New recognition of the heart-brain axis and its implication in the pathogenesis and treatment of PTSD.

Post-traumatic stress disorder (PTSD) is a complex psychological disorder provoked by distressing experiences, and it remains without highly effective intervention strategies. The exploration of PTSD's underlying mechanisms is crucial for advancing diagnostic and therapeutic approaches. Current studies primarily explore PTSD through the lens of the central nervous system, investigating concrete molecular alterations in the cerebral area and neural circuit irregularities. However, the body's response to external stressors, particularly the changes in cardiovascular function, is often pronounced, evidenced by notable cardiac dysfunction. Consequently, examining PTSD with a focus on cardiac function is vital for the early prevention and targeted management of the disorder. This review undertakes a comprehensive literature analysis to detail the alterations in brain and heart structures and functions associated with PTSD. It also synthesizes potential mechanisms of heart-brain axis interactions relevant to the development of PTSD. Ultimately, by considering cardiac function, this review proposes novel perspectives for PTSD's prophylaxis and therapy.

Emerging Omicron subvariants evade neutralizing immunity elicited by vaccine or BA.1/BA.2 infection.

The newly emerging severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron BA.2.75 and BA.2.76 subvariants contained 35 and 29 additional mutations in its spike (S) protein compared with the reference SARS-CoV-2 genome, respectively. Here, we measured the evasion degree of the BA.1, BA.2, BA.4, BA.5, BA.2.75, and BA.2.76 subvariants from neutralizing immunity in people previously infected with the Omicron BA.1 and BA.2, determined the effect of vaccination on immune evasion, and compared the titers of neutralizing antibodies in serums between acute infection and convalescence. Results showed that the neutralization effect of serums from patients with different vaccination statuses and BA.1/BA.2 breakthrough infection decreased with the Omicron evolution from BA.1 to BA.2, BA.4, BA.5, BA.2.75, and BA.2.76. This study also indicated that the existing vaccines could no longer provide effective protection, especially for the emerging BA.2.75 and BA.2.76 subvariants. Therefore, vaccines against emerging epidemic strains should be designed specifically. In the future, we can not only focus on the current strains, but also predict and design new vaccines against potential mutant strains. At the same time, we can combine the virus strains' infection characteristics to develop protective measures for virus colonization areas, such as nasal protection spray. Besides, further studies on the Y248N mutation of BA.2.76 subvariant were also necessary to explore its contribution to the enhanced immune evasion ability.

Evidence for human infection with avian influenza A(H9N2) virus via environmental transmission inside live poultry market in Xiamen, China.

H9N2 avian influenza virus (AIV) has become prevalent in the live poultry market (LPM) worldwide, and environmental transmission mode is an important way for AIVs to infect human beings in the LPM. To find evidence of human infection with the influenza A(H9N2) virus via environmental contamination, we evaluated one human isolate and three environmental isolates inside LPMs in Xiamen, China. The phylogeny, transmissibility, and pathogenicity of the four isolates were sorted out systematically. As for the H9N2 virus, which evolved alongside the "Avian-Environment-Human" spreading chain in LPMs from the summer of 2019 to the summer of 2020, its overall efficiency of contact and aerosol transmissibility improved, which might contribute to the increasing probability of human infection. This study indicated that environmental exposure might act as an important source of human infection in LPMs.

Transmission and prevention of SARS-CoV-2.

The coronavirus disease 2019 (COVID-19), caused by a novel virus of the ß-coronavirus genus (SARS-CoV-2), has been spreading globally. As of July 2020, there have been more than 17 million cases worldwide. Determining multiple transmission routes of SARS-CoV-2 is critical to improving safety practices for the public and stemming the spread of SARS-CoV-2 effectively. This article mainly focuses on published studies on the transmission routes of SARS-CoV-2 including contact transmission, droplet transmission, aerosol transmission and fecal-oral transmission, as well as related research approaches, such as epidemiological investigations, environmental sampling in hospitals and laboratories and animal models. We also provide four specific recommendations for the prevention and control of SARS-CoV-2 that may help reduce the risk of SARS-CoV-2 infection under different environmental conditions. First, social distancing, rational use of face masks and respirators, eye protection, and hand disinfection for medical staff and the general public deserve further attention and promotion. Second, aerodynamic characteristics, such as size distribution, release regularity, aerosol diffusion, survival and decline, infectious dose and spread distance, still require further investigation in order to identify the transmissibility of COVID-19. Third, background monitoring of the distribution of pathogenic microorganisms and environmental disinfection in crowded public places, such as railway stations, schools, hospitals and other densely populated areas, can give early warning of outbreaks and curb the transmission routes of SARS-CoV-2 in those high-risk areas. Forth, establishing novel predictive models can help us to not only assess transmission and impacts in communities, but also better implement corresponding emergency response measures.

