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1.
Medicine (Baltimore) ; 99(11): e19268, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32176050

RESUMO

The purpose of this study was to investigate metal artifact reduction effect of orthopedics metal artifact reduction (O-Mar) algorithm in computer tomography (CT) image of patients who have undergone total hip arthroplasty (THA) or total knee arthroplasty (TKA).35 cases of patients who underwent TKA or THA have been recruited in this study. CT image of hip or knee joint was obtained with Philips 256-row CT scanner. Tube voltages of 120 and 140 kilovolt peak (KVP) were set. Afterwards, CT image was reconstructed by O-Mar algorithm to reduce metal artifact. Grade of image quality and severity of metal artifact would be taken into qualitative evaluation. While, quantitative evaluation mainly included measurement of metal artifact volume and 2D measurement of average CT value in region of interest (ROI). The visibility of interface between bone-prostheses was also estimated.Result of qualitative analysis indicated that score of CT quality was improved and grade of metal artifact was decreased significantly with O-Mar. Quantitative analysis illustrated that volume of beam-hardening (B-H) metal artifact decreased remarkably after reconstruction of O-Mar (P < .001). In addition, O-Mar algorithm reduced 83.3% to 83.7% volume of photon-starvation (P-S) metal artifact. As for result of 2D measurement, CT value in ROI was closer to standard value in O-Mar group CT image (P < .001). Meanwhile, error of CT value also decreased significantly after reconstruction of O-Mar algorithm. Visibility rate of bone-prosthesis interface improved from 34.3% (Non-O-Mar) to 66.7% (O-Mar).O-Mar algorithm could significantly reduce metal artifact in CT image of THA and TKA in both 2D and three-dimensional (3D) level. Therefore, better image quality and visibility of bone-prostheses interface could be presented. In this study, O-Mar was proved as an efficient metal artifact reduction method in CT image of THA and TKA.


Assuntos
Algoritmos , Artroplastia de Quadril/métodos , Artroplastia do Joelho/métodos , Artefatos , Intensificação de Imagem Radiográfica/métodos , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Estudos de Coortes , Feminino , Humanos , Prótese do Joelho , Masculino , Metais , Pessoa de Meia-Idade , Ortopedia , Estudos Retrospectivos
2.
Ultrasound Med Biol ; 2020 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-32151412

RESUMO

The aims of the study described here were to evaluate medial arterial calcification (MAC) of the lower limbs, identified on ultrasound, in patients with type 2 diabetes, and to analyze the association of MAC with diabetic complications including peripheral arterial disease, peripheral neuropathy, retinopathy, and nephropathy. Ultrasound was performed in 359 patients, and the severity of MAC was assessed by the length of MAC (score range: 0-8) and the number of arterial segmentations with MAC (score range: 0-6). Our results revealed that MAC scoring based on the segmentation method was an independent predictor of peripheral arterial disease and nephropathy, but not an independent predictor of peripheral neuropathy or retinopathy. MAC scoring based on the length method was not an independent predictor of any complication. The segmentation method for assessing MAC on ultrasound may be a valuable tool in clinical work.

3.
Brain Behav Immun ; 2020 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-32169498

RESUMO

Since December 2019, more than 79,000 people have been diagnosed with infection of the Corona Virus Disease 2019 (COVID-19). A large number of medical staff was sent to Wuhan city and Hubei province to aid COVID-19 control. Psychological stress, especially vicarious traumatization caused by the COVID-19 pandemic, should not be ignored. To address this concern, the study employed a total of 214 general public and 526 nurses (i.e., 234 front-line nurses and 292 non-front-line nurses) to evaluate vicarious traumatization scores via a mobile app-based questionnaire. Front-line nurses are engaged in the process of providing care for patients with COVID-19. The results showed that the vicarious traumatization scores for front-line nurses including scores for physiological and psychological responses, were significantly lower than those of non-front-line nurses (P < 0.001). Interestingly, the vicarious traumatization scores of the general public were significantly higher than those of the front-line nurses (P < 0.001); however, no statistical difference was observed compared to the scores of non-front-line nurses (P > 0.05). Therefore, increased attention should be paid to the psychological problems of the medical staff, especially non-front-line nurses, and general public under the situation of the spread and control of COVID-19. Early strategies that aim to prevent and treat vicarious traumatization in medical staff and general public are extremely necessary.

