Population Of Northeast China Research Articles

Adaptation of Diverse Maize Germplasm to Spring Season Conditions in Northeast China

Northeast China (NEC) is a major spring maize (Zea mays L.) growing belt, and the outputs substantially influence national grain production. However, the maize grain yield per unit area has little changes in recent years, partially due to the lack of elite germplasm resources and innovation. Therefore, this study aimed to determine the performance of diverse populations in NEC to propose appropriate strategies for the utilization of elite germplasm to broaden the genetic base of Chinese germplasm. Fifteen diverse maize populations from the International Maize and Wheat Improvement Center (CIMMYT) and the U.S. were crossed to two local tester lines, representing Chinese heterotic groups Reid and Lancaster, for evaluating the combining ability and heterosis in three locations (Gongzhuling, Jilin Province, and Harbin and Suihua, Heilongjiang Province) in NEC over two years. The U.S. (BS13(S)C7 and BS31) and Chinese (Ji Syn A) populations exhibited more favorable alleles for high yield potential in all locations tested. Furthermore, the PH6WC × BS31 and PH6WC × Ji Syn A crosses had higher grain yields, and an appropriate number of days to silking, ear height, and resistance to lodging at Gongzhuling and Harbin in NEC. The best strategies for utilizing these diverse germplasms may be to develop new inbred lines from the existing elite populations or improve the grain yield and resistance to lodging of the elite line PH4CV for broadening the genetic base of the Chinese group Lancaster in NEC.

Characteristics of wild hazelnut populations in Northeast China and selection of superior provenances.

China possesses a copious and geographically diverse reservoir of hazel (Corylus spp.) resources, albeit scholarly endeavors focusing on the selection and domestication of indigenous wild hazelnut strains remain scant. To develop and utilize high-quality wild hazelnut resources, this study selected eight populations of wild hazelnuts from seven different provenances in Heilongjiang Province, China. Natural hybrid seeds of eight populations were sown in the Chohai Forest Farm in Longjiang County, Heilongjiang Province, in 2018. In April 2020, two-year-old seedlings were used to establish a provenance trial forest, thereby initiating the provenance trial. Growth parameters were measured using electronic calipers, and pollen characteristics were observed under an electron microscope. The trials meticulously explored the trees' flowering biology, growth parameters, and the economic attributes of the produced nuts. Principal component analysis was employed to comprehensively assess differences among the wild hazelnut populations from various provenances, aiming to identify superior wild hazelnut provenances. The results unveiled significant geographical variations among the tested provenances across several facets: the flowering period of male blossoms extended from April 2nd to April 19th, while female flowering occurred within the timeframe of April 2nd to April 22nd. Moreover, pollen grain morphology demonstrated variability, with the polar axis ranging from 14.02 to 17.09 micrometers, the equatorial axis spanning 16.02 to 18.75 micrometers, and the ratio of polar to equatorial axes fluctuating between 0.88 and 0.92. Through correlation analyses, nut length emerged as a pivotal determinant significantly influencing both kernel weight and the hundred-grain weight. A principal component analysis (PCA) further consolidated these findings, selecting the Nehe-originated variegated Corylus heterophylla as the superior provenance based on a comprehensive evaluation of its combined traits. This study constitutes a seminal contribution to the hazelnut breeding endeavor in China, establishing a robust foundation for informed cultivation strategies geared towards optimizing both the yield and the quality of hazelnut resources, thereby advancing the understanding and exploitation of China's wild hazelnut biodiversity.

Morphological and molecular data demonstrate the existence of Betula fruticosa and B. middendorffii and the absence of B. ovalifolia in northeastern China

