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J Osborn

Publications and source records attributed to J Osborn.

At least 19 recordsLinked to original sources
PubMed2006

The glucose clamp reveals an association between adiponectin gene polymorphisms and insulin sensitivity in obese subjects.

Results concerning the association of adiponectin gene polymorphisms (single-nucleotide polymorphisms, SNPs) with obesity, type 2 diabetes (T2DM), metabolic disorders and insulin resistance have not lead to definite conclusions. The aim of our study was to investigate a possible association between the -11391G>A and -11377C>G SNPs of adiponectin gene and measure of insulin sensitivity evaluated by the hyperinsulinemic-euglycemic clamp in a group of 'uncomplicated' obese subjects (with no associated comorbidities) (n=99, mean age 35 years) with a history of obesity lasting at least 10 years. The study of uncomplicated obese subjects, free of possible confounding factors that could interfere with insulin sensitivity, such as pharmacological treatment, provides a good model to assess insulin sensitivity per se. We observed that subjects homozygous for the G allele at locus -11391 had lower M (mg/kg min)/fat-free mass (FFM) index and adiponectin levels compared to subjects with GA+AA genotypes (P=0.002 and P=0.03, respectively) and subjects carrying the -11377G variant had lower M (mg/kg min)/FFM index and adiponectin levels compared to noncarriers (P=0.003 and P=0.03, respectively). Our results imply that the two promoter SNPs, -11391G>A and -11377C>G, of the adiponectin gene are associated with a reduced insulin sensitivity evaluated by hyperinsulinemic-euglycemic clamp in obese subjects.

Adiponectin↗
PubMed2006

Gut-associated bacterial microbiota in paediatric patients with inflammatory bowel disease.

BACKGROUND: Clinical and experimental observations in animal models indicate that intestinal commensal bacteria are involved in the initiation and amplification of inflammatory bowel disease (IBD). No paediatric reports are available on intestinal endogenous microflora in IBD. AIMS: To investigate and characterise the predominant composition of the mucosa-associated intestinal microflora in colonoscopic biopsy specimens of paediatric patients with newly diagnosed IBD. METHODS: Mucosa-associated bacteria were quantified and isolated from biopsy specimens of the ileum, caecum and rectum obtained at colonoscopy in 12 patients with Crohn's disease, 7 with ulcerative colitis, 6 with indeterminate colitis, 10 with lymphonodular hyperplasia of the distal ileum and in 7 controls. Isolation and characterisation were carried out by conventional culture techniques for aerobic and facultative-anaerobic microorganisms, and molecular analysis (16S rRNA-based amplification and real-time polymerase chain reaction assays) for the detection of anaerobic bacterial groups or species. RESULTS: A higher number of mucosa-associated aerobic and facultative-anaerobic bacteria were found in biopsy specimens of children with IBD than in controls. An overall decrease in some bacterial species or groups belonging to the normal anaerobic intestinal flora was suggested by molecular approaches; in particular, occurrence of Bacteroides vulgatus was low in Crohn's disease, ulcerative colitis and indeterminate colitis specimens. CONCLUSION: This is the first paediatric report investigating the intestinal mucosa-associated microflora in patients of the IBD spectrum. These results, although limited by the sample size, allow a better understanding of changes in mucosa-associated bacterial flora in these patients, showing either a predominance of some potentially harmful bacterial groups or a decrease in beneficial bacterial species. These data underline the central role of mucosa-adherent bacteria in IBD.

Adolescent↗
PubMed2005

Accuracy of breath tests using low doses of 13C-urea to diagnose Helicobacter pylori infection: a randomised controlled trial.

