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1.
J Int Med Res ; 49(2): 300060521991023, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33596690

RESUMO

OBJECTIVE: Traditional approaches that involve measuring the height and volume of the pituitary by magnetic resonance imaging (MRI) are unreliable. We investigated the use of a more accurate method using texture analysis to evaluate idiopathic central precocious puberty (ICPP) by MRI. METHODS: In total, 352 texture features of the pituitary were extracted from 12 healthy girls and 18 girls with ICPP. A LASSO regression model and linear regression model were used to create the prediction model. Pearson's correlation analysis and receiver operating characteristic curves were used to evaluate the predictive performance. RESULTS: The radiomics score had a significant linear relationship with the luteinizing hormone concentration and the luteinizing hormone/follicle-stimulating hormone ratio. The radiomics score showed better predictive performance than traditional pituitary measurements. The area under the curve of the radiomics score, pituitary height, and variable combinations was 0.759 (95% confidence interval [CI], 0.583-0.936), 0.681 (95% CI, 0.483-0.878), and 0.829 (95% CI, 0.681-0.976), respectively. CONCLUSION: Combination of the radiomics score with pituitary height measurements allows for better evaluation of the pituitary during diagnostic imaging, indicating satisfactory potential for efficacy assessments.

2.
Brain Imaging Behav ; 2021 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-33537928

RESUMO

The amygdala is an important part of the medial temporal lobe and plays a pivotal role in the emotional and cognitive function. The aim of this study was to build and validate comprehensive classification models based on amygdala radiomic features for Alzheimer's disease (AD) and amnestic mild cognitive impairment (aMCI). For the amygdala, 3360 radiomic features were extracted from 97 AD patients, 53 aMCI patients and 45 normal controls (NCs) on the three-dimensional T1-weighted magnetization-prepared rapid gradient echo (MPRAGE) images. We used maximum relevance and minimum redundancy (mRMR) and least absolute shrinkage and selection operator (LASSO) to select the features. Multivariable logistic regression analysis was performed to build three classification models (AD-NC group, AD-aMCI group, and aMCI-NC group). Finally, internal validation was assessed. After two steps of feature selection, there were 5 radiomic features remained in the AD-NC group, 16 features remained in the AD-aMCI group and the aMCI-NC group, respectively. The proposed logistic classification analysis based on amygdala radiomic features achieves an accuracy of 0.90 and an area under the ROC curve (AUC) of 0.93 for AD vs. NC classification, an accuracy of 0.81 and an AUC of 0.84 for AD vs. aMCI classification, and an accuracy of 0.75 and an AUC of 0.80 for aMCI vs. NC classification. Amygdala radiomic features might be early biomarkers for detecting microstructural brain tissue changes during the AD and aMCI course. Logistic classification analysis demonstrated the promising classification performances for clinical applications among AD, aMCI and NC groups.