Abstract Shrub birches are important components of massive wetlands in Northeast China, although much of these habitats have been lost over the past two decades. However, the taxonomy of shrub birches has been ambiguous owing to their morphological variation. In this study, we incorporated morphological and molecular data to address the taxonomic challenges associated with shrub birches. We characterized the morphological variation in the leaves, seeds, and bracts of 11 shrub birch populations in Northeast China and a population of Betula ovalifolia in northern Japan. We genotyped birch individuals from Northeast China at 15 microsatellite loci as well as a subset of individuals, using restriction site-associated DNA sequencing (RAD-seq). The populations in Northeast China consisted of B. fruticosa and B. middendorffii. These two species and B. ovalifolia differ in the width of their seed wings and the angle between the side lobes of their bracts, despite substantial intraspecific variation. Our genetic data revealed two distinct clusters, corresponding to B. fruticosa and B. middendorffii. Ploidy level assessment via RAD-seq revealed that B. fruticosa is diploid and B. middendorffii is tetraploid. Phylogenetic analysis revealed that B. fruticosa formed a sister clade to diploid B. humilis, and B. middendorffii formed a clade with diploid B. nana. Our results indicate the existence of B. fruticosa and B. middendorffii and the probable absence of B. ovalifolia in the northern Daxing’an Range, as all the tetraploid individuals sampled there represented B. middendorffii. In addition, our results suggest that B. humilis and B. nana may have served as diploid parents of the tetraploid species B. ovalifolia and B. middendorffii, respectively.

Molecular characterization of avian metapneumovirus subtype C associated with hydrosalpinx fluid and egg drop syndrome in Jinding ducks.

A disease called "hydrosalpinx fluid and egg drop syndrome" (HFEDS) was observed in four flocks of Jinding ducks (Anas platyrhynchos domesticus) in Northeast China during the years 2022 to 2023. Here, we investigated the possible involvement of avian metapneumovirus (AMPV) infection. Full-length genome sequencing and sequence analysis of two AMPV strains showed that they belong to Eurasian lineage of AMPV subtype C. Based on surface glycoprotein (G) sequence comparisons, the Eurasian lineage can be divided into two sublineages (E1 and E2), and sublineage E2 is circulating in Jinding duck populations in Northeast China.

The history of migration in Northeast China in the XX-XXI centuries.

The subject of this article is the analysis of internal migration processes in Northeast China from the 20th century to the beginning of the 21st century. Special attention is paid to the dynamics of migration flows and their significant impact on the demographic situation of the region. The author examines the specific features of internal migration in different provinces: Liaoning with its subprovincial cities demonstrates a net influx of population, while Jilin and Heilongjiang provinces are characterized by a significant net outflow of population. The author explores the causes of these migration processes and their direct impact on the demographic development of the Northeast region of China. This allows us to better understand the significant changes taking place in underdeveloped regions of China and identify the main factors affecting internal migration. The study used statistical analysis of data on migration flows, demographic studies, as well as comparative analysis of data from various provinces of Northeast China to identify key factors affecting internal migration. The scientific novelty of this study lies in a detailed analysis of internal migration processes and their impact on the demographic situation in Northeast China, which has not been studied in depth before. The study revealed that the region is facing serious problems such as resource depletion and insufficient economic growth, which leads to negative population growth. Negative growth is characterized by significant regional imbalance: most prefectural-level cities, with the exception of Shenyang, Dalian and Changchun, show negative population growth. Especially high rates are observed in Suihua and Daxinganlin in Heilongjiang Province. The population of the border areas has decreased by almost a fifth. The findings of the study confirm that the population in Northeast China continues to decline, accompanied by a marked decrease in the birth rate. This steady decline requires effective measures to slow it down. The outflow of population from the northeast is increasing, while the departing population is usually younger and more educated, which leads to an acceleration of the aging process and loss of human capital. The main features of the region's demographic trends are net population outflow and migration, which makes it an excellent example for studying demographic changes in underdeveloped regions.

Nomogram for predicting risk of mild renal dysfunction among general residents from rural Northeast China.

Cumulative evidence confirms that mild renal dysfunction (MRD) is correlated with many cardiovascular risk factors and increases cardiovascular morbidity and mortality. The purpose of this study was to establish an effective nomogram for predicting the risk of MRD in the rural population of Northeast China. We analyzed the reports of 4944 subjects from the Northeast China Rural Cardiovascular Health Study (NCRCHS). All the participants completed the questionnaires, anthropometric measurements, and blood tests during the baseline study (2012-2013) and the follow-up study during 2015-2017 (an average of 4.6 years). The Chronic Kidney Disease Epidemiology (CKD-EPI) equation was used to calculate the estimated glomerular filtration rate (eGFR), and eGFR in the range of 60-90 mL/min/1.73m2 was defined as MRD. The study revealed that a total of 889 subjects (18.0%) had MRD. Multivariate logistic analysis showed that annual income, abdominal obesity, hypertension, hyperglycemia, and frequent tea consumption were the independent risk factors (P < 0.05) for MRD. Thereafter, a nomogram with an area under the receiver operating characteristic curve (AUC) of 0.705 was constructed to accurately predict MRD. The calibration plot also showed an excellent consistency between the probability of prediction and observation. We constructed a nomogram based on epidemiological data, which could provide an individual prediction of MRD with good accuracy.

