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1.
Pituitary ; 26(4): 383-392, 2023 Aug.
Article de Anglais | MEDLINE | ID: mdl-37115292

RÉSUMÉ

PURPOSE: The ellipsoid equation came in an attempt to facilitate the estimation of tumor volume, by measuring the height, width, and anteroposterior length of the lesion. The estimated tumor volume can sometimes be different between methods, thus, it is of extreme interest to evaluate if the methods are significantly different, as well as to discuss the main limitations of each one. METHODS: This is an observational, analytical, cross-sectional study. A systematic review of the literature was also performed in order to discuss the results observed in the present study. RESULTS: A total of 82 patients (43 males and 39 females) ranging in age from 15 to 78 years (mean 47.95 ± 14.76) were included in the study. Seven patients were classified as Knosp grade 0 (8.5%), 36 Knosp grade 1 (44%), 14 Knosp grade 2 (17%), 20 Knosp grade 3 (24.4%), 5 Knosp grade 4 (6.1%). The tumor volume estimated by 3D planimetric assessment, non-simplified ellipsoid equation, and simplified ellipsoid formula averaged 10.68 cm³, 10.36 cm³, and 9.9 cm³ respectively. CONCLUSION: A simplified form of the ellipsoid equation increases the divergence between the measurement obtained in planimetry, and should be discouraged, in view of the new automated methods of performing quick calculations using periodic digits. The non-simplified form underestimated the tumor volume by 2.9% on average but did so regularly. In clinical practice, measurement should be accompanied by an evaluation of tumor morphology.


Sujet(s)
Tumeurs de l'hypophyse , Mâle , Femelle , Humains , Adolescent , Jeune adulte , Adulte , Adulte d'âge moyen , Sujet âgé , Tumeurs de l'hypophyse/anatomopathologie , Charge tumorale , Études transversales , Taille d'organe , Études observationnelles comme sujet
2.
Insects ; 13(11)2022 Nov 18.
Article de Anglais | MEDLINE | ID: mdl-36421972

RÉSUMÉ

A growing number of cases of the spread and establishment of non-native species outside their previously known ranges has been reported in recent years. Here we report new distributional records of Lepturges (Lepturges) limpidus Bates, 1872 (Cerambycidae) from Argentina and investigate whether these records could represent established populations. We constructed ellipsoid envelope models to characterize climatic niches of L. limpidus, identified areas of climatic suitability, investigated the status of new records as climatic outliers, and evaluated its dependency on its known hostplant as a limiting factor for the beetle distribution. Results indicate widespread climatic suitability in the Neotropical Region, and new records are not outliers with regard to the climatic profile of L. limpidus. Association with its known hostplant is non-dependent, indicating that the species might utilize different hosts plants. New records likely represent established populations, but targeted surveys should be carried out to detect new arrivals and enable the installation of mitigation and control measures.

3.
Int. j. med. surg. sci. (Print) ; 8(3): 1-14, sept. 2021. tab, ilus, graf
Article de Anglais | LILACS | ID: biblio-1292471

RÉSUMÉ

The accuracy of internal organ volume estimation done with ultrasound (US) was found to be multifactorial. Hence, we aimed to describe and validate the volume assessment of ultrasound and standard volume estimation formulae for different shaped intra-abdominal organs using spleens and kidneys.Dissected cadaveric kidneys (n=25) and spleens (n=29) were scanned to obtain linear measurements and ultrasound auto-generated volumes (USV). Linear measurements were used to calculate the volumes manually with ellipsoid, prolate, and Lambert volume estimating formulae. The actual volumes (AV) of organs were obtained by the water displacement method. Volume assessment accuracy of USV and different formulae were compared by comparing bias, precision and Bland-Altman plot analysis. The US linear and volume measurement procedure was reliable with high inter and intra-observer agreements (linear: Chronbach's α=0.983 to 0.934; volumes: Chronbach's α=0.989). USV estimates were accurate with a high correlation to AV and low estimation bias (-5.9%). Also, prolate (bias=-0.75%) and ellipsoid formulae (bias=-3.75%) were reliable with a negligible bias in estimated volumes. Contrary, the Lambert formula was unreliable due to a high bias (41.6%). For all evaluated methods, the estimation error found to be related to the organ size (T=3.483; p=0.001), mainly when the assessed organ is larger than 50 ml. Also, the shape related estimation error found to be related to the volume estimation formula used.This study has validated the USV for kidney and splenic volume assessments while describing volume-calculating formula employed, organ size and shape as significant contributors for volume estimation accuracy.


Se encontró que la precisión de la estimación del volumen de órganos internos realizada con ultrasonido (US) es multifactorial. El objetivo fue describir y validar la evaluación de volumen mediante ecografía y las fórmulas estándar de estimación de volumen para órganos intraabdominales de diferentes formas utilizando bazos y riñones.Se evaluaron riñones cadavéricos disecados (n = 25) y bazos (n = 29) para obtener medidas lineales y volúmenes autogenerados por ultrasonido (USV). Se utilizaron medidas lineales para calcular los volúmenes manualmente con fórmulas de estimación de volumen elipsoide, prolate y Lambert. Los volúmenes reales (AV) de los órganos se obtuvieron mediante el método de desplazamiento de agua. Se comparó la precisión de la evaluación del volumen de USV y diferentes fórmulas comparando el sesgo, la precisión y el análisis de la gráfica de Bland-Altman. El procedimiento de medición lineal y de volumen mediante US fue confiable con alta concordancia inter e intraobservadores (lineal: α de Chronbach = 0,983 a 0,934; volúmenes: α de Chronbach = 0,989). Las estimaciones de USV fueron precisas con una alta correlación con AV y un bajo sesgo de estimación (-5,9%). Además, las fórmulas prolate (sesgo= -0,75%) y elipsoide (sesgo = -3,75%) fueron confiables con un sesgo insignificante en los volúmenes estimados. Por el contrario, la fórmula de Lambert no fue confiable debido a un alto sesgo (41,6%). Para todos los métodos evaluados, se encontró que el error de estimación estaba relacionado con el tamaño del órgano (T = 3.483; p = 0.001), principalmente cuando el órgano evaluado es mayor de 50 ml. Además, se encontró que el error de estimación de forma está relacionado con la fórmula de estimación de volumen utilizada.Este estudio ha validado el USV para evaluaciones de volumen renal y esplénico al mismo tiempo que describe la fórmula de cálculo de volumen empleada, el tamaño y la forma de los órganos como contribuyentes significativos de la precisión de la estimación de volumen.


Sujet(s)
Rate/imagerie diagnostique , Échographie/méthodes , Rein/imagerie diagnostique , Taille d'organe , Rate/anatomie et histologie , Rein/anatomie et histologie
4.
Protoplasma ; 255(6): 1693-1702, 2018 Nov.
Article de Anglais | MEDLINE | ID: mdl-29752568

RÉSUMÉ

The osmeterium, found in papilionoid larvae, is an eversible organ with an exocrine gland that produces substances in response to the mechanical disturbances caused by natural enemies. The anatomy, histology and ultrastructure of the osmeterium, and the chemical composition of its secretion in Heraclides thoas (Lepidoptera: Papilionidae) were studied. Heraclides thoas larvae have a Y-shaped osmeterium in the thorax. The surface of the osmeterium has a rough cuticle lining cells with papillae and irregular folds, whereas the cells that limited the gland pores are irregular, folded, and devoid of papillae. Two types of cells are found: (i) cuticular epidermal cells on the surface of the tubular arms of the osmeterium and (ii) secretory cells of the ellipsoid gland within the region of the glandular pore. Cuticular epidermal cells show a thick cuticle, with several layers divided into epicuticle and lamellar endocuticle. Secretory cells are polygonal, with extensive folds in the basal plasma membrane that formed extracellular channels. The cytoplasm has mitochondria, ribosomes, and numerous vacuoles, whereas the nucleus is irregular in shape with decondensed chromatin. The chemical composition of the osmeterial secretion comprised (Z)-α-bisabolene (25.4%), α-bisabol (20.6%), ß-bisabolene (13.1%), (E)-α-bisabolene 8%), ß-pinene (9.91%), longipinene epoxide (8.92%), (Z)-ß-farnesene (6.96%), ß-caryophyllene (2.05%), farnesol (1.86%), linalyl propionate (1.86%), and 1-octyn-4-ol (1.07%). The morphological features suggest that the cuticular epidermal cells play a major role in the maintenance and protection of the osmeterium, whereas secretory cells are responsible for production of osmeterial secretions.


Sujet(s)
Lepidoptera , Animaux , Lepidoptera/composition chimique , Lepidoptera/croissance et développement , Lepidoptera/ultrastructure
5.
Graefes Arch Clin Exp Ophthalmol ; 255(7): 1297-1306, 2017 Jul.
Article de Anglais | MEDLINE | ID: mdl-28412772

RÉSUMÉ

PURPOSE: To investigate the correlation between the length of external limiting membrane (ELM), ellipsoid zone (EZ) and interdigitation zone (IZ) defects and visual prognosis in patients undergoing macular hole (MH) surgery, using spectral-domain optical coherence tomography (SD-OCT). METHODS: This is a retrospective, consecutive, observational case series study. Fifty-two eyes of 52 patients with primary MH were evaluated. A quantitative analysis of ELM, EZ and IZ defects was performed preoperatively and at 3 and 6 months postoperatively using SD-OCT. The correlation between pre- and postoperative ELM, EZ and IZ defects and the best-corrected visual acuity (BCVA) was investigated. RESULTS: The lengths of ELM, EZ and IZ defects correlated significantly with BCVA in each study period (P < 0.001). Preoperative measures of these band defects were also associated with visual outcomes 3 and 6 months after surgery (P < 0.05). Considering all preoperative parameters, the length of the ELM defect was the factor most strongly correlated with BCVA at 6 months (ß = 0.643, P < 0.012). The integrity of the ELM was the only factor significantly associated with BCVA at 6 months (ß = 0.427; P = 0.004). CONCLUSIONS: The preoperative length of the ELM defect is the strongest predictor of visual acuity after MH surgery. Postoperative integrity of the ELM is significantly associated with visual restoration after surgical treatment of MH.


Sujet(s)
Fossette centrale/anatomopathologie , Perforations de la rétine/diagnostic , Segment externe de cellule photoréceptrice rétinienne/anatomopathologie , Tomographie par cohérence optique/méthodes , Acuité visuelle , Sujet âgé , Femelle , Études de suivi , Humains , Mâle , Adulte d'âge moyen , Période postopératoire , Période préopératoire , Perforations de la rétine/physiopathologie , Perforations de la rétine/chirurgie , Études rétrospectives , Facteurs temps , Vitrectomie
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