An interpretable knee replacement risk assessment system for osteoarthritis patients

Objective

Knee osteoarthritis (OA) is a complex disease with heterogeneous representations. Although it is modifiable to prevention and early treatment, there still lacks a reliable and accurate prognostic tool. Hence, we aim to develop a quantitative and self-administrable knee replacement (KR) risk stratification system for knee osteoarthritis (KOA) patients with clinical features.

Method

A total of 14 baseline features were extracted from 9592 cases in the Osteoarthritis Initiative (OAI) cohort. A survival model was constructed using the Random Survival Forests algorithm. The prediction performance was evaluated with the concordance index (C-index) and average receiver operating characteristic curve (AUC). A three-class KR risk stratification system was built to differentiate three distinct KR-free survival groups. Thereafter, Shapley Additive Explanations (SHAP) was introduced for model explanation.

Results

KR incidence was accurately predicted by the model with a C-index of 0.770 (±0.0215) and an average AUC of 0.807 (±0.0181) with 14 clinical features. Three distinct survival groups were observed from the ten-point KR risk stratification system with a four-year KR rate of 0.79%, 5.78%, and 16.2% from the low, medium, and high-risk groups respectively. KR is mainly caused by pain medication use, age, surgery history, diabetes, and a high body mass index, as revealed by SHAP.

Conclusion

A self-administrable and interpretable KR survival model was developed, underscoring a KR risk scoring system to stratify KOA patients. It will encourage regular self-assessments within the community and facilitate personalised healthcare for both primary and secondary prevention of KOA.

Mitochondria targeted biomimetic platform for chemo/photodynamic combination therapy against osteosarcoma

Clinical treatment for osteosarcoma (OS) is still lacking effective means, and no significant progress in OS treatment have been made in recent years. Single chemotherapy has serious side effects and can produce drug resistance easily, resulting poor therapeutic effect. As a modern and non-invasive treatment form, photodynamic therapy (PDT) is widely used to treat diverse cancers. Chemotherapy in combination with PDT is a particularly efficient antitumor method that could overcome the defects of monotherapies. Since mitochondria is a key subcellular organelle involved in cell apoptosis regulation, targeting tumor cells mitochondria for drug delivery has become an important entry point for anti-tumor therapy. Herein, we rationally designed a core-shell structured biomimetic nanoplatform, i.e., D@SLNP@OSM-IR780, to achieve tumor homologous targeting and mitochondria targeted drug release for chemotherapy combined with PDT against OS. Upon 808 nm laser irradiation, D@SLNP@OSM-IR780 exhibited excellent photo-cytotoxicity in vitro. The excellent targeting effect of D@SLNP@OSM-IR780 in tumor tissues produced a tumor inhibition rate of 98.9% in vivo. We further indicated that synergistic chemo-photodynamic effect induced by D@SLNP@OSM-IR780 could activate mitochondria-mediated apoptosis pathway, along with host immune response and potential photothermal effect. On the whole, D@SLNP@OSM-IR780 is revealed to be a promising platform for OS targeted combination therapeutics.

A long noncoding RNA functions in pumpkin fruit development through S-adenosyl-L-methionine synthetase

Long non-coding RNAs (lncRNAs) play important roles in various biological processes. However, the regulatory roles of lncRNAs underlying fruit development have not been extensively studied. Pumpkin (Cucurbita spp.) is a preferred model for understanding the molecular mechanisms regulating fruit development because of its variable shape and size and large inferior ovary. Here, we performed strand-specific transcriptome sequencing on pumpkin (Curcurbita maxima 'Rimu') fruits at six developmental stages and identified 5425 reliably expressed lncRNAs. Among the 332 lncRNAs that were differentially expressed during fruit development, MSTRG.44863.1 was identified as a negative regulator of pumpkin fruit development. MSTRG.44863.1 showed a relatively high expression level and an obvious period-specific expression pattern. Transient overexpression and silencing of MSTRG.44863.1 significantly increased and decreased the content of 1-aminocyclopropane carboxylic acid (a precursor of ethylene) and ethylene production, respectively. RNA pull-down and microscale thermophoresis assays further revealed that MSTRG.44863.1 can interact with S-adenosyl-L-methionine synthetase (SAMS), an enzyme in the ethylene synthesis pathway. Considering that ethylene negatively regulates fruit development, these results indicate that MSTRG.44863.1 plays an important role in the regulation of pumpkin fruit development, possibly through interacting with SAMS and affecting ethylene synthesis. Overall, our findings provide a rich resource for further study of fruit-related lncRNAs while offering insight into the regulation of fruit development in plants.

Development and validation of a nomogram and risk stratification system to predict overall survival after surgical repair for pediatric patients with medulloblastoma based on easily accessible variables

OBJECTIVE

This study aimed to develop and validate a nomogram and risk stratification system for the overall survival of pediatric patients with medulloblastoma after surgical repair.

PATIENTS AND METHODS

In this multicenter, retrospective study, consecutive patients who underwent surgery for medulloblastoma at Shanghai Children's Medical Center and the First Affiliated Hospital of Fujian Medical University from 2010 to 2022 formed the training and external validation datasets, respectively. Univariable and multivariable Cox regression analyses were performed to identify variables associated with mortality in the training dataset. A nomogram prediction model was developed based on independent variables in the multivariable Cox regression analysis to predict the 1-, 3-, and 5-year overall survival. The area under receiver operating characteristic curve (AUC) and calibration curve were used to evaluate the discrimination and calibration of the nomogram. A risk stratification system based on the median risk score was also established to divide patients into two risk groups.

RESULTS

In the training dataset, Cox regression analyses identified tumor size, brainstem involvement and chemotherapy as independent predictors for overall survival. The AUC of the nomogram was 0.75 at 1 year, 0. 75 at 3 years, 0.77 at 5 years in the training dataset, 0.74 at 1 year, 0.70 at 3 years, and 0.70 at 5 years in the validation dataset. The calibration curve for the probability of 1-, 3-, and 5-year survival showed good agreement between the nomogram prediction and actual observation in the training and validation datasets. The risk stratification system could perfectly classify patients into two risk groups, and the overall survival in the two groups had a good division.

CONCLUSIONS

This low-cost, convenient, and noninvasive nomogram can be translated into clinical practice as a tool for risk stratification and individualized prognosis prediction for children with medulloblastoma.

Biomimetic lipid nanoparticles for homologous-targeting and enhanced photodynamic therapy against glioma

Biomimetic nano-platforms have attracted extensive attention due to their good biocompatibility, low immunogenicity, and homologous targeting to lesions. In this study, glioma cell membranes are used to encapsulate indocyanine green (ICG) loaded nanoparticles (SLNP/ICG), termed as SLNP/ICG@M for targeted photodynamic therapy (PDT) against glioma. Cell membrane modification significantly enhances cellular uptake of SLNP/ICG@M in homologous glioma cells in vitro and tumor distribution in vivo. Furthermore, SLNP/ICG@M can stimulate glioma cells to generate plentiful reactive oxygen species (ROS) under NIR irradiation, finally producing excellent photo-cytotoxicity and the optimal tumor growth inhibition with a tumor suppression rate of 93.2%. We also confirm that SLNP/ICG@M combined with NIR irradiation could activate mitochondria mediated apoptosis pathway, and the increased proliferation of CD4+ T cells and CD8+ T cells accompanied by immune activation further enhances PDT effect of SLNP/ICG@M. Herein, SLNP/ICG@M is a promising biomimetic nano drug delivery system for glioma targeted PDT therapy.

McAPRR2: The Key Regulator of Domesticated Pericarp Color in Bitter Gourd

Pericarp color is a crucial commercial trait influencing consumer preferences for bitter gourds. However, until now, the gene responsible for this trait has remained unidentified. In this study, we identified a gene (McAPRR2) controlling pericarp color via a genome-wide association study (GWAS) utilizing the resequencing data of 106 bitter gourd accessions. McAPRR2 exhibits three primary haplotypes: Hap1 is a wild type with a green pericarp, Hap2 is a SA (South Asian) and SEA (Southeast Asia) type with a green pericarp, and Hap3 is primarily a SEA type with a light green pericarp. The McAPRR2 haplotype is significantly correlated with both pericarp color and ecological type. Importantly, McAPRR2 with the light green pericarp demonstrated premature termination due to a 15 bp sequence insertion. The phylogenetic tree clustered according to pericarp color and ecological type, using SNPs located in the McAPRR2 gene and its promoter. High πwild/SEA and πSA/SEA values indicate high nucleotide diversity between wild and SEA types and between SA and SEA types in the McAPRR2 gene. The haplotypes, phylogenetic tree, and nucleotide diversity of McAPRR2 suggest that McAPRR2 has undergone domestication selection. This study identifies McAPRR2 as the key gene determining pericarp color in bitter gourds and introduces a novel insight that McAPRR2 is subject to domestication selection.

