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1.
J Clin Microbiol ; 61(1): e0140922, 2023 01 26.
Artículo en Inglés | MEDLINE | ID: mdl-36533925

RESUMEN

There has been significant increase in the use of molecular tools for the diagnosis of invasive aspergillosis (IA) and mucormycosis. However, their range of detection may be too limited as species diversity and coinfections are increasing. Here, we aimed to evaluate a molecular workflow based on a new multiplex PCR assay detecting the whole Aspergillus genus and the Mucorales order followed by a species-specific PCR or a DNA-sequencing approach for IA and/or mucormycosis diagnosis and species identification on serum. Performances of the MycoGENIE Aspergillus spp./Mucorales spp. duplex PCR kit were analyzed on a broad range of fungal strains and on sera from high-risk patients prospectively over a 12-month period. The kit allowed the detection of nine Aspergillus species and 10 Mucorales (eight genera) strains assessed. No cross-reactions between the two targets were observed. Sera from 744 patients were prospectively analyzed, including 35 IA, 16 mucormycosis, and four coinfections. Sensitivity varies from 85.7% (18/21) in probable/proven IA to 28.6% (4/14) in COVID-19-associated pulmonary aspergillosis. PCR-positive samples corresponded to 21 A. fumigatus, one A. flavus, and one A. nidulans infections. All the disseminated mucormycosis were positive in serum (14/14), including the four Aspergillus coinfections, but sensitivity fell to 33.3% (2/6) in localized forms. DNA sequencing allowed Mucorales identification in serum in 15 patients. Remarkably, the most frequent species identified was Rhizomucor pusillus (eight cases), whereas it is barely found in fungal culture. This molecular workflow is a promising approach to improve IA and mucormycosis diagnosis and epidemiology.


Asunto(s)
Aspergilosis , COVID-19 , Coinfección , Infecciones Fúngicas Invasoras , Mucorales , Mucormicosis , Humanos , Mucormicosis/diagnóstico , Mucormicosis/microbiología , Reacción en Cadena de la Polimerasa Multiplex , Coinfección/diagnóstico , Flujo de Trabajo , Aspergilosis/diagnóstico , Mucorales/genética , Infecciones Fúngicas Invasoras/diagnóstico , Aspergillus/genética , Análisis de Secuencia de ADN , ADN , ADN de Hongos , Prueba de COVID-19
3.
J Neuroinflammation ; 18(1): 223, 2021 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-34587978

RESUMEN

BACKGROUND: The complex pathophysiology of Alzheimer's disease (AD) hampers the development of effective treatments. Attempts to prevent neurodegeneration in AD have failed so far, highlighting the need for further clarification of the underlying cellular and molecular mechanisms. Neuroinflammation seems to play a crucial role in disease progression, although its specific contribution to AD pathogenesis remains elusive. We have previously shown that the modulation of the endocannabinoid system (ECS) renders beneficial effects in a context of amyloidosis, which triggers neuroinflammation. In the 5xFAD model, the genetic inactivation of the enzyme that degrades anandamide (AEA), the fatty acid amide hydrolase (FAAH), was associated with a significant amelioration of the memory deficit. METHODS: In this work, we use electrophysiology, flow cytometry and molecular analysis to evaluate the cellular and molecular mechanisms underlying the improvement associated to the increased endocannabinoid tone in the 5xFAD mouse- model. RESULTS: We demonstrate that the chronic enhancement of the endocannabinoid tone rescues hippocampal synaptic plasticity in the 5xFAD mouse model. At the CA3-CA1 synapse, both basal synaptic transmission and long-term potentiation (LTP) of synaptic transmission are normalized upon FAAH genetic inactivation, in a CB1 receptor (CB1R)- and TRPV1 receptor-independent manner. Dendritic spine density in CA1 pyramidal neurons, which is notably decreased in 6-month-old 5xFAD animals, is also restored. Importantly, we reveal that the expression of microglial factors linked to phagocytic activity, such as TREM2 and CTSD, and other factors related to amyloid beta clearance and involved in neuron-glia crosstalk, such as complement component C3 and complement receptor C3AR, are specifically upregulated in 5xFAD/FAAH-/- animals. CONCLUSION: In summary, our findings support the therapeutic potential of modulating, rather than suppressing, neuroinflammation in Alzheimer's disease. In our model, the long-term enhancement of the endocannabinoid tone triggered augmented microglial activation and amyloid beta phagocytosis, and a consequent reversal in the neuronal phenotype associated to the disease.


