[Clinical analysis of two cases of imported children Zika virus infection in China].

OBJECTIVE: To analyze the clinical characteristics, outcome and diagnosis of two cases of imported children Zika virus infection in China. METHOD: A retrospective analysis was performed on clinical characteristics, treatment and outcome of two cases of imported children with Zika virus infection in February 2016 in Enping People's Hospital of Guangdong. RESULT: Two cases of children with imported Zika virus infection resided in an affected area of Venezuela, 8-year-old girl and her 6 year-old brother. The main findings on physical examination included the following manifestations: fever, rash, and conjunctivitis. The rash was first limited to the abdomen, but extended to the torso, neck and face, and faded after 3-4 d. The total number of white blood cells was not high and liver function was normal. The diagnosis of two cases of Zika virus infection was confirmed by the expert group of Guangdong Provincial Center for Disease Control and Prevention, according to the epidemiological history, clinical manifestations and Zika virus nucleic acid detection results.Treatment of Zika virus infection involves supportive care. Two Zika virus infection children had a relatively benign outcome. CONCLUSION: At present, Zika virus infection in children is an imported disease in China. No specific therapy is available for this disease. Information on long-term outcomes among infants and children with Zika virus disease is limited, routine pediatric care is advised for these infants and children.

Cloning and expression analysis of heat-shock transcription factor gene CaHsfA2 from pepper (Capsicum annuum L.).

The heat-shock transcription factor (Hsf) gene CaHsfA2 (GenBank accession No. JX402923) was cloned from the Capsicum annuum thermotolerant line R9 by combining the techniques electron cloning and rapid amplification of cDNA ends. The gene, which is 1436 bp in length, had an open reading frame of 1089 bp that encoded 362 amino acids. There was an 831-bp intron between positions 321 and 322 of the cDNA. The deduced amino acid sequence of CaHsfA2 contained the conserved domains of Hsf, including DNA binding domain, adjacent domain with heptad hydrophobic repeats (A/B), activator motifs, nuclear localization signal, and nuclear export signal, and it had the highest E value of hypothesized annotation of HsfA2. CaHsfA2 had the nearest phylogenetic relationship with HsfA2 from Lycopersicon peruvianum and Mimulus guttatus, which was consistent with its botanical classification. After heat-shock treatment at 40°C for 2 h, the expression of CaHsfA2 was observed in different tissues of thermotolerant cultivar R9 and thermosensitive line B6; however, the expression levels of the CaHsfA2 gene were significantly different as follows: expression in B6 leaf > stem > flower > root, and expression in R9 flower > leaf > stem ≈ root.

Genetic determinants of the defense response of resistant and susceptible pepper (Capsicum annuum) cultivars infected with Phytophthora capsici (Oomycetes; Pythiaceae).

Based on culture isolation and morphological observation blight-infected pepper plants in Shaanxi Province, China, we identified the pathogen causing pepper phytophthora blight as Phytophthora capsici. Varieties that differed in resistance (CM334, PBC602, and B27) were inoculated with this pathogen. The root activity of resistant CM334 variety was the highest while that of susceptible B27 variety was the lowest. Also, significant differences in the activity of POD, PAL, and ß-1,3-glucanase were found; there was a positive correlation between disease resistance and activity of these three enzymes. We inhibited mycelial growth and sporangia formation of P. capsici using crude ß-1,3-glucanase and PAL enzymes isolated from the resistant variety CM334 after it had been inoculated with P. capsici. These two enzymes had a synergistic effect on inhibition of P. capsici mycelial growth and sporangia formation. Expression of the defensive genes CaPO1, CaBGLU, CaBPR1, and CaRGA in the three varieties was higher in the leaves than in the roots. All three genes were upregulated in infected leaves and roots of the pepper plants, always expressing at higher levels in the resistant cultivar than in the susceptible cultivar, suggesting that the differences in resistance among the pepper genotypes involve differences in the timing and magnitude of the defense response.

Exogenous abscisic acid increases antioxidant enzymes and related gene expression in pepper (Capsicum annuum) leaves subjected to chilling stress.

To elucidate how physiological and biochemical mechanisms of chilling stress are regulated by abscisic acid (ABA) pretreatment, pepper variety (cv. 'P70') seedlings were pretreated with 0.57 mM ABA for 72 h and then subjected to chilling stress at 10°/6°C (day/night). Chilling stress caused severe necrotic lesions on the leaves and increased malondialdehyde and H(2)O(2) levels. Activities of monodehydroascorbate reductase (DHAR), dehydroascorbate reductase, glutathione reductase, guaiacol peroxidase, ascorbate peroxidase, ascorbate, and glutathione increased due to chilling stress during the 72 h, while superoxide dismutase and catalase activities decreased during 24 h, suggesting that chilling stress activates the AsA-GSH cycle under catalase deactivation in pepper leaves. ABA pretreatment induced significant increases in the above-mentioned enzyme activities and progressive decreases in ascorbate and glutathione levels. On the other hand, ABA-pretreated seedlings under chilling stress increased superoxide dismutase and guaiacol peroxidase activities and lowered concentrations of other antioxidants compared with untreated chilling-stressed plants. These seedlings showed concomitant decreases in foliage damage symptoms, and levels of malondialdehyde and H(2)O(2). Induction of Mn-SOD and POD was observed in chilling-stressed plants treated with ABA. The expression of DHAR1 and DHAR2 was altered by chilling stress, but it was higher in the presence than in the absence of ABA at 24 h. Overall, the results indicate that exogenous application of ABA increases tolerance of plants to chilling-induced oxidative damage, mainly by enhancing superoxide dismutase and guaiacol peroxidase activities and related gene expression.

Construction of the intermediate vector pVBG2307 by incorporating vital elements of expression vectors pBI121 and pBI221.

Molecular chaperones of plasmid pBI121 carrying CaMV35S promoter and a nucleotide sequence of plasmid pBI221 were inserted into plasmid pCAMBIA2300 to construct an intermediate vector: pVBG2307. This novel vector pVBG2307 contains a greatly expanded multiple cloning site with an adjacent imported CaMV35S promoter sequence. This vector allows controlled transformation of DNA in both Escherichia coli and Agrobacterium tumefaciens. Cloned PG, orf456, ipt genes and E8, a fruiting promoter, were amplified by PCR of cDNA libraries of Capsicum annum and Lycopersicon esculentum and were then transferred into vector pVBG2307. The viability of this vector was demonstrated, as it regulated PG, orf456, ipt and E8 genes in E. coli and could be transferred into Agrobacterium strain EHA105-4.

Activity and expression of polygalacturonase vary at different fruit ripening stages of sweet pepper cultivars.

Activity and expression of polygalacturonase (PG), a hydrolytic enzyme involved in ultrastructural changes in the pericarp of sweet pepper (Capsicum annaum), were investigated at different ripening stages of the pepper cultivars Mandi and Talanduo. Molecular cloning of CaPG was carried out by constructing a cDNA library from three stages of fruit ripening. Morphological determination, PG assay, RT-PCR, and ultrastructural studies were used to quantify changes in CaPG gene expression in the pericarp from green, color change and fully ripened stages. We found that CaPG gene expression, PG activity and striking changes in the structure of the cell wall occurred with the transition of ripening stages. CaPG gene expression was high (obvious PCR products) in mature and ripened stages of both cultivars; however, the CaPG gene was not expressed in preclimacteric fruits or vegetative tissues. We conclude that developmental regulation of CaPG gene expression is instrumental for sweet pepper fruit ripening; its expression during development leads to dissolution of middle lamella and eventually disruption of the fully ripened cell wall.