Analysis of the genetic structure of the introduced clearhead icefish (Protosalanx chinensis) populations in northern China.

When species are introduced to a new environment, they can quickly adapt to the environment and may differ from the indigenous species. The indigenous population of Protosalanx chinensis has a high level of genetic diversity, but it is unclear on the genetic diversity of the introduced populations in northeast China, which supports the major production of P. chinensis in the world. A total of 556 individuals of P. chinensis were collected during 2016-2021, from Lianhuan Lake (LHL), Xingkai Lake (XK), and Shuifeng Reservoir (SF), and one population was collected from the indigenous Taihu Lake (TH). Overall, 36 haplotypes were detected, and the genetic differences in P. chinensis populations within and between river basins were investigated. The nucleotide diversity (π) of the populations ranged from 0.0005 to 0.0032, and the haplotype diversity (Hd) ranged from 0.455 to 0.890, with the highest genetic diversity in the TH population, followed by the SF population, and lower genetic diversity in the XK and LHL populations. The analysis of the genetic differentiation index (Fst) and the genetic distance between populations showed that there was significant genetic differentiation between the TH population and the other populations. More sampling points have been set up in LHL for further analysis; the Dalong Lake (DL) and the Xiaolong Lake (XL) populations were far from the other populations within the LHL population. In this study, we didn't find a correlation between population size, stability, and genetic diversity, and the ecological measures of management should be decisive to the population dynamics. These results provide a basis for the rational utilization and effective management of P. chinensis.

Common carotid artery diameter and the risk of cardiovascular disease mortality: a prospective cohort study in northeast China.

The association between the common carotid artery (CCA) diameter and cardiovascular disease (CVD) is recognized, but the precise nature of this link remains elusive. This study aimed to investigate the potential relationship between CCA diameter and the risk of CVD mortality in a large population in northeast China. The current study included 5668 participants (mean age 58.9 ± 10.1years) from a population-based study conducted in rural areas of northeast China between September 2017 and May 2018. Information on death was collected from baseline until July 31, 2022. The CCA inter-adventitial diameter was measured using ultrasound. Cox proportional-hazard models were employed to explore the relationship between the common carotid artery diameter and cardiovascular mortality. At baseline, the mean CCA diameter (mm) of subjects was 7.30 ± 0.99 and increased significantly with age, ranging from 6.65 ± 0.71 among people 40-49years to 7.99 ± 1.04 among people ≥ 80years. CCA diameter was significantly larger in males compared to females (7.51 ± 1.03 versus vs. 7.16 ± 0.94; P < 0.001). A total of 185 participants died of CVD during a median follow-up of 4.48years. CCA diameters were divided into quartiles, and the highest quartile of carotid diameter (≥ 8.06mm) had a 2.29 (95% confidence interval [CI]: 1.24, 4.22) times higher risk of CVD mortality than the lowest quartile (≤ 6.65mm) (P < 0.01) in the fully adjusted model. Each increase in the diameter of the common carotid artery (per SD) raised the risk of cardiovascular death by 36% (hazard ratio [HR]: 1.36; 95% CI: 1.18, 1.57). The subgroup analysis results demonstrated that a per SD increase was associated with a 42% increased risk of CVD mortality in participants aged ≥ 64years in the fully adjusted model (HR: 1.42; 95%CI: 1.21, 1.66). Our study indicates the possible incremental value of CCA diameter in optimizing the risk stratification of cardiovascular disease and provides essential insights into reducing the burden of cardiovascular disease.