Asunto(s)
Enfermedad de Alzheimer/metabolismo , Amidohidrolasas/deficiencia , Péptidos beta-Amiloides/metabolismo , Plasticidad Neuronal/fisiología , Transmisión Sináptica/fisiología , Enfermedad de Alzheimer/patología , Animales , Modelos Animales de Enfermedad , Humanos , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Fagocitosis/fisiología
4.
Int J Colorectal Dis ; 36(6): 1321-1322, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33452908

RESUMEN

PURPOSE: In Italy, colorectal surgery has been strongly affected with the vast majority (90%) of operations treating benign diseases, with an estimated overall 12-week cancellation rate of 72%. Little is known on how to best manage patients with benign diseases and the consequences this interruption of care will have in post-pandemic times. Proctologic diseases have social, psychological, and healthcare repercussions for their high incidence and great impact on the quality of life. METHODS: We decided to treated 10 urgent cases affected from III- and IV-degree hemorrhoids with 3% polidocanol foam in attempt to reduce hemorrhoidal symptoms while waiting for surgery so called "bridge treatment". RESULTS: During the follow-up no complications were occurred, and all patients had resolution of bleeding and pruritus with a mean VAS of 1 (range, 0-1). CONCLUSIONS: This treatment could reduce the bleeding that is the main symptom from which patients suffer and for which they underwent proctological evaluation and surgery. According to our preliminary experience in the impossibility of accessing the surgery during the COVID-19 pandemic, ST could be considered as the treatment of choice in those patients who are suffering from grade III- and IV-degree hemorrhoids while waiting for surgery.


Asunto(s)
COVID-19 , Hemorroides , Hemorroides/cirugía , Humanos , Italia/epidemiología , Pandemias , Polidocanol , Calidad de Vida , SARS-CoV-2 , Escleroterapia/efectos adversos , Resultado del Tratamiento
5.
Int J Colorectal Dis ; 36(10): 2287-2290, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34046696

RESUMEN

PURPOSE: During the past months, the Italian Government has reduced the restrictions and access to hospitals. Since then, up to 40% of non-traumatic abdominal emergencies have had unusual delayed treatment. Given the rapidly evolving situation and the absence of evidence to support recommendations during the pandemic, it is useful to assess how the current situation is influencing the management of elderly with acute appendicitis. METHODS: Between February 2020 and December 2020, all patients older than 68 years old undergone appendectomy were included. Surgical approach, hospital stay, post-operative complications, radiology reports, and histologic examination were included in the retrospective analysis and compared with a same sample of the same period before the pandemic. RESULTS: Twenty-seven patients underwent appendectomy for acute appendicitis during the pandemic and 34 patients in the pre-outbreak period. Laparoscopic approach was completed in 51.8% of the cases, while conversion to laparotomy in 22.3% of patients and open procedure in the 25.9%, before the pandemic 73.6%, 14.7%, and 11.7%, respectively. During the pandemic, complicated appendicitis occurred in 59.3% of the cases (26.5% before the outbreak). One patient was treated for a pelvic abscess, while no minor complications were detected. No mortality rate was reported, with a mean hospital stay of 5.64 days during the outbreak and 4.21 days before the pandemic. CONCLUSION: Our data highlighted a partial delay in diagnosis in the elderly group, and an increase in complicated appendicitis also demonstrated by the need for conversion to laparotomy.


