Depression in Polycystic Ovary Syndrome: Focusing on Pathogenesis and Treatment.

Polycystic ovary syndrome (PCOS) is one of the most prevalent gynecological endocrine conditions affecting reproductive women. It can feature a variety of symptoms, such as obesity, insulin resistance, skin conditions, and infertility. Women with PCOS are susceptible to illnesses including mood disorders, diabetes, hypertension, and dyslipidemia. Among them, depression is the most common in PCOS and has a detrimental effect on quality of life. Depression may occasionally develop due to the pathological traits of PCOS, but its exact pathogenesis in PCOS have eluded researchers to date. Therefore, there is an urgent need to explore the pathogenesis and treatments of depression in PCOS. The present review discusses the epidemiology of depression in PCOS, potential pathogenic mechanisms underlying PCOS and depression, as well as some potential factors causing depression in PCOS, including obesity, insulin resistance, hyperandrogenism, inflammation, and infertility. Meanwhile, some common treatment strategies for depression in PCOS, such as lifestyle intervention, acupuncture, oral contraceptive pills, psychological intervention, and insulin-sensitizer, are also reviewed. To fully understand the pathogenesis and treatment of depression in PCOS, a need remains for future large-scale multi-center randomized controlled trials and in-depth mechanism studies. Appeared originally in Front Psychiatry 2022; 13:1001484.

Best acupuncture method for mammary gland hyperplasia: Evaluation of randomized controlled trials and Bayesian network meta-analysis.

Objective: To evaluate the effectiveness of different acupuncture treatments for mammary gland hyperplasia (MGH) using a network meta-analysis. Methods: Several databases were searched without language restrictions from 2000 to February 2023, including PubMed, Embase, Web of Science, Cochrane Library, China Science and Technology Journal Database, China Biology Medicine Database, Wanfang Database, China National Knowledge Infrastructure Database, and other professional websites and gray literature. Inclusion criteria were adult women diagnosed with MGH; intervention measures included acupuncture and related therapies; the control group was treated with simple drugs; and the research type was a randomized controlled trial (RCT). The primary outcomes were treatment effectiveness and estradiol and progesterone levels. Secondary outcomes were breast lump size and visual analog scale (VAS) score of breast pain. Exclusion criteria were studies unrelated to MGH, incorrect study populations, control measures or interventions, incomplete data, non-RCTs, case reports, and animal experiments. Cochrane tools were used to assess the risk of bias. The R software (x64 version 4.2.1), Review Manager 5.3 software and STATA 16.0 software were used for data analysis. Results: Following a rigorous screening process, data extraction, and quality assessment, 48 eligible RCTs encompassing 4,500 patients with MGH and 16 interventions were included. The results indicated that acupuncture, alone or in combination with traditional Chinese or Western medicine, had better therapeutic effects than conventional therapy. In terms of effectiveness, warm needle acupuncture was the best choice (94.6%). Bloodletting pricking was the most effective method (85.7%) for lowering progesterone levels. Bloodletting pricking was the most effective method (98.3%) for lowering estradiol levels. Manual acupuncture combined with traditional Chinese medicine was the most effective (74.5%) treatment to improve the size of the breast lump. Warm needle acupuncture was the most effective (69.8%) in improving the VAS score. Conclusion: Acupuncture therapy was more effective in treating MGH than drug therapy alone, and warm needle acupuncture and bloodletting pricking were the two best options. However, larger sample sizes and high-quality RCTs are required.

Cuproptosis in stroke: focusing on pathogenesis and treatment.

Annually, more than 15 million people worldwide suffer from stroke, a condition linked to high mortality and disability rates. This disease significantly affects daily life, impairing everyday functioning, executive function, and cognition. Moreover, stroke severely restricts patients' ability to perform daily activities, diminishing their overall quality of life. Recent scientific studies have identified cuproptosis, a newly discovered form of cell death, as a key factor in stroke development. However, the role of cuproptosis in stroke remains unclear to researchers. Therefore, it is crucial to investigate the mechanisms of cuproptosis in stroke's pathogenesis. This review examines the physiological role of copper, the characteristics and mechanisms of cuproptosis, the differences and similarities between cuproptosis and other cell death types, and the pathophysiology of cuproptosis in stroke, focusing on mitochondrial dysfunction and immune infiltration. Further research is necessary to understand the relationship between previous strokes and cuproptosis and to clarify the mechanisms behind these associations.