Estimation of the Population Dynamics of Taxus cuspidata by Using a Static Life Table for Its Conservation

Taxus cuspidata is a rare and endangered plant species with an extremely small population which is endemic to China. This study focused on the natural T. cuspidata population in Jilin Province in China. Conventional population ecology survey methods were used to describe its population structure characteristics. Then, we chose diameter structure instead of temporal structure to establish a static population life table, draw a population survival curve, and quantify the future development trend by using population dynamic analysis and time sequence prediction. The results showed that: (1) the static life table suggested that the population of T. cuspidata was stable overall. The population survival curve tended to be Deevey Ⅱ, with a high early seedling mortality, and the later population growth tended to be stable; (2) the survival curve suggested that the population initially experienced higher mortality rates in the early stage. However, as time progressed and the population aged, the mortality rates decreased, resulting in a more stable population in the middle and late stages; (3) The diameter class structure of T. cuspidata was stable overall, and the dynamic indices showed that the population was fluctuating. The population was influenced by external disturbances and showed some resistance to human disturbance; (4) time sequence prediction analysis showed that the mortality rate of young individuals was high, natural renewal could be maintained, and the population size would remain at a certain amount in the future. The result shows that the Jilin region is a highly suitable area for the growth of Taxus cuspidata’s population in Northeast China. We recommend in situ conservation of remaining wild populations, relocation of germplasm resources, and reduction of human activities; these actions will be beneficial to Taxus cuspidata’s long-term survival.

Genetic analysis of 42 Y-STR loci in Han and Manchu populations from the three northeastern provinces in China

BackgroundY-STR polymorphisms are useful in tracing genealogy and understanding human origins and migration history. This study aimed to fill a knowledge gap in the genetic diversity, structure, and haplogroup distribution of the Han and Manchu populations from the three northeastern provinces in China (Liaoning, Jilin, and Heilongjiang).MethodsA total of 1,048 blood samples were collected from unrelated males residing in Dalian. Genotyping was performed using the AGCU Y37 + 5 Amplification Kit, and the genotype data were analyzed to determine allele and haplotype frequencies, genetic and haplotype diversity, discrimination capacity, and haplotype match probability. Population pairwise genetic distances (Fst) were calculated to compare the genetic relationships among Han and Manchu populations from Northeast China and other 23 populations using 27 Yfiler Plus loci set. Multi-dimensional scaling and phylogenetic analysis were employed to visualize the genetic relationships among the 27 populations. Moreover, haplogroups were predicted based on 27 Yfiler Plus loci set.ResultsThe Han populations from Northeast China exhibited genetic affinities with both Han populations from the Central Plain and the Sichuan Qiang population, despite considerable geographical distances. Conversely, the Manchu population displayed a relatively large genetic distance from other populations. The haplogroup analysis revealed the prevalence of haplogroups E1b1b, O1b, O2, and Q in the studied populations, with variations observed among different ethnic groups.ConclusionThe study contributes to our understanding of genetic diversity and history of the Han and Manchu populations in Northeast China, the genetic relationships between populations, and the intricate processes of migration, intermarriage, and cultural integration that have shaped the region’s genetic landscape.

Yield and cost of government-organized colorectal cancer screening in young high-risk population in Northeast China

Guidelines for colorectal cancer (CRC) screening recommend screening at age 40 for high-risk population in China. However, the yield and cost of CRC screening in younger population are lacking. This analysis aimed to evaluate the yield and cost of CRC screening in high-risk 40- to 54-year-olds. Individuals aged 40–54 years who were determined to have a high risk of CRC were recruited from December 2012 to December 2019. We calculated odds ratios (OR) and 95% confidence intervals (CI) for the detection rate of colorectal lesions among the three age groups and further calculated number of colonoscopies needed to screen (NNS) to detect one advanced lesion and cost of each group. The detection rates of advanced colorectal neoplasm in men aged 45–49 years (OR = 2.00, 95% CI: 0.93–4.30) and 50–54 years (OR = 2.19, 95% CI: 1.04–4.62) were higher than that aged 40–44 years. The detection rates of colorectal adenoma in women aged 50–54 years was higher than that aged 40–44 years (OR = 1.64, 95% CI: 1.23–2.19). Among the male screening population, NNS and cost to detect one advanced lesion in participants aged 45–49 years were similar to that aged 50–54 years, saving approximately half endoscopic resources and financial expenses compared with screening that aged 40–44 years. From the perspective of screening results and costs, it might be beneficial to delay the starting age of screening by gender. This study may provide reference for optimizing CRC screening strategies.