Asunto(s)
Apendicitis , COVID-19 , Laparoscopía , Anciano , Apendicectomía , Apendicitis/epidemiología , Apendicitis/cirugía , Humanos , Tiempo de Internación , Pandemias , Complicaciones Posoperatorias/epidemiología , Estudios Retrospectivos , SARS-CoV-2
6.
J Neuroinflammation ; 15(1): 158, 2018 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-29793509

RESUMEN

BACKGROUND: Because of their low levels of expression and the inadequacy of current research tools, CB2 cannabinoid receptors (CB2R) have been difficult to study, particularly in the brain. This receptor is especially relevant in the context of neuroinflammation, so novel tools are needed to unveil its pathophysiological role(s). METHODS: We have generated a transgenic mouse model in which the expression of enhanced green fluorescent protein (EGFP) is under the control of the cnr2 gene promoter through the insertion of an Internal Ribosomal Entry Site followed by the EGFP coding region immediately 3' of the cnr2 gene and crossed these mice with mice expressing five familial Alzheimer's disease (AD) mutations (5xFAD). RESULTS: Expression of EGFP in control mice was below the level of detection in all regions of the central nervous system (CNS) that we examined. CB2R-dependent-EGFP expression was detected in the CNS of 3-month-old AD mice in areas of intense inflammation and amyloid deposition; expression was coincident with the appearance of plaques in the cortex, hippocampus, brain stem, and thalamus. The expression of EGFP increased as a function of plaque formation and subsequent microgliosis and was restricted to microglial cells located in close proximity to neuritic plaques. AD mice with CB2R deletion exhibited decreased neuritic plaques with no changes in IL1ß expression. CONCLUSIONS: Using a novel reporter mouse line, we found no evidence for CB2R expression in the healthy CNS but clear up-regulation in the context of amyloid-triggered neuroinflammation. Data from CB2R null mice indicate that they play a complex role in the response to plaque formation.


Asunto(s)
Enfermedad de Alzheimer/patología , Encéfalo/metabolismo , Regulación de la Expresión Génica/genética , Receptor Cannabinoide CB2/metabolismo , Enfermedad de Alzheimer/genética , Péptidos beta-Amiloides/metabolismo , Análisis de Varianza , Animales , Encéfalo/patología , Antígeno CD11b/metabolismo , Proteínas de Unión al Calcio/metabolismo , Modelos Animales de Enfermedad , Citometría de Flujo , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Proteínas de Microfilamentos/metabolismo , Fragmentos de Péptidos/metabolismo , Fosfopiruvato Hidratasa/metabolismo , Placa Amiloide/metabolismo , Placa Amiloide/patología , Receptor Cannabinoide CB2/genética
7.
Nanotechnology ; 29(32): 325201, 2018 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-29767629

RESUMEN

In this paper, we numerically and experimentally demonstrate how to modulate the amplitude and phase of a microwave ring resonator by means of few-layers chemical vapour deposition graphene. In particular, both numerical and experimental results show a modulation of about 10 dB and a 90 degrees-shift (quadrature phase shift) when the graphene sheet-resistance is varied. These findings prove once again that graphene could be efficiently exploited for the dynamically tuning and modulation of microwave devices fostering the realization of (i) innovative beam-steering and beam-forming systems and (ii) graphene-based sensors.

8.
Int J Colorectal Dis ; 33(11): 1583-1588, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29675591

RESUMEN

PURPOSE: Symptomatic rectocele results in obstructed defecation and constipation. Surgical repair may provide symptomatic relief. A variety of surgical procedures have been used in the rectocele repair to enhance anatomical and functional results and to improve long-term outcomes. METHODS: In this prospective study, we treated 25 selected women suffering from simple symptomatic rectocele with transperineal repair using porcine dermal acellular collagen matrix Biomesh (Permacol®). Watson score and SF-36 questionnaire were used to evaluate postoperative outcomes and quality of life. RESULTS: Follow-up ranged from 12 to 24 months, the mean total Watson score was significantly lower than the preoperative score (P < 0.001), and every patient has improved functional outcomes. There were no major intraoperative or postoperative complications. Two cases of urinary infection and 4 patients delayed wound healing were reported. Those patients who were sexually active prior to surgery have not experienced problems with sexual function or dyspareunia. CONCLUSIONS: Despite lack of comparative study in literature, rectocele repair with Permacol® by the transperineal approach seems an effective and safe procedure that avoids some of the complications associated with synthetic mesh use.


