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1.
Prog Urol ; 30(4): 214-218, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31735683

RESUMEN

INTRODUCTION: Nomograms using the VBN model of women micturition allowed evaluating detrusor contractility (k) and urethral obstruction (U) from pressure-flow (PFs) recordings. While the model worked for most of the patients, an intriguing result, negative U value was observed for patients with high flow-low detrusor pressure (Qp voids). To explain that condition, our hypothesis was a weak urethral resistance to dilatation or increased expansibility (URD). METHODS: The area offered to the fluid at each point of the urethra (its dilatation) is a function of the time depending difference between inside and outside pressures. In the VBN model, this function is sigmoid-like, the same for all women. For Qp voids, Qrecorded was more higher than it would be with the recorded pressure (VBN analysis). So, modeling allowed computing abnormally increased urethral wall expansibility (URD) whose consequence would be an increased flow. RESULTS: Among 222 non-neurologic women referred for investigation of various lower urinary tract symptoms, 27 (mean age 66.3±11.4 y) had Qp void: Qmax=27±6mL/s; pdet.Qmax =7.5±4.7cm H2O. Mean URD value was .36±.67. Introduction of URD in a modeled analysis of urodynamic traces led to a good fitting between recorded and computed traces for the 27 Qp. CONCLUSION: Mathematical modeling of micturition allows proposing an explanation of the unexpected observations of Qp voids. They would be due to abnormal urethral wall elasticity. Despite major challenges measurement of this elasticity would be the next step. LEVEL OF EVIDENCE: 3.


Asunto(s)
Síntomas del Sistema Urinario Inferior/fisiopatología , Modelos Teóricos , Uretra/fisiopatología , Obstrucción Uretral/fisiopatología , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Persona de Mediana Edad , Contracción Muscular/fisiología , Nomogramas , Presión , Estudios Retrospectivos , Vejiga Urinaria/metabolismo , Micción , Urodinámica
2.
Prog Urol ; 30(7): 396-401, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31866143

RESUMEN

AIMS: To compare 3 detrusor contractility indices, projected isovolumetric pressure (PIP-BCI), PIP1, and k from the VBN mathematical model, for women referred for evaluation of various lower urinary tract symptoms (LUTS) in relationship to age, presenting complaint and urodynamic diagnosis. METHODS: Urodynamic tracings of non-neurologic women were analyzed. Three indices of detrusor contractility were measured from the pressure-flow study. Exclusion criteria were voided volume<100mL, stage>2 prolapse, interrupted flow, abdominal straining. Age sub-groups were pre-, peri- and post-menopause. Urodynamic diagnosis included incontinence findings and detrusor activity during voiding. RESULTS: Main complaint was incontinence (354 women); 95 women (Other) had non-incontinence LUTS. PIP-BCI, PIP1 and k decreased significantly with ageing in each sub-group. PIP-BCI was significantly different between MUI and Other (P=.0259) while PIP1 was significantly higher in UUI vs. Other (P=.0161) and k in UUI vs. SUI (P=.0107), MUI (P=.0010) and Other (P=.0224). Low value of PIP-BCI for bladder outlet obstruction vs. detrusor overactivity while PIP1 and k values were high and similar for these two diagnoses and a high value of PIP-BCI for detrusor overactivity with impaired contractility close to the value for bladder outlet obstruction while PIP1 and k were low. CONCLUSION: Evaluation of detrusor contractility in women is easily obtained using indices PIP-BCI and PIP1 or using the VBN nomogram giving indice-parameter k. PIP1 and parameter k produced comparable and consistent results with the urodynamic diagnosis while PIP-BCI leads to inconsistencies. LEVEL OF EVIDENCE: 4.