A Rapid Screen for Host-Encoded miRNAs with Inhibitory Effects against Ebola Virus Using a Transcription- and Replication-Competent Virus-Like Particle System.

MicroRNAs (miRNAs) may become efficient antiviral agents against the Ebola virus (EBOV) targeting viral genomic RNAs or transcripts. We previously conducted a genome-wide search for differentially expressed miRNAs during viral replication and transcription. In this study, we established a rapid screen for miRNAs with inhibitory effects against EBOV using a tetracistronic transcription- and replication-competent virus-like particle (trVLP) system. This system uses a minigenome comprising an EBOV leader region, luciferase reporter, VP40, GP, VP24, EBOV trailer region, and three noncoding regions from the EBOV genome and can be used to model the life cycle of EBOV under biosafety level (BSL) 2 conditions. Informatic analysis was performed to select up-regulated miRNAs targeting the coding regions of the minigenome with the highest binding energy to perform inhibitory effect screening. Among these miRNAs, miR-150-3p had the most significant inhibitory effect. Reverse transcription polymerase chain reaction (RT-PCR), Western blot, and double fluorescence reporter experiments demonstrated that miR-150-3p inhibited the reproduction of trVLPs via the regulation of GP and VP40 expression by directly targeting the coding regions of GP and VP40. This novel, rapid, and convenient screening method will efficiently facilitate the exploration of miRNAs against EBOV under BSL-2 conditions.

Novel mechanisms of Anshen Dingzhi prescription against PTSD: Inhibiting DCC to modulate synaptic function and inflammatory responses.

ETHNOPHARMACOLOGICAL RELEVANCE: Anshen Dingzhi prescription (ADP), documented in "Yi Xue Xin Wu", is a famous prescription for treating panic-related mental disorders such as post-traumatic stress disorder (PTSD). However, the underlying mechanism remains unclear. AIM OF THE STUDY: This study aimed to investigate the mechanisms by which ADP intervened in PTSD-like behaviors. METHODS: A mouse model of single prolonged stress (SPS) was established to evaluate the ameliorative effects and mechanisms of ADP on PTSD. Behavioral tests were used to assess PTSD-like behaviors in mice; transmission electron microscopy was used to observe changes in the ultrastructure of hippocampal synapses, and western blot, immunofluorescence, and ELISA were used to detect the expression of hippocampal deleted in colorectal cancer (DCC) and downstream Ras-related C3 botulinum toxin substrate 1 (Rac1) - P21-activated kinase 1 (PAK1) signal, as well as levels of synaptic proteins and inflammatory factors. Molecular docking technology simulated the binding of potential brain-penetrating components of ADP to DCC. RESULTS: SPS induced PTSD-like behaviors in mice and increased expression of hippocampal netrin-1 (NT-1) and DCC on the 14th day post-modeling, with concurrent elevation in serum NT-1 levels. Simultaneously, SPS also decreased p-Rac1 level and increased p-PAK1 level, the down-stream molecules of DCC. Lentiviral overexpression of DCC induced or exacerbated PTSD-like behaviors in control and SPS mice, respectively, whereas neutralization antibody against NT-1 reduced DCC activation and ameliorated PTSD-like behaviors in SPS mice. Interestingly, downstream Rac1-PAK1 signal was altered according to DCC expression. Moreover, DCC overexpression down-regulated N-methyl-d-aspartate (NMDA) receptor 2A (GluN2A) and postsynaptic density 95 (PSD95), up-regulated NMDA receptor 2B (GluN2B) and increased neuroinflammatory responses. Administration of ADP (36.8 mg/kg) improved PTSD-like behaviors in the SPS mice, suppressed hippocampal DCC, and downstream Rac1-PAK1 signal, upregulated GluN2A and PSD95, downregulated GluN2B, and reduced levels of inflammatory factors NOD-like receptor protein 3 (NLRP3), nuclear factor kappa-B (NF-κB) and interleukin-6 (IL-6). Importantly, DCC overexpression could also reduce the ameliorative effect of ADP on PTSD. Additionally, DCC demonstrated a favorable molecular docking pattern with the potential brain-penetrating components of ADP, further suggesting DCC as a potential target of ADP. CONCLUSION: Our data indicate that DCC is a key target for the regulation of synaptic function and inflammatory response in the onset of PTSD, and ADP likely reduces DCC to prevent PTSD via modulating downstream Rac1-PAK1 pathway. This study provides a novel mechanism for the onset of PTSD and warrants the clinical application of ADP.

