ObjectiveThis study leverages structural data from antigen-antibody complexes of the influenza A virus neuraminidase (NA) protein to investigate the spatial recognition relationship between the antigenic epitopes and antibody paratopes. MethodsStructural data on NA protein antigen-antibody complexes were comprehensively collected from the SAbDab database, and processed to obtain the amino acid sequences and spatial distribution information on antigenic epitopes and corresponding antibody paratopes. Statistical analysis was conducted on the antibody sequences, frequency of use of genes, amino acid preferences, and the lengths of complementarity determining regions (CDR). Epitope hotspots for antibody binding were analyzed, and the spatial structural similarity of antibody paratopes was calculated and subjected to clustering, which allowed for a comprehensively exploration of the spatial recognition relationship between antigenic epitopes and antibodies. The specificity of antibodies targeting different antigenic epitope clusters was further validated through bio-layer interferometry (BLI) experiments. ResultsThe collected data revealed that the antigen-antibody complex structure data of influenza A virus NA protein in SAbDab database were mainly from H3N2, H7N9 and H1N1 subtypes. The hotspot regions of antigen epitopes were primarily located around the catalytic active site. The antibodies used for structural analysis were primarily derived from human and murine sources. Among murine antibodies, the most frequently used V-J gene combination was IGHV1-12*01/IGHJ2*01, while for human antibodies, the most common combination was IGHV1-69*01/IGHJ6*01. There were significant differences in the lengths and usage preferences of heavy chain CDR amino acids between antibodies that bind within the catalytic active site and those that bind to regions outside the catalytic active site. The results revealed that structurally similar antibodies could recognize the same epitopes, indicating a specific spatial recognition between antibody and antigen epitopes. Structural overlap in the binding regions was observed for antibodies with similar paratope structures, and the competitive binding of these antibodies to the epitope was confirmed through BLI experiments. ConclusionThe antigen epitopes of NA protein mainly ditributed around the catalytic active site and its surrounding loops. Spatial complementarity and electrostatic interactions play crucial roles in the recognition and binding of antibodies to antigenic epitopes in the catalytic region. There existed a spatial recognition relationship between antigens and antibodies that was independent of the uniqueness of antibody sequences, which means that antibodies with different sequences could potentially form similar local spatial structures and recognize the same epitopes.

Defensive behaviors induced by innate fear or Pavlovian fear conditioning are crucial for animals to avoid threats and ensure survival. The zona incerta (ZI) has been demonstrated to play important roles in fear learning and fear memory, as well as modulating auditory-induced innate defensive behavior. However, whether the neuronal subtypes in the ZI and specific circuits can mediate the innate fear response is largely unknown. Here, we found that somatostatin (SST)-positive neurons in the rostral ZI of mice were activated by a visual innate fear stimulus. Optogenetic inhibition of SST-positive neurons in the rostral ZI resulted in reduced flight responses to an overhead looming stimulus. Optogenetic activation of SST-positive neurons in the rostral ZI induced fear-like defensive behavior including increased immobility and bradycardia. In addition, we demonstrated that manipulation of the GABAergic projections from SST-positive neurons in the rostral ZI to the downstream nucleus reuniens (Re) mediated fear-like defensive behavior. Retrograde trans-synaptic tracing also revealed looming stimulus-activated neurons in the superior colliculus (SC) that projected to the Re-projecting SST-positive neurons in the rostral ZI (SC-ZIr^SST-Re pathway). Together, our study elucidates the function of SST-positive neurons in the rostral ZI and the SC-ZIr^SST-Re tri-synaptic circuit in mediating the innate fear response.
Mice ; Animals ; Zona Incerta/metabolism* ; Neurons/metabolism* ; Fear/physiology* ; Somatostatin/metabolism*

