Gonadal function changes in healthy, aging men.
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Adult↗
Biomedical subjects
D Conte
Publications and source records attributed to D Conte.
Gallstone disease and related risk factors in patients with Crohn disease: analysis of 330 consecutive cases.
BACKGROUND: The reported prevalence of gallstone disease (GD), defined as current gallstones or previous cholecystectomy for gallstones, in patients with Crohn disease ranges from 13% to 34%. The aim of this study was to characterize the still undefined risk factors of this complication. METHODS: A total of 330 consecutive patients with Crohn disease (189 males and 141 females aged 17-82 years, mean +/- SD age, 41 +/- 14 years) underwent liver ultrasonography. RESULTS: A diagnosis of GD was made in 78 patients (24%), 54 with current gallstones and 24 who had undergone previous cholecystectomy. Its frequency was comparable in males and females (23% vs 25%), but was significantly associated with age (P =.001), being 13%, 36%, and 51% in patients aged 44 years and younger, 45 to 59 years, and 60 years and older, respectively (P =.001). Its prevalence significantly differed according to the site of the disease at diagnosis (P =.02) and was unrelated to disease duration. Gallstone disease was more frequent in patients who had undergone surgery (34% vs 14%; P =.001) and was significantly associated with the number (P =.001) and site of bowel resections (P =.001), increasing from 28% in the patients who had undergone 1 resection to 53% in those having had 2 or more resections (P =.005) and being significantly higher in patients with a resection involving the ileocecal region. Multivariate analysis showed that age; site of disease at diagnosis; and the presence, number, and site of bowel resections were significantly related to GD. CONCLUSIONS: In patients with Crohn disease, the frequency of GD is significantly higher than that reported in the general population with comparable characteristics (z = 5.04, P<.001). Age; site of disease at diagnosis; and the history, number, and site of bowel resections are independently associated with GD.
Adolescent↗
Genes and mechanisms related to RNA interference regulate expression of the small temporal RNAs that control C. elegans developmental timing.
RNAi is a gene-silencing phenomenon triggered by double-stranded (ds) RNA and involves the generation of 21 to 26 nt RNA segments that guide mRNA destruction. In Caenorhabditis elegans, lin-4 and let-7 encode small temporal RNAs (stRNAs) of 22 nt that regulate stage-specific development. Here we show that inactivation of genes related to RNAi pathway genes, a homolog of Drosophila Dicer (dcr-1), and two homologs of rde-1 (alg-1 and alg-2), cause heterochronic phenotypes similar to lin-4 and let-7 mutations. Further we show that dcr-1, alg-1, and alg-2 are necessary for the maturation and activity of the lin-4 and let-7 stRNAs. Our findings suggest that a common processing machinery generates guide RNAs that mediate both RNAi and endogenous gene regulation.
Animals↗
Analysis of circulating tumor DNA in plasma at diagnosis and during follow-up of lung cancer patients.
We evaluated whether the amount of circulating DNA in plasma could discriminate between lung cancer patients and healthy individuals and whether it is related to disease progression, and we analyzed the kinetics of plasma DNA in disease-free, surgically resected patients. Plasma DNA quantification and analysis of microsatellite alterations were performed in a consecutive series of 84 patients with non-small cell lung cancer, who were studied during follow-up, and 43 healthy controls. In patients, the mean values of plasma DNA concentration were higher than in controls even considering stage Ia patients. Sensitivity and specificity estimates were calculated as the area under the receiver operating characteristic curve (AUC-ROC) curve and showed a value of 0.844. Variations in DNA level and in microsatellite changes correlated with the clinical status of 38 patients monitored during follow-up. The data suggest that quantification and molecular characterization of plasma DNA in lung cancer patients are valuable noninvasive diagnostic tools for discriminating patients from unaffected individuals and for detecting early recurrence during follow-up.
Adult↗
Thymocyte-targeted overexpression of xiap transgene disrupts T lymphoid apoptosis and maturation.
