Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 170
Filtrar
Más filtros

Tipo del documento
Intervalo de año de publicación
1.
J Therm Biol ; 76: 1-7, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30143283

RESUMEN

Feed intake (FI) level affects body heat production in thermo-neutral pigs; exposure of pigs to heat stress (HS) also increases body temperature (BT). However remains unclear whether the FI level affects the heat production of HS pigs. This study analyzed the effect of FI level on BT of 9 HS pigs (46.3 ±â€¯2.6 kg body weight) implanted with a thermometer set to register the BT at 5-min intervals into the ileum. Pigs were divided in two groups randomly allotted to two FI treatments: high FI (HFI, 1.20 kg/d), and low FI (LFI, 0.96 kg/d), according to a two-period crossover experimental design. Pigs were fed 3-times a day (0600, 1200, and 2200 h), same amount each time (400 g or 320 g). Ambient temperature (AT) ranged from 29.0 to 35.4 °C. The BT of both HFI and LFI pigs followed a similar pattern along a 24-h period, but the BT of HFI pigs was higher than that of LFI pigs (P < 0.05). Postprandial afternoon and evening BT was higher than that after the morning meal (P < 0.05). The postprandial BT increment differed between meal times and AT, but not between FI levels. The BT of HFI and LFI pigs increased up to 0.18 and 0.22 °C, 0.60 and 0.61 °C, and 0.24 and 0.35 °C after the morning, afternoon, and evening meal, respectively, compared with the preprandial BT (P < 0.05). Hence, the dissipation capacity of feeding-related body heat appears to depend on the thermal load of HS pigs before consuming their meals; presumably, the thermal load during 6-h before the morning meal (AT below 32 °C) was lower than before the evening meal (AT above 32 °C). In conclusion, FI level affects the postprandial BT of HS pigs and its magnitude is larger after the evening and afternoon meals. These data suggest that HS pigs may reduce the voluntary FI during the afternoon and evening hours.


Asunto(s)
Temperatura Corporal , Ingestión de Alimentos , Respuesta al Choque Térmico , Sus scrofa/fisiología , Alimentación Animal , Animales , Regulación de la Temperatura Corporal , Periodo Posprandial , Temperatura
2.
J Anim Physiol Anim Nutr (Berl) ; 102(2): e718-e725, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28990262

RESUMEN

Feed intake and diet composition appear to affect the body temperature of pigs. Two trials were conducted to analyse the effect of feed intake level and dietary protein content on the intestinal temperature (IT) of pigs housed under thermo neutral conditions. Ten pigs (64.1 ± 1.3 kg initial body weight) fitted with an ileal cannula were used. A thermometer set to register the IT at 5-min intervals was implanted into the ileum through the cannula. In both trials, the ambient temperature ranged from 19.1 to 21.6°C and the pigs were fed at 07:00 and 19:00 hr (same amount each time). In trial 1, the pigs were fed daily 1.2 or 1.8 kg of a wheat-soybean meal diet. The IT followed a similar pattern along a 24-hr period regardless the feed intake level. The IT rapidly increased up to 0.61 and 0.74°C after the morning meal and up to 0.53 and 0.47°C after the evening meal in pigs fed 1.2 and 1.8 kg/d respectively. The postprandial IT was higher in pigs fed 1.8 kg after each meal (p < .05). In trial 2, pigs were fed daily 1.8 kg of a low (11%) or a high (22%) crude protein diet. The IT followed a similar pattern along the 24-hr period regardless the dietary protein level. The postprandial IT did not differ between pigs fed the low protein or the high protein (p > .10). The IT rapidly increased up to 0.66 and 0.62°C after the morning meal in pigs fed the high- and low-protein diet (p < .05), but there was no change after the evening meal (p > .10). In conclusion, the feed intake level affected the IT of pigs housed under TN conditions, but the dietary protein content had no effect.