Licking behavior is important for water intake. The deep mesencephalic nucleus (DpMe) has been implicated in instinctive behaviors. However, whether the DpMe is involved in licking behavior and the precise neural circuit behind this behavior remains unknown. Here, we found that the activity of the DpMe decreased during water intake. Inhibition of vesicular glutamate transporter 2-positive (VGLUT2⁺) neurons in the DpMe resulted in increased water intake. Somatostatin-expressing (SST⁺), but not protein kinase C-δ-expressing (PKC-δ⁺), GABAergic neurons in the central amygdala (CeA) preferentially innervated DpMe VGLUT2⁺ neurons. The SST⁺ neurons in the CeA projecting to the DpMe were activated at the onset of licking behavior. Activation of these CeA SST⁺ GABAergic neurons, but not PKC-δ⁺ GABAergic neurons, projecting to the DpMe was sufficient to induce licking behavior and promote water intake. These findings redefine the roles of the DpMe and reveal a novel CeA^SST-DpMe^VGLUT2 circuit that regulates licking behavior and promotes water intake.

Aim To explore the effects of Panax notog- inseng saponins( PNS) on hematopoietic functions anrl regulation on the TLR4/TLR2-NF-kB signaling path¬way in immune-mediated aplastic anemia ( AA ) C57 mice.Methods C57BL/6 mice were randomly divid¬ed into control group, total body irradiation group ( TBI) , model group, cyclosporine treatment group, PNS low-dose group, medium-dose group and high-dose group.The immune-mediated A A mice model was es¬tablished by total body irradiation with 5.0 Gy X-ray and mixed lymphocyte infusion.The body weight was measured, the spleen and thymus index was calculated , bone marrow pathology, the levels of peripheral blood triline cells,bone marrow nucleated cells( BMCs) and the levels of serum TNF-cx , 1L-2 , 1L-10 were detected, and the expression of CD1 lc and proteins related to the TLR4/TLR2-N F- k B pathway were detected 15 days later.Results Compared with control group, body weight, thymus index, the number of peripheral blood triline cells, BMCs and serum 1L-10 levels of the mice in model group significantly decreased ( P < 0.05 ) , while spleen index, the serum TNF-a, IL-2 levels and the protein expression of CD 11 c, TLR4, TLR2 , MvD88 , Akt and NF-kB in hone marrow significantly increased ( P <0.05).Compared with model group, after PNS treatment, hodv weight, thymus index, the number of peripheral blood triline cells, BMCs and serum IL-10 levels increased.Spleen index,serum TNF-cx,lL-2 lev¬els and the expression of CD11 c, TLR4, TLR2, NF-kB and Akt in bone marrow decreased, and the therapeutic effect was not dose-dependent.There was no signifi¬cant change in the expression of MvD88 and MAPK proteins.Conclusions PNS can improve AA bone marrow injury, regulate immune disoders and promote hematopoiesis, which may be related to the regulation of the number of DCs and the TLH4/TLH2 - Akt- NF-kB pathway in bone marrow.

ObjectiveTo explore the role of microRNA-99b-5p （miR-99b-5p） in cardiomyocyte hypertrophy and the related mechanism involved. MethodsThe expression of miR-99b-5p in myocardium was detected by real-time quantitative PCR（RT-qPCR）in the myocardium of patients with heart failure（HF）and healthy controls， as well as in the myocardium of mouse model of transverse aortic restriction （TAC）-induced cardiac hypertrophy. Phalloidin-iFluor 647 staining was used to show the size of neonatal mouse ventricular cardiomyocytes（NMVCs）after AngⅡ treatment. MiR-99b-5p expression was determined by RT-qPCR in AngⅡ-treated NMVCs. After transfection with miR-99b-5p mimic， the expression of cardiac hypertrophy-associated genes and Fgf21 in NMVCs was detected by RT-qPCR and Western blot assay， respectively. We identified the interaction between miR-99b-5p and the 3’UTR of Fgf21 mRNA by dual luciferase reporter assay. The recombinant Ffg21 adenovirus（rAd-Fgf21）and rAd-Sod2 were used to infect NMVCs， and the expression of β-MHC， ANP， FGF21 and SOD2 was detected by Western blot assay. We knocked down Fgf21 and Sod2 in NMVCs to investigate the role of FGF21/Sod2 axis in miR-99b-5p-regulated NMVC hypertrophy. ResultsMiR-99b-5p expression was elevated in the myocardium of HF patients and TAC-operated mice， and in AngⅡ-treated NMVCs （P＜0.01， respectively）. MiR-99b-5p promoted the expression of hypertrophy-related genes in NMVCs （P＜0.01）. Results of dual luciferase reporter gene assay revealed the interaction between miR-99b-5p and Fgf21 mRNA. MiR-99b-5p down-regulated the expression of Fgf21 and the down-stream gene of Sod2（ P＜0.01）. Overexpression of FGF21 or SOD2 could inhibit NMVC hypertrophy and effectively reversed the pro-hypertrophy effect of miR-99b-5p on NMVCs （P＜0.05， respectively）. ConclusionMiR-99b-5p is up-regulated in the hypertrophic myocardium and enhances cardiomyocyte hypertrophy via suppressing Fgf21/Sod2 axis.

