid hormone were not significant risk factors. To conclude, fracture associated with adverse outcome in peritoneal dialysis patients. High CCI score and hypoalbuminaemia significantly increase risk of fracture. 相似文献
25.
SMAD4 mutations in colorectal cancer probably occur before chromosomal instability, but after divergence of the microsatellite instability pathway 总被引:9,自引:0,他引:9
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Woodford-Richens KL Rowan AJ Gorman P Halford S Bicknell DC Wasan HS Roylance RR Bodmer WF Tomlinson IP 《Proceedings of the National Academy of Sciences of the United States of America》2001,98(17):9719-9723
Loss of chromosome 18q21 is well documented in colorectal cancer, and it has been suggested that this loss targets the DCC, DPC4/SMAD4, and SMAD2 genes. Recently, the importance of SMAD4, a downstream regulator in the TGF-beta signaling pathway, in colorectal cancer has been highlighted, although the frequency of SMAD4 mutations appears much lower than that of 18q21 loss. We set out to investigate allele loss, mutations, protein expression, and cytogenetics of chromosome 18 copy number in a collection of 44 colorectal cancer cell lines of known status with respect to microsatellite instability (MSI). Fourteen of thirty-two MSI(-) lines showed loss of SMAD4 protein expression; usually, one allele was lost and the other was mutated in one of a number of ways, including deletions of various sizes, splice site changes, and missense and nonsense point mutations (although no frameshifts). Of the 18 MSI(-) cancers with retained SMAD4 expression, four harbored missense mutations in the 3' part of the gene and showed allele loss. The remaining 14 MSI(-) lines had no detectable SMAD4 mutation, but all showed allele loss at SMAD4 and/or DCC. SMAD4 mutations can therefore account for about 50-60% of the 18q21 allele loss in colorectal cancer. No MSI(+) cancer showed loss of SMAD4 protein or SMAD4 mutation, and very few had allelic loss at SMAD4 or DCC, although many of these MSI(+) lines did carry TGFBIIR changes. Although SMAD4 mutations have been associated with late-stage or metastatic disease, our combined molecular and cytogenetic data best fit a model in which SMAD4 mutations occur before colorectal cancers become aneuploid/polyploid, but after the MSI(+) and MSI(-) pathways diverge. Thus, MSI(+) cancers may diverge first, followed by CIN(+) (chromosomal instability) cancers, leaving other cancers to follow a CIN(-)MSI(-) pathway. 相似文献
26.
Oxidative metabolism of the human eosinophil 总被引:14,自引:1,他引:14
We have compared the oxidative metabolism of human eosinophils (80%-90% purity) to that of neutrophils. Hexose monophosphate (HMP) shunt activity of eosinophils was higher than that of neutrophils under either resting or phagocytizing conditions. Eosinophil HMP shunt activity also was stimulated by phorbol myristate acetate, a membrane- active agent. Eosinophils showed a marked incorporation of 125I into trichloroacetic acid-insoluble material under resting conditions, which increased markedly during phagocytosis. Eosinophils likewise showed a greater reduction of nitroblue tetrazolium dye during phagocytosis than did neutrophils. Measurement of other parameters of oxidative metabolism indicated that eosinophils generated superoxide anion following phagocytosis and also elicited a burst of chemiluminescence similar to that observed during phagocytosis by neutrophils. Measurement of NADPH oxidase activity demonstrated that this enzyme was 3-6 times more active in fractions isolated from eosinophils than in corresponding fractions isolated from neutrophils; this was observed over a range of substrate concentrations. The eosinophil enzyme sedimented differently than the neutrophil enzyme with differential centrifugation; neither showed sedimentation characteristics of peroxidase. These data indicate that eosinophils possess a similar, although in some ways more potent, oxidative burst than neutrophils and are consistent with a role for NADPH oxidase in the initiation of that burst. 相似文献
27.