Asunto(s)
Temperatura Corporal/efectos de los fármacos , Proteínas en la Dieta/farmacología , Ingestión de Alimentos/fisiología , Porcinos/fisiología , Alimentación Animal , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Composición Corporal , Dieta/veterinaria , Digestión , Metabolismo Energético , Ambiente , Vivienda para Animales , Masculino
3.
Opt Express ; 25(10): 11254-11264, 2017 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-28788807

RESUMEN

We experimentally demonstrate ultrahigh extinction ratio (>65 dB) amplitude modulators (AMs) that can be electrically tuned to operate across a broad spectral range of 160 nm from 1480 - 1640 nm and 95 nm from 1280 - 1375 nm. Our on-chip AMs employ one extra coupler compared with conventional Mach-Zehnder interferometers (MZI), thus form a cascaded MZI (CMZI) structure. Either directional or adiabatic couplers are used to compose the CMZI AMs and experimental comparisons are made between these two different structures. We investigate the performance of CMZI AMs under extreme conditions such as using 95:5 split ratio couplers and unbalanced waveguide losses. Electro-optic phase shifters are also integrated in the CMZI AMs for high-speed operation. Finally, we investigate the output optical phase when the amplitude is modulated, which provides us valuable information when both amplitude and phase are to be controlled. Our demonstration not only paves the road to applications such as quantum information processing that requires high extinction ratio AMs but also significantly alleviates the tight fabrication tolerance needed for large-scale integrated photonics.

4.
Hematol Oncol ; 35(4): 894-899, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26947932

RESUMEN

Ring 21 is an unstable structural abnormality of chromosome 21 that can lead to RUNX1 gene amplification. We present a unique case with a carrier patient of a constitutional ring chromosome 21 (partial monosomy and trisomy 21) with dysmorphic features and congenital malformations phenotype, who developed acute myeloid leukaemia with myelodysplasia-related changes and two ring 21 chromosomes with RUNX1 amplification. The patient's constitutional ring 21 chromosome showed alterations in tumour suppressor genes, and oncogenes, but not in RUNX1. RUNX1 gene expression at acute myeloid leukaemia diagnosis, showed no upregulation, so other genes may also be the genetic amplification targets in this patient. Copyright © 2016 John Wiley & Sons, Ltd.


Asunto(s)
Subunidad alfa 2 del Factor de Unión al Sitio Principal/genética , Leucemia Mieloide Aguda/genética , Síndromes Mielodisplásicos/genética , Preescolar , Cromosomas Humanos Par 21/genética , Femenino , Amplificación de Genes , Humanos , Cromosomas en Anillo
5.
Int J Audiol ; 54(8): 499-506, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25832123

RESUMEN

OBJECTIVE: The aim of the present study was to provide thresholds data as a function of age for an otologically normal population in Spain, compared to the current ISO 7029 (2000) standard. DESIGN: A prospective study in an otologically screened population. STUDY SAMPLE: Data was collected from 1175 otologically-normal persons aged between 5 and 90 years. Inclusion criteria involved those listed in ISO 389-1 (1998) and the 8253-1 (2010). Suitability for inclusion was evaluated through interview, based on a questionnaire, and physical examination. RESULTS: The hearing thresholds decreased slightly from 125 to 2000 Hz. From 2000 Hz onwards the thresholds increased; this increase being more pronounced with increasing frequency and age. No statistically significant sex differences were found. The hearing threshold levels in the present study were higher (poorer) than the ones provided by ISO 7029 (2000). CONCLUSIONS: Results from this study suggest that the thresholds listed in ISO 7029 (2000) may be too restrictive, and could be useful in formulating the ISO 7029 update.


Asunto(s)
Audiometría de Tonos Puros/normas , Umbral Auditivo , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Audiometría de Tonos Puros/estadística & datos numéricos , Niño , Preescolar , Femenino , Voluntarios Sanos , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Estándares de Referencia , España , Adulto Joven
6.
Adv Physiol Educ ; 39(3): 209-13, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26330040

RESUMEN

The aim of the present work was to transfer a wider concept of teamwork and self-learning to the laboratory, encouraging students' capabilities when seeking, acquiring, and processing knowledge. This educational innovation was carried out with a total of 38 students (fourth year of degree in Biology) in the area of physiology (Advances in Reproduction course) at University of Córdoba in Córdoba, Spain. The design of the project's application methodology consisted of establishing a way in which problems would be tackled in the practical classes. For this purpose, the different tasks were set up so that students could relate them to the concepts learned in the theory classes. On the first day of class, the project was presented to the students. Groups of two to three students worked in the laboratory and set up an outline of the protocol of the practical work that they had done. This outline was performed individually and sent to the lecturers through a learning management system (Moodle). The teachers gave feedback and assessed student submissions. Upon finishing the course, students completed a survey. The project-based learning method promotes practical self-learning on the part of students. This methodology demonstrated to us that it stimulates a critical and self-critical capacity in students, both individually and in groups, and that writing didactic practical material helped students to enhance their theory knowledge. The experiment was a success in view of the scores obtained upon finishing the subject.


