Emergence and circulation of enterovirus B species in infants in southern China: A multicenter retrospective analysis

BACKGROUND

Enteroviruses (EV) are common and can cause severe diseases, particularly in young children. However, the information of EV infection in infants in China is limited due to the vast population size and extensive geographical area of the country. Here, we conducted a retrospective multicenter analysis of available EV data to assess the current epidemiological situation in the infant population in southern China.

METHODS

The study enrolled infants with suspected EV infection from 34 hospitals across 12 cities in southern China between 2019 to 2022, and the confirmation of EV was done using RT-PCR and VP1 gene sequencing.

RESULTS

Out of 1221 infants enrolled, 330 (27.03%) were confirmed as EV-infected. Of these, 260 (78.79%) were newborns aged 0-28 days. The EV belonged to three species: EV-B (80.61%), EV-A (11.82%), and human rhinovirus (7.58%). Newborns were more susceptible to EV-B than older infants (p < 0.001). Within EV-B, we identified 15 types, with coxsackievirus (CV) B3 (20.91%), echovirus (E) 11 (19.70%), and E18 (16.97%) being the most common. The predominant EV types changed across different years. EV infection in infants followed a seasonal pattern, with a higher incidence from May to August. Furthermore, perinatal mother-to-child EV transmission in 12 mother-newborn pairs were observed.

CONCLUSION

Our study is the first to demonstrate the emergence and widespread circulation of EV-B species, mainly CVB3, E11, and E18, in southern China, primarily affecting young infants. This research provides valuable insights for future epidemic assessment, prediction, as well as the elimination of mother-to-child transmission.

Divergence of the freshwater sleeper, Neodontobutishainanensis (Chen, 1985) (Teleostei, Odontobutidae), in the Pearl River basin and on Hainan Island of southern China

Study of divergence of freshwater fish populations between island and adjacent mainland areas can shed light on the phylogeographical relationships of these regions. Neodontobutishainanensis is a freshwater fish species restricted to Hainan Island and in Guangdong and Guangxi provinces in the southern mainland China. We examine the phylogenetic relationship and population structure of N.hainanensis based on 3,176 nuclear loci using a gene-capture method. STRUCTURE analysis and principal coordinate analyses (PCA) indicate that populations from Guangdong, Guangxi and Hainan are each distinct, except that some individuals of the Guangdong population share minor genetic components with individuals of the Guangxi population. In the concatenated gene tree, the Hainan population is grouped with the Guangdong population, but the coalescent tree groups the Hainan population as the sister to the Guangxi population. Finally, coalescent simulations confirmed the divergence pattern supported by the coalescent tree and revealed a one-way introgression from the Guangxi population to the Guangdong population, which can explain the discordant results supported by the concatenated and coalescent phylogenetic analyses. Due to recent decline of N.hainanensis populations and the genetic patterns in this species, as revealed in this study, the populations in the three areas should be treated as separate conservation units.

A new species of freshwater snail of Fenouilia (Gastropoda, Pomatiopsidae) from northern Guangxi, China, based on morphological and DNA evidence

A new species of pomatiopsid freshwater snail, Fenouiliaundata Chen & He, sp. nov., is described from Guangxi, China, based on morphological and molecular evidence. The new species can be distinguished from its congeners by the following combination of characters: shell with low, prosocline, rounded axial ribs and fine spiral striae, broader than high; aperture broader than shell height; radula with lateral teeth have only two or three faint, wavy ridges on inner side. A molecular analysis of partial mitochondrial COI and 16S DNA sequences supports the systematic position of the new taxon.

Two new ant species of the genus Leptogenys (Hymenoptera, Formicidae) from Hainan, China, with a key to the known Chinese species

Two new species of ponerine ants from Hainan Province, China, Leptogenyshainanensissp. nov. and L.zhouisp. nov., are delineated and depicted based on the worker caste. Leptogenyshainanensissp. nov. belongs to the L.leleji species group, with mandibles elongate, slender and curved, lacking a distinct masticatory margin. On the other hand, L.zhouisp. nov. belongs to the L.crassicornis species group, distinguished by its square head, smooth body, mandibles with a dentate masticatory margin, and short antennae. A key to workers for the known species of Leptogenys in China are provided and a map is provided for the newly described species.

Prevalence and phylogenetic analysis of Gyrovirus galga 1 in southern China from 2020 to 2022

Since 2011, the Gyrovirus galga 1 (GyVg1, previously recognized as avian gyrovirus 2) strain has extensively been detected worldwide. However, because there are no up-to-date reports of examining the distribution of GyVg1 in flocks in southern China, the epidemiology of this virus is unknown. To investigate the prevalence and genetic evolution of GyVg1, a total of 2,077 field samples collected from 113 chicken farms in 6 provinces in southern China during 2020 to 2022 were tested. Among them, 315 samples (315/2,077, 15.17%) were positive for GyVg1 by PCR. The positive rate of GyVg1 detection between different regions of southern China ranged from 11.69% (Guangdong) to 22.46% (Yunnan). The correlation between GyVg1 prevalence and sample source groups was analyzed, the results showing that the highest seroprevalence of GyVg1 was observed in visceral tissues (27.34%, 187/684), significantly higher (P < 0.05) than that of feather shafts (17.22%, 31/180), serums (8.85%, 78/881), and fecal (5.72%, 19/332). Additionally, the complete genomes of 10 GyVg1 strains were sequenced and analyzed, which showed nucleotide identities of 96.2 to 99.9%, 97.0 to 100.0%, 95.2 to 100.0%, and 95.7 to 99.8% in the complete genome, ORF1, ORF2, and ORF3, respectively, and 94.4 to 100.0%, 91.3 to 100.0%, and 98.7 to 100.0% amino acid similarity in the VP2, VP3, and VP1 proteins, respectively. Phylogenetic analysis of the whole genome showed that 10 GyVg1 strains belong to genotype I, and one strain belongs to genotype III. Sequence analysis showed several amino acid substitutions in both the VP1, VP2, and VP3 proteins. Our results enhance the understanding of the molecular characterization of GyVg1 infection in southern China. In conclusion, this study reveals the high prevalence and high genetic differentiation of GyVg1 in Chinese chickens and suggests that the potential impact of GyVg1 on the chicken industry may be of concern.

Taxonomic review of the Calotesversicolor complex (Agamidae, Sauria, Squamata) in China, with description of a new species and subspecies

Caloteswangisp. nov., a new species of the agamid genus Calotes Cuvier, 1817, from southern China and northern Vietnam, is described. This species can be distinguished from all known congeners by a combination of morphological characteristics and genetic divergence in the mitochondrial tRNA, ND2, and CO1 genes. Molecular phylogenetic analysis revealed that the new species was formed as a monophyletic group and that considerable genetic divergence existed between its congeners (minimum p-distance, 4.6%). Caloteswangisp. nov. is distinguished by a combination of the following characteristics: average SVL < 90 mm for adult males; 10-14 dorsal eyelid scales; scales on side of neck and adjacent shoulder area pointing obliquely upward; keels on neck scales weakly to strongly developed; fold in front of the shoulder absent; pair of dark triangular patches extending from the front of the shoulder to the jaw angles; and orange coloration of the tongue. Caloteswangisp. nov. is similar to C.irawadi but differs in having scales between the nasal shield and the orbit and a fourth toe with a claw that can reach between the eyes and tympanum (even to the snout when hind the limbs are adpressed forward). Phylogenetic analyses revealed two well-supported subspecies, Lineages A and B in C.wangisp. nov., with mean uncorrected p-distances between them of 2%. We propose that Lineage A, which is mainly from the central and southern Wuzhi Mountains on Hainan Island, is a subspecies, C.w.hainanensisssp. nov. Lineage B mainly comprises individuals from other sites on the island plus the adjacent mainland, and is described as subspecies, C.w.wangissp. nov. A diagnostic key to all Calotes species of China is also provided.