4.
Bioengineered ; 11(1): 189-200, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32050841

RESUMO

MicroRNAs (miRNAs) have emerged as critical regulators of neuronal survival during cerebral ischemia/reperfusion injury. Accumulating evidence has shown that miR-211 plays a crucial role in regulating apoptosis and survival in various cell types. However, whether miR-211 is involved in regulating neuronal survival during cerebral ischemia/reperfusion injury remains unknown. In this study, we aimed to explore the biological role of miR-211 in regulating neuronal injury induced by oxygen-glucose deprivation/reoxygenation (OGD/R) and transient cerebral ischemia/reperfusion (I/R) injury in vitro and in vivo. We found that miR-211 expression was significantly downregulated in PC12 cells in response to OGD/R and in the penumbra of mouse in response to MCAO. Overexpression of miR-211 alleviated OGD/R-induced PC12 cell apoptosis, whereas miR-211 inhibition facilitated OGD/R-induced PC12 cell apoptosis in vitro. Moreover, overexpression of miR-211 reduced infarct volumes, neurologic score, and neuronal apoptosis in vivo, whereas miR-211 inhibition increased infarct volumes, neurologic score and neuronal apoptosis in vivo. Notably, our results identified P53-up-regulated modulator of apoptosis (PUMA) as a target gene of miR-211. Our findings suggested that miR-211 may protect against MCAO injury by targeting PUMA in rats, which paves a potential new way for the therapy of cerebral I/R injury.

5.
Artigo em Inglês | MEDLINE | ID: mdl-32109138

RESUMO

Background: Zhang et al. characterized a novel oncogenic long noncoding RNA (lncRNA) named NR2F2-AS1 in lung cancer. In this study, the role of lncRNA NR2F2-AS1 in clear cell renal cell carcinoma (ccRCC) was explored. Materials and Methods: Levels of NR2F2-AS1 and Rac1 mRNA expression in both cancer and noncancer tissues from 60 patients with ccRCC were measured by performing RT-qPCR. NR2F2-AS1 siRNA silencing and overexpression experiments were performed to analyze the role of NR2F2-AS1 in regulating Rac1 expression. Cell stemness was analyzed by stemness assay. Results: NR2F2-AS1 was upregulated in ccRCC, and high NR2F2-AS1 expression levels in ccRCC tissues were associated with poor survival. Rac1 was also upregulated in ccRCC and positively correlated with NR2F2-AS1. In ccRCC cells, NR2F2-AS1 overexpression mediated the upregulation of Rac1, whereas NR2F2-AS1 siRNA was accompanied by Rac1 downregulation. NR2F2-AS1 and Rac1 overexpression resulted in the increased ccRCC cell stemness, whereas NR2F2-AS1 and Rac1 siRNA silencing played an opposite role. Rac1 overexpression inhibited the role of NR2F2-AS1 siRNA silencing. Conclusions: NR2F2-AS1 may upregulate Rac1 to increase cancer stemness in ccRCC.

6.
J Neurol ; 2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-32006159

RESUMO

OBJECTIVE: This meta-analysis aimed to systematically evaluate the effectiveness and safety of galcanezumab in the prophylactic treatment of adult migraine. METHODS: A systematic literature search was performed to identity randomized-controlled trials (RCTs). The primary outcome was the decline in the number of monthly migraine days (MMDs). Secondary outcomes included the reduction of monthly acute migraine­specific medication days (MSMDs), the number of participants showing a reduction in MMDs from baseline of ≥ 50%, ≥ 75%, and 100%, the incidence of adverse events (AEs), and the number of participants developing anti-drug antibodies (ADAs) to galcanezumab. We calculated the mean difference (MD), relative risk (RR), and 95% confidence intervals (CIs) for these outcomes. RESULTS: Among the five included trials, galcanezumab given at doses of 120, 150, 240, and 300 mg was superior to placebo for both MMDs and secondary outcomes. The degree of AEs in all group was mild. Notably, no significant differences were found in the occurrence of AEs and ADAs between the galcanezumab and placebo groups. CONCLUSION: Galcanezumab is a safe and effective treatment for adult patients with episodic and chronic migraine.

