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81.
82.
Characterization of Leishmania species from Peru 总被引:1,自引:0,他引:1
G G Romero M Arana M López I Montoya R Bohl M Campos J Arévalo A Llanos 《Transactions of the Royal Society of Tropical Medicine and Hygiene》1987,81(1):14-24
Twenty-six isolates of Leishmania parasites of Peruvian origin were studied by isoenzyme electrophoresis of four marker enzymes (ASAT, ALAT, G6PD and GPI), kinetoplast DNA hybridization and monoclonal antibody binding and compared with marker strains of the New World organisms L. b. braziliensis, L. b. guyanensis, L. m. mexicana and L. m. amazonensis. 12 of the isolates studied were of Andean origin; 11 of these were isolated from patients with Andean cutaneous leishmaniasis. The organisms originating from the Peruvian Amazonian forest were isolated from patients with cutaneous (12 cases) or mucocutaneous (2 cases) leishmaniasis. One of the Andean isolates was obtained from an infected phlebotomine vector. 25 of the new isolates were identified as L. braziliensis ssp. according to the three techniques employed. The results of monoclonal antibody binding showed that 23 of the isolates were indistinguishable from L. b. braziliensis. Two isolates identified as L. braziliensis ssp. according to their isoenzyme profiles and k-DNA hybridization patterns could not be classified at the subspecies level. The isolate obtained from the phlebotomine vector could not be identified. No evidence of the existence of parasites of the L. mexicana complex in Peruvian territory was found in this study. The results obtained show a remarkable similarity between Leishmania of Andean origin and L. b. braziliensis. 相似文献
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Bayés B Lauzurica R Granada ML Serra A Bonet J Fontseré N Salinas I Romero R 《Transplantation》2004,78(1):26-30
BACKGROUND: New-onset diabetes mellitus after transplantation (NODAT) is a severe complication of kidney transplantation (KTx) with negative effects upon patient and graft survival. Several risk factors for NODAT have been described; however, the search for an early predictive marker is ongoing. It has recently been demonstrated that high concentrations of adiponectin (APN), which is an adipocyte-derived peptide with antiinflammatory and insulin-sensitizing properties, protect against future development of type 2 diabetes in healthy individuals. The purpose of this report was to study pretransplant insulin resistance and analyze pretransplant serum leptin and APN levels as independent risk factors for the development of NODAT. METHODS: A total of 68 KTx patients were studied [mean age, 48 +/- 11 years; 70% males; body mass index (BMI), 25 +/- 3 kg/m]; 31 KTx patients with NODAT and 37 KTx patients without NODAT (non-NODAT) with similar age, sex, BMI, immunosuppression, and posttransplant time were studied. All patients received prednisone and calcineurin inhibitors (75% tacrolimus and 25% cyclosporine A), and 76% of patients received mycophenolate mofetil. Family history of diabetes mellitus was recorded. Pretransplant homeostasis model assessment for insulin resistance (HOMA-IR) index was calculated from fasting plasma glucose and insulin. Pretransplant serum leptin and APN levels were determined by radioimmunoassay. RESULTS: NODAT patients showed higher pretransplant plasma insulin concentrations [NODAT, 13.4 (11-22.7) microIU/mL; non-NODAT, 10.05 (7.45-18.4) microIU/mL; P=0.049], HOMA-IR index [NODAT, 4.18 (2.49-5.75); non-NODAT, 2.63 (1.52-4.68); P=0.043], and lower pretransplant serum APN concentration [NODAT, 8.78 (7.2-11.38) microg/mL; non-NODAT, 11.4 (8.56-15.27) microg/mL, P=0.012]. Inverse correlations between APN and BMI (r=-0.33; P=0.014) and APN and HOMA-IR index (r=-0.39; P=0.002) and between APN and NODAT (r=-0.31; P=0.011) were observed. Multiple logistic regression analysis showed the patients with lower pretransplant APN concentrations to be those at greater risk of developing NODAT [Odds Ratio=0.832 (0.71-0.96); P=0.01]. CONCLUSION: Pretransplant serum APN concentration is an independent predictive factor for NODAT development in kidney-transplanted patients. 相似文献
85.