3.
Andrology ; 2020 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-33150723

RESUMO

BACKGROUND: The coronavirus disease 2019 (COVID-19) has been spreading all over the world since December 2019. However, medical information regarding the urogenital involvement in recovered COVID-19 patients is limited or unknown. OBJECTIVES: To comprehensively evaluate urogenital involvement in recovered COVID-19 patients. MATERIALS AND METHODS: Men aged between 20 years and 50 years who were diagnosed with SARS-CoV-2 infection and recovered when the study was conducted were enrolled in our study. Demographic and clinical characteristics, and history of hospitalization were collected and analyzed. Urine, expressed prostatic secretions (EPSs), and semen samples were collected for SARS-CoV-2 RNA detection. Semen quality and hormonal profiles were analyzed. RESULTS: Among 74 male recovered COVID-19 patients, 11 (14.9%) were asymptomatic, classified into mild type, and 31 (41.9%) were classified into moderate type. The remaining patients (32/74, 43.2%) had severe pneumonia. No critically ill recovered COVID-19 patient was recruited in our cohort. The median interval between last positive pharyngeal swab RT-PCR test and semen samples collection was 80 days (IQR, 64-93). The median age was 31 years (IQR, 27-36; range, 21-49), and the median body mass index (BMI) was 24.40 (IQR, 22.55-27.30). Forty-five (61.6%) men were married, and 28 (38.4%) were unmarried. Fifty-three (72.6%) patients denied cigarette smoking, 18 (24.7%) were active smokers, and 2 of them were past smokers. The majority of our participants (53/74, 72.6%) did not consume alcohol. Fever occurred in most of the patients (75.3%), and 63 of them had abnormal chest CT images. Only one patient complained of scrotal discomfort during the course of COVID-19, which was ruled out orchitis by MRI (data not shown). A total of 205 samples were collected for SARS-CoV-2 detection (74 urine samples, 70 semen samples, and 61 EPS samples). However, viral nucleic acid was not detected in body fluids from the urogenital system. In terms of hormonal profiles, the levels of FSH, LH, testosterone, and estradiol were 5.20 [4.23] mIU/mL, 3.95 [1.63] mIU/mL, 3.65 [1.19] ng/mL, and 39.48 [12.51] pg/mL, respectively. And these values were within the normal limits. The overall semen quality of recovered COVID-19 patients was above the lower reference limit released by the WHO. While compared with healthy control, sperm concentration, total sperm count, and total motility were significantly declined. In addition, different clinical types of COVID-19 have no significant difference in semen parameters, but total sperm count showed a descending trend. Interestingly, subjects with a longer recovery time showed worse data for sperm quality. Small sample size and lacking semen parameters before the infection are the major limitations of our study. DISCUSSION AND CONCLUSIONS: To the best of our knowledge, it is the largest cohort study with longest follow-up for urogenital evaluation comprehensively so far. Direct urogenital involvement was not found in the recovered COVID-19 male patients. SARS-CoV-2 RNA was undetectable in the urogenital secretions, and semen quality declined slightly, while hormonal profiles remained normal. Moreover, patients with a long time (≥90 days) since recovery had lower total sperm count. Great attention and further study should be conducted and follow-up on the reproductive function in the following months.

5.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 1560-1563, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018290

RESUMO

The characteristics of diabetic retinopathy (DR) fundus images generally consist of multiple types of lesions which provided strong evidence for the ophthalmologists to make diagnosis. It is particularly significant to figure out an efficient method to not only accurately classify DR fundus images but also recognize all kinds of lesions on them. In this paper, a deep learning-based multi-label classification model with Gradient-weighted Class Activation Mapping (Grad-CAM) was proposed, which can both make DR classification and automatically locate the regions of different lesions. To reducing laborious annotation work and improve the efficiency of labeling, this paper innovatively considered different types of lesions as different labels for a fundus image so that this paper changed the task of lesion detection into that of image classification. A total of five labels were pre-defined and 3228 fundus images were collected for developing our model. The architecture of deep learning model was designed by ourselves based on ResNet. Through experiments on the test images, this method acquired a sensitive of 93.9% and a specificity of 94.4% on DR classification. Moreover, the corresponding regions of lesions were reasonably outlined on the DR fundus images.


Assuntos
Aprendizado Profundo , Diabetes Mellitus , Retinopatia Diabética , Retinopatia Diabética/diagnóstico por imagem , Fundo de Olho , Humanos , Sensibilidade e Especificidade
6.
Front Neurosci ; 14: 708, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32733197

RESUMO

Malignant middle cerebral artery infarction (mMCAi) is a serious complication of cerebral infarction usually associated with poor patient prognosis. In this retrospective study, we analyzed clinical information as well as non-contrast computed tomography (NCCT) and computed tomography angiography (CTA) data from patients with cerebral infarction in the middle cerebral artery (MCA) territory acquired within 24 h from symptoms onset. Then, we aimed to develop a model based on the radiomics signature to predict the development of mMCAi in cerebral infarction patients. Patients were divided randomly into training (n = 87) and validation (n = 39) sets. A total of 396 texture features were extracted from each NCCT image from the 126 patients. The least absolute shrinkage and selection operator regression analysis was used to reduce the feature dimension and construct an accurate radiomics signature based on the remaining texture features. Subsequently, we developed a model based on the radiomics signature and Alberta Stroke Program Early CT Score (ASPECTS) based on NCCT to predict mMCAi. Our prediction model showed a good predictive performance with an AUC of 0.917 [95% confidence interval (CI), 0.863-0.972] and 0.913 [95% CI, 0.795-1] in the training and validation sets, respectively. Additionally, the decision curve analysis (DCA) validated the clinical efficacy of the combined risk factors of radiomics signature and ASPECTS based on NCCT in the prediction of mMCAi development in patients with acute stroke across a wide range of threshold probabilities. Our research indicates that radiomics signature can be an instrumental tool to predict the risk of mMCAi.