First Report of Broad Bean Wilt Virus 2 Infecting Balsam (Impatiens balsamina) in China

Balsam (Impatiens balsamina L.) is an ornamental plant cultivated extensively in China and elsewhere, but it has also been used as a medicinal plant for thousands of years (Qian et al., 2023). In 2022, an examination of 10 garden-grown I. balsamina plants in Chaoyang, Beijing, China revealed eight plants with blotches, mosaic symptoms, and deformed leaves (Fig. S1A). Total RNA was extracted from the symptomatic leaf tissue of these eight plants using the TRIzol reagent (Invitrogen, USA). Four RNA preparations (high quality and quantity) were combined for the small RNA sequencing analysis (TIANGEN Biotech Co., China). A total of 16,509,586 clean reads (18-30 nt) were obtained and assembled into larger contigs using Velvet 1.0.5. A search of the National Center for Biotechnology Information non-redundant database using BLASTX indicated 72, 24, and 19 contigs were homologous to broad bean wilt virus 2 (BBWV2), cucumber mosaic virus (CMV), and impatiens cryptic virus 1 (ICV1) sequences (Zheng et al., 2022), respectively. To verify the next-generation sequencing data, the following three sets of primer pairs were designed according to the contig sequences of these three viruses: CMV-F:5'-ATGGACAAATCTGAATCAACCAGTGC-3'/CMV-R: 5'-CCGTAAGCTGGATGGACAACC-3'; BBWV2-F:5'-CAATTTGGACAACTACAATTTGCC-3'/ BBWV2-R: 5'-GCTGAGTCTAAATCCCATCTATC-3'; and ICV1-F: 5'-CGCACAACT CTACAAT GACATGGTC-3'/ICV1-R: 5'-AGTTCCATCGTCCAGTAGGCG-3'. The primers were used to amplify CMV, BBWV2, and ICV1 sequences by reverse transcription-polymerase chain reaction (RT-PCR), with individual RNA preparations serving as the template. The CMV, BBWV2, and ICV1 target sequences were amplified from eight, four, and four samples, respectively (Fig. S1B). To evaluate virus infectivity, Nicotiana benthamiana seedlings were inoculated using a leaf tissue extract prepared from an infected I. balsamina plant. At 7 days post-inoculation, disease symptoms were detected on N. benthamiana systemic leaves (e.g., deformation and apical necrosis) (Fig. S1C). Confirmation tests involving RT-PCR indicated the N. benthamiana plants were infected with BBWV2 and CMV, but not with ICV1 (Fig. S1D). To obtain the complete BBWV2 genome sequence (RNA1 and RNA2), virus-specific PCR primers (Table S1) were designed to produce the terminal sequences via 5' and 3' rapid amplification of cDNA ends (RACE), which was completed using the SMARTer RACE 5'/3' Kit (Clontech, China). The RNA1 and RNA2 sequences comprised 5,957 nt (GenBank: OQ857921) and 3,614 nt (GenBank: OQ857922), respectively. The BLAST analyses revealed RNA1 and RNA2 were similar to sequences in other BBWV2 isolates (sequence identities of 78.88% to 95.15% and 80.83% to 91.51%, respectively). Using the neighbor-joining method and MEGA 7.0, the phylogenetic relationships between the BBWV2 isolated in this study and other isolates were determined on the basis of the full-length RNA1 and RNA2 sequences (Kumar et al., 2016). According to the RNA1 and RNA2 sequences, the BBWV2 isolated in this study was most closely related to the BBWV2 isolate from Gynura procumbens (GenBank: KX686589) and the BBWV2 isolate from Nicotiana tabacum (GenBank: KX650868), respectively (Fig. S1E). To the best of our knowledge, this is the first report of I. balsamina naturally infected with BBWV2 in China. The study findings may be useful for detecting BBWV2 in I. balsamina and for diagnosing and managing the associated disease. The authors declare no conflict of interest. Yanhong Qiu and Haijun Zhang contributed equally to this paper. Funding: This research was supported by the Beijing Academy of Agriculture and Forestry Foundation, China (KYCX202305, QNJJ202131, and KJCX20230214). References: Qian H.Q., et al. 2023. J Ethnopharmacol. 303. Zheng Y., et al. 2022. Arch Virol. 167: 2099-2102. Kumar et al. 2016. Mol Biol Evol. 33: 1870-1874.

Whole-Genome Sequencing of Fusarium oxysporum f. sp. cucumerinum Strain Race-4 Infecting Cucumber in China

Fusarium oxysporum f. sp. cucumerinum, which causes root and vascular wilting, is one of the most devastating diseases infecting cucumber. Here, we report the first genome resource with high-quality assembly for F. oxysporum f. sp. cucumerinum strain Race-4, which is primarily endemic to China. The genome was 59.11 Mb in size and consisted of 48 scaffolds with an N50 of 3.87 Mb using PacBio long reads (301.77×) sequencing, and encodes 14,898 proteins from analyzing RNA-seq data. Gene annotations identified pathogen-host interaction genes, fungal virulence factors, secreted proteins, transcription factors, and secondary metabolite biosynthesis gene. Moreover, functional genes reported in previous studies were also identified in the genome of Race-4. These genes and genome resource may play important roles in understanding F. oxysporum f. sp. cucumerinum-cucumber interactions and will be useful for further research.

[Analysis of genotypes on 850 newborns with SLC26A4 single-allele mutation and the phenotypes of those with second variant]

Objective: To clarify the phenotypes of the newborns with SLC26A4 single-allele mutation in deafness genetic screening and second variant; to analyze the SLC26A4 genotype and hearing phenotype. Methods: 850 newborns born in Beijing from April 2015 to December 2019 were included and there were 468 males and 382 females. They received genetic deafness screening for 9 or 15 variants, with the result of SLC26A4 single-allele mutation. Firstly, three step deafness gene sequencing was adopted in this work, i.e., the first step was "SLC26A4 gene whole exons and splice sites" sequencing; the second step was "SLC26A4 gene promoter, FOXI1 gene and KCNJ10 gene whole exons" sequencing; and the third step was detection for "SLC26A4 gene copy number variation". Secondly, we collected the results of newborn hearing screening for all patients with the second mutation found in the three step test, and conducted audiological examinations, such as acoustic immittance, auditory brainstem response and auditory steady state response. Thirdly, for novel/VUS mutations, we searched the international deafness gene database or software, such as DVD, ClinVar and Mutation Taster, to predict the pathogenicity of mutations according to the ACMG guideline. Lastly, we analyzed the relationship between genotype and phenotype of newborns with SLC26A4 single allele mutation. Results: Among 850 cases, the median age of diagnosis was 4 months. In the first step, 850 cases were sequenced. A total of 32 cases (3.76%, 32/850) of a second variants were detected, including 18 cases (2.12%, 18/850) with identified pathogenic variants; 832 cases were sequenced and 8 cases of KCNJ10 gene missense variants were detected among the second step. No missense mutations in the FOXI1 gene and abnormal SLC26A4 gene promoter were detected; the third step sequencing results were all negative. Genotypes and hearing phenotypes included 18 cases combined with the second clear pathogenic variant, 16 cases (16/18) referred newborn hearing screening and 2 cases (2/18) passed in both ears; degree of hearing loss consisted of 18 profound ears (18/36), 13 severe ears (13/36) and 5 moderate ears (5/36); audiogram patterns comprised 17 high frequency drop ears (17/36), 14 flat ears (14/36), 3 undistinguished ears (3/36), and 2 U shaped ears (2/36); 11 cases underwent imaging examination, all of which were bilateral enlarged vestibular aqueduct. As for 22 cases of other genotypes, all passed neonatal hearing screening and the hearing diagnosis was normal, including 9 cases with VUS or possibly novel benign variants, 8 cases with KCNJ10 double gene heterozygous variants, and 5 cases with double heterozygous variants. Conclusions: The probability of individuals with SLC26A4 single-allele variant who merge with a second pathogenic variant is 2.12%, all of which are SNV, which can provide scientific basis for the genetic diagnosis and genetic counseling of SLC26A4 variants. Those who have merged with second pathogenic variant are all diagnosed with sensorineural hearing loss. Patients with KCNJ10 gene mutations do not manifest hearing loss during the infancy, suggesting the need for further follow-up.

Genetic diversity analysis and variety identification using SSR and SNP markers in melon

Melon is an important horticultural crop with a pleasant aromatic flavor and abundance of health-promoting substances. Numerous melon varieties have been cultivated worldwide in recent years, but the high number of varieties and the high similarity between them poses a major challenge for variety evaluation, discrimination, as well as innovation in breeding. Recently, simple sequence repeats (SSRs) and single nucleotide polymorphisms (SNPs), two robust molecular markers, have been utilized as a rapid and reliable method for variety identification. To elucidate the genetic structure and diversity of melon varieties, we screened out 136 perfect SSRs and 164 perfect SNPs from the resequencing data of 149 accessions, including the most representative lines worldwide. This study established the DNA fingerprint of 259 widely-cultivated melon varieties in China using Target-seq technology. All melon varieties were classified into five subgruops, including ssp. agrestis, ssp. melo, muskmelon and two subgroups of foreign individuals. Compared with ssp. melo, the ssp. agrestis varieties might be exposed to a high risk of genetic erosion due to their extremely narrow genetic background. Increasing the gene exchange between ssp. melo and ssp. agrestis is therefore necessary in the breeding procedure. In addition, analysis of the DNA fingerprints of the 259 melon varieties showed a good linear correlation (R² = 0.9722) between the SSR genotyping and SNP genotyping methods in variety identification. The pedigree analysis based on the DNA fingerprint of 'Jingyu' and 'Jingmi' series melon varieties was consistent with their breeding history. Based on the SNP index analysis, ssp. agrestis had low gene exchange with ssp. melo in chromosome 4, 7, 10, 11and 12, two specific SNP loci were verified to distinguish ssp. agrestis and ssp. melon varieties. Finally, 23 SSRs and 40 SNPs were selected as the core sets of markers for application in variety identification, which could be efficiently applied to variety authentication, variety monitoring, as well as the protection of intellectual property rights in melon.

