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In this experiment, seedlings as sources for shoot tips was assembled from the coconut research institute (CRI) of Chinese Academy of tropical agricultural sciences germplasm, Wenchang, Hainan, China. The shoot tips were cultured on Y3 medium to study the impact of ten concentrations of 2, 4-D and three vitamin mixtures on survival, death and development % on in vitro culture establishment stage of coconut (Cocos nucifera L.). The obtained results revealed that all 2,4-D concentrations 4,7, 75, 100, 120 and 140 mg/L + any vitamin mixture did not give any development and high concentrations of 2, 4-D increased the death %. In any case, it can be concluded that the rate of differences in survival, death and development percentages exhibited by 2, 4-D concentrations was more pronounced than the analogous ones resulted by vitamin mixtures. At any rate, utilizing of (2, 4-D at concentration 25 mg/L+ vitamin mixture 1 or 2) exhibited the greatest values of survival percentage and reduced death percentage. Just as, increased the percentages of development in in vitro culture establishment stage of coconut (Cocos nucifera L.) through seedlings shoot tip.
Comparative study of the genetic characteristics among three Acidithiobacillus caldus strains isolated from different typical environments in China was performed using a combination of molecular methods, namely sequencing analysis of PCR-amplified 16S rRNA genes and 16S-23S rRNA gene intergenic spacers (ITS), repetitive element PCR (rep-PCR), arbitrarily primed PCR (AP-PCR) fingerprinting and random amplified polymorphic DNA (RAPD). Both of the 16S rRNA gene and 16S-23S rRNA gene intergenic spacers sequences of the three strains exhibited small variations, with 99.9-100%, 99.7-100% identity respectively. In contrast, according to the analysis of bacterial diversity based on rep-PCR and AP-PCR fingerprinting, they produced highly discriminatory banding patterns, and the similarity values between them varied from 61.97% to 71.64%. RAPD analysis showed that banding profiles of their genomic DNA exhibited obvious differences from each other with 53.44-75% similarity. These results suggested that in contrast to 16S rRNA genes and 16S-23S rRNA gene intergenic spacers sequencing analysis, rep-PCR, AP-PCR fingerprinting and RAPD analysis possessed higher discriminatory power in identifying these closely related strains. And they could be used as rapid and highly discriminatory typing techniques in studying bacterial diversity, especially in differentiating bacteria within Acidithiobacillus caldus.
Powdery mildew, caused by Sphaerotheca fuliginea (Sf), is a widely distributed and destructive disease of greenhouse and field-grown cucumber plants and causes great yield loss. The objective of this research is to tentatively identify proteins that are differentially expressed in cucumber and are involved in modulating resistance to Sf-inoculation. We comparatively analyzed proteins differentially expressed in Sf-inoculated cucumber leaves using a pair of sister lines, B21-a-2-2-2 (highly susceptible) and B21-a-2-1-2 (highly resistant). To eliminate the interference of ribulose-1,5-bisphosphate carboxylase with low-abundance proteins, total proteins were pre-fractionated by 24 % polyethylene glycol (PEG) and the proteins from supernatant were analyzed by 2-DE. We were successful in establishing the identities of 20 proteins and those identified from the resistant line included proteins involved in metabolic, regulatory, and defense pathways. Our findings are discussed within the context of C. sativus–S. fuliginea interaction and tolerance to this pathogen. The results suggest that the resistance in cucumber is closely related to the enhancement of its primary metabolism, and ethylene modulated signaling in cucumber defense responses against powdery mildew, then defense-related proteins can be up-regulated as a result of altered gene expression.
Cats were injected with 2.4 mg/kg of tiletamine-zolazepam, 0.36 mg/kg of xylazine, and 0.8 mg/kg of tramadol, then blood was collected from their peripheral veins at 0.5, 1, 4, 8, 24, 48, 72, and 168 h after the injection. Before injection, the same cats were used as control group (0 h). Biochemical and haematological parameters were measured. The results revealed that the combination of the compounds produced good immobilisation, with minimal changes over time in biochemical and haematological parameters, which were within biologically acceptable limits.
