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71.
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
72.
Corzo D; Yunis JJ; Salazar M; Lieberman JA; Howard A; Awdeh Z; Alper CA; Yunis EJ 《Blood》1995,86(10):3835-3840
Genes of the major histocompatibility complex (MHC) have been associated with susceptibility to drug-induced adverse reactions. We previously found that clozapine-induced agranulocytosis (CA) is associated with the HLA-DRB1*0402, DRB4*0101, DQB1*0302, DQA1*0301 haplotype in Ashkenazi Jewish patients and with the HLA-DRB1*1601, DRB5*02, DQB1*0502, DQA1*0102 haplotype in non-Jewish patients. In the present study, we tested the hypothesis that the variants of the heat- shock protein 70 (HSP-70) encoded by the HSP-70 loci located within the MHC region and known to be involved in apoptosis and regulation of cell proliferation could play an important role in molecular mechanisms of CA. First, we analyzed HSP70-2 polymorphism in risk-associated haplotypes from HLA homozygous cells and normal individuals and confirmed that the HSP70-2 9-kb variant was associated invariably with DR4 (HLA-DRB1*0402, DQB1*0302) and DR2 (HLA-DRB1*01601, DQB1*0502, DQA1*0102 and HLA-DRB1*1501, DQB1*0602) haplotypes, which were the haplotypes found increased in Jewish and non-Jewish patients with CA, respectively. The 9.0-kb variant was also found to be associated with HLA-B44, DRB1*0401 and HLA-B44, DRB1*07 haplotypes. Second, in patients with CA (12 Ashkenazi Jewish and 20 non-Jewish patients), HSP70-1 A and HSP70-2 9.0-kb variants were associated with the MHC haplotypes found by us to be markers of susceptibility to CA. The clozapine-treated control group had an excess number of HSP70-1 C and HSP70-2 8.5-kb variants, consistent with genetic resistance to CA associated with those variants. This finding supports our hypothesis that a dominant gene within the MHC region (marked by HSP70-1 and HSP70-2), but not necessarily HLA, is associated with CA in two different ethnic groups. 相似文献
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74.
Laura Villarreal‐Martínez Jaime García‐Chvez Berenice Snchez‐Jara Aida Mashenka Moreno‐Gonzlez Janet Soto‐Padilla Efraín Aquino‐Fernndez Rogelio Paredes‐Aguilera Karla Maldonado‐Silva Cecilia Rodríguez‐Castillejos Ana Itamar Gonzlez‐vila María Mora‐Torres Hector Manuel Tiznado‐García Natalia Elizabeth Padilla‐Durn Nuria Citlali Luna‐Silva Eric Israel Gutirrez‐Jurez Jorge Nemi‐Cueto Claudia Sofia Gmez‐Gonzlez Ricardo De Len‐Figueroa Adela Lpez‐Miranda Mirna Guadalupe Ríos‐Osuna Edna Liliana Tamez‐Gmez Elio Aarn Reyes‐Espinoza Irving Armando Domínguez‐Varela Gerardo Gonzlez‐Martínez Elias Adn Godoy‐Salinas 《Haemophilia》2020,26(2):290-297
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77.
CA Tan D. del Gaudio M.A. Dempsey K. Arndt S. Botes A. Reeder S. Das 《Clinical genetics》2014,85(4):353-358
Primary Autosomal Recessive Microcephaly (MCPH) is characterized by congenital microcephaly usually without additional clinical findings. The most common gene implicated in MCPH is ASPM and a large percentage of mutations described have been homozygous and in consanguineous families primarily of East Asian and Middle Eastern origin. ASPM sequencing was performed on 400 patients between the years 2009 and 2012. Seventy of the patient samples were also analyzed for copy number changes in the ASPM gene. Forty protein truncating mutations, including 29 novel mutations, were identified in 39 patients with MCPH. Approximately one third of patients were compound heterozygotes, indicative of non‐consanguinity in these patients. In addition, 46 non‐synonymous variants were identified and interpreted as variants of uncertain significance. No deletion/duplication in ASPM was identified in the patients analyzed. A wide ethnic distribution was observed, including the first reported patients with ASPM‐related MCPH of Hispanic descent. Clinical information was collected for 26 of the ASPM‐positive patients and 41 of the ASPM‐negative patients. As more individuals are identified with MCPH, we anticipate that we will continue to identify ASPM mutation‐positive patients from all ethnic origins supporting the occurrence of this genetic condition beyond that of consanguineous families of certain ethnic populations. 相似文献
78.