BACKGROUND: The 13C-urea breath test (UBT) for detecting Helicobacter pylori infection is a non-invasive method based on the organism's urease activity. Since its first description, the method has been extensively modified. However, only the dose of 13C-urea and the measurement equipment are directly related to the cost of the test. AIMS: (1) To assess the diagnostic accuracy before eradication therapy of three UBTs using 25, 15, and 10 mg of 13C-urea, respectively; and (2) to determine diagnostic performance in the post-eradication setting showing the highest values for sensitivity and specificity with the lowest dose of 13C-urea. METHODS: Three hundred consecutive patients were randomised to be tested with one of the three UBTs. All patients underwent upper endoscopy with biopsies. A total of 222 more patients were enrolled to evaluate the second aim. Infected patients were offered treatment and asked to return 4-6 weeks after the end of therapy to perform endoscopic follow up and to carry out 13C-UBT. RESULTS: In the pretreatment setting, 13C-UBT 25 mg had a sensitivity of 100% (95% confidence interval (CI) 91.8-100) and a specificity of 100% (95% CI 93.7-100); 13C-UBT 15 mg had a sensitivity of 96.1% (95% CI 86.8-98.9) and a specificity of 100% (95% CI 92.6-100); and 13C-UBT 10 mg had a sensitivity of 89.1% (95% CI 77-95.3) and a specificity of 100% (95% CI 93.3-100). As the test with the best performance and the lowest dose of 13C-urea was 13C-UBT 15 mg, it was evaluated after treatment, reporting a sensitivity of 100% (95% CI 79.6-100) and a specificity of 98.9% (95% CI 94.3-99.8). DISCUSSION: UBTs using 25 and 15 mg of 13C-urea were both accurate in the diagnosis of H pylori infection in untreated patients. 13C-UBT 15 mg was also accurate for follow up of patients after treatment.

Adult↗
PubMed2005

Semileptonic decays of d mesons in three-flavor lattice QCD.

We present the first three-flavor lattice QCD calculations for D-->pilnu and D-->Klnu semileptonic decays. Simulations are carried out using ensembles of unquenched gauge fields generated by the MILC Collaboration. With an improved staggered action for light quarks, we are able to simulate at light quark masses down to 1/8 of the strange mass. Consequently, the systematic error from the chiral extrapolation is much smaller than in previous calculations with Wilson-type light quarks. Our results for the form factors at q(2)=0 are f(D-->pi)(+)(0)=0.64(3)(6) and f(D-->K)(+)(0)=0.73(3)(7), where the first error is statistical and the second is systematic, added in quadrature. Combining our results with experimental branching ratios, we obtain the Cabibbo-Kobayashi-Maskawa matrix elements |V(cd)|=0.239(10)(24)(20) and |V(cs)|=0.969(39)(94)(24), where the last errors are from experimental uncertainties.

Journal Article↗
PubMed2004

High-precision lattice QCD confronts experiment.

The recently developed Symanzik-improved staggered-quark discretization allows unquenched lattice-QCD simulations with much smaller (and more realistic) quark masses than previously possible. To test this formalism, we compare experiment with a variety of nonperturbative calculations in QCD drawn from a restricted set of "gold-plated" quantities. We find agreement to within statistical and systematic errors of 3% or less. We discuss the implications for phenomenology and, in particular, for heavy-quark physics.

Journal Article↗
PubMed2003

Do antenatal classes benefit the mother and her baby?

OBJECTIVE: To examine the characteristics of women attending antenatal classes and evaluate the effects of these classes on mothers' and babies' health. METHODS: A population-based observational study on care during pregnancy, delivery and in the postnatal period was carried out in 1995-96. A total of 9004 women resident in 13 regions of Italy who delivered in a 4-month period were interviewed. The outcomes studied were attendance at antenatal classes, Cesarean section, bottle feeding, satisfaction with the experience of childbirth, knowledge of contraception, breast feeding and baby care. RESULTS: A total of 2065 (23.0%) women attended antenatal classes. Women without previous children, those with a higher level of education and office workers were more likely to attend classes. Women who attended antenatal classes had a much lower risk of Cesarean section and were about half as likely to bottle feed while in hospital compared with non-attenders. They received better information on contraception, breast feeding and baby care. Women who attended classes and applied the techniques learned were more satisfied with the experience of childbirth. CONCLUSION: Antenatal classes seem to improve women's knowledge and competence. This may provide a defence against the tendency to overmedicalize pregnancy and childbirth.