This study investigated the concentrations of 11 metals in soils sampled in 1994 and 2014 from 17 cities throughout Anhui Province in China. Among the tested metals, Mn had the highest concentration and Hg the lowest. In the past 20 years, soil Cd, Co, Mn, and Cu concentrations demonstrated an increasing trend. In 1994, only Tongling City had a total metal concentration over 1,000 mg/kg, but in 2014, the seriously polluted cities also included Bengbu, Chizhou, Fuyang, Huannai, Huangshan, and Maanshan. Four assessment methods (two pollution indexes and two fuzzy mathematical models) were employed to investigate the soil environment quality of 17 cities. Environmental quality was determined to be Class I (excellent) or Class II (good) for each soil with single-factor index method, and most was identified as Class I for soils with the comprehensive index model. Different from the single-factor index method, the comprehensive index model concerned both the predominant index and average contribution of all pollution indices to integrated environmental quality. Using each of the two fuzzy mathematical methods (single-factor deciding and weighted average models), the environmental risks were determined to be Class I. However, divergence of the membership degree to each pollution class still occurred between the two methods. For fuzzy mathematical methods, membership functions were used to describe the limits between different pollution degrees, and different weights were allocated for the factors according to pollution contribution. Introduction of membership degree and weight of each factor to fuzzy mathematical models made the methods more reasonable in the field of environmental risk assessment.
Escherichia coli O157:H7 is well known for many foodborne outbreaks that lead to fatal infections in human being worldwide. The objective of this study was to develop a rapid and sensitive method for detection of EHEC O157:H7 from ground beef using a method that combined immunomagnetic separation (IMS) with loop-mediated isothermal amplifi cation (LAMP). The EHEC O157:H7 cells were separated with Dynabeads coated with antiEHEC O157:H7 after a short enrichment for 4 h. Then, EHEC O157:H7 was identifi ed by LAMP assay for amplifying and detecting the rfbE gene, which is highly conserved in all EHEC O157:H7 strains and exhibits strain-specific gene expression. The LAMP method results analyzed with real time turbidity measurements showed a high specificity and sensitivity, with a positive detection rate of amplifi cation of EHEC O157:H7 DNA diluted to a minimum equivalent concentration of 1.8 × 101 CFU/mL, which was 10 times more sensitive than the conventional PCR assay. The IMS followed with LAMP could capture and detect a bacterial concentration as low as 3×101 CFU/mL from the meat samples, which was close to the sensitivity of LAMP assay with pure culture. IMS combined with realistic LAMP method is a simple, rapid, highly specific gene amplifi cation technology that is suitable for implementing as a screening assay in basic laboratory and field test for detecting food contamination.
Brown cotton is a kind of naturally colored cotton. Because of less processing and little dying, it is more friendlier to environment than white cotton. For brown cotton, pigment accumulation in fiber is one of the most important characteristics. In this study, we selected a brown fiber line and a white fiber cultivar to determine the factor that affects the pigmentation in brown fiber. Accordingly, fibers were collected to verify the presence of PAs by p-dimethylaminocinnamaldehyde (DMACA) and toluidine blue O (TBO) staining. The PAs content and related genes expressions were determined. As a result, there were obvious differences on the aspect of PAs synthesis in fiber between white cotton and brown cotton. For white fiber, the PAs content reached maximum at 5 DPA, and then gradually decreased to zero. But for brown fiber, the PAs content was increased from 5 to 15 DPA stage, and reached the maximum at the 15 DPA stage, then gradually decreased from 15 to 40 DPA stage. On the contrary, in white cotton, PAs were synthesized in the whole developmental stage from 5 to 40 DPA. And PAs content in brown fiber were far more than that in white fiber, which may be the reason why the brown pigment accumulated in brown fiber.