Biotic resistance to fish invasions in southern China: Evidence from biomass, habitat, and fertility limitation

Understanding the mechanisms underlying the invasion success or failure of alien species can help to predict future invasions and cope with the invaders. The biotic resistance hypothesis posits that diverse communities are more resistant to invasion. While many studies have examined this hypothesis, the majority of them have focused on the relationship between alien and native species richness in plant communities, and results have often been inconsistent. In southern China, many rivers have been invaded by alien fish species, providing an opportunity to test the resistance of native fish communities to alien fish invasions. Using survey data for 60,155 freshwater fish collected from five main rivers of southern China for 3 years, we assessed the relationships between native fish richness and the richness and biomass of alien fishes at river and reach spatial scales, respectively. Based on two manipulative experiments, we further examined the impact of native fish richness on habitat selection and the reproductive ability of an exotic model species Coptodon zillii. We found no apparent relationship between alien and native fish richness, whereas the biomass of alien fish significantly decreased with increasing native fish richness. In experiments, C. zillii preferred to invade those habitats that had low native fish richness, given evenly distributed food resources; reproduction of C. zillii was strongly depressed by a native carnivorous fish Channa maculata. Together, our results indicate that native fish diversity can continue to provide biotic resistance to alien fish species in terms of limiting their growth, habitat selection, and reproduction when these aliens have successfully invaded southern China. We thus advocate for fish biodiversity conservation, especially for key species, to mitigate against the population development and ecological impact of alien fish species.

Association of Apolipoprotein E Gene Polymorphism with Type 2 Diabetic Nephropathy in the Southern Chinese Population

Background

Common polymorphisms within the apolipoprotein E (APOE) gene are rs429358 and rs7412, which result in three major alleles (ɛ2, ɛ3, and ɛ4) and six genotypes (E2/E2, E2/E3, E3/E3, E3/E4, E4/E4, and E2/E4). Although APOE gene polymorphisms have been suggested to be associated with the development of diabetic nephropathy (DN), their potential association remains unclear in different regions. This study aims to unveil the genetic effects of APOE gene polymorphisms on DN susceptibility and serum lipid profiles in southern Chinese population.

Methods

A total of 306 DN patients and 483 type 2 diabetic patients as controls were included in the study. The APOE gene polymorphisms were analyzed by polymerase chain reaction (PCR) microarray gene chip. Relevant medical records and information of these participants were collected.

Results

There were statistically significant differences (p < 0.05) in gender, SBP, hypertension, hyperuricemia, UTP, TG and HDL-C between DN patients and controls. DN patients exhibited a higher frequency of the ε2 allele and E2/E3 genotype than controls (p < 0.001). Logistic regression analysis indicated that the ε2 allele and E2/E3 genotype were independent risk factors (adjusted OR: 3.237, 95% CI: 1.789-5.854, p < 0.001; adjusted OR: 3.453, 95% CI: 1.873-6.368, p < 0.001), while the ε3 allele or E3/E3 genotype might serve as protective role (adjusted OR: 0.395, 95% CI: 0.255-0.612, p < 0.001) for development of DN.

Conclusion

Our study indicates a correlation between APOE polymorphisms and DN in the southern Chinese Hakka population. Specifically, individuals carrying the APOE ε2 allele and E2/E3 genotype are at a higher risk of developing DN. Conversely, those with the APOE ε3 allele and E3/E3 genotype have a lower risk of DN in southern Chinese population.

A review of the spider genus Sinoalaria (Araneae, Theridiosomatidae), with the descriptions of four new species and two new combinations

The spider genus Sinoalaria Zhao & Li, 2014 is redefined and reviewed. A total of ten species are studied, including four new species: S.chi Yu & Lin, sp. nov. (♂♀), S.shenhei Yu & Lin, sp. nov. (♀), S.shuidi Yu & Lin, sp. nov. (♀), S.xiaotu Yu & Lin, sp. nov. (♂♀). Two new combinations are proposed: Sinoalarianitida (Zhao & Li, 2012), comb. nov. and S.prolata (Zhao & Li, 2012), comb. nov., both transferred from Karstia Chen, 2010. The material of six known species were re-examined and photographed, including the type species, S.chengguanensis (Zhao & Li, 2012). A key is provided for all species of the genus, as well as diagnoses, illustrations, and a distribution map.

Notes on twelve species of jumping spiders from Hainan Island, China (Araneae, Salticidae)

Three new genera and eleven new species are reported from Hainan Island, China. The new genera are Logunattusgen. nov., including L.dufuisp. nov. (♂), and the generotype L.libaiisp. nov. (♂♀), Qiongattusyuanyeaegen. et sp. nov. (♂♀), and Spiralembolusgen. nov., including the generotype S.yinggelingsp. nov. (♂♀), and S.yuisp. nov. (♂♀). Another six new species are Carrhotusqingzhaoaesp. nov. (♂♀), Gedealiangweiisp. nov. (♂♀), Heliophanoidesmoisp. nov. (♂), Indopadillasongisp. nov. (♂♀), Myrmarachnemixiaoqiisp. nov. (♂♀), and Nandiciusshihaitaoisp. nov. (♂♀). The unknown female of the endemic species, Pancoriushainanensis Song & Chai, 1991 is also described for the first time. Diagnostic photos of these species are provided.

Molecular spectrum of α- and β-thalassemia among individuals of reproductive age in the Zhuhai region of southern China

INTRODUCTION

Thalassemia is the most common monogenic disease in South and Southeast Asia. An accurate assessment of the relative frequency and composition of thalassemia mutations is important for the design of appropriate strategies to prevent the disease. In this study, we aimed to decode the molecular characterization of thalassemia mutations in Zhuhai region of southern China.

METHODS

A total of 8048 individuals who were potential thalassemia carriers were enrolled. Gap-polymerase chain reaction (Gap-PCR) and reverse dot-blot (RDB) hybridization methods were employed to detect common deletional and non-deletional thalassemia mutations. Multiplex ligation dependent probe amplification (MLPA) and Sanger sequencing were used to analyze and verify rare and complex mutations.

RESULTS

We diagnosed 3433 individuals as thalassemia carriers or patients. Of these, 2395 (69.76%) individuals with α-thalassemia harbored 13 α-globin gene mutations. The three most common α-thalassemia mutations were --^SEA (60.08%), -α^3.7 (20.62%) and -α^4.2 (9.25%). We diagnosed 903 (26.30%) individuals with β-thalassemia and identified 20 β-globin gene mutations, of which the three most frequent were CD41/42 (-TCTT) (38.10%), IVS-II-654 (C>T) (23.69%) and TATAbox-28 (A>G) (15.18%). In addition, we identified 15 rare thalassemia variants. We also summarized the association between the thalassemia genotype and hematological parameters, which demonstrated the broad phenotypic heterogeneity caused by globin gene mutations.

CONCLUSION

This is the first survey of thalassemia molecular epidemiology and hematological phenotype in Zhuhai region. It uncovered a high prevalence and complex molecular spectrum of thalassemia. These findings can be used as a basis for thalassemia diagnosis, counseling and prevention management.

Comparative genomic analysis of esophageal squamous cell carcinoma among different geographic regions

Introduction

Esophageal squamous cell carcinoma (ESCC) shows remarkable variation in incidence, survival, and risk factors. Although the genomic characteristics of ESCC have been extensively characterized, the genomic differences between different geographic regions remain unclear.

Methods

In this study, we sequenced 111 patients with ESCC from northern (NC) and southern (SC) China, combined their data with those of 1081 cases from previous reports, and performed a comparative analysis among different regions. In total, 644 ESCC cases were collected from six geographic regions (NC, SC, Xinjiang, China [XJC], Japan [JP], Vietnam [VN], and Europe & America [EA]) as the discovery cohort. Validation cohort 1 included 437 patients with ESCC from the NC region. Validation cohort 2 included 54 and 57 patients from the NC and SC regions, respectively.

Results

Patients with ESCC in different regions had different genomic characteristics, including DNA signatures, tumor mutation burdens, significantly mutated genes (SMGs), altered signaling pathways, and genes associated with clinical features. Based on both the DNA mutation signature and the mutation profile of the most common genes, the NC and SC groups were clustered close together, followed by the JP, XJC, EA, and VN groups. Compared to patients with ESCC from SC, SMGs, including KMT2D, FAT1, and NOTCH1 were more frequently identified in patients with ESCC from NC. Furthermore, some genes (TDG and DNAH8) correlated with overall survival in completely opposite ways in patients with ESCC from different geographical regions.

Conclusions

Our study provides insights into genomic differences in ESCC among different regions. These differences may be related to differences in environmental carcinogens, incidence, and survival.

Prevalence of hepatitis B virus infection among pregnant women in the mountainous regions of southern China: A retrospective single-center study

BACKGROUND

Hepatitis B virus (HBV) infection remains a major public health issue worldwide. Moreover, its prevalence varies significantly in different geographic areas of China. The current study aimed to assess the prevalence of HBV infection among Hakka pregnant women in Meizhou, a remote mountainous region in southern China.