Investigating the role of mitochondrial DNA D-loop variants, haplotypes, and copy number in polycystic ovary syndrome: implications for clinical phenotypes in the Chinese population.

Background: The presence of genetic variations in mitochondrial DNA (mtDNA) has been associated with a diverse array of diseases. The objective of this study was to examine the correlations between mtDNA D-loop, its haplotypes, and polycystic ovary syndrome (PCOS) in the Chinese population, and the associations between mtDNA D-loop and symptoms of PCOS. The study also sought to determine whether the mtDNA copy number in Chinese patients with PCOS differed from that of individuals in the control group. Methods: Infertile individuals who only had tubal or male factor treatment were the focus of research by The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO). mtDNA haplotypes were categorized using polymorphic D-loop sites. mtDNA D-loop, PCOS features, and mtDNA haplotypes were analyzed using R software to determine the strength of the association between the three. There are certain DNA haplotypes linked to PCOS. Microdroplet digital polymerase chain reaction (PCR) was used to determine the mtDNA copy number in a convenience sample of 168 PCOS patients and 83 controls. Results: Among the research group, the majority of D-loop mutations were infrequent (frequency< 1%), with only 45 variants displaying a minimum allele frequency (MAF) of 5% or higher. No association was found between polymorphism loci in PCOS patients and body mass index (BMI). Noteworthy, C194T, 1A200G, 523delAC, and C16234T showed positive correlations with elevated LH/FSH levels. Additionally, specific polymorphic loci G207A, 16036GGins, and 16049Gins within the D-loop region of mtDNA potentially exerted a protective role in PCOS development. Conversely, no statistical significance was observed in the expression levels of C16291T and T489C. Chinese women with mtDNA haplotype A15 exhibited a decreased risk of developing PCOS. Moreover, a significant difference in mtDNA copy number was detected, with controls averaging 25.87 (21.84, 34.81), while PCOS patients had a mean of 129.91 (99.38, 168.63). Conclusion: Certain mtDNA D-loop mutations and haplotypes appear to confer protection against PCOS in Chinese women. In addition, elevated mtDNA copy number may serve as an indicator during early stages of PCOS.

[Effects of staged acupuncture on endometrial receptivity and anxiety in patients with recurrent implantation failure of thin endometrium based on "thoroughfare vessel is the sea of blood" theory].

OBJECTIVE: To compare the clinical efficacy between staged acupuncture based on "thoroughfare vessel is the sea of blood" theory combined with routine hormone replacement cycle treatment and routine hormone replacement cycle treatment for patients with recurrent implantation failure (RIF) of thin endometrium. METHODS: A total of 72 RIF patients with thin endometrium were randomly divided into an observation group and a control group, 36 cases in each group. The patients in the control group were treated with routine hormone replacement cycle treatment. Based on the treatment of the control group, the patients in the observation group were treated with staged acupuncture based on "thoroughfare vessel is the sea of blood" theory. The main acupoints were Neiguan (PC 6) and Gongsun (SP 4), and the supplementary acupoints were selected according to the menstrual cycle and syndrome differentiation; the acupuncture was given once every other day, 3 times a week, for 3 consecutive menstrual cycles. The thickness and shape of endometrium, and Hamilton anxiety scale (HAMA) score were observed at implantation window before and after treatment; the clinical pregnancy rate, live birth rate and cycle cancellation rate were compared between the two groups; the correlation between endometrial thickness and HAMA score was analyzed. RESULTS: Compared before treatment, the endometrial thickness in the two groups and the proportion of type A+B endometrium in the observation group were increased (P<0.05), and the HAMA scores in the two groups were decreased (P<0.05) after treatment. The above indexes in the observation group were superior to those in the control group (P<0.05). The clinical pregnancy rate and live birth rate in the observation group were higher than those in the control group (P<0.05), and the cycle cancellation rate was lower than that in the control group (P<0.05). There was a negative correlation between endometrial thickness and HAMA score (P<0.05). CONCLUSION: Based on the routine hormone replacement cycle treatment, the addition use of staged acupuncture based on "thoroughfare vessel is the sea of blood" theory could improve the thickness and shape of endometrium, relieve anxiety, increase the clinical pregnancy rate and live birth rate, and reduce the cycle cancellation rate in RIF patients with thin endometrium. The curative effect is superior to the routine hormone replacement cycle treatment alone.