7.
Front Oncol ; 10: 401, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32296639

RESUMO

Sialic acids (SA), negatively charged nine-carbon sugars, have long been implicated in cancer metastasis since 1960's but its detailed functional roles remain elusive. We present a computational analysis of transcriptomic data of cancer vs. control tissues of eight types in TCGA, aiming to elucidate the possible reason for the increased production and utilization of SAs in cancer and their possible driving roles in cancer migration. Our analyses have revealed for all cancer types: (1) the synthesis and deployment enzymes of SAs are persistently up-regulated throughout the progression for all but one cancer type; and (2) gangliosides, of which SAs are part, tend to converge to specific types that allow SAs to pack at high densities on cancer cell surface as a cancer advances. Statistical and modeling analyses suggest that (i) a highly plausible reason for the increased syntheses of SAs is to produce net protons, used for neutralizing the OH- persistently generated by elevated intracellular iron metabolism coupled with chronic inflammation in cancer tissues; (ii) the level of SA accumulation on cancer cell surface strongly correlates with the stage of cancer migration, as well as multiple migration-related characteristics such as altered cell-cell adhesion, mechanical stress, cell protrusion, and contraction; and (iii) the pattern of SA deployment correlates with the 5-year survival rate of a cancer type. Overall, our study provides strong evidence for that the continuous accumulation of SAs on cancer cell surface gives rise to increasingly stronger cell-cell repulsion due to their negative charges, leading to cell deformation by electrostatic force-induced mechanical compression, which is known to be able to drive cancer cell migration established by recent studies.

8.
Andrology ; 8(3): 793-806, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32012485

RESUMO

BACKGROUND: Diabetes mellitus (DM) induces impairment of male reproductive system and is considered as a key factor that could partially provide an explanation for male infertility. Thus, understanding the mechanism underlying DM-induced infertility will aid in the identification of novel therapeutic stratagems. OBJECTIVES: To delineate the role of ROS/JAK2/NFκB pathway in DM-induced low reproductive function and impaired spermatogenesis. Additionally, to investigate the protective effect of monomeric Berberine (BB) that inhibits ROS/JAK2/NFκB pathway, in the pathogenesis of DM-induced infertility. METHODS: 12-week-old male Sprague-Dawley rats were divided into four groups: control group, DM group, control plus BB group, and DM plus BB group. Streptozotocin was used to induce DM. After treating the rats with BB for 4 weeks, fertility tests were conducted to investigate the reproductive function, and testis weight along with sperm motility was assessed through microscope. Oxidative stress was evaluated by DHE staining. TUNEL staining was utilized to detect the state of apoptosis. Cell experiments were carried out to define the role of BB in vitro. Immunohistochemistry, immunofluorescence, and Western blotting were employed to measure the protein expression. RESULTS: Our results indicate that the reproductive function of DM rats was low, accompanied by decreased testis weight and sperm motility in addition to the impairment of the seminiferous tubules. However, there was a significant improvement in the reproductive function parameters in the BB-treated DM rats. Subsequently, our data revealed that DM rats produce an increased level of ROS in the testis, which activates JAK2 further activating the NFκB pathway, leading to increased apoptosis and impaired cells in the testicles. However, BB could attenuate the ROS production and abrogate activation of JAK2/NFκB pathway, thus inhibiting the apoptosis in the testicular cells of DM rats. CONCLUSION: ROS/JAK2/NFκB pathway is involved in the DM-induced low reproductive function and impaired spermatogenesis. BB can play a protective role in preserving the reproductive function and spermatogenesis in DM by inhibiting ROS/JAK2/NFκB pathway.

