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2.
Hum Reprod ; 36(6): 1711-1721, 2021 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-33889959

RESUMO

STUDY QUESTION: Does the presence of single nucleotide polymorphisms (SNPs) in the FSH receptor gene (FSHR) and/or FSH beta subunit-encoding gene (FSHB) influence ovarian response in predicted normal responders treated with rFSH? SUMMARY ANSWER: The presence of FSHR SNPs (rs6165, rs6166, rs1394205) has a statistically significant impact in ovarian response, although this effect is of minimal clinical relevance in predicted normal responders treated with a fixed dose of 150 IU rFSH. WHAT IS KNOWN ALREADY: Ovarian reserve markers have been a breakthrough in response prediction following ovarian stimulation. However, a significant percentage of patients show a disproportionate lower ovarian response, as compared with their actual ovarian reserve. Studies on pharmacogenetics have demonstrated a relationship between FSHR or FSHB genotyping and drug response, suggesting a potential effect of individual genetic variability on ovarian stimulation. However, evidence from these studies is inconsistent, due to the inclusion of patients with variable ovarian reserve, use of different starting gonadotropin doses, and allowance for dose adjustments during treatment. This highlights the necessity of a well-controlled prospective study in a homogenous population treated with the same fixed protocol. STUDY DESIGN, SIZE, DURATION: We conducted a multicenter multinational prospective study, including 368 patients from Vietnam, Belgium, and Spain (168 from Europe and 200 from Asia), from November 2016 until June 2019. All patients underwent ovarian stimulation followed by oocyte retrieval in an antagonist protocol with a fixed daily dose of 150 IU rFSH until triggering. Blood sampling and DNA extraction was performed prior to oocyte retrieval, followed by genotyping of four SNPs from FSHR (rs6165, rs6166, rs1394205) and FSHB (rs10835638). PARTICIPANTS/MATERIALS, SETTING, METHODS: Eligible were predicted normal responder women <38 years old undergoing their first or second ovarian stimulation cycle. Laboratory staff and clinicians were blinded to the clinical results and genotyping, respectively. The prevalence of hypo-responders, the number of oocytes retrieved, the follicular output rate (FORT), and the follicle to oocyte index (FOI) were compared between different FSHR and FSHB SNPs genotypes. MAIN RESULTS AND THE ROLE OF CHANCE: The prevalence of derived allele homozygous SNPs in the FSHR was rs6166 (genotype G/G) 15.8%, rs6165 (genotype G/G) 34.8%, and rs1394205 (genotype A/A) 14.1%, with significant differences between Caucasian and Asian women (P < 0.001). FSHB variant rs10835638 (c.-211 G>T) was very rare (0.5%). Genetic model analysis revealed that the presence of the G allele in FSHR variant rs6166 resulted in less oocytes retrieved when compared to the AA genotype (13.54 ± 0.46 vs 14.81 ± 0.61, estimated mean difference (EMD) -1.47 (95% CI -2.82 to -0.11)). In FSHR variant rs1394205, a significantly lower number of oocytes was retrieved in patients with an A allele when compared to G/G (13.33 ± 0.41 vs 15.06 ± 0.68, EMD -1.69 (95% CI -3.06 to -0.31)). A significantly higher prevalence of hypo-responders was found in patients with the genotype A/G for FSHR variant rs6166 (55.9%, n = 57) when compared to A/A (28.4%, n = 29), ORadj 1.87 (95% CI 1.08-3.24). No significant differences were found regarding the FORT across the genotypes for FSHR variants rs6166, rs6165, or rs1394205. Regarding the FOI, the presence of the G allele for FSHR variant rs6166 resulted in a lower FOI when compared to the A/A genotype, EMD -13.47 (95% CI -22.69 to -4.24). Regarding FSHR variant rs6165, a lower FOI was reported for genotype A/G (79.75 ± 3.35) when compared to genotype A/A (92.08 ± 6.23), EMD -13.81 (95% CI -25.41 to -2.21). LIMITATIONS, REASONS FOR CAUTION: The study was performed in relatively young women with normal ovarian reserve to eliminate biases related to age-related fertility decline; thus, caution is needed when extrapolating results to older populations. In addition, no analysis was performed for FSHB variant rs10835638 due to the very low prevalence of the genotype T/T (n = 2). WIDER IMPLICATIONS OF THE FINDINGS: Based on our results, genotyping FSHR SNPs rs6165, rs6166, rs1394205, and FSHB SNP rs10835638 prior to initiating an ovarian stimulation with rFSH in predicted normal responders should not be recommended, taking into account the minimal clinical impact of such information in this population. Future research may focus on other populations and other genes related to folliculogenesis or steroidogenesis. STUDY FUNDING/COMPETING INTEREST(S): This study was supported by an unrestricted grant by Merck Sharp & Dohme (MSD). N.P.P. reports grants and/or personal fees from MSD, Merck Serono, Roche Diagnostics, Ferring International, Besins Healthcare, Gedeon Richter, Theramex, and Institut Biochimique SA (IBSA). N.L.V. and M.T.H. report consultancy and conference fees from Merck, Ferring, and MSD, outside the submitted work. P.D. has received honoraria for lecturing and/or research grants from MSD, Ferring International, and Merck. D.S. reports grants and/or personal fees from MSD, Ferring International, Merck Serono, Cook, and Gedeon Richter. A.R.N., B.A.M., C.S., J.M., L.H.L., P.Q.M.M., H.T., and S.G. report no conflict of interests. TRIAL REGISTRATION NUMBER: NCT03007043.