Asunto(s)
Perineo/cirugía , Rectocele/cirugía , Derivación y Consulta , Mallas Quirúrgicas , Centros de Atención Terciaria , Adulto , Animales , Femenino , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , Estudios Prospectivos , Sus scrofa
9.
Ultrasound Obstet Gynecol ; 51(4): 453-462, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29055063

RESUMEN

OBJECTIVE: To estimate the increased test success rate and incremental yield of chromosomal microarray analysis (CMA) over conventional karyotyping in detection of pathogenic copy number variants (CNVs) and variants of unknown significance (VOUS) in early pregnancy loss. METHOD: This was a systematic review conducted in accordance with PRISMA criteria. All articles identified in PubMed, Ovid MEDLINE and Web of Science, between January 2000 and April 2017, that described CNVs in early pregnancy losses (up to 20 weeks) were included. Risk differences were pooled to estimate the incremental yield of CMA over karyotyping overall, and after stratification. In addition, test success rate, defined as the proportion of informative results, was compared in series in which CMA and karyotyping were performed concurrently. RESULTS: Twenty-three studies, reporting on 5507 pregnancy losses up to 20 weeks with full data available, met the inclusion criteria for analysis. In the series in which CMA and karyotyping were performed concurrently, CMA showed a significant improvement in success rate, providing informative results in 95% (95% CI, 94-96%) of cases compared with karyotyping in which informative results were provided in 68% (95% CI, 66-70%) of cases. Combined data from reviewed studies revealed that incremental yields of CMA over karyotyping were 2% (95% CI, 1-2%) for pathogenic CNVs and 4% (95% CI, 3-6%) for VOUS. The most common pathogenic CNVs reported were 22q11.21 and 1p36.33 deletion. CONCLUSION: In comparison with conventional karyotyping, CMA provides a significant increase in test success rate and incremental diagnostic yield in early pregnancy loss. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.


Asunto(s)
Aborto Espontáneo/genética , Variaciones en el Número de Copia de ADN/genética , Cariotipificación/estadística & datos numéricos , Análisis por Micromatrices/estadística & datos numéricos , Aborto Espontáneo/epidemiología , Femenino , Humanos , Valor Predictivo de las Pruebas , Diagnóstico Prenatal/métodos
10.
Bull Entomol Res ; 107(6): 791-798, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28382878

RESUMEN

Egg parasitoid rearing on factitious hosts is an important step to reduce costs and increase availability of the biocontrol agent but it requires quality control to achieve success in field conditions. To this end, this study evaluated the quality of Telenomus remus (Hymenoptera: Platygastridae) reared on Corcyra cephalonica (Lepidoptera: Pyralidae) for until 45 generations. In the first bioassay, we evaluated the body size of the laboratory-produced parasitoids. In the second bioassay, flight activity was examined, measuring the percentage of 'flyers', 'walkers' and 'deformed' parasitoids. The third bioassay assessed parasitism on Spodoptera frugiperda (Lepidoptera: Noctuidae) eggs. Our data indicate that the laboratory-reared parasitoid neither lost its ability to fly nor to parasitize S. frugiperda eggs. In conclusion, quality did not decrease significantly during 45 generations, and therefore rearing of T. remus on C. cephalonica as factitious host promises to be successful.