Telomere-to-telomere genome assembly of bitter melon (Momordica charantia L. var. abbreviata Ser.) reveals fruit development, composition and ripening genetic characteristics

Momordica charantia L. var. abbreviata Ser. (Mca), known as bitter gourd or bitter melon, is a Momordica variety with medicinal value and belongs to the Cucurbitaceae family. In view of the lack of genomic information on bitter gourd and other Momordica species and to promote Mca genomic research, we assembled a 295.6-Mb telomere-to-telomere (T2T) high-quality Mca genome with six gap-free chromosomes after Hi-C correction. This genome is anchored to 11 chromosomes, which is consistent with the karyotype information, and comprises 98 contigs (N50 of 25.4 Mb) and 95 scaffolds (N50 of 25.4 Mb). The Mca genome harbors 19 895 protein-coding genes, of which 45.59% constitute predicted repeat sequences. Synteny analysis revealed variations involved in fruit quality during the divergence of bitter gourd. In addition, assay for transposase-accessible chromatin by high-throughput sequencing and metabolic analysis showed that momordicosides and other substances are characteristic of Mca fruit pulp. A combined transcriptomic and metabolomic analysis revealed the mechanisms of pigment accumulation and cucurbitacin biosynthesis in Mca fruit peels, providing fundamental molecular information for further research on Mca fruit ripening. This report provides a new genetic resource for Momordica genomic studies and contributes additional insights into Cucurbitaceae phylogeny.

Genome-Wide Identification of Powdery Mildew Responsive Long Non-Coding RNAs in Cucurbita pepo

Cucurbita pepo L. is an essential economic vegetable crop worldwide, and its production is severely affected by powdery mildew (PM). However, our understanding of the molecular mechanism of PM resistance in C. pepo is very limited. Long non-coding RNAs (lncRNAs) play an important role in regulating plant responses to biotic stress. Here, we systematically identified 2,363 reliably expressed lncRNAs from the leaves of PM-susceptible (PS) and PM-resistant (PR) C. pepo. The C. pepo lncRNAs are shorter in length and expressed at a lower level than the protein-coding transcripts. Among the 2,363 lncRNAs, a total of 113 and 146 PM-responsive lncRNAs were identified in PS and PR, respectively. Six PM-responsive lncRNAs were predicted as potential precursors of microRNAs (miRNAs). In addition, 58 PM-responsive lncRNAs were predicted as targets of miRNAs and one PM-responsive lncRNA was predicted as an endogenous target mimic (eTM). Furthermore, a total of 5,200 potential cis target genes and 5,625 potential trans target genes were predicted for PM-responsive lncRNAs. Functional enrichment analysis showed that these potential target genes are involved in different biological processes, such as the plant-pathogen interaction pathway, MAPK signaling pathway, and plant hormone signal transduction pathway. Taken together, this study provides a comprehensive view of C. pepo lncRNAs and explores the putative functions of PM-responsive lncRNAs, thus laying the foundation for further study of the regulatory mechanisms of lncRNAs responding to PM.

First report of tomato spotted wilt virus infecting water dropwort in China

Water dropwort (Oenanthe javanica) is an aquatic perennial plant that has been cultivated in many regions in Asia for thousands of years. In China, it is an economically important vegetable that has been consumed as food, while also being used as a folk remedy to alleviate diseases (Liu et al., 2021). In 2021, during a disease survey of a greenhouse in Beijing, China, chlorotic spots were detected on many water dropwort plants (Fig. S1A). Twenty-seven water dropwort samples were collected for the extraction of total RNA using the TRIzol reagent (Invitrogen, USA). High-quality RNA samples from three water dropwort plants were combined and used as the template for constructing a single small RNA library (BGI-Shenzhen Company, China). The Velvet 1.0.5 software was used to assemble the clean reads (18 to 28 nt) into larger contigs, which were then compared with the nucleotide sequences in the National Center database using the BLASTn algorithm. Thirty-eight contigs matched sequences in the tomato spotted wilt virus (TSWV) genome. No other viruses were detected. Twenty-seven leaf samples were analyzed in an enzyme-linked immunosorbent assay (ELISA) with anti-TSWV antibody (Agdia, USA), which revealed 17 positive reaction. Two sets of primer pairs targeting different parts of the S RNA (Table S1) was used to verify the TSWV infection on water dropwort by reverse transcription (RT)-PCR followed by Sanger sequencing (BGI-Shenzhen, China). The TSWV target sequences were amplified from 17 samples, which was consistent with the ELISA results. The sequenced 861-bp PCR product shared 99.8% nucleotide sequence identity with TSWV isolate MR-01 (MG593199), while the 441-bp amplicon shared a 99.2% nucleotide sequence identity with MR-01 (MG593199). To obtain the whole genome sequence of TSWV (S, M, and L RNA sequences), specific RT-PCR primers were designed (Table S1) and used to amplify their respective fragments from one representative sample (TSWV-water dropwort). The amplified products were inserted into PCE2TA/Blunt-Zero vector (Vazyme Biotech Co., Ltd, China) and then sequenced (BGI-Shenzhen, China). The S, M, and L RNA sequences were determined to be 2,952 nt (accession no. OM154969), 4,776 nt (accession no. OM154970), and 8,914 nt (accession no. OM154971), respectively. BLASTn analysis demonstrated that the whole genome sequence was highly conserved. The nucleotide identities between this isolate and other TSWV isolates ranged from 98.6% to 99.6% (S RNA), 98.9% to 99.2% (M RNA), and 97.3% to 98.7% (L RNA). Using MEGA 7.0, the phylogenetic relationships of TSWV were determined on the basis of the S, M, and L RNA full-length sequences (Kumar et al., 2016). In the S RNA derived phylogenetic tree, the water dropwort isolate was closely related to the MR-01 isolate from the USA (MG593199). In the M RNA and L RNA derived phylogenetic trees, the water dropwort isolate formed a branch with only a TSWV isolate from eggplant. Additionally, the M and L RNA sequences were most similar to sequences in TSWV isolates from China and Korea, respectively (Fig. S1B). To the best of our knowledge, this is the first report of water dropwort as a natural host for TSWV in China and the second report worldwide since the first finding in the Korea (Kil et al. 2020). TSWV has caused serious problems on many crops in the world, and the infection of TSWV on water dropwort in a greenhouse should not be looked lightly. Firstly, the virus can be passed on from generation to generation in infected water dropwort due to the vegetative propagation mode of the plant in production, thus threaten the production of this vegetable crop. In addition, infected water dropwort may serve as a reservoir for the virus, thus potentially posing a threat for causing TSWV spread in the affected greenhouses. The author(s) declare no conflict of interest. Funding: This research was supported by the Beijing Academy of Agriculture and Forestry Foundation, China (QNJJ202131, KJCX20200212, and KJCX20200113). References: Kil et al. 2020. Plant Pathol. J. 36: 67-75 Kumar et al. 2016. Mol Biol Evol, 33: 1870-1874 Liu et al. 2021. Horticulture Research. 8:1-17.

[Clinical features of children with Cunninghamella spp. infection: a case report and literature review]

We report a case of mucormycosis induced by Cunninghamella spp. infection in a ten-year-old girl with acute lymphoblastic leukemia, who developed fever and respiratory symptoms after chemotherapy and was diagnosed with invasive fungal disease. Peripheral blood DNA sequences were analyzed using metagenomic next-generation sequencing (mNGS), and by comparison with the Pathogens Metagenomics Database (PMDB), we identified Cunninghamella spp. with sequence number 514 as the pathogen. The patient was treated with amphotericin B combined with posaconazole and showed a favorable response. We searched Pubmed, Embase, CNKI, and Wanfang database for reports of cases of Cunninghamella spp. infection in children and retrieved 22 reported cases (including 12 males) with a median age of 13.5 (3-18) years. In these 22 cases, hematological malignancy was the most common underlying condition (19/22), and most of patients experienced an acute onset and rapid progression with respiratory symptoms (14/20) and fever (16/20) as the most common symptoms. CT imaging often showed unilateral lesions with varying imaging findings, including pulmonary nodules or masses, infiltrative changes, and pleural effusion. Definite diagnoses were established in 18 of the cases, and 4 had probable diagnoses; the lungs and skin were the most frequent organs compromised by the infection. A definite diagnosis of Cunninghamella spp. infection still relied on histopathological examination and fungal culture, but the molecular techniques including PCR and mNGS had shown potentials in the diagnosis. Almost all the cases received antifungal treatment after diagnosis (21/22), and 13 patients also underwent surgeries. Death occurred in 9 (42%) of the cases at a median of 19 (4-54) days after onset of the signs or symptoms. The patients receiving antifungal therapy combined with surgery had a high survival rate (9/13, 69%) than those with antifungal therapy alone (3/8, 37%). Invasive fungal disease is a common complication in immunoco-mpromised patients, but Cunninghamella spp. infection is rare and has a high mortality rate. In cases highly suspected of this disease, active diagnosis and early treatment are critical to improve the survival outcomes of the patients.

The vegetable SNP database: An integrated resource for plant breeders and scientists

Single nucleotide polymorphisms (SNPs) are widely used in genetic research and molecular breeding. To date, the genomes of many vegetable crops have been assembled, and hundreds of core germplasms for each vegetable have been sequenced. However, these data are not currently easily accessible because they are stored on different public databases. Therefore, a vegetable crop SNP database should be developed that hosts SNPs demonstrated to have a high success rate in genotyping for genetic research (herein, "alpha SNPs"). We constructed a database (VegSNPDB, http://www.vegsnpdb.cn/) containing the sequence data of 2032 germplasms from 16 vegetable crop species. VegSNPDB hosts 118,725,944 SNPs of which 4,877,305 were alpha SNPs. SNPs can be searched by chromosome number, position, SNP type, genetic population, or specific individuals, as well as the values of MAF, PIC, and heterozygosity. We hope that VegSNPDB will become an important SNP database for the vegetable research community.