Assuntos
Indução da Ovulação , Adulto , Ásia , Bélgica , Europa (Continente) , Feminino , Humanos , Estudos Prospectivos , Espanha , Vietnã
3.
J Dent Res ; 99(9): 1054-1061, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32392449

RESUMO

The use of intraoral ultrasound imaging has received great attention recently due to the benefits of being a portable and low-cost imaging solution for initial and continuing care that is noninvasive and free of ionizing radiation. Alveolar bone is an important structure in the periodontal apparatus to support the tooth. Accurate assessment of alveolar bone level is essential for periodontal diagnosis. However, interpretation of alveolar bone structure in ultrasound images is a challenge for clinicians. This work is aimed at automatically segmenting alveolar bone and locating the alveolar crest via a machine learning (ML) approach for intraoral ultrasound images. Three convolutional neural network-based ML methods were trained, validated, and tested with 700, 200, and 200 images, respectively. To improve the robustness of the ML algorithms, a data augmentation approach was introduced, where 2100 additional images were synthesized through vertical and horizontal shifting as well as horizontal flipping during the training process. Quantitative evaluations of 200 images, as compared with an expert clinician, showed that the best ML approach yielded an average Dice score of 85.3%, sensitivity of 88.5%, and specificity of 99.8%, and identified the alveolar crest with a mean difference of 0.20 mm and excellent reliability (intraclass correlation coefficient ≥0.98) in less than a second. This work demonstrated the potential use of ML to assist general dentists and specialists in the visualization of alveolar bone in ultrasound images.


Assuntos
Aprendizado de Máquina , Redes Neurais de Computação , Ultrassonografia , Neuroimagem , Reprodutibilidade dos Testes
4.
Spine (Phila Pa 1976) ; 41(5): 404-11, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26926163

RESUMO

STUDY DESIGN: Retrospective study of the coronal curvature measurement on ultrasound (US) images with the aid of previous radiographs. OBJECTIVE: To compare the reliability and accuracy of the coronal curvature measurements from US images on children who have adolescent idiopathic scoliosis (AIS) with and without the knowledge of previous radiographs. SUMMARY OF BACKGROUND DATA: Using US imaging technique to measure coronal curvature on children with AIS has demonstrated high intra- and interrater reliabilities. However, the selection of end-vertebrae and the measurement difference between radiography and the US method were only moderately reliable. METHODS: Two raters measured the coronal curvatures from 65 AIS standing US spine images, without (measured one time) and with the aid of previous standing radiographs (measured two times). The intra- and interrater reliability, the correlation and the difference between the radiographic and US measurements, and the error index of the end-vertebrae selection were assessed. RESULTS: Overall, 109 curves were investigated. The intraclass correlation coefficients (ICC) of intra- and interrater reliability of the US coronal curvature measurement with the aid of previous radiographs (AOR) were 0.95 and 0.91, respectively. In comparison with the radiographic measurements, the correlation of AOR method (R) was 0.90 and the MAD was 2.8°; the corresponding results of the US measurement without the AOR (blinded US method) were 0.73° and 4.8°, respectively. The average error index on end-vertebral selection improved 43% with the AOR. CONCLUSION: The AOR method significantly improved reliability and accuracy of the spinal curvature measurement on US images compared with the blinded US method (P<0.001). It indicates that US standing images with the AOR can be used as a reliable and accurate nonionizing imaging method to monitor children with AIS. LEVEL OF EVIDENCE: 3.