Jane Wolstenholme Francesco Fusco Alastair M. Gray Joanna Moschandreas Pradeep S. Virdee Sharon Love Guy Van Hazel Peter Gibbs Harpreet S. Wasan Ricky A. Sharma 《International journal of cancer. Journal international du cancer》2020,147(4):1078-1085
Selective internal radiotherapy (SIRT) is a liver-directed treatment involving the injection of yttrium-90 microspheres into the blood supply of liver tumours. There are very few studies assessing health-related quality of life (HRQOL) in patients treated with SIRT. Patients with liver metastases from colorectal cancer (CRC) were randomised in the FOXFIRE (FFr; ISRCTN83867919), SIRFLOX (SF; NCT00724503) and FOXFIRE-Global (FFrG; NCT01721954) trials of first-line oxaliplatin–fluorouracil (FOLFOX) chemotherapy combined with SIRT versus FOLFOX alone. HRQOL was assessed using the three-level EQ-5D, European Organisation for Research and Treatment of Cancer Quality of Life (EORTC QLQ-C30) and EORTC Colorectal Liver Metastases cancer module (EORTC QLQ-LMC21) at baseline, ≤3 months, 6 months, 12 months and annually thereafter from randomisation, and at disease progression. Analyses were conducted on an intention-to-treat basis. In total, 554 patients were randomised to SIRT + FOLFOX and 549 patients to FOLFOX alone. HRQOL was statistically significant lower in SIRT + FOLFOX patients ≤3 months after SIRT administration in all three instruments, particularly global health, physical and role functioning and symptoms of fatigue, nausea/vomiting and appetite loss. By accepted thresholds, these differences were deemed not clinically important. Differences between SIRT + FOLFOX and FOLFOX alone over the 2-year follow up and at disease progression were also not clinically important. Although there is some decrease in HRQOL for up to 3 months following SIRT, the addition of SIRT to FOLFOX chemotherapy does not change HRQOL to a clinically important degree in metastatic CRC patients. 相似文献
28.
Suhal S Mahid Daniel W Colliver Nigel PS Crawford Benjamin D Martini Mark A Doll David W Hein Gary A Cobbs Robert E Petras Susan Galandiuk 《BMC medical genetics》2007,8(1):28
Background
N-acetyltransferase 1 (NAT1) and 2 (NAT2) are polymorphic isoenzymes responsible for the metabolism of numerous drugs and carcinogens. Acetylation catalyzed by NAT1 and NAT2 are important in metabolic activation of arylamines to electrophilic intermediates that initiate carcinogenesis. Inflammatory bowel diseases (IBD) consist of Crohn's disease (CD) and ulcerative colitis (UC), both are associated with increased colorectal cancer (CRC) risk. We hypothesized that NAT1 and/or NAT2 polymorphisms contribute to the increased cancer evident in IBD. 相似文献29.
HW Schytz T Wienecke PS Oturai J Olesen & M Ashina 《Cephalalgia : an international journal of headache》2009,29(2):258-268
The parasympathetic nervous system is likely to be involved in migraine pathogenesis. We hypothesized that the cholinomimetic agonist carbachol would induce headache and vasodilation of cephalic and radial arteries. Carbachol (3 µg/kg) or placebo was randomly infused into 12 healthy subjects in a double-blind crossover study. Headache was scored on a verbal rating scale from 0–10. Velocity in the middle cerebral artery (VMCA ) and diameter of the superficial temporal artery (STA) and radial artery (RA) were recorded. Nine participants developed headache after carbachol compared with three after placebo. The area under the curve for headache was increased after carbachol compared with placebo both during infusion (0–30 min) ( P = 0.042) and in the postinfusion period (30–90 min) ( P = 0.027). Carbachol infusion caused a drop in VMCA ( P = 0.003) and an increase in STA diameter ( P = 0.006), but no increase in the RA diameter ( P = 0.200). In conclusion, the study demonstrated that carbachol caused headache and dilation of cephalic arteries in healthy subjects. 相似文献
30.