Dual RNA-seq Reveals the Global Transcriptome Dynamics of Ralstonia solanacearum and Pepper (Capsicum annuum) Hypocotyls During Bacterial Wilt Pathogenesis

Bacterial wilt, caused by Ralstonia solanacearum, is a serious disease in pepper. However, the interaction between the pathogen and pepper remains largely unknown. This study aimed to gain insights into determinants of pepper susceptibility and R. solanacearum pathogenesis. We assembled the complete genome of R. solanacearum strain Rs-SY1 and identified 5,106 predicted genes, including 84 type III effectors (T3E). RNA-seq was used to identify differentially expressed genes (DEGs) in susceptible pepper CM334 at 1 and 5 days postinoculation (dpi) with R. solanacearum. Dual RNA-seq was used to simultaneously capture transcriptome changes in the host and pathogen at 3 and 7 dpi. A total of 1,400, 3,335, 2,878, and 4,484 DEGs of pepper (PDEGs) were identified in the CM334 hypocotyls at 1, 3, 5, and 7 dpi, respectively. Functional enrichment of the PDEGs suggests that inducing ethylene production, suppression of photosynthesis, downregulation of polysaccharide metabolism, and weakening of cell wall defenses may contribute to successful infection by R. solanacearum. When comparing in planta and nutrient agar growth of the R. solanacearum, 218 and 1,042 DEGs of R. solanacearum (RDEGs) were detected at 3 and 7 dpi, respectively. Additional analysis of the RDEGs suggested that enhanced starch and sucrose metabolism, and upregulation of virulence factors may promote R. solanacearum colonization. Strikingly, 26 R. solanacearum genes were found to have similar DEG patterns during a variety of host-R. solanacearum interactions. This study provides a foundation for a better understanding of the transcriptional changes during pepper-R. solanacearum interactions and will aid in the discovery of potential susceptibility and virulence factors.

First report of squash leaf curl China virus infecting tomato in China

Squash leaf curl China virus (SLCCNV) is a species in the genus Begomovirus that possess a bipartite genome. It is transmitted by the whitefly species Bemisia tabaci and infects cucurbit crops in various parts of the Old World (Wu et al., 2020). In 2020, tomato plants with curled, distorted and yellow leaves were found in a greenhouse in Shouguang, Shandong Province, China (Fig. S1). Leaves with these symptoms were collected from 11 plants and the total RNA was extracted with TRIzol reagent (Invitrogen, USA). Five RNA extracts of the highest quality were combined and a small RNA library was generated by the company (BGI-Shenzhen, China). About 22,338,920 clean reads (18-28nt) were acquired and assembled into larger contigs with the software Velvet 1.0.5. These were further compared against nucleotide sequences in the National Center for Biotechnology Information (NCBI) databases with BLASTn searches. Not unexpectedly, there were many assembled contigs that had high identities (90%-100% identities) with known tomato-infecting viruses, including 241 contigs matching tomato chlorosis virus, 26 contigs matching southern tomato virus, and 4 contigs matching tomato yellow leaf curl virus. However, 12 contigs had high identities (90%-100%) with the genomic DNA-A of SLCCNV, while 9 other contigs had high identities (90%-100%) with the genomic DNA-B of SLCCNV. To verify the presence of SLCCNV in tomato plants, two sets of primer pairs were designed according to the specific contigs assembled from derived small interfering RNAs (vsiRNAs). The primer pairs A742-F/A742-R (5'-GTAATACGAGCATCCGCACGGTAG-3'/5'-CGTGGAGGGCGAC AAACAGCTAACG-3') and B539-F/B539-R (5'-GCTACTTTCAAGGACGAAGAAGAGG-3'/5'-CG ACATAGATTTCTGGTCGGTGGGC-3') directed the amplification of 742 bp and 539 bp for DNA-A and DNA-B fragments, respectively, from the total genomic DNA of the 11 tomato samples. The DNA-A and DNA-B of SLCCNV were both detected from all of the tomato samples. After sequencing, the 742 bp PCR products shared 100% nucleotide sequence identity with the DNA-A of SLCCNV isolate GDXW (MW389919), whereas the PCR-amplified 539 bp fragments shared 100% nucleotide sequence identity with the DNA-B of SLCCNV isolate GDXW (MW389920). The full-length of DNA-A and DNA-B components were amplified with back-to-back primers A-F/A-R (Wu et al., 2020) and B-F/B-R (5'-GATAAACACGTCTCATTGCACCGC-3'/5'-GAGACGTGTTTATCAATATGGA CG-3'), respectively. The amplified fragments were further cloned into the PCE2TA/Blunt-Zero vector (Vazyme Biotech Co., China). After sequencing, the complete sequence of DNA-A was 2736 nt in length (MZ682117), while the DNA-B was 2718 nt in length (OK236348). The phylogenetic relationships of the DNA-A and DNA-B components were determined using MEGA 7 based on the full-length sequences of DNA-A and DNA-B, respectively (Kumar et al., 2016). Results showed that the DNA-A formed an independent cluster and was mostly related to the GDHY (MW389917) in the phylogenetic tree constructed using the neighbor-joining (NJ) method, while the DNA-B formed an independent cluster and was mostly related to the SLCCNV isolate BLDG (MW389928) and isolate GDBL (MW389922) (Fig. S2). The nt identities of DNA-A were also calculated with SDT v1.2 by comparison with other begomovirus sequences from the initial BLASTn analysis (Muhire et al., 2014), showing that the virus shared 99.4% sequence identity with SLCCNV isolate GDHY (MW389917). According to the current demarcation threshold for begomoviruses, recommended by the International Committee on Taxonomy of Viruses (ICTV) (91% nt identity) (Brown et al., 2015), this virus identified from tomato is a distinct strain of SLCCNV, designated SLCCNV-SDSG. To the best of our knowledge, this is the first report of a natural infection of SLCCNV on tomato in China. SLCCNV has caused serious problems in cucurbit production in some areas, so it will be important to investigate if tomato plays a role in the disease biology by serving as a reservoir host. The author(s) declare no conflict of interest. Funding: The funding for this research was supported by the Beijing Academy of Agriculture and Forestry Foundation, China (QNJJ202131, QNJJ201915, KJCX20200113). References: Brown et al. 2015. Arch Virol 160: 1593-1619 Kumar et al. 2016. Mol Biol Evol, 33: 1870-1874 Muhire et al. 2014. Plos One, 9 Wu et al. 2020. J Integr Agr, 19: 570-577.

Cucurbitaceae genome evolution, gene function and molecular breeding

The Cucurbitaceae is one of the most genetically diverse plant families in the world. Many of them are important vegetables or medicinal plants and are widely distributed worldwide. The rapid development of sequencing technologies and bioinformatic algorithms has enabled the generation of genome sequences of numerous important Cucurbitaceae species. This has greatly facilitated research on gene identification, genome evolution, genetic variation and molecular breeding of cucurbit crops. So far, genome sequences of 18 different cucurbit species belonging to tribes Benincaseae, Cucurbiteae, Sicyoeae, Momordiceae and Siraitieae have been deciphered. This review summarizes the genome sequence information, evolutionary relationship, and functional genes associated with important agronomic traits (e.g., fruit quality). The progress of molecular breeding in cucurbit crops and prospects for future applications of Cucurbitaceae genome information are also discussed.

Dietary chitooligosaccharide supplementation alleviates intestinal barrier damage, and oxidative and immunological stress in lipopolysaccharide-challenged laying hens

This study aimed to investigate the effects of chitooligosaccharide (COS) on intestinal barrier, antioxidant capacity, and immunity of lipopolysaccharide (LPS)-challenged laying hens. A total of 360 Hy-line Brown laying hens (80-wk-old) were randomly divided into 5 groups with 6 replicates of 12 birds. Hens were fed a corn-soybean meal basal diet supplemented with different COS levels (0; 5; 10; 15; 20 mg/kg) for 8 wk. The results showed that 15 mg/kg COS administration elevated albumen height and Haugh unit (P < 0.05), and numerically optimized productive performance (P > 0.05), therefore, the dosage of 15 mg/kg was chosen for the subsequent experiment. Thereafter, 12 birds from non-supplemented group were randomly selected and assigned into 2 groups, and birds in each group were administered (1.5 mg/kg BW, i.p.) with saline (control group) or LPS (challenge group). Another 6 hens from 15 mg/kg COS-supplemented group were selected and injected with LPS in the same way. Compared with the control group, LPS-challenged birds exhibited elevated circulating diamine oxidase activity, and reduced jejunal villus height and ratio of villus height to crypt depth, and these indices were reversed to control levels by COS (P < 0.05). Also, LPS increased malondialdehyde accumulation and reduced several antioxidant enzyme activities in the intestinal mucosa (P < 0.05). Additionally, LPS increased jejunal secretory IgA and interferon-γ (IFN-γ), and ileal secretory IgA, IgM, and interleukin-1β (IL-1β) concentrations, whereas COS reduced jejunal IFN-γ and IL-1β, and ileal IgM levels (P < 0.05). Moreover, LPS down-regulated mRNA abundance of jejunal occludin and claudin 2, and upregulated expression of jejunal nuclear factor erythroid-2 related factor 2, superoxide dismutase 1, and IFN-γ as well as ileal IL-1β (P < 0.05). Besides, COS increased jejunal occludin and ileal claudin 2, nuclear factor erythroid-2 related factor 2, and heme oxygenase-1 expression, and decreased jejunal IFN-γ and IL-1β abundance (P < 0.05). These results suggested that COS could alleviate LPS-induced intestinal barrier impairment, and oxidative and immunological stress in laying hens.

