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1.
Phys Rev Lett ; 131(16): 162701, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37925687

RESUMO

The ^{12}C/^{13}C ratio is a significant indicator of nucleosynthesis and mixing processes during hydrogen burning in stars. Its value mainly depends on the relative rates of the ^{12}C(p,γ)^{13}N and ^{13}C(p,γ)^{14}N reactions. Both reactions have been studied at the Laboratory for Underground Nuclear Astrophysics (LUNA) in Italy down to the lowest energies to date (E_{c.m.}=60 keV) reaching for the first time the high energy tail of hydrogen burning in the shell of giant stars. Our cross sections, obtained with both prompt γ-ray detection and activation measurements, are the most precise to date with overall systematic uncertainties of 7%-8%. Compared with most of the literature, our results are systematically lower, by 25% for the ^{12}C(p,γ)^{13}N reaction and by 30% for ^{13}C(p,γ)^{14}N. We provide the most precise value up to now of 3.6±0.4 in the 20-140 MK range for the lowest possible ^{12}C/^{13}C ratio that can be produced during H burning in giant stars.

3.
Knee Surg Sports Traumatol Arthrosc ; 30(12): 3932-3943, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34518895

RESUMO

PURPOSE: Periprosthetic joint infections (PJIs) represent a devastating consequence of total joint arthroplasty. The European Knee Associates (EKA), the American Association of Hip and Knee Surgeons (AAHKS) International Committee, and the Arthroplasty Society in Asia (ASIA) board members were interested in quantifying differences in arthroplasty surgeons' use of various PJI prevention measures to provide clinical recommendations to reduce PJI incidence. METHODS: A prospective Microsoft Forms online survey was distributed among EKA, AAHKS International Committee, and ASIA members and their affiliated arthroplasty surgeons. The survey consisted of 20 single and multiple response questions focused on PJI prevention strategies at three perioperative periods: preoperatively, intraoperatively, and postoperatively. RESULTS: Three hundred and ninety-four arthroplasty surgeons from 6 different continents completed the survey. Preoperative: (A) PJI Risk Stratification: 40.6% routinely set thresholds (e.g., BMI, HgbA1C) to be met to qualify for surgery, 36.5% only review past medical history; 9.1% use machine learning to personalize PJI risk; (B) BMI limit: 36% no limit; 15.4% BMI < 35; 30.9% BMI < 40; 17.2% BMI < 45; (C) Nutritional status: 55.3% do not screen; among those who screen their patients (44.7%), albumin is the single most used marker (86.3%); (D) Hyperglycemia/Diabetes: 83.3% check this comorbidity; 88.1% use HgbA1C as single best screening test; (E) MRSA nasal colonization: 63.7% do not test; 28.9% test all patients; 7.4% test selectively. Intraoperative: (A) Antibiotic prophylaxis in high-risk patients: 43.4% use single antibiotic for 24 h; 21.3% use double antibiotic for 24 h; 14.2% use single/double antibiotic for 7 days postoperatively; (B) Skin-cleansing: 68.7% at home (45.6% chlorhexidine sponge; 11.9% clippers); (C) Intraoperative skin disinfection: 46.9% single chlorhexidine; 25% double chlorhexidine-povidone-iodine;15.4% single povidone-iodine; (D) Tranexamic acid (TXA) to reduce bleeding/SSI: 96% yes (51% double IV dose, 35.2% single IV dose, 23.6% intra-articular injection); (E) Surgical suction drain: 52% do not use drains; 19.7% use a drain < 24 h; (F) Intra-articular lavage: 64.9% use only saline; 28.1% use dilute povidone-iodine; (G) Antibiotic local delivery to prevent PJI: 82.4% use antibiotic-added cement. Postoperative: (A) Routine monitoring of PJI serologic markers: 42% only in symptomatic patients; 34.2% do not; 20.8% in all patients; (B) Serologic markers to rule in/out PJI: 95.9% CRP; 71% SEDRATE; 60.6% WBC; (C) Synovial fluid test to rule in/out PJI: 79.6% culture/sensitivity; 69.5% WBC count; 31.4% CRP. CONCLUSIONS: This survey demonstrated that notable differences still exist in the application of PJI preventive measures across different geographic areas: Optimizing the patient preoperatively and applying multimodal intraoperative strategies represent newer, clinically relevant steps in the effort to reduce the burden of PJI. More uniform guidelines still need to be produced from international scientific societies in order facilitate a more comprehensive approach to this devastating complication. LEVEL OF EVIDENCE: IV.