METHODS

This research was performed between January 2015 and December 2020. In total, 16,727 pregnant women receiving antenatal care at Meizhou People's Hospital were included in the analysis. All pregnant women were screened for serum HBV markers.

RESULTS

The prevalence rates of hepatitis B surface antigen (HBsAg) and hepatitis B surface antibody positivity among the participants were 11.74% (n = 1964) and 48.00% (n = 8029), respectively. The overall prevalence rates of susceptibility to infection, HBV immunity, previous/occult infection, inactive HBsAg carrier, and active infection were 36.16%, 33.61%, 16.94%, 8.11%, and 2.30%, respectively. According to age distribution, the prevalence rate of HBsAg positivity elevated concomitantly with increasing age (p < 0.001). From 2015 to 2020, the prevalence rate of HBsAg positivity decreased from 14.50% to 8.19% and that of hepatitis B pre-core antigen positivity from 4.42% to 2.31%. In addition, pregnant women with HBsAg-positive status were more likely to present with gestational diabetes, thrombocytopenia, and anemia than those with HBsAg-negative status.

CONCLUSION

The HBV infection rate remains high among pregnant women in the indigenous Hakka population in southern China. To prevent vertical transmission, cautious surveillance of maternal HBV infection status should be considered in Hakka pregnant women in Meizhou.

The associations between body dissatisfaction, exercise intensity, sleep quality, and depression in university students in southern China

Background

In recent years, depression in early adulthood has become an urgent global public health concern. The university years mark a transitional period from adolescence to adulthood. Young people are required to face academic and life pressures independently, which increases the risk of mental health problems in university.

Purpose

The main goal of the current study was to explore the sex differences in depression, body dissatisfaction, sleep quality, and exercise intensity among university students in southern China and to analyze the factors affecting the level of depression among university students.

Methods

In total, 1,258 university students aged 18-23 years were recruited for this study. All participants completed anthropometric measurements, the Self-rating Depression Scale, Physical Activity Rating Scale, and Pittsburgh Sleep Quality Index. Body dissatisfaction levels were measured using sex-appropriate silhouettes.

Results

Compared with young women, young men had higher exercise intensity and sleep quality, whereas young women's body dissatisfaction and depression levels were significantly higher than those of young men. Sleep quality score (β = 0.34, p < 0.01), sex (β = 0.15, p < 0.01), physical activity score (β = -0.14, p < 0.01), and body dissatisfaction (β = 0.14, p < 0.01) were significant predictive factors of the Self-rating Depression Scale score.

Conclusion

Low levels of physical dissatisfaction have a positive effect on depression, and high levels of physical activity and quality sleep can also improve depressive symptoms. At the same time, increasing body satisfaction has the effect of increasing physical activity and improving sleep quality. Therefore, there is great potential to prevent and ameliorate depression by reducing body dissatisfaction.

Two new species of Sinopoda from China, with first description of the male of S.horizontalis Zhong, Cao & Liu, 2017 (Araneae, Sparassidae)

Three species of spider genus Sinopoda Jäger, 1999 are reported from southern China. Two of them are described as new to science: S.guiyang Zhang, Yu & Zhong, sp. nov. and S.xishui Zhang, Yu & Zhong, sp. nov., both from Guizhou Province. The male of S.horizontalis Zhong, Cao & Liu, 2017 is described for the first time based on new material from the type locality, Wuyishan National Nature Reserve, Fujian Province, China. Detailed descriptions, diagnoses, photographs and a distribution map of the three species are provided.

The Carbon Sink Potential of Southern China After Two Decades of Afforestation

Afforestation and land use changes that sequester carbon from the atmosphere in the form of woody biomass have turned southern China into one of the largest carbon sinks globally, which contributes to mitigating climate change. However, forest growth saturation and available land that can be forested limit the longevity of this carbon sink, and while a plethora of studies have quantified vegetation changes over the last decades, the remaining carbon sink potential of this area is currently unknown. Here, we train a model with multiple predictors characterizing the heterogeneous landscapes of southern China and predict the biomass carbon carrying capacity of the region for 2002-2017. We compare observed and predicted biomass carbon density and find that during about two decades of afforestation, 2.34 PgC have been sequestered between 2002 and 2017, and a total of 5.32 Pg carbon can potentially still be sequestrated. This means that the region has reached 73% of its aboveground biomass carbon carrying capacity in 2017, which is 12% more than in 2002, equal to a decrease of 0.77% per year. We identify potential afforestation areas that can still sequester 2.39 PgC, while old and new forests have reached 87% of their potential with 1.85 PgC remaining. Our work locates areas where vegetation has not yet reached its full potential but also shows that afforestation is not a long-term solution for climate change mitigation.

Begoniaparvibracteata, a new species in Begonia sect. Platycentrum (Begoniaceae) from Guangxi of China, based on morphological and molecular evidence

The previously reported begonias in a limestone forest of Guangxi mainly belong to Begoniasect.Coelocentrum Irmscher. In this article, we described and illustrated a new species in sect. Platycentrum (Klotzsch) A.DC., Begoniaparvibracteata X.X.Feng, R.K.Li & Z.X.Liu, which was discovered in a karst forest of south-western Guangxi. The begonia shows high morphological similarity to B.subhowii S.H. Huang and B.psilophylla Irmscher, but differs from the latter two in its narrower oblique-ovate asymmetric leaf blade, 4 (occasionally 6) tepals of pistillate flower and smaller membranous inflorescence bracts. Molecular phylogenetic analysis, based on ITS sequence data, supports the new species as monophyletic and distinct from B.subhowii and B.psilophylla. Considering its narrow distribution and the disturbance of human activities, the conservation status of new taxon is evaluated as "Vulnerable" (VU B1, B2 ab (i, iv, v), D2) according to the IUCN Red List Categories and Criteria.

A high genetic diversity of Enterocytozoon bieneusi in diarrheic pigs in southern China

Enterocytozoon bieneusi is an important pathogen that is responsible for over 90% of documented cases of human microsporidiosis worldwide, causing a threat to public health and husbandry development. In immunocompromised patients, it can cause persistent diarrhoea, wasting diathesis and malabsorption and developing life-threatening chronic diarrhoea. However, there was little information on the prevalence and multilocus genotypes of E. bieneusi in diarrheic pigs in three provinces of southern China. In this study, 1254 faecal samples of diarrheic pigs were collected from 37 pig farms in Hunan, Jiangxi, and Fujian provinces in southern China, and were investigated the prevalence and genotypes of E. bieneusi by nested polymerase chain reaction (PCR) based on the internal transcribed spacer (ITS) region of the nuclear ribosomal DNA gene. The overall prevalence of E. bieneusi was 5.7% (72/1254) in three provinces. Furthermore, the difference was statistically significant (p < 0.001) in the prevalence of E. bieneusi in age groups. ITS sequence analysis revealed that 13 E. bieneusi genotypes were identified, including 8 known genotypes (EbpC, n = 30; Henan-IV, n = 21; CH5, n = 6; EbpA, n = 3; KIN-1, n = 2; O, n = 1; GX3, n = 1; CHS5, n = 1) and 5 novel genotypes (JX1, n = 2; JX2, n = 1; JX3, n = 2; FJ1, n = 1; FJ2, n = 1), and the genotype EbpC was the preponderant genotype. Phylogenetic analysis indicated that all genotypes of E. bieneusi were clustered as the zoonotic group 1. Moreover, a high genetic diversity of E. bieneusi were identified in this study, which the 64, 57, 52 and 64 samples were identified by multilocus sequence typing (MLST) at MS1, MS3, MS4 and MS7 loci, respectively. Then, 45 samples were successfully amplified and sequenced at four loci, forming 41 distinct multilocus genotypes (MLGs). These findings suggest that diarrheic pigs may potentially threaten to transmit E. bieneusi to humans, revealing E. bieneusi genetic variability in diarrheic pigs in three provinces of southern China.