Adult↗
PubMed2003

Severity of obstetric complications and risk of adult schizophrenia in male patients: a case-control study.

OBJECTIVE: Obstetric complications may be an etiologically important factor in the development of schizophrenia. The aim of this study was to evaluate whether the risk for developing schizophrenia in adult life is increased in individuals with more severe obstetric complications at birth. METHODS: To this end, mothers were interviewed to gather data about obstetric complications. The 'midwife protocol' of Parnas and colleagues was used to quantify the presence and entity of obstetric complications. We studied the frequency distribution and the severity of obstetric complications in 64 male DSM IV schizophrenic patients. The genetic load was reduced by using 81 brothers who were not psychiatric patients as controls. Odds ratios for the effects of obstetric complications, maternal age, birth order and birth weight were calculated using conditional logistic regression. RESULTS: The only factor found to have a significant effect on the risk of schizophrenia was the overall measure of obstetric complications at birth. The history of obstetric complications was higher in schizophrenic patients than in their siblings. CONCLUSION: The results seem to confirm the hypothesis that obstetric complications may contribute to increased vulnerability to the disease, in addition to genetic risk factors.

Adult↗
PubMed2001

Central AT1 and AT2 receptors mediate chronic intracerebroventricular angiotensin II-induced drinking in rats fed high sodium chloride diet from weaning.

Intracerebroventricular (ICV) angiotensin (AIl) administration stimulates central AII receptors to induce water consumption in rats. The aim of this study was to determine the role of brain AT1 and AT2 receptors in mediating chronic ICV AII-induced drinking in rats raised on normal or high sodium chloride diets from weaning. Rats were weaned at 21 days of age and placed on normal or high sodium chloride diet for 10-12 weeks. At adulthood, the animals were instrumented with brain lateral ventricular cannulas and femoral arterial catheters. Low dose chronic central AII infusion (20 ng min(-1)) significantly (P < 0.05) increased water intake in both groups of rats when compared with their respective controls of 24 h artificial cerebrospinal fluid infusions. In a separate group of high sodium fed rats, coinfusion of AII with the AT1 receptor antagonist, losartan (0.25 microg min(-1)) or the AT2 receptor blocker, PD 123319 (0.50 microg min(-1)) blocked chronic ICV AII-induced drinking. Upon reinfusion of AII water intake increased above control. Following the cessation of AII infusions, water intake returned to values not significantly different from control (P > 0.05). In contrast, in the normal sodium fed rats losartan, but not PD 123319, blocked the AII-mediated water intake. The data demonstrate that in high sodium chloride fed rats AII stimulates both central AT1 and AT2 receptors to induce drinking, while in the normal sodium chloride fed rats the peptide activates the drinking response primarily by stimulation of central AT1 receptors.

Angiotensin II↗
PubMed2001

Occurrence and relapse of bleeding from duodenal ulcer: respective roles of acid secretion and Helicobacter pylori infection.

BACKGROUND: Helicobacter pylori infection, gastric acid hypersecretion and NSAID consumption may cause peptic ulcer. AIM: To investigate the respective roles of H. pylori and acid secretion in bleeding duodenal ulcer. PATIENTS AND METHODS: A total of 99 duodenal ulcer patients were referred for evaluation of acid secretion: seven with Zollinger-Ellison Syndrome; 14 with hypersecretory duodenal ulcer, defined by the coexistence of elevated basal acid output and pentagastrin acid output; and 78 duodenal ulcer patients with normal acid output. All non-Zollinger-Ellison Syndrome patients were H. pylori-positive and cured of infection. All patients were followed-up for a 36-month period, to assess the occurrence of bleeding episodes. RESULTS: Twenty-nine patients had at least one bleeding episode in the 4 years before the study. Bleeding was more frequent in males and in patients on NSAIDs. The mean basal acid output was not higher among bleeders. In the 21 patients (14 hypersecretory duodenal ulcer, seven Zollinger-Ellison Syndrome) with basal acid output > 10 meg/h and pentagastrin acid output > 44.5 meg/h, the risk of bleeding was higher (OR 6.5; 95% CI: 2-21). In the follow-up period, three out of 83 (3.3%) non-Zollinger-Ellison Syndrome patients had a H. pylori-negative duodenal ulcer with bleeding. The risk of bleeding after H. pylori cure was not higher in hypersecretory duodenal ulcer patients (P > 0.3), nor among patients with previous bleeding episodes (P > 0.2). CONCLUSIONS: In H. pylori-positive duodenal ulcer patients, the coexistence of elevated basal acid output and pentagastrin acid output leads to a sixfold increase in the risk of bleeding. After H. pylori cure, gastric acid hypersecretion is not a risk factor for bleeding. However, duodenal ulcer recurrence with bleeding may occasionally occur in patients cured of H. pylori, even if acid output is normal.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed2001

