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4.
Anaesthesia ; 77(3): 326-338, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34855986

RESUMEN

Videolaryngoscopes are thought to improve glottic view and facilitate tracheal intubation compared with the Macintosh direct laryngoscope. However, we currently do not know which one would be the best choice in most patients undergoing anaesthesia. We designed this systematic review with network meta-analyses to rank the different videolaryngoscopes and the Macintosh direct laryngoscope. We conducted searches in PubMed and a further five databases on 11 January 2021. We included randomised clinical trials with patients aged ≥16 years, comparing different videolaryngoscopes, or videolaryngoscopes with the Macintosh direct laryngoscope for the outcomes: failed intubation; failed first intubation attempt; failed intubation within two attempts; difficult intubation; percentage of glottic opening seen; difficult laryngoscopy; and time needed for intubation. We assessed the quality of evidence according to GRADE recommendations and included 179 studies in the meta-analyses. The C-MAC and C-MAC D-Blade were top ranked for avoiding failed intubation, but we did not find statistically significant differences between any two distinct videolaryngoscopes for this outcome. Further, the C-MAC D-Blade performed significantly better than the C-MAC Macintosh blade for difficult laryngoscopy. We found statistically significant differences between the laryngoscopes for time to intubation, but these differences were not considered clinically relevant. The evidence was judged as of low or very low quality overall. In conclusion, different videolaryngoscopes have differential intubation performance and some may be currently preferred among the available devices. Furthermore, videolaryngoscopes and the Macintosh direct laryngoscope may be considered clinically equivalent for the time taken for tracheal intubation. However, despite the rankings from our analyses, the current available evidence is not sufficient to ensure significant superiority of one device or a small set of them over the others for our intubation-related outcomes.


Asunto(s)
Intubación Intratraqueal/métodos , Laringoscopía/métodos , Ensayos Clínicos Controlados Aleatorios como Asunto/métodos , Procedimientos y Técnicas Asistidas por Video , Adulto , Humanos , Intubación Intratraqueal/normas , Laringoscopía/normas , Metaanálisis en Red , Ensayos Clínicos Controlados Aleatorios como Asunto/normas
5.
Annu Int Conf IEEE Eng Med Biol Soc ; 2021: 3427-3430, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34891976

RESUMEN

Computer-aided detection algorithms applied to CT lung imaging have the potential to objectively quantify pulmonary pathology. We aim to develop an automatic classification method based on textural features able to classify healthy and pathological patterns on CT lung images and to quantify the extent of each disease pattern in a group of patients with chronic hypersensitivity pneumonitis (cHP), in comparison to pulmonary function tests (PFTs).27 cHP patients were scanned via high resolution CT (HRCT) at full-inspiration. Regions of interest (ROIs) were extracted and labeled as normal (NOR), ground glass opacity (GGO), reticulation (RET), consolidation (C), honeycombing (HB) and air trapping (AT). For each ROI, statistical, morphological and fractal parameters were computed. For automatic classification, we compared two classification methods (Bayesian and Support Vector Machine) and three ROI sizes. The classifier was therefore applied to the overall CT images and the extent of each class was calculated and compared to PFTs. Better classification accuracy was found for the Bayesian classifier and the 16x16 ROI size: 92.1±2.7%. The extent of GGO, HB and NOR significantly correlated with forced vital capacity (FVC) and the extent of NOR with carbon monoxide diffusing capacity (DLCO).Clinical Relevance- Texture analysis can differentiate and objectively quantify pathological classes in the lung parenchyma and may represent a quantitative diagnostic tool in cHP.