Assuntos
Radiografia/normas , Escoliose/diagnóstico por imagem , Ultrassonografia/normas , Adolescente , Criança , Feminino , Humanos , Masculino , Radiografia/métodos , Reprodutibilidade dos Testes , Estudos Retrospectivos , Método Simples-Cego , Curvaturas da Coluna Vertebral/diagnóstico por imagem , Ultrassonografia/métodos
5.
Ultrasonics ; 68: 17-28, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26894840

RESUMO

The present study investigated the accuracy of micro-scale finite element modeling for simulating broadband ultrasound propagation in water-saturated trabecular bone-mimicking phantoms. To this end, five commercially manufactured aluminum foam samples as trabecular bone-mimicking phantoms were utilized for ultrasonic immersion through-transmission experiments. Based on micro-computed tomography images of the same physical samples, three-dimensional high-resolution computational samples were generated to be implemented in the micro-scale finite element models. The finite element models employed the standard Galerkin finite element method (FEM) in time domain to simulate the ultrasonic experiments. The numerical simulations did not include energy dissipative mechanisms of ultrasonic attenuation; however, they expectedly simulated reflection, refraction, scattering, and wave mode conversion. The accuracy of the finite element simulations were evaluated by comparing the simulated ultrasonic attenuation and velocity with the experimental data. The maximum and the average relative errors between the experimental and simulated attenuation coefficients in the frequency range of 0.6-1.4 MHz were 17% and 6% respectively. Moreover, the simulations closely predicted the time-of-flight based velocities and the phase velocities of ultrasound with maximum relative errors of 20 m/s and 11 m/s respectively. The results of this study strongly suggest that micro-scale finite element modeling can effectively simulate broadband ultrasound propagation in water-saturated trabecular bone-mimicking structures.


Assuntos
Osso e Ossos , Ultrassom , Alumínio , Modelos Biológicos , Imagens de Fantasmas , Som
6.
Artigo em Inglês | MEDLINE | ID: mdl-18986934

RESUMO

Ultrasonic backscatter signals provide useful information relevant to bone tissue characterization. Trabecular bone microstructures have been considered as quasi-periodic tissues with a collection of regular and diffuse scatterers. This paper investigates the potential of a novel technique using a simplified inverse filter tracking (SIFT) algorithm to estimate mean trabecular bone spacing (MTBS) from ultrasonic backscatter signals. In contrast to other frequency-based methods, the SIFT algorithm is a time-based method and utilizes the amplitude and phase information of backscatter echoes, thus retaining the advantages of both the autocorrelation and the cepstral analysis techniques. The SIFT algorithm was applied to backscatter signals from simulations, phantoms, and bovine trabeculae in vitro. The estimated MTBS results were compared with those of the autoregressive (AR) cepstrum and quadratic transformation (QT) . The SIFT estimates are better than the AR cepstrum estimates and are comparable with the QT values. The study demonstrates that the SIFT algorithm has the potential to be a reliable and robust method for the estimation of MTBS in the presence of a small signal-to-noise ratio, a large spacing variation between regular scatterers, and a large scattering strength ratio of diffuse scatterers to regular ones.