1000-770 BCE)

The Wanfunao site was a large Chu settlement in Zhou Dynasty. It was located on an alluvial plain along the Yangtze River in the Yichang section. The region around the site comprised mountains, hills, and plains, which was a compatible environment for the cultivation of various crops. Previous studies have suggested that the middle and lower reaches of the Yangtze River are one of the most productive regions for rice cultivation. Besides rice, however, seven dryland crops have been found at the Wanfunao site: foxtail millet, broomcorn millet, wheat, barley, oat, buckwheat, and adzuki bean. Among them, foxtail millet and rice are most ubiquitous. The crop assemblage has revealed that the northern dryland crops, including those were newly adapted cereals such as foxtail millet, wheat, and barley, gradually dispersed southward and became a part of the diet along with rice. This can be attributed to southern Chinese inhabitants' reclamation of the hilly environment for agriculture. Although communities in southern China had cultivated rice on the plains for thousands of years, newly introduced dryland crops from north China adapted to mountainous environments better. The development of multi-cropping systems in southern China likely involved changes in agricultural ontology associated with the adaptation of northern crops in southern environments newly encountered. Additionally, the assemblage of foxtail millet grain/rice spikelet base in the site may have been used for livestock feeding. A wide range of landforms, compatible farming, and surplus agricultural products for husbandry may have been a part of the economic foundation that facilitated the rise of Chu.

Phylogeographical Analysis of the Freshwater Gudgeon Huigobio chenhsienensis (Cypriniformes: Gobionidae) in Southern China

The freshwater gudgeon Huigobio chenhsienensis (Cypriniformes: Gobionidae) is a small fish endemic to southern China. In this study, we used mitochondrial cytochrome b gene (Cytb), from wide-ranging samplings of H. chenhsienensis from the Ou River (the central of southern China) to the Yangtze River Basin (the northernmost part of southern China) to explore genetic variations and the evolutionary history of H. chenhsienensis in southern China. In total, 66 haplotypes were identified from Cytb sequences of 142 H. chenhsienensis individuals, which could be divided into lineages A, B, and C with divergence times of ~4.24 Ma and ~3.03 Ma. Lineage A was distributed in the lower reaches of the Yangtze River, the Oujiang River, and the Jiao River, lineage B was distributed in the Qiantang River and the Cao'e River, whereas lineage C was restricted to the Poyang Lake drainage from the middle reaches of the Yangtze River. Lineage A could be subdivided into sub-lineages A-I, A-II, A-III, and A-IV, with divergence times of 1.30, 0.97, and 0.44 Ma. Lineage C could be subdivided into sub-lineages C-I and C-II, with a divergence time of 0.85 Ma. Our findings indicate that climate change during the Pliocene and Pleistocene eras, as well as the limited dispersal ability of H. chenhsienensis, have been major drivers for shaping the phylogeographical patterns of H. chenhsienensis.

in Pigs with Diarrhea in Southern China

Entamoeba spp. is a common zoonotic intestinal protozoan that can parasitize most vertebrates, including humans and pigs, causing severe intestinal diseases and posing a serious threat to public health. However, the available data on Entamoeba spp. infection in pigs are relatively limited in China. To characterize the infection of Entamoeba spp. within pigs in southern China, 1254 fecal samples of diarrheic pigs were collected from 37 intensive pig farms in Hunan, Jiangxi and Fujian provinces and the infection of Entamoeba spp. was investigated based on the small subunit rRNA (SSU rRNA) gene. The overall infection rate of Entamoeba spp. was 58.4% (732/1254), including 38.4% (118/307) in suckling piglets, 51.2% (153/299) in weaned piglets, 57.9% (55/95) in fattening pigs and 73.4% (406/553) in sows, respectively. Moreover, age and the sampling cities in Jiangxi and Fujian provinces were found to be the key factors influencing the infection of Entamoeba spp. (p < 0.05). Two subtypes (ST1 and ST3) with a zoonotic potential of Entamoeba polecki and Entamoeba suis were detected in all age groups of pigs and all sampling areas, with the predominant species and predominant subtype being E. polecki (91.3%, 668/732) and E. polecki ST1 (573/668), respectively, and E. polecki ST1 + E. polecki ST3 (78.6%, 239/304) being the most frequently detected form of mixed infection. Severe Entamoeba spp. infection and zoonotic subtypes were found in this study, exposing a large public health problem in the study area, and strategies need to be implemented to eliminate the risk in the future.

Molecular Detection and Characterization of Giardia duodenalis in Farmed Pigs in Three Provinces of Southern China

Giardia duodenalis is a flagellated zoonotic parasite that can infect various animals and humans, causing economic losses in husbandry and detriments to public health. Although it has been reported in pigs worldwide, there are few reports on the prevalence and assemblages of G. duodenalis infection in pigs in China. In this study, the 396 pig fecal samples were randomly collected from seven farms in Zhejiang, Guangdong and Yunnan provinces in southern China, and were examined by means of the nested PCR amplification of β-giardin (bg), glutamate dehydrogenase (gdh), and triose phosphate isomerase (tpi) for the detection of G. duodenalis. Overall, 21 fecal samples were positive for G. duodenalis, with a prevalence of 5.3%. Three risk factors are associated with G. duodenalis infection, namely, region, age and gender. Moreover, 13, six and two samples were successfully amplified at the bg, gdh and tpi gene loci, respectively. Three assemblages of G. duodenalis were identified, including assemblage E (n = 17), assemblage A (n = 3) and assemblage B (n = 1). Assemblage E was the dominating genotype and was distributed in three provinces. These assemblages of G. duodenalis have also been found in human beings, non-human primates, sheep, goats and cattle, which further reveals that farmed pigs pose a potential threat to public health.

Risk factors for rebleeding in patients with obscure gastrointestinal bleeding from southern China

Background

To identify the risk factors associated with rebleeding in obscure gastrointestinal bleeding (OGIB) patients from southern China.

Methods

This retrospective study involved 229 patients who underwent small bowel endoscopy in our hospital between 1 January 2018 and 1 December 2020. The clinical characteristics and risk factors related to rebleeding were retrospectively evaluated.

Results

Rebleeding patients were significantly older than non-rebleeding patients (53.0 ± 15.9 vs. 46.2 ± 17.8 years), had lower hemoglobin concentrations (89.2 ± 28.1 vs. 126.2 ± 25.1 g/L), and higher blood urea nitrogen concentrations (5.4 ± 2.6 vs. 4.5 ± 2.2 µmol/L), respectively. A higher percentage of rebleeding patients had diabetes mellitus (13.9% vs. 2.9%) and overt bleeding (70.4% vs. 38.6%), and required blood transfusions (43.1% vs. 8.0%), compared with non-rebleeding patients, respectively. Multivariate logistic analysis indicated that drinking alcohol (odds ratio (OR): 9.27; 95% confidence interval (CI) = 1.35–63.78), anemia (OR: 17.38; 95% CI = 5.48–55.10), and blood transfusion (OR: 3.76; 95% CI = 1.04–13.56) increased the risk of rebleeding in OGIB patients.

Conclusion

Our data suggested that OGIB patients who drink alcohol, have anemia, and require blood transfusion have an increased risk of rebleeding.

Begoniapseudoedulis, a new species in Begoniasect.Platycentrum (Begoniaceae) from southern Guangxi of China

Begoniapseudoedulis, a new species in Begoniasect.Platycentrum (Klotzsch) A.DC. (Begoniaceae) from southern Guangxi of China, is here described and illustrated. It morphologically resembles B.edulis H.Lév. and B.dielsiana E.Pritz. ex Diels but differs easily by its hairy petioles and inflorescences, and red hispidulous flower tepals, ovary and capsules. The molecular phylogenetic analysis based on ITS supported that the new species was a monophyletic lineage, separating from both B.dielsiana and B.edulis. Due to its isolated distribution with several small populations, which are possibly disturbed by human activities, the species is considered as "Near Threatened" (NT) according to the IUCN Red List Categories and Criteria.

Geographic Variation of Phyllodiaptomus tunguidus Mitogenomes: Genetic Differentiation and Phylogeny

Phyllodiaptomus tunguidus (Copepoda: Calanoida) is largely endemic to and widespread in freshwater in southern China, where it inhabits a complex landscape from lowland to highland across an elevation gradient of 2000m. A deep genetic differentiation can be expected between its most distant geographic populations. Here, we sequenced nine mitogenomes from diverse populations. All mitogenomes contained 37 genes, including 13 protein-coding genes (PCG), two rRNA genes, 22 tRNA genes and one control region. Their base composition, genetic distance and tRNA structure indeed revealed a wide differentiation between mitogenomes. Two P. tunguidus from Guangxi near Vietnam differed from the other seven by up to 10.1%. Their tRNA-Arg had a complete clover-leaf structure, whereas that of the others did not contain an entire dihydrouridine arm. The nine mitogenomes also differed in the length of rRNA. NJ, ML, and Bayesian analyses all split them into two clades, viz. the two P. tunguidus from Guangxi (Clade 1), and the other seven (Clade 2). Both the structure and phylogeny of the mitogenomes suggest that P. tunguidus has complex geographic origin, and its populations in Clade 1 have long lived in isolation from those in Clade 2. They currently reach the level of subspecies or cryptic species. An extensive phylogenetic analysis of Copepoda further verified that Diaptomidae is the most recently diverging family in Calanoida and that P. tunguidus is at the evolutionary apex of the family.