Asunto(s)
Alveolitis Alérgica Extrínseca , Enfermedades Pulmonares , Alveolitis Alérgica Extrínseca/diagnóstico por imagen , Teorema de Bayes , Humanos , Pruebas de Función Respiratoria , Tomografía Computarizada por Rayos X
6.
Anaesthesia ; 74(9): 1147-1152, Ago., 28, 2019. ilus, tab
Artículo en Inglés | Sec. Est. Saúde SP, SESSP-IDPCPROD, Sec. Est. Saúde SP | ID: biblio-1015569

RESUMEN

We examined the potential for voice sounds to predict a difficult airway as compared with prediction by the modified Mallampati test. A total of 453 patients scheduled for elective surgery under general anaesthesia with tracheal intubation were studied. Five phonemes were recorded and their formants analysed. Difficult laryngoscopy was defined as the Cormack-Lehane grade 3 or 4. Univariate and multivariate logistic regression were used to examine the association between some variables (mouth opening, sternomental distance, modified Mallampati and formants) and difficult laryngoscopy. Difficult laryngoscopy was reported in 29/453 (6.4%) patients. Among five regression models evaluated, the model achieving better performance to predict difficult laryngoscopy, after a variable selection criteria (stepwise, multivariate) and included a modified Mallampati classification (OR 2.920; 95%CI 1.992-4.279; p < 0.001), first formant of /i/(iF1) (OR 1.003; 95%CI 1.002-1.04; p < 0.001), and second formant of /i/(iF2) (OR 0.998; 95%CI 0.997-0.998; p < 0.001). The receiver operating curve for a regression model that included both formants and Mallampati showed an area under curve of 0.918, higher than formants alone (area under curve 0.761) and modified Mallampati alone (area under curve 0.874). Voice presented a significant association with difficult laryngoscopy during general anaesthesia showing a 76.1% probability of correctly classifying a randomly selected patient. (AU)


Asunto(s)
Humanos , Femenino , Adulto , Persona de Mediana Edad , Voz/fisiología , Cuidados Preoperatorios , Intubación Intratraqueal , Anestesia , Laringoscopía/métodos
7.
Anaesthesia ; 74(9): 1147-1152, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31183861

RESUMEN

We examined the potential for voice sounds to predict a difficult airway as compared with prediction by the modified Mallampati test. A total of 453 patients scheduled for elective surgery under general anaesthesia with tracheal intubation were studied. Five phonemes were recorded and their formants analysed. Difficult laryngoscopy was defined as the Cormack-Lehane grade 3 or 4. Univariate and multivariate logistic regression were used to examine the association between some variables (mouth opening, sternomental distance, modified Mallampati and formants) and difficult laryngoscopy. Difficult laryngoscopy was reported in 29/453 (6.4%) patients. Among five regression models evaluated, the model achieving better performance to predict difficult laryngoscopy, after a variable selection criteria (stepwise, multivariate) and included a modified Mallampati classification (OR 2.920; 95%CI 1.992-4.279; p < 0.001), first formant of /i/(iF1) (OR 1.003; 95%CI 1.002-1.04; p < 0.001), and second formant of /i/(iF2) (OR 0.998; 95%CI 0.997-0.998; p < 0.001). The receiver operating curve for a regression model that included both formants and Mallampati showed an area under curve of 0.918, higher than formants alone (area under curve 0.761) and modified Mallampati alone (area under curve 0.874). Voice presented a significant association with difficult laryngoscopy during general anaesthesia showing a 76.1% probability of correctly classifying a randomly selected patient.


Asunto(s)
Intubación Intratraqueal/métodos , Laringoscopía/métodos , Cuidados Preoperatorios/métodos , Voz/fisiología , Adulto , Anestesia General , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Prospectivos
8.
Theriogenology ; 119: 1-9, 2018 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-29958134

RESUMEN

The aim of this work was to evaluate the proteomic changes that occurred in the frozen-thawed bovine spermatozoa after the addition of l-arginine (L-arg) during in vitro sperm capacitation. Aspects related to the sperm capacitation pattern like membrane integrity, mitochondrial activity, sperm motility and vigor, and the sperm proteome were determined. These were respectively assessed by chlortetracycline staining, H342/PI, JC-1, light microscopy, and the proteomic abundance by nUPLC-MS/MS analysis. Frozen-thawed sperm from three Nellore bulls were capacitated in vitro for 3 h in sp-TALP medium supplemented with 20 µg/mL heparin (Control) or with 20 µg/mL heparin plus 1 mM L-arg (L-arg group). Data were subjected to analysis of variance and means compared by SNK test at 5% probability. When compared to Control, the percentage of sperm motility was higher in the L-arg group (P < 0.05). For test data after 3 h of incubation, sperm capacitated with L-arg showed higher membrane integrity and mitochondrial potential when compared to Control (P < 0.05). Moreover, we observed an increase in the percentage of capacitated sperm pattern (P < 0.05). Protein abundance analysis identified 367 proteins. Forty proteins were differentially abundant between Control and L-arg group (P < 0.05), of which 11 were up-regulated, and 29 were down-regulated in L-arg group. In addition, we observed that one protein was uniquely abundant in the L-arg group. Our findings indicate that the addition of L-arg to the culture medium presented a differential protein abundance pattern and increased the bovine frozen-thawed sperm quality and the percentage of capacitated sperm. The proteomic changes observed may be linked to the molecular mechanisms involved in the action of L-arg on the in vitro sperm capacitation of cattle.