Clinicopathologic Features and Prognosis of Melanoma in Northeast China: A Region-Based Cohort Study of 229 Consecutive Cases

Melanoma has been reported in many parts of East Asia. However, there are no reports on the epidemiology of melanoma in Northeast China. In this study, we collected demographic, clinicopathologic, and treatment data of patients with melanoma treated at the First Hospital of Jilin University (Changchun, China). A total of 229 consecutive nonselective cases were analyzed for the incidence and clinicopathologic characteristics of melanoma. The median overall survival was 53.5 months. The 1-year, 3-year, and 5-year survival rates were 86.3, 66.4, and 44.8%, respectively. The median disease-free survival was 33.1 months, and the 1-year, 3-year, and 5-year disease-free survival rates were 75.0, 48.5, and 35.8%, respectively. Multivariate analysis showed that disease stage, Eastern Cooperative Oncology Group score, and lactic dehydrogenase were independent prognostic factors of overall survival. Pathologic subtype and stage were independent prognostic factors of disease-free survival. Furthermore, vascular invasion was a prognostic factor for overall survival in acral melanoma and a prognostic factor for disease-free survival in cutaneous melanoma. Compared with the Caucasian population, the population of Northeast China showed significant differences in disease location, pathologic subtype, gene status, and survival prognosis. In summary, our study showed that vascular invasion might be a prognostic factor in patients with acral and cutaneous melanoma.

Evaluation Soybean Cultivars for Reaction to Heterodera glycines Populations HG Types 7 and 1.3.4.7 in Northeast China.

Soybean cyst nematode Heterodera glycines (SCN) is a major threat to global soybean production. Effective management of this disease is dependent on the development of resistant cultivars. Two SCN HG Types, 7 and 1.3.4.7. were previously identified as prevalent H. glycines populations in Northeast China. In order to evaluate soybean cultivars resistant to local SCN populations, 110 domestic commercial soybeans from different regions of Northeast China were assessed in the greenhouse to determine their potential as novel sources of resistance. The results suggested that cultivars responded differently to the two HG types. Of the 110 soybean cultivars evaluated, 24 accessions were classified as resistant or moderately resistant to HG Type 7, and five cultivars were classified as resistant or moderately resistant to HG Type 1.3.4.7. Among the tested cultivars, Kangxian 12 and Qingdou 13 had resistance response to both HG types 7 and 1.3.4.7. Thus, these broad-based SCN cultivars will be the valuable materials in the SCN resistance breeding program.

Genetic diversity analysis and fingerprint construction of Korean pine (Pinus koraiensis) clonal seed orchard.

Korean pine is a native tree species in Northeast China. In order to meet the needs of germplasm resource evaluation and molecular marker-assisted breeding of Korean pine, we collected Korean pine clones from 7 populations in Northeast China, analyzed the genetic diversity and genetic structure by SSR molecular marker technology and clustered them to revealed the inter- and intrapopulation differentiation characteristics of each clone. The fingerprint profiles of 161 Korean pine clones were also constructed. 77 alleles were detected for 11 markers, and 18 genotypes were identified on average for each marker. The PIC of the different markers ranged from 0.155-0.855, and the combination of PI and PIsibs for the 11 markers was 3.1 × 10-8 and 1.14 × 10-3, respectively. MANOVA showed that genetic variation existed mainly within populations, accounting for 98% of the total variation. The level of genetic differentiation among populations was low, with an average Nm between populations of 11.036. Genetic diversity is lower in the Lushuihe population and higher in the Tieli population. The 161 Korean pine clones were divided into 4 or 7 populations, and the 7 populations were not clearly distinguished from each other, with only the Lushuihe population showing partial differentiation. There is no significant correlation between the genetic distance of Korean pine populations and the geographical distance of their superior tree sources. This result can provide recommendations for future Korean pine breeding programs. The combination of 11 markers could completely distinguish 161 clones and establish the fingerprint. Genetic diversity of Korean pine clones from the 7 populations was abundant, and the genetic distances of individuals and populations were evenly dispersed. The fingerprint map can be used for the identification of Korean pine clones.