Asunto(s)
Síntomas del Sistema Urinario Inferior/fisiopatología , Contracción Muscular , Vejiga Urinaria/fisiopatología , Incontinencia Urinaria/fisiopatología , Urodinámica , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Persona de Mediana Edad , Estudios Retrospectivos , Adulto Joven
3.
Prog Urol ; 29(11): 567-571, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31473103

RESUMEN

AIMS: The aims of the study were to evaluate the reproducibility of bladder voiding efficiency (BVE) between free flow (FF) and intubated flow(IF) in old women, and to search for a relationship of this index with complaint and urodynamic diagnosis. METHODS: Urodynamic tracings of non-neurologic women referred for investigation of various lower urinary tract symptoms (LUTS) were analyzed. Urodynamic study included one FF followed by one cystometry and IF. Post void residual volume (PVR) was measured using a Bladder-scan. Exclusion criteria were voided volume<100ml and prolapse of grade>2. RESULTS: One hundred and ninety women met the study criteria. The mean age was 74±6 years [65-96years]. The main complaint was urinary incontinence: stress (26), urge (53) and mixed (56). Forty-four women had various complaints without incontinence. Overall BVE IF (77.6±25.8) was significantly lower than BVE FF (90.4±15.3) (P<.0001). Age sub-groups stratification led similar results. BVE IF was significantly lower than BVE FF in women with incontinence whatever the cause. Urodynamic diagnosis was posed according to the ICS/IUGA recommendations and 2 sub-groups defined according with involvement of detrusor. BVE IF was significantly lower than BVE FF for detrusor dysfunction, except for detrusor overactivity. CONCLUSION: In this large cohort of old non-neurologic women studied urodynamically for a variety of LUTS, BVE is higher when evaluated from a FF whatever age and for complaint of urinary incontinence. In addition, a low BVE value from an IF may suggest a detrusor dysfunction. LEVEL OF EVIDENCE: 4.


Asunto(s)
Síntomas del Sistema Urinario Inferior/fisiopatología , Vejiga Urinaria/fisiología , Micción/fisiología , Urodinámica/fisiología , Factores de Edad , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Estudios Retrospectivos
4.
Phys Rev Lett ; 121(23): 235004, 2018 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-30576190

RESUMEN

Quantitative experiments on the parametric decay instability of near-acoustic plasma waves provide strong evidence that trapped particles reduce the instability threshold below fluid models. At low temperatures, the broad characteristics of the parametric instability are determined by the frequency detuning of the pump and daughter wave, and the wave-wave coupling strength, surprisingly consistent with cold fluid, three-wave theories. However, at higher temperatures, trapped particle effects dominate, and the pump wave becomes unstable at half the threshold pump wave amplitude with similar exponential growth rates as for a cold plasma.

5.
Prog Urol ; 28(4): 230-235, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29307483

RESUMEN

AIMS: Population ageing has as consequence an increasing number of women older than 80 years with lower urinary tract symptoms (LUTS). Despite old age, urodynamic study is often performed to diagnose the cause of LUTS. Our purpose is to discuss the contribution of urodynamics to manage that population. METHODS: Urodynamic studies of 169 consecutive women older than 80 years, respectively 124 non-neurological (non-N) and 45 neurological (N), were retrospectively analysed. RESULTS: Number of co-morbidities was lower in non-N (2.5 vs. 3.1) with predominance of cardiovascular and endocrinology while musculo-skeletal, cognitive and previous pelvic surgery predominated in N. Among main complaint, incomplete retention or dysuria was more frequent in N while incontinence and frequency were predominant in non-N. More frequent urodynamic diagnosis (UD) was "normal" i.e. non contributive (25.0%) and intrinsic sphincter deficiency (ISD=21.7%) in non-N, detrusor overactivity (DO=42.2%) and detrusor underactivity (DU=38.8%) in N. In non-N, there were 94 treatment proposals based on the complaint when UD was "normal" and on UD for DO, DU and ISD. In N, treatment proposals were mainly prompted voiding or self-catheterization based on DU diagnosis. CONCLUSION: Usefulness of urodynamics to manage LUT dysfunction in women older than 80 y is greatly dependent on their neurological status. In non-neurological women this is non debatable but proposed treatment needs to take into account existing co-morbidities. In neurological women the main usefulness is to unmask DU and to propose the best management in order to avoid complete retention. LEVEL OF EVIDENCE: 4.