Flora Maria Lorenzo Fortes Ney Boa Sorte Victor D Mariano La la D Andrade Fernanda A Oliveira Monique CA Santos Cl udia Ivanilda N dos Santos Catharina A Passos Mila P Pacheco Valdiana C Surlo Neog lia P de Almeida Jaciane AM Fontes r a M Pimentel Raquel Rocha Genoile Oliveira Santana 《World journal of gastroenterology : WJG》2020,26(44):6993-7004
BACKGROUNDThere has been an increase in cases of inflammatory bowel disease (IBD) in recent years. There is also greater access and availability of immunosuppressive and biological agents, which increase the risk of opportunistic infection despite improving the quality of life and promoting mucosal healing. Tuberculosis (TB) remains a public health problem, and it has a high incidence in several countries. Therefore, knowledge of the risk of developing TB in patients with IBD is important.AIMTo evaluate the risk of active TB in patients with IBD under treatment from an endemic area in Latin America.METHODSA standard questionnaire included demographic variables, clinical aspects of IBD disease, history of active TB during treatment, active TB characteristics and evolution, initial screening and results and time from the start of anti-tumor necrosis factor alpha (TNFα) to TB development.RESULTSAzathioprine, anti-TNFα and the combination of these two drugs were associated with a higher risk of active TB incidence. The TNFα blockers increased the relative risk of developing active TB compared to other treatments. All four multivariable models showed that the use of TNFα blockers alone or in combination with azathioprine was an important risk factor for the incidence of active TB. After adjustment for sex, age, type of IBD and latent TB, anti-TNFα with azathioprine increased the relative risk to 17.8 times more than conventional treatment. Late TB, which was diagnosed 3 mo after the start of anti-TNFα, was the most frequent.CONCLUSIONTreatment with anti-TNFα increased the risk of active TB in IBD patients from an endemic area in Latin America. This risk was increased when anti-TNFα was combined with azathioprine. The time from the beginning of the treatment to the active TB diagnosis suggests a new TB infection. 相似文献
79.
Harry Salinas Abdulmentin Dursun Ioannis Konstantinidis Deanna Nguyen Paul Shellito Richard Hodin Liliana Bordeianou 《International journal of colorectal disease》2012,27(11):1479-1483
Purpose
Malnutrition is a frequent problem in patients with ulcerative colitis (UC) leading to increased postoperative complication rates. Preoperative total parenteral nutrition (TPN) has been shown to reduce complications in some subgroups of patients, but has not been studied in UC. We investigated the impact of preoperative TPN on postoperative complication rates in patients undergoing surgery for UC.Methods
This paper is a review of 235 patients who underwent surgery for UC; 56 received preoperative TPN and 179 did not. Postoperative complication rates were compared.Results
Both had similar rates of anastomotic leak (5.4 vs. 2.8?%, p?=?0.356), infection (12.5 vs. 20.1?%, p?=?0.199), ileus/bowel obstruction (21.4 vs. 15.6?%, p?=?0.315), cardiac complications (3.6 vs. 0?%, p?=?0.056), wound dehiscence (3.6 vs. 1.7?%, p?=?0.595), reoperation (10.7 vs. 3.9?%, p?=?0.086), and death (1.8 vs. 0?%, p?=?0.238). The TPN group was more malnourished (albumin 2.49 vs. 3.45, p?<?0.001), more often on steroids (83.9 vs. 57.5?%, p?<?0.001), had more emergent surgery (10.7 vs. 3.4?%, p?=?0.029), more severe colitis (89.3 vs. 65.9?%, p?=?0.001), and lower Surgical Apgar Score (6.15 vs. 6.57, p?=?0.033). After controlling for these with logistic regression, the TPN group still had higher complication rates (OR 2.32, p?=?0.04). When line infections were excluded, TPN did not significantly affect outcomes (OR 1.5, p?=?0.311)Conclusion
There were no differences in postoperative complications when line infections were excluded. Our data does not support routine preoperative TPN in patients with UC. However, it may lead to equal surgical outcomes in the sickest and most malnourished patients at the cost of line-related morbidity. 相似文献80.
Ewing Duque Arturo Mangas Pablo Salinas Zaida Díaz-Cabiale José Angel Narváez Rafael Coveñas 《Brain structure & function》2013,218(1):131-149
We have studied the distribution of alpha-neo-endorphin- or neurokinin B-immunoreactive fibres and cell bodies in the adult human brainstem with no prior history of neurological or psychiatric disease. A low density of alpha-neo-endorphin-immunoreactive cell bodies was only observed in the medullary central gray matter and in the spinal trigeminal nucleus (gelatinosa part). Alpha-neo-endorphin-immunoreactive fibres were moderately distributed throughout the human brainstem. A high density of alpha-neo-endorphin-immunoreactive fibres was found only in the solitary nucleus (caudal part), in the spinal trigeminal nucleus (caudal part), and in the gelatinosa part of the latter nucleus. Neurokinin B-immunoreactive cell bodies (low density) were found in the periventricular central gray matter, the reticular formation of the pons and in the superior colliculus. The distribution of the neurokinin-immunoreactive fibres was restricted. In general, for both neuropeptides the density of the immunoreactive fibres was low. In the human brainstem, the proenkephalin system was more widely distributed than the prodynorphin system, and the preprotachykinin A system (neurokinin A) was more widely distributed than the preprotachykinin B system (neurokinin B). 相似文献