Asunto(s)
Arginina/farmacología , Bovinos , Regulación de la Expresión Génica/efectos de los fármacos , Proteoma/efectos de los fármacos , Espermatozoides/efectos de los fármacos , Animales , Criopreservación/veterinaria , Congelación , Masculino , Análisis de Semen/veterinaria , Preservación de Semen/veterinaria , Capacitación Espermática , Espermatozoides/metabolismo
9.
Braz J Med Biol Res ; 51(3): e6329, 2018 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-29513879

RESUMEN

Recent evidence shows that chronic ethanol consumption increases endothelin (ET)-1 induced sustained contraction of trabecular smooth muscle cells of the corpora cavernosa in corpus cavernosum of rats by a mechanism that involves increased expression of ETA and ETB receptors. Our goal was to evaluate the effects of alcohol and diabetes and their relationship to miRNA-155, miRNA-199 and endothelin receptors in the corpus cavernosum and blood of rats submitted to the experimental model of diabetes mellitus and chronic alcoholism. Forty-eight male Wistar rats were divided into four groups: control (C), alcoholic (A), diabetic (D), and alcoholic-diabetic (AD). Samples of the corpus cavernosum were prepared to study the protein expression of endothelin receptors by immunohistochemistry and expression of miRNAs-155 and -199 in serum and the cavernous tissue. Immunostaining for endothelin receptors was markedly higher in the A, D, and AD groups than in the C group. Moreover, a significant hypoexpression of the miRNA-199 in the corpus cavernosum tissue from the AD group was observed, compared to the C group. When analyzing the microRNA profile in blood, a significant hypoexpression of miRNA-155 in the AD group was observed compared to the C group. The miRNA-199 analysis demonstrated significant hypoexpression in D and AD groups compared to the C group. Our findings in corpus cavernosum showed downregulated miRNA-155 and miRNA-199 levels associated with upregulated protein expression and unaltered mRNA expression of ET receptors suggesting decreased ET receptor turnover, which can contribute to erectile dysfunction in diabetic rats exposed to high alcohol levels.


Asunto(s)
Alcoholismo/metabolismo , Diabetes Mellitus Experimental/metabolismo , Endotelina-1/análisis , MicroARNs/análisis , Pene/metabolismo , Receptor de Endotelina A/análisis , Receptor de Endotelina B/análisis , Alcoholismo/complicaciones , Alcoholismo/fisiopatología , Animales , Diabetes Mellitus Experimental/complicaciones , Diabetes Mellitus Experimental/fisiopatología , Inmunohistoquímica , Masculino , Pene/fisiopatología , Ratas , Ratas Wistar
10.
Transplant Proc ; 49(10): 2247-2250, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29198654