7.
Calcif Tissue Int ; 106(4): 355-363, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31932859

RESUMO

Microvascular complications are prevalent in patients with type 2 diabetes mellitus (T2DM), resulting in increased risk of cardiovascular mortality. However, it is unclear whether above-knee artery calcification relates to microvascular complications. This study was aimed to investigate the role of calcification in superficial femoral arteries (SFA), the major above-knee artery, compared with anterior tibial arteries (ATA) and posterior tibial arteries (PTA), in T2DM-related microvascular complications and explore its risk factors. A single-center and observational study involving 359 T2DM patients was conducted. Clinical and laboratory data were collected. SFA calcification was evaluated by ultrasonography. Compared with ATA and PTA calcification, operating characteristics curve analysis showed that SFA calcification was the strongest predictor (63.1% sensitivity and 69.2% specificity) for T2DM-related microvascular complications (diabetic neuropathy, diabetic nephropathy and diabetic retinopathy). With the severity of SFA calcification increased, age, duration of T2DM, and SBP were significantly elevated, but triglyceride and glucose index and estimated glomerular filtration rate (eGFR) were significantly reduced (all P < 0.05). Multivariate logistic analysis showed that eGFR (OR 0.953; 95% CI 0.931-0.976; P < 0.001) was an independent risk factor of SFA calcification, especially in young patients with HbA1c > 7.0. We identified SFA calcification as a good predictor of microvascular complications in T2DM patients. Reduced eGFR was significantly associated with increased SFA calcification prevalence, especially in young T2DM patients with bad controlled hyperglycemia.

8.
Neuroradiology ; 62(3): 347-352, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31912185

RESUMO

PURPOSE: Retinal pigment epithelium (RPE) adenoma is a rare intraocular benign tumor. It is almost always misdiagnosed as uveal melanoma (UM) resulting in inappropriate management. The purpose of this study was to investigate MRI features of the RPE adenoma that may help differentiate this entity from UM. METHODS: MRI was performed in eight patients with pathology-proven RPE adenoma, five of whom had dynamic contrast-enhanced (DCE) MRI. The time-intensity curves (TIC) of all DCE-MRI were evaluated, and the maximum contrast index (CImax) were calculated. RESULTS: All eight tumors showed well-defined margins. They were homogeneously hyperintense on T1WI and hypointense on T2WI compared to vitreous body. An oval mass was seen in five tumors, lentiform in two tumors, and placoid-shaped in one tumor. After contrast administration, mild enhancement was identified in five tumors and moderate enhancement in three tumors. In all five tumors, DCE-MRI exhibited a plateau-shaped TIC with a median CImax of 0.37. A "dark-linear sign" (defined as low signal intensity linear zone located between tumor and enhanced choroid on post contrast T1WI with fat-suppression) was noted in all eight patients with RPE adenoma. CONCLUSION: RPE adenoma and UM often have similar MR imaging findings. This study reports for the first time a "dark-linear sign" on post contrast T1WI with fat-suppression seen in RPE adenoma. This observation may be characteristic of RPE adenoma and may help separate this entity from UM.

9.
Mol Pharm ; 17(3): 817-826, 2020 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-31910019

RESUMO

Biomedical nanoplatforms have been widely investigated for ultrasound (US) imaging and cancer therapy. Herein, perfluorocarbon (PFC) is encapsulated into biocompatible polydopamine (PDA) to form a theranostic nanosystem, followed by the modification of polyethylene glycol (PEG) to stabilize the nanoparticle via a facile one-pot method. Under 808 nm near-infrared laser irradiation, PDA can generate hyperthermia to transform PFC droplets to bubbles with high US imaging sensitivity. The US imaging detection of the PFC-PDA-PEG nanosystem is achievable in a time span of up to 25 min in vitro at a low US frequency and mechanical index, manifesting a US imaging performance for in vivo application. Moreover, tumor cells incubated with the nanosystem are ablated effectively under laser irradiation at 808 nm. The results illustrate the potential of the PDA-based theranostic agent in US imaging-guided photothermal therapy of tumor.