Two new species and one new record of Neoperla (Plecoptera, Perlidae) from Guangxi Zhuang Autonomous Region, China

Three species of the Neoperlamontivaga group are described from Guangxi Zhuang Autonomous Region of southern China, including two new species, N.falcatata sp. nov. and N.shangsiensis sp. nov., and a new record for Guangxi: N.bilineata Wu & Claassen, 1934. Illustrations and color images are provided for the three species mentioned above, and the new species is compared with related congeners in the group. Notes on the distribution of the Neoperla species known from Guangxi are also given.

in Diarrheic Pigs in Southern China

Blastocystis sp. is a common pathogen that infects the intestines of humans and animals, causing a threat to public health. However, little information on the prevalence and subtypes of Blastocystis sp. in diarrheic pigs in China is available. Herein, 1254 fecal samples were collected from diarrheic pigs in 37 intensive pig farms in Hunan, Jiangxi, and Fujian provinces in southern China, and the prevalence and subtypes of Blastocystis sp. were investigated. Blastocystis sp. was detected by PCR assay, which amplified the small subunit rRNA (SSU rRNA) gene. Overall prevalence of Blastocystis sp. was 31.4% (394/1254), including 21.5% (66/307), 33.1% (99/299), 58.9% (56/95), and 31.3% (173/553) in suckling piglets, weaned piglets, fattening pigs, and sows, respectively. Moreover, age and region factors were significantly related to prevalence of Blastocystis sp. (p < 0.05). Four Blastocystis sp. subtypes were identified, including ST1, ST3, ST5, and ST14. The preponderant subtype was ST5 (76.9%, 303/394). To our knowledge, ST14 was firstly found in pigs in China. The human-pathogenic subtypes (ST1, ST3, ST5, and ST14) that were observed in this study indicate a potential threat to public health. These findings provided a new sight for studying the genetic structure of Blastocystis sp.

Prevalence of allergen-specific IgE in southern China: a multicenter research

Identifying allergen distribution is meaningful and significant for effective diagnosis and treatment of allergic diseases. This study compared the allergen sensitivity in four southern China cities. We enrolled 55,432 participants (27,408 male, 28,024 female) between 2007 and 2019. The allergen-specific IgE levels were compared by the χ2 test. The five prevalent sensitivities were for mite mix (10,985, 19.82%), cockroach (4,860, 8.77%), crab (4,450, 8.03%), fish mix (3,874, 6.99%), and house dust (3,486, 6.29%). Almost all allergen sensitivities decreased with age, particularly from infant to middle aged participants (p < 0.05). An exception was Shenzhen, where food allergen positive rates remained constant in all age groups studied. The proportion of male sensitive to at least one food allergen (OR 1.130; 95% CI 1.088–1.174, p < 0.0025) or aeroallergen (OR, 1.117; 95% CI, 1.078–1.158, p < 0.0025) was higher than female in all four cities. Except for dog dander and tree mix, all aeroallergens differed significantly between seasons (p < 0.05). Liuzhou had the highest rates of food allergen- and aeroallergen-positive participants. The allergen-specific IgE distribution differed among the studied cities, with significant seasonal differences. Young age, male sex, and aeroallergens were risk factors for allergic disease.

Begonia shenzhenensis, a new species of Begoniaceae from Guangdong, China

Begonia shenzhenensis D.K.Tian & X.Yun Wang, sp. nov., a new species in Begonia sect. Platycentrum of Begoniaceae from Shenzhen of Guangdong province, China, is described and illustrated. Morphologically, it is primarily similar to B. coelocentroides in the same section but differs by its denser hairs on leaf, petiole, and pedicel, abtuse anther apex, hairy ovary, and narrower adaxial fruit wing. Based on only one small population found to date, its conservation status is assigned to Critical Endangered according to the IUCN Red List Categories and Criteria.

First direct evidence of conservative foraging ecology of early Gigantopithecus blacki (~2 Ma) in Guangxi, southern China

OBJECTIVES

Gigantopithecus blacki, the largest hominoid known, is one of the representative Pleistocene mammals in southern China and northern Southeast Asia. Here we investigate the feeding ecology of G. blacki in its core habitat (Guangxi, Southern China) during the early Early Pleistocene, which was the early period in its evolution.

MATERIALS AND METHODS

The stable isotopic (C, O) analysis of tooth enamel of the fauna associated with G. blacki (n = 58), including the largest number of G. blacki teeth (n = 12) to date from the Liucheng Gigantopithecus Cave (~2 Ma), Guangxi, China, is undertaken.

RESULTS

The δ¹³ C values of Liucheng fauna range from -12.9 to -19.0‰ with an average of -16.1 ± 1.3‰ (n = 58) and the δ¹⁸ O values range from -4.3 to -9.6‰ with an average of -6.9 ± 1.2‰ (n = 58). The δ¹³ C values of G. blacki range from -15.9‰ to -17.0‰ with an average of -16.5 ± 0.4‰ (n = 12), and the δ¹⁸ O values vary from -5.9‰ to -7.5‰ with an average of -6.6 ± 0.5‰ (n = 12).

CONCLUSIONS

The isotopic data show Guangxi was characterized by closed C₃ forest and humid climate in the early Early Pleistocene. Niche partitioning is found among G. blacki, Sinomastodon, Ailuropoda and Stegodon, the typical megafauna in South China in the early Early Pleistocene. This could be one of the important factors for them to co-exist until the Middle Pleistocene. Smallest isotopic variations of G. blacki are found compared with those of contemporary animals, indicating a conservative foraging ecology i.e., limited foraging area and/or narrow dietary flexibility. Furthermore, the more confined foraging ecology of G. blacki is also seen in comparison with fossil and extant large-bodied primates. However, the unique dietary pattern of G. blacki does not seem to have hindered its survival. The environment in Guangxi during the early Early Pleistocene offered the suitable conditions for G. blacki to become one of the typical species in the faunal assemblages.

Four new coelotine species (Araneae, Agelenidae, Coelotinae) from South China, with the first description of the male of Coelotes septus Wang, Yin, Peng & Xie, 1990

Four new species are described from Jinggang Mountain National Nature Reserve, Jiangxi Province of southern China: Draconarius lingdang sp. nov. (♂♀), D. substrophadatus sp. nov. (♀), Orumcekia cipingensis sp. nov. (♀) and Tonsilla shuikouensis sp. nov. (♀). Additionally, Coelotes septus Wang, Yin, Peng & Xie, 1990 is redescribed and its male is described for the first time.

Distribution and molecular characterization of avian infectious bronchitis virus in southern China

Avian infectious bronchitis virus (IBV) is causing considerable economic losses in the world poultry industry. The main difficulty of prevention and control of IB disease is the numerous genotypes and serotypes. The genetic analysis of IBV was mainly based on the S1 gene which played an important role in infectivity. In the study, One hundred and thirty-nine strains of avian infectious bronchitis virus were isolated from chickens showing signs of disease in southern China during the period from April 2019 to March 2020. The nucleotide and amino acid sequences from the isolated field strains were compared to 22 published references. Nucleotide homologies ranged from 64.5% to 100% and amino acid homologies ranging from 70% to 99.8%. Six genotype IBV strains were co-circulating in southern China. QX-type was still the most dominant genotype. Alignment of nucleotide and amino acid sequences of S1 gene revealed that the substitutions, insertions and deletions are widely among isolated strains. Recombination analysis showed that there is a large number of recombinant strains amongst these isolates, forming new sub branches, subtypes and variants. Therefore, long-term continuing surveillance is necessary for IBV prevention and control.