RESUMEN

The Maryland aggregate pathology index (MAPI) score is an important tool developed to help pathologists in evaluating potential organs for transplantation. It is based on analysis of five variables (present or absent): arteriolar hyalinosis (4 points), periglomerular fibrosis (2 points), arterial wall-lumen ratio superior to 0.5 (2 points), global glomerulosclerosis in more than 15% of glomeruli (2 points), and interstitial scar (3 points). Kidneys with a MAPI score >7 points are considered inadequate for donation. This study aimed to evaluate pathology agreement between frozen sections (FS) and paraffin sections (PS) using the MAPI score in a cohort of 262 biopsy specimens obtained at the General Hospital of Fortaleza, Brazil. We performed a retrospective review of pathological reports of FS (signed out by an on-call pathologist) and their corresponding PS (authorized by a specialist in renal pathology). Agreement was calculated using the Kappa test. Kappa values ranging from 0.29 to 0.51 were obtained when MAPI parameters were separately evaluated. When the score was used, the coefficient was 0.59. Fourteen of 262 kidneys were classified as inadequate for donation using PS and 8 cases were diagnosed using FS. There were no differences between wedge-shaped and filiform samples, apart from the mean number of glomeruli. Discordant cases had no statistical difference from concordant ones when clinical and macroscopic pathological parameters were analyzed. The MAPI score can be useful to minimize disagreements between FS and PS, but more effort should be made to standardize criteria and enable pathologists to recognize chronic lesions in FS samples.


Asunto(s)
Selección de Donante/métodos , Secciones por Congelación , Riñón/patología , Adhesión en Parafina , Trasplantes/patología , Adolescente , Adulto , Biopsia , Brasil , Femenino , Humanos , Trasplante de Riñón , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Adulto Joven
11.
Eur J Gynaecol Oncol ; 38(3): 368-371, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29693875

RESUMEN

OBJECTIVES: To compare the use of topical 5% imiquimodt (IMQ) cream or CO2 laser vaponization as the treatment of vulvar inmraepithelial lesions (VIN) 2/3 and to evaluate the degrees of residual or recurrent lesions. MATERIALS AND METHODS: Twenty-nine women with VIN 2/3 were separated into two groups, according to the proposed treatments. All were submitted to collection of vulvar swabs for DNA genotyping of human papillomavirus (HPV), vulvoscopy, and biopsy of the found lesions. After treatment they were followed up in quarterly consultations to (until) possible appearance of new lesions or along one year. RESULTS: The findings were similar in effectiveness and presence of residual or recurrent lesions on the performed treatments. However, patients treated with topical 5% IMQ cream had less severe lesions in histological recurrence when compared to those submitted to the CO2 laser vaporization. CONCLUSIONS: The effectiveness of topical 5% IMQ cream was similar to that of CO2 laser vaporization. There was no difference between the treatments for the presence of residual or recurrent lesions. However, patients who received IMQ had less aggressive lesions than those submitted to the treatment with CO2 laser vaporization.


Asunto(s)
Aminoquinolinas/uso terapéutico , Antineoplásicos/uso terapéutico , Carcinoma in Situ/terapia , Láseres de Gas/uso terapéutico , Neoplasias de la Vulva/terapia , Carcinoma in Situ/patología , Femenino , Humanos , Imiquimod , Pomadas , Neoplasias de la Vulva/patología
12.
Eur J Clin Nutr ; 71(4): 434-440, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-27677370

RESUMEN

We conducted a mini-review of the literature, focusing on aging-related systemic inflammation and its association with vitamin D (VitD). As main findings, data indicate that inflammation in aging seems to have multiple origins, including immunosenescence, and from intestinal and adipose tissue, where VitD may modulate these three factors, through mechanisms not totally known. From the selected studies, three randomized clinical trials of VitD supplementation showed improvements in inflammatory status, whereas two studies did not. Ten epidemiological studies showed associations between VitD and inflammation, whereas two studies did not. One case study reinforced this association. As such, we can assume a reasonable association between VitD and inflammation in the elderly, and a promising role of supplementation in some situations. However, most studies did not take into account environmental and individual factors such as the season of the year, latitude, skin color or even the use of some medicines; in addition, the doses, time of intervention and the sample sizes differed between the studies. In conclusion, although more controlled VitD studies, both clinical and epidemiological, are necessary, it is important to remember the network of factors involved in systemic inflammation in the elderly; an understanding of the dietetic and non-dietetic factors is needed to offer a realistic approach.