10.
J Diabetes Res ; 2020: 2969105, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31998805

RESUMO

Background: Sleep duration is associated with type 2 diabetes (T2D). However, few T2D risk scores include sleep duration. We aimed to develop T2D scores containing sleep duration and to estimate the additive value of sleep duration. Methods: We used data from 43,404 adults without T2D in the Beijing Health Management Cohort study. The participants were surveyed approximately every 2 years from 2007/2008 to 2014/2015. Sleep duration was calculated from the self-reported usual time of going to bed and waking up at baseline. Logistic regression was employed to construct the risk scores. Integrated discrimination improvement (IDI) and net reclassification improvement (NRI) were used to estimate the additional value of sleep duration. Results: After a median follow-up of 6.8 years, we recorded 2623 (6.04%) new cases of T2D. Shorter (both 6-8 h/night and <6 h/night) sleep durations were associated with an increased risk of T2D (odds ratio (OR) = 1.43, 95% confidence interval (CI) = 1.30-1.59; OR = 1.98, 95%CI = 1.63-2.41, respectively) compared with a sleep duration of >8 h/night in the adjusted model. Seven variables, including age, education, waist-hip ratio, body mass index, parental history of diabetes, fasting plasma glucose, and sleep duration, were selected to form the comprehensive score; the C-index was 0.74 (95% CI: 0.71-0.76) for the test set. The IDI and NRI values for sleep duration were 0.017 (95% CI: 0.012-0.022) and 0.619 (95% CI: 0.518-0.695), respectively, suggesting good improvement in the predictive ability of the comprehensive nomogram. The decision curves showed that women and individuals older than 50 had more net benefit. Conclusions: The performance of T2D risk scores developed in the study could be improved by containing the shorter estimated sleep duration, particularly in women and individuals older than 50.

11.
Hum Reprod ; 35(1): 203-211, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31955198

RESUMO

STUDY QUESTION: Is age at natural menopause (ANM) associated with the development of multiple chronic conditions (multimorbidity) in postmenopausal life? SUMMARY ANSWER: Women with premature menopause experience increased odds of developing individual chronic conditions and multimorbidity. WHAT IS KNOWN ALREADY: ANM is considered as a marker of age-related morbidity and mortality in postmenopausal life. Multimorbidity affects more than 60% of older women and has been recognized as the most common 'chronic condition'. Few studies have examined the association between ANM and the development of multimorbidity. STUDY DESIGN, SIZE, DURATION: A prospective national cohort study of 11 258 Australian women, aged 45-50 years in 1996. Women were followed from 1996 to 2016. PARTICIPANTS/MATERIALS, SETTING, METHODS: Information about ANM and 11 chronic conditions (diabetes, hypertension, heart disease, stroke, arthritis, osteoporosis, asthma, chronic obstructive pulmonary disease, depression, anxiety and breast cancer) were estimated approximately every 3 years. Multimorbidity is defined as 2 or more of these 11 conditions. Generalized estimating equations were used to link the categorical ANM with individual chronic conditions and multimorbidity. MAIN RESULTS AND THE ROLE OF CHANCE: Among 5107 women reporting ANM, 2.3% experienced premature menopause (≤40 years) and 55.1% developed multimorbidity. Compared with women who experienced menopause at age 50-51 years, women with premature menopause had twice the odds of experiencing multimorbidity by age 60 (OR = 1.98, 95% CI 1.31 to 2.98) and three times the odds of developing multimorbidity in their 60s (OR = 3.03, 95% CI 1.62 to 5.64). Women with premature menopause also experienced higher incidence of most individual chronic conditions. LIMITATIONS, REASONS FOR CAUTION: The main limitation of this study was the use of self-reported data, but with repeated assessments from prospective study design and the validity of most of the chronic conditions from hospital data, the potential for non-differential misclassification is minimized. WIDE IMPLICATIONS OF THE FINDINGS: To our knowledge, this is the first study to assess the association of premature menopause and development of multimorbidity in a larger national cohort of mid-aged women. Health professionals should consider comprehensive screening and assessment of risk factors for multimorbidity when treating women who experienced premature menopause. STUDY FUNDING/COMPETING INTEREST(S): The Australian Longitudinal Study on Women's Health was supported by the Australian Government Department of Health. X.X. is funded by an International Postgraduate Research Scholarship from the Australian government and a UQ Centennial Scholarship from The University of Queensland. G.D.M. is supported by the National Health and Medical Research Council Principal Research Fellowship (APP1121844). None of the authors has any conflicts of interest to declare.