Asunto(s)
Mariposas Nocturnas/parasitología , Control Biológico de Vectores , Avispas/fisiología , Animales , Femenino , Vuelo Animal , Masculino , Óvulo/parasitología , Control de Calidad , Avispas/anatomía & histología
11.
Opt Express ; 24(20): 22788-22795, 2016 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-27828344

RESUMEN

We propose an innovative approach for the realization of a microwave absorber fully transparent in the optical regime. This device is based on the Salisbury screen configuration, which consists of a lossless spacer, sandwiched between two graphene sheets whose sheet resistances are different and properly engineered. Experimental results show that it is possible to achieve near-perfect electromagnetic absorption in the microwave X-band. These findings are fully supported by an analytical approach based on an equivalent circuital model. Engineering and integration of graphene sheets could facilitate the realization of innovative microwave absorbers with additional electromagnetic and optical functionalities that could circumvent some of the major limitations of opaque microwave absorbers.

12.
J Fish Biol ; 89(5): 2434-2448, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27730635

RESUMEN

The lipid composition of somatic and reproductive tissues was determined for female skipjack tuna Katsuwonus pelamis caught in the western Indian Ocean between latitude 10° N and 20° S and longitude 40° and 70° E. The highest total lipid (TL) contents were in the liver and gonads, with white muscle levels approximately three-fold lower. Three lipid classes dominated: triacylglycerols (TAG), sterol esters and wax esters (SE-WE) and phospholipids (PL). Collectively, these accounted for between 70 and 80% of TLs. Changes in lipid concentrations were evaluated over the maturation cycle. Immature fish had the lowest gonad and liver TL levels; concentrations of TL, TAG, SE-WE and PL accumulated from immature to mature (spawning-capable) phase, reflecting sustained vitellogenic activity of the liver and a transfer of lipids to developing oocytes from the onset of vitellogenesis. Gonado-somatic and hepato-somatic indices were positively correlated with each other and positively related to TL in the gonads and liver. Fulton's condition index and lipid concentrations in muscle did not vary significantly over the maturation cycle; fat content in the main storage tissues was undepleted as the ovary developed. Hence, K. pelamis apparently supports reproduction directly from food intake over the breeding season. In the gonads, reserve lipids (SE-WE and TAG) and sterols were related to batch fecundity but this was not the case for somatic and hepatic tissues. These results suggest that K. pelamis utilizes an income breeding strategy.


Asunto(s)
Metabolismo Energético , Metabolismo de los Lípidos , Reproducción , Atún/metabolismo , Animales , Femenino , Fertilidad , Océano Índico , Lípidos , Hígado/metabolismo , Oogénesis , Ovario/metabolismo , Estaciones del Año
13.
Opt Express ; 23(16): 21032-42, 2015 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-26367955

RESUMEN

We investigate graphene-based optical absorbers that exploit guided mode resonances (GMRs) attaining theoretically perfect absorption over a bandwidth of few nanometers (over the visible and near-infrared ranges) with a 40-fold increase of the monolayer graphene absorption. We analyze the influence of the geometrical parameters on the absorption rate and the angular response for oblique incidence. Finally, we experimentally verify the theoretical predictions in a one-dimensional, dielectric grating by placing it near either a metallic or a dielectric mirror, thus achieving very good agreement between numerical predictions and experimental results.

15.
Ultrasound Obstet Gynecol ; 45(2): 205-10, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24706444

RESUMEN

OBJECTIVE: To assess fetal cardiac function in first-trimester trisomy-21 fetuses as compared with fetuses with other aneuploidies, euploid fetuses with cardiac defects or isolated increased nuchal translucency (NT) and controls. METHODS: During a 2.5-year period, NT, ductus venosus (DV) blood flow, diastolic filling time, early filling time, tricuspid flow, tricuspid and mitral valve E/A velocity ratios, left ventricle shortening fraction, left myocardial performance index and fetal heart rate were assessed in fetuses with a crown-rump length between 45 and 84 mm undergoing chorionic villus sampling at our center. Cardiac parameters among study groups were compared with the use of 95% CIs. RESULTS: The study population comprised 28 fetuses with trisomy 21, 25 with other aneuploidies, 94 euploid fetuses with abnormal findings (27 with cardiac defects, 31 with other structural anomalies and 36 with isolated increased NT) and 271 controls. Trisomy-21 fetuses showed signs of diastolic dysfunction such as increased DV pulsatility index and E/A ratios together with a higher prevalence of tricuspid regurgitation. However, no differences were found in euploid fetuses with cardiac defects or isolated increased NT. CONCLUSIONS: No signs of cardiac dysfunction were observed in euploid fetuses with increased NT or cardiac defects, while in trisomy-21 fetuses signs of diastolic dysfunction could be potentially attributed to volume overload.