9.
Front Aging Neurosci ; 11: 323, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31824302

RESUMO

Background: Recent evidence suggests the presence of hippocampal neuroanatomical abnormalities in subjects of amnestic mild cognitive impairment (aMCI). Our study aimed to identify the radiomic biomarkers of the hippocampus for building the classification models in aMCI diagnosis. Methods: For this target, we recruited 42 subjects with aMCI and 44 normal controls (NC). The right and left hippocampi were segmented for each subject using an efficient learning-based method. Then, the radiomic analysis was applied to calculate and select the radiomic features. Finally, two logistic regression models were built based on the selected features obtained from the right and left hippocampi. Results: There were 385 features derived after calculation, and four features remained after feature selection from each group of data. The area under the receiver operating characteristic (ROC) curve, specificity, sensitivity, positive predictive value, negative predictive value, precision, recall, and F-score of the classification evaluation index of the right hippocampus logistic regression model were 0.76, 0.71, 0.69, 0.69, 0.71, 0.69, 0.69, and 0.69, and those of the left hippocampus model were 0.79, 0.71, 0.54, 0.64, 0.63, 0.64, 0.54, and 0.58, respectively. Conclusion: Results demonstrate the potential hippocampal radiomic biomarkers are valid for the aMCI diagnosis. The MRI-based radiomic analysis, with further improvement and validation, can be used to identify patients with aMCI and guide the individual treatment.

10.
J Sex Med ; 16(11): 1708-1720, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31564534

RESUMO

BACKGROUND: Oxidative stress is a significant contributor to the poor treatment efficacy on erectile dysfunction induced by diabetes mellitus (DMED). Thus, understanding the mechanism underlying oxidative stress will aid in the identification of novel therapeutic targets. AIM: To define the role of Janus kinase 2 (JAK2) in mediating oxidative stress in the corpus cavernosum smooth muscle cells (CCSMCs) and to investigate the therapeutic effect of monomeric berberine (BB), which inhibits JAK2, in the pathogenesis of DMED. METHODS: Streptozotocin was used to establish type I diabetic rat models and apomorphine tests were conducted to determine DMED rats. Eighteen DMED rats were divided into the DMED group and the DMED+BB group, whereas another 10 age-matched rats formed the control group. CCSMCs were isolated from the corpus cavernosum of rats and were treated with the JAK2 inhibitor alpha cyanano-(3,4-hydroxyl)N-benzophenylamine (AG490) and/or BB. OUTCOMES: Metabolic parameters; erectile function; histologic and molecular alterations. RESULTS: Erectile function was impaired and excessive oxidative stress was found in the DMED group. Excessive oxidative stress led to decreased expression level of phosphorylated endothelial nitric oxide synthase at serine 1177/endothelial nitric oxide synthase and increased expression level of Ras homolog gene family and Rho kinase 1/2. Meanwhile, the relative expression ratio of phosphorylated JAK2/JAK2 was significantly greater in the DMED group than that in the other groups. In vitro, oxidative stress was significantly reduced along with reduced intracellular calcium upon treatment with the JAK2 inhibitor, AG490. Moreover, the CCSMCs treated with BB showed changes similar to those upon treatment with AG490. In vivo experiments also confirmed that the erectile function of the DMED+BB group was improved, accompanied by decreased phosphorylated JAK2/JAK2 and decreased oxidative stress. CLINICAL TRANSLATION: JAK2 can be used as a therapeutic target and BB can be used as a potential drug for the clinical treatment of DMED. STRENGTHS AND LIMITATIONS: This study examines the promoting effect of JAK2 on oxidative stress occurrence in the corpus cavernosum and on the development of DMED in both animal experiments and cell experiments, as well evaluates the inhibitory effect of BB on JAK2 and its therapeutic effect on DMED. The main limitation of our current study is the lack of an appropriate means for activating JAK2. CONCLUSIONS: JAK2 can induce DMED by enhancing oxidative stress and BB can play a role in treating DMED by inhibiting JAK2 and reducing oxidative stress. Our study provides an option and an idea for further studies on the pathogenesis and treatment of DMED. Song J, Tang Z, Li H, et al. Role of JAK2 in the Pathogenesis of Diabetic Erectile Dysfunction and an Intervention With Berberine. J Sex Med 2019;16:1708-1720.


Assuntos
Berberina/farmacologia , Diabetes Mellitus Experimental/complicações , Disfunção Erétil/fisiopatologia , Janus Quinase 2/metabolismo , Animais , Masculino , Miócitos de Músculo Liso/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ereção Peniana/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Estreptozocina
11.
Front Neurosci ; 13: 435, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31133781