[Analysis of epidemiological characteristics of human coronavirus in hospitalized children with respiratory tract infection in Hebei region]

Objective: To investigate the epidemiological characteristics of human coronavirus (HCoV) in hospitalized children with respiratory tract infection in Hebei region, providing evidence for the diagnosis and prevention of children with respiratory tract infection. Methods: A retrospective study was conducted on 1 062 HCoV positive children hospitalized for respiratory tract infection in Children's Hospital of Hebei Province from January 2015 to December 2020, aged from 33 days to 14 years, with a median age of 2 years. 27 932 (60.9%) were males and 17 944(39.1%) were females. And the gender, ages, seasonal distribution, HCoV-positive rates, co-detection distribution and clinical diagnosis of HCoV positive cases were analyzed by SPSS 25.0. Enumeration data were expressed by frequency and percentage; categorical variable were compared by the Pearson χ²test. Results: The overall HCoV-positive rate was 2.31% (1 062/45 876), which was 2.37% (662/27 932) in male children and 2.23% (400/17 944) in female children. There was no statistically significant difference between genders (χ²=0.916, P=0.339). Children at age groups<1 years (2.44%) and 1-<3 years (2.63%) had higher HCoV-positive rates than those at age groups 3-<5 years (1.97%) and ≥5 years (1.38%) (χ²=27.332,P<0.01). The HCoV-positive rates from 2015 to 2018 were 2.13%, 2.45%, 2.28% and 2.23%. The HCoV-positive rate of 2019 (1.71%) was significantly lower than in 2016 (χ²=12.05, P<0.01), 2017 (χ²=7.34, P=0.01) and 2018 (χ²=6.78, P=0.01), but there was no significant difference compared with 2015 (χ²=2.84, P=0.09). The HCoV-positive rate of 2020 (3.37%) was significantly higher than in 2015 (χ²=13.636, P<0.01), 2016 (χ²=11.099, P<0.01), 2017 (χ²=15.482, P<0.01), 2018(χ²=18.601, P<0.01) and 2019(χ²=45.580, P<0.01). The positive rate was highest in spring (March to May) in 2015 and 2017 to 2018. February to April and July to September of 2016 were the peak periods of positive detection. No obvious seasonal change was observed in 2019 and the HCoV-positive rate of 2020 was extremely low from January to July, following significantly increased from August to December. 26.37% (280/1 062) of HCoV were co-detected with other respiratory pathogens and the most frequently identified mixed detection was RSV. Three or more pathogens were detected in 7.34% (78/1 062) of the HCoV-positive samples. Bronchopneumonia and bronchiolitis were more frequently observed in the single HCoV positive (61.89% and 16.75%) children compared to co-detected children(34.29% and 9.64%)(χ²=63.394 and 8.228, P<0.01). However, compared to those with HCoV mono-detection, co-detected children were more likely to have severe pneumonia (4.6% and 47.14%) (χ²=280.171, P<0.01). Conclusions: HCoV is one of the respiratory pathogens in children in Hebei region and more prevalent in spring. The susceptible population of HCoV is mainly children under the age of 3 years old. HCoV often co-detects with other respiratory pathogens, and the co-infection is one of the risk factors of severe pneumonia in children with respiratory infection.

Age-related changes in liver metabolism and antioxidant capacity of laying hens

This study aimed to investigate the age-related changes of hepatic metabolism and antioxidant capacity of laying hens at 3 different ages. A total of 192 Hy-line Brown laying hens were assigned into 3 groups: 1) 195-day-old (D195 group); 2) 340-day-old (D340 group); 3) 525-day-old (D525 group). Each group replicated 8 times with 8 hens at the same age. Higher activity of aspartate aminotransferase and lower contents of total protein and globulin were observed in the serum of 525-day-old hens in comparison with their 195-day-old counterparts (P < 0.05). The 525-day-old hens accumulated higher contents of total cholesterol and triglyceride in the liver than 195-day-old birds. Additionally, compared with hens from D195 or D340 group, 525-day-old birds exhibited a lower circulating estradiol level (P < 0.05). For antioxidant capacity, birds in the D525 group showed a higher malondialdehyde concentration in both serum and liver as compared with D195 or D340 group (P < 0.05). The 525-day-old hens also exhibited lower glutathione peroxidase activities in both serum and liver when compared with 195-day-old birds (P < 0.05). Simultaneously, there was a decline of hepatic superoxide dismutase activity in the D525 group in comparison with D195 group (P < 0.05). Compared with 195-day-old counterparts, 340-day-old birds upregulated the mRNA abundance of nuclear factor erythroid-2 related factor 2 and glutathione peroxidase 1 in the liver (P < 0.05). In contrast, hens from D525 group showed the downregulation of hepatic nuclear factor erythroid-2 related factor 2, NAD(P)H quinone dehydrogenase 1, and superoxide dismutase 1 when compared with D340 group (P < 0.05). These results indicated that increasing age can adversely affect liver metabolism and function of laying hens.

The cholinergic system in joint health and osteoarthritis: a narrative-review

Osteoarthritis (OA) poses a major health and economic burden worldwide due to an increasing number of patients and the unavailability of disease-modifying drugs. In this review, the latest understanding of the involvement of the cholinergic system in joint homeostasis and OA will be outlined. First of all, the current evidence on the presence of the cholinergic system in the normal and OA joint will be described. Cholinergic innervation as well as the non-neuronal cholinergic system are detected. In a variety of inflammatory diseases, the classic cholinergic anti-inflammatory pathway lately received a lot of attention as via this pathway cholinergic agonists can reduce inflammation. The role of this cholinergic anti-inflammatory pathway in the context of OA will be discussed. Activation of this pathway improved the progression of the disease. Secondly, chondrocyte hypertrophy plays a pivotal role in osteophyte formation and OA development; the impact of the cholinergic system on hypertrophic chondroblasts and endochondral ossification will be evaluated. Cholinergic stimulation increased chondrocyte proliferation, delayed chondrocyte differentiation and caused early mineralisation. Moreover, acetylcholinesterase and butyrylcholinesterase affect the endochondral ossification via an acetylcholine-independent pathway. Thirdly, subchondral bone is critical for cartilage homeostasis and metabolism; the cholinergic system in subchondral bone homeostasis and disorders will be explored. An increase in osteoblast proliferation and osteoclast apoptosis is observed. Lastly, current therapeutic strategies for OA are limited to symptom relief; here the impact of smoking on disease progression and the potential of acetylcholinesterase inhibitors as candidate disease-modifying drug for OA will be discussed.

[Effects of vestibular spontaneous nystagmus on visual smooth pursuit function]

Objective: The aim of the study is to analyze the effects of vestibular spontaneous nystagmus(SN) on the smooth pursuit function of visual ocularmotor system. Methods: A total of 46 patients with acute unilateral peripheral vestibular syndrome with SN (26 cases of vestibular neuritis, 6 cases of Ramsay Hunt Syndrome (RHS) with vertigo, 14 cases of sudden deafness with vertigo) were included in this work. In the study group, the results of SPT and SN test with videonystagmography(VNG) were also reviewed. Taking SPT parameters, the influence of SN intensity on SPT gain, asymmetry and waveform and their correlation were analyzed.SPSS19.0 software was used for statistical analysis. Results: Among the 46 patients, there were 36 cases of SN pointing to the healthy side(SN intensity range of 2.68°/s-32.53°/s), and 10 cases of SN pointing to the affected side (SN intensity range of 2.66°/s-16.54°/s). SN intensity was divided into 3 groups, including light(0.50°/s-5.00°/s), medium(5.01°/s-10.00°/s) and strong(>10.01°/s), accounting for 14 cases(30.4%), 18 cases(39.1%) and 14 cases(30.4%), respectively. The differences of the gain of SPT to the fast phase and slow phase direction in the overall groups and light, medium and strong groups of SN intensity respectively were statistically significant(t_total=13.338, t_light=6.184, t_medium=8.436, t_strong=8.477, all of P<0.001). The difference of SPT gain in SN fast phase direction between groups with different SN intensity was statistically significant(F=9.639, P<0.001),there was no statistically significant difference in SPT gain between the groups on the SN slow phase direction(F=1.137, P=0.330).The SN intensity significantly negatively correlated with the SPT gain of the fast phase direction of SN (r=-0.433, P=0.003), that was, the SPT gain on the fast phase direction of SN decreased with the increase of SN intensity. There was no significant correlation between SN intensity and the gain of SPT on the slow phase direction of SN (r=-0.061, P=0.687). SPT waveform analysis showed that type I, type II and type III accounted for 8 cases(17.4%), 21 cases(45.6%) and 17 cases(37.0%), respectively. The corresponding mean values of SN intensity were (3.71±0.69)°/s, (7.44±1.88)°/s, (20.04±5.53)°/s, respectively, without type IV wave. The intensity of SN was positively correlated with the asymmetric value of the gain of SPT left and right(r=0.450,P=0.002). That was, with the increase of SN strength, the asymmetric value also increased, and the worse the asymmetry of the gain of SPT left and right pursuit was, the worse the SPT waveform was. Conclusion: SPT gain, asymmetry and SPT waveforms are all affected by SN, and the greater the intensity of SN, the greater the influence on the three. When SN is strong, type III waves may occur, suggesting that acute peripheral vestibular syndrome can also affect the visual ocularmotor systems.

A comparison of intestinal integrity, digestive function, and egg quality in laying hens with different ages

Intestinal integrity, digestive enzyme activity, nutrient utilization, and egg quality of laying hens at different ages were evaluated and compared in this study. A total of 192 Hy-line Brown laying hens at 195-d-old (D195 group), 340-d-old (D340 group), and 525-d-old (D525 group) were allocated into one of 3 groups in accordance with their ages. Each group had 8 replicates of 8 birds each, and all birds were fed a maize-soybean meal basal diet for a 2-wk experiment. Compared with the D195 group, intestinal villus height and ratio of villus height to crypt depth, as well as serum D-lactate content increased in the D525 group (P < 0.05). The sucrase and maltase activities in the jejunal mucosa, amylase activity in the pancreas, and trypsin activity in the jejunal chyme of 525-d-old hens were lower than their 195-d-old counterparts (P < 0.05). In addition, there was a decline of trypsin and lipase activities in the ileal chyme of hens from D525 group in comparison with D195 or D340 group (P < 0.05). Apparent retention of dry matter and crude protein of birds in D340 and D525 group decreased when compared with the D195 group (P < 0.05). Moreover, birds in the D525 group exhibited a lower level of ether extract retention, and higher contents of several excreted amino acids than those in the D195 group (P < 0.05). Compared with the D195 group, eggs harvested from D525 group exhibited lower albumen height, eggshell strength and thickness, and a higher egg weight (P < 0.05). In conclusion, increased intestinal permeability (higher serum D-lactate content), compromised digestive function (lower digestive enzyme activities and apparent nutrient retention, and higher concentrations of excreted amino acids), and poor egg quality (lower albumen height, eggshell strength, and thickness) were observed with increasing age in the laying hens.

