Polyamines inhibit abscisic acid-induced stomatal closure by scavenging hydrogen peroxide.

Stomatal closure is regulated by plant hormones and some small molecules to reduce water loss under stress conditions. Both abscisic acid (ABA) and polyamines alone induce stomatal closure; however, whether the physiological functions of ABA and polyamines are synergistic or antagonistic with respect to inducing stomatal closure is still unknown. Here, stomatal movement in response to ABA and/or polyamines was tested in Vicia faba and Arabidopsis thaliana, and the change in the signaling components under stomatal closure was analyzed. We found that both polyamines and ABA could induce stomatal closure through similar signaling components, including the synthesis of hydrogen peroxide (H2 O2 ) and nitric oxide (NO) and the accumulation of Ca2+ . However, polyamines partially inhibited ABA-induced stomatal closure both in epidermal peels and in planta by activating antioxidant enzymes, including superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT), to eliminate the ABA-induced increase in H2 O2 . These results strongly indicate that polyamines inhibit abscisic acid-induced stomatal closure, suggesting that polyamines could be used as potential plant growth regulators to increase photosynthesis under mild drought stress.

Clinical features of Chinese children with COVID-19 and other viral respiratory infections.

OBJECTIVE: Few studies have explored the clinical features in children infected with SARS-CoV-2 and other common respiratory viruses, including respiratory syncytial virus (RSV), Influenza virus (IV), and adenovirus (ADV). Herein, we reported the clinical characteristics and cytokine profiling in children with COVID-19 or other acute respiratory tract infections (ARTI). METHODS: We enrolled 20 hospitalized children confirmed as COVID-19 positive, 58 patients with ARTI, and 20 age and sex-matched healthy children. The clinical information and blood test results were collected. A total of 27 cytokines and chemokines were measured and analyzed. RESULTS: The median age in the COVID-19 positive group was 14.5 years, which was higher than that of the ARTI groups. Around one-third of patients in the COVID-19 group experienced moderate fever, with a peak temperature of 38.27°C. None of the patients displayed wheezing or dyspnea. In addition, patients in the COVID-19 group had lower white blood cells, platelet counts as well as a neutrophil-lymphocyte ratio. Lower serum concentrations of 14 out of 27 cytokines were observed in the COVID-19 group than in healthy individuals. Seven cytokines (IL-1Ra, IL-1ß, IL-9, IL-10, TNF-α, MIP-1α, and VEGF) changed serum concentration in COVID-19 compared with other ARTI groups. CONCLUSION: Patients with COVID-19 were older and showed milder symptoms and a favorable prognosis than ARTI caused by RSV, IV, and ADV. There was a low grade or constrained innate immune reaction in children with mild COVID-19.

Complete genome sequence of a dengue virus serotype 4 strain isolated in Guangdong, China.

Here we report the first complete genome sequence of a dengue virus serotype 4 genotype II strain, GZ30, isolated in Guangzhou, Guangdong Province, China, in 2010. The sequence information provided herein will help us to understand the molecular epidemiology of dengue virus and predict the risk of severe diseases in mainland China.

[Molecular mechanism of acupoint catgut-embedding for experimental colitis in rats].

OBJECTIVE: To explore the effect and its mechanism of acupoint catgut-embedding for experimental colitis in rats. METHODS: Eighteen SD rats were randomly divided into a normal control (NC) group, a model (MO) group and a acupoint catgut-embedding (AC) group, 6 rats in each group. Animals in MO group and AC group were treated by trinitro-benzene-sulfonic acid (TNBS) to establish model with colitis. No other treatment was given to the rats in MO group, but acupoint catgut-embedding was implanted at "Shangjuxu" (ST 37), "Tianshu" (ST 25) and "Dachangshu" (BL 25) in the rats in AC group. The symptoms of diarrhea and bloody stool, and histopathology changes in colon were observed 15 days after the treatment. Expression of IL-17, beta2AR, NFkappaBp65 were observed by immunohistochemistry. Expressions of NF-kappaBp65 and beta2AR in splenic lymphocyte were detected by the Western blot method. RESULTS: Diarrhea and mucus bloody purulent stool were soon controlled, and colon mucosa injures were obviously improved in AC group. The NF-kappaBp65 value in splenic lymphocytes of 249.70 +/- 13.66 in MO) group was higher than 86.22 +/- 8.09 in NC group (P < 0.01), and 219.02 +/- 7.42 in AC group was less than that in MO group (P < 0.01). The expression of beta2AR in splenic lymphocytes of 594.97 +/- 173.22 in MO group was less than 957.45 +/- 171.56 in NC group (P < 0.01), and 1335.93 +/- 244.34 in AC group was higher than that in MO group (P < 0.01). The expression of IL-17 in colon mucosa in MO group was increased, while the expression of IL-17 in colon mucosa in AC group was decreased. CONCLUSION: Acupoint catgut-embedding at Shangjuxu (ST 37), Tianshu (ST 25) and Dachangshu (BL 25) has obviously effect in treating experimental colitis and the mechanism may be related to regulate the expression of IL-17, beta2AR and NF-kappaBp65.