A new species of Notomastus (Annelida, Capitellidae) from southern China, with remarks on its morphology and distribution

The genus Notomastus is frequently encountered in Chinese waters. However, its species richness is poorly understood. In this study, a Notomastus species obtained from Xiamen Bay, southern China, was described and illustrated as a new species (N.sunaesp. nov.), based on morphological and molecular analyses. The new species is characterized by having uniramous chaetiger 1, the presence of palpode and eyespots on prostomium, chaetiger 11 with notopodial capillaries and neuropodial hooded hooks, and notopodial lobes with simple epithelial extensions on far posterior abdomen. With additional specimens collected from several localities along the southern coasts of China, the morphology and geographical distribution of the new species are discussed. A key is also provided for Notomastus species with neuropodial hooks in thoracic chaetiger 11.

Hemoglobin variants in southern China: results obtained during the measurement of glycated hemoglobin in a large population

Objectives

Hemoglobin (Hb) variant is one of the most common monogenic inherited disorders. We aimed to explore the prevalence and hematological and molecular characteristics of Hb variants in southern China.

Methods

We collected blood samples from all patients with suspected variants found during HbA1c measurement via a cation-exchange high-performance liquid chromatography system (Bio-Rad Variant II Turbo 2.0) or a capillary electrophoresis method (Sebia Capillarys). Hematological analysis, Sanger sequencing, and gap-PCR were performed for these samples.

Results

Among the 311,024 patients tested, we found 1,074 Hb variant carriers, including 823 identified using Capillarys and 251 using Variant II Turbo 2.0, with a total carrier rate of 0.35%. We discovered 117 types of Hb variants (52 HBB, 47 HBA, and 18 HBD mutations) containing 18 new mutations. The most common variant found was Hb E, followed by Hb New York, Hb J-Bangkok, Hb Q-Thailand, Hb G-Coushatta, Hb G-Honolulu, Hb G-Taipei, and Hb Broomhill. Most heterozygotes for the Hb variant exhibited normal hematological parameters. However, most patients with compound heterozygotes for the Hb variant and thalassemia showed varied degrees of microcytic hypochromic anemia.

Conclusions

The prevalence of hemoglobin variants remains high and exhibits genetic diversity and widespread distribution in the population of southern China.

[Distribution Characteristics and Migration Rules of Pollutants in Sediments of Reservoirs with Eucalyptus Plantation, Southern China]

The safety of water quantity and quality caused by large-scale blackwater in reservoirs with Eucalyptus plantation is currently a point of great interest. Eucalyptus is largely planted in southern China, especially in Nanning, Guangxi, where more than 90% of the drinking water source reservoirs are surrounded by Eucalyptus, and different degrees of blackwater often occur in many reservoirs. Recent research has demonstrated that reservoir sediments play an important role in the migration and transformation of Fe²⁺, Mn²⁺, S^2-, and dissolved organic carbon (DOC) in the overlying water. It is of great significance to explore the distribution characteristics and migration rules of pollutants in the sediment-water interface to reveal the mechanism of blackwater in reservoirs. Experiments were carried out three times in a typical blackwater reservoir (Tianbao Reservoir) in southern China from July to December 2018. The distribution characteristics and seasonal variations of iron, manganese, sulfide, and organic matter in sediments were analyzed, focusing mainly on the profile distribution and migration direction of Fe²⁺, Mn^2+, S^2- and DOC in pore water during blackwater periods. The results showed that:① The content of iron and manganese in sediments of reservoirs with Eucalyptus plantation is high, far exceeding the background value of soil content in China. The content of iron, manganese, and total organic carbon (TOC) in the surface sediments increases simultaneously, mainly caused by the input and settlement of the material (litter, decomposed liquids. and soil particles) in the Eucalyptus forest around the reservoir. ② The concentration of Fe²⁺(16.99 mg·L^-1) and the content of DOC (36.80%) in pore water during the blackwater period are significantly higher than those in Taihu Lake during the black bloom (12.15 mg·L^-1, 10.78%). The mean concentrations of Fe²⁺ and Mn²⁺ are more than 300 times higher than that of S^2-, and the reduction conditions in the sediments are dominated by iron and manganese oxides. ③ The diffusion flux of Fe²⁺ is 27.4-33.5 mg·(m²·d)^-1, which is 32.6, 4.9, and 30.8 times higher than those of Taihu Lake, Aha Reservoir, and Hongfeng Lake, respectively. This implies strong Fe²⁺ release ability from sediments to the overlying water. As a positive correction exists between Fe²⁺ and DOC, the complex reaction between Fe²⁺ and organic matter is one of the most important causes of blackwater in reservoirs with Eucalyptus plantation.

Re-examination of the Chinese record of Opisthotropis maculosa (Squamata, Natricidae), resulting in the first national record of O. haihaensis and description of a new species

The taxonomic status of the previous record of Opisthotropismaculosa Stuart & Chuaynkern, 2007 from Guangdong and Guangxi, southern China, is revised based on the comparison of morphological and molecular data collected from the Chinese specimens and the holotype of O.maculosa from Thailand and O.haihaensis Ziegler, Pham, Nguyen, Nguyen, Wang, Wang, Stuart & Le, 2019 from Vietnam. Results reveal that the population from Shiwandashan Nature Reserve in southern Guangxi, China belongs to O.haihaensis, and represents the first national record for China; the populations from western Guangdong and southeastern Guangxi are described as a new species, Opisthotropishungtaisp. nov. We suggest that O.maculosa should be removed from the Chinese herpetofauna checklist. The new national record of O.haihaensis and the description of the new species bring the total number of Opisthotropis to 13 in China.

A qualitative study of zoonotic risk factors among rural communities in southern China

BACKGROUND

Strategies are urgently needed to mitigate the risk of zoonotic disease emergence in southern China, where pathogens with zoonotic potential are known to circulate in wild animal populations. However, the risk factors leading to emergence are poorly understood, which presents a challenge in developing appropriate mitigation strategies for local communities.

METHODS

Residents in rural communities of Yunnan, Guangxi and Guangdong provinces were recruited and enrolled in this study. Data were collected through ethnographic interviews and field observations, and thematically coded and analysed to identify both risk and protective factors for zoonotic disease emergence at the individual, community and policy levels.

RESULTS

Eighty-eight ethnographic interviews and 55 field observations were conducted at nine selected sites. Frequent human-animal interactions and low levels of environmental biosecurity in local communities were identified as risks for zoonotic disease emergence. Policies and programmes existing in the communities provide opportunities for zoonotic risk mitigation.

CONCLUSIONS

This study explored the relationship among zoonotic risk and human behaviour, environment and policies in rural communities in southern China. It identifies key behavioural risk factors that can be targeted for development of tailored risk-mitigation strategies to reduce the threat of novel zoonoses.

Epidemiology of electrical burns: a 10-year retrospective analysis of 376 cases at a burn centre in South China

OBJECTIVE

To investigate the epidemiological profile and associated outcomes of electrical injuries at a major burn centre in southern China.

METHODS

This retrospective study enrolled consecutive electrical burn patients admitted to the burn centre of the First Affiliated Hospital of Guangxi Medical University between 2008 and 2017. Demographic and clinical data and outcomes were recorded. Mann-Whitney U tests/Pearson's chi-squared tests were used to examine the differences between low-voltage and high-voltage injuries.

RESULTS

There were 217 high-voltage injuries and 159 low-voltage injuries. High-voltage burns were frequently observed between March and August, and low-voltage burns peaked between June and September. Burn patients were mainly men. Most burns occurred in participants aged 21 to 50 years and in industrial workers and electricians at work or householders at home. Only one person with high-voltage burns died (a mortality rate of 0.46%). Amputation rates were 37.33% for high-voltage burns and 22.01% for low-voltage burns. High-voltage injuries were associated with more extensive burns, longer hospital stays, and more complications and amputations.

CONCLUSIONS

More attention should be paid to prevention of electrical burns in male adults. Particular focus is needed on industrial workers, incidents in the spring and summer, and high-voltage injuries.

Analysis of genotype distribution of thalassemia and G6PD deficiency among Hakka population in Meizhou city of Guangdong Province

Objective

The aim of the study was to explore genotype distribution thalassemia and G6PD deficiency in Meizhou city, China.

Methods

A total of 16 158 individuals were involved in thalassemia genetic testing. A total of 605 subjects were screened for common Chinese G6PD mutations by gene chip analysis. Genotypes and allele frequencies were analyzed.