Asunto(s)
Arritmias Cardíacas/fisiopatología , Síndrome de Down/fisiopatología , Aneuploidia , Arritmias Cardíacas/diagnóstico por imagen , Estudios de Casos y Controles , Largo Cráneo-Cadera , Síndrome de Down/diagnóstico por imagen , Ecocardiografía , Femenino , Frecuencia Cardíaca Fetal , Humanos , Medida de Translucencia Nucal , Embarazo , Primer Trimestre del Embarazo , Estudios Prospectivos , Factores de Riesgo
16.
Ultrasound Obstet Gynecol ; 46(6): 650-8, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25900824

RESUMEN

OBJECTIVE: To estimate the incremental yield of detecting copy number variants (CNVs) by genomic microarray over karyotyping in fetuses with increased nuchal translucency (NT) diagnosed by first-trimester ultrasound. METHODS: This was a systematic review conducted in accordance with PRISMA criteria. We searched PubMed, Ovid MEDLINE and Web of Science for studies published between January 2009 and January 2015 that described CNVs in fetuses with increased NT, usually defined as ≥ 3.5 mm, and normal karyotype. Search terms included: fetal or prenatal, nuchal translucency or cystic hygroma or ultrasound anomaly, array comparative genomic hybridization or copy number variants, with related search terms. Risk differences were pooled to estimate the overall and stratified microarray incremental yield using RevMan. Quality assessment of included studies was performed using the Quality Assessment tool for Diagnostic Accuracy Studies (QUADAS-2) checklist. RESULTS: Seventeen studies met the inclusion criteria for analysis. Meta-analysis indicated an incremental yield of 5.0% (95% CI, 2.0-8.0%) for the detection of CNVs using microarray when pooling results. Stratified analysis of microarray results demonstrated a 4.0% (95% CI, 2.0-7.0%) incremental yield in cases of isolated NT and 7.0% (95% CI, 2.0-12.0%) when other malformations were present. The most common pathogenic CNVs reported were 22q11.2 deletion, 22q11.2 duplication, 10q26.12q26.3 deletion and 12q21q22 deletion. The pooled prevalence for variants of uncertain significance was 1%. CONCLUSION: The use of genomic microarray provides a 5.0% incremental yield of detecting CNVs in fetuses with increased NT and normal karyotype.


Asunto(s)
Desarrollo Fetal/genética , Enfermedades Fetales/genética , Cariotipo , Linfangioma Quístico/genética , Medida de Translucencia Nucal , Análisis de Matrices Tisulares , Anomalías Múltiples , Duplicación Cromosómica , Cromosomas Humanos Par 22 , Hibridación Genómica Comparativa/métodos , Variaciones en el Número de Copia de ADN , Síndrome de DiGeorge , Femenino , Enfermedades Fetales/diagnóstico por imagen , Genómica , Humanos , Cariotipificación , Linfangioma Quístico/diagnóstico por imagen , Medida de Translucencia Nucal/métodos , Embarazo , Primer Trimestre del Embarazo/genética
17.
Opt Express ; 22(25): 31511-9, 2014 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-25607101

RESUMEN

A one-dimensional dielectric grating, based on a simple geometry, is proposed and investigated to enhance light absorption in a monolayer graphene exploiting guided mode resonances. Numerical findings reveal that the optimized configuration is able to absorb up to 60% of the impinging light at normal incidence for both TE and TM polarizations resulting in a theoretical enhancement factor of about 26 with respect to the monolayer graphene absorption (≈2.3%). Experimental results confirm this behavior showing CVD graphene absorbance peaks up to about 40% over narrow bands of a few nanometers. The simple and flexible design points to a way to realize innovative, scalable and easy-to-fabricate graphene-based optical absorbers.