Assuntos
Artrite Infecciosa , Artroplastia de Quadril , Infecções Relacionadas à Prótese , Cirurgiões , Humanos , Estados Unidos/epidemiologia , Artroplastia de Quadril/efeitos adversos , Infecções Relacionadas à Prótese/diagnóstico , Infecções Relacionadas à Prótese/epidemiologia , Infecções Relacionadas à Prótese/etiologia , Estudos Prospectivos , Povidona-Iodo , Clorexidina , Biomarcadores , Antibacterianos/uso terapêutico , Estudos Retrospectivos
4.
Phys Rev Lett ; 127(15): 152701, 2021 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-34677992

RESUMO

One of the main neutron sources for the astrophysical s process is the reaction ^{13}C(α,n)^{16}O, taking place in thermally pulsing asymptotic giant branch stars at temperatures around 90 MK. To model the nucleosynthesis during this process the reaction cross section needs to be known in the 150-230 keV energy window (Gamow peak). At these sub-Coulomb energies, cross section direct measurements are severely affected by the low event rate, making us rely on input from indirect methods and extrapolations from higher-energy direct data. This leads to an uncertainty in the cross section at the relevant energies too high to reliably constrain the nuclear physics input to s-process calculations. We present the results from a new deep-underground measurement of ^{13}C(α,n)^{16}O, covering the energy range 230-300 keV, with drastically reduced uncertainties over previous measurements and for the first time providing data directly inside the s-process Gamow peak. Selected stellar models have been computed to estimate the impact of our revised reaction rate. For stars of nearly solar composition, we find sizeable variations of some isotopes, whose production is influenced by the activation of close-by branching points that are sensitive to the neutron density, in particular, the two radioactive nuclei ^{60}Fe and ^{205}Pb, as well as ^{152}Gd.

5.
Sci Total Environ ; 791: 148277, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34119780

RESUMO

Accurate and temporally consistent measurements of light absorbing aerosol (LAA) heating rate (HR) and of its source apportionment (fossil-fuel, FF; biomass-burning, BB) and speciation (black and brown Carbon; BC, BrC) are needed to evaluate LAA short-term climate forcing. For this purpose, wavelength- and time-dependent accurate LAA absorption coefficients are required. HR was experimentally determined and apportioned (sources/species) in the EMEP/ACTRIS/COLOSSAL-2018 winter campaign in Milan (urban-background site). Two Aethalometers (AE31/AE33) were installed together with a MAAP, CPC, OPC, a low volume sampler (PM2.5) and radiation instruments. AE31/AE33 multiple-scattering correction factors (C) were determined using two reference systems for the absorption coefficient: 1) 5-wavelength PP_UniMI with low time resolution (12 h, applied to PM2.5 samples); 2) timely-resolved MAAP data at a single wavelength. Using wavelength- and time-independent C values for the AE31 and AE33 obtained with the same reference device, the total HR showed a consistency (i.e. reproducibility) with average values comparable at 95% probability. However, if different reference devices/approaches are used, i.e. MAAP is chosen as reference instead of a PP_UniMI, the HR can be overestimated by 23-30% factor (by both AE31/AE33). This became more evident focusing on HR apportionment: AE33 data (corrected by a wavelength- and time-independent C) showed higher HRFF (+24 ± 1%) and higher HRBC (+10 ± 1%) than that of AE31. Conversely, HRBB and HRBrC were -28 ± 1% and -29 ± 1% lower for AE33 compared to AE31. These inconsistencies were overcome by introducing a wavelength-dependent Cλ for both AE31 and AE33, or using multi-wavelength apportionment methods, highlighting the need for further studies on the influence of wavelength corrections for HR determination. Finally, the temporally-resolved determination of C resulted in a diurnal cycle of the HR not statistically different whatever the source- speciation- apportionment used.