Asunto(s)
Envejecimiento/sangre , Inflamación/sangre , Deficiencia de Vitamina D/sangre , Vitamina D/sangre , Anciano , Anciano de 80 o más Años , Suplementos Dietéticos , Humanos , Vitamina D/administración & dosificación , Vitaminas/administración & dosificación
13.
Int J Oral Maxillofac Surg ; 46(1): 16-23, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27745792

RESUMEN

The purpose of this study was to evaluate the immunoexpression of vascular endothelial growth factor C (VEGF-C) and VEGF receptor 3 (VEGFR-3) and their correlation with intratumoural lymphatic density (ILD) and peritumoural lymphatic density (PLD) in metastatic and non-metastatic lower lip squamous cell carcinoma (LLSCC). Twenty-five LLSCC with regional nodal metastasis and 25 LLSCC without metastasis were selected. The percentages of VEGF-C and VEGFR-3 staining in each tumour core and at the deep invasive front were assessed. PLD and ILD were determined using anti-podoplanin antibody. Immunohistochemical findings were correlated with nodal metastasis, clinical staging, local recurrence, clinical outcome, and histological grade. Cytoplasmic immunoexpression of VEGFR-3 in the tumour core was associated with metastasis (P=0.009), patient death (P=0.008), and histological grade (P<0.005). PLD, ILD, and VEGF-C expression showed no significant associations with clinicopathological parameters (P>0.05). PLD and ILD were not significantly correlated with the immunoexpression of VEGF-C or VEGFR-3 (P>0.05). There was a significant positive correlation between PLD and ILD (P=0.004), and between cytoplasmic immunoreactivity of VEGF-C and VEGFR-3 (P=0.011). These results suggest an important role for VEGFR-3 in the progression of LLSCC, and highlight the possible influence of its expression on the prognosis of these tumours. ILD and PLD may not be associated with lymph node metastasis in LLSCC.


Asunto(s)
Carcinoma de Células Escamosas/inmunología , Carcinoma de Células Escamosas/patología , Neoplasias de los Labios/inmunología , Neoplasias de los Labios/patología , Metástasis Linfática/inmunología , Metástasis Linfática/patología , Factor C de Crecimiento Endotelial Vascular/inmunología , Receptor 3 de Factores de Crecimiento Endotelial Vascular/inmunología , Femenino , Humanos , Técnicas para Inmunoenzimas , Masculino , Glicoproteínas de Membrana/inmunología , Recurrencia Local de Neoplasia , Estadificación de Neoplasias
14.
Int J Cosmet Sci ; 39(3): 241-247, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27731897

RESUMEN

Skin aging is a complex process that may be caused by factors that are intrinsic and extrinsic to the body. Ultraviolet (UV) radiation represents one of the main sources of skin damage over the years and characterizes a process known as photoaging. Among the changes that affect cutaneous tissue with age, the loss of elastic properties caused by changes in elastin production, increased degradation and/or processing produces a substantial impact on tissue esthetics and health. The occurrence of solar elastosis is one of the main markers of cutaneous photoaging and is characterized by disorganized and non-functional deposition of elastic fibers. The occurrence of UV radiation-induced alternative splicing of the elastin gene, which leads to inadequate synthesis of the proteins required for the correct assembly of elastic fibers, is a potential explanation for this phenomenon. Innovative studies have been fundamental for the elucidation of rarely explored photoaging mechanisms and have enabled the identification of effective therapeutic alternatives such as cosmetic products. This review addresses cutaneous photoaging and the changes that affect elastin in this process.


Asunto(s)
Elastina/metabolismo , Envejecimiento de la Piel , Rayos Ultravioleta , Empalme Alternativo , Cosméticos , Elastina/química , Humanos , Piel/metabolismo
15.
Theriogenology ; 88: 134-144, 2017 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-27743687

