RESUMEN
Cucumbers (Cucumis sativus L.) originated from the South Asian subcontinent, and most of them are fragile to cold stress. In this study, we evaluated the cold tolerance of 115 cucumber accessions and screened out 10 accessions showing high resistance to cold stress. We measured and compared plant hormone contents between cold-tolerant cucumber CT90R and cold-sensitive cucumber CT57S in cold treatment. Most of the detected plant hormones showed significantly higher content in CT90R. To elucidate the role of plant hormones, we compared the leaf- and root-transcriptomes of CT90R with those of CT57S in cold stress treatment. In leaves, there were 1209 differentially expressed genes (DEGs) between CT90R and CT57S, while there were 703 in roots. These DEGs were not evenly distributed across the chromosomes and there were significant enrichments at particular positions, including qLTT6.2, a known QTL controlling cucumber cold tolerance. The GO and KEGG enrichment analysis showed that there was a significant difference in the pathway of plant hormone transductions between CT90R and CT57S in leaves. In short, genes involved in plant hormone transductions showed lower transcription levels in CT90R. In roots, the most significantly different pathway was phenylpropanoid biosynthesis. CT90R seemed to actively accumulate more monolignols by upregulating cinnamyl-alcohol dehydrogenase (CAD) genes. These results above suggest a new perspective on the regulation mechanism of cold tolerance in cucumbers.
RESUMEN
The highly enantioselective copper-catalyzed propargylic amination of propargylic esters with amine hydrochloride salts has been realized for the first time using copper salts with chiral N,N,P-ligands. This method features a broad substrate scope and wide functional group tolerance, generating propargylic amines in good to excellent yields with high enantioselectivities (up to 99% ee). The utility of the approach was demonstrated by late-stage functionalization of marketed pharmaceuticals.
RESUMEN
A highly enantioselective copper-catalyzed propargylic amination starting from benzylic allylic amines has been developed with a new chiral N,N,P ligand. A series of N-tethered 1,6-enynes were synthesized in good to excellent yields with excellent enantioselectivities. Utilization of transition metal-catalyzed cycloisomerization of 1,6-enynes provides several enantioselectively enriched chiral five-membered N-heterocycles efficiently.
RESUMEN
OBJECTIVE: To investigate human papilloma virus (HPV) infection in the male genital tract and its risk factors in some rural areas of Jiangsu Province. METHODS: This study included 398 men from six rural areas in Jiangsu Province, whose female partners, based on the results of cervical cytological examination, were divided into a normal (n = 104), a cervical intraepithelial neoplasia grade â (CIN-â , n = 100), a CIN-â ¡ (n = 95), and a CIN-â ¢ group (n = 99). We examined the male subjects for genital warts and other lesions, collected urethral swab samples for HPV detection, and obtained their sociodemographic data by questionnaire investigation. RESULTS: No megascopic lesions were observed in the genitals of the 398 participants. The total prevalence rate of HPV infection was 11.31% and that of high-risk HPV was 8.54%. Logistic regression analysis showed that daily cleaning of the genitals significantly decreased the risk of HPV infection (OR = 3.030, P = 0.003). CONCLUSIONS: There is a relatively high prevalence rate of recessive infection of genital HPV among the seemingly healthy males in the rural area of Jiangsu Province. Daily cleaning of the genitals may be a protective measure against HPV infection.