Exploring research hotspots and emerging trends in neuroimaging of vascular cognitive impairment: a bibliometric and visualized analysis.

Background: Vascular cognitive impairment (VCI) manifests in memory impairment, mental slowness, executive dysfunction, behavioral changes, and visuospatial abnormalities, significantly compromising the quality of daily life for patients and causing inconvenience to caregivers. Neuroimaging serves as a crucial approach to evaluating the extent, location, and type of vascular lesions in patients suspected of VCI. Nevertheless, there is still a lack of comprehensive bibliometric analysis to discern the research status and emerging trends concerning VCI neuroimaging. Objective: This study endeavors to explore the collaboration relationships of authors, countries, and institutions, as well as the research hotspots and frontiers of VCI neuroimaging by conducting a bibliometric analysis. Methods: We performed a comprehensive retrieval within the Core Collection of Web of Science, spanning from 2000 to 2023. After screening the included literature, CiteSpace and VOSviewer were utilized for a visualized analysis aimed at identifying the most prolific author, institution, and journal, as well as extracting valuable information from the analysis of references. Results: A total of 1,024 publications were included in this study, comprising 919 articles and 105 reviews. Through the analysis of keywords and references, the research hotspots involve the relationship between neuroimaging of cerebral small vessel disease (CSVD) and VCI, the diagnosis of VCI, and neuroimaging methods pertinent to VCI. Moreover, potential future research directions encompass CSVD, functional and structural connectivity, neuroimaging biomarkers, and lacunar stroke. Conclusion: The research in VCI neuroimaging is constantly developing, and we hope to provide insights and references for future studies by delving into the research hotspots and frontiers within this field.

Effect of acupuncture on post-stroke dysphagia: a randomized controlled trial.

Introduction: Post-stroke dysphagia (PSD) is associated with various complications that increase morbidity and mortality rates. Acupuncture has been used extensively in China to treat these complications; however, its therapeutic efficacy remains uncertain. We therefore aimed to study the clinical effects of acupuncture on PSD. Methods: Patients (n = 101) were randomly divided into acupuncture (n = 50) and rehabilitation training control (n = 51) groups based on the treatment used. Both groups were treated once daily, 6 days a week, for a total of 4 weeks. Pulse oxygen saturation (SpO2) and standardized swallowing assessment (SSA) were performed before the intervention, 2 weeks into treatment, after the intervention (4 weeks post-intervention), and at a 6-month follow-up (28 weeks). The levels of hemoglobin (Hb) and albumin (ALB), and 5-hydroxytryptamine (5-HT) and dopamine (DA) were measured before the intervention, 2 weeks into treatment, and after the intervention (4 weeks), as nutrition and swallowing function indices, respectively. Results: Following the intervention, significant differences were observed between the acupuncture and control groups. The acupuncture group exhibited considerably superior enhancements in SpO2 and SSA scores at 4 weeks (p < 0.001). Moreover, this group demonstrated significantly greater improvements in Hb, ALB, 5-HT, and DA values 4 weeks post-treatment (p < 0.001). However, sex-based differences were not observed (P > 0.005). Conclusion: Acupuncture treatment can improve the swallowing function and nutritional status of patients with PSD, and increase the levels of 5-HT and DA. These findings strongly support the efficacy of acupuncture as a therapeutic intervention in patients with PSD.Clinical trial registration: identifier, ChiCTR2100052201. (https://www.chictr.org.cn/).