[Cytotoxic effect of photodynamic liposome gel combined with trastuzumab on drugresistant breast cancer cells in vitro]

OBJECTIVE

To evaluate the cytotoxic effect of photodynamic therapy (PDT) combined with targeted therapy using cross-linked liposomes and gels (Ce6-PC-Tmab@A-Gel) loaded with photosensitizer Chlorin (Ce6) and the tumor-targeting drug Trastuzumab (Tmab) in drug-resistant HER2+ breast cancer cells.

OBJECTIVE

Ce6-PC-Tmab liposomes were prepared using the thin-film hydration method. The general properties, encapsulation efficiency and near-infrared responsivity of the nanoparticles were evaluated. Ce6-PC-Tmab@A-Gel with a shear response was prepared by freeze drying and stirring crosslinking, and its microstructure was observed with scanning electron microscopy (SEM) and the shear response evaluated using a rheometer. The inhibitory effect of Ce6-PC-Tmab@A-Gel in drug-resistant HER2⁺ breast cancer SK-BR-3 cells was assessed with cytotoxicity assay (MTT assay) combined with near-infrared light.

OBJECTIVE

The particle size of Ce6-PC-Tmab was 239.7±9.7 nm and the potential was -2.03±0.09 mV. The entrapment efficiency of Tmab by Ce6-PC-Tmab liposomes was (40.22± 0.73)%. The prepared Ce6-PC-Tmab@A-Gel had a good shear response with excellent drug release characteristics under nearinfrared light, and increased intensity and duration of near-infrared light exposure enhanced Tmab release from the gel. Ce6-PC-Tmab@A-Gel was stable at room temperature and in a simulated tumor microenvironment (pH 6.25). Cytotoxicity assay (MTT) showed that Ce6-PC-Tmab@A-Gel combined with near-infrared light resulted in a survival rate of (31.37±1.73)% in SKBR-3 cells, much lower than that in the control group and other treatment groups (P < 0.01); the combined treatment also had a high efficiency of ROS production, and ROS release reached (22.36 ± 0.11)% after 2 min of near-infrared light exposure.

OBJECTIVE

The prepared Ce6-PC-Tmab@A-Gel has good near-infrared light response release characteristics to ensure effective targeted therapy with Tmab. The injectable gel system potentially allows long-term local drug release in the tumor to improve the treatment efficacy against drug-resistant breast cancer.

Combined genomic, transcriptomic, and metabolomic analyses provide insights into chayote (Sechium edule) evolution and fruit development

Chayote (Sechium edule) is an agricultural crop in the Cucurbitaceae family that is rich in bioactive components. To enhance genetic research on chayote, we used Nanopore third-generation sequencing combined with Hi-C data to assemble a draft chayote genome. A chromosome-level assembly anchored on 14 chromosomes (N50 contig and scaffold sizes of 8.40 and 46.56 Mb, respectively) estimated the genome size as 606.42 Mb, which is large for the Cucurbitaceae, with 65.94% (401.08 Mb) of the genome comprising repetitive sequences; 28,237 protein-coding genes were predicted. Comparative genome analysis indicated that chayote and snake gourd diverged from sponge gourd and that a whole-genome duplication (WGD) event occurred in chayote at 25 ± 4 Mya. Transcriptional and metabolic analysis revealed genes involved in fruit texture, pigment, flavor, flavonoids, antioxidants, and plant hormones during chayote fruit development. The analysis of the genome, transcriptome, and metabolome provides insights into chayote evolution and lays the groundwork for future research on fruit and tuber development and genetic improvements in chayote.

Correction of the Tear Trough Deformity and Concomitant Infraorbital Hollows With Extracellular Matrix/Stromal Vascular Fraction Gel

BACKGROUND

The tear trough deformity is a sign of eye aging. Filling is an ideal choice for the tear trough accompanied by infraorbital hollows.

OBJECTIVE

To evaluate the efficacy and safety of stromal vascular fraction gel (SVF-gel) as a filler for the tear trough deformity which is combined with infraorbital hollows.

MATERIALS AND METHODS

From July 2017 to June 2018, 33 patients underwent autologous fat aspiration and were followed up successfully. Stromal vascular fraction gel was used to correct patients with bilateral Barton I/II; tear trough deformity and infraorbital hollows. Improvement was evaluated by measuring skin-periosteal depth, 3D volume, global aesthetic improvement scale (GAIS), and patient self-assessment.

RESULTS

Skin-periosteal depth improved significantly (p < .001). The volumetric increment of the tear trough and infraorbital regions increased 2.132 ± 0.671 mL, and the retention rate was excellent (72.87 ± 10.23%). The GAIS showed a high score (2.5 ± 0.5 points), with patient self-assessment showing satisfactory results for all 7 questions on the questionnaire.

CONCLUSION

The high retention rate of SVF-gel suggests that it can provide an effective solution to tear trough deformity accompanied by infraorbital hollows.

Endothelin-1 induces chondrocyte senescence and cartilage damage via endothelin receptor type B in a post-traumatic osteoarthritis mouse model

OBJECTIVES

This study aimed to investigate the role of endothelin-1 (ET-1), originally known as the potent vasoconstrictor, and its receptors in chondrocyte senescence and osteoarthritis (OA) development.

METHOD

Temporal changes of ET-1 and its receptors with OA development were characterized in a posttraumatic OA (PTOA) mouse model at time zero, 1-month and 4-month after surgical induction via destabilization of medial meniscus (DMM). A transgenic ET-1 overexpression (TET-1) mouse model was deployed to assess the impact of upregulated ET-1 on chondrocyte senescence and cartilage degradation. Effects of endothelin receptor blockade on chondrocyte senescence and OA development were further examined both in vitro and in vivo.

RESULTS

Local expression of ET-1 in subchondral bone and synovium upregulated after DMM with an increase of plasma ET-1 level from 3.18 ± 0.21 pg/ml at time zero to 6.47 ± 0.34 pg/ml at 4-month post-surgery. Meanwhile, endothelin type B receptor (ET_BR) (53.31 ± 2.42% to 83.8 ± 2.65%) and p16^INK4a (10.91 ± 1.07% to 28.2 ± 1.0%) positve chondrocytes accumulated in articular cartilage since 1-month prior to cartilage loss at 4-month post-surgery. Overexpressed ET-1 promoted p16^INK4a-positive senescent chondrocytes accumulation and cartilage degradation in TET-1 mice. Selective blockade of ET_BR, but not ET_AR, lowered the expression of p16^INK4a in ET-1 or H₂O₂-induced chondrocyte senescence model, and mitigated the severity of murine PTOA. Intriguingly, reactive oxygen species (ROS) scavenger, Vitamin C, could rescue ET-1-induced chondrocyte senescence in vitro associated with restoration of mitochondrial dynamics.

CONCLUSION

ET-1 could induce chondrocytes senescence and cartilage damages via ET_BR in PTOA.

The genome and transcriptome analysis of snake gourd provide insights into its evolution and fruit development and ripening

Snake gourd (Trichosanthes anguina L.), which belongs to the Cucurbitaceae family, is a popular ornamental and food crop species with medicinal value and is grown in many parts of the world. Although progress has been made in its genetic improvement, the organization, composition, and evolution of the snake gourd genome remain largely unknown. Here, we report a high-quality genome assembly for snake gourd, comprising 202 contigs, with a total size of 919.8 Mb and an N50 size of 20.1 Mb. These findings indicate that snake gourd has one of the largest genomes of Cucurbitaceae species sequenced to date. The snake gourd genome assembly harbors 22,874 protein-coding genes and 80.0% of the genome consists of repetitive sequences. Phylogenetic analysis reveals that snake gourd is closely related to sponge gourd but diverged from their common ancestor ~33-47 million years ago. The genome sequence reported here serves as a valuable resource for snake gourd genetic research and comparative genomic studies in Cucurbitaceae and other plant species. In addition, fruit transcriptome analysis reveals the candidate genes related to quality traits during snake gourd fruit development and provides a basis for future research on snake gourd fruit development and ripening at the transcript level.

Effect of Laser Shock Peening on Fretting Fatigue Life of TC11 Titanium Alloy

The purpose of this paper is to investigate the performance of laser shock peening (LSP) subjected to fretting fatigue with TC11 titanium alloy specimens and pads. Three laser power densities (3.2 GW/cm², 4.8 GW/cm² and 6.4 GW/cm²) of LSP were chosen and tested using manufactured fretting fatigue apparatus. The experimental results show that the LSP surface treatment significantly improves the fretting fatigue lives of the fretting specimens, and the fretting fatigue life increases most when the laser power density is 4.8 GW/cm². It is also found that with the increase of the laser power density, the fatigue crack initiation location tends to move from the surface to the interior of the specimen.