Association of DRB1*04-DQB1*0301 haplotype and lack of association of two polymorphic sites at CTLA-4 gene with Hashimoto's thyroiditis in an Italian population.

Hashimoto's thyroiditis (HT) is an autoimmune disease resulting from a complex interaction between genetic and environmental factors. The genetic loci conferring susceptibility need to be still defined. The aim of the present study was to determine whether Cytotoxic T-Lymphocyte-Associated Antigen-4 (CTLA-4), HLA DRB1, and DQB1 genes were associated to HT in an Italian population. We evaluated the allele distribution of the following loci: CTLA-4 exon 1 A49G dimorphism, which resulted in an amino acidic exchange (Thr/Ala) in the leader peptide, CTLA-4 3' microsatellite, HLA DRB1 and DQB1 in 126 patients with HT and in 301 control subjects from an Italian population (Lazio region). CTLA-4 exon 1 A49G dimorphism was typed by Polymerase Chain Reaction and Restriction Fragment Length Polymorphism (PCR-RFLP); CTLA-4 3' microsatellite alleles were defined using a fluorescence-based method. HLA DRB1 and DQB1 alleles were typed using a SSO reverse line blot method and a probeless procedure based on allele group-specific amplification followed by DNA heteroduplex analysis, respectively. Data were initially analyzed by chi2 test or Fisher's exact test. Multiple logistic regression analysis was then applied on factors with significant crude odds ratios and on CTLA-4 exon 1 A49G dimorphism to investigate their independent effects. The two polymorphic sites at CTLA-4 gene did not increase the risk for HT. The distribution of HLA DRB1 and DQB1 alleles did not show any significant difference between patients and controls, however, the DRB1*04-DQB1*0301 haplotype was significantly increased in patients. Other factors that increase the risk of disease were gender and age. Females showed approximately 18 times more risk than males; subjects older than 50 years had an odds ratio of 6.6. These data suggest that these two polymorphic sites at CTLA-4 do not play a major role in the susceptibility of the disease in an Italian population while female gender, age over 50 years, HLA DRB1*04-DQB1*0301 haplotype increase the risk of developing HT.

Alleles↗
PubMed2000

Preprogramming and control activity of bimanual self-paced motor task in Parkinson's disease.

OBJECTIVE: The authors investigated programming (Bereitschaftspotential or BP) and control activity (Skilled Performance Positivity or SPP) of a bimanual, sequential, skilled motor act in off-therapy Parkinson's disease (PD) patients. METHODS: We recorded Movement Related Potentials (MRPs) in 12, non-demented, off-therapy parkinsonian patients and in 17 control subjects who were performing a skilled, time-locked motor act, which was not routine in their everyday life but had to be learned: the Skilled Performance Task (SPT). BP, SPP and correct performances were evaluated in grand average waveforms and in sequential blocks. RESULTS: The analysis of correct performances showed that accuracy in PD patients was significantly lower than in the control group and this accuracy did not improve throughout the blocks. A significantly low level of performances was associated with an increased BP amplitude (P<0.05) and decreased SPP amplitude (P<0.05) in PD patients. CONCLUSION: Our findings suggest that skill motor learning is impaired in non-demented unmedicated PD patients. We discuss the view that PD patients may allocate more attentional resources, as suggested by the increased BP amplitude, the decreased SPP amplitude and the low correct performances, in order to perform a new skilled motor act.