Assuntos
Poluentes Atmosféricos , Calefação , Aerossóis/análise , Poluentes Atmosféricos/análise , Carbono/análise , Monitoramento Ambiental , Material Particulado , Reprodutibilidade dos Testes
6.
Nature ; 587(7833): 210-213, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33177669

RESUMO

Light elements were produced in the first few minutes of the Universe through a sequence of nuclear reactions known as Big Bang nucleosynthesis (BBN)1,2. Among the light elements produced during BBN1,2, deuterium is an excellent indicator of cosmological parameters because its abundance is highly sensitive to the primordial baryon density and also depends on the number of neutrino species permeating the early Universe. Although astronomical observations of primordial deuterium abundance have reached percent accuracy3, theoretical predictions4-6 based on BBN are hampered by large uncertainties on the cross-section of the deuterium burning D(p,γ)3He reaction. Here we show that our improved cross-sections of this reaction lead to BBN estimates of the baryon density at the 1.6 percent level, in excellent agreement with a recent analysis of the cosmic microwave background7. Improved cross-section data were obtained by exploiting the negligible cosmic-ray background deep underground at the Laboratory for Underground Nuclear Astrophysics (LUNA) of the Laboratori Nazionali del Gran Sasso (Italy)8,9. We bombarded a high-purity deuterium gas target10 with an intense proton beam from the LUNA 400-kilovolt accelerator11 and detected the γ-rays from the nuclear reaction under study with a high-purity germanium detector. Our experimental results settle the most uncertain nuclear physics input to BBN calculations and substantially improve the reliability of using primordial abundances to probe the physics of the early Universe.

7.
Phys Rev Lett ; 121(17): 172701, 2018 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-30411966

RESUMO

The ^{22}Ne(p,γ)^{23}Na reaction, part of the neon-sodium cycle of hydrogen burning, may explain the observed anticorrelation between sodium and oxygen abundances in globular cluster stars. Its rate is controlled by a number of low-energy resonances and a slowly varying nonresonant component. Three new resonances at E_{p}=156.2, 189.5, and 259.7 keV have recently been observed and confirmed. However, significant uncertainty on the reaction rate remains due to the nonresonant process and to two suggested resonances at E_{p}=71 and 105 keV. Here, new ^{22}Ne(p,γ)^{23}Na data with high statistics and low background are reported. Stringent upper limits of 6×10^{-11} and 7×10^{-11} eV (90% confidence level), respectively, are placed on the two suggested resonances. In addition, the off-resonant S factor has been measured at unprecedented low energy, constraining the contributions from a subthreshold resonance and the direct capture process. As a result, at a temperature of 0.1 GK the error bar of the ^{22}Ne(p,γ)^{23}Na rate is now reduced by 3 orders of magnitude.

9.
Phys Rev Lett ; 117(14): 142502, 2016 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-27740778

RESUMO

The ^{17}O(p,α)^{14}N reaction plays a key role in various astrophysical scenarios, from asymptotic giant branch stars to classical novae. It affects the synthesis of rare isotopes such as ^{17}O and ^{18}F, which can provide constraints on astrophysical models. A new direct determination of the E_{R}=64.5 keV resonance strength performed at the Laboratory for Underground Nuclear Astrophysics (LUNA) accelerator has led to the most accurate value to date ωγ=10.0±1.4_{stat}±0.7_{syst} neV, thanks to a significant background reduction underground and generally improved experimental conditions. The (bare) proton partial width of the corresponding state at E_{x}=5672 keV in ^{18}F is Γ_{p}=35±5_{stat}±3_{syst} neV. This width is about a factor of 2 higher than previously estimated, thus leading to a factor of 2 increase in the ^{17}O(p, α)^{14}N reaction rate at astrophysical temperatures relevant to shell hydrogen burning in red giant and asymptotic giant branch stars. The new rate implies lower ^{17}O/^{16}O ratios, with important implications on the interpretation of astrophysical observables from these stars.

