First report of leaf blight caused by Stemphylium lycopersici on Salvia splendens in China

Salvia splendens is a popular ornamental plant in China with extensive potentials, including value in traditional Chinese medicine and in environmental restoration function (Li et al. 2008). In September 2019, leaf blight disease was observed on road side plants of S. splendens in Bayi park, Nanchang city, Jiangxi province, China. The typical symptoms appeared as irregular necrotic spots or leaf blight, accompanied by extensive scorch necrosis or ultimately defoliation. Small segments cut from diseased leaves were surface sterilized in a 2% sodium hypochlorite solution for 2 min and rinsed three times with sterile distilled water. Then, the samples were placed on potato dextrose agar (PDA) plates incubated at 25°C in darkness. Pure cultures were obtained by the hyphal tip method. Morphologically, all 11 colonies were identical to each other on PDA. Two strains, YZU 191468 and YZU 191481, were selected for further study and deposited in the Fungal Herbarium of Yangtze University (YZU), Jingzhou, Hubei, China. The 7-day-old colonies were circular, 53 to 56 mm in diameter, and consisted of white mycelium with a buff margin, and were cinnamon colored in the center of the reverse side. To examine conidial morphology, the mycelium was transferred onto potato carrot agar (PCA) and incubated at 23°C with a period of 8 h light/16 h dark for 7 days. Conidia were normally solitary or two in a chain, ellipsoid or long ellipsoid, beakless, 10 to 23×30 to 60 µm in size (n=50). Based on morphology, the isolates were consistent with Stemphylium lycopersici (Yamamoto 1960). To confirm the identification, genomic DNA was extracted from both isolates and used to amplify the internal transcribed spacer rDNA region (ITS), glyceraldehydes-3-phosphate dehydrogenase (GAPDH) and calmodulin (CAL) genes with primer pairs ITS5/ITS4, gpd1/gpd2, and CALDF1/CALDR2, respectively (Woudenberg et al. 2017). Sequences were deposited in GenBank with accession numbers OP564983 and OP564984 (ITS), OP892529 and OP892530 (GAPDH), OP584970 and OP584971 (CAL). A neighbor-joining tree was constructed with Mega 7.0 based on the combined dataset with 1,000 bootstrap replicates. The resulting phylogenetic tree showed that the strains from S. splendens clustered with S. lycopersici (CBS 122639 and CBS 124980) supported with 100% bootstrap values. The molecular analyses confirmed that the species causing leaf blight symptoms was S. lycopersici. To test pathogenicity, healthy leaves of S. splendens were surface sterilized and inoculated by mycelium blocks (6 mm in diameter) and spore suspension (1×106 spore/mL) of representative strains YZU 191468 and YZU 191481, respectively. Controls were inoculated with blocks of PDA and sterile water. Each strain was inoculated on three leaves of a plant. One clean plant was used as control. The test was replicated three times. After inoculation, the plants were covered with plastic bags and incubated in a greenhouse (25℃, 80 % relative humidity, 8 h light/16 h dark). After 5 days, the inoculated leaves exhibited dark brown spots with white mycelium, followed by withering of necrotic tissues. There were no symptoms observed on the controls. The fungal isolates inoculated leaves had the same morphological characteristics as the strains used for inoculation. S. lycopersici has been found on eggplant and Zinnia elegans in China (He et al. 2019; Yang et al. 2017). To the best of our knowledge, this is the first report of S. lycopersici causing leaf blight on S. splendens in China. This finding offers a new reference for the management and control of S. splendens leaf diseases in China.

[Reversible bilateral blindness associated with alcoholic ketoacidosis: a case report]

A 51-year-old male with a history of chronic alcoholism presented to the emergency department with an abrupt onset of complete bilateral blindness lasting for one hour. Funduscopic examination yielded unremarkable findings. Systemic evaluations revealed the presence of severe ketoacidosis. The patient spontaneously regained light perception after experiencing total blindness for 3 hours; however, he subsequently developed hypothermia and entered a state of shock. Following treatment with sodium bicarbonate and aggressive fluid resuscitation, his condition stabilized, and there was a rapid improvement in his visual acuity. The diagnosis of alcoholic ketoacidosis was established based on the patient's history of chronic alcohol abuse, physical examination findings, and blood analysis results.

Effects of L-arginine cardioplegia on myocardium

Infusion of L-arginine (a precursor of nitric oxide, NO) in cardioplegia was examined to test its effect on metabolism of myocardium after myocardial ischemia and reperfusion (IR). Twenty-eight patients undergoing valve replacement were involved and randomly divided into two groups: the control group (crystalloid cardioplegia) and the experimental group (crystalloid cardioplegia + L-arginine). Blood samples were taken both before aortic clamping and after aortic unclamping from right radial artery to measure the concentrations of NO2-/NO3-, lactic acid (LA), malondialdehyde (MDA), superoxide dismutase (SOD), and xanthine oxidase (XOD). In the control group, the NO2-/NO3- level decreased at aortic unclamping, and 30 min later, it decreased significantly as compared with that before aortic clamping (p < .05). In the experimental group, it increased at aortic unclamping (p < .05), and 60 min later, increased to the peak. Five, fifteen, and thirty min after aortic unclamping, the concentrations of LA and MDA in the experimental group were lower than those in the control group (p < .05). Thirty and sixty min after aortic unclamping, the concentrations of SOD remained higher in the experimental group than those in the control group (p < .05). There was no difference between groups in the concentrations of XOD. The addition of L-arginine to the cardioplegia can protect the myocardium from injury by releasing nitric oxide.