Asunto(s)
Educación de Pregrado en Medicina/métodos , Evaluación Educacional/métodos , Laboratorios , Fisiología/educación , Aprendizaje Basado en Problemas/métodos , Animales , Femenino , Retroalimentación Formativa , Humanos , Conocimiento , Masculino , Ratones , Modelos Animales , Facultades de Medicina/organización & administración , España , Estudiantes de Medicina/estadística & datos numéricos , Adulto Joven
7.
Eur Arch Otorhinolaryngol ; 271(12): 3121-6, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24609645

RESUMEN

Although dimethyl sulfoxide (DMSO) is one of the most common solvents employed in otoprotection studies, its effect on the inner ear remains unknown. Only a few in vitro studies have addressed the effect of DMSO in cochlear cells. Up to the date, no in vivo functional studies have been reported. To determine the effect of intratympanic DMSO application in the inner ear, and to evaluate its effect in combination with cisplatin in Wistar rats, twelve Wistar rats were randomly assigned into two groups. Group A received intratympanic 1 % DMSO in both ears. Group B received intraperitoneal cisplatin (10 mg/kg) and intratympanic 0.5 % DMSO in the right ear and saline solution in the left ear. Functional changes were evaluated with Auditory Steady-State Responses before and 5 days after the procedure. Morphological changes were studied by means of confocal laser scanning microscopy following the removal of the temporal bones and cochlear dissection. Hearing threshold levels in group A did not show any statistically significant changes after the treatment. In group B, significant differences between pre- and post-treatment were found, with no statistically significant variations between right (DMSO) and left ear (saline solution). We suggest that DMSO could be safely used to dissolve hydrophobic compounds in otoprotection studies without interfering with the cochlear damage produced by cisplatin.


Asunto(s)
Cisplatino/toxicidad , Cóclea , Dimetilsulfóxido/farmacología , Animales , Antineoplásicos/farmacología , Cóclea/efectos de los fármacos , Cóclea/patología , Citoprotección , Masculino , Sustancias Protectoras/farmacología , Ratas , Ratas Wistar
8.
Int J Audiol ; 53(9): 595-603, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24793886

RESUMEN

OBJECTIVE: To determine common reference equivalent threshold sound pressure levels (RETSPL) for the earphones used in the extended high-frequency (EHF) range, as different earphones are commercially available, but there are not RETSPLs for each model. DESIGN: Hearing threshold sound pressure levels were measured up to 20 kHz for the Sennheiser HDA 200 audiometric earphone, and were compared to the ISO 389-5 (2006) norm and other investigations using that earphone and different ones. STUDY SAMPLE: A total of 223 otologically-normal subjects (aged 5-25 years old) participated in the hearing determination. RESULTS: The results are in good agreement with previous studies of hearing thresholds using the same and other earphones. CONCLUSIONS: The results of the present investigation are relevant for the international standard for the calibration of audiometric equipment in the 8 to 16 kHz frequency range, ISO 389-5. The data may be used for a future update of the RETSPL for circumaural and insert audiometric earphones.


Asunto(s)
Estimulación Acústica/instrumentación , Acústica/instrumentación , Audiometría de Tonos Puros/instrumentación , Vías Auditivas/fisiología , Umbral Auditivo , Percepción de la Altura Tonal , Adolescente , Adulto , Factores de Edad , Calibración , Niño , Preescolar , Diseño de Equipo , Femenino , Humanos , Masculino , Presión , Valores de Referencia , Sonido , Adulto Joven
9.
Int J Audiol ; 53(8): 531-45, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24749665