Molecular and structural imaging in surgically induced murine osteoarthritis

Preclinical imaging in osteoarthritis is a rapidly growing area with three principal objectives: to provide rapid, sensitive tools to monitor the course of experimental OA longitudinally; to describe the temporal relationship between tissue-specific pathologies over the course of disease; and to use molecular probes to measure disease activity in vivo. Research in this area can be broadly divided into those techniques that monitor structural changes in tissues (microCT, microMRI, ultrasound) and those that detect molecular disease activity (positron emission tomography (PET), optical and optoacoustic imaging). The former techniques have largely evolved from experience in human joint imaging and have been refined for small animal use. Some of the latter tools, such as optical imaging, have been developed in preclinical models and may have translational benefit in the future for patient stratification and for monitoring disease progression and response to treatment. In this narrative review we describe these methodologies and discuss the benefits to animal research, understanding OA pathogenesis, and in the development of human biomarkers.

QTL for horticulturally important traits associated with pleiotropic andromonoecy and carpel number loci, and a paracentric inversion in cucumber

The legendary cucumber inbred line WI2757 possesses a rare combination of resistances against nine pathogens, which is an important germplasm for cucumber breeding. However, WI2757 flowers late and does not perform well under field conditions. The genetic basis for horticulturally important traits other than disease resistances in WI2757 is largely unknown. In this study, we conducted QTL mapping using F₂ and recombinant inbred line (RIL) populations from the WI2757 × True Lemon cross that were segregating for multiple traits. Phenotypic data were collected in replicated field trials across multiple years for seven traits including fruit carpel number (CN) and sex expression. A high-density SNP-based genetic map was developed with genotyping by sequencing of the RIL population, which revealed a region on chromosome 1 with strong recombination suppression. The reduced recombination in this region was due to a ~ 10-Mbp paracentric inversion in WI2757 that was confirmed with additional segregation and cytological (FISH) analyses. Thirty-six QTL were detected for flowering time, fruit length (FL), fruit diameter (FD), fruit shape (LD), fruit number (FN), CN, and powdery mildew resistance. Five moderate- or major-effect QTL for FL, FD, LD, and FN inside the inversion are likely the pleiotropic effects of the andromonoecy (m), or the cn locus. The major-effect flowering time QTL ft1.1 was also mapped inside the inversion, which seems to be different from the previously assigned delayed flowering in WI2757. Implications of these findings on the use of WI2757 in cucumber breeding are discussed.

A biotechnology-based male-sterility system for hybrid seed production in tomato

Incorporating male sterility into hybrid seed production reduces its cost and ensures high varietal purity. Despite these advantages, male-sterile lines have not been widely used to produce tomato (Solanum lycopersicum) hybrid seeds. We describe the development of a biotechnology-based breeding platform that utilized genic male sterility to produce hybrid seeds. In this platform, we generated a novel male-sterile tomato line by clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated protein 9 (Cas9)-mediated mutagenesis of a stamen-specific gene SlSTR1 and devised a transgenic maintainer by transforming male-sterile plants with a fertility-restoration gene linked to a seedling-colour gene. Offspring of crosses between a hemizygous maintainer and the homozygous male-sterile plant segregated into 50% non-transgenic male-sterile plants and 50% male-fertile maintainer plants, which could be easily distinguished by seedling colour. This system has great practical potential for hybrid seed breeding and production as it overcomes the problems intrinsic to other male-sterility systems and can be easily adapted for a range of tomato cultivars and diverse vegetable crops.

siRNA and chemotherapeutic molecules entrapped into a redox-responsive platform for targeted synergistic combination therapy of glioma

Vascular endothelial growth factor (VEGF) has been implicated as the key regulator of tumor neovascularization. RNAi interference plays a critical role on down-regulation of VEGF, while single VEGF inhibition could not completely suppress angiogenesis and tumor growth; the effect of siRNA is temporary. To improve glioma therapy efficacy, an angiopep-2 (Ap) modified redox-responsive glycolipid-like copolymer co-delivering siVEGF and paclitaxel (PTX), termed as Ap-CSssSA/P/R complexes, was developed in this study. Ap modification significantly enhanced the distribution of Ap-CSssSA in glioma cells both in vitro and in vivo. Ap-CSssSA/P/R complexes could simultaneously deliver siVEGF and PTX into tumor cells, exhibiting great superiority in glioma growth suppression via receptor-mediated targeting delivery and cell apoptosis, accompanied with an obvious inhibition of neovascularization induced by VEGF gene silencing. The present study indicated that the combination delivery of siVEGF and PTX via Ap-modified copolymeric micelles presented a promising and safe platform for glioma targeted therapeutics.

[Analysis of broadband sinusoidal harmonic acceleration test results for normal young people]

Objective: We tested more frequency (0.01-3.0 Hz) of the sinusoidal harmonic acceleration test(SHAT) by the NKI rotation chair, aimed to analyze the results of the normal youth. Methods: Fifty normal young people were tested with sinusoidal harmonic acceleration by NKI rotation chair. Including 24 men and 26 women, aged from 20 to 40 years old, with median age of 27 years, with no vestibular dysfunction participated in the present study. All the volunteers accepted the sinusoidal harmonic acceleration test by the NKI rotation chair, the frequency included 0.01 Hz, 0.02 Hz, 0.03 Hz, 0.05 Hz, 0.1 Hz, 0.2 Hz, 0.3 Hz, 0.6 Hz, 1.0 Hz, 1.5 Hz, 2.0 Hz, 3.0 Hz. Taken the gain, phase, and asymmetry as the parameters, the trait of each frequency was analysed. Results: From 0.01 Hz to 1.5 Hz, the gain increased close to 1 gradually, and with fluctuates slightly at the 2.0 Hz and 3.0 Hz frequencies. The phase decreased as frequencies increased close to 0 at 0.3 Hz. The frequency above 0.6 Hz presented negative. Asymmetric values were distributed on both positive and negative sides at each frequency and were different from each other, both values were less than 20%. Conclusion: Broadband SHAT can accurately assess the horizontal semicircular canal function at different frequencies in a wider frequency range, and objectively, reflect the physiological function of the horizontal semicircular canal, and expand the clinical value of traditional SHAT.

Recent progress on the molecular breeding of Cucumis sativus L. in China

Molecular breeding of Cucumis sativus L. is based on traditional breeding techniques and modern biological breeding in China. There are opportunities for further breeding improvement by molecular design breeding and the automation of phenotyping technology using untapped sources of genetic diversity. Cucumber (Cucumis sativus L.) is an important vegetable cultivated worldwide. It bears fruits of light fragrance, and crisp texture with high nutrition. China is the largest producer and consumer of cucumber, accounting for 70% of the world's total production. With increasing consumption demand, the production of Cucurbitaceae crops has been increasing yearly. Thus, new cultivars that can produce high-quality cucumber with high yield and easy cultivation are in need. Conventional genetic breeding has played an essential role in cucumber cultivar innovation over the past decades. However, its progress is slow due to the long breeding period, and difficulty in selecting stable genetic characters or genotypes, prompting researchers to apply molecular biotechnologies in cucumber breeding. Here, we first summarize the achievements of conventional cucumber breeding such as crossing and mutagenesis, and then focus on the current status of molecular breeding of cucumber in China, including the progress and achievements on cucumber genomics, molecular mechanism underlying important agronomic traits, and also on the creation of high-quality multi-resistant germplasm resources, new variety breeding and ecological breeding. Future development trends and prospects of cucumber molecular breeding in China are also discussed.

Genome-based breeding approaches in major vegetable crops

Vegetable crops are major nutrient sources for humanity and have been well-cultivated since thousands of years of domestication. With the rapid development of next-generation sequencing and high-throughput genotyping technologies, the reference genome of more than 20 vegetables have been well-assembled and published. Resequencing approaches on large-scale germplasm resources have clarified the domestication and improvement of vegetable crops by human selection; its application on genetic mapping and quantitative trait locus analysis has led to the discovery of key genes and molecular markers linked to important traits in vegetables. Moreover, genome-based breeding has been utilized in many vegetable crops, including Solanaceae, Cucurbitaceae, Cruciferae, and other families, thereby promoting molecular breeding at a single-nucleotide level. Thus, genome-wide SNP markers have been widely used, and high-throughput genotyping techniques have become one of the most essential methods in vegetable breeding. With the popularization of gene editing technology research on vegetable crops, breeding efficiency can be rapidly increased, especially by combining the genomic and variomic information of vegetable crops. This review outlines the present genome-based breeding approaches used for major vegetable crops to provide insights into next-generation molecular breeding for the increasing global population.

A new SNP genotyping technology Target SNP-seq and its application in genetic analysis of cucumber varieties

To facilitate the utility of SNP-based genotyping, we developed a new method called target SNP-seq which combines the advantages of multiplex PCR amplification and high throughput sequencing. Compared with KASP, Microarrays, GBS and other SNP genotyping methods, target SNP-seq is flexible both in SNPs and samples, yields high accuracy, especially when genotyping genome wide perfect SNPs with high polymorphism and conserved flanking sequences, and is cost-effective, requiring 3 days and $7 for per DNA sample to genotype hundreds of SNP loci. The present study established a DNA fingerprint of 261 cucumber varieties by target SNP-seq with 163 perfect SNPs from 4,612,350 SNPs based on 182 cucumber resequencing datasets. Four distinct subpopulations were found in 261 Chinese cucumber varieties: the north China type, the south China type, the Europe type, and the Xishuangbanna type. The north China type and Xishuangbanna type harbored lower genetic diversity, indicating greater risk of genetic erosion in these two subpopulations. Furthermore, a core set of 24 SNPs was able to distinguish 99% of the 261 cucumber varieties. 29 core cucumber backbone varieties in China were identified. Therefore, target SNP-seq provides a new way to screen out core SNP loci from the whole genome for DNA fingerprinting of crop varieties. The high efficiency and low cost of target SNP-seq is more competitive than the current SNP genotyping methods, and it has excellent application prospects in genetic research, as well as in promoting plant breeding processes in the near future.