Brown cotton is a kind of naturally colored cotton which accumulates brown pigment in fiber. In the experiment, the variations of DNA methylation and genes expression were studied during the development processes from 5 DPA to 25 DPA for brown fiber. By using the methylation-sensitive amplified polymorphism technique, we choose 66 pairs of selective-amplification primers to assess the status and levels of cytosine methylation. The hemimethylation of the external cytosine and the full methylation of the internal cytosine were scored. As a result, with the development of fiber from 5 DPA to 25 DPA, the ratios of the external hemimethylation and internal full methylation were gradually increased. In detail, at the stages of 5, 10, 15 and 25 DPA, the percentages of external hemimethylation were 8.29, 8.81, 9.77 and 10.09 %, the ratios of internal full methylation were 17.91, 19.20, 20.02 and 20.78 %, respectively. The development of brown fiber triggered the increase of methylated loci in the whole genome. For further analysis, we used cDNA-AFLP protocol to identify the specially expressed genes for further analysis. Totally, 30 polymorphic transcription-derived fragments (TDFs) were isolated and sequenced. By homologous alignment analysis, 19 TDFs were found similar with genes from cotton. Among them, the homologous genes of TDF5, TDF6, TDF10, TDF12, TDF17, TDF22, TDF23 and TDF25 were all from fiber. Furthermore, 13 TDFs were found to be homologous with reported functional genes.
The aim of this study was to investigate the effect and underlying mechanisms of short-term high-intensity sound exposure on guinea pigs to mimic the effects of non-lethal anti-riot weapons. A total of 92 male adult guinea pigs were exposed to high-intensity sound at 0 dB, 110 dB and 130 dB for 5 min. Basic clinical observation, repellent behaviour detection, peripheral blood routine examination, serum cortisol detection and hearing ability assessment were performed to analyse the functional changes after high intensity sound exposure. Meanwhile, routine haematoxylin and eosin staining, scanning electron microscopy and transmission electron microscopy were used to observe the structure of the cochlear tissue. To investigate the mechanisms underlying the tissue changes, the levels of apoptosis and caspase 3, 8 and 9 were detected using TUNEL staining and immunohistochemistry. After short-term exposure to high-intensity sound, the guinea pigs exhibited fear and agitation, increased repulsive behaviour, high serum cortisol and an increase in auditory threshold. The inner hair cells and outer hair cells exhibited degeneration. In addition, apoptosis was observed in the cochlear tissue. After short-term exposure to high-intensity sound, the guinea pigs exhibited not only stress reactions but also impaired hearing and signs of hair cell degeneration. Apoptosis in the cochlear tissue may play an important role in the functional and structural injuries caused by high-intensity sound.
Suaeda salsa L., a C3 euhalophytic herb, is native to saline soils, demonstrates high resistance to salinity stress. The effect of chilling stress on S. salsa under high salinity, particularly the change in unsaturated fatty acid content within membrane lipids, has not been investigated. After a 12 h chilling treatment (4°C) performed under low irradiance (100 μmol m⁻² s⁻¹), the chlorophyll contents, maximal photochemical efficiency of photosystem II (Fv/Fm) and actual PSII efficiency (ΦPSII) were determined. These measurements were significantly decreased in S. salsa leaves in the absence of salt treatment yet there were no significant changes with a 200 mM NaCl treatment. Chlorophyll contents, Fv/Fm and ΦPSII in S. salsa under 200 mM NaCl were higher than those without salt treatment. The unsaturated fatty acid content and the double bond index (DBI) of major membrane lipids of monogalactosyldiacylglycerols, digalactosyldiacylglycerols (DGDG), sulphoquinovosyldiacylglycerols and phosphatidylglycerols (PG) significantly increased following the chilling treatment (4°C) (with 12 h of low irradiance and 200 mM of NaCl). The DBI of DGDG and PG was decreased in the absence of the salt treatment. These results suggest that in the euhalophyte S. salsa, a 200 mM NaCl treatment increases chilling tolerance under conditions of low irradiance (100 μmol m⁻² s⁻¹).
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