RESUMEN

Nitric oxide (NO) is identified as a signaling molecule involved in many cellular or physiological functions, including meiotic maturation of cattle oocytes. This study aimed to evaluate the effect of supplementation of culture medium with the L-arginine (L-arg, NO synthesis precursor) in nuclear maturation of oocytes, concentrations of nitrate/nitrite, progesterone (P4), and 17ß-estradiol (E2) in the culture medium; and the cyclic guanosine monophosphate (cGMP) and cyclic adenosine monophosphate (cAMP) intracellular concentrations in the cumulus-oocyte complexes (COCs) during the first hours of maturation in the presence of hemisections (HSs) of the follicular wall (control -ve). The addition of 5.0-mM L-arg increased (P < 0.05) the percentage of oocytes at the germinal vesicle breakdown stage after 7 hours of cultivation compared with control -ve. All concentrations of L-arg (2.5, 5.0, and 10.0 mM) increased the percentage of oocytes that reached the metaphase I (MI) at 15 hours (P < 0.05) but do not affect the progression from MI to metaphase II (P > 0.05) at 22 hours. All concentrations of L-arg tested increased (P < 0.05) the percentage of cumulus cells with plasma membrane integrity at 22 hours of cultivation. L-arginine did not change (P > 0.05) the nitrate/nitrite, P4, and E2 concentrations in relation to control -ve at any of the times tested. In immature COCs, immediately after being removed from the follicles (0 hours), the intracellular concentration of cGMP in the control -ve and treatment with 5-mM L-arg progressively decreased (P < 0.05) after the first hour of cultivation; however, COCs treated with 5.0-mM L-arg had higher concentrations of cGMP at 1 hour of cultivation (P < 0.05). The cAMP concentration of COCs supplemented or not with 5.0-mM L-arg progressively increased until 3 hours of cultivation and at, 6 hours, decreased (P < 0.05). The results show, in using this system, that (1) the mechanisms that give the oocyte the ability to restart the meiosis until MI after adding 5.0-mM L-arg do not involve changes in the concentration of nitrate/nitrite, P4, and E2 in the culture medium and (2) L-arg acts on a pathway that involves changing the cGMP concentration but does not involve changing cAMP concentration. More studies are needed to assess whether the observed effects of L-arg during IVM using this system are via NO or not and what the role is in increasing the viability of cumulus cells in the resumption and progression of meiosis until MI.


Asunto(s)
Arginina/farmacología , Bovinos , Células del Cúmulo/efectos de los fármacos , Técnicas de Maduración In Vitro de los Oocitos/veterinaria , Oocitos/efectos de los fármacos , Animales , Células del Cúmulo/fisiología , AMP Cíclico/genética , AMP Cíclico/metabolismo , GMP Cíclico/genética , GMP Cíclico/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Técnicas de Maduración In Vitro de los Oocitos/métodos , Oocitos/fisiología
17.
Int. j. morphol ; 32(2): 614-617, jun. 2014. ilus
Artículo en Inglés | LILACS | ID: lil-714318

RESUMEN

The rat is probably the most commonly used animal in scientific research. There are many benefits to its use such as: ability to work a large number of animals allowing greater statistical validity, the relatively short life cycles. However, the scant literature regarding the anatomy and morphology of these animals is also old and not very descriptive. The objective of this research is to study the macroscopic morphometric aspects of several parameters that have not been described yet regarding the heart of Wistar rats in different phases of their lives. Thirty-six adult male and female rats (Rattus norvegicus) weighting 150-770 g were randomly divided into 6 experimental groups. The heart was then carefully dissected and removed from the chest. After this process, the heart had their weight measured on a precision scale HELMAC HM100, and for each front section of the heart related measures were taken through a semi-automatic image analysis of Kontron Build Analyse (Minimop). The percentage ratio between the relative heart weight to body weight was between 0.5 and 0.7% in the animals with body weight up to 650 g. The maximum and minimum diameters were always statistically lower in females compared to males. The measurements showed the hearts of the females shorter, narrower, smaller and lighter than those of males. Over the life of these females, although the heart weight increases, the heart apparently keeps its shape and size. Furthermore, the hearts of males narrow and stretch along their development.