ULK1 polymorphisms confer susceptibility to pulmonary tuberculosis in a Chinese population

OBJECTIVE

The autophagy pathway is a critical process in Mycobacterium tuberculosis infection, and can be regulated by uncoordinated 51-like kinase 1 (ULK1). We investigated the associations between single-nucleotide polymorphisms (SNPs) in ULK1 and risk of tuberculosis (TB) in a Chinese Han population.

DESIGN

We recruited 380 pulmonary tuberculosis (PTB) cases, 242 extra-pulmonary tuberculosis (EPTB) cases and 606 healthy controls from a Chinese Han population and sequenced ULK1. Five SNPs in ULK1 were selected to investigate the correlations between ULK1 polymorphisms and TB susceptibility.

RESULTS

The rs7138581 C allele was associated with a reduced risk of PTB (P = 0.001), whereas the rs9481 A allele was associated with an increased risk (P = 0.025). The rs7138581 CG genotype was significantly associated with a low risk of PTB, with a higher PTB disease severity in clinical parameters. Estimation of haplotype frequencies in ULK1 revealed a protective haplotype CCGAA (P = 0.007) and a potential risk haplotype TGAAA (P = 0.010) for PTB.

CONCLUSION

These results demonstrated that ULK1 polymorphisms have significant associations with susceptibility to PTB.

Molecularly tagged genes and quantitative trait loci in cucumber with recommendations for QTL nomenclature

Cucumber, Cucumis sativus L. (2n = 2x = 14), is an important vegetable crop worldwide. It was the first specialty crop with a publicly available draft genome. Its relatively small, diploid genome, short life cycle, and self-compatible mating system offers advantages for genetic studies. In recent years, significant progress has been made in molecular mapping, and identification of genes and QTL responsible for key phenotypic traits, but a systematic review of the work is lacking. Here, we conducted an extensive literature review on mutants, genes and QTL that have been molecularly mapped or characterized in cucumber. We documented 81 simply inherited trait genes or major-effect QTL that have been cloned or fine mapped. For each gene, detailed information was compiled including chromosome locations, allelic variants and associated polymorphisms, predicted functions, and diagnostic markers that could be used for marker-assisted selection in cucumber breeding. We also documented 322 QTL for 42 quantitative traits, including 109 for disease resistances against seven pathogens. By alignment of these QTL on the latest version of cucumber draft genomes, consensus QTL across multiple studies were inferred, which provided insights into heritable correlations among different traits. Through collaborative efforts among public and private cucumber researchers, we identified 130 quantitative traits and developed a set of recommendations for QTL nomenclature in cucumber. This is the first attempt to systematically summarize, analyze and inventory cucumber mutants, cloned or mapped genes and QTL, which should be a useful resource for the cucurbit research community.

Dietary mannan oligosaccharide ameliorates cyclic heat stress-induced damages on intestinal oxidative status and barrier integrity of broilers

This study investigated protective effects of mannan oligosaccharide (MOS) inclusion on growth performance, intestinal oxidative status, and barrier integrity of cyclic heat-stressed broilers. A total of 240 one-day-old chicks were allocated into 3 treatments of 10 replicates each. Control broilers reared at a thermoneutral temperature were fed a basal diet, whereas broilers in heat stress and MOS groups raised at a cyclic high temperature (32 to 33°C for 8 h/d) were given the basal diet supplemented with 0 or 250 mg/kg MOS, respectively. Compared with control group, heat stress decreased (P < 0.05) average daily gain and feed conversion ratio during grower, finisher, and entire periods, average daily feed intake during finisher and entire periods, and ileal superoxide dismutase activity at 42 D, whereas increased (P < 0.05) rectal temperature at 21 and 42 D and jejunal malondialdehyde content at 42 D. Dietary MOS increased (P < 0.05) average daily gain, average daily feed intake, and feed conversion ratio during finisher and entire periods, but decreased (P < 0.05) jejunal malondialdehyde concentration of heat-stressed broilers at 42 D. Heat stress decreased (P < 0.05) jejunal villus height (VH) and claudin-3 gene expression at 21 D, and VH and VH: crypt depth (CD) ratio in jejunum and ileum as well as mRNA abundances of jejunal mucin 2 and occludin, and ileal mucin 2, zonula occludens-1, and occludin, and claudin-3 at 42 D, whereas increased (P < 0.05) serum D-lactate acid content at 21 and 42 D, and serum diamine oxidase activity and jejunal CD at 42 D. The MOS supplementation increased (P < 0.05) jejunal VH at 21 D, VH and VH: CD of jejunum and ileum at 42 D, mRNA abundances of jejunal occludin and ileal mucin 2, zonula occludens-1, and occludin at 42 D, whereas reduced (P < 0.05) ileal CD at 42 D. These results suggested that MOS improved growth performance, and oxidative status and barrier integrity in the intestine of broilers under cyclic heat stress.

Target sequencing reveals genetic diversity, population structure, core-SNP markers, and fruit shape-associated loci in pepper varieties

BACKGROUND

The widely cultivated pepper (Capsicum spp.) is one of the most diverse vegetables; however, little research has focused on characterizing the genetic diversity and relatedness of commercial varieties grown in China. In this study, a panel of 92 perfect single-nucleotide polymorphisms (SNPs) was identified using re-sequencing data from 35 different C. annuum lines. Based on this panel, a Target SNP-seq genotyping method was designed, which combined multiplex amplification of perfect SNPs with Illumina sequencing, to detect polymorphisms across 271 commercial pepper varieties.

RESULTS

The perfect SNPs panel had a high discriminating capacity due to the average value of polymorphism information content, observed heterozygosity, expected heterozygosity, and minor allele frequency, which were 0.31, 0.28, 0.4, and 0.31, respectively. Notably, the studied pepper varieties were morphologically categorized based on fruit shape as blocky-, long horn-, short horn-, and linear-fruited. The long horn-fruited population exhibited the most genetic diversity followed by the short horn-, linear-, and blocky-fruited populations. A set of 35 core SNPs were then used as kompetitive allele-specific PCR (KASPar) markers, another robust genotyping technique for variety identification. Analysis of genetic relatedness using principal component analysis and phylogenetic tree construction indicated that the four fruit shape populations clustered separately with limited overlaps. Based on STRUCTURE clustering, it was possible to divide the varieties into five subpopulations, which correlated with fruit shape. Further, the subpopulations were statistically different according to a randomization test and F_st statistics. Nine loci, located on chromosomes 1, 2, 3, 4, 6, and 12, were identified to be significantly associated with the fruit shape index (p < 0.0001).

CONCLUSIONS

Target SNP-seq developed in this study appears as an efficient power tool to detect the genetic diversity, population relatedness and molecular breeding in pepper. Moreover, this study demonstrates that the genetic structure of Chinese pepper varieties is significantly influenced by breeding programs focused on fruit shape.

Silicosis in rhinestone-manufacturing workers in South China

BACKGROUND

Silicosis is caused by long-term exposure to silica dust. Crystal rhinestone workers can be exposed to high levels of silica dust and are at risk of silicosis.

AIMS

To explore silicosis cases, silica dust exposure and control measures in a rhinestone factory in South China.

METHODS

We extracted and analysed data on new silicosis cases reported to China's occupational disease and occupational health information monitoring system between 2006 and 2012 from a rhinestone factory in South China. We measured the quartz content of bulk dust, static total and respirable dust samples.

RESULTS

Ninety-eight silicosis cases were reported between 2006 and 2012. The mean duration of silica dust exposure was 9.2 years (range 3-16). Drilling and polishing workers accounted for 96 (98%) of cases. We collected 1479 static samples including 690 total dust and 789 respirable dust samples. Mean dust levels for drilling were 1.01 mg/m3 (range 0.20-3.80) for total dust and 0.51 mg/m3 (range 0.04-1.70) for respirable dust. Mean dust levels for polishing were 0.59 mg/m3 (range 0.20-2.10) for total dust and 0.28 mg/m3 (range 0.08-0.71) for respirable dust. Over a third [289/789 (37%)] of total dust samples and 129/690 (19%) respirable dust samples exceeded the national permissible exposure limit.

CONCLUSION

Exposure to silica dust, ineffective dust control measures and inefficient health surveillance may have contributed to the incidence of silicosis in the factory we studied. Identification of silica dust exposure and effective dust control measures would reduce the risk of silicosis in rhinestone workers.

Identification of a Major QTL (qRRs-10.1) That Confers Resistance to Ralstonia solanacearum in Pepper (Capsicum annuum) Using SLAF-BSA and QTL Mapping

The soilborne pathogen Ralstonia solanacearum is the causal agent of bacterial wilt (BW), a major disease of pepper (Capsicum annuum). The genetic basis of resistance to this disease in pepper is not well known. This study aimed to identify BW resistance markers in pepper. Analysis of the dynamics of bioluminescent R. solanacearum colonization in reciprocal grafts of a resistant (BVRC 1) line and a susceptible (BVRC 25) line revealed that the resistant rootstock effectively suppressed the spreading of bacteria into the scion. The two clear-cut phenotypic distributions of the disease severity index in 440 F2 plants derived from BVRC 25 × BVRC 1 indicated that a major genetic factor as well as a few minor factors that control BW resistance. By specific-locus amplified fragment sequencing combined with bulked segregant analysis, two adjacent resistance-associated regions on chromosome 10 were identified. Quantitative trait (QTL) mapping revealed that these two regions belong to a single QTL, qRRs-10.1. The marker ID10-194305124, which reached a maximum log-likelihood value at 9.79 and accounted for 19.01% of the phenotypic variation, was located the closest to the QTL peak. A cluster of five predicted R genes and three defense-related genes, which are located in close proximity to the significant markers ID10-194305124 or ID10-196208712, are important candidate genes that may confer BW resistance in pepper.