18.
Opt Lett ; 39(14): 4223-6, 2014 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-25121692

RESUMEN

Mesoscopic self-collimation (MSC) in mesoscopic photonic crystals with high reflectivity is exploited to realize a novel high Q-factor cavity by means of mesoscopic PhC planar mirrors. These mirrors efficiently confine a mode inside a planar Fabry-Perot-like cavity, that results from a beam focusing effect that stabilizes the cavity even for small beam sizes, resembling the focusing behavior of curved mirrors. Moreover, they show an improved reflectivity with respect to their standard distributed Bragg reflector counterparts that allows higher compactness. A Q-factor higher than 104 has been achieved for an optimized 5-period-long mirror cavity. The optimization of the Q-factor and the performances in terms of energy storage, field enhancement, and confinement are detailed.

19.
Ultrasound Obstet Gynecol ; 43(5): 520-4, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24006271

RESUMEN

OBJECTIVE: To investigate whether increased nuchal translucency (NT) in fetuses with a crown-rump length (CRL) below 45 mm needs to be re-evaluated at a later stage, or whether the early NT measurement can be used effectively as an aneuploidy marker. METHODS: This was a prospective cohort study including all singleton fetuses with a CRL between 28 and 44 mm, scanned in our center during 2002-2012. The CRL, NT, fetal karyotype (when available) and pregnancy outcome were recorded. NT reference ranges were constructed using the Lambda-Mu-Sigma (LMS) method in non-referred pregnancies after exclusion of chromosomal anomalies. The 95(th) percentile was used to calculate detection rates for chromosomally abnormal fetuses. RESULTS: NT was successfully measured in 643 of 672 fetuses with a CRL of 28-44 mm. Subsequent cytogenetic analysis revealed 11 cases of trisomy 21, 14 cases of trisomy 13 or 18, three cases of monosomy X, three sex trisomies, three triploidies and 12 balanced anomalies. NT was above the 95(th) percentile in 64% of the fetuses with trisomy 21, in 71% with trisomy 13 or 18 and in all three cases of monosomy X. CONCLUSION: NT appears to be useful as a marker for the early detection of fetal trisomies at 9-10 weeks' gestation (28-44 mm CRL).


Asunto(s)
Aneuploidia , Largo Cráneo-Cadera , Medida de Translucencia Nucal , Biomarcadores , Estudios de Cohortes , Femenino , Edad Gestacional , Humanos , Masculino , Edad Materna , Medida de Translucencia Nucal/métodos , Guías de Práctica Clínica como Asunto , Valor Predictivo de las Pruebas , Embarazo , Primer Trimestre del Embarazo , Estudios Prospectivos , Flujo Sanguíneo Regional
20.
Med Intensiva ; 38(9): 575-9, 2014 Dec.
Artículo en Inglés, Español | MEDLINE | ID: mdl-24786750

RESUMEN

Technology and insertion techniques for cardiac temporary internal pacing have experienced a remarkable development over the last few years. Despite this fact, the procedure continues to have potentially fatal associated complications. Temporary internal pacing is indicated for the treatment of bradyarrhythmias or tachyarrhythmias refractory to conventional treatment, or arrhythmias causing cardiovascular or clinical instability of the patient. On the other hand, the indications of temporary cardiac pacing are far less well defined than those of permanent pacing. Since the decision of implementing temporary pacing is complex and delicate, it should always be carefully considered, and over-indication should be avoided. We must base these decisions on robust knowledge of the arrhythmias that may benefit from temporary internal pacing, and should also acquire the habit of considering external temporary pacing among other less aggressive treatments, and to make the best use of new technologies such as echocardiography that add accuracy to the procedure.


Asunto(s)
Arritmias Cardíacas/cirugía , Marcapaso Artificial , Humanos , Marcapaso Artificial/efectos adversos , Implantación de Prótesis/efectos adversos , Implantación de Prótesis/métodos , Factores de Tiempo , Venas
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