Interventricular Septum Thickness for the Prediction of Coronary Heart Disease and Myocardial Infarction in Hypertension Population: A Prospective Study.

The aim of the present study was to evaluate the prognostic value of interventricular septum thickness (IVSd) on the incidence of cardiovascular diseases. Based on the general population in Northeast China, 10,349 participants were successfully followed up for echocardiography over a median follow-up time of 4.66 years, among which 4801 were hypertensive. Coronary heart disease (CHD) and myocardial infarction (MI) incidence were followed up. Cox proportional hazards models were used to estimate the association of the baseline IVSd with adverse outcomes. IVS hypertrophy increased incident rates of CHD and MI compared with normal IVSd in the overall population and in the female sex-stratification group. In males, IVS hypertrophy had parallel increase rates of CHD (all p &lt; 0.05). Kaplan-Meier analysis showed that IVS hypertrophy could predict CHD and MI incidence and CHD-free and MI-free survival. Multivariable Cox analysis revealed that IVS hypertrophy was correlated with CHD incidence (HR = 1.155, 95% CI = 1.155-2.861, p = 0.01) and MI incidence (HR = 2.410, 95% CI = 1.303-4.458, p = 0.005). In women, IVS hypertrophy was independently associated with CHD and MI incidence (all p &lt; 0.05). Our prospective cohort study illustrated that IVS hypertrophy detected by echocardiography has a prognostic significance for CHD and MI. Therefore, the early detection of IVSd should be conducted to avoid adverse outcomes in further clinical practice.

Mapping the habitat for the moose population in Northeast China by combining remote sensing products and random forests

Many wildlife species face the risks of habitat loss, habitat fragmentation or local extinction in response to climate change and anthropogenic disturbance. Moose (Alces alces) in Northeast China is on the southernmost edge of the geographical range of Eurasian moose, the distribution of this population is retreating, and population number has been declining for the last several decades. However, little is known about its habitat suitability over a large spatial scale, which hinders further effective conservation of the moose in China. It is critical to explore the moose-habitat relationships and habitat suitability to understand moose habitat requirements, potential land use impacts, and effective management. In this paper, we combined remote sensing-derived predictors and machine learning methods (down-sampling random forests) to explore the moose-habitat associations and map moose habitat suitability. Results showed that our model performed well to excellently in terms of three evaluation metrics (AUCROC, AUCPR, CBI), which indicates the advantages of the combination of remote sensing and machine learning methods in predicting moose habitat. We identified the main factors driving moose distribution in Northeast China are the human footprint index, the mean monthly maximum temperature of the late spring, the percentage of coniferous forest, the minimum dynamic habitat index, the minimum temperature of the coldest month, and the distance from town. Moose responds to these variables nonlinearly. Generally, variables related to human disturbance and heat stress are the main drivers of moose occurrence and are negatively associated with moose occurrence probability. High suitability areas are mainly distributed in eastern and northern Greater Khingan Mountains. Highly suitable habitat covers only a small proportion of the study area. We identified 67,400 km2 of suitable habitat covering 13.6% of the study area. Our study can provide critical information for decision-makers when designing conservation and management strategies for the moose in China and other regions of the world with similar conditions.

Spatiotemporal Evolution of County-Level Land Use Structure in the Context of Urban Shrinkage: Evidence from Northeast China

Shrinking cities are a class of cities that show different trajectories in the urbanization process. Although many studies have examined shrinking cities from multi-dimensional perspectives, the spatiotemporal evolution of land use structure is still poorly understood. This study constructed an analysis framework for spatiotemporal evolution characteristics of land use structure over two 10-year periods based on 334 county-level administrative units in the context of northeast China, a region undergoing substantial population loss and urban shrinkage. This study analyses quantitatively measured population loss and land use conversion and investigated the rationality of the expansion mode of newly added construction land in research units. The results demonstrated that, first, the total population in northeast China continued to decline, but the total construction area continued to grow, and the various types of construction land in most shrinking units did not decline with the loss of population. Second, 67.09% of new construction land came from cropland, and compared with 2000–2010, the growth of new construction land in 2010–2020 slowed down. Third, during the study period, more than half of the expansion area for newly added construction land came from sprawling expansion, and areas in a state of shrinking were no exception.