The X-linked inhibitor of apoptosis (XIAP) and other members of the inhibitor of apoptosis (IAP) family can suppress apoptosis induced by a diverse variety of triggers. Functional studies done to date have focused on tissue culture models and adenovirus overexpression of XIAP and other IAP proteins. Here we report the phenotype of an engineered transgenic mouse overexpressing a human IAP, as well as assessing the long-term consequence of IAP overexpression. We document the relative protein expression levels of the endogenous mouse homologue to XIAP, mouse inhibitor of apoptosis (MIAP 3), within thymocyte and T cell subpopulations. The consequence of lymphoid-targeted overexpression of XIAP in transgenic mice suggests a physiological role for the endogenous protein, MIAP3. Xiap-transgenic mice accumulated thymocytes and/or T cells in primary and secondary lymphoid tissue, T cell maturation was perturbed, and transgenic thymocytes resisted a variety of apoptotic triggers both in vitro and in vivo. These observations imply a possible key function for the intrinsic cellular inhibitor XIAP in maintaining the homeostasis of the immune system.
Animals↗
"Hepatitic flare", asthenia, peripheral polyneuropathy and diffuse liver steatosis in a hepatitis C virus asymptomatic chronic carrier.
In July 2000, a 62-year-old female, with a ten-year history of chronic hepatitis C virus infection and persistently normal aspartate amino-transferase and alanine aminotransferase levels, presented with asthenia, weight loss, peripheral polyneuropathy and increased levels of aspartate aminotransferase (8 times upper normal limit), alanine aminotransferase (10 times upper normal limit) and gamma glutamyl-transferase (6 times upper normal limit). The ultrasound findings were consistent with massive liver steatosis. The patient had been previously diagnosed elsewhere as having hepatitis C virus-related "hepatitic flare" with neurological involvement related to concomitant mixed type-III cryoglobulinaemia. However intense exposure to trichloroethylene since April 2000 was revealed and liver histology was fully consistent with non-alcoholic steatohepatitis. The pathogenetic role of the solvent was definitely supported by the complete clinical and biochemical remission within six months of trichloroethylene withdrawal.
Asthenia↗
Clinical course of pregnant women with chronic hepatitis C virus infection and risk of mother-to-child hepatitis C virus transmission.
As far as concerns chronic hepatitis C virus infection in pregnant women, different points remain to be elucidated, such as the clinical course, the rate of mother-to-child hepatitis C virus transmission and, in particular, its route and the possible risk factors. This review aimed to analyse current data on the prevalence of chronic hepatitis C virus infection in pregnant women and its relationship with risk factors, the rate of mother-to-child hepatitis C virus transmission and the factors possibly involved, particularly the maternal hepatitis C virus viral load and the human immunodeficiency virus coinfection, and the type of delivery and feeding. Finally, the appropriate timing for HCV-RNA testing in newborns has been reviewed.
Breast Feeding↗
Identification of XAF1 as an antagonist of XIAP anti-Caspase activity.
The inhibitors of apoptosis (IAPs) suppress apoptosis through the inhibition of the caspase cascade and thus are key proteins in the control of cell death. Here we have isolated the protein XIAP-associated factor 1 (XAF1) on the basis of its ability to bind XIAP, a member of the IAP family. XIAP suppresses caspase activation and cell death in vitro, and XAF1 antagonizes these XIAP activities. Expression of XAF1 triggers a redistribution of XIAP from the cytosol to the nucleus. XAF1 is ubiquitously expressed in normal tissues, but is present at low or undetectable levels in many different cancer cell lines. Loss of control over apoptotic signalling is now recognized as a critical event in the development of cancer. Our results indicate that XAF1 may be important in mediating the apoptosis resistance of cancer cells.
Adaptor Proteins, Signal Transducing↗
Reduced serum ceruloplasmin levels in hereditary haemochromatosis.
As ceruloplasmin (Cp) seems to be involved in iron mobilization, serum Cp levels were measured in 35 patients with hereditary haemochromatosis (HH), 12 with acquired iron overload (AIO) and 36 healthy subjects. Cp was lower in HH patients than in controls (P < 0.001); no difference was found between untreated HH patients and those on a phlebotomy programme (P = 0.07) and between the HH patients carrying the normal and the mutated alleles of the HFE gene (P = 0.8). Cp levels in AIO subjects were significantly higher than in HH patients (P < 0.004) and similar to those of controls (P = 0.2). No differences in albumin, alpha1 acid glycoprotein and copper serum levels were observed in the three groups.
Adult↗
Duodenal expression of a putative stimulator of Fe transport and transferrin receptor in anemia and hemochromatosis.