Assuntos
Algoritmos , Osso e Ossos/diagnóstico por imagem , Osso e Ossos/fisiologia , Técnicas de Imagem por Elasticidade/métodos , Interpretação de Imagem Assistida por Computador/métodos , Animais , Bovinos , Módulo de Elasticidade , Estresse Mecânico
7.
Stud Health Technol Inform ; 140: 151-6, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18810018

RESUMO

The Cobb angle method is the gold standard to assess severity of scoliosis. A computer-aided method was developed to provide a semi-automatic Cobb angle measurement during a scoliosis clinic. This study was to evaluate the reliability and accuracy of the developed method. Curve types were also tested. The computer method required enhancement of the contrast, normalization of the image size, and selection of the end-vertebrae on the radiographs before the automatic measurement started. The computer-aided process automatically identified the line segments that fitted to the endplates of the end-vertebrae. The Cobb angle was then calculated from the slopes of these lines. Seventy-six radiographs were randomly selected and categorized with Lenke's classification. Among them, 75 cases were used and categorized into 4 types: 1, 3, 5 and 6. One type 2 case was excluded. An orthopedic spine surgeon measured the radiographs manually, serving as the reference standard. Two observers used the developed method and measured twice. For each curve type, the inter-method, inter-observer, and intra-observer variability were analyzed by Intraclass correlation coefficients (ICC[2,1]). The ICC values were higher than 0.90 in all these types. The developed method was reliable to measure the Cobb angle and was not dependent on the curve type.


Assuntos
Processamento de Imagem Assistida por Computador/instrumentação , Escoliose/diagnóstico por imagem , Curvaturas da Coluna Vertebral/diagnóstico por imagem , Humanos , Projetos Piloto , Radiografia , Valores de Referência , Reprodutibilidade dos Testes , Escoliose/patologia , Curvaturas da Coluna Vertebral/patologia
8.
Int J Gynecol Cancer ; 15(5): 799-806, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16174227

RESUMO

The results of a multicenter phase II study investigating carboplatin and pegylated liposomal doxorubicin (PLD) in patients with recurrent/metastatic uterine and cervical malignancies (UCM) are presented here. Fifty-three subjects with measurable, untreated, advanced UCM were enrolled. Fifty-one were evaluable for response. Prior combined-modality treatment was permitted if a component of primary therapy. Patients received carboplatin AUC = 5 with PLD 35 mg/m(2) intravenously once every 4 weeks. Overall response rate was 33% (35% stable disease). Overall survival (OS) at six months was 86% (95% CI 76%-96%). Six-month progression-free survival (PFS) was 43% (95% CI 30%-57%). Median PFS was 22.9 weeks (range 16.0-35.3) and median OS was 49.1 weeks (range 41.4-75.1). The most frequent grade 3-4 nonhematological adverse events were: abdominal pain (n = 7), fatigue (4), vomiting (4), nausea (3), and shortness of breath (3). There was 1 report of grade 3 hand-foot syndrome and none of grade 4. Twelve patients had first infusion reactions with only 1 discontinuing treatment. Grade 3-4 neutropenia occurred in 26/230 cycles (11.3%). There were no treatment-related deaths. The combination of carboplatin and PLD is well tolerated with sufficient activity to justify additional evaluation in clinical trials and might be suited to the addition of a taxane.


Assuntos
Carboplatina/uso terapêutico , Doxorrubicina/análogos & derivados , Doxorrubicina/uso terapêutico , Polietilenoglicóis/uso terapêutico , Neoplasias Uterinas/tratamento farmacológico , Adolescente , Adulto , Contagem de Células Sanguíneas , Carboplatina/efeitos adversos , Doxorrubicina/efeitos adversos , Quimioterapia Combinada , Feminino , Humanos , Polietilenoglicóis/efeitos adversos , Taxa de Sobrevida
9.
South Med J ; 92(12): 1204-6, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10624915

RESUMO

We describe the case of an adolescent girl who had an isolated cranial sternal cleft without any associated abnormalities; the cleft had been well tolerated since her birth. A review of the literature shows that such cases are uncommon. In such cases, surgery is only for cosmetic reasons.