Melasma， as a kind of melanosis， often occurs over the face of young and middle-aged women， which seriously affects the physical and mental health of patients. At present， it is believed that the occurrence of melasma is related to various factors such as ultraviolet radiation and changes in sex hormone levels in the body. However， the exact pathogenesis of melasma is still unclear and its clinical efficacy is not ideal. Therefore， it is of great clinical significance and social value to carry out basic researches on melasma diseases. Among them， the animal model of melasma acts as an important tool for studying melasma， and it is particularly important to clarify the pathophysiological mechanism of the occurrence and development of melasma. The common modeling methods include ultraviolet modeling， progesterone modeling and ultraviolet combined with progesterone modeling. However， there are still some problems in the practical application of animal models of melasma due to many influencing factors in the preparation of such animal models， and there is still a lack of a more complete and recognized model preparation scheme to this day， which reduces the success rate of model preparation and limits its application and popularization to some extent. In view of the key problems in the establishment and application of animal models of melasma， we comprehensively summarized the research status of the models from such aspects as experimental animals， modeling methods and model evaluation， and discussed the effects of different modeling methods and animal species， animal age and other factors on animal model of melasma by referring to and sorting out the recent literatures at home and abroad in recent years. This is to provide references for the preparation of more scientific， reasonable， economic and convenient animal models of melasma， lay a foundation for in-depth researches on the pathogenesis， prevention and treatment of melasma， and also provide reference for other animal model research.

Pinellia ternata is a medicinal herb of Araceae, and its tubers are used as medicines. It is a common Chinese herbal medicine in China and has a large market demand. When exposing to strong light intensity and high temperature during the growth process, P. ternata withers in a phenomenon known as "sprout tumble", which largely limits tuber production. Shade can effectively delay sprout tumble formation and increase its yield, however the relevant regulation mechanism is unclear. DNA methylation, as a self-modifying response to environmental changes, is often involved in the regulation of plant growth and development. In this study, P. ternata grown under natural light and 90% shading were selected as the control group and the experimental group for genomic DNA methylation analysis by using methylate sensitive amplification polymorphism(MSAP). The results showed that a total of 617 loci were detected with 20 pairs of primers, of which 311 were in the natural light group and 306 in the shading group. The methylation sites in the light and shading groups accounted for 58.2% and 71.57%, respectively, and the methylation ratios in the methylation sites were 27.65% and 29.41%, respectively, indicating that shading significantly induced the genome DNA methylation of P. ternata. Compared to the natural light group, shading promoted 32.51% of the genes methylation, while inducing 16.25% gene demethylation. This study reveals the DNA methylation variation of P. ternata under shading conditions, which lays a preliminary theoretical foundation for further analysis of the mechanism of shading regulation of P. ternata growth from epigenetic level.
China ; DNA Methylation ; Darkness ; Epigenesis, Genetic ; Pinellia/radiation effects* ; Plants, Medicinal/radiation effects* ; Sunlight

