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Garlic (Allium sativum L.) is an important cash crop in China. In the spring of 2018, stunted and chlorotic plants in some garlic fields were observed in Jinxiang, Shandong, and Feng Counties, Jiangsu Province, in China. The growth of symptomatic plants was weaker, with affected plants showing signs of apical chlorosis, wilting, and dieback. In the aerial part of the plant, the symptoms of root rot disease resembled nutrient deficiency or drought stress. The roots were shriveled and rotted, with reduced root density. According to survey, the incidence of root rot in each garlic planting area is as high as 35 to 40%, and once the disease occurs, the commodity value of garlic will be reduced. Generally speaking, fungal diseases are among the main biotic factors affecting garlic yield, particularly those caused by species of the genera Fusarium, Phytophthora, and Pythium. In order to identify the causal agent of this disease, symptomatic plants were collected from several regions of the main garlic producing areas in China, including Jinxiang County, Jiaxiang County in Shandong Province, and Fengxian County in Jiangsu Province. The garlic variety planted is Jinxiang white garlic, which is a local garlic variety. Samples of rotten roots were washed in tap water, surface sterilized in 1.5% sodium hypochlorite for 1 min followed by 75% ethanol for 30 s, rinsed with sterilized distilled water three times, and blotted dry on sterile filter paper. Pieces of infected root tissues (2 to 3 mm) were placed on potato dextrose agar (PDA) and kept at 28°C for 7 days. After the colonies were established on PDA, the fungal strains were purified by the hyphal-tip method. Five fungal isolates with similar morphology to each other were obtained, and isolate DS54-3 was chosen for the following experiment. The fungal colony grew within 5 days on PDA containing a full culture medium. Fungal colonies were white initially and then turned brown, and septate hyphae were 3.7 to 4.3 μm in diameter and branched at right angles with a constriction at the origin of the branch point. These characteristics are typical of the genus Rhizoctonia. Binucleate cells from five isolates were observed using a lactophenol aniline blue solution stain and matched Ceratobasidium morphological descriptions (Chen et al. 1985). The morphological characteristics of isolate DS54-3 were consistent with Ceratobasidium sp. (Sneh et al. 1991). Mycelia from five isolates grown on PDA were used for DNA extraction. The rDNA-ITS region was amplified using PCR with the universal fungal primers ITS1 and ITS4 (White et al. 1990). The purified products were separately sequenced in both directions using the same primer pair (Meza-Moller et al. 2014). ITS sequence analysis (GenBank accession no. MK733974) resulted in a 100% match for one accession of Ceratobasidium sp. AG-A (MF070683.1) by BLAST in the NCBI nucleotide database. The pathogenicity of isolate DS54-3 was then tested. For each conidial suspension,12 healthy 10-day-old garlic plants (about 5 cm) were used to conduct pathogenicity tests by wound inoculation, and the garlic varieties were the same as those collected in the field. The healthy garlic plants were inoculated with 5, 10, 20, 50, and 100 ml of conidial suspension (2.95 × 10⁷ conidia/ml) by the root irrigation method. Twenty plants were inoculated with the same volume of sterile water as a control for each conidial suspension. After 20 days, the leaves of all garlic seedlings inoculated with conidial suspension gradually turned yellow, similar to the symptoms observed during natural infection. After 40 days, the root system showed typical hollow and rotten symptoms, and eventually the plants withered and died, whereas the control plants remained healthy. The same colonial fungus was reisolated, thus fulfilling Koch’s postulates. This is the first report of Ceratobasidium sp. causing root rot disease of garlic in China.

Garlic (Allium sativum L.) is an important crop in China. In the spring of 2015, stunted and chlorotic plants in some garlic crops were observed in Jinxiang, Shandong Province, and Feng County, Jiangsu Province, in China. The growth of field symptomatic plants was weaker, with affected plants showing signs of apical chlorosis, wilting, and dieback. In the aerial part of the plant, the symptoms of pink root disease resembled nutrient deficiency or drought. The roots were pink and rotted, with reduced root density. To identify the causal agent of this disease, symptomatic plants were sampled. Samples of pink roots were washed in tap water, surface sterilized in 1.5% sodium hypochlorite for 1 min and then 75% ethanol for 30 s, rinsed with sterilized distilled water three times, and then blotted dry on sterile filter paper. Pieces of infected root tissues (2 to 3 mm) were cut and placed on potato dextrose agar (PDA) at 28°C for 7 days. After the colonies were established on PDA, the fungal strains were purified by the hyphal-tip method. Eight fungal isolates were obtained, and they were morphologically similar to each other, so H5 was chosen for the following experiment. Its colony grew slowly (5 cm in 10 days) on PDA plates, with abundant aerial mycelium, which were initially pale pink but changed to dark red with growth. Microconidia were not observed on PDA plates. For sporulation and pycnidia generation, isolate H5 was cultured on corn meal agar at 28°C under darkness for 7 days and then removed to combined 13-h photoperiod and 11-h darkness conditions for 7 days. It produced dark brown pycnidia (globose to subglobose, 160 to 230 µm) with brown setae 55 to 150 µm long. Pycnidiospores (4.0 to 5.0 × 1.5 to 2.0 µm) were oblong ovoid and oozed from rupture or through the ostiole. The morphological characteristics of H5 were consistent with S. terrestris (Boerema et al. 2004). Total genomic DNA was extracted from mycelium of isolate H5, and the large subunit region was amplified by polymerase chain reaction with the primer pair LROR and LR5 (de Gruyter et al. 2010). The sequence of isolate H5 was deposited in GenBank (MH046778), and a BLASTn search showed 100% similarity with several Setophoma terrestris sequences (GQ387587). The pathogenicity of isolate H5 was tested. Twelve healthy 10-day-old garlic sprouts (about 5 cm) were used to conduct pathogenicity tests by wound inoculation. Nine plants were inoculated with 10 ml of conidial suspension (1.2 × 10⁵ conidia/ml), respectively, by the root irrigation method, and another three plants were inoculated with the same volume of sterile water as a control. After 40 days, the leaves gradually yellowed, similar to leaf symptoms observed during natural infection. The roots showed typical symptoms of pink root, and finally the whole plant wilted and died, whereas the control plants remained healthy. The same colonial fungus was reisolated, thus fulfilling Koch’s postulates. The pathogen associated with pink root of various vegetables was hitherto considered to be Pyrenochaeta terrestris (H.N. Hansen, Gorenz, J.C. Walker & Larson or Phoma terrestris H.N. Hansen). To our knowledge, this is the first report of S. terrestris causing pink root of garlic in China.

To investigate the optimal growth condition of human fecal bacterial flora in vitro by comparing the effect of different carbohydrates as cultural media.Three fecal samples (1, 2, 3) were collected and inoculated into a single-stage chemostat system, in which starch medium (VI) and starch polysaccharide medium(XP) were used. Samples were collected for bacterial genomic DNA extraction and polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) analysis. Bacterial composition and short chain fatty acid (SCFA) were then analyzed.The single stage chemostat system reached steady after operating 8 days, when evaluated by the PCR-DGGE. Bacterial 16s rRNA high-throughput sequencing showed that the intestinal bacteria of these three volunteers was mainly composed of four bacterial phyla, namely, Bacteroidetes, Firmicutes, Proteobacteria and Actinobacteria. When the influence of bacterial abundance was considered, the similarity of bacterial composition between the original fecal samples to the harvested flora after culture was 0.847, 0.825, 0.968 in VI medium and 0.927, 0.926, 0.836 in XP medium, respectively. The similarity was decreased to 0.553, 0.580, 0.623 with VI medium and 0.617, 0.520, 0.574 with XP medium, when the number of bacterial species was considered. The variation of host individual also influenced the simulation. VI medium favored fecal sample 3, while XP medium more benefited sample 1 and 2. Bacteroides and Lachnospiraceae_incertae_sedis grew in both VI and XP medium. However, some species were only detected in VI medium and some were specifically found in the XP medium. The SCFA concentration in fermenters was 15-35 mmol/L, mainly propionate and butyrate.The chemostat system works for stimulating human gut bacterial flora in vitro. The bacterial composition is affected by different carbohydrate in the culture medium yet with close simulation higher than 80%.

Polymorphism (variable number of tandem repeats) in the second intron of the interleukin-1 receptor antagonist ( IL-1Ra) gene and two single nucleotide polymorphisms at positions −511 and +3954 of the IL-1β gene may be associated with an increased risk of rheumatoid arthritis (RA). This study used sex stratification to investigate a correlation of the three genetic polymorphisms with the risk of RA, on patients with RA and healthy controls. Polymerase chain reaction (PCR) and polymerase chain reaction–restriction fragment length polymorphism (PCR–RFLP) were performed. The frequencies of the IL-1β+ 3954 allele and genotype in female patients were significantly different compared with the controls; but in males, only the frequency of the IL-1β+ 3954 allele was different. The frequency of the IL-1RN genotype in patients was not statistically different compared with the controls; however, the frequency of IL-1RN allele in female patients was different. The association of the three polymorphisms with the susceptibility to RA appears to be significantly affected by gender.

This paper discusses the reasonable factors of parameters in CSEN design and has also raised some useful reasonable parameters concerned.

Specimens of 100 unrelated individuals were collected from Han ethnic group in Sichuan Province of China. DNA was extracted from blood specimens using Chelex 100 method (1).

A series of Ni(1−x)FexO (x=0, 0.015, 0.03, 0.05, and 0.1) bulk samples was synthesized by the chemical concentration-precipitation method. Phase composition analysis was carried out, which showed that trace amounts of ferromagnetic phase NiFe2O4 could not be detected by x-ray diffraction in these bulk samples with x≤0.03. When x>0.03, NiFe2O4 ferrite is detected easily. The magnetic properties of all the bulk samples were investigated by measuring their magnetization as a function of temperature and magnetic field. The results indicated that all the bulk samples sintered in air exhibited large room-temperature ferromagnetic behavior ascribed to a ferromagnetic impurity phase. Simultaneously, an exchange bias and training effect were also observed in all the bulk samples, suggesting the possibility of the existence of a strong ferromagnetic/antiferromagnetic exchange coupling in this kind of compound. Specifically, the exchange bias field could be tuned by changing the concentration of the Fe dopant.

Keshan disease (KD) is a cardiomyopathy endemic in certain areas of China, characterized by severe deterioration and multiple focal necrosis. In the present paper we describe abnormalities of the structure and function of myocardial mitochondria from patients with subacute Keshan disease. Activities of succinate dehydrogenase, succinic oxidase, cytochrome c oxidase, H(+)-ATPase and its sensitivity to oligomycin and the response of membrane potential to energization by ATP were significantly decreased. However, the spectrum of reduced-minus-oxidized cytochromes in patients' mitochondria showed no obvious difference in the content of cytochrome c oxidase (aa3). There was also a marked decrease in lipid fluidity of affected mitochondria, and an abnormal amount of moderately electron dense amorphous inclusions. Electron-microscopic x-ray microanalysis and exposure to protein digestion reagent demonstrated that these inclusions are not Ca3(PO4)2, but are, probably, proteinaceous in nature. Affected mitochondria had markedly decreased selenium content. The defects in myocardial mitochondria from patients with chronic Keshan disease were less extensive than those in patients with subacute Keshan disease. We propose that Keshan disease be classified as a form of "mitochondrial cardiomyopathy".