Falls caused by balance disorders in the elderly with multiple systems involved: Pathogenic mechanisms and treatment strategies.

Falls are the main contributor to both fatal and nonfatal injuries in elderly individuals as well as significant sources of morbidity and mortality, which are mostly induced by impaired balance control. The ability to keep balance is a remarkably complex process that allows for rapid and precise changes to prevent falls with multiple systems involved, such as musculoskeletal system, the central nervous system and sensory system. However, the exact pathogenesis of falls caused by balance disorders in the elderly has eluded researchers to date. In consideration of aging phenomenon aggravation and fall risks in the elderly, there is an urgent need to explore the pathogenesis and treatments of falls caused by balance disorders in the elderly. The present review discusses the epidemiology of falls in the elderly, potential pathogenic mechanisms underlying multiple systems involved in falls caused by balance disorders, including musculoskeletal system, the central nervous system and sensory system. Meanwhile, some common treatment strategies, such as physical exercise, new equipment based on artificial intelligence, pharmacologic treatments and fall prevention education are also reviewed. To fully understand the pathogenesis and treatment of falls caused by balance disorders, a need remains for future large-scale multi-center randomized controlled trials and in-depth mechanism studies.

Decomposing the decoupling relationship between energy consumption and economic growth in China's agricultural sector.

Sustainable food supply is affected by high energy consumption and negative environmental effects. Regarding the national strategy of "carbon peaking and carbon neutrality targets", the decoupling between energy consumption and economic growth in China's agriculture has received significant attention. Therefore, this study first presents a descriptive analysis of the energy consumption in China's agricultural sector from 2000 to 2019, before analyzing the decoupling state between energy consumption and agricultural economic growth at the national and provincial levels using the Tapio decoupling index. Finally, the logarithmic mean divisia index method is used to decompose the decoupling driving factors. The study draws the following conclusions: (1) At the national level, the decoupling of agricultural energy consumption from economic growth fluctuates among expansive negative decoupling, expansive coupling, and weak decoupling, before stabilizing in the last state. (2) The decoupling process also differs by geographic region. Strong negative decoupling is found in North and East China, and strong decoupling lasts longer in Southwest and Northwest China. (3) The factors driving decoupling are similar at both the levels. The economic activity effect promotes the decoupling of energy consumption. The industrial structure and energy intensity effects are the two main suppressive factors, whereas the population and energy structure effects have relatively weaker impacts. Therefore, based on the empirical results, this study provides evidence for regional governments to formulate policies on the relationship between the agricultural economy and energy management from the perspective of effect driven policies.

Research progress in the risk factors and screening assessment of dysphagia in the elderly.

With the aging of the population, the incidence of dysphagia has gradually increased and become a major clinical and public health issue. Early screening of dysphagia in high-risk populations is crucial to identify the risk factors of dysphagia and carry out effective interventions and health management in advance. In this study, the current epidemiology, hazards, risk factors, preventive, and therapeutic measures of dysphagia were comprehensively reviewed, and a literature review of screening instruments commonly used globally was conducted, focusing on their intended populations, main indicators, descriptions, and characteristics. According to analysis and research in the current study, previous studies of dysphagia were predominantly conducted in inpatients, and there are few investigations and screenings on the incidence and influencing factors of dysphagia in the community-dwelling elderly and of dysphagia developing in the natural aging process. Moreover, there are no unified, simple, economical, practical, safe, and easy-to-administer screening tools and evaluation standards for dysphagia in the elderly. It is imperative to focus on dysphagia in the community-dwelling elderly, develop unified screening and assessment tools, and establish an early warning model of risks and a dietary structure model for dysphagia in the community-dwelling elderly.

Spatiotemporal Dynamics of Wetland in Dongting Lake Based on Multi-Source Satellite Observation Data during Last Two Decades.