BACKGROUND & AIMS: Stimulator of Fe Transport (SFT) and transferrin receptor (TfR) are proteins involved in iron transport. This study evaluated iron metabolism protein expression in duodenal biopsy specimens from controls and patients with abnormal iron metabolism. METHODS: Twelve controls, 8 patients with iron deficiency anemia, 7 with HFE-related hemochromatosis, and 6 with non-HFE-related iron overload were studied. Immunohistochemistry was performed on duodenal biopsy specimens with anti-TfR and anti-SFT antibodies which recognize a putative stimulator of Fe transport of ~80 kilodaltons. RESULTS: In controls, the putative stimulator of Fe transport was expressed in the middle and distal part of the villi in the subapical cytoplasmatic region. Its expression increased in anemics and, to a lesser degree, in HFE-related hemochromatotics, whereas it was reduced in patients with non-HFE-related iron overload. TfR expression showed a crypt-to-tip gradient in controls, but not in anemics, in whom it was uniformly overexpressed. TfR expression was intermediate in HFE-related hemochromatotics and similar to controls in non-HFE-related iron overload. CONCLUSIONS: Expression of the putative stimulator of Fe transport and TfR increases in iron deficiency. Increased expression of both proteins is present only in HFE-related hemochromatotics suggesting that other factors may be involved in determining non-HFE-related iron overload phenotype.
Adult↗
Increased cancer risk in a cohort of 230 patients with hereditary hemochromatosis in comparison to matched control patients with non-iron-related chronic liver disease.
It has been suggested that excess iron may facilitate the occurrence of cancer. Patients with hereditary hemochromatosis (HH) are at high risk of developing liver cancer, and studies of limited series reported a high frequency of nonhepatic cancers. To verify whether patients with HH are at higher risk of liver cancer and other malignancies as compared with patients with non-iron-related chronic liver disease (CLD), we analyzed the occurrence of neoplasms in 230 patients with HH and 230 with non-iron-related CLD. The patients were matched by sex, age, duration of follow-up (+/-5 years), and severity of liver disease. On enrollment, the following variables were considered: hepatitis B virus (HBV) and hepatitis C virus (HCV) infections, alcohol abuse, smoking, and a family history of cancer (first-degree relatives). The diagnosis of primary cancers was confirmed by histology. During the follow-up, hepatocellular carcinoma (HCC) developed in 49 and 29 patients (all cirrhotic patients) with HH and non-iron-related CLD, respectively, with a relative risk of 1.8 (95% confidence interval [CI] 1.1-2.9); nonhepatic cancers occurred in 20 and 11 patients, respectively, with a relative risk of 1.8 (95% CI 0.8-4). Four patients with HH and 1 with non-iron-related CLD developed 2 different primary cancers during follow-up. The risk of cancer after adjustment for alcohol abuse, smoking, and family history of cancer was 1.9 (95% CI 1.1-3.1) in the patients with HH. In conclusion, patients with HH are at high risk of both liver cancer and other malignancies, which should be carefully sought during follow-up.
Adult↗
Acetylsalicylic acid inhibits the pituitary response to exercise-related stress in humans.
PURPOSE: Prostaglandins (PGs) modulate the activity of the hypothalamus-pituitary axis, and pituitary hormones are largely involved in the physiological responses to exercise. The purpose of this study was to analyze the effects of acetylsalicylic acid (ASA), an inhibitor of PGs synthesis, in the pituitary responses to physical stress in humans. METHODS: Adrenocorticotropin (ACTH), beta-endorphin, cortisol, growth hormone (GH), and prolactin (PRL) responses to exercise were evaluated after administration of either placebo or ASA. Blood samples for hormone evaluations before (-30, -15, and 0 pre) and after (0 post, +15, +30, +45, +60, and +90 min) a 30-min treadmill exercise (75% of .VO(2max)) were taken from 12 male athletes during two exercise trials. One tablet of ASA (800 mg), or placebo, was administered two times daily for 3 d before and on the morning of each exercise-test. RESULTS: The results clearly show that, compared with placebo, ASA ingestion significantly blunted the increased serum ACTH, beta-endorphin, cortisol, and GH levels before exercise (anticipatory response) and was associated with reduced cortisol concentrations after exercise. Furthermore, although no differences in the GH response to exercise were shown, a significantly reduced total PRL response to stress condition was observed after ASA. CONCLUSION: ASA influences ACTH, beta-endorphin, cortisol, GH, and PRL responses to exercise-related stress in humans (preexercise activation/exercise-linked response). Even though it is not possible to exclude direct action for ASA, our data indirectly confirm a role of PGs in these responses. We have to further evaluate the nature of the preexercise endocrine activation and, because of the large use of anti-inflammatory drugs in athletes, whether the interaction between ASA and hormones might positively or negatively influence health status, performance, and/or recovery.