RESUMEN

OBJECTIVE: The aim of the present study was to study patterns in the extended spectrum of the human hearing (0.125 to 20 kHz) in order to obtain reference thresholds. Then, we compare our values with existing results at extended high-frequencies (8 to 20 kHz) in an attempt to establish new standards for potential international adoption. DESIGN: A prospective study in a group of otologically healthy subjects. STUDY SAMPLE: A total of 645 subjects aged between 5 and 90 years were recruited. Pure-tone thresholds were determined for conventional and extended high-frequencies. RESULTS: There was an increase in the hearing thresholds as a function of frequency and age. For the 20 to 69 years old group, thresholds were lower in females than in males, especially at 12.5 and 16 kHz. Our threshold values are comparable to those presented in previous studies that used different instrumentation and populations. CONCLUSIONS: When comparing different studies the hearing thresholds were found to be similar. Therefore, it would be possible to establish international standard thresholds.


Asunto(s)
Audiometría de Tonos Puros/normas , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Femenino , Voluntarios Sanos , Humanos , Masculino , Persona de Mediana Edad , Valores de Referencia , Adulto Joven
10.
Hipertens Riesgo Vasc ; 41(2): 95-103, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38508877

RESUMEN

INTRODUCTION: Evidence about nefroprotective effect with RAAS blockers in elderly patients with chronic kidney disease (CKD) without proteinuria is lacking. The primary outcome of our study is to evaluate the impact of RAAS blockers in CKD progression in elderly patients without proteinuria. MATERIALS AND METHODS: Multicenter open-label, randomized controlled clinical trial including patients over 65 year-old with hypertension and CKD stages 3-4 without proteinuria. Patients were randomized in a 1:1 ratio to either receive RAAS blockers or other antihypertensive drugs and were followed up for three years. Primary outcome is estimated glomerular filtration rate (eGFR) decline at 3 years. Secondary outcome measures include BP control, renal and cardiovascular events and mortality. RESULTS: 88 patients were included with a mean age of 77.9±6.1 years and a follow up period of 3 years: 40 were randomized to RAAS group and 48 to standard treatment. Ethiology of CKD was: 53 vascular, 16 interstitial and 19 of unknown ethiology. In the RAAS group eGFR slope during follow up was -4.3±1.1ml/min, whereas in the standard treatment group an increase on eGFR was observed after 3 years (+4.6±0.4ml/min), p=0.024. We found no differences in blood pressure control, number of antihypertensive drugs, albuminuria, potassium serum levels, incidence of cardiovascular events nor mortality during the follow up period. CONCLUSIONS: In elderly patients without diabetes nor cardiopathy and with non proteinuric CKD the use of RAAS blockers does not show a reduction in CKD progression. The PROERCAN (PROgresión de Enfermedad Renal Crónica en ANcianos) trial (trial registration: NCT03195023).


Asunto(s)
Hipertensión , Insuficiencia Renal Crónica , Humanos , Anciano , Anciano de 80 o más Años , Sistema Renina-Angiotensina , Antihipertensivos/farmacología , Antihipertensivos/uso terapéutico , Inhibidores de la Enzima Convertidora de Angiotensina/farmacología , Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Hipertensión/complicaciones , Hipertensión/tratamiento farmacológico , Insuficiencia Renal Crónica/complicaciones , Insuficiencia Renal Crónica/tratamiento farmacológico , Proteinuria/tratamiento farmacológico , Proteinuria/etiología
11.
Antimicrob Agents Chemother ; 57(2): 1053-6, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23183438

RESUMEN

Subtype-dependent selection of HIV-1 reverse transcriptase resistance mutation K65R was previously observed in cell culture and small clinical investigations. We compared K65R prevalence across subtypes A, B, C, F, G, and CRF02_AG separately in a cohort of 3,076 patients on combination therapy including tenofovir. K65R selection was significantly higher in HIV-1 subtype C. This could not be explained by clinical and demographic factors in multivariate analysis, suggesting subtype sequence-specific K65R pathways.