Research hotspots and trends in post-stroke dysphagia: a bibliometric analysis.

Background: Dysphagia represents one of the common complications following a stroke, and post-stroke dysphagia (PSD) can lead to aspiration, pneumonia, and malnutrition, thus prolonging hospital stay, escalating medical expenditures, and imposing a substantial economic strain on both patients and society. The utilization of bibliometric analysis offers a quantitative approach for investigating the existing literature and recognizes the current status of the research. However, bibliometric analysis on the subject of PSD remains absent. Consequently, we carried out this study to provide researchers with insights, facilitating their further exploration of PSD. Methods: Conducting a bibliometric analysis of articles pertaining to PSD retrieved over the past two decades enables us to acquire the research hotspots and trends in this area. The publications concerning PSD were searched from the Core Collection of Web of Science, spanning the period ranging from 2003 to 2023. Articles or reviews published in English were included in this study. Subsequently, we employed CiteSpace and VOSviewer software to visualize the retrieved articles, thereby identifying the cooperative relationships of authors, institutions, and countries, as well as relevant information about journals and references. Results: This study comprised 866 papers in total, and the number of articles published each year shows an overall growth trend. As for the analysis of the authors, Dziewas R. was the most prolific author with 21 articles. The most frequently published institutions, countries, and journals were the University of Manchester, China, and Dysphagia, with 28, 254, and 75 publications, respectively. And the co-cited authors and journals with the highest counts were Martino R and Stroke. According to the analysis of keywords and references, dysphagia screening and assessment, prevention of pneumonia, rehabilitation approaches, and nutritional management of PSD are considered research hotpots. Additionally, future research may focus on the topics of systematic review and meta-analysis, noninvasive brain stimulation, and lesion location. Conclusion: Through the bibliometrics analysis of PSD, we can capture the research hotspots and frontiers of PSD, thereby providing inspiration and reference for subsequent studies in this field.

Electroacupuncture attenuates myocardial ischemia-reperfusion injury by inhibiting microglial engulfment of dendritic spines.

A major side effect of reperfusion therapy following myocardial infarction is myocardial ischemia-reperfusion injury (MIRI). Electroacupuncture preconditioning (EA-pre) has a long history in the treatment of cardiovascular diseases. Here, we demonstrate how EA-pre attenuates MIRI by affecting the phagocytosis of neuronal dendritic spines of microglia of the fastigial nucleus (FNmicroglia). We observed that EA-pre increased activity in FNGABA and then improved myocardial injury by inhibiting abnormal activities of glutaminergic neurons of the FN (FNGlu) during MIRI. Interestingly, we observed changes in the quantity and shape of FN microglia in mice treated with EA-pre and a decrease in the phagocytosis of FNGABA neuronal dendritic spines by microglia. Furthermore, the effects of improving MIRI were reversed when EA-pre mice were chemically activated by intra-FN lipopolysaccharide injection. Overall, our results provide new insight indicating that EA-pre regulates microglial engulfment capacity, thus promoting the improvement of cardiac sympathetic nervous disorder during MIRI.

Visualization of the infection risk assessment of SARS-CoV-2 through aerosol and surface transmission in a negative-pressure ward.

Since December 2019, coronavirus disease (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has become a great challenge to the world's public health system. Nosocomial infections have occurred frequently in medical institutions worldwide during this pandemic. Thus, there is an urgent need to construct an effective surveillance and early warning system for pathogen exposure and infection to prevent nosocomial infections in negative-pressure wards. In this study, visualization and construction of an infection risk assessment of SARS-CoV-2 through aerosol and surface transmission in a negative-pressure ward were performed to describe the distribution regularity and infection risk of SARS-CoV-2, the critical factors of infection, the air changes per hour (ACHs) and the viral variation that affect infection risk. The SARS-CoV-2 distribution data from this model were verified by field test data from the Wuhan Huoshenshan Hospital ICU ward. ACHs have a great impact on the infection risk from airborne exposure, while they have little effect on the infection risk from surface exposure. The variant strains demonstrated significantly increased viral loads and risks of infection. The level of protection for nurses and surgeons should be increased when treating patients infected with variant strains, and new disinfection methods, electrostatic adsorption and other air purification methods should be used in all human environments. The results of this study may provide a theoretical reference and technical support for reducing the occurrence of nosocomial infections.

