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Thyroid hormones (THs) play important roles in growth, development, morphogenesis, reproduction, and so on. They are mainly meditated by binding to thyroid hormone receptors (TRs) in vertebrates. As important members of the nuclear receptor superfamily, TRs and their ligands are involved in many biological processes. To investigate the potential roles of TRs in the gonadal differentiation and sex change, we cloned and characterized the TRs genes in protogynous rice field eel (Monopterus albus). In this study, three types of TRs were obtained, which were TRαA, TRαB and TRß, encoding preproproteins of 336-, 409- and 415-amino acids, respectively. Multiple alignments of the three putative TRs protein sequences showed they had a higher similarity. Tissue expression analysis showed that TRαA mainly expressed in the gonad, while TRαB and TRß in the brain. During female-to-male sex reversal, the expression levels of all the three TRs showed a similar trend of increase followed by a decrease in the gonad. Intraperitoneal injection of triiodothyronine (T3) stimulated the expression of TRαA and TRαB, while it had no significant change on the expression of TRß in the ovary. Gonadotropin-releasing hormone analogue (GnRHa) injection also significantly upregulated the expression levels of TRαA and TRαB after 6 h, while it had no significant effect on TRß. These results demonstrated that TRs were involved in the gonadal differentiation and sex reversal, and TRα may play more important roles than TRß in reproduction by the regulation of GnRHa in rice field eel.
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Aiming at the problems of complex structure parameters and low feature extraction ability of U-Net used in vegetation classification, a deep network with improved U-Net and dual-way branch input is proposed. Firstly, The principal component analysis (PCA) is used to reduce the dimension of hyperspectral remote sensing images, and the effective bands are obtained. Secondly, the depthwise separable convolution and residual connections are combined to replace the common convolution layers of U-Net for depth feature extraction to ensure classification accuracy and reduce the complexity of network parameters. Finally, normalized difference vegetation index (NDVI), gray level co-occurrence matrix (GLCM) and edge features of hyperspectral remote sensing images are extracted respectively. The above three artificial features are fused as one input, and PCA dimension reduction features are used as another input. Based on the improved U-net, a dual-way vegetation classification model is generated. Taking the hyperspectral remote sensing image of Matiwan Village, Xiong'an, Beijing as the experimental object, the experimental results show that the precision and recall of the improved U-Net are significantly improved with the residual structure and depthwise separable convolution, reaching 97.13% and 92.36% respectively. In addition, in order to verify the effectiveness of artificial features and dual-way branch design, the accuracy of single channel and the dual-way branch are compared. The experimental results show that artificial features in single channel network interfere with the original hyperspectral data, resulting in reduction of the recognition accuracy. However, the accuracy of the dual-way branch network has been improved, reaching 98.67%. It shows that artificial features are effective complements of network features.
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Phylogenetic structure is a key facet of biodiversity, reflecting the evolutionary history of species, and thus can be used to understand various ecological patterns. Although amphibian phylogenetic structures have been tested across space and time separately, simultaneous quantifications are still needed. In the present study, amphibians in streams of Tianping mountain, China, were selected as the model to investigate their elevational spatial and seasonal temporal patterns of phylogenetic diversity. Specifically, 13 streams located in lowland and highland sites were sampled for amphibians and measured for microhabitat variables in April, June, August, and October 2017, separately. Four phylogenetic structural indices, including Faith's PD, standardized effect size (SES) of Faith's PD, mean pairwise phylogenetic distance index (MPD), and SES.MPD, were calculated. Our results revealed that amphibian phylogenetic patterns were not significantly different between lowland and highland sites, but differed significantly between four seasons, associated with distinct community assembly rules (phylogenetically overdispersed vs. phylogenetically clustered). Importantly, these patterns were strongly determined by microhabitat variables such as rock cover, water temperature, and water depth. Our results provide fundamental knowledge to better protect amphibian diversity. Both elevational and seasonal variations are important to understanding the general patterns of amphibian community assembly rules.
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Background: Hypertensive cerebral small vessel disease (HT-CSVD) is a cerebrovascular clinical, imaging and pathological syndrome caused by hypertension (HT). The condition manifests with lesions in various vessels including intracranial small/arterioles, capillaries, and small/venules. Hypertensive cerebral small vessel disease has complex and diverse clinical manifestations. For instance, it can present as an acute stroke which progresses to cause cognitive decline, affective disorder, unstable gait, dysphagia, or abnormal urination. Moreover, hypertensive cerebral small vessel disease causes 25-30% of all cases of ischemic strokes and more than 50% of all cases of single or mixed dementias. The 1-year recurrence rate of stroke in cerebral small vessel disease patients with hypertension is 14%. In the early stage of development, the symptoms of hypertensive cerebral small vessel disease are concealed and often ignored by patients and even clinicians. Patients with an advanced hypertensive cerebral small vessel disease manifest with severe physical and mental dysfunction. Therefore, this condition has a substantial economic burden on affected families and society. Naotaifang (NTF) is potentially effective in improving microcirculation and neurofunction in patients with ischemic stroke. In this regard, this multicenter randomized controlled trial (RCT) aims to furtherly evaluate the efficacy and safety of naotaifang capsules on hypertensive cerebral small vessel disease. Methods: This study is a multicenter, randomized, double-blind, placebo-controlled clinical trial. A total of 388 eligible subjects were recruited from the First Hospital of Hunan University of Chinese Medicine, Hunan Academy of Chinese Medicine Affiliated Hospital, the First Hospital of Shaoyang University, the First Traditional Chinese Medicine Hospital of Changde, and Jiangmen Wuyi Hospital of Traditional Chinese Medicine from July 2020 to April 2022. After a 4-week run-in period, all participants were divided into the intervention group (represented by Y-T, N-T) and control group (represented by Y-C, N-C); using a stratified block randomized method based on the presence or absence of brain damage symptoms in hypertensive cerebral small vessel disease (represented by Y and N). The Y-T and N-T groups were administered different doses of naotaifang capsules, whereas Y-C and N-C groups received placebo treatment. These four groups received the treatments for 6 months. The primary outcome included Fazekas scores and dilated Virchow-robin spaces (dVRS) grades on magnetic resonance imaging (MRI). The secondary outcomes included the number of lacunar infarctions (LI) and cerebral microbleeds (CMB) on magnetic resonance imaging, clinical blood pressure (BP) level, traditional Chinese medicine (TCM) syndrome scores, mini-mental state examination (MMSE) scale, and safety outcomes. Fazekas scores, dilated Virchow-robin spaces grades, and the number of lacunar infarctions and cerebral microbleeds on magnetic resonance imaging were tested before enrollment and after 6 months of treatment. The clinical blood pressure level, traditional Chinese medicine syndrome scores, mini-mental state examination scale and safety outcomes were tested before enrollment, after 3-month, 6-month treatment and 12th-month follow-up respectively. Conclusion: The protocol will comfirm whether naotaifang capsules reduce Fazekas scores, dilated Virchow-robin spaces grades, and the number of lacunar infarctions and cerebral microbleeds, clinical blood pressure, increase mini-mental state examination scores, traditional Chinese medicine syndrome scores of Qi deficiency and blood stasis (QDBS), and improve the quality of life of subjects. The consolidated evidence from this study will shed light on the benefits of Chinese herbs for hypertensive cerebral small vessel disease, such as nourishing qi, promoting blood circulation and removing blood stasis, and dredging collaterals. However, additional clinical trials with large samples and long intervention periods will be required for in-depth research. Clinical Trial registration: www.chictr.org.cn, identifier ChiCTR1900024524.