Assuntos
Anormalidades Múltiplas , Esterno/anormalidades , Adolescente , Feminino , Humanos , Índice de Gravidade de Doença
10.
South Med J ; 91(12): 1169-72, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9853734

RESUMO

Mediastinal lipomatosis is a benign condition characterized by a large amount of mature adipose tissue within the mediastinum. It widens the mediastinum and may simulate mass lesions, thus leading to diagnostic errors. We describe a new case of a huge mediastinal lipomatosis and review 36 cases previously reported in the literature. Computed tomography has an important role in the diagnosis of this disease. To avoid invasive and unnecessary procedures, this diagnosis should be considered in any patient with Cushing's syndrome.


Assuntos
Lipomatose/diagnóstico por imagem , Doenças do Mediastino/diagnóstico por imagem , Tecido Adiposo/diagnóstico por imagem , Adulto , Cardiomegalia/diagnóstico , Síndrome de Cushing/diagnóstico , Diagnóstico Diferencial , Humanos , Masculino , Tomografia Computadorizada por Raios X
11.
Phys Med Biol ; 43(8): 2295-308, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9725605

RESUMO

Berlage wavelets are used to simulate ultrasonic pulses in an unbounded, homogeneous, isotropic and absorptive medium. Intrinsic absorption of the medium is properly described by Kolsky's attenuation, which considers velocity dispersion to meet the causality condition. Several current time-domain velocity measurement techniques have been investigated using numerically simulated pulses for three normalized BUA values: 20, 40 and 60 dB MHz(-1) cm(-1), which mimic experimentally determined values for cancellous bone. The velocities, calculated using first motion transit times, are used as references supported by the Fermat principle of least time. The simulated results for fixed sample thickness indicate that pulse-broadening increases with the transit time of the reference point and the intrinsic absorption of the medium. Comparison shows that the first zero-crossing method yields 3-6% errors in velocity results, better than the cross-correlation method. However, the zero-crossing method gives inconsistent velocity measurement for a medium of 40 dB MHz(-1) cm(-1)1 absorption and three different thicknesses: 0.2, 0.4 and 0.6 cm. A novel technique for velocity measurement is presented using the peak of the envelope of a signal as a reference point to measure transit time difference. The envelope of a signal represents the instantaneous amplitude of the associated analytic signal. The velocities derived using this method differ from the true velocities by only 1.2-2.4%, more accurate than those obtained by the first zero-crossing method. The envelope peak has the additional merits of easy detection and robustness. Most importantly, the envelope technique may be used to yield accurate velocity measurement in cases where an accurate determination of the first motion transit time is sometimes prohibited due to the presence of noise.


Assuntos
Osso e Ossos/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Ultrassonografia/métodos , Simulação por Computador , Humanos
12.
Rev Pneumol Clin ; 54(5): 264-7, 1998 Oct.
Artigo em Francês | MEDLINE | ID: mdl-9894282

RESUMO

Endobronchial lipoma is an uncommon benign tumor. It is composed of fat tissue and is visible on CT scanner. We report an unusual case of a patient who developed two endobronchial lipomas. The first lipoma was removed 10 years earlier. We emphasize the contribution of computed tomography in the diagnosis of endobronchial lipoma. Cases of multiple lipomas are very scarce in the literature.


Assuntos
Neoplasias Brônquicas , Lipoma , Segunda Neoplasia Primária , Neoplasias Brônquicas/diagnóstico por imagem , Neoplasias Brônquicas/cirurgia , Feminino , Humanos , Lipoma/diagnóstico por imagem , Lipoma/cirurgia , Pessoa de Meia-Idade , Segunda Neoplasia Primária/diagnóstico por imagem , Pneumonectomia , Fatores de Tempo , Tomografia Computadorizada por Raios X
13.
Phys Med Biol ; 42(4): 757-8, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9127451

RESUMO

The amplitude acoustic reflection coefficient of an interface between two lossy biological tissues can be approximated as Rlossy approximately Rlossless + i delta/2 where Rlossless is the lossless acoustic reflection coefficient and delta is the change in alpha/kappa (absorption coefficient per wavenumber) across the tissue interface. This approximation is shown to be valid for both normal and oblique angles of incidence.


Assuntos
Modelos Teóricos , Ultrassonografia/métodos , Acústica , Reprodutibilidade dos Testes
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