Evaluation of Risk Factors for Chronic Obstructive Pulmonary Disease in the Middle-Aged and Elderly Rural Population of Northeast China Using Logistic Regression and Principal Component Analysis.

PurposeTo investigate the environmental, immune, and inflammatory factors associated with chronic obstructive pulmonary disease (COPD) in middle-aged and older Chinese individuals.Patients and MethodsA community-based case–control study was conducted among 471 patients with COPD and 485 controls. The information on COPD of the participants was collected through face-to-face interviews, and serum samples were measured at the laboratory. The main risk factors for COPD were analyzed using principal component analysis (PCA) and logistic regression.ResultsNine hundred and fifty-six respondents were included in the analysis. The results of the PCA-logistic regression analysis showed significant differences in the environmental factors, medical history, and serum C-reactive protein (CRP) levels between patients and controls. COPD was markedly more usual in those with smoking index >200 (OR, 1.42; 95% CI, 1.28–1.57); exposure to outdoor straw burning (OR, 1.64; 95% CI, 1.47–1.83); use of coal, wood, and straw indoors (OR, 2.31; 95% CI, 1.92–2.78); history of respiratory disease and coronary heart disease (OR, 3.58; 95% CI, 3.12–4.10), congestive heart failure (OR, 1.23; 95% CI, 1.09–1.38), and cerebrovascular disease (OR, 1.15; 95% CI,1.02–1.31); and higher serum level of CRP (OR, 1.20; 95% CI, 1.11–1.30). Compared to the logistic regression analysis, PCA logistic regression analysis identified more important risk factors for COPD.ConclusionPCA-logistic regression analysis was first utilized to explore the influencing factors among rural residents in Northeast China Environmental aged 40 years and above, it was found that environmental factors, medical history, and serum CRP levels mainly affected the prevalence of COPD.

"Study on Gene Polymorphism of Antihypertensive Drugs in Manzu Race Population in Northeast China"

"Study on Gene Polymorphism of Antihypertensive Drugs in Manzu Race Population in Northeast China"

Genetic Diversity of Juglans mandshurica Populations in Northeast China Based on SSR Markers.

Juglans mandshurica is a native tree species in Northeast China. Due to habitat destruction and human disturbance, its population size has sharply decreased. Currently, information on molecular markers of J. mandshurica is limited and cannot meet the needs of germplasm resource evaluation and molecular marker-assisted breeding of J. mandshurica. Based on transcriptomic data from three tissues (leaves, bark, and fruit pericarp), we developed expressed sequence tag-simple sequence repeats (EST-SSRs) for J. mandshurica, and 15 polymorphic EST-SSR primers were initially selected. The average number of alleles (Na), expected heterozygosity (He), and the polymorphic information content (PIC) at different loci were 18.27, 0.670, and 0.797, respectively. Population genetic diversity analysis revealed that the average Na, He, and Shannon information indices (I) for 15 J. mandshurica populations were 6.993, 0.670, and 1.455, respectively. Among them, population Hunchun exhibited the highest genetic diversity (Na = 7.933, He = 0.723, and I = 1.617), while population Heihe exhibited the lowest genetic diversity (Na = 4.200, He = 0.605, and I = 1.158). STRUCTURE analysis, neighbor-joining method cluster analysis, and principal coordinate analysis showed that the 343 individuals of J. mandshurica from 15 populations were clustered into three categories. Category 1 (green) had 147 individuals from eight populations in Qingyuan, Caohekou, Jian, Ningan, Yongji, Baishishan, Helong, and Maoershan; category 2 (blue) had 81 individuals from three populations in Hulin, Boli, and Sanchazi; and category 3 (red) had 115 individuals from four populations in Heihe, Hunchun, Fangzheng, and Liangshui. Analysis of molecular variance (AMOVA) showed that genetic variations among and within individuals accounted for 16.22% and 21.10% of the total genetic variation, respectively, indicating that genetic variations within populations were greater than genetic variations among populations. The average genetic differentiation coefficient (Fst) and gene flow (Nm) between different populations were 0.109 and 4.063, respectively, implying moderate levels of genetic differentiation and gene flow. Based on the genetic diversity characteristics of different populations, we proposed various genetic conservation strategies for J. mandshurica.