[Selection of basic acupoints for composing "gastric-disorder-formula" for electroacupuncture prevention of acute gastric mucosal lesion in rats].

OBJECTIVE: To select the best combination of the commonly-used acupoints [Zhongwan (CV 12), Neiguan (PC 6), and Zusanli (ST 36)] for treatment of gastric disorders. METHODS: Forty-eight Wistar rats were randomly divided into 8 groups: model, ST36, CV12, PC6, ST36 + PC6, ST36 + CV12, CV12 + PC6 and ST36 + CV12 + PC6 by factorial design method. Acute gastric mucosal lesion model was established by intragastric perfusion of anhydrous alcohol. EA(1- 3 mA, 30 Hz) was applied to the above-mentioned acupoints for 20 min respectively. And after EA, gastric mucosal lesion index (LI), pathological lesion integral score (PLIS) were calculated and mucosal ultramicrostructural changes observed by optical microscope and transmission electron microscope respectively. RESULTS: Compared with model group, the gastric mucosal LI and PLIS of ST36, CV12, PC6, ST36 + CV12, ST36 + PC6, CV12 + PC6, ST36 + CV12 + PC6 groups all decreased significantly (P < 0.05). Comparison among 7 EA groups showed that both LI and PLIS of ST36 + CV12 + PC6 group were significantly lower than those of ST36, V12, PC6, ST36 + CV12, ST36 + PC6 and CV12 + PC6 groups (P < 0.05). No significant differences were found between every two groups of ST36, CV12, PC6, ST36+ CV12, ST36 + PC6 and CV12 + PC6 groups (P > 0.05) in both LI and PLIS. Ultrastructural results showed that the injury of gastric mucosal parietal cells and delomorphous cells including mitochondrial swelling, crista arrange disorder and breaking, enlargement of the rough endoplasmic reticulum, ribosome exfoliation, etc. in model group was serious, but lightened significantly in EA groups particularly in ST36 + CV12 + PC6 group. CONCLUSION: ST36, PC6 and CV12 combination can effectively reduce anhydrous alcohol-induced gastric mucosal lesion in rats, and may be used as a basic formula

[Effects of electroacupuncture at points "Weibingfang" on EGF and EGFR mRNA expressions in rats with lesion of gastric mucosa].

OBJECTIVE: To probe the mechanism of electroacupuncture at points "Weibingfang" in treatment of acute gastric mucosal lesion. METHODS: Forty Wistar rats of sanitary degree were randomly divided into 4 groups, normal group, model group, sham-model group and Weibingfang group, 10 rats in each group. The acute gastric mucosal lesion model was made by intragastric perfusion of anhydrous alcohol. The Weibingfang group were treated by electroacupuncture at "Neiguan" (PC 6), "Zhongwan" (CV 12) and "Zusanli" (ST 36) with sparse-dense wave, frequency of 10-30 Hz, current intensity of 2 mA, for 20 min. One hour after the treatment, the blood from the abdominal aorta and the gastric mucosa tissue were taken, and serum epidermal growth factor (EGF) level and epidermic growth factor receptor mRNA (EGFR mRNA) expression in the gastric mucosa were detected with enzyme linked immunosorbent assay (ELISA) and reverse transcriptase-polymerase chain reaction (RT-PCR) respectively. RESULTS: There were significant differences in blood EGF level (41.62 +/- 12.58) ng/L and EGFR mRNA expression (0.78 +/- 0.03) in the model group were significantly different from [(60.37 +/- 12.01) ng/L and 0.55 +/- 0.04] in the normal group and [(61.21 +/- 13.46) ng/L and 0.53 +/- 0.05] in the sham-model group (P < 0.05); after electroacupuncture, blood EGF level (70.59 +/- 10.14) ng/L increased and the EGFR mRNA expression (1.18 +/- 0.02) in the gastric mucosa was up-regulated with a significant differences as compared with those in the model group (P < 0.05). CONCLUSION: Point "Weibingfang" can promote proliferation, differentiation and migration of the gastric mucosal epidermic cells to repair the gastric mucosal lesion.

[Survey on the relationship between pathological reactions of acupoints and Zangfu organs/meridians].

In this article, the authors make an analysis on the regularity of correlation between pathological reactions of acupoints and Zangfu organs/meridians, current clinical application and mechanism research, and summarize the relative specificity of the correlation between abnormal reactions of acupoints and states of Zangfu organs/meridians. In addition, the authors also point out some shortcomings in current researches on the above-mentioned aspects, for examples, only observation on the phenomenon without definite conclusion on the regularity of acupoint reactions, being restricted in the objective specificity, etc.. They stress that we should sum up a series of regularities for clinical application (early diagnosis), and conduct profound research on its underlying mechanism in the coming days.