Monitoring the dynamics of wetland resources has practical value for wetland protection, restoration and sustainable utilization. Dongting Lake wetland reserves are well known for both their intra-annual and inter-annual dynamic changes due to the effects of natural or human factors. However, most wetland monitoring research has failed to consider the seasonal wetlands, which is the most fragile wetland type, requiring more attention. In this study, we used multi-source time series remote sensing data to monitor three Dongting Lake wetland reserves between 2000 and 2020, and the seasonal wetlands were separated from permanent wetlands. Multispectral and indices time series were generated at 30 m resolution using a two-month composition strategy; the optimal features were then selected using the extension of the Jeffries-Matusita distance (JBh) and random forest (RF) importance score; yearly wetland maps were identified using the optimal features and the RF classifier. Results showed that (1) the yearly wetland maps had good accuracy, and the overall accuracy and kappa coefficients of all wetland maps from 2000 to 2020 were above 89.6% and 0.86, respectively. Optimal features selected by JBh can improve both computational efficiency and classification accuracy. (2) The acreage of seasonal wetlands varies greatly among multiple years due to inter-annual differences in precipitation and evaporation. (3) Although the total wetland area of the three Dongting Lake wetland reserves remained relatively stable between 2000 and 2020, the acreage of the natural wetland types still decreased by 197.0 km2, and the change from natural wetland to human-made wetland (paddy field) contributed the most to this decrease. From the perspective of the ecological community, the human-made wetland has lower ecological function value than natural wetlands, so the balance between economic development and ecological protection in the three Dongting Lake wetland reserves requires further evaluation. The outcomes of this study could improve the understanding of the trends and driving mechanisms of wetland dynamics, which has important scientific significance and application value for the protection and restoration of Dongting Lake wetland reserves.

Acupuncture Improves Endometrial Angiogenesis by Activating PI3K/AKT Pathway in a Rat Model with PCOS.

Background: Acupuncture, a treatment derived from traditional Chinese medicine, can effectively relieve the symptoms and improve pregnancy outcome in patients with polycystic ovary syndrome (PCOS); however, its mechanism remains unclear. This study aimed at investigating whether acupuncture could improve endometrial angiogenesis and thus endometrial receptivity via activating PI3K/AKT pathway in PCOS rats. Methods: We established a rat model with PCOS, which was induced by DHEA. Acupuncture was performed every other day for 15 days, and the PI3K inhibitor (LY294002) was intraperitoneal injected 30 mins before acupuncture treatment. Females rats were mated with male SPF SD rats in a ratio of 2 : 1 after treatment and sacrificed on the 5th day when the vaginal plug was identified. The number of implantation sites was observed, followed by ovarian and endometrial morphology detected with hematoxylin-eosin staining and a scanning electron microscope, estrous cycle detected with vaginal smear analysis, and sex hormones and angiogenesis-related PI3K/AKT gene/protein expression detected with enzyme-linked immunosorbent assay, western blotting, immune histochemistry, and quantitative real-time PCR. Results: Acupuncture notably improved implantation sites' number, endometrial receptivity factors including endometrial morphology, pinopodes, HOX-10, and LIF protein expression, as well as angiogenesis and PI3K/AKT pathway factors such as VEGF, VEGFR2, Ang-1, PI3K, AKT, and P-AKT gene/protein expression and the level of eNOS and NO in the endometrium of rats with PCOS; PCOS-like symptoms were alleviated as well. The efficacy of acupuncture on a rat model with PCOS was counteracted by the combination with the PI3K inhibitor. Conclusion: Acupuncture improves endometrial angiogenesis by activating the PI3K/AKT pathway, thus promoting endometrial receptivity and the number of implantation sites in rats with PCOS.

Preventive Electroacupuncture Alleviates Oxidative Stress and Inflammation via Keap1/Nrf2/HO-1 Pathway in Rats with Cyclophosphamide-Induced Premature Ovarian Insufficiency.

Electroacupuncture (EA) is a popular therapeutic therapy for premature ovarian insufficiency (POI). However, little has been known about the underlying processes of EA therapy. To investigate the benefit of EA and reveal the mechanism, thirty SD female rats were allocated into the control, model, sham, EA, and GnRHa groups at random. Vaginal smears were used to monitor the rats' estrous cycle. Serum liver and renal function (ALT, AST, BUN, and Cr), sex hormone (FSH, E2, and AMH), oxidative stress markers (SOD, GSH, and MDA), and inflammatory cytokine (IL6, IL1ß, and TNFα) levels were measured by enzyme-linked immunosorbent assay (ELISA). Their ovary morphology was observed by hematoxylin-eosin staining. Transmission electron microscope was used to remark the ultrastructure of the granulocytes. Protein and gene expressions of Keap1/Nrf2/HO-1 pathway were detected by western blot and RT-PCR. Compared with the model group, in the EA group, the levels of serum sex hormones recovered to normal levels. Moreover, it reduced oxidative stress in rats, as demonstrated by increased SOD and GSH levels and decreased MDA levels. Meanwhile, Keap1 mRNA and protein expression dropped considerably in the EA group, while the mRNA and protein expressions of Nrf2 and HO-1 increased. We found that preventive EA might rescue rats with CTX-induced ovarian dysfunction. The anti-inflammatory and antioxidative stress properties of EA, which elevated the Keap1/Nrf2/HO-1 signaling pathway, might be the underlying mechanism. Furthermore, as compared to GnRHa, electroacupuncture did not raise the burden of the liver (ALT and AST) or the kidney (BUN and Cr). Electroacupuncture has a meaningful impact and a sufficient level of safety, making it useful for therapeutic setting in POI.