Objective:Define traditional Chinese medicine (TCM) therapeutic principles and methods and common prescriptions of benign prostatic hyperplasia (BPH) based on clinical experience of famous doctors. Method:China National Knowledge Infrastructure, China Biology Medicine disc, China Science and Technology Journal Database, Wanfang database were systematically retrieved for literatures of famous doctors in diagnosis and treatment of BPH from January 1, 1997 to December 31, 2018.A literature analysis database was established for integration and analysis of relevant content of TCM therapeutic principles and methods and prescriptions. SPSS 20.0 software was used for statistics to obtain TCM therapeutic principles and methods, common prescriptions and drug distribution regularity of BPH. Result:A total of 109 qualified literatures were included in this study, involving 66 famous doctors and experts, and 9 kinds of BPH therapeutic principles were obtained, including "treatment of both symptoms and root cause of disease", "tonification and purgation in combination", "coordination of Yin and Yang". There are 55 kinds of therapies, including "promoting blood circulation for removing blood stasis", "clearing heat and promoting dampness", "warming and recuperating kidney Yang", "softening and resolving hard mass" and " invigorating kidney Qi". And BPH was mostly diagnosed and treated based on kidney, spleen and lung. Through collection and summarization, totally 38 formulas commonly used in treating BPH obtained. The most commonly used ones were "Guizhi Fuling Wan", "Zishen Tongguan Wan", "Buzhong Yiqi Tang", " Bazheng Tang" and "Jisheng Shenqi Wan". There were 217 commonly used herbs, mainly including " Astragali Radix", "Rehmanniae Radix Praeparata", "Atractylodis Macrocephalae Rhizoma", "Glycyrrhizae Radix et Rhizoma", "Angelicae Sinensis Radix", "Radix Achyranthis Bidentatae", "Peach Kernel", "Pangolin Scales", "Vaccariae Semen", "Salviae Miltiorrhizae Radix et Rhizoma", "Poria", "Rhizoma Alismatis" and "Plantain Seed". Conclusion:The treatment of BPH is based on the principles of "treatment of both symptoms and root cause of disease, and tonification and purgation in combination". The commonly used therapies include prescription for "promoting blood circulation for removing blood stasis", "clearing heat and promoting dampness" and "warming and recuperating kidney Yang". The corresponding prescriptions shall be based on symptoms.

Objective To understand the intention to quit smoking and its influencing factors among current smokers in Gansu Province, so as to provide scientific basis for tobacco control. Methods A multi-stage sampling method was used to extract current smokers aged 15-69 years, and a face-to-face survey was conducted using the questionnaire on smoking among residents in China. Intention to quit smoking between current smokers with different characteristics was analyzed. Logistic regression was used to explore influencing factors of intention to quit smoking. Results The intention of current smokers to quit smoking in Gansu Province was 16.4% (95% CI:15.5%-17.3%). Multivariate logistic regression analysis showed that current smokers who were in rural areas (OR=1.199, 95% CI:1.022-1.408, P=0.026); family smoking prohibited (OR=1.767, 95% CI: 1.273-2.454, P=0.001), medical staff discouraged smoking within 12 months (OR=1.599, 95% CI:1.359-1.842, P<0.001), visited smoking clinics (OR=3.089, 95% CI:2.031-4.698, P＜001), higher educational level of junior high school, senior high school and college or above (OR=1.383, 95% CI:1.101-1.736; OR=1.627, 95% CI:1.252-2.116; OR=1.374, 95% CI:1.009-1.873, all P<0.05), tobacco hazards knowledge with higher scores of 1-, 3- and 5-6 (OR=1.248, 95% CI:1.030-1.514; OR=1.574, 95% CI:1.289-1.922; OR=2.288, 95% CI:1.879-2.786, all P<0.05) were more likely to quit smoking; furthermore, smokers aged 20-, 30- years or smoking 20-, 30- years had a lower chance of quit smoking (all P<0.05). Conclusions The intention of current smokers to quit smoking in Gansu province is generally not high. In the future, knowledge of tobacco hazards should be further promoted, medical staff should provide more smoking cessation services during the treatment process, and more smoking cessation clinics should be established.