Asunto(s)
Adenina/análogos & derivados , Fármacos Anti-VIH/uso terapéutico , Transcriptasa Inversa del VIH/genética , Organofosfonatos/uso terapéutico , Inhibidores de la Transcriptasa Inversa/uso terapéutico , Adenina/uso terapéutico , Adulto , Farmacorresistencia Viral/genética , Quimioterapia Combinada , Femenino , Variación Genética , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/virología , VIH-1/clasificación , VIH-1/efectos de los fármacos , VIH-1/enzimología , VIH-1/genética , Humanos , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , ADN Polimerasa Dirigida por ARN/genética , Inhibidores de la Transcriptasa Inversa/farmacología , Tenofovir
12.
J Antimicrob Chemother ; 68(2): 419-23, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23027713

RESUMEN

OBJECTIVES: The use of tenofovir is highly associated with the emergence of mutation K65R, which confers broad resistance to nucleoside/nucleotide analogue reverse transcriptase inhibitors (NRTIs), especially when tenofovir is combined with other NRTIs also selecting for K65R. Although recent HIV-1 treatment guidelines discouraging these combinations resulted in reduced K65R selection with tenofovir, updated information on the impact of currently recommended regimens on the population selection rate of K65R is presently lacking. METHODS: In this study, we evaluated changes over time in the selection rate of resistance mutation K65R in a large population of 2736 HIV-1-infected patients failing combination antiretroviral treatment between 2002 and 2010. RESULTS: The K65R resistance mutation was detected in 144 patients, a prevalence of 5.3%. A large majority of observed K65R cases were explained by the use of tenofovir, reflecting its wide use in clinical practice. However, changing patterns over time in NRTIs accompanying tenofovir resulted in a persistent decreasing probability of K65R selection by tenofovir-based therapy. The currently recommended NRTI combination tenofovir/emtricitabine was associated with a low probability of K65R emergence. For any given dual NRTI combination including tenofovir, higher selection rates of K65R were consistently observed with a non-nucleoside reverse transcriptase inhibitor than with a protease inhibitor as the third agent. DISCUSSION: Our finding of a stable time trend of K65R despite elevated use of tenofovir illustrates increased potency of current HIV-1 therapy including tenofovir.


Asunto(s)
Adenina/análogos & derivados , Fármacos Anti-VIH/administración & dosificación , Farmacorresistencia Viral , Infecciones por VIH/tratamiento farmacológico , VIH-1/efectos de los fármacos , Mutación Missense , Organofosfonatos/administración & dosificación , Selección Genética , Adenina/administración & dosificación , Terapia Antirretroviral Altamente Activa/métodos , Infecciones por VIH/virología , Transcriptasa Inversa del VIH/genética , VIH-1/genética , Humanos , Tenofovir , Factores de Tiempo , Insuficiencia del Tratamiento
13.
Opt Express ; 21(5): 6169-79, 2013 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-23482185

RESUMEN

We present theoretical results of a low-loss all-optical switch based on electromagnetically induced transparency and the quantum Zeno effect in a microdisk resonator. We show that a control beam can modify the atomic absorption of the evanescent field which suppresses the cavity field buildup and alters the path of a weak signal beam. We predict more than 35 dB of switching contrast with less than 0.1 dB loss using just 2 µW of control-beam power for signal beams with less than single photon intensities inside the cavity.

14.
Nat Genet ; 26(1): 97-102, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10973258

RESUMEN

Genetic and pharmacological studies have defined a role for the melanocortin-4 receptor (Mc4r) in the regulation of energy homeostasis. The physiological function of Mc3r, a melanocortin receptor expressed at high levels in the hypothalamus, has remained unknown. We evaluated the potential role of Mc3r in energy homeostasis by studying Mc3r-deficient (Mc3r(-/-)) mice and compared the functions of Mc3r and Mc4r in mice deficient for both genes. The 4-6-month Mc3r-/- mice have increased fat mass, reduced lean mass and higher feed efficiency than wild-type littermates, despite being hypophagic and maintaining normal metabolic rates. (Feed efficiency is the ratio of weight gain to food intake.) Consistent with increased fat mass, Mc3r(-/-) mice are hyperleptinaemic and male Mc3r(-/-) mice develop mild hyperinsulinaemia. Mc3r(-/-) mice did not have significantly altered corticosterone or total thyroxine (T4) levels. Mice lacking both Mc3r and Mc4r become significantly heavier than Mc4r(-/-) mice. We conclude that Mc3r and Mc4r serve non-redundant roles in the regulation of energy homeostasis.