RESUMO

Alzheimer's disease (AD) is a neurodegenerative disease with main symptoms of chronic primary memory loss and cognitive impairment. The study aim was to investigate the correlation between intrahippocampal functional connectivity (FC) and MRI radiomic features in AD. A total of 67 AD patients and 44 normal controls (NCs) were enrolled in this study. Using the seed-based method of resting-state functional MRI (rs-fMRI), the whole-brain FC with bilateral hippocampus as seed was performed, and the FC values were extracted from the bilateral hippocampus. We observed that AD patients demonstrated disruptive FC in some brain regions in the left hippocampal functional network, including right gyrus rectus, right anterior cingulate and paracingulate gyri, bilateral precuneus, bilateral angular gyrus, and bilateral middle occipital gyrus. In addition, decreased FC was detected in some brain regions in the right hippocampal functional network, including bilateral anterior cingulate and paracingulate gyri, right dorsolateral superior frontal gyrus, and right precentral gyrus. Bilateral hippocampal radiomics features were calculated and selected using the A.K. software. Finally, Pearson's correlation analyses were conducted between these selected features and the bilateral hippocampal FC values. The results suggested that two gray level run-length matrix (RLM) radiomic features and one gray level co-occurrence matrix (GLCM) radiomic feature weakly associated with FC values in the left hippocampus. However, there were no significant correlations between radiomic features and FC values in the right hippocampus. These findings present that the AD group showed abnormalities in the bilateral hippocampal functional network. This is a prospective study that revealed the weak correlation between the MRI radiomic features and the intrahippocampal FC in AD patients.

12.
Cell Death Dis ; 10(4): 291, 2019 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-30926787

RESUMO

Macrophages play an important role in renal injury and repair after acute kidney injury (AKI) and the subsequent chronic kidney disease (CKD) that often results. However, as macrophages have a high degree of plasticity and heterogeneity, the function(s) of macrophage subtypes in AKI-to-CKD progression are not fully understood. Here, we focused on Ly6C- macrophages, which are derived from the embryonic yolk sac and post-development become resident in the kidneys. We found that C-C chemokine receptor type 2 (CCR2) deficiency, which blocks the migration of Ly6C+ macrophages from the bone marrow to the sites of injury, alleviated ischemia-induced AKI in mice. Unexpectedly, though, CCR2 deficiency worsened the subsequent renal fibrosis, which was marked by notable intra-renal infiltration of Ly6C- macrophages. These Ly6C- macrophages were greater in number in both the acute and chronic phases after ischemia reperfusion (I/R) in kidneys of wild type (WT) mice, and we showed them to be derived from the bone marrow by bone marrow chimerism. Clodronate Liposomes (CLs)-mediated depletion of renal Ly6C- macrophages in CCR2-/- mice or in WT mice after I/R alleviated the renal injury and fibrosis. On the contrary, adoptive transfer of Ly6C- macrophages from injured kidneys of WT mice into immune-deficient mice was sufficient to induce renal injury and fibrosis. Transcriptome sequencing of Ly6C- macrophages from injured kidneys revealed that they secreted various cytokines and growth factors, which were associated with the transdifferentiation of fibroblasts into myofibroblasts. This transdifferentiation effect was further supported by in vitro studies showing that Ly6C- macrophages induced the secretion of extracellular matrix proteins from co-cultured fibroblasts. In conclusion, the presence of bone marrow-derived Ly6C- macrophages after ischemia induces AKI and worsens subsequent CKD.


Assuntos
Lesão Renal Aguda/etiologia , Lesão Renal Aguda/metabolismo , Antígenos Ly/metabolismo , Isquemia/complicações , Macrófagos/metabolismo , Insuficiência Renal Crônica/etiologia , Insuficiência Renal Crônica/metabolismo , Transferência Adotiva , Animais , Movimento Celular/genética , Transdiferenciação Celular , Citocinas/genética , Proteínas da Matriz Extracelular/metabolismo , Fibroblastos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Camundongos Knockout , Miofibroblastos/metabolismo , Receptores CCR2/deficiência , Receptores CCR2/genética , Traumatismo por Reperfusão/metabolismo , Transcriptoma
13.
Asian J Androl ; 21(4): 413-418, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30604694