Acute otomastoiditis and its complications: role of CT 总被引:2,自引:0,他引:2
Acute bacterial (suppurative) otomastoiditis responds to antibiotic treatment; radiologic study is required only when there is clinical suggestion of coalescent mastoiditis, intracranial complications, or an underlying chronic disease. Computed tomography (CT) is the method of choice for evaluating otogenic intra- or extra-cranial complications. CT scans can show stages of disease progression when infection has spread by way of soft tissue, blood, and bone pathways into the dural venous sinuses, meninges, labyrinth, facial nerves, epidural and other intracranial spaces. When there is clinical suggestion of acute coalescent mastoiditis, a CT scan of the temporal bone can confirm the presence of rarefying osteitis, coalescence of the air cells, and subperiosteal abscess. 相似文献
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G. Arismendi-Morillo I. Hernández E. Mengual N. Abreu N. Molero A. Fuenmayor G. Romero M. Lizarzábal 《Revista de gastroenterologia de Mexico》2013,78(3):135-143
Background/AimSeverity of chronic gastritis associated with Helicobacter pylori infection (CGAHpI) could play a role in evaluating the potential risk to develop gastric cancer. Our aim was to estimate the risk for gastric cancer in a clinical setting, according to histopathologic criteria, by applying the gastric cancer risk index (GCRI)MethodsHistopathologic study of the gastric biopsies (corpus-antrum) from consecutive adult patients that underwent gastroesophageal duodenoscopy was carried out, and the GCRI was applied in patients presenting with CGAHpI.ResultsOne hundred eleven patients (77% female) with a mean age of 38.6±13.1 years were included. Active Helicobacter pylori infection (aHpi) was diagnosed in 77 cases (69.40%). In 45% of the cases with aHpi, pangastritis (23%) or corpus-predominant gastritis (22%) was diagnosed. Nine cases were diagnosed with intestinal metaplasia (8%), 7 of which (77.70%) were in the aHpi group. Twenty one percent of the patients with aHpi had a GCRI of 2 (18.10%) or 3 (2.50%) points (high risk index), while 79.10% accumulated a GCRI of 0 or 1 points (low risk index). Of the patients with no aHpi, none of them had 3 points (p=0.001). Of the 18 patients that accumulated 2 or 3 points, 6 (33.30%) presented with intestinal metaplasia (all with pangastritis and corpus-predominant gastritis), of which 4 cases (66.60%) had aHpi.ConclusionsThe estimated gastric cancer risk in patients with CGAHpI in the clinical setting studied was relatively low and 5% of the patients had a histopathologic phenotype associated with an elevated risk for developing gastric cancer. 相似文献
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Ramón Mauricio Coral-Vázquez Juan Fernando Romero Arauz Samuel Canizales-Quinteros Agustín Coronel Elith Yazmin Valencia Villalvazo Jaime Hernández Rivera Belem Ramírez Regalado David Rojano Mejía Patricia Canto 《Clinical biochemistry》2013,46(7-8):627-632
ObjectiveSeveral studies have reported the association of genes related to vascular tone, hypertension, oxidative stress and preeclampsia. We investigated the possible association among three polymorphisms in eNOS (as well their haplotypes): one of MTHFR, one of GSTP1 and one of AGT, with severe preeclampsia in Mexican-Mestizo women.MethodsTwo hundred thirty women with severe preeclampsia and 350 control subjects were genotyped; for rs2070744 and rs1799983 of eNOS, rs1801133 of MTHFR, rs1695 of GSTP1 and rs699 of AGT we used real-time PCR allelic discrimination and for VNTR of eNOS, PCR. Allele frequency differences were assessed by χ2. Logistic regression was used to test for associations and for haplotype frequencies using Haploview 4.2.ResultsGenotypic and allelic distribution of the polymorphisms was similar between cases and controls; likewise, haplotype frequencies of the three polymorphisms of eNOS did not differ significantly.ConclusionsTo our knowledge, this is the first time that these polymorphisms have been analyzed together and exclusively in women with severe preeclampsia. However, we did not find an association between polymorphisms of eNOS, MTHFR, GSTP1 and AGT with severe preeclampsia in our population. Additionally, we observed differences in the distribution of the alleles and genotypes of these polymorphisms in our population in comparison to those described in other ethnic groups. 相似文献
90.
Jose Antonio Moreno Chulilla Maria Soledad Romero Colás Martín Gutiérrez Ma 《World journal of gastroenterology : WJG》2009,15(37):4627-4637
Most anemia is related to the digestive system by dietary deficiency, malabsorption, or chronic bleeding. We review the World Health Organization definition of anemia, its morphological classification (microcytic, macrocytic and normocytic) and pathogenic classification (regenerative and hypo regenerative), and integration of these classifications. Interpretation of laboratory tests is included, from the simplest (blood count, routine biochemistry) to the more specific (iron metabolism, vitamin B12, folic acid, reticulocytes, erythropoietin, bone marrow examination and Schilling test), in the text and various algorithms, we propose a hierarchical and logical way to reach a diagnosis as quickly as possible, by properly managing the medical interview, physical examination, appropriate laboratory tests, bone marrow examination, and other complementary tests. The prevalence is emphasized in all sections so that the gastroenterologist can direct the diagnosis to the most common diseases, although the tables also include rare diseases. Digestive diseases potentially causing anemia have been studied in preference, but other causes of anemia have been included in the text and tables. Primitive hematological diseases that cause anemia are only listed, but are not discussed in depth. The last section is dedicated to simplifying all items discussed above, using practical rules to guide diagnosis and medical care with the greatest economy of resources and time. 相似文献