10.
Vet Microbiol ; 180(1-2): 161-6, 2015 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-26344040

RESUMO

Yersinia pseudotuberculosis is a pathogen that infects both animals and humans worldwide. The epidemiology of infection caused by Y. pseudotuberculosis is poorly understood; however, its outbreaks have been traced back to a probable source in wildlife. This study aimed to characterise Y. pseudotuberculosis isolates collected from animals with yersiniosis. This study included 90 isolates of Y. pseudotuberculosis collected from different animals with yersiniosis between 1996 and 2013 in Italy. The isolates were tested for antimicrobial susceptibility and were biotyped. Genes associated with virulence plasmid pYV and those encoding O-antigen, high pathogenicity island (HPI), and superantigenic toxin (YPM) were determined by performing PCR. Pulsed-field gel electrophoresis (PFGE) was performed using NotI and SpeI enzymes, and 3 dendrograms were generated. No antibiotic resistance was found. The presence of pYV was shown in 57 out of 90 isolates. Virulence profiles of majority of the isolates indicated that they belonged to O:1a and O:1b serotypes, biotype 1, and genetic type 2. Isolates belonging to O:2a serotype were detected in sheep and cattle and were found to be associated (for the first time) with septicemia in hares. Y. pseudotuberculosis isolates belonging to O:5a and O:12-O13 serotypes were also detected in hares. To our knowledge, this is the first study to detect Y. pseudotuberculosis isolates belonging to the O:12-O13 serotype from a clinical case in Europe. Results of PFGE indicated that it was a reliable method for investigating the genetic relatedness of Y. pseudotuberculosis isolates. Thus, characterisation of Y. pseudotuberculosis infection in animals should be considered a possible tool for the surveillance of pseudotuberculosis.


Assuntos
Yersiniose/veterinária , Yersinia pseudotuberculosis/genética , Animais , Eletroforese em Gel de Campo Pulsado , Humanos , Itália/epidemiologia , Antígenos O/genética , Reação em Cadeia da Polimerase/métodos , Sorotipagem , Superantígenos/genética , Fatores de Tempo , Virulência/genética , Yersiniose/epidemiologia , Yersiniose/microbiologia , Yersinia pseudotuberculosis/classificação , Yersinia pseudotuberculosis/isolamento & purificação
11.
Phys Rev Lett ; 115(25): 252501, 2015 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-26722918

RESUMO

The ^{22}Ne(p,γ)^{23}Na reaction takes part in the neon-sodium cycle of hydrogen burning. This cycle affects the synthesis of the elements between ^{20}Ne and ^{27}Al in asymptotic giant branch stars and novae. The ^{22}Ne(p,γ)^{23}Na reaction rate is very uncertain because of a large number of unobserved resonances lying in the Gamow window. At proton energies below 400 keV, only upper limits exist in the literature for the resonance strengths. Previous reaction rate evaluations differ by large factors. In the present work, the first direct observations of the ^{22}Ne(p,γ)^{23}Na resonances at 156.2, 189.5, and 259.7 keV are reported. Their resonance strengths are derived with 2%-7% uncertainty. In addition, upper limits for three other resonances are greatly reduced. Data are taken using a windowless ^{22}Ne gas target and high-purity germanium detectors at the Laboratory for Underground Nuclear Astrophysics in the Gran Sasso laboratory of the National Institute for Nuclear Physics, Italy, taking advantage of the ultralow background observed deep underground. The new reaction rate is a factor of 20 higher than the recent evaluation at a temperature of 0.1 GK, relevant to nucleosynthesis in asymptotic giant branch stars.