Asunto(s)
Síntomas del Sistema Urinario Inferior/diagnóstico , Síntomas del Sistema Urinario Inferior/fisiopatología , Trastornos Urinarios/diagnóstico , Trastornos Urinarios/fisiopatología , Urodinámica , Factores de Edad , Anciano de 80 o más Años , Femenino , Humanos , Estudios Retrospectivos
6.
Phys Rev Lett ; 119(20): 205101, 2017 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-29219385

RESUMEN

Plasma turbulence is investigated using unprecedented high-resolution ion velocity distribution measurements by the Magnetospheric Multiscale mission (MMS) in the Earth's magnetosheath. This novel observation of a highly structured particle distribution suggests a cascadelike process in velocity space. Complex velocity space structure is investigated using a three-dimensional Hermite transform, revealing, for the first time in observational data, a power-law distribution of moments. In analogy to hydrodynamics, a Kolmogorov approach leads directly to a range of predictions for this phase-space transport. The scaling theory is found to be in agreement with observations. The combined use of state-of-the-art MMS data sets, novel implementation of a Hermite transform method, and scaling theory of the velocity cascade opens new pathways to the understanding of plasma turbulence and the crucial velocity space features that lead to dissipation in plasmas.

7.
Prog Urol ; 27(4): 261-266, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27426046

RESUMEN

AIMS: Nomograms based on Valentini-Besson-Nelson (VBN) model implying only 3 measurements (filling bladder volume, maximum flow-rate [Qmax] and detrusor pressure at Qmax) were recently developed to evaluate detrusor contractility (k) and urethral obstruction (U) in women. As their algebraic fitting leads to fast evaluations (Excel® software), our aims were applications to populations of non-neurologic women without and with bladder outlet obstruction (BOO). METHODS: The software was applied to measurements obtained during pressure flow studies. Hidden hypothesis of nomograms were no significant contribution of abdominal pressure between onset of flow and Qmax and standard nervous excitations until Qmax. Studied populations were 202 women without symptom suggestive of obstruction and 125 women with proven anatomical urethral obstruction who underwent urodynamic study. RESULTS: For non-obstructed women, a good agreement was found between the values of k and U obtained using nomograms or a complete VBN analysis of the recorded curves. Whatever the obstructive status, there was a good correlation between the value of k and U. Evolution with ageing was similar with higher values of k and U in the BOO group. Curves k(age) and U(age) gave coefficients allowing an age adjustment. The high k value in the detrusor overactive (DO) group was consistent with a similar effect to that of BOO on the detrusor. CONCLUSION: Evaluation of detrusor contractility (k) and urethral obstruction (U) can be obtained from the point of Qmax during pressure-flow study. Evolution with ageing is similar with (higher values) or without BOO. DO also induces an increased detrusor contractility. LEVEL OF EVIDENCE: 4.


Asunto(s)
Contracción Muscular/fisiología , Músculo Liso/fisiopatología , Nomogramas , Obstrucción del Cuello de la Vejiga Urinaria/diagnóstico , Vejiga Urinaria/fisiopatología , Urodinámica/fisiología , Femenino , Humanos , Persona de Mediana Edad
8.
Prog Urol ; 26(7): 425-31, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27118034