[Moxibustion relieves abdominal hypersensitivity and diarrhea by regulating colonic 5-hydroxytryptamine signaling pathway in rats with diarrhea type irritable bowel syndrome].

OBJECTIVE: To observe the effect of moxibustion on visceral pain, diarrhea, colonic 5-hydroxytryptamine (5-HT) content, and expression of tryptophan hydroxylase 1 (TPH1), serotonin reup take transporter (SERT) and 5-hydroxytryptamine receptor 3 (5-HT3R) in colon tissue of rats with diarrhea irritable bowel syndrome (IBS-D), so as to reveal its underlying mechanisms in treating IBS-D. METHODS: Thirty male SD rats were randomly divided into blank control, model and moxibustion groups (n＝10 rats in each group). The IBS-D model was established by chronic restraint combined with gavage of Senna leaf solution. Moxibustion was applied to bilateral "Tianshu" (ST25) and "Shangjuxu" (ST37) for 30 min, once a day for 7 days. After the treatment, the loose stool rate (number of loose stool/total number of feces granules X100%) and the minimum volume threshold of abdominal reflex (abdominal pain threshold) induced by rectal dilatation were observed. The content of colonic 5-HT was detected by using ELISA, and the expression of TPH1, SERT and 5-HT3R mRNAs and proteins were detected by using quantitative real time-PCR and Western blot, respectively. RESULTS: Compared with the blank control group, the minimum volume threshold of abdominal retraction reflex and the relative expression of SERT protein and mRNA were significantly decreased (P<0.01), and the loose stool rate, colonic 5-HT content, and relative expression of TPH1 and 5-HT3R proteins and mRNAs were notably increased in the model group (P<0.01). After moxibustion, both the decrease of minimum volume threshold and SERT protein and mRNA expressions and the increase of loose stool rate, colonic 5-HT content and TPH1 and 5-HT3R protein and mRNA expressions were reversed (P<0.01). CONCLUSION: Moxibustion of ST25 and ST37 can relieve abdominal hypersensitivity and diarrhea in IBS-D model rats, which is related to its effects in down-regulating colonic 5-HT content and expression of TPH1 and 5-HT3R proteins and mRNAs and in up-regulating expression of SERT protein and mRNA (regulating 5-HT/5-HT3R signaling)．.

[Effect of moxibustion on TLR4/MyD88/NF-κB signaling pathway in colon of diarrhea-predo-minant irritable bowel syndrome rats].

OBJECTIVE: To observe the effect of moxibustion on serum inflammatory factors, Toll-like receptor 4 (TLR4), myeloid differentiation factor 88 (MyD88) and nuclear factor Kappa B (NF-κB) in colon tissue of rats with diarrhea-predominant irritable bowel syndrome (IBS-D)，so as to explore the mechanism of moxibustion in the treatment of IBS-D. METHODS: Healthy male SD rats were randomly divided into blank group, model group and moxibustion group, with 8 rats in each group. The IBS-D model was established by chronic restraint combined with gavage of Senna-leaf solution. The rats of the moxibustion group was treated with moxibustion at "Tianshu"(ST25)and "Shangjuxu"(ST37)for 30 min， once a day for 7 d. After the intervention, the rate of loose stools and the minimum threshold volume of abdominal withdrawal reflex (AWR) induced by colorectal distension were observed. The contents of serum inflammatory factors IL-1ß, TNF-α and IL-6 were detected by ELISA. The pathological changes of rat colon were observed by H.E. staining. The average optical density of TLR4 and NF-κB (p65) in colon tissue was detected by immunohistochemistry. The relative expressions of TLR4, MyD88 and NF-κB (p65) mRNAs in colon tissues were detected by real-time fluorescence quantitative PCR, and the expression levels of TLR4, MyD88 and NF-κB (p65) proteins in colon tissues were detected by Western blot. RESULTS: There was a mild degree of inflammation in colon in rats of the model group. Compared with the blank group, the minimum volume threshold of AWR decreased significantly (P< 0.01), and the rate of loose stools, the contents of IL-1ß, IL-6 and TNF-α in serum as well as the expressions of TLR4, MyD88, NF-κB (p65) mRNAs and protein in colon tissues were significantly increased in the model group (P<0.01). Compared with the model group, the inflammation was alleviated in colonic mucosa, the minimum volume threshold of AWR increased significantly (P<0.01), and rate of loose stools decreased significantly (P<0.01) in the moxibustion group, the contents of IL-1ß, TNF-α and IL-6 in serum and the expression levels of TLR4, MyD88, NF-κB (p65) mRNAs and proteins in colon tissue decreased significantly in the moxibustion group (P<0.01). CONCLUSION: Moxibustion ST25 and ST37 can improve diarrhea symptom and visceral hypersensitivity in IBS-D rats, which may be related with its effects in inhibiting TLR4/MyD88/NF-κB signaling pathway and reducing the expression of inflammatory factors.