12.
IEEE Trans Cybern ; 50(2): 821-834, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30346301

RESUMO

Learning domain adaptive features aims to enhance the classification performance of the target domain by exploring the discriminant information from an auxiliary source set. Let X denote the feature and Y as the label. The most typical problem to be addressed is that P XY has a so large variation between different domains that classification in the target domain is difficult. In this paper, we study the generalized conditional domain adaptation (DA) problem, in which both P Y and P X|Y change across domains, in a causal perspective. We propose transforming the class conditional probability matching to the marginal probability matching problem, under a proper assumption. We build an intermediate domain by employing a regression model. In order to enforce the most relevant data to reconstruct the intermediate representations, a low-rank constraint is placed on the regression model for regularization. The low-rank constraint underlines a global algebraic structure between different domains, and stresses the group compactness in representing the samples. The new model is considered under the discriminant subspace framework, which is favorable in simultaneously extracting the classification information from the source domain and adaptation information across domains. The model can be solved by an alternative optimization manner of quadratic programming and the alternative Lagrange multiplier method. To the best of our knowledge, this paper is the first to exploit low-rank representation, from the source domain to the intermediate domain, to learn the domain adaptive features. Comprehensive experimental results validate that the proposed method provides better classification accuracies with DA, compared with well-established baselines.

13.
14.
BMC Health Serv Res ; 19(1): 966, 2019 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-31842861

RESUMO

BACKGROUND: Although public medical insurance covers over 95% of the population in China, disparities in health service use and out-of-pocket (OOP) health expenditure across income groups are still widely observed. This study aims to investigate the socio-economic disparities in perceived healthcare needs, informal care, formal care and payment for healthcare and explore their equity implication. METHODS: We assessed healthcare needs, service use and payment in 400 households in rural and urban areas in Jiangsu, China, and included only the adult sample (N = 925). One baseline survey and 10 follow-up surveys were conducted during the 7-month monitoring period, and the Affordability Ladder Program (ALP) framework was adopted for data analysis. Negative binomial/zero-inflated negative binomial and logit regression models were used to explore factors associated with perceived needs of care and with the use of self-treatment, outpatient and inpatient care respectively. Two-part model and logit regression modeling were conducted to explore factors associated with OOP health expenditure and with the likelihood of incurring catastrophic health expenditure (CHE). RESULTS: After adjusting for covariates, rural residence was significantly associated with more perceived healthcare needs, more self-treatment, higher probability of using outpatient and inpatient service, more OOP health expenditure and higher likelihood of incurring catastrophic expenditure (P < 0.05). Compared to the Urban Employee Basic Medical Insurance (UEBMI), enrollment in the New Rural Cooperative Medical Scheme (NRCMS) or in the Urban Resident Basic Medical Insurance (URBMI) was correlated with lower probability of ever using outpatient services, but with more outpatient visits when people were at risk of using outpatient service (P < 0.05). NRCMS/URBMI enrollment was also associated with higher likelihood of incurring CHE compared to UEBMI enrollment (OR = 2.02, P < 0.05); in stratified analysis of the rural and urban sample this effect was only significant for the rural population. CONCLUSIONS: The rural population in Jiangsu perceived more healthcare needs, had a higher probability of using both informal and formal healthcare services, and had more OOP health expenditure and a higher likelihood of incurring CHE. The inequity mainly exists in health care financing, and may be partially addressed through improving the benefit packages of NRCMS/URBMI.