Asunto(s)
Tejido Adiposo/metabolismo , Peso Corporal , Receptores de Corticotropina/genética , Receptores de Corticotropina/fisiología , Factores de Edad , Animales , Southern Blotting , Temperatura Corporal , Calorimetría , Corticosterona/biosíntesis , Conducta Alimentaria , Femenino , Genotipo , Glucosa/biosíntesis , Humanos , Hiperinsulinismo/genética , Hibridación in Situ , Insulina/biosíntesis , Leptina/biosíntesis , Masculino , Ratones , Ratones Noqueados , Modelos Genéticos , Actividad Motora , Obesidad/genética , Oligopéptidos/farmacología , Fenotipo , Isoformas de Proteínas , Receptor de Melanocortina Tipo 3 , Receptor de Melanocortina Tipo 4 , Receptores de Corticotropina/química , Receptores de Péptidos/genética , Receptores de Péptidos/metabolismo , Recombinación Genética , Tiroxina/biosíntesis , Factores de Tiempo , Distribución Tisular , alfa-MSH/análogos & derivados
15.
J Evol Biol ; 25(4): 726-39, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22320146

RESUMEN

Drosophila madeirensis is an endemic species of Madeira that inhabits the island Laurisilva forest. Nucleotide variation in D. madeirensis is analysed in six genomic regions and compared to that previously reported for the same regions in Drosophila subobscura, an abundant species in the Palearctic region that is closely related to D. madeirensis. The gene regions analysed are distributed along the O(3) inversion. The O(3) arrangement is monomorphic in D. madeirensis, and it was present in ancestral populations of D. subobscura but went extinct in this species after the origin of the derived O(ST) and O(3+4) arrangements. Levels of nucleotide polymorphism in D. madeirensis are similar to those present in the O(ST) and O(3+4) arrangements of D. subobscura, and the frequency spectrum is skewed towards rare variants. Purifying selection against deleterious nonsynonymous mutations is less effective in D. madeirensis. Although D. madeirensis and D. subobscura coexist at present in Madeira, no clear evidence of introgression was detected in the studied regions.


Asunto(s)
Drosophila/clasificación , Drosophila/genética , Polimorfismo Genético , Animales , Tipificación de Secuencias Multilocus , Filogeografía , Portugal
16.
B-ENT ; 8(4): 295-7, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23409561

RESUMEN

PROBLEM: Approximately 90% of tumours of cerebellopontine angle and internal auditory canal are vestibular schwannomas (acoustic neuromas) and meningiomas. Lipochoristomas are rare benign masses that represent only 0.15% of cases. METHODOLOGY: We report the case of a 39-year-old man who consulted us for right-sided hearing loss and tinnitus. RESULTS: Tonal audiometry showed a down-sloping right sensorineural hearing loss in frequencies above 2000 Hz. Magnetic resonance imaging (MRI) revealed a heterogeneous lesion in the right internal auditory canal with areas of hyperintensity on noncontrast T1-weighted MRI and suppression of much of the signal of the lesion with persistence of some areas of enhancement on T1-weighted fat-suppressed images. CONCLUSION: Correct imaging diagnosis through MRI (high signal intensity on noncontrast T1-weighted images together with a missing signal in fat suppression sequences) is essential in order to avoid unnecessary surgery or radiation therapy, which are not recommended in the treatment of these lesions.


Asunto(s)
Coristoma/diagnóstico , Conducto Auditivo Externo , Adulto , Coristoma/terapia , Humanos , Masculino
17.
Sci Rep ; 12(1): 4470, 2022 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-35296711

RESUMEN

Vertically aligned arrays are a frequent outcome in the nanowires synthesis by self-assembly techniques or in its subsequent processing. When these nanowires are close enough, quantum electron tunneling is expected between them. Then, because extended or localized electronic states can be established in the wires by tuning its electron density, the tunneling configuration between adjacent wires could be conveniently adjusted by an external gate. In this contribution, by considering the collective nature of electrons using a Yukawa-like effective potential, we explore the electron interaction between closely spaced, parallel nanowires while varying the electron density and geometrical parameters. We find that, at a low-density Wigner crystal regime, the tunneling can take place between adjacent localized states along and transversal to the wires axis, which in turn allows to create two- and three-dimensional electronic distributions with valuable potential applications.