Depression in polycystic ovary syndrome: Focusing on pathogenesis and treatment.

Polycystic ovary syndrome (PCOS) is one of the most prevalent gynecological endocrine conditions affecting reproductive women. It can feature a variety of symptoms, such as obesity, insulin resistance, skin conditions, and infertility. Women with PCOS are susceptible to illnesses including mood disorders, diabetes, hypertension, and dyslipidemia. Among them, depression is the most common in PCOS and has a detrimental effect on quality of life. Depression may occasionally develop due to the pathological traits of PCOS, but its exact pathogenesis in PCOS have eluded researchers to date. Therefore, there is an urgent need to explore the pathogenesis and treatments of depression in PCOS. The present review discusses the epidemiology of depression in PCOS, potential pathogenic mechanisms underlying PCOS and depression, as well as some potential factors causing depression in PCOS, including obesity, insulin resistance, hyperandrogenism, inflammation, and infertility. Meanwhile, some common treatment strategies for depression in PCOS, such as lifestyle intervention, acupuncture, oral contraceptive pills, psychological intervention, and insulin-sensitizer, are also reviewed. To fully understand the pathogenesis and treatment of depression in PCOS, a need remains for future large-scale multi-center randomized controlled trials and in-depth mechanism studies.

Effect of Acupoint Embedding on Serum Leptin and Hypothalamus Leptin Receptor Expression in Rats with Simple Obesity.

BACKGROUND: Acupoint embedding treatment on obesity has been applied in clinical practice for many years and has achieved obvious efficacy. However, animal experimental studies on acupoint embedding are relatively few, and its mechanism remains unclear. METHODS: We established a simple obese rat model using a high-fat diet for 8 weeks. Acupoint embedding therapy was performed once a week for 4 weeks. After the treatment, serum leptin, triglyceride (TG), cholesterol (TC), low-density lipoprotein (LDL), and high-density lipoprotein (HDL) levels were detected by radioimmunoassay, HE staining was used for fat morphology analysis, and immunohistochemical method was used to detect the expression of leptin receptor in hypothalamus. RESULTS: Compared with model group, acupoint embedding treatment can reduce body weight and Lee's index, reduce serum leptin, TG, TC, and LDL level, increase HDL level, change the morphology and number of adipocytes, and increase the expression of leptin receptor in hypothalamus. CONCLUSION: Acupoint embedding therapy can reduce the level of leptin in blood, increase the number of leptin receptors in hypothalamus, enhance the biological effect of leptin, alleviate the leptin resistance in obese body, change the shape of fat, and regulate the level of blood lipid, so as to achieve the goal of weight loss.

Acupuncture treatment on attention deficit hyperactivity disorder: A protocol for systematic review and meta-analysis.

BACKGROUND: Attention Deficit Hyperactivity Disorder (ADHD) is the most common behavioral disorder in childhood. Acupuncture treatment of ADHD has formed a relatively systematic theoretical and clinical treatment system which achieved satisfactory results. However, there has been no systematic evaluation of its effectiveness and safety. The purpose of this study was to evaluate the efficacy and safety of acupuncture in the treatment of ADHD. METHODS: A systematic search of literature will be conducted in PubMed, Cochrane Library, the Web of Science, Excerpt Medica Database, Chinese Biomedical Literature Database, VIP, Wanfang database, China National Knowledge Infrastructure database for articles published up to September, 2019. The searching terms include "attention deficit", "hyperactivity", "mild brain dysfunction", "acupuncture", "electroacupuncture". The search is limited to studies published in Chinese and English. Two reviewers will extract and evaluate the information independently. Cochrane Collaboration tool and Jadad scale will be used to evaluate the quality of the studies. Review Manager Version 5.3 (Cochrane Collaboration's software) will be used to carry out the meta-analysis. RESULTS: High-quality synthesis and/or descriptive analysis of current evidence will be provided from effective rate, total score of traditional Chinese medicines syndromes, conners child hyperactivity-diagnosis rating scale, conners index of hyperactivity, the recurrence rate, and adverse events. CONCLUSION: This study will provide the evidence of whether acupuncture is an effective and safe intervention to ADHD. INPLASY REGISTRATION NUMBER: INPLASY202140022.