RESUMEN

AIMS: We assume that the voiding process in women is governed by the detrusor contractility and a "urethral resistance". The value of these 2 parameters, respectively named k and U in the VBN (Valentini-Besson-Nelson) mathematical model of micturition is deduced from the VBN analysis of pressure-flow recordings (PFs). Our objectives were to search for a correlation between these 2 parameters and clinically relevant variables such as chief complaint, urodynamic diagnosis (UD), and age by decades. METHODS: PFs from 125 non-neurogenic women (mean age 58.0±17.2years [range 20-90years]) were retrospectively analyzed using the VBN model. VBN criteria for inclusion were maximum flow rate>2mL/s, voided volume>100mL, and non-interrupted flow. Evaluated parameters were k (without unit) and U (unit: cm H2O). Standard values were k=1.0 and U=0. RESULTS: VBN parameter ranges were k [0.14-1.55] and U [0.0-73.0cm H2O]. There was a significant correlation between k and U for the whole population (P<0.0001) with k=(.259+0.015*U) (R(2)=0.723) and each chief complaint. For UD, significant difference comparing k and U in phasic detrusor overactivity with intrinsic sphincter deficiency and urodynamic stress incontinence was noted. In sub-groups defined according to decades of age, the values of k and U remained similar in sub-groups for those who are less than 50years old and decreased regularly with ageing. CONCLUSION: The detrusor contractility can be easily evaluated in women; lower than in men, its range is less spread out but also adjusted to compensate a "urethral resistance". Phasic detrusor overactivity and post-menopausal age significantly affect detrusor force value. LEVEL OF EVIDENCE: 3.


Asunto(s)
Contracción Muscular , Músculo Liso/fisiología , Vejiga Urinaria/fisiología , Trastornos Urinarios/fisiopatología , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Envejecimiento , Femenino , Humanos , Persona de Mediana Edad , Estudios Retrospectivos , Urodinámica , Adulto Joven
9.
Prog Urol ; 25(11): 649-54, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26094099

RESUMEN

PURPOSE: Ice Water Test (IWT) is not frequently used today. IWT triggers a non-inhibited involuntary detrusor contraction (NIDC) when the bladder is being filled with cold saline solution. NIDC is unmasked via a segmental reflex loop different from the physiological micturition reflex. Our purpose was to search for usefulness of IWT to expose detrusor overactivity (DO). METHODS: One hundred and seventy-nine IWT performed in patients with overactive bladder syndrome (OAB) and conventional cystometry (CC) non-contributive to diagnosis were retrospectively analyzed. An increase of detrusor pressure of 15cm H2O allowed defining positive IWT (with leakage) or intermediate (without leakage). RESULTS: The population comprised of 131 women (58.2±17.3 years) and 48 men (56.1±15.3 years). Main complaints were mixed or urge incontinence (76/179). Hundred and twenty-four patients had a history of neurological disease. From CC, detrusor behavior was founded uncategorized for 106, normal for 53 patients and underactive for 20. These results did not contribute to diagnose a DO. IWT was positive for 22 patients and intermediate for 20. DO was unmasked by IWT for 42 patients (23.4%) of whom 34 had neurological disease. The positive predictive value was 80.9%, the negative predictive value was 34.3%. CONCLUSION: In patients with OAB syndrome, IWT is contributory to unmask DO when CC is not contributive. Our study underlines the interest to perform IWT when urodynamic diagnosis is unclear.


Asunto(s)
Hielo , Vejiga Urinaria Hiperactiva/diagnóstico , Técnicas de Diagnóstico Urológico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
10.
Anal Bioanal Chem ; 405(2-3): 451-65, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23064705

RESUMEN

This review covers applications of pristine and functionalized single-wall carbon nanotubes (SWCNTs) in nano-medicine, cultural heritage, and biosensors. The physicochemical properties of these engineered nanoparticles are similar to those of ultrafine components of airborne pollution (UF) and might have similar adverse effects. UF may impair cardiovascular autonomic control (inducing a high-risk condition for adverse cardiovascular effects), cause mammalian embryo toxicity, and increase geno-cytotoxic risk. SWCNTs coated with a biopolymer, for example polyethylenimine (PEI), become extremely biocompatible, hence are useful for in-vivo and in-vitro drug delivery and gene transfection. It is also possible to successfully immobilize a human enteric virus on PEI/SWCNT composites, suggesting application as a carrier in non-permissive media. The effectiveness of carbon nanostructured materials in the cleaning, restoration, and consolidation of deteriorated historical surfaces has been widely shown by the use of carbon nanomicelles to remove black dendritic crust from stone surfaces. The nanomicelles, here, have the twofold role of delivery and controlled release of the cleaning agents. The high biocompatibility of functionalized SWCNTs with enzymes and proteins is a fundamental feature used in the assembly of electrochemical biosensors. In particular, a third-generation protoporphyrin IX-based biosensor has been assembled for amperometric detection of nitrite, an environmental pollutant involved in the biodeterioration and black encrustation of historical surfaces.