[Professor CHU Hao-ran's experience of acupuncture and moxibustion of regulating spleen-stomach and differentiating meridians-collaterals].

Professor CHU Hao-ran successively followed famous doctors of acupuncture and spleen-stomach disease, such as ZHOU Mei-sheng, inherited their academic thoughts and clinical experience, and studied the classics to summarize and propose the clinical academic proposition regulating spleen-stomach, differentiating meridians-collaterals. In clinical practice, professor CHU focuses on individual differences of patients, carefully examines syndrome and refines acupoint selection; he pays attention to regulating spleen-stomach, and actively uses Zusanli (ST 36); he simultaneously uses acupuncture-moxibustion and acupoints with efficacy; he inherits traditional reinforcing and reducing methods, and extends the scope of acupoint diagnosis and treatment, while he emphasizes keeping spirit and treating spirit, and the combination of mind and qi, in order to improve clinical diagnosis and treatment effect.

[Treatment of Vascular Cognitive Impairment by "Huayu Tongluo" Moxibustion].

OBJECTIVE: To observe the therapeutic effect of "Huayu Tongluo"(blood stasis-removing and meridian-collateral-dredging) moxibustion for vascular cognitive impairment(VCI) patients and changes of insulin like growth factor -1(IGF-1) levels in serum after the treatment. METHODS: Sixty patients with VCI were randomly divided into medication (control) and moxibustion groups (n＝30 in each group). Cotton cloth-separated moxibustion was applied to Baihui (GV 20) and Shenting (GV 24), and conventional moxibustion applied to Dazhui (GV 14) and Yongquan (KI 1) for 30 min, once daily, 6 times a week and for 30 days. Patients of the control group were treated by oral administration of Donepezil hydrochloride at the dose of 5 mg/night for 30 days. The core symptoms of traditional Chinese medicine (TCM), mini-mental state examination(MMSE), activity of daily living(ADL) and Montreal cognitive assessment(MoCA) scales were used to assess the therapeutic effect after the treatment. The content of serum IGF-1 was determined by ELISA. RESULTS: Of the two 30 cases in the control and moxibustion groups, 9 and 17 experienced marked improvement, 13 and were effective, 8 and 3 ineffective, with the effective rates being 73.33% and 90.00%, respectively. The effective rate in the moxibustion group was obviously higher than that in the control group (P<0.05). After the treatment, the TCM symptom scores were significantly decreased, and the MMSE, ADL and MoCA scores considerably increased in both groups compared with those of their own individual pre-treatment (P<0.01). The TCM symptom score of the moxibustion group was significantly lower, and the MMSE and ADL scores were obviously higher than those of the control group (P<0.01). The serum IGF-1 content in both groups was significantly increased after the treatment relevant to that of their own individual pre-treatment (P<0.01), and was obviously higher in the moxibustion group than in the control group (P<0.01). No significant difference was found between the two groups in the MoCA score after the treatment (P>0.05)．. CONCLUSION: "Huayu Tongluo" moxibustion has a positive effect for patients with VCI, which may be associated with its effect in up-regulating serum IGF-1 level.

The Genetic Basis of Natural Variation in Kernel Size and Related Traits Using a Four-Way Cross Population in Maize.