Results

A total of 5463 cases carried thalassemia mutations were identified, including 3585 cases, 1701 cases, and 177 cases with α‐, β‐, and α + β‐thalassemia mutations, respectively. ‐‐^SEA (65.12%), ‐α^3.7 (19.05%), and ‐α^4.2 (8.05%) deletion were the main mutations of α‐thalassemia, while IVS‐II‐654(C → T) (40.39%), CD41‐42(‐TCTT) (32.72%), ‐28(A → G) (10.11%), and CD17(A → T) (9.32%) mutations were the principal mutations of β‐thalassemia in Meizhou. There were significant differences in allele frequencies in some counties. Genetic testing for G6PD deficiency, six mutation sites, and one polymorphism were detected in our study. A total of 198 alleles with the mutation were detected among 805 alleles (24.6%). G6PD Canton (c.1376 G → T) (45.96%), G6PD Kaiping (c.1388 G → A) (39.39%), and G6PD Gaohe (c.95 A → G) (9.09%) account for 94.44% mutations, followed by G6PD Chinese‐5 (c.1024 C → T) (4.04%), G6PD Viangchan (c.871G → A) (1.01%), and G6PD Maewo (c.1360 C → T) (0.51%). There were some differences of the distribution of G6PD mutations among eight counties in Meizhou.

Conclusions

The ‐‐^SEA, ‐α^3.7, and ‐α^4.2 deletion were the main mutations of α‐thalassemia, while IVS‐II‐654(C → T), CD41‐42(‐TCTT), ‐28(A → G), and CD17(A → T) mutations were the principal mutations of β‐thalassemia in Meizhou. G6PD c.1376 G → T, c.1388 G → A, and c.95 A → G were the main mutations of G6PD deficiency. There were some differences of the distribution of thalassemia and G6PD mutations among eight counties in Meizhou.

A new species of the genus Takydromus (Squamata, Lacertidae) from southwestern Guangdong, China

A new species, Takydromusyunkaiensis J. Wang, Lyu, & Y.Y. Wang, sp. nov. is described based on a series of specimens collected from the Yunkaishan Nature Reserve located in the southern Yunkai Mountains, western Guangdong Province, China. The new species is a sister taxon to T.intermedius with a genetic divergence of 8.0–8.5% in the mitochondrial cytochrome b gene, and differs from all known congeners by a combination of the following morphological characters: (1) body size moderate, SVL 37.8–56.0 mm in males, 42.6–60.8 mm in females; (2) dorsal ground color brown; ventral surface green to yellow-green, but light blue-green on chin and throat, posteriorly green in adult males; (3) dorsolateral lines paired, strikingly yellowish-white bordered by black above and below, invisible or indistinct in juveniles and adult females; (4) flanks of body blackish brown with light brown marks in adult males; (5) presence of four pairs of chin-shields; (6) four supraoculars on each side; (7) presence of a row of supracilary granules that separate supracilaries from supraoculars; (8) two postnasals; (9) enlarged dorsal scales in six longitudinal rows on trunk of body, with strong keel; (10) enlarged ventral scales in six longitudinal rows, strongly keeled in males, smooth but outermost rows weakly keeled in females; (11) enlarged and keeled lateral scales in a row above ventrals; (12) femoral pores 2–3 on each side; (13) subdigital lamellae 20–23 under the fourth finger, 23–30 under the fourth toe; and (14) the first 2–3 subdigital lamellae under the fourth toe divided. The discovery of Takydromusyunkaiensissp. nov. brings the total number of species of this genus to 24, of which nine occur in mainland China.

A new species of Linan Hlavácˇ (Coleoptera, Staphylinidae, Pselaphinae) from Shenzhen, China

A new Chinese species of the genus Linan Hlaváč, 2003, L.qiniangmontissp. nov., is described based on two male and three female specimens from sifted leaf litter samples at Qiniang Mountain, Shenzhen City, Guangdong. The species can be readily recognized and separated from all congeners based on the forms of the male antennae, the metaventral processes, and the aedeagus.

Pronounced genetic differentiation in Fokienia hodginsii revealed by simple sequence repeat markers

Fokienia hodginsii is a Tertiary relict conifer of the monotypic genus Fokienia (Cupressaceae s.l.). Currently, the species is distributed in southern China, northern Vietnam, and northern Laos and listed as a "near threatened" species by the IUCN. In this study, a total of 427 individuals of F. hodginsii were sampled from China and Vietnam to characterize its genetic diversity and population differentiation. Based on the profiles of 12 simple sequence repeat (SSR) markers, we observed a high level of genetic diversity in F. hodginsii at the species level (H e =0.635), albeit slightly lower than that of its sister species Chamaecyparis obtusa. Signals of bottleneck events were detected in the populations GXDMS, GXHJ, V-PXB, and V-HB, probably due to Pleistocene glaciations or overexploitation in recent years. Pronounced genetic differentiation (F st   = 0.157) was found in this species. The inbreeding index (F is  = 0.176 ± 0.024) indicated that F. hodginsii has a mixed mating system. Significant correlation was found between the pairwise genetic differentiation and geographic distance (r = 0.882, p = 0.01), suggesting that genetic differentiation among the populations follows the model of isolation by distance (IBD). STRUCTURE analysis and principal coordinate analysis revealed that these populations were divided into four groups: the western China group located mainly in the Yunnan-Guizhou Plateau, the central China group located mostly in the Luoxiao Mountains and Nanling Mountains, the eastern China group located in the Wuyi Mountains and the Vietnam group containing two populations in Vietnam. The different terrains and elevations of populations may be the most likely factors leading to the differentiation between the western China group and the central China group, while the geographic isolation caused by the lack of appropriate habitats may greatly contribute to the differentiation between the central China group and the eastern China group. Based on the results, some conservation suggestions for this species are provided, such as establishing seed orchards and multiple nature reserves.

The influence factors of neonatal respiratory distress syndrome in Southern China: a case-control study

Objective: To explore the relevant influencing factors of neonatal respiratory distress syndrome (NRDS) in southern China and provide scientific basis for improving the quality of life for neonates.Methods: A retrospective analysis of 320 cases with NRDS neonates admitted from January 2015 to December 2017 in a neonatal department of a Maternal and Child Health Hospital in South China was conducted. Three hundred twenty non-NRDS patients admitted to the same hospital during the same period were also included as control. The basic characteristics were compared and the risk and protective factors for NRDS were evaluated by logistic regression analysis.Results: Univariate analysis showed that the difference in age, gestational age, fetal sex, mode of delivery, asphyxia, intrauterine distress, and gestational diabetes in the case group and the control group were significantly different (p < .05). The multivariate logistic regression analysis revealed that the age of pregnant women (OR ± 1.539, 95% CI ± 1.427-1.660), intrauterine distress (OR ± 2.427, 95% CI ± 1.079-5.458), and gestational diabetes (OR ± 2.881, 95% CI ± 1.271-6.532) were independent risk factors for NRDS. Meanwhile, gestational age (OR ± 0.588, 95% CI ± 0.508-0.681) was an independent protective factor for NRDS.Conclusions: The age of pregnant women, intrauterine distress, and gestational diabetes can increase the risk of NRDS, while long gestational age can reduce the risk of NRDS. Early detection, early diagnosis and early treatment of children with NRDS have achieved the purpose of improving the quality of life of children.

Youtuus, a new bamboo-feeding genus of the tribe Augilini with two new species from China (Hemiptera, Fulgoromorpha, Caliscelidae)

A new bamboo-feeding planthopper genus Youtuus Chen & Gong, gen. n. with two new species Y.erythrus Gong, Yang & Chen, sp. n. and Y.strigatus Gong, Yang & Chen, sp. n. (Hemiptera: Fulgoromorpha: Caliscelidae: Ommatidiotinae: Augilini), are described and illustrated from China. Keys to the genera of Augilini and the species of Youtuus Chen & Gong, gen. n. are given.