Asunto(s)
Técnicas Biosensibles/instrumentación , Nanomedicina/instrumentación , Nanoestructuras/química , Animales , Técnicas Biosensibles/métodos , Carbono/química , Humanos , Nanomedicina/métodos , Proteínas/química
11.
Anal Bioanal Chem ; 405(11): 3449-74, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23274557

RESUMEN

In this critical review, new nanomaterials based on graphene (GN) are described, especially those used for the assembly of miniaturized electrochemical transducers. In particular, the physicochemical properties and mechanical features of few layers of graphene (FLGs) are described, as is their use for assembly of chemically modified sensors, biosensors, and immunosensors. The FLGs described here were functionalized by chemical treatment in solution, resulting in oxidized and/or reduced surfaces, edges, and sides. The presence of oxygenated functionality strongly affects the electrocatalysis and the electron-transfer properties of several molecular targets, not only in the solid phase (e.g. in field-effect transistors, FETs) but also in liquid matrices (chemically modified electrodes and biosensors). In addition, "green chemistry" reagents, for example ionic liquids (ILs) can be used for exfoliation and intercalation of graphene planes, to obtain stable and homogeneous nanodispersions. The assembled sensors, biosensors, and immunosensors are extremely useful for electrochemical detection of several electro-active targets of importance in food analysis, environmental monitoring, and clinical diagnosis. A detailed description of each analytical application has been given in this critical review and brief remarks on the emerging disciplines of nanomedicine and nanofoods are also discussed.

12.
J Endocrinol Invest ; 36(8): 550-7, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23324476

RESUMEN

BACKGROUND: Data of the literature demonstrated controversial results of a correlation between transsexualism and genetic mutations. AIM: To evaluate the hormone and gene profile of male-female (M-F) transsexual. SUBJECTS AND METHODS: Thirty M-F transsexuals aged 24-39. Seventeen had already undergone sex reassignment surgery, 13 were awaiting. All subjects had been undergoing estrogen and antiandrogen therapy. We studied hormones of the hypothalamus- pituitary-testicular axis, thyroid and adrenal profile, GH basal and after GHRH stimulation, IGF-I. The gene study analyzed SRY, AR, DAX1, SOX9, AZF region of the Y chromosome. RESULTS: Pre-surgery subjects had elevated PRL, reduced testosterone and gonadotropins. Post-surgery subjects showed reduced androgens, a marked increase in LH and FSH and normal PRL. Cortisol and ACTH were similar to reference values in pre- and post-surgery patients. There was a marked increase in the baseline and post-stimulation GH values in 6 of the 13 pre-surgery patients, peaking at T15. IGF-I was similar to reference values in both groups except for one post-surgery patient, whose level was below the normal range. There were no polymorphisms in the amplified gene region for SOX9, and a single nucleotide synonimous polymorphism for DAX1. No statistically significant differences were seen in the mean of CAG repeats between controls and transsexual subjects. SRY gene was present in all subjects. Qualitative analysis of the AZFa, AZFb, and AZFc regions did not reveal any microdeletions in any subject. CONCLUSIONS: This gender disorder does not seem to be associated with any molecular mutations of some of the main genes involved in sexual differentiation.


