13 research outputs found
Is it possible to predict the success of non-invasive positive pressure ventilation in acute respiratory failure due to COPD?
AbstractThere is now sufficient evidence that non-invasive positive pressure ventilation (NIPPV) in selected patients with severe hypercapnic acute respiratory failure due to chronic obstructive pulmonary disease (COPD) is more effective than pharmacological therapy alone. The aim of this study was to identify prognostic factors to predict the success of this technique. Fifty-nine consecutive patients with COPD admitted to a respiratory ward for 75 episodes of acute respiratory failure treated with NIPPV were analysed: success (77%) or failure (23%) were evaluated by survival and the need for endotracheal intubation. There were no significant differences in age, sex, cause of relapse and lung function tests between the two groups. Patients in whom NIPPV was unsuccessful were significantly underweight, had an higher Acute Physiology and Chronic Health Evaluation (APACHE) II score, and a lower serum level of albumin in comparison with those in whom NIPPV was successful. They demonstrated significantly greater abnormalities in pH and P a CO2at baseline and after 2 h of NIPPV. The logistic regression analysis demonstrated that, when all the variables were tested together, a high APACHE II score and a low albumin level continued to have a significant predictive effect. This analysis could predict the outcome in 82% of patients. In conclusion, our study suggests that low albumin serum levels and a high APACHE II score may be important indices in predicting the success of NIPPV
TeV-scale seesaw from a multi-Higgs model
We suggest new simple model of generating tiny neutrino masses through a
TeV-scale seesaw mechanism without requiring tiny Yukawa couplings. This model
is a simple extension of the standard model by introducing extra one Higgs
singlet, and one Higgs doublet with a tiny vacuum expectation value.
Experimental constraints, electroweak precision data and no large flavor
changing neutral currents, are satisfied since the extra doublet only has a
Yukawa interaction with lepton doublets and right-handed neutrinos, and their
masses are heavy of order a TeV-scale. Since active light neutrinos are
Majorana particles, this model predicts a neutrinoless double beta decay.Comment: 21 pages, 8 figure
Neutrino oscillation constraints on neutrinoless double beta decay
We have studied the constraints imposed by the results of neutrino
oscillation experiments on the effective Majorana mass || that characterizes
the contribution of Majorana neutrino masses to the matrix element of
neutrinoless double-beta decay. We have shown that in a general scheme with
three Majorana neutrinos and a hierarchy of neutrino masses (which can be
explained by the see-saw mechanism), the results of neutrino oscillation
experiments imply rather strong constraints on the parameter ||. From the
results of the first reactor long-baseline experiment CHOOZ and the Bugey
experiment it follows that || < 3x10^{-2} eV if the largest mass-squared
difference is smaller than 2 eV^2. Hence, we conclude that the observation of
neutrinoless double-beta decay with a probability that corresponds to || >
10^{-1} eV would be a signal for a non-hierarchical neutrino mass spectrum
and/or non-standard mechanisms of lepton number violation.Comment: 20 pages, including 4 figure
Collider aspects of flavour physics at high Q
This review presents flavour related issues in the production and decays of
heavy states at LHC, both from the experimental side and from the theoretical
side. We review top quark physics and discuss flavour aspects of several
extensions of the Standard Model, such as supersymmetry, little Higgs model or
models with extra dimensions. This includes discovery aspects as well as
measurement of several properties of these heavy states. We also present public
available computational tools related to this topic.Comment: Report of Working Group 1 of the CERN Workshop ``Flavour in the era
of the LHC'', Geneva, Switzerland, November 2005 -- March 200
Lamivudine and alpha interferon in combination long term for precore mutant chronic hepatitis B
A comparison interferon and thymosin vs interferon and ribavirin combination therapy in interferon non-responders with chronic hepatitis C
Can Vitamin D deficiency influence muscle performance in postmenopausal women? A multicenter retrospective study