Adrenocorticotropic Hormone↗
The Sgs1 helicase of Saccharomyces cerevisiae inhibits retrotransposition of Ty1 multimeric arrays.
Ty1 retrotransposons in the yeast Saccharomyces cerevisiae are maintained in a genetically competent but transpositionally dormant state. When located in the ribosomal DNA (rDNA) locus, Ty1 elements are transcriptionally silenced by the specialized heterochromatin that inhibits rDNA repeat recombination. In addition, transposition of all Ty1 elements is repressed at multiple posttranscriptional levels. Here, we demonstrate that Sgs1, a RecQ helicase required for genome stability, inhibits the mobility of Ty1 elements by a posttranslational mechanism. Using an assay for the mobility of Ty1 cDNA via integration or homologous recombination, we found that the mobility of both euchromatic and rDNA-Ty1 elements was increased 32- to 79-fold in sgs1Delta mutants. Increased Ty1 mobility was not due to derepression of silent rDNA-Ty1 elements, since deletion of SGS1 reduced the mitotic stability of rDNA-Ty1 elements but did not stimulate their transcription. Furthermore, deletion of SGS1 did not significantly increase the levels of total Ty1 RNA, protein, or cDNA and did not alter the level or specificity of Ty1 integration. Instead, Ty1 cDNA molecules recombined at a high frequency in sgs1Delta mutants, resulting in transposition of heterogeneous Ty1 multimers. Formation of Ty1 multimers required the homologous recombination protein Rad52 but did not involve recombination between Ty1 cDNA and genomic Ty1 elements. Therefore, Ty1 multimers that transpose at a high frequency in sgs1Delta mutants are formed by intermolecular recombination between extrachromosomal Ty1 cDNA molecules before or during integration. Our data provide the first evidence that the host cell promotes retrotransposition of monomeric Ty1 elements by repressing cDNA recombination.
DNA Helicases↗
Renovascular impedance and esophageal varices in patients with Child-Pugh class A cirrhosis.
PURPOSE: To evaluate the frequency of increased renovascular impedance and its relationship with the presence of esophageal varices in patients with Child-Pugh class A cirrhosis without ascites. MATERIALS AND METHODS: The intraparenchymal renal resistive index (RI) (reference value, <0.7) and portal congestive index (ie, the ratio between the portal cross-sectional area and mean flow velocity; reference value, <0.07) were measured by using duplex Doppler ultrasonography in 50 consecutive patients. The frequency of varices was assessed endoscopically. The data were analyzed with the Fisher exact test. RESULTS: The renal RI was consistent with increased impedance (ie, >0.7) in 18 (36%) patients and was normal in 32 (64%). The proportion of patients with varices was significantly higher in the former group: 14 (78%) versus 10 (31%) (P =.002). In detection of the presence of varices, the renal RI was uniformly better than the portal congestive index in terms of sensitivity (58% vs. 48%), specificity (84% vs 54%), and positive (3.60 vs 1.04) and negative (0.50 vs. 0.96) likelihood ratios. RI determination improved the ability to exclude the presence of varices from a basal pretest probability of 52% (26 of 50 patients) to a final one of 69% (22 of 32 patients) and that of predicting the presence of varices from 48% (24 of 50 patients) to 78% (14 of 18 patients). CONCLUSION: A substantial proportion of patients with Child-Pugh class A cirrhosis without ascites have increased renovascular impedance; this significantly correlates with the presence of varices.
Esophageal and Gastric Varices↗
[Role of HDL cholesterol in the prediction of exercise stress test abnormalities in asymptomatic high-risk patients].