Pregnancy outcome treated with stage-by-stage acupuncture and moxibustion therapy based on the chong channel being sea of blood theory in repeated IVF-ET failure patients: A randomized controlled trial.

INTRODUCTION: Acupuncture and moxibustion has become a commonly used adjuvant treatment method to improve the success rate of in vitro fertilization-embryo transfer (IVF-ET). However, There is still insufficient evidence that acupuncture treatment can improve the local microenvironment of endometrium, the endometrial receptivity, and the pregnancy outcome of patients, which is worthy of further study. METHOD/DESIGN: To investigate the effect of Stage by Stage Acupuncture and Moxibustion Therapy on endometrial receptivity and Pregnancy Outcome based on the theory of "Chong channel being sea of blood," we will conduct a multicenter randomized controlled trial. Inclusion criteria are as follows: infertile women under 45 years of age who received IVF-ET or Intracytoplasmic sperm injection cycles. The study will only be applied to women who have failed repeated implantation, that is, women who have failed 3 or more embryo transplants in the past (existing frozen embryos do not require the retrieval of eggs). Those who are not prepared to receive IVF-ET or are at risk of pregnancy, have a serious medical condition, or are egg donors will be excluded. Subjects will be randomly assigned to either the acupuncture group (IVF-ET plus stage-by-stage acupuncture and moxibustion therapy based on the "Chong channel being sea of blood" theory) or the control group (IVF-ET only). The trial required a total sample size of 246 women to compare endometrial receptivity between the 2 groups. The acupuncture group will receive acupuncture and moxibustion treatment 3 times a week starting from the third day of menstruation in the ovary stimulation cycle. One menstrual cycle was one course of treatment, and a total of 3 menstrual cycles were treated. The main outcome indicator was clinical pregnancy rate. Secondary outcome indicators were the three-dimensional volume blood flow parameters (vascularization index, flow index, and vascularization flow index) of the endometrium, endometrial thickness, endometrial volume, uterine artery PI, RI, and S/D during the "implantation window period" (20-24 days after menstruation in the ovary stimulation cycle). DISCUSSION: This study will provide important evidence for the use of Stage by Stage Acupuncture and Moxibustion Therapy Based on the "Chong Channel Being Sea of Blood" Theory in IVF. TRIAL REGISTRATION: http://www.chictr.org.cn/edit.aspx?pid=28811&htm=4 ID: ChiCTR1800017191 (07/17/2018).

Monitoring monthly surface water dynamics of Dongting Lake using Sentinel-1 data at 10 m.

High temporal resolution water distribution maps are essential for surface water monitoring because surface water exhibits significant inner-annual variation. Therefore, high-frequency remote sensing data are needed for surface water mapping. Dongting Lake, the second-largest freshwater lake in China, is famous for the seasonal fluctuations of its inundation extents in the middle reaches of the Yangtze River. It is also greatly affected by the Three Gorges Project. In this study, we used Sentinel-1 data to generate surface water maps of Dongting Lake at 10 m resolution. First, we generated the Sentinel-1 time series backscattering coefficient for VH and VV polarizations at 10 m resolution by using a monthly composition method. Second, we generated the thresholds for mapping surface water at 10 m resolution with monthly frequencies using Sentinel-1 data. Then, we derived the monthly surface water distribution product of Dongting Lake in 2016, and finally, we analyzed the inner-annual surface water dynamics. The results showed that: (1) The thresholds were -21.56 and -15.82 dB for the backscattering coefficients for VH and VV, respectively, and the overall accuracy and Kappa coefficients were above 95.50% and 0.90, respectively, for the VH backscattering coefficient, and above 94.50% and 0.88, respectively, for the VV backscattering coefficient. The VV backscattering coefficient achieved lower accuracy due to the effect of the wind causing roughness on the surface of the water. (2) The maximum and minimum areas of surface water were 2040.33 km2 in July, and 738.89 km2 in December. The surface water area of Dongting Lake varied most significantly in April and August. The permanent water acreage in 2016 was 556.35 km2, accounting for 19.65% of the total area of Dongting Lake, and the acreage of seasonal water was 1525.21 km2. This study proposed a method to automatically generate monthly surface water at 10 m resolution, which may contribute to monitoring surface water in a timely manner.