Aged↗
PubMed2000

[Evaluation of the impact of birth preparation courses on the health of the mother and the newborn].

In 1995-96 a knowledge, attitude and practise (KAP) survey on care during pregnancy, delivery and in the post-natal period was carried out by the National Institute of Health in Italy. Of the 9004 women interviewed, 23% have attended antenatal classes (36% in hospitals, 51% in maternal and child health, MCH, clinics and 13% privately). Women attending these classes tend to be well-educated, primigravidae and resident in the North. Women who attend antenatal classes, especially at MCH clinics, have a lower risk of caesarean section (OR = 0.60), of bottle feeding while in hospital (OR = 0.45) and of receiving no information on contraception (OR = 0.31). Women who attend classes and are able to apply the technique learnt have a reduced risk of being dissatisfied with the experience of childbirth (OR = 0.72), whereas the others have an increased risk of dissatisfaction (OR = 1.87).

Adult↗
PubMed1999

Application of SOFA score to trauma patients. Sequential Organ Failure Assessment.

OBJECTIVE: To assess the ability of the SOFA score (Sequential Organ Failure Assessment) to describe the evolution of organ dysfunction/failure in trauma patients over time in intensive care units (ICU). DESIGN: Retrospective analysis of a prospectively collected database. SETTING: 40 ICUs in 16 countries. PATIENTS: All trauma patients admitted to the ICU in May 1995. MAIN OUTCOME MEASURES AND RESULTS: Incidence of dysfunction/failure of different organs during the first 10 days of stay and the relation between the dysfunction, outcome, and length of stay. Included in the SOFA study were 181 trauma patients (140 males and 41 females). The non-survivors were significantly older than the survivors (51 years+/-20 vs 38+/-16 years, p < 0.05) and had a higher global SOFA score on admission (8+/-4 vs 4+/-3, p < 0.05) and throughout the 10-day stay. On admission, the non-survivors had higher scores for respiratory ( > 3 in 47% of non-survivors vs 17% of survivors), cardiovascular ( > 3 in 24% of non-survivors vs 5.7% of survivors), and neurological systems ( > 4 in 41% of non-survivors vs 16% of survivors); although the trend was maintained over the whole study period, the differences were greater during the first 4-5 days. After the first 4 days, only respiratory dysfunction was significantly related to outcome. A higher SOFA score, admission to the ICU from the same hospital, and the presence of infection on admission were the three major variables associated with a longer length of stay in the ICU (additive regression coefficients: 0.85 days for each SOFA point, 4.4 for admission from the same hospital, 7.26 for infection on admission). CONCLUSIONS: The SOFA score can reliably describe organ dysfunction/ failure in trauma patients. Regular and repeated scoring may be helpful for identifying categories of patients at major risk of prolonged ICU stay or death.

APACHE↗
PubMed1998

Changes in the medical profession in Great Britain in the xix century.

The nineteenth century was important for medicine in Britain because the foundations of a united medical profession were laid by the Medical Act of 1858. This established the General Medical Council which had the responsibility of maintaining a list of qualified medical practitioners. This not only protected the public from unknowingly using unqualified medical practitioners, but also created a monopoly of medical practice which was protected by law. In the second half of the century, women started to qualify and be registered. The century also saw the development of effective anaesthetics and the idea that the health of the public could be preserved by legislation. The notion of prevention was born, even though after a further one hundred years, the profession is still dominated by the idea that its responsibility is to cure.

Accreditation↗
PubMed1997

Time to pregnancy and occupation in a group of Italian women.