18.
Sci Rep ; 12(1): 20183, 2022 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-36418913

RESUMEN

The possibility of crystalline states of interacting electrons, known as Wigner crystals, has been intensively studied in each of the three dimensions. One-dimensional (1D) systems, however, can be interconnected forming two-dimensional (2D) lattices, being a three-terminal Y-junction (Y-J) the simplest one. Then, even when electrons in the individual branches of the Y are confined in 1D, as the Y-J is in 2D, one could expect significant differences in the crystalline state of the electron gas in a Y-J. With the recent report of fabrication of defect-free GaAs/AlGaAs Y-Js by epitaxial methods, the study of semiconductor Y-Js acquires a special relevance due to its eventual direct exploration. Here, by considering the collective electron interactions using a Yukawa-like effective potential, we explore a two-electron distribution in nanowire Y-Js by modulating its electron density via a screening parameter. We find that the electrons changes from a quasi-continuous to a Wigner molecule-like distribution when the electron density decreases in the Y-J. In bold contrast to the strict 1D case, where equidistant distributions of equal density are obtained in the Wigner regime, in the Y-J equidistant distributions of asymmetric density are induced. We also explore the effect of an external electric field acting along the Y-axis on the asymmetric distributions.

19.
J Cancer Policy ; 34: 100370, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36375808

RESUMEN

BACKGROUND: The invasion of Ukraine by Russia in February 2022 has resulted in destruction of healthcare infrastructure and triggered the largest wave of internally displaced populations and refugees since World War Two. Conflicts in transitioned countries such as Ukraine create new non-communicable disease (NCD) challenges, especially for cancer care for refugees and humanitarian assistance in host countries. In the early days, rapid attempts were made to model possible impacts. METHODS: By evaluating open source intelligence used in the first three months of the conflict through snowball search methods, we aimed to address: (i) burden of cancer in Ukrainian population, specifically considering translating to the refugees population, and its cancer care capacity; ii) baseline capacity/strengths of cancer systems in initial host countries. Moreover, using a baseline scenario based on crude cancer incidence in Ukraine, and considering data from UNHCR, we estimated how cancer cases would be distributed across host countries. Finally, a surveillance assessment instrument was created, intersecting health system's capacity and influx of internally displaced populations and refugees. FINDINGS AND CONCLUSIONS: The total new cancer patients per month in pre-conflict Ukraine was estimated as 13,106, of which < 1 % are paediatric cases. The estimated cancer cases in the refugee population (combining prevalent and incident), assuming 7.5 million refugees by July 2022 and a female:male ratio of 9:1, was 33,121 individuals (Poland: 19284; Hungary: 3484; Moldova: 2651; Slovakia: 2421; Romania: 5281). According to our assessments, Poland is the only neighbouring country classified as green/yellow for cancer capacity, i.e. sufficient ablility to absorb additional burden into national health system; Slovakia we graded as yellow, Hungary and Romania as yellow/red and Moldova as red.


Asunto(s)
Neoplasias , Enfermedades no Transmisibles , Refugiados , Sistemas de Socorro , Humanos , Masculino , Femenino , Niño , Naciones Unidas , Atención a la Salud , Neoplasias/epidemiología
20.
J Evol Biol ; 24(6): 1263-73, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21443648

RESUMEN

The X chromosome is known to exert a disproportionately large effect on characters related to post-zygotic reproductive isolation. There is also growing evidence about the important role of the chromosomal regions with reduced recombination (such as inversions) in maintaining the identity of closely related species. Using molecular markers, we examine the effect of different regions of the X chromosome on determination of hybrid traits (viability, testes size, sperm motility and morphological anomalies) in hybrid males between Drosophila madeirensis and Drosophila subobscura. The preponderant effect of a region localized inside the A2 inversion in the X chromosome in all hybrid traits is identified. Other marked regions exert a weaker influence or only influence some of the hybrid trait. Our results confirm the crucial role of sex-linked chromosomal inversion in preserving the identity of species with incomplete reproductive isolation. The specific genomic make-up of parental lines used to perform crosses has a great effect on hybrid fitness.


Asunto(s)
Cromosomas de Insectos , Drosophila/fisiología , Conducta Sexual Animal , Aislamiento Social , Animales , Femenino , Fertilidad/genética , Flujo Génico , Marcadores Genéticos , Hibridación Genética , Masculino , Especificidad de la Especie , Cromosoma X
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA