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1.
Trop Anim Health Prod ; 55(2): 119, 2023 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-36930426

RESUMO

Considering the economic and commercial efficiency of the beef production chain, the yield and quality of the meat produced must also be included in breeding programs. For the Nellore breed, including the polled herd, these aspects have not been much studied. The aim of this study was to estimate genetic parameters for scrotal circumference adjusted to 365 (SC365) and 450 (SC450) days of age, age at first calving (AFC), accumulated productivity (AP), stayability (STAY), longissimus muscle area (LMA), thickness of subcutaneous fat over the 12th-13th ribs (BF), thickness of subcutaneous fat over the rump (RF), and shear force measured by Warner-Bratzler shear force (WBSF) of polled Nellore cattle. Bayesian analyses were performed by adopting a linear animal model, whereas STAY analyses used the linear threshold model. Heritability estimates were 0.31 (SC365), 0.37 (SC450), 0.16 (AFC), 0.25 (AP), 0.16 (STAY), 0.30 (LMA), 0.13 (BF), 0.24 (RF), and 0.15 (WBSF), indicating moderate response to selection. Genetic and residual correlations between SC365 and SC450 were high (0.91 and 0.74, respectively), as well as the genetic correlations of AP with SC365, SC450, AFC, and STAY (0.61, 0.62, - 0.69, and 0.83, respectively). Genetic and residual correlations of WBSF with reproductive and carcass characteristics exhibited high standard deviations, however favorable. Based on the results, it is expected that in the medium term, animals with greater sexual precocity will also have greater accumulated productivity and longer permanence of females in the herd, along with superior carcass traits. However, due to the low heritabilities and small genetic associations with reproductive traits, fat thickness characteristics (BF and RF) will still require direct selection.


Assuntos
Carne , Reprodução , Animais , Bovinos/genética , Feminino , Teorema de Bayes , Fenótipo , Reprodução/genética
2.
BMC Bioinformatics ; 23(1): 438, 2022 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-36266626

RESUMO

Recently, Deep Learning based automatic generation of treatment recommendation has been attracting much attention. However, medical datasets are usually small, which may lead to over-fitting and inferior performances of deep learning models. In this paper, we propose multi-objective data enhancement method to indirectly scale up the medical data to avoid over-fitting and generate high quantity treatment recommendations. Specifically, we define a main and several auxiliary tasks on the same dataset and train a specific model for each of these tasks to learn different aspects of knowledge in limited data scale. Meanwhile, a Soft Parameter Sharing method is exploited to share learned knowledge among models. By sharing the knowledge learned by auxiliary tasks to the main task, the proposed method can take different semantic distributions into account during the training process of the main task. We collected an ultrasound dataset of thyroid nodules that contains Findings, Impressions and Treatment Recommendations labeled by professional doctors. We conducted various experiments on the dataset to validate the proposed method and justified its better performance than existing methods.


Assuntos
Aprendizado Profundo , Redes Neurais de Computação , Projetos de Pesquisa , Conhecimento
3.
Neuromuscul Disord ; 32(9): 754-762, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35902324

RESUMO

Fukuyama-type congenital muscular dystrophy (FCMD) is severe, childhood-onset muscular dystrophy. Recently, our group has discovered a potential treatment using antisense oligonucleotides. Therefore, an effective, reliable, and objective method of assessing muscle is needed. Ultrasound is a minimally invasive tool that can be applied without radiation exposure or pain. Evaluating tissue stiffness by shear wave elastography (SWE) has especially recently attracted attention. Here, we aimed to evaluate SWE value of the upper limb muscles: biceps brachii, triceps brachii, brachioradialis, abductor pollicis brevis, and abductor finger muscle in patients with FCMD. Upper extremity function was evaluated by visual muscle ultrasound analysis (VMUA) and SWE in 13 patients with FCMD and 20 healthy controls. The motor function evaluation tool was used to evaluate motor function, and the correlation with the dynamics of the SWE was determined. VMUA scaled using the Heckmatt scale was higher in patients with FCMD. SWE was also significantly higher and stiffer in the biceps brachii and brachioradialis in patients with FCMD. Furthermore, the severity of FCMD symptoms was correlated with muscle stiffness. We conclude that VMUA and SWE can be useful tools for monitoring muscle atrophy and upper limb function in patients with FCMD.


Assuntos
Técnicas de Imagem por Elasticidade , Distrofias Musculares , Síndrome de Walker-Warburg , Braço , Criança , Técnicas de Imagem por Elasticidade/métodos , Humanos , Músculo Esquelético/diagnóstico por imagem , Músculo Esquelético/fisiologia , Distrofias Musculares/congênito , Oligonucleotídeos Antissenso
4.
J Exp Biol ; 224(16)2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34296753

RESUMO

In this study, we used kinematic, kinetic, metabolic and ultrasound analysis to investigate the role of elastic energy utilization on the mechanical and physiological demands of a movement task (hopping) that primarily involves the plantar-flexor muscles to determine the contribution of tendon work to total mechanical work and its relationship with apparent efficiency (AE) in bouncing gaits. Metabolic power (PMET) and (positive) mechanical power at the whole-body level (PMEC) were measured during hopping at different frequencies (2, 2.5, 3 and 3.5 Hz). The (positive) mechanical power produced during the Achilles tendon recoil phase (PTEN) was obtained by integrating ultrasound data with an inverse dynamic approach. As a function of hopping frequency, PMEC decreased steadily and PMET exhibited a U-shape behaviour, with a minimum at about 3 Hz. AE (PMEC/PMET) showed an opposite trend and was maximal (about 0.50) at the same frequency when PTEN was also highest. Positive correlations were observed: (i) between PTEN and AE (AE=0.22+0.15PTEN, R2=0.67, P<0.001) and the intercept of this relationship indicates the value of AE that should be expected when tendon work is nil; (ii) between AE and tendon gearing (Gt=Δmuscle-tendon unit length/Δmuscle belly length; R2=0.50, P<0.001), where a high Gt indicates that the muscle is contracting more isometrically, thus allowing the movement to be more economical (and efficient); (iii) between Gt and PTEN (R2=0.73, P<0.001), which indicates that Gt could play an important role in the tendon's capability to store and release mechanical power.


Assuntos
Tendão do Calcâneo , Fenômenos Biomecânicos , Marcha , Movimento , Músculo Esquelético
5.
Fetal Diagn Ther ; 47(8): 636-641, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32653881

RESUMO

INTRODUCTION: Prelabor rupture of membranes (PROM) is a frequent clinical situation, and the decision about the best time for delivery remains controversial, mainly due to the risk of neonatal respiratory morbidity (NRM). Assessment of fetal lung maturity using ultrasound, a safe method and widely used in current obstetrical practice, could change this scenario. This study was designed to evaluate the ability of quantitative ultrasound method QuantusFLM® to predict NRM in patients with PROM and whether maternal BMI, gestational age, occurrence of the disease, and presence of oligohydramnios influenced the performance. METHODS: Patients with singleton gestations, diagnosis of PROM, and gestational age between 24 and 38 weeks and 6 days were included. Fetal lung image was acquired by ultrasound within 48 h prior to delivery and analyzed by QuantusFLM®. The results were then paired with neonatal outcomes to assess the program's ability to predict the NRM in this specific group. A logistic regression model was created to analyze factors that could affect the test results. RESULTS: Fifty-four patients were included. Mean maternal BMI was 28.99 kg/m2, and in 25 patients (46.2%), oligohydramnios was observed at the time of examination. Mean gestational age at delivery was 35 weeks and 4 days, and the NRM prevalence was of 18.5%. QuantusFLM® predicted NRM with a 60% sensitivity, 79.5% specificity, 40% positive predictive value, 89.7% negative predictive value, and 75.6% accuracy. Maternal BMI, disease occurrence, presence of oligohydramnios, and gestational age did not interfere with the evaluation. CONCLUSION: This study demonstrates a good accuracy of QuantusFLM® as a NRM predictor in patients with PROM, with particular reliability in identifying that pulmonary maturity has already occurred.


Assuntos
Ruptura Prematura de Membranas Fetais/diagnóstico por imagem , Pulmão/diagnóstico por imagem , Síndrome do Desconforto Respiratório do Recém-Nascido/diagnóstico por imagem , Adulto , Líquido Amniótico/diagnóstico por imagem , Feminino , Maturidade dos Órgãos Fetais , Humanos , Recém-Nascido , Pessoa de Meia-Idade , Gravidez , Estudos Prospectivos , Ultrassonografia Pré-Natal
6.
Ultrasound Med Biol ; 46(2): 455-459, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31753599

RESUMO

A native arteriovenous fistula (AVF) is the vascular access of choice for hemodialysis (HD) treatment. Compared with other types of vascular access such as grafts and central venous catheters, it functions longer and is associated with a lower risk of complications. The aim of the study described here was to assess, in an HD population, the position of the fistula needles during an HD session and evaluate the role of ultrasound in the management of AVF puncture. Forty-five consecutive chronic HD patients with an AVF or an arteriovenous vascular graft were included in the study for ultrasound evaluation. Each patient underwent an ultrasound evaluation during HD treatment to assess the position of the needles inside the vascular access. The ultrasound evaluation revealed that 81.8% of the traditional needles were incorrectly adjacent to the vessel walls, in the absence of clinical symptoms or hemodynamic alterations detectable on the dialysis monitor. A greater frequency of malpositioning has been observed for needles in the arterial portion of the vascular access, closer to the anastomosis. The absence of clinically detectable signs of venipuncture-related complications does not ensure correct positioning of the needles within the AVF. Ultrasound evaluation may not only resolve suboptimal cannulation problems of new or complicated vascular accesses but may also be useful in the prevention of acute and chronic damage to the AVF.


Assuntos
Derivação Arteriovenosa Cirúrgica/métodos , Cateterismo/instrumentação , Cateterismo/métodos , Diálise Renal , Cirurgia Assistida por Computador , Ultrassonografia de Intervenção , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Agulhas
7.
Sensors (Basel) ; 19(11)2019 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-31159334

RESUMO

This study presents a platform for ex-vivo detection of cancer nodules, addressing automation of medical diagnoses in surgery and associated histological analyses. The proposed approach takes advantage of the property of cancer to alter the mechanical and acoustical properties of tissues, because of changes in stiffness and density. A force sensor and an ultrasound probe were combined to detect such alterations during force-regulated indentations. To explore the specimens, regardless of their orientation and shape, a scanned area of the test sample was defined using shape recognition applying optical background subtraction to the images captured by a camera. The motorized platform was validated using seven phantom tissues, simulating the mechanical and acoustical properties of ex-vivo diseased tissues, including stiffer nodules that can be encountered in pathological conditions during histological analyses. Results demonstrated the platform's ability to automatically explore and identify the inclusions in the phantom. Overall, the system was able to correctly identify up to 90.3% of the inclusions by means of stiffness in combination with ultrasound measurements, paving pathways towards robotic palpation during intraoperative examinations.


Assuntos
Neoplasias/diagnóstico por imagem , Robótica , Animais , Humanos , Ultrassonografia
8.
Adv Wound Care (New Rochelle) ; 6(11): 383-391, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-29098114

RESUMO

Objective: High-frequency ultrasound (HFUS) images are being researched for use in the prevention, detection, and monitoring of pressure injuries in patients at risk. This seminal longitudinal study in mechanically ventilated adults describes image quality, the incidence of image artifacts, and their effect on image quality in critically ill subjects. Approach: Mechanically ventilated subjects from three adult intensive care units were enrolled, and multiple sacral images from each subject were obtained daily. Using a subset of best image per patient per day, artifacts were grouped, and their effect on image quality was statistically evaluated. Results: Of a total of 1761 images collected from 137 subjects, 8% were rated as poor. In the subset, 70% had good quality ratings. Four groups of artifacts were identified as follows: "bubbles," "texture problems," "layer nondifferentiation," and "reduced area for evaluation." Artifacts from at least one group were found in 83% of images. Bubbles were most frequently seen, but artifacts with adverse effect on image quality were "layer nondifferentiation," "texture problems," and "reduced area for evaluation." Innovation: HFUS image evaluation is still in the development phase with respect to tissue injury use. Artifacts are generally omnipresent. Quickly recognizing artifacts that most significantly affect image quality during scanning will result in higher quality images for research and clinical applications. Conclusion: Good quality images were achievable in study units; although frequent artifacts were present in images, in general, they did not interfere with evaluation. Artifacts related to "layer nondifferentiation" was the greatest predictor of poor image quality, prompting operators to immediately rescan the area.

9.
Skin Res Technol ; 22(2): 137-47, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26075836

RESUMO

BACKGROUND: Concepts of beauty are more and more globalised leading to the homogenisation of the physical appearance. It is therefore important to identify morphological characteristics of ethnic groups. We compare faces from Chinese and Caucasian women, identify morphological differences that were not documented yet and study the influence of BMI on these differences. METHODS: The study was carried on groups of 60 women: a Chinese and a Caucasian group. Both included two equal sub-groups: normal BMI and higher BMI. Face widths were measured from individual pictures and from reconstructed average faces obtained using a new reconstruction algorithm. Cheek/chin and neck/chin angles were determined from individual pictures. Topography of the cheekbone and temple face was determined by fringe projection technique. Ultrasound analysis allows measurements of hypodermis thickness. RESULTS: Our innovative average face reconstruction algorithm produced images of a yet unequalled quality with width characteristics similar to those of individual pictures. Analysis shows that faces of Chinese women are larger and rounder. They present other differences that were so far unidentified. Finally, overweight impacts differently Chinese and Caucasian women faces and has greater influence on Chinese women faces.


Assuntos
Povo Asiático/estatística & dados numéricos , Índice de Massa Corporal , Cefalometria/métodos , Face/anatomia & histologia , Pele/anatomia & histologia , População Branca/estatística & dados numéricos , Adulto , Face/fisiologia , Feminino , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Fotografação/métodos , Valores de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Fenômenos Fisiológicos da Pele
10.
Nephrology (Carlton) ; 21(2): 97-107, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26058976

RESUMO

AIM: Nephrocalcinosis is a clinical-pathological entity characterized by the deposition of calcium salts within the kidney parenchyma. Both the protean presentation and multiple causes may explain the lack of data regarding its prevalence. The aim of this study is to report the prevalence and main clinical features of nephrocalcinosis diagnosed in a newly opened nephrology outpatient unit. METHODS: Analysis on the data we prospectively gathered from the start of activity (2007-2013) was carried out. Clinical and laboratory data were collected from the medical records and from the general laboratory; diagnosis was based upon imaging data reviewed by the same radiologists. RESULTS: Sixty-five of 2695 patients referred to our unit were diagnosed with nephrocalcinosis (2.4%). The affected patients were younger than the overall out-patient population (median: 37.7 (min-max: 8-82) vs 63 years (2-102) P < 0.001), with higher female prevalence (68% vs 51.4%: P < 0.05) and better preserved kidney function (CKD-EPI 103 (23-165) vs 60 mL/min (3.2-169) P < 0.001). Kidney stones were the main reason for referral (35.4%), followed by electrolyte disturbances (22.7%), acute pyelonephritis (4.6%), AKI or CKD (4.6%). Nephrocalcinosis was associated with autoimmune diseases in 29% and with microcythaemia in 23%, while positive family history was present in 23% of patients. Various electrolyte disturbances were observed, with hypercalciuria being the hallmark of beta thalassaemic patients. CONCLUSIONS: Nephrocalcinosis is a rare, but not exceptional disease in nephrology. In Mediterranean countries, microcythaemia would appear to be a major cause of this disease. Greater awareness of nephrocalcinosis is needed for an integrated approach involving various branches of internal medicine and radiology.


Assuntos
Nefrocalcinose/epidemiologia , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Doenças Autoimunes/epidemiologia , Criança , Feminino , Predisposição Genética para Doença , Hereditariedade , Humanos , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Nefrocalcinose/diagnóstico por imagem , Nefrocalcinose/terapia , Nefrologia , Ambulatório Hospitalar , Prevalência , Encaminhamento e Consulta , Estudos Retrospectivos , Fatores de Risco , Distribuição por Sexo , Talassemia/epidemiologia , Fatores de Tempo , Adulto Jovem
11.
Thromb Haemost ; 113(6): 1357-69, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25809056

RESUMO

Ultrasound and microbubble (MB) contrast agents accelerate clot lysis, yet clinical trials have been performed without defining optimal acoustic conditions. Our aim was to assess the effect of acoustic pressure and frequency on the extent and spatial location of clot lysis. Clots from porcine blood were created with a 2-mm central lumen for infusion of lipid-shelled perfluorocarbon MBs (1×10(7) ml(-1)) or saline. Therapeutic ultrasound at 0.04, 0.25, 1.05, or 2.00 MHz was delivered at a wide range of peak rarefactional acoustic pressure amplitudes (PRAPAs). Ultrasound was administered over 20 minutes grouped on-off cycles to allow replenishment of MBs. The region of lysis was quantified using contrast-enhanced ultrasound imaging. In the absence of MBs, sonothrombolysis did not occur at any frequency. Sonothrombolysis was also absent in the presence of MBs despite their destruction at 0.04 and 2.00 MHz. It occurred at 0.25 and 1.05 MHz in the presence of MBs for PRAPAs > 1.2 MPa and increased with PRAPA. At 0.25 MHz the clot lysis was located in the far wall. At 1.05 MHz, however, there was a transition from far to near wall as PRAPA was increased. The area of clot lysis measured by ultrasound imaging correlated with that by micro-CT and quantification of debris in the effluent. In conclusion, sonothrombolysis with MBs was most efficient at 0.25 MHz. The spatial location of sonothrombolysis varies with pressure and frequency indicating that the geometric relation between therapeutic probe and vascular thrombosis is an important variable for successful lysis clinically.