The diagnosis of coronary artery disease in asymptomatic patients is useful in order to target therapeutic intervention in the patients at highest risk. Systematic testing of all asymptomatic adults with coronary risk factors is not feasible. The aim of this study, carried out in 950 healthy subjects, was to assess the predictive value of classical risk factors for positive exercise stress tests (EE). All subjects underwent stress testing using the Bruce protocol. Statistical analysis was performed by multiple logistic regression on half the samples, then by CART (Classification and Regression Trees) analysis on all subjects. Age, HDL-cholesterol and interaction between lipid lowering treatment and LDL-cholesterol were significantly correlated (p < 0.05) to a positive exercise stress test. In both groups, treated or untreated by lipid lowering drugs. CART identified HDL-cholesterol (< 0.40 g/l) as a predictive factor for positive stress testing. Subgroups of elderly patients (> or = 60 years) with probabilities of 20 to 28% for a positive stress test were identified. The authors conclude that the diagnosis of coronary artery disease by systematic exercise stress testing is potentially valuable in elderly patients with low HDL-cholesterol values.
Adult↗
Unusual peripheral T cell lymphoma presenting as acute liver failure and reappearing in the liver allograft.
A 25-year-old man presented with fulminant hepatic failure from an unusual peripheral T cell lymphoma involving the liver and spleen without lymphadenopathy. He underwent liver transplantation before establishing a definitive diagnosis and 21 days later, died from liver allograft failure because of recurrent lymphoma. In both the native liver and hepatic allograft, the lymphoma presented as a sparse cytologically atypical malignant infiltrate intermixed with numerous reactive macrophages, which showed marked angio- and epitheliotropism and irregular areas of coagulative necrosis. The malignant cells were CD3+/ granzyme B+/TIA1+/CD8-/CD56-/S100-- with variable staining for beta F1, CD5, and CD7. Multiplex polymerase chain reaction (PCR) showed rearrangement of the T cell receptor gamma chain gene in the native and transplanted liver and spleen. Even in the absence of a mass lesion or lymphadenopathy, peripheral T cell lymphoma should be included in the differential diagnosis of fulminant hepatic failure in young patients who show no evidence of viral or autoimmune diseases.
Adult↗
Redox properties of protein disulfide bond in oxidized thioredoxin and lysozyme: a pulse radiolysis study.
We have studied the one-electron reduction of oxidized Chlamydomonas reinhardtii thioredoxin and compared it to that of hen egg white lysozyme, using CO(2)(*) (-) free radicals as reductants. This comparison shows that the thioredoxin disulfide/thiol redox couple has different properties than that of lysozyme: the disulfide radical pK(a) is much lower (around 5 for small disulfides, 4.62 for lysozyme, <3 for thioredoxin). To get a better understanding of the modulation of the thioredoxin redox properties we have constructed the mutants W35A and D30A. Their reduction by pulse radiolysis indicates that W35 strongly controls both the disulfide radical acidity (the pK(a) in W35A is equal to ca. 4), and the thiol reactivity. Asp30 is also involved in the control of proton transfer to the disulfide free radical. In addition, its removal seems to increase the reduction potential of the thioredoxin thiyl/thiol couple. Overall, the reduction properties of thioredoxin confirm its nature as a unique reductant.
Alanine↗
Increased prevalence of celiac disease in patients with dyspepsia.
BACKGROUND: Although 30% to 40% of patients with celiac disease (CD) (which affects 1 in 200 individuals) have dyspeptic symptoms, there is a lack o data concerning the prevalence of CD in patients with dyspepsia. METHODS: In this prospective series, we enrolled all consecutive outpatients undergoing endoscopy of the upper gastrointestinal tract for dyspepsia at our centers between January and June 1998. The exclusion criteria were age younger than 12 years, workup or follow-up of an already known disease of the gastrointestinal tract, suspected CD, malabsorption, and/or iron-deficiency anemia. RESULTS: Of the 3019 patients who were evaluated, 517 (17%) were eligible for the study. Endoscopic findings suggested CD in 5 cases. Celiac disease was histologically diagnosed in 6 patients (5 women and 1 man; mean age, 31.3 years; age range, 20-46 years), 3 of whom had a normal endoscopic pattern and 3 of whom had an endoscopic pattern that was consistent with CD. In the patients with histologically diagnosed CD, antiendomysium antibody positivity supported the diagnosis. The relative risk for CD was 2.32 (95% confidence interval, 1.06-5.07) in comparison with the general population and higher among females (3.22; 95% confidence interval, 1.37-7.56). CONCLUSIONS: The present results indicate that the prevalence of CD in patients with dyspepsia is twice that of the general population. Thus, serological screening for CD should be considered in the early workup of these patients to allow diagnosis and treatment of an eminently treatable disease.
Adult↗