Assuntos
Custos de Cuidados de Saúde/estatística & dados numéricos , Gastos em Saúde/estatística & dados numéricos , Necessidades e Demandas de Serviços de Saúde , Disparidades em Assistência à Saúde/estatística & dados numéricos , Programas Nacionais de Saúde/economia , Adulto , Idoso , Assistência Ambulatorial/economia , China , Feminino , Disparidades em Assistência à Saúde/economia , Humanos , Seguro Saúde/economia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , População Rural , População Urbana
15.
Artigo em Inglês | MEDLINE | ID: mdl-31683470

RESUMO

OBJECTIVE: To evaluate the combined use of strain elastography (SE) and superb microvascular imaging (SMI) with grayscale ultrasound (US) according to the Breast Imaging Reporting and Data System (BI-RADS) classification for differentiating benign from malignant breast masses. METHODS: In total, 166 patients with 177 breast masses categorized as BI-RADS 3-5 were included in the study between April 2016 to September 2017. US, SMI and SE were performed to evaluate each mass. The following outcome measures were compared between US and the combinations of US, SMI, and SE: area under the receiver operating characteristic curve (AUC), sensitivity, specificity. RESULTS: The addition of SMI and SE to US increased the AUC from 0.816 to 0.948 (P < .001); and the specificity from 43.7% to 80.8% (P < .001), without a significant decrease in the sensitivity. Meanwhile, 66.1% (37 of 56) of the benign masses that were indicated for unnecessary biopsy were correctly changed to follow-up. CONCLUSIONS: The addition SMI and SE to US could improve the diagnostic performance in differentiating benign from malignant breast masses compared to US alone. When US was combined with SMI and SE, the specificity were increased, thus significantly reducing unnecessary biopsies.

16.
Artigo em Inglês | MEDLINE | ID: mdl-31765312

RESUMO

Image set recognition has been widely applied in many practical problems like real-time video retrieval and image caption tasks. Due to its superior performance, it has grown into a significant topic in recent years. However, images with complicated variations, e.g., postures and human ages, are difficult to address, as these variations are continuous and gradual with respect to image appearance. Consequently, the crucial point of image set recognition is to mine the intrinsic connection or structural information from the image batches with variations. In this work, a Discriminant Residual Analysis (DRA) method is proposed to improve the classification performance by discovering discriminant features in related and unrelated groups. Specifically, DRA attempts to obtain a powerful projection which casts the residual representations into a discriminant subspace. Such a projection subspace is expected to magnify the useful information of the input space as much as possible, then the relation between the training set and the test set described by the given metric or distance will be more precise in the discriminant subspace. We also propose a nonfeasance strategy by defining another approach to construct the unrelated groups, which help to reduce furthermore the cost of sampling errors. Two regularization approaches are used to deal with the probable small sample size problem. Extensive experiments are conducted on benchmark databases, and the results show superiority and efficiency of the new methods.

18.
Oxid Med Cell Longev ; 2019: 9151067, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31583050

RESUMO

Background/Aims: Obesity, which is related to increased oxidative stress in various tissues, is a risk factor for male infertility. Metformin is reported to have an antioxidant effect; however, the precise role of metformin in obesity-induced male infertility remains unknown. The current study is aimed at exploring the effects of metformin and characterizing its underlying mechanism in the fertility of obese males. Methods: An obese male mouse model was generated by feeding mice with a high-fat diet; then, the mice were administered metformin in water for 8 weeks. Reproductive ability, metabolic parameters, and follicle-stimulating hormone (FSH) were assessed by cohabitation, enzymatic methods, and ELISA, respectively. Damage to the integrity of the blood-testis barrier (BTB), which ensures spermatogenesis, was assessed by transmission electron microscopy and immunofluorescence with a biotin tracer. Malondialdehyde (MDA), superoxide dismutase (SOD), and reactive oxygen species (ROS) were employed for the assessments of oxidative stress. BTB-related proteins were measured by immunoblotting. Nuclear factor κB (NF-κB) was assessed by immunofluorescence. Results: High-fat-diet-fed mice presented evident lipid metabolic disturbances, disrupted BTB integrity, and decreased reproductive function. Metformin alleviated the decrease in male fertility, decreased ectopic lipid deposition in the testis, and increased serum FSH levels. A further mechanistic analysis revealed that metformin ameliorated the high-fat-diet-induced injury to the BTB structure and permeability and restored the disordered BTB-related proteins, which might be associated with an improvement in oxidative stress and a recovery of NF-κB activity in Sertoli cells (SCs). Conclusion: Metformin improves obese male fertility by alleviating oxidative stress-induced BTB damage. These findings provide new insights into the effect of metformin on various diseases and suggest future possibilities in the treatment of male infertility.