Recombinant expression and biological characterization of the antimicrobial peptide fowlicidin-2 in Pichia pastoris.

Fowlicidins are a group of cathelicidin antimicrobial peptides that were initially identified in chickens. Fowlicidin-2, which is composed of 31 amino acids, is widely expressed in the majority of tissues in chickens and has an important role in innate immunity. In the present study, a recombinant expression system for fowlicidin-2 was successfully constructed using Pichia pastoris X-33 and the expression vector pPICZα-A. Under the optimized fermentation conditions, 85.6 mg fowlicidin-2 with >95% purity was obtained from 1 liter culture medium following purification by ion exchange chromatography and reversed phase high performance liquid chromatography. The recombinant fowlicidin-2 exhibited broad spectrum antimicrobial activity and had a minimum inhibitory concentration ranging from 1 to 4 µM. Furthermore, recombinant fowlicidin-2 exhibited hemolytic activity, promoting 50% human erythrocyte hemolysis in the concentration range of 128-256 µM, and anticancer activity, resulting in the death of 50% of A375 human malignant melanoma cells in the concentration range of 2-4 µM. The results of the present study suggest that recombinant fowlicidin-2 may be a promising candidate for therapeutic applications.

Identification of a novel cathelicidin antimicrobial peptide from ducks and determination of its functional activity and antibacterial mechanism.

The family of antimicrobial peptide, cathelicidins, which plays important roles against infections in animals, has been identified from many species. Here, we identified a novel avian cathelicidin ortholog from ducks and named dCATH. The cDNA sequence of dCATH encodes a predicted 146-amino-acid polypeptide composed of a 17-residue signal peptide, a 109-residue conserved cathelin domain and a 20-residue mature peptide. Phylogenetic analysis demonstrated that dCATH is highly divergent from other avian peptides. The α-helical structure of the peptide exerted strong antimicrobial activity against a broad range of bacteria in vitro, with most minimum inhibitory concentrations in the range of 2 to 4 µM. Moreover, dCATH also showed cytotoxicity, lysing 50% of mammalian erythrocytes in the presence or absence of 10% fetal calf serum at concentrations of 32 µM or 20 µM and killing 50% HaCaT cells at a concentration of 10 µM. The effects on bacterial outer and inner membranes, as examined by scanning electron microscope and transmission electron microscopy, indicate that dCATH kills microbial cells by increasing permeability, causing a loss of membrane integrity.

High-yield recombinant expression of the chicken antimicrobial peptide fowlicidin-2 in Escherichia coli.

The antimicrobial peptide fowlicidin-2 identified in chicken is a member of the cathelicidins family. The mature fowlicidin-2 possesses high antibacterial efficacy and lipopolysaccharide (LPS) neutralizing activity, and also represents an excellent candidate as an antimicrobial agent. In the present study, the recombinant fowlicidin-2 was successfully produced by Escherichia coli (E. coli) recombinant expression system. The gene encoding fowlicidin-2 with the codon preference of E. coli was designed through codon optimization and synthesized in vitro. The gene was then ligated into the plasmid pET-32a(+), which features fusion protein thioredoxin at the N-terminal. The recombinant plasmid was transformed into E. coli BL21(DE3) and cultured in Luria-Bertani (LB) medium. After isopropyl-ß-D-thiogalactopyranoside (IPTG) induction, the fowlicidin-2 fusion protein was successfully expressed as inclusion bodies. The inclusion bodies were dissolved and successfully released the peptide in 70% formic acid solution containing cyanogen bromide (CNBr) in a single step. After purification by reverse-phase high-performance liquid chromatography (RP-HPLC), ∼6.0 mg of fowlicidin-2 with purity more than 97% was obtained from 1 litre of bacteria culture. The recombinant peptide exhibited high antibacterial activity against the Gram-positive and Gram-negative bacteria, and even drug-resistant strains. This system could be used to rapidly and efficiently produce milligram quantities of a battery of recombinant antimicrobial peptides as well as for large-scale production.