La rata es probablemente el animal más utilizado en investigaciones científicas. Hay muchos beneficios por su uso como la capacidad de trabajar con un gran número de animales permitiendo una mayor validez del punto de vista estadístico o el ciclo de vida relativamente corto del animal. Sin embargo, la escasa literatura sobre la anatomía y la morfología de la rata es antigua y no muy descriptiva. El objetivo de esta investigación fue estudiar parámetros morfométricos macroscópico no descritos con respecto al corazón de la rata Wistar en diferentes fases de la vida. Treinta y seis ratas (Rattus norvegicus) adultas, hembras y machos pesando entre 150­770 g, fueron divididas al azar en 6 grupos diferentes. El corazón fue cuidadosamente disecado y retirado del tórax. Cada corazón fue pesado en una balanza de precisión y para cada sección frontal del corazón fueron tomadas medidas relativas mediante un análisis de imágen semi-automático Kontron Build Analyse (Minimop). El porcentaje de proporción entre el peso relativo del corazón y el peso del cuerpo fue entre 0,5­0,7% en animales con peso corporal de hasta 650 g. Los diámetros máximos y mínimos fueron estadísticamente menores en hembras comparádolos con machos. Las medidas mostraron que los corazones en las hembras son más cortos, angostos, pequeños y livianos que en machos. Durante la vida de estas hembras, aunque el peso del corazón aumenta, aparentemente mantiene su forma y su tamaño. Por otro lado, los corazones de los machos se estiran y se estrechan durante su desarrollo.


Asunto(s)
Animales , Masculino , Femenino , Ratas , Corazón/anatomía & histología , Tamaño de los Órganos , Peso Corporal , Caracteres Sexuales , Ratas Wistar , Corazón/crecimiento & desarrollo
18.
Artículo en Inglés | MEDLINE | ID: mdl-24730960

RESUMEN

The metric signature topological transitions associated with the propagation of electromagnetic waves in a dispersive metamaterial with frequency-dependent and anisotropic dielectric and magnetic responses are examined in the present work. The components of the reciprocal-space metric tensor depend upon both the electric permittivity and magnetic permeability of the metamaterial, which are taken as Drude-like dispersive models. A thorough study of the frequency dependence of the metric tensor is presented which leads to the possibility of topological transitions of the isofrequency surface determining the wave dynamics inside the medium, to a diverging photonic density of states at some range of frequencies, and to the existence of large wave vectors' modes propagating through the metamaterial.

19.
Aust Dent J ; 59(1): 106-13, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24494693

RESUMEN

BACKGROUND: The highest prevalence of protein-energy undernutrition is observed during early childhood, being also a time in which the presence of dental caries can be unusually aggressive. The present study aimed to verify if different levels of undernutrition could influence the risk of early childhood caries (ECC), in the presence of other predisposing factors. METHODS: One hundred and twenty undernourished 12-70 month old children, with or without ECC, were selected. Undernourished children were classified as being mildly, moderately or severely undernourished. All children were examined for determination of decayed, missing and filled surfaces (dmfs). Total protein concentration in saliva was analysed by the Bradford method. For microbiological analysis, mitis salivarius-bacitracin agar medium was used. A binary logistic regression model was applied to test the simultaneous influence of different variables over caries experience. RESULTS: The risk of ECC was significantly higher with an increase in age (p = 0.000) and mutans streptococci counts (p = 0.032). Comparisons with the normal-weight group showed that mildly (p = 0.004) and severely undernourished children (p = 0.037) had a higher risk of experiencing ECC, but this risk was not significantly elevated among moderately undernourished children (p = 0.158). CONCLUSIONS: Our results suggest that mildly and severely undernourished children have an increased risk of experiencing dental caries. Age is highly associated with the disease in this population.


Asunto(s)
Índice CPO , Caries Dental/etiología , Desnutrición Proteico-Calórica/complicaciones , Streptococcus mutans , Preescolar , Recuento de Colonia Microbiana , Caries Dental/epidemiología , Caries Dental/microbiología , Femenino , Humanos , Lactante , Modelos Logísticos , Masculino , Prevalencia , Proteínas/análisis , Saliva/química , Saliva/microbiología
20.
Phys Rev Lett ; 111(18): 183203, 2013 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-24237516

RESUMEN

We report the direct detection of two metastable H(2^{2}S) atoms coming from the dissociation of a single cold H(2) molecule, in coincidence measurements. The molecular dissociation was induced by electron impact in order to avoid limitations by the selection rules governing radiative transitions. Two detectors, placed close to the collision center, measure the neutral metastable H(2(2)S) through a localized quenching process, which mixes the H(2^{2}S) state with the H(2^{2}P), leading to a Lyman-α detection. Our data show the accomplishment of a coincidence measurement which proves for the first time the existence of the H(2(2)S)-H(2(2)S) dissociation channel.

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