19.
J Magn Reson Imaging ; 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31617290

RESUMO

BACKGROUND: Retinoblastomas (RBs) with postlaminar optic nerve invasion (PLONI) increases the risk of local recurrence or systemic metastasis. Most MRI studies on PLONI focused on optic nerve enhancement and tumor size, with reported relatively high specificity (84-98%) but low sensitivity (37-78%), which shows room for improvement, especially with regard to sensitivity. PURPOSE: To evaluate the diagnostic performance for detecting PLONI with RB using MRI features. STUDY TYPE: Retrospective. POPULATION: Fifty patients with histopathologic PLONI and 70 patients without PLONI of RB. FIELD STRENGTH/SEQUENCE: 1.5T and 3.0T, precontrast axial T1 -weighted and T2 -weighted, postcontrast axial, coronal and oblique-sagittal T1 -weighted. ASSESSMENT: The eyes were histopathologically analyzed and the preoperative MRI features of the eyes were independently evaluated by three observers. STATISTICAL TESTS: MRI features suggesting the presence of PLONI were identified by univariate and multivariable analysis. Receiver operating characteristic curve (ROC) and the area under the curve (AUC) were used to analyze diagnostic performance. RESULTS: Significant independent diagnostic factors for PLONI include: 1: Bilateral tumor (odds ratio [OR], 15.32; 95% confidence interval [CI]: 1.63-143.51); 2: Tumor with total coverage of the optic disk (OR, 6.43; 95% CI: 1.04-39.79); and 3: Optic nerve enhancement (OR, 8.43; 95% CI: 3.50-20.31). On the other hand, isointense signal of tumor on T2 WI (OR, 0.30; 95% CI: 0.12-0.75) was an independent diagnostic factor in excluding PLONI. ROC analysis showed AUC of 0.84 (95% CI: 0.77-0.91, P < 0.0001) for PLONI. Based on the cutoff of maximum Youden index, the sensitivity, specificity, and accuracy were 82%, 73%, and 77%, respectively. DATA CONCLUSION: MRI features of RB showed a strong association with PLONI. The model of MRI features demonstrated promising diagnostic performance in detecting PLONI. LEVEL OF EVIDENCE: 4 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019.

20.
J Dairy Sci ; 102(11): 9639-9650, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31477286

RESUMO

To determine the key aroma compounds in Chinese milk fan cheese, samples from 6 of the most popular handmade milk fan workshops in Yunnan province of China were analyzed by gas chromatography-mass spectrometry (GC-MS), gas chromatography-olfactometry (GC-O), sensory evaluation, aroma recombination and omission experiments. Seventy-one aroma compounds were identified by GC-MS, and 31 odor-active compounds were detected by GC-O. The relationships between the 31 odor-active compounds and 10 sensory evaluation properties were explored by partial least squares discriminant analysis. The results identified 23 initial key aroma compounds, which were used to simulate the aroma profile of milk fan in aroma recombination experiments. Aroma omission experiments identified propanoic acid, butanoic acid, octanoic acid, octanal, nonanal, 2-nonanone, and ethyl hexanoate as the key aroma compounds. Propanoic acid and butanoic acid contributed to cheese and rancid aromas, octanal and nonanal to the fat aroma, octanoic acid and 2-nonanone to the cheese aroma, and ethyl hexanoate to the fruity aroma of milk fan.


Assuntos
Leite/química , Odorantes/análise , Aldeídos/análise , Animais , Bovinos , Queijo/análise , China , Cromatografia Gasosa-Espectrometria de Massas/métodos , Cetonas/análise , Análise dos Mínimos Quadrados , Olfatometria/métodos
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