12.
Malariaworld J ; 6: 3, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-38779626

RESUMO

Background: Drug resistance has been one of the main obstacles in the fight against vector-borne infectious diseases. Among these diseases, malaria represents a serious public health challenge, mainly in the tropics, where vector-favourable climates are a crucial factor. Each of the various anti-malarial drugs currently used against this disease, such as quinolones, sulphonamides and artemisinins are inadequate and new strategies are required. Peptides are known to have a huge number of biological effects. Antimicrobial peptides (AMPs) have been proven to be effective against bacterial, fungal and viral infections. This study explored the effect of the peptide 'deltorphin-II' in Plasmodium berghei-infected mice. Materials and Methods: Mean percentage parasitaemia was calculated by studying infected erythrocytes after microscopic examination of 104 erythrocytes from infected mice on days 4, 7, 10, 14 and 21 after infection in all groups. Results. Deltorphin-II shows maximum activity at a dose of 0.8 mg/kg/day from day 4 to day 21. Pre-treatment of infected mice with naltriben abrogates the deltorphin-II-mediated effect. Conclusion: Deltorphin-II inhibits the development of malaria, most probably via activation of the δ2 receptor.

13.
Phys Rev Lett ; 113(4): 042501, 2014 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-25105610

RESUMO

Recent observations of (6)Li in metal poor stars suggest a large production of this isotope during big bang nucleosynthesis (BBN). In standard BBN calculations, the (2)H(α,γ)(6)Li reaction dominates (6)Li production. This reaction has never been measured inside the BBN energy region because its cross section drops exponentially at low energy and because the electric dipole transition is strongly suppressed for the isoscalar particles (2)H and α at energies below the Coulomb barrier. Indirect measurements using the Coulomb dissociation of (6)Li only give upper limits owing to the dominance of nuclear breakup processes. Here, we report on the results of the first measurement of the (2)H(α,γ)(6)Li cross section at big bang energies. The experiment was performed deep underground at the LUNA 400 kV accelerator in Gran Sasso, Italy. The primordial (6)Li/(7)Li isotopic abundance ratio has been determined to be (1.5 ± 0.3) × 10(-5), from our experimental data and standard BBN theory. The much higher (6)Li/(7)Li values reported for halo stars will likely require a nonstandard physics explanation, as discussed in the literature.

14.
NeuroRehabilitation ; 33(4): 523-30, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24037096

RESUMO

BACKGROUND: Robotic rehabilitation devices for upper limb function (ULF) provide global indicators of a patient's ability, but the temporal evolution of motion related to motor control is disregarded. OBJECTIVE: To determine normative values for indices of accuracy, speed and smoothness in the evaluation of upper limb function. METHODS: Twenty-five healthy individuals performed the Armeo®Spring device "Vertical Capture" task. Custom stand-alone software was developed to provide the following indices: global Hand Path Ratio (HPR), local HPR in the target area (locHPR), vertical and horizontal overshoot (vertOS, horOS), maximum and mean velocity (maxVel, meanVel), mean/maximum velocity, number of peaks in velocity profiles (NVelPeaks) and normalized jerk (NormJerk). The dependence of indices on task characteristics was analyzed by an ANCOVA test. Indices inner relationships were assessed by a correlation and a factor analysis. Normative values were then provided. RESULTS: 4,268 single reaching movements were analyzed. Four indices were not affected by movement direction. Indices were minimally influenced by the difficulty level. Based upon correlation and factor analysis indices and can be grouped into three assessment fields, dealing with precision, velocity and smoothness. CONCLUSIONS: We have developed a tool to assess ULF in dynamic condition. Normative values were obtained to be used as references in assessing patients.


Assuntos
Movimento/fisiologia , Desempenho Psicomotor/fisiologia , Robótica/instrumentação , Extremidade Superior/fisiologia , Adulto , Idoso , Fenômenos Biomecânicos , Análise Fatorial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Adulto Jovem
15.
Perfusion ; 28(4): 298-305, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23411504

RESUMO

Hemostasis is impaired during CABG and coagulation abnormalities often result in clinically relevant organ dysfunctions, eventually increasing morbidity and mortality rates. Fifteen consecutive patients with coronary artery disease submitted to conventional extracorporeal circulation (cECC) have been compared with 15 matched patients, using mini-ECC (MECC). Postoperative lung function was evaluated according to gas exchange, intubation time and lung injury score. In the MECC group, thrombin-antithrombin complex levels (TaTc), prothrombin fragments (PF1+2) formation and thromboelastography (TEG) clotting times were lower compared to the cECC group (p=0.002 and p<0.001, respectively) whereas postoperative blood loss was higher in the cECC group (p=0.030) and more patients required blood transfusion (p=0.020). In the MECC group, postoperative gas exchange values were better, intubation time shorter and lung injury score lower (p<0.001 for all comparisons). Our study suggests that MECC induces less coagulation disorders, leading to lower postoperative blood loss and better postoperative lung function. This approach may be advantageous in high-risk patients.


Assuntos
Coagulação Sanguínea , Ponte de Artéria Coronária/efeitos adversos , Ponte de Artéria Coronária/instrumentação , Circulação Extracorpórea/efeitos adversos , Circulação Extracorpórea/instrumentação , Pulmão/fisiopatologia , Idoso , Feminino , Humanos , Pulmão/fisiologia , Masculino , Pessoa de Meia-Idade , Tromboelastografia
16.
Eur J Clin Microbiol Infect Dis ; 32(4): 531-4, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23132688

RESUMO

In this paper, we report an investigation on cat-scratch disease (CSD) in Northern Italy. Seventy-four cases of CSD were diagnosed at the San Matteo hospital, Pavia, during the period 2005-2010. Of these 74 patients, 18 (24.3 %) reported atypical clinical manifestations such as ocular papillitis, maculopapular eruptions, vertebral infection, pulmonary infiltrates, and granulomatous hepatitis. Contact with cats was documented for 61 patients (82.4 %), while cat-related trauma was reported for 49 patients (66.2 %). We subsequently investigated the presence of Bartonella infection in cats belonging to the above patients and in other domestic and stray cats from three provinces of Northern Italy. Among the 27 domestic cats tested, nine of the 11 belonging to the CSD patients and two of the remaining 16 were infected by B. henselae (81.8 % vs. 12.5 %). Out of over 1,300 stray cats examined, 23.1 % were seropositive for B. henselae; after culturing and genotyping, 17 % were found to be infected by B. henselae (15.5 %) or B. clarridgeiae (1.5 %).


Assuntos
Infecções por Bartonella/epidemiologia , Infecções por Bartonella/veterinária , Bartonella/isolamento & purificação , Doenças do Gato/epidemiologia , Doenças do Gato/transmissão , Adolescente , Adulto , Idoso , Animais , Bartonella/classificação , Bartonella/genética , Infecções por Bartonella/microbiologia , Infecções por Bartonella/patologia , Doenças do Gato/patologia , Gatos , Criança , Pré-Escolar , Feminino , Humanos , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Adulto Jovem
17.
Phys Rev Lett ; 109(20): 202501, 2012 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-23215474

RESUMO

Classical novae are important contributors to the abundances of key isotopes, such as the radioactive (18)F, whose observation by satellite missions could provide constraints on nucleosynthesis models in novae. The (17)O(p,γ)(18)F reaction plays a critical role in the synthesis of both oxygen and fluorine isotopes, but its reaction rate is not well determined because of the lack of experimental data at energies relevant to novae explosions. In this study, the reaction cross section has been measured directly for the first time in a wide energy range E(c.m.)~/= 200-370 keV appropriate to hydrogen burning in classical novae. In addition, the E(c.m.)=183 keV resonance strength, ωγ=1.67±0.12 µeV, has been measured with the highest precision to date. The uncertainty on the (17)O(p,γ)(18)F reaction rate has been reduced by a factor of 4, thus leading to firmer constraints on accurate models of novae nucleosynthesis.

18.
Cerebrovasc Dis ; 34(4): 290-6, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23128470

RESUMO

Intima-media thickness (IMT) provides a surrogate end point of cardiovascular outcomes in clinical trials evaluating the efficacy of cardiovascular risk factor modification. Carotid artery plaque further adds to the cardiovascular risk assessment. It is defined as a focal structure that encroaches into the arterial lumen of at least 0.5 mm or 50% of the surrounding IMT value or demonstrates a thickness >1.5 mm as measured from the media-adventitia interface to the intima-lumen interface. The scientific basis for use of IMT in clinical trials and practice includes ultrasound physics, technical and disease-related principles as well as best practice on the performance, interpretation and documentation of study results. Comparison of IMT results obtained from epidemiological and interventional studies around the world relies on harmonization on approaches to carotid image acquisition and analysis. This updated consensus document delineates further criteria to distinguish early atherosclerotic plaque formation from thickening of IMT. Standardized methods will foster homogenous data collection and analysis, improve the power of randomized clinical trials incorporating IMT and plaque measurements and facilitate the merging of large databases for meta-analyses. IMT results are applied to individual patients as an integrated assessment of cardiovascular risk factors. However, this document recommends against serial monitoring in individual patients.


Assuntos
Artérias Carótidas/patologia , Espessura Intima-Media Carotídea , Acidente Vascular Cerebral/patologia , Doenças Cardiovasculares/diagnóstico por imagem , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/patologia , Artérias Carótidas/diagnóstico por imagem , Humanos , Placa Aterosclerótica/diagnóstico , Placa Aterosclerótica/diagnóstico por imagem , Ensaios Clínicos Controlados Aleatórios como Assunto , Medição de Risco , Fatores de Risco , Acidente Vascular Cerebral/diagnóstico por imagem
19.
Cerebrovasc Dis ; 31(3): 300-4, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21212660

RESUMO

Carotid thickening and plaque detected by B-mode imaging ultrasound are useful to improve the ischemic risk evaluation in asymptomatic subjects over and beyond the traditional cardiovascular risk factors. Some plaque's echographic parameters help describing the vascular risk. We hypothesized that the stenosis degree, plaque surface irregularity, echolucency and texture, compounded in a Total Plaque Risk Score (TPRS), are predictors of the ischemic events in the San Daniele study, a general population-based study of 1,348 subjects followed for 12 years in average. In the 171 subjects with at least one plaque at baseline, high TPRS was the most powerful independent predictor of cerebrovascular events, which occurred in 115 subjects. Addition of plaque characteristics significantly increased the area under the ROC curve (0.90 vs. 0.88, p = 0.04) versus the Framingham risk score alone. The TPRS is a potential new tool to improve the stroke risk prediction.


Assuntos
Estenose das Carótidas/diagnóstico por imagem , Acidente Vascular Cerebral/etiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estenose das Carótidas/complicações , Estenose das Carótidas/mortalidade , Distribuição de Qui-Quadrado , Feminino , Humanos , Itália , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Medição de Risco , Fatores de Risco , Índice de Gravidade de Doença , Acidente Vascular Cerebral/mortalidade , Fatores de Tempo , Ultrassonografia , Adulto Jovem
20.
Minerva Anestesiol ; 76(4): 276-86, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20332741

RESUMO

AIM: Critically ill patients often need catecholamines, but these agents could be associated with an increased risk of death and other adverse cardiac events. Levosimendan is a calcium sensitizer that is able to enhance myocardial contractility without increasing myocardial oxygen use. We conducted a meta-analysis to determine the impact of levosimendan on mortality in critically ill patients. METHODS: Four investigators independently searched BioMedCentral and PubMed to identify all randomized trials that compared levosimendan vs. control with no restriction in dose or time of administration. Exclusion criteria were duplicate publications, non-human experimental studies, and no information on the primary outcome (mortality). RESULTS: Data from a total of 3,350 patients from 27 randomized controlled studies were included in the analysis. Levosimendan was associated with a significant reduction in mortality (333/1893 [17.6%] in the levosimendan group vs. 326/1457 [22.4%] in the control arm, OR=0.74 [0.62-0.89], P for effect=0.001) and in the rate of myocardial infarction (3/493 [0.6%] in the levosimendan group vs. 14/356 [3.9%] in the control arm P=0.007), with a significant increase in the rate of hypotension (164/1484 [11.1%] in the levosimendan group vs. 106/1093 [9.7%] in the control arm P=0.02). CONCLUSION: Levosimendan has cardioprotective effects that could result in a reduced mortality in critically ill patients. A large randomized controlled study is warranted in this setting.


Assuntos
Cardiotônicos/uso terapêutico , Estado Terminal/mortalidade , Estado Terminal/terapia , Hidrazonas/uso terapêutico , Piridazinas/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto , Humanos , Simendana
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