Kernel size is an important component of grain yield in maize breeding programs. To extend the understanding on the genetic basis of kernel size traits (i.e., kernel length, kernel width and kernel thickness), we developed a set of four-way cross mapping population derived from four maize inbred lines with varied kernel sizes. In the present study, we investigated the genetic basis of natural variation in seed size and other components of maize yield (e.g., hundred kernel weight, number of rows per ear, number of kernels per row). In total, ten QTL affecting kernel size were identified, three of which (two for kernel length and one for kernel width) had stable expression in other components of maize yield. The possible genetic mechanism behind the trade-off of kernel size and yield components was discussed.

Genomic Dissection of Leaf Angle in Maize (Zea mays L.) Using a Four-Way Cross Mapping Population.

Increasing grain yield by the selection for optimal plant architecture has been the key focus in modern maize breeding. As a result, leaf angle, an important determinant of plant architecture, has been significantly improved to adapt to the ever-increasing plant density in maize production over the past several decades. To extend our understanding on the genetic mechanisms of leaf angle in maize, we developed the first four-way cross mapping population, consisting of 277 lines derived from four maize inbred lines with varied leaf angles. The four-way cross mapping population together with the four parental lines were evaluated for leaf angle in two environments. In this study, we reported linkage maps built in the population and quantitative trait loci (QTL) on leaf angle detected by inclusive composite interval mapping (ICIM). ICIM applies a two-step strategy to effectively separate the cofactor selection from the interval mapping, which controls the background additive and dominant effects at the same time. A total of 14 leaf angle QTL were identified, four of which were further validated in near-isogenic lines (NILs). Seven of the 14 leaf angle QTL were found to overlap with the published leaf angle QTL or genes, and the remaining QTL were unique to the four-way population. This study represents the first example of QTL mapping using a four-way cross population in maize, and demonstrates that the use of specially designed four-way cross is effective in uncovering the basis of complex and polygenetic trait like leaf angle in maize.

[Effects of electroacupuncture on learning-memory ability and expression of hippocampal vascular endothelial growth factor (VEGF), VEGF receptor 1 and 2 genes in vascular cognitive impairment rats].

OBJECTIVE: To observe the effect of electroacupuncture (EA) of "Dazhui" (GV 14), "Baihui" (GV 20), etc. on learning-memory ability and expression of vascular endothelial growth factor (VEGF) mRNA, VEGF receptor 1 (VEGFR-1/Flt-1) mRNA, and VEGFR-2 (Flk-1) mRNA in the hippocampus in vascular cognitive impairment (VCI) rats so as to reveal its mechanism underlying improvement of VCI. METHODS: A total of 60 Wistar rats were randomly divided into sham operation, VCI model, EA and medication groups (n=12 in each group). The VCI model was established by occlusion of the bilateral vertebral arteries and bilateral cervical arteries. EA (2 Hz/20 Hz) was applied to "Baihui" (GV 20), "Dazhui" (GV 14), "Shuigou" (GV 26) and "Shenting" (GV 24) for 20 min, once daily for 20 days. Rats of the medication group were treated by intragastric perfusion of Aniracetam capsules (0.0625 g/kg),once daily for 20 days. The rats' learning-memory ability was detected by step-down test. The expression levels of VEGF mRNA, Flt-1 mRNA and Flk-1 mRNA in the hippocampus were detected by RT-PCR, and the neurological deficit scores were assessed by Zea Longa (0-4 scaling) method. RESULTS: Compared with the sham operation group, rats of the model group showed a significant increase in reaction time and error number and decrease of escape latency (reduction of learning-memory ability), and increase in neurological deficit score, and in expression levels of hippocampal VEGF mRNA, Flt-1 mRNA and Flk-1 mRNA (all P<0.01). After EA treatment, in comparison with the model group, the learning-memory ability and hippocampal VEGF mRNA, Flt-1 mRNA and Flk-1 mRNA were apparently increased, neurological deficit score were markedly decreased in the EA group (all P<0.01). The effects of EA treatment was obviously superior to those of medication in raising learning-memory ability and up-regulating hippocampal VEGF mRNA and Flt-1 mRNA expression levels, and in reducing neurological deficit score (all P<0.05). CONCLUSION: EA intervention can apparently up-regulate hippocampal VEGF mRNA, Flt-1 mRNA and Flk-1 mRNA expression in VCI rats, which may contribute to its effect in improving learning-memory ability, possibly by promoting neovasculization.