Molecular Spectrum of α- and β-Thalassemia Mutations in a Large Ethnic Hakka Population in Southern China

Thalassemia is one of the most prevalent inherited disorders in southern China. However, there have been few reports on molecular characterization of α- and β-thalassemia (α- and β-thal) in the large Hakka population living in Meizhou, a city with high incidence of thalassemia in China. A total of 11,631 in- and outpatients in the Hakka area were analyzed by DNA-based α- and β-thal testing. Of all the samples, 4280 mutant chromosomes were detected, accounting in a total of 35.98%, of which 2864 (24.82%) α-thal mutants were detected, 1268 (10.09%) β-thal mutants were detected, 148 (1.27%) α- and β-thal mutants were detected. The following mutations - -^SEA/αα (Southeast Asian deletion), β^A/β^A; αα/αα, IVS-II-654 (C>T) (HBB: c.316-197C>T)/β^A; αα/αα, codons 41/42 (-TCTT) (HBB: c.126_129delCTTT)/β^A; and -α^3.7/αα, β^A/β^A were the most common thalassemia genotypes. The most common thalassemia genotype in the Hakka population in Meizhou was α-thal. In order to reduce the incidence of severe thalassemia in children, a prevention and control strategy should be established based on the distribution data of thalassemia genotyping. Our findings provide a valuable reference for clinical institutions or local governments to reduce the prevalence of thalassemia in the subtropical regions in the world.

Immune protection conferred by three commonly used commercial live attenuated vaccines against the prevalent local strains of avian infectious bronchitis virus in southern China

Live attenuated vaccines are critical in the control of avian infectious bronchitis. It is necessary to know the protection conferred by commonly used commercial live vaccines. In this study, specific pathogen-free chicks were vaccinated with the commercial live vaccines H120, 4/91 and LDT3-A. Blood samples were collected at weekly intervals for the detection of IBV-specific antibodies and quantification of CD4⁺ and CD8⁺ T lymphocytes. At 21 days post-inoculation the vaccinated birds were challenged with the IBV prevalent local strains GX-YL5, GX-GL11079 and GX-NN09032, respectively. Trachea and kidney samples were collected at 5 days post-challenge for the detection of the virus. The results showed that the H120 group exhibited medium antibody levels, the lowest percentages of CD4⁺, CD8⁺ T lymphocytes and the highest viral loads. The 4/91 group showed the lowest antibody levels, but the highest percentages of CD4⁺, CD8⁺ T lymphocytes and the lowest viral loads. The LDT3-A group showed the highest antibody levels, the medium percentages of CD4⁺, CD8⁺ T lymphocytes and the medium viral loads. The protection rates of H120, 4/91 and LDT3-A groups were 41.7–58.3%, 75.0–83.7% and 66.7–75.0%, respectively. The present study demonstrated that the vaccines H120, 4/91 and LDT3-A could stimulate the immunized chicks to produce different levels of humoral and cellular immunity to resist the infection of IBV, but couldn’t provide complete protection against the prevalent local strains of IBV in southern China. Also, the vaccine 4/91 offered the best immune protection among the three vaccines.

Molecular prenatal diagnosis of alpha and beta thalassemia in pregnant Hakka women in southern China

BACKGROUND

To date, there has been no systematic study of DNA-based prenatal diagnosis of thalassemia in pregnant Hakka women in southern China.

METHODS

A total of 279 pregnant Hakka women with confirmed cases of thalassemia who had been treated at the Meizhou People's Hospital in China's Guangdong Province from January 2014 to December 2016 were here enrolled. Genomic DNA was extracted from peripheral blood of couples and villus, amniotic fluid, or fetal cord blood. DNA-based diagnosis was performed on the tissues of fetuses whose parents had tested positive for α- and β-globin gene mutations were found using polymerase chain reaction (PCR) and flow-through hybridization technique. Follow-up visits were performed 6 months after the fetuses were born. Prenatal diagnosis was performed on 279 fetuses in at-risk pregnancies.

RESULTS

Here, 211 α-thalassemia fetuses were confirmed, including 41 (19.43%) that tested positive for Bart's hydrops syndrome and 15 (7.11%) for Hb H disease. There were 103 (48.81%) heterozygotes. β-thalassemia was confirmed in 68 fetuses, including 23 (33.82%) with severe thalassemia and 27 (39.71%) heterozygotes. Another 12 cases were confirmed with α+β-thalassemia, including three cases of severe β-thalassemia. DNA-based testing prenatal diagnosis of thalassemia was found to be highly reliable.

CONCLUSIONS

Our findings provide key information for clinical genetic counseling of prenatal diagnosis for major thalassemia in pregnant Hakka women in southern China.

Clinical Characteristics of Juvenile Myasthenia Gravis in Southern China

Objectives

To describe the clinical profile, clinical outcomes and factors that may affect the outcome of juvenile myasthenia gravis (JMG) patients in southern China.

Methods

We reviewed information relating to JMG patients treated and evaluated at the First Affiliated Hospital, Sun Yat-sen University, between 1998 and 2015. The study involved 327 JMG patients who had been followed up for ≥1 year.

Results

Overall, 77.4% patients showed initial symptoms in the prepubertal period (<12 years). 306 patients showed only ocular symptoms at onset. By the final follow-up, 61 ocular myasthenia gravis (OMG) patients (61/306, 19.9%) had developed generalized myasthenia gravis (GMG). Anti-acetylcholine receptor antibodies (AChR-Ab) titer was an independent risk factor for generalization. Eleven patients (3.4%) experienced spontaneous remission, but four relapsed. Low-dose oral prednisone (0.25 mg/kg) was administered when symptoms did not significantly improve after pyridostigmine treatment. Immunosuppressants were administered when prednisone was unsatisfactory. Optimal outcome was achieved in 59.6% of patients. Specifically, 60 patients (18.3%) attained complete stable remission (CSR), 12 (3.7%) attained pharmaceutical remission (PR), and 123 (37.6%) attained minimal manifestation (MM). In total, 53 OMG patients (21.5%) attained CSR, a significantly higher proportion than among the GMG patients (8.6%, P = 0.009). Moreover, 67.2% of patients with duration <2 years showed significant clinical improvement compared with 46.3% of those with duration >2 years (P < 0.001). Thymectomy did not exhibit definite efficacy for JMG patients.

Conclusion

There was a low frequency of cases positive for AChR-Ab in the Chinese population. AChR-Ab titer was revealed as an independent risk factor for generalization. Low doses of prednisone could treat JMG effectively with few side effects.

Insights into the epidemic characteristics and evolutionary history of the novel porcine circovirus type 3 in southern China

Porcine circovirus type 3 (PCV3) is a newly identified circovirus from swine in the USA, China and Poland. This novel circovirus has been associated with porcine dermatitis and nephropathy syndrome (PDNS), reproductive failure and multisystemic inflammation; moreover, PCV3 poses a potential threat to the swine industry. In this retrospective study, a phylogenetic analysis was conducted to address the epidemiology and evolutionary dynamics of this novel circovirus. The total positive sample rate of PCV3 was 26.7% (76/285) and has increased gradually over the past 3 years. Of these PCV3-positive samples, 22.3% (17/76) were coinfected with PCV2. PCV3 can be detected in multiple sample types with different positive rates, and the positive rate is highest among stillborn. We also divide PCV3 into three clades (PCV3a, PCV3b and PCV3c) based on two amino acid mutations (A24V and R27K) on the cap protein in this study. In addition, the origin of PCV3 was approximately 1966 and may have originated from a bat-associated circovirus. Our results suggested that PCV3 is widely distributed in southern China and has been circulating in swine herds for nearly half a century. PCV3 has evolved into different clades caused by mutations in cap proteins; thus, further research on PCV3 epidemiology should be conducted.

A biogeographical study on tropical flora of southern China

The tropical climate in China exists in southeastern Xizang (Tibet), southwestern to southeastern Yunnan, southwestern Guangxi, southern Guangdon, southern Taiwan, and Hainan, and these southern Chinese areas contain tropical floras. I checked and synonymized native seed plants from these tropical areas in China and recognized 12,844 species of seed plants included in 2,181 genera and 227 families. In the tropical flora of southern China, the families are mainly distributed in tropical areas and extend into temperate zones and contribute to the majority of the taxa present. The genera with tropical distributions also make up the most of the total flora. In terms of geographical elements, the genera with tropical Asian distribution constitute the highest proportion, which implies tropical Asian or Indo-Malaysia affinity. Floristic composition and geographical elements are conspicuous from region to region due to different geological history and ecological environments, although floristic similarities from these regions are more than 90% and 64% at the family and generic levels, respectively, but lower than 50% at specific level. These differences in the regional floras could be influenced by historical events associated with the uplift of the Himalayas, such as the southeastward extrusion of the Indochina geoblock, clockwise rotation and southeastward movement of Lanping-Simao geoblock, and southeastward movement of Hainan Island. The similarity coefficients between the flora of southern China and those of Indochina countries are more than 96% and 80% at family and generic levels, indicating their close floristic affinity and inclusion in the same biogeographically floristic unit.