BACKGROUND: It is estimated that 10-15% of all couples have experienced an infertility problem. The objective of this study was to evaluate the effect of occupation on the time interval between when a couple starts unprotected intercourse and a clinically recognizable pregnancy time to pregnancy (TTP). METHODS: Data from 622 women who successfully delivered in the week preceding the interview were analysed using the Cox proportional hazards regression. Thirty independent variables were included in the full model. RESULTS: Eleven per cent of women had to wait more than one year before conceiving (mean TTP = 6.7 months). The regression analysis showed that the most important determinants of TTP are the age of the woman (rate ratio = 0.44 for age 35+) and her parity (rate ratio = 1.39). TTP also increased significantly with maternal smoking (rate ratio = 0.77), and decreased with coital frequency (rate ratio = 1.24 for > or = 6 per month) and consumption of coffee (rate ratio = 1.29). None of the female occupational exposures has been found to have an independent statistically significant effect, while male occupation in industry and exposure to welding fumes were associated with an increase of TTP (rate ratio = 0.73 and 0.78, respectively). CONCLUSIONS: Female occupational exposures seem to have only a small effect on TTP compared with biological and lifestyle factors. The present data also suggest that work-related factors may have a bigger influence on male fecundity.

Coffee↗
PubMed1997

Differential risk of non-Hodgkin's lymphoma in Italian patients with primary Sjögren's syndrome.

OBJECTIVE: To assess the incidence of non-Hodgkin's lymphoma (NHL) and estimate the relative risk (RR) of developing lymphoproliferative complications in a large population of Italian patients with Sjögren's syndrome (SS) and to ascertain if any difference exists between the north and centre-south of Italy. METHODS: Differential relative risks of NHL were obtained by comparing the number of observed cases with cases identified on the basis of age-sex-time specific incidence rates extracted from regional cancer registries. RESULTS: Among the 331 patients with SS studied, 9 cases of NHL occurred, while no lymphoid malignancy appeared in patients with overlapping connective tissue disease (secondary SS) or in males with primary SS. As the number of NHL cases identified on the basis of the rate in the cancer registries would have been 0.27, the RR is 33.3 (p < 0.001). The incidence rate of NHL in Italian patients with SS is about 5.1/1000 person-years. 5.4/1000 per year in the north of the country and 4.8/1000 per year in the centre-south. The relative risks are, respectively, 34.7 and 32.5. CONCLUSION: Italian patients with primary SS have increased risk of developing NHL. In this group, the absence of a significant difference between the north and the centre-south of Italy contrasts with the higher incidence of NHL in the general population of northern regions and strengthens the direct connection between primary SS and NHL.

Adult↗
PubMed1996

Pulmonary vascular pressure effects by endothelin-1 in normoxia and chronic hypoxia: a longitudinal study.

The role of endothelin (ET)-1 in pulmonary arterial pressure (Ppa) homeostasis and hypoxia-induced pulmonary hypertension was examined. ET-1 was chronically infused (2 and 4 pmol.kg-1.min-1) into the pulmonary circulation of male Sprague-Dawley rats for 3, 7, and 14 days while they were exposed to normoxia or hypobaric hypoxia (inspired O2 fraction 10%). The role of endogenous ET was examined by infusion of ET antiserum (ET-AS; 0.25 and 0.5 microliter.rat-1.h-1; cross-reacting with ET-1, -2, and -3) or the ETA-receptor blocker BQ-123 (10 pmol.kg-1.min-1). ET-1 (4 pmol) increased Ppa at 3 and 7 days in normoxia and hypoxia and was ineffective at 14 days, probably from ETA-receptor downregulation. BQ-123 blunted the hypoxic Ppa rise at all times, confirming a role for ETA receptors. ET-AS (0.5 microliter) was mostly ineffective but exacerbated hypoxic Ppa at 14 days, in contrast to BQ-123, suggesting that a different ET receptor could be involved. ET-1 infusion (2 pmol) caused right ventricular hypertrophy (RVH) in normoxia and exacerbated RVH in hypoxia, whereas BQ-123 and ET-AS (0.25 microliter) reduced hypoxic RVH. In conclusion, endogenous ET-1 plays a role in hypoxia-induced pulmonary hypertension and RVH by augmenting the level of hypoxic response. ET-1 also affects hematocrit and may reduce blood levels of the vasodilator calcitonin gene-related peptide.

Animals↗