RESUMO

Gonadotropin therapy is commonly used to induce virilization and spermatogenesis in male isolated hypogonadotropic hypogonadism (IHH) patients. In clinical practice, 5.6%-15.0% of male IHH patients show poor responses to gonadotropin treatment; therefore, testosterone (T) supplementation can serve as an alternative therapy to normalize serum T levels and promote virilization. However, treatment with exogenous T impairs spermatogenesis and suppresses intratesticular T levels. This retrospective study aimed to determine whether oral testosterone undecanoate (TU) supplementation together with human chorionic gonadotropin (hCG) would negatively affect spermatogenesis in IHH patients compared with hCG alone. One hundred and seven IHH patients were included in our study. Fifty-four patients received intramuscular hCG and oral TU, and 53 patients received intramuscular hCG alone. The median follow-up time was 29 (range: 12-72) months in both groups. Compared with the hCG group, the hCG/TU group required a shorter median time to normalize serum T levels (P < 0.001) and achieve Tanner stage (III and V) of pubic hair and genital development (P < 0.05). However, there were no significant differences in the rate of seminal spermatozoa appearance, sperm concentration, or median time to achieve different sperm concentration thresholds between the groups. In addition, there were no significant differences in side effects, such as acne and gynecomastia, observed in both groups. This study indicates that oral TU supplementation together with hCG does not impair spermatogenesis in treated IHH patients compared with hCG alone, and it shortens the time to normalize serum T levels and promote virilization.


Assuntos
Gonadotropina Coriônica/farmacologia , Hipogonadismo/tratamento farmacológico , Espermatogênese/efeitos dos fármacos , Testosterona/análogos & derivados , Adolescente , Adulto , Gonadotropina Coriônica/uso terapêutico , Quimioterapia Combinada , Hormônio Foliculoestimulante/sangue , Humanos , Hipogonadismo/sangue , Hormônio Luteinizante/sangue , Masculino , Estudos Retrospectivos , Testosterona/sangue , Testosterona/farmacologia , Testosterona/uso terapêutico , Resultado do Tratamento , Adulto Jovem
14.
Annu Int Conf IEEE Eng Med Biol Soc ; 2019: 2045-2048, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31946303

RESUMO

Diabetic retinopathy (DR) is one kind of eye disease that is caused by overtime diabetes. Lots of patients around the world suffered from DR which may bring about blindness. Early detection of DR is a rigid quest which can remind the DR patients to seek corresponding treatments in time. This paper presents an automatic image-level DR detection system using multiple well-trained deep learning models. Besides, several deep learning models are integrated using the Adaboost algorithm in order to reduce the bias of each single model. To explain the results of DR detection, this paper provides weighted class activation maps (CAMs) that can illustrate the suspected position of lesions. In the pre-processing stage, eight image transformation ways are also introduced to help augment the diversity of fundus images. Experiments demonstrate that the method proposed by this paper has stronger robustness and acquires more excellent performance than that of individual deep learning model.


Assuntos
Aprendizado Profundo , Diabetes Mellitus , Retinopatia Diabética/classificação , Algoritmos , Fundo de Olho , Humanos
15.
Annu Int Conf IEEE Eng Med Biol Soc ; 2019: 6255-6258, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31947272

RESUMO

The main purpose of this paper is to quantificationally predict the pathologic characteristics of pulmonary nodules using a novel and effective computer assisted diagnosis (CADx) scheme based on latent Dirichlet allocation (LDA) model. To make use of LDA model, we propose a novel 3D rotation invariant LBP feature to construct image words through the K-means algorithm from 3D pulmonary nodule slices. A topic distribution for each pulmonary nodule can be acquired by well-trained LDA model, which was used for pathologic analysis based on rank-based statistical analysis. Using the LIDC/IDRI database, this study made experiments based on different parameters, including topic number and size of vocabulary. Experiments demonstrate that the performance of all the characteristics reached to accuracies of more than 80%. Especially, this study obtained an accuracy of 84.2% with the root mean square error (RMSE) of 1.068 on quantitative assessment of malignancy likelihood. Compared with the latest study of multi-task convolutional neutral network regression, the proposed method can obtain more accurate results of characteristic prediction of a pulmonary nodule.


Assuntos
Neoplasias Pulmonares/diagnóstico por imagem , Interpretação de Imagem Radiográfica Assistida por Computador , Nódulo Pulmonar Solitário/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Algoritmos , Humanos , Imageamento Tridimensional , Neoplasias Pulmonares/patologia , Nódulo Pulmonar Solitário/patologia
16.
Oxid Med Cell Longev ; 2018: 1724648, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30405874

RESUMO

Solute carrier family 26 member 6 (Slc26a6), which is mainly expressed in the intestines and kidneys, is a multifunctional anion transporter that is crucial in the transport of oxalate anions. This study is aimed at investigating the effect of Slc26a6 expression on oxalate-induced cell oxidation and crystal formation. Lentivirus transfection was used to upregulate or downregulate Slc26a6 expression in NRK cells. Cell viability and apoptosis, reactive oxygen species (ROS) and malondialdehyde (MDA) generation, and superoxide dismutase (SOD) activity were measured. Crystal adhesion and the cell ultrastructure were observed using light and transmission electron microscopy (TEM). Three groups of rats, normal control, lentivirus-vector, and lentivirus-small interfering RNA (lv-siRNA) groups, were used, and after lentivirus transfection, they were fed 1% ethylene glycol (EG) and 0.5% ammonium chloride (NH4Cl) for 2 weeks. Dihydroethidium (DHE), terminal deoxynucleotidyl transferase (TdT) deoxyuridine dUTP nick-end labeling (TUNEL), and von Kossa staining were performed, and nuclear factor κB (NFκB) and osteopontin (OPN) expression were measured. In the vitro study, compared to the control group, downregulated Slc26a6 NRK cells showed alleviation of the cell viability decrease, cell apoptosis rate, ROS generation, and SOD activity decrease after oxalate treatment. Crystal adhesion and vesicles were significantly less after oxalate exposure than in the untreated controls. Rats infected with lentivirus-siRNA exhibited attenuated SOD generation, cell apoptosis, and crystal formation in the kidneys. Increased phosphorylation of NFκB and OPN was involved in the pathological process. In conclusion, the results of the present study indicate that reducing the expression of Slc26a6 in the kidney may be a potential strategy for preventing stone formation.


Assuntos
Antiporters/metabolismo , Regulação para Baixo , Espaço Intracelular/metabolismo , Estresse Oxidativo , Animais , Apoptose , Linhagem Celular , Sobrevivência Celular , Vesículas Citoplasmáticas/metabolismo , Vesículas Citoplasmáticas/ultraestrutura , Rim/patologia , Peroxidação de Lipídeos , Masculino , Modelos Biológicos , Inibidor de NF-kappaB alfa/metabolismo , Osteopontina/metabolismo , Oxalatos , RNA Interferente Pequeno/metabolismo , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Transportadores de Sulfato , Fator de Transcrição RelA/metabolismo , Transfecção , Transgenes
17.
Front Neurol ; 9: 618, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30093881

RESUMO

Background: Alzheimer's disease (AD) is a progressive neurodegenerative disease that causes the decline of some cognitive impairments. The present study aimed to identify the corpus callosum (CC) radiomic features related to the diagnosis of AD and build and evaluate a classification model. Methods: Radiomics analysis was applied to the three-dimensional T1-weighted magnetization-prepared rapid gradient echo (MPRAGE) images of 78 patients with AD and 44 healthy controls (HC). The CC, in each subject, was segmented manually and 385 features were obtained after calculation. Then, the feature selection were carried out. The logistic regression model was constructed and evaluated according to identified features. Thus, the model can be used for distinguishing the AD from HC subjects. Results: Eleven features were selected from the three-dimensional T1-weighted MPRAGE images using the LASSO model, following which, the logistic regression model was constructed. The area under the receiver operating characteristic curve values (AUC), sensitivity, specificity, accuracy, precision, and positive and negative predictive values were 0.720, 0.792, 0.500, 0.684, 0.731, 0.731, and 0.583, respectively. Conclusion: The results demonstrated the potential of CC texture features as a biomarker for the diagnosis of AD. This is the first study showing that the radiomics model based on machine learning was a valuable method for the diagnosis of AD.

18.
PeerJ ; 6: e5192, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30002986

RESUMO

Background: Solute-linked carrier 26 gene family 6 (SLC26A6), which is mainly expressed in intestines and kidneys, is a multifunctional anion transporter crucial in the transport of oxalate anions. This study aimed to investigate the role of kidney SLC26A6 in urolithiasis. Methods: Patients were divided into two groups: stone formers and nonstone formers. Samples were collected from patients following nephrectomy. Lentivirus with Slc26a6 (lentivirus-Slc26a6) sequence and lentivirus with siRNA-Slc26a6 (lentivirus-siRNA-Slc26a6) sequence were transfected into rats' kidneys respectively and Slc26a6 expression was detected using Western blot and immunohistochemical analyses. After administering ethylene glycol, oxalate concentration and prevalence of stone formation between the transgenic and control groups were measured using 24-h urine analysis and Von Kossa staining, respectively. Results: Immunohistochemical and Western blot analyses indicated that stone formers had a significantly higher level of expression of SLC26A6 in the kidney compared with the control group. After lentivirus infection, the urinary oxalate concentration and rate of stone formation in lentivirus-Slc26a6-tranfected rats increased remarkably, while lentivirus-siRNA-Slc26a6-transfected rats showed few crystals. Conclusion: The results showed that high expression levels of renal SLC26A6 may account for kidney stone formation. Downregulating the expression of SLC26A6 in the kidney may be a potential therapeutic target to prevent or treat urolithiasis.

19.
J Assist Reprod Genet ; 35(7): 1247-1257, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29785532

RESUMO

PURPOSE: The purpose of the study is to explore testicular sperm cryopreservation in patients with nonobstructive azoospermia (NOA) whether affect the outcome of subsequent intracytoplasmic sperm injection (ICSI). METHODS: A systematic review and meta-analysis was conducted by searching the MEDLINE and EMBASE databases for relevant published studies in English language (1997-2017). Studies were eligible if they included the comparison of using fresh and frozen-thawed testicular sperm followed by ICSI. Two reviewers independently performed data extraction, quality assessment and assessed the risk of bias. The overall summary risk estimated the number of events. A meta-analysis was conducted using a random effects or fixed effects model analysis according to the test of heterogeneity. RESULTS: A total of 17 studies with 1,261 ICSI cycles were identified. Analysis of the present data showed no difference in the fertilization outcome when comparing fresh versus frozen-thawed spermatozoa (RR = 1.02, 95% CI 0.86-1.09). Similarly, no difference in CR (RR = 1.01, 95% CI 0.96-1.05), good embryo rate (RR = 1.01, 95% CI 0.95-1.09), and IR (RR = 0.93, 95% CI 0.66-1.30) was observed if the spermatozoa was fresh or frozen-thawed. Finally, no difference in CPR or LBR was noted when using fresh or frozen-thawed cycles were analyzed separately (RR = 1.03, 95% CI 0.86-1.24; RR 1.11, 95% CI 0.88-1.41, respectively). CONCLUSIONS: In men with NOA, the ICSI outcome is not affected by whether the retrieved testicular sperm is fresh or frozen. Sperm cryopreservation ought to be considered in every surgical sperm retrieval case, which remain feasible even in patients with few testicular sperm retrieved.


Assuntos
Azoospermia/fisiopatologia , Espermatozoides/fisiologia , Testículo/fisiologia , Criopreservação/métodos , Transferência Embrionária/métodos , Feminino , Humanos , Masculino , Gravidez , Resultado da Gravidez , Taxa de Gravidez , Preservação do Sêmen/métodos , Recuperação Espermática
20.
IEEE J Biomed Health Inform ; 22(4): 1227-1237, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-28715341

RESUMO

High-efficiency lung nodule detection dramatically contributes to the risk assessment of lung cancer. It is a significant and challenging task to quickly locate the exact positions of lung nodules. Extensive work has been done by researchers around this domain for approximately two decades. However, previous computer-aided detection (CADe) schemes are mostly intricate and time-consuming since they may require more image processing modules, such as the computed tomography image transformation, the lung nodule segmentation, and the feature extraction, to construct a whole CADe system. It is difficult for these schemes to process and analyze enormous data when the medical images continue to increase. Besides, some state of the art deep learning schemes may be strict in the standard of database. This study proposes an effective lung nodule detection scheme based on multigroup patches cut out from the lung images, which are enhanced by the Frangi filter. Through combining two groups of images, a four-channel convolution neural networks model is designed to learn the knowledge of radiologists for detecting nodules of four levels. This CADe scheme can acquire the sensitivity of 80.06% with 4.7 false positives per scan and the sensitivity of 94% with 15.1 false positives per scan. The results demonstrate that the multigroup patch-based learning system is efficient to improve the performance of lung nodule detection and greatly reduce the false positives under a huge amount of image data.


Assuntos
Aprendizado Profundo , Neoplasias Pulmonares/diagnóstico por imagem , Pulmão/diagnóstico por imagem , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Algoritmos , Humanos , Tomografia Computadorizada por Raios X
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