Assuntos
Meios de Contraste , Trombólise Mecânica/métodos , Microbolhas , Trombose/terapia , Terapia por Ultrassom/métodos , Animais , Desenho de Equipamento , Masculino , Trombólise Mecânica/instrumentação , Pressão , Som , Suínos , Trombose/sangue , Trombose/diagnóstico por imagem , Fatores de Tempo , Transdutores , Terapia por Ultrassom/instrumentação , Ultrassonografia , Microtomografia por Raio-X
12.
Ciênc. rural ; 45(2): 317-322, 02/2015. tab, graf
Artigo em Português | LILACS | ID: lil-732375

RESUMO

Objetivou-se estimar as herdabilidades para as características de carcaça de área de olho de lombo (AOL), espessura de gordura subcutânea (EG) e espessura de gordura subcutânea na garupa (EGP8), medidas por ultrassonografia, em bovinos da raça Nelore Mocho, criados em bioma Cerrado. As informações utilizadas foram provenientes de criatórios da raça Nelore Mocho, participantes do Programa Nelore Brasil, da Associação Nacional de Criadores e Pesquisadores (ANCP), localizados nos estados que representam as maiores áreas contínuas do bioma Cerrado. As estimativas de herdabilidade foram obtidas mediante análises bi-características, sob modelo animal, utilizando a estatística bayesiana por meio do aplicativo MTGSAM. As estimativas de herdabilidade foram de média magnitude para a AOL (0,25), EG (0,19) e EGP8 (0,25). Os resultados obtidos sugerem que as características de carcaça, avaliadas por ultrassonografia, apresentam grande variabilidade genética e podem ser incluídas em programas de melhoramento genético de bovinos da raça Nelore Mocho.


The purpose of this study was to estimate the genetic parameters for carcass traits of longissimus muscle area (LMA), backfat thickness (BF) and rump fat thickness (RF), measured by ultrasound in Polled Nelore cattle raised in the Cerrado biome. The data set was obtained from bovines Polled Nelore, proceeding from participant farms of the Nelore Brazil Program of the National Association of Breeders and Researchers, raised on pasture, from the Brazilian states that have the largest continuous areas of the Cerrado. Heritabilities were estimated by Gibbs Sampling using the MTGSAM software (Multiple Trait using Gibbs Sampler under Animal Model). The heritability estimates were 0.30, 0.17 and 0.25 for LMA, BF and RF, respectively. The results indicate that carcass traits have high genetic variability and should be included in breeding programs.

13.
Thromb Haemost ; 112(6): 1129-36, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25104514

RESUMO

After a proximal deep-vein thrombosis (P-DVT), the risk of diagnosis of a previously unsuspected cancer is high. Isolated distal DVT (iD-DVT; i.e. infra-popliteal DVT without pulmonary embolism [PE]) and isolated superficial-vein thrombosis (iSVT; i.e. without concomitant DVT and PE) are at least as frequent as P-DVT but their association with subsequent cancer is uncertain. We exploited data from the OPTIMEV prospective, observational, multicentre study to i) compare the risk of subsequent cancer three years after a first objectively confirmed iSVT, iD-DVT and iP-DVT in patients without a prior history of cancer or of venous thromboembolism, ii) assess predictors of subsequent cancer in cases of iD-DVT. The overall cumulative rates of cancer among the 304 patients with iSVT, 536 patients with iD-DVT, and 327 patients with iP-DVT were similar (3.4% 95% confidence interval [1.8-6.2], 3.9% [2.5-5.9] and 3.9% [2.3-6.8], respectively), regardless of whether the index venous thromboembolic event was unprovoked or associated with a major transient risk factor. Neither anatomical (muscular vs deep-calf DVT) nor ultrasound scan characteristics (number of thrombosed veins, clot diameter under compression) seemed strongly associated with the risk of cancer in cases of iD-DVT. In patients managed in routine practice, all the different clinical expressions of lower limb venous thromboembolism are associated with a similar risk of subsequent cancer. From a clinical practice point of view, this suggests that cancer screening, without discussing the necessity, or not, of such screening, should not differ between a deep-proximal, deep-distal or superficial location of thrombosis.


Assuntos
Extremidade Inferior/irrigação sanguínea , Neoplasias/epidemiologia , Trombose Venosa/epidemiologia , Idoso , Causas de Morte , Feminino , França/epidemiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Neoplasias/diagnóstico , Neoplasias/mortalidade , Prognóstico , Estudos Prospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo , Ultrassonografia , Trombose Venosa/diagnóstico por imagem , Trombose Venosa/mortalidade , Trombose Venosa/terapia
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