Asunto(s)
Transexualidad/genética , Transexualidad/metabolismo , Adulto , Andrógenos , Cromosomas Humanos Y/genética , Hormona Folículo Estimulante/metabolismo , Genes sry/genética , Hormona del Crecimiento , Humanos , Hormona Luteinizante , Masculino , Factor de Transcripción SOX9/genética , Procesos de Determinación del Sexo/genética , Cirugía de Reasignación de Sexo , Testosterona/metabolismo , Hormonas Tiroideas/metabolismo
13.
Med Lav ; 104(5): 351-8, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24180083

RESUMEN

BACKGROUND: Italian law requires an extensive health surveillance of workers after cessation of their employment status in the case of occupational exposure to carcinogens, including asbestos. Nonetheless, Italian law does not specify the timeframe of these clinical checks, nor who has financial and organizational responsibility for this surveillance. A literature search confirmed a lack of consensus around the objectives and methods to follow up workers with past occupational exposure to asbestos. OBJECTIVES: To develop an updated evidence-based methodology for an appropriate health surveillance programme. METHODS: We present an overview of the field experience developed by the Veneto Region from 2000 to 2011, and new studies that could contribute to establishing a national policy for the medical surveillance of workers with past asbestos exposure. RESULTS: There were three specific topics: (1) definition of a reliable method to identify asbestos workers (through multiple sources and procedures that meet current confidentiality regulations); (2) detection of asbestos fibres in biological media (to support the etiological diagnosis of asbestos-related diseases); (3) creation of a national protocol of health surveillance (through the assessment of policies developed by other Regions in this field, and recruiting from these regions a cohort of past-exposed workers: the epidemiological study should offer relevant suggestions for specific surveillance approaches, based on either estimated cumulative asbestos exposure or detection of x-ray patterns of pleural plaques and/or asbestosis). CONCLUSIONS: These studies will support the Regions in setting up health care policies directed at workers with past asbestos exposure.


Asunto(s)
Amianto/efectos adversos , Asbestosis/epidemiología , Exposición Profesional , Vigilancia de la Población , Amianto/análisis , Asbestosis/sangre , Asbestosis/etiología , Biomarcadores , Detección Precoz del Cáncer/economía , Detección Precoz del Cáncer/métodos , Estudios de Seguimiento , Política de Salud , Humanos , Italia , Responsabilidad Legal , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/economía , Neoplasias Pulmonares/epidemiología , Neoplasias Pulmonares/etiología , Neoplasias Pulmonares/prevención & control , Masculino , Mesotelioma/diagnóstico , Mesotelioma/economía , Mesotelioma/epidemiología , Mesotelioma/etiología , Mesotelioma/prevención & control , Persona de Mediana Edad , Fibras Minerales/análisis , Ocupaciones , Osteopontina/sangre , Neoplasias Pleurales/diagnóstico , Neoplasias Pleurales/economía , Neoplasias Pleurales/epidemiología , Neoplasias Pleurales/etiología , Neoplasias Pleurales/prevención & control , Vigilancia de la Población/métodos , Evaluación de Programas y Proyectos de Salud , Reproducibilidad de los Resultados , Pruebas de Función Respiratoria , Jubilación , Estudios Retrospectivos , Fumar
14.
Br J Cancer ; 107(9): 1608-17, 2012 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-22996614

RESUMEN

BACKGROUND: The potential of an increased risk of breast cancer in women with diabetes has been the subject of a great deal of recent research. METHODS: A meta-analysis was undertaken using a random effects model to investigate the association between diabetes and breast cancer risk. RESULTS: Thirty-nine independent risk estimates were available from observational epidemiological studies. The summary relative risk (SRR) for breast cancer in women with diabetes was 1.27 (95% confidence interval (CI), 1.16-1.39) with no evidence of publication bias. Prospective studies showed a lower risk (SRR 1.23 (95% CI, 1.12-1.35)) than retrospective studies (SRR 1.36 (95% CI, 1.13-1.63)). Type 1 diabetes, or diabetes in pre-menopausal women, were not associated with risk of breast cancer (SRR 1.00 (95% CI, 0.74-1.35) and SRR 0.86 (95% CI, 0.66-1.12), respectively). Studies adjusting for body mass index (BMI) showed lower estimates (SRR 1.16 (95% CI, 1.08-1.24)) as compared with those studies that were not adjusted for BMI (SRR 1.33 (95% CI, 1.18-1.51)). CONCLUSION: The risk of breast cancer in women with type 2 diabetes is increased by 27%, a figure that decreased to 16% after adjustment for BMI. No increased risk was seen for women at pre-menopausal ages or with type 1 diabetes.


Asunto(s)
Neoplasias de la Mama/epidemiología , Diabetes Mellitus Tipo 2/epidemiología , Índice de Masa Corporal , Neoplasias de la Mama/etiología , Diabetes Mellitus Tipo 2/complicaciones , Femenino , Humanos , Medición de Riesgo , Factores de Riesgo
15.
Anal Chem ; 84(13): 5823-31, 2012 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-22726213

RESUMEN

Dispersions of graphene oxide (GO) nanoribbons in ionic liquids, ILs (either 1-butyl-3-methylimidazolium chloride (BMIM-Cl-) or 1-butylpyridinium chloride (-Bupy-Cl-)) have been used to assemble modified screen printed electrodes (SPEs). The graphene oxide/ionic liquid dispersions have been morphologically and structurally characterized by the use of several techniques: X-ray photoelectron spectroscopy (XPS), Fourier transform-infrared (FT-IR) spectroscopy, high-resolution-transmission electron microscopy (HR-TEM). The assembled modified SPEs have then been challenged with various compounds and compared to several electro-active targets. In all cases high peak currents were detected, as well as significant potential shifts, especially in the detection of catecholamines and NADH, compared with the bare SPE and the conventional electrodes, such as glassy carbon (GC) and highly oriented pyrolitic graphite (HOPG). This opens the way to the assembly of new types of sensors and biosensors. The enhanced performances observed are attributed to electrocatalytic effects related to the high electrode surface area, to oxygen-assisted electron transfer, as well as to the disordering effect of the ILs, this latter related to the favorable π-π interactions with the ILs and the GO plane.

16.
Phys Rev Lett ; 108(4): 045001, 2012 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-22400851

RESUMEN

Using direct numerical simulations of a hybrid Vlasov-Maxwell model, kinetic processes are investigated in a two-dimensional turbulent plasma. In the turbulent regime, kinetic effects manifest through a deformation of the ion distribution function. These patterns of non-Maxwellian features are concentrated in space nearby regions of strong magnetic activity: the distribution function is modulated by the magnetic topology, and can elongate along or across the local magnetic field. These results open a new path on the study of kinetic processes such as heating, particle acceleration, and temperature anisotropy, commonly observed in astrophysical and laboratory plasmas.

17.
Nanotechnology ; 22(1): 015104, 2011 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-21135464

RESUMEN

Magnetic bio-hybrid porous scaffolds have been synthesized, nucleating nano-apatite in situ on self-assembling collagen, in the presence of magnetite nano-particles. The magnetic phase acted as a sort of cross-linking agent for the collagen, inducing a chemico-physical-mechanical stabilization of the material and allowing us to control the porosity network of the scaffold. Gradients of bio-mineralization and magnetization were also developed for osteochondral application. The good potentiality of the material as a biomedical device, able to offer assistance to bone regeneration through scaffold reloading with specific factors guided by an external magnetic field, has been preliminarily investigated. Up to now the proof of this concept has been realized through in vitro assessments.


Asunto(s)
Regeneración Ósea , Nanopartículas de Magnetita/química , Nanocompuestos/química , Andamios del Tejido/química , Células de la Médula Ósea/citología , Fosfatos de Calcio , Supervivencia Celular , Fenómenos Químicos , Colágeno Tipo I/química , Durapatita/química , Humanos , Microscopía Electrónica , Porosidad , Espectroscopía Infrarroja por Transformada de Fourier , Células Madre/citología , Difracción de Rayos X
18.
Phys Rev Lett ; 104(20): 205002, 2010 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-20867033

RESUMEN

We present the first 2D hybrid-Vlasov simulations of turbulence in the solar wind that describe the evolution of the energy spectra in a range of two decades of wavelengths around the ion inertial scale. Several previous magnetohydrodynamics and particle-in-cell simulations in the range of large (fluid) wavelengths showed a marked anisotropy of the energy spectra in the direction perpendicular to the mean magnetic field. Here we give evidence that the parallel direction can also be a privileged way for turbulence to develop towards short scales, where kinetic effects govern the plasma dynamics.

19.
G Ital Med Lav Ergon ; 32(4 Suppl): 18-21, 2010.
Artículo en Italiano | MEDLINE | ID: mdl-21438207

RESUMEN

The line B1 is a branch of the existing Metro line B in Rome. The route is long about 5 km, is completely underground and involves the construction of four new stations: Annibaliano, Libia /Gondar, Conca d'Oro and Jonio. The line will have a capacity of transport of 24,000 people/hour in each direction. The works started in 2006 involve about 500 workers. The report provides a statistical analysis of the events that occurred in the period 2005/2010 and aims to introduce the starting and management of this study, also on the basis of the "Operating procedures" issued by the acquisition of OSHAS 18001 certification from the agent of Metro B) / R.I.M.A.T.I. This analysis aims to provide to supervisors, to social security institutions and to workers, a usefull analysis tool in the prevention of the monitored events.


Asunto(s)
Accidentes de Trabajo/prevención & control , Accidentes de Trabajo/estadística & datos numéricos , Arquitectura y Construcción de Instituciones de Salud , Salud Laboral , Vías Férreas , Heridas y Lesiones/epidemiología , Heridas y Lesiones/prevención & control , Humanos , Ciudad de Roma
20.
Eur J Vasc Endovasc Surg ; 37(6): 722-7, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19328729

RESUMEN

OBJECTIVES: To evaluate whether contrast ultrasonography can be used to distinguish asymptomatic from symptomatic carotid plaques and provide insight into underlying pathophysiological differences. DESIGN: Contrast carotid ultrasound was performed in both symptomatic and asymptomatic patients referred for carotid endarterectomy. MATERIALS AND METHODS: Of 77 consecutive patients referred for carotid artery evaluation, 64 underwent carotid endarterectomy for asymptomatic cerebrovascular disease and 9 underwent urgent surgery for acute neurological deficits with hemiparesis. The endarterectomy specimens were assessed immunohistologically. RESULTS: In all 9 patients undergoing urgent surgery, contrast ultrasonography showed the accumulation of diffuse microbubble contrast at the base of the carotid plaque. This pattern was observed only in 1/64 of the patients undergoing surgery for asymptomatic carotid disease. Immunohistologically staining of the endarterectomy specimens showed that the area of microbubble contrast at the base of the symptomatic plaques was associated with an increased number of small diameter (20-30 microm) microvessels staining for vascular endothelial growth factor (VEGF). CONCLUSIONS: Contrast carotid ultrasonography may allow the identification of microvessels with neoangiogenesis at the base of carotid plaques, and differentiate symptomatic from asymptomatic plaques.


Asunto(s)
Estenosis Carotídea/diagnóstico por imagen , Trastornos Cerebrovasculares/etiología , Medios de Contraste , Microburbujas , Microvasos/diagnóstico por imagen , Neovascularización Patológica/diagnóstico por imagen , Ultrasonografía Doppler en Color , Ultrasonografía Doppler de Pulso , Anciano , Estenosis Carotídea/complicaciones , Estenosis Carotídea/metabolismo , Estenosis Carotídea/cirugía , Trastornos Cerebrovasculares/diagnóstico por imagen , Trastornos Cerebrovasculares/metabolismo , Trastornos Cerebrovasculares/cirugía , Endarterectomía Carotidea , Femenino , Humanos , Inmunohistoquímica , Masculino , Microvasos/química , Persona de Mediana Edad , Neovascularización Patológica/metabolismo , Neovascularización Patológica/cirugía , Proyectos Piloto , Valor Predictivo de las Pruebas , Regulación hacia Arriba , Factor A de Crecimiento Endotelial Vascular/análisis
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