Background: The presence of the vitamin D receptor (VDR) has been recently demonstrated in human muscle supporting the theory of a role of vitamin D in the proliferation and differentiation of muscle cells. So far only few studies investigated the association between vitamin D and muscle performance in postmenopausal women. Aim: To define the functional impact of vitamin D deficiency. Design: Multicenter retrospective study. Setting: Five Italian outpatient services of Physical and Rehabilitation Medicine (PRM). Population: Postmenopausal women. Methods: We divided the population in two groups based on the threshold of 30 ng/mL as cut-off to define sufficient and insufficient serum levels of 25-hydroxyvitamin D3 [25(OH)D3]. Outcome measures were: appendicular lean mass (ALM); ALM-to-BMI ratio (ALMBMI); total fat mass (FM); visceral adipose tissue (VAT); Hand Grip Strength (HGS); Knee Isometric Extension Strength (KES); Short Physical Performance Battery (SPPB); 4-meter gait speed (4MGS). Results: We analyzed the data records of 401 postmenopausal women (mean age 66.93±8.47 years): 203 with hypovitaminosis D (mean age 66.81±8.11 years) and 198 with normal levels of 25(OH)D3 (mean age 67.04±8.84 years). The analysis showed a significant difference between the two groups in terms of: ALMBMI(0.002), FM (P<0.001), VAT mass (0.010), VAT volume (P=0.006), HGS (P<0.001), KES (P<0.001), SPPB score (P<0.001), percentage of people with a 4MGS≤0.8 m/s (P<0.001). Furthermore, there were significant correlations (P<0.001) between serum levels of 25(OH)D3 and HGS (r=0.323), KES (r=0.510), and SPPB sit to stand (r=-0.362) and walking sub-scores (r=-0.312). Conclusions: This multicenter study demonstrated that postmenopausal women with vitamin D deficiency had a significant reduction of appendicular muscle strength and physical performance. Clinical Rehabilitation Impact: This study reported the frequency of hypovitaminosis D in postmenopausal women and its influence on the reduction of muscle mass, strength, and physical performance in a typical population referring to the physiatrist for musculoskeletal disorders.Background: The presence of the vitamin D receptor (VDR) has been recently demonstrated in human muscle supporting the theory of a role of vitamin D in the proliferation and differentiation of muscle cells. So far only few studies investigated the association between vitamin D and muscle performance in postmenopausal women. Aim: To define the functional impact of vitamin D deficiency. Design: Multicenter retrospective study. Setting: Five Italian outpatient services of Physical and Rehabilitation Medicine (PRM). Population: Postmenopausal women. Methods: We divided the population in two groups based on the threshold of 30 ng/mL as cut-off to define sufficient and insufficient serum levels of 25-hydroxyvitamin D3 [25(OH)D3]. Outcome measures were: appendicular lean mass (ALM); ALM-to-BMI ratio (ALMBMI); total fat mass (FM); visceral adipose tissue (VAT); Hand Grip Strength (HGS); Knee Isometric Extension Strength (KES); Short Physical Performance Battery (SPPB); 4-meter gait speed (4MGS). Results: We analyzed the data records of 401 postmenopausal women (mean age 66.93±8.47 years): 203 with hypovitaminosis D (mean age 66.81±8.11 years) and 198 with normal levels of 25(OH)D3 (mean age 67.04±8.84 years). The analysis showed a significant difference between the two groups in terms of: ALMBMI(0.002), FM (P<0.001), VAT mass (0.010), VAT volume (P=0.006), HGS (P<0.001), KES (P<0.001), SPPB score (P<0.001), percentage of people with a 4MGS≤0.8 m/s (P<0.001). Furthermore, there were significant correlations (P<0.001) between serum levels of 25(OH)D3 and HGS (r=0.323), KES (r=0.510), and SPPB sit to stand (r=-0.362) and walking sub-scores (r=-0.312). Conclusions: This multicenter study demonstrated that postmenopausal women with vitamin D deficiency had a significant reduction of appendicular muscle strength and physical performance. Clinical Rehabilitation Impact: This study reported the frequency of hypovitaminosis D in postmenopausal women and its influence on the reduction of muscle mass, strength, and physical performance in a typical population referring to the physiatrist for musculoskeletal disorders
Is it possible to predict the success of non-invasive positive pressure ventilation in acute respiratory failure due to COPD?
Top quark physics at hadron colliders
The top quark, discovered at the FERMILAB TEVATRON collider in 1995, is the heaviest known elementary particle. Today, ten years later, still relatively little is known about its properties. The strong and weak interactions of the top quark are not nearly as well studied as those of the other quarks and leptons. The strong interaction is most directly measured in top quark pair production. The weak interaction is measured in top quark decay and single top quark production, which remains thus far unobserved. The large top-quark mass of about 175 GeV/c2 suggests that it may play a special role in nature. It behaves differently from all other quarks due to its large mass and its correspondingly short lifetime. The top quark decays before it hadronises, passing its spin information on to its decay products. Therefore, it is possible to measure observables that depend on the top quark spin, providing a unique environment for tests of the Standard Model and for searches for physics beyond the Standard Model. This report summarises the latest measurements and studies of top quark properties and rare decays from the TEVATRON in Run II. With more than 1 fb-1 of luminosity delivered to each experiment, CDF and DO, top quark physics at the TEVATRON is at a turning point from first studies to precision measurements with sensitivity to new physics. An outlook onto top quark physics at the Large Hadron Collider (LHC) at CERN, planned to begin operation in the year 2007, is also given