The effect of post-treatment with caffeine on survival and UV-induced mutation frequencies in Chinese hamster and mouse lymphoma cells in vitro

The effect of post-treatment with caffeine on the survival of a number of cell lines after UV-irradiation has been studied. The mouse lymphoma cell lines P388 and L5178YS were sensitized by caffeine but only after UV doses of 50 erg/mm² and above. V79 cells also showed sensitization by caffeine but CHO cells and two cell lines YS and YR derived from Yoshida sarcoma of rats, sensitive and resistant to UV radiation, respectively, showed no effect.P388 and V79 cells were both mutable by UV, and caffeine, when studied at a single expression time (42–48 h) and at a single dose level (0.5 M and 0.75 M, respectively) suppressed the UV-induced mutation frequency in both cell lines. L51788YS cells although sensitized by caffeine showed no increase in frequency of thymidine-resistant (TdR^r) colonies when irradiated with UV.On more detaled examination, caffeine was found to delay the expression of UV-induced mutations inV79 cells, and the delay was dependent on the dose of caffine used. The effect on expression time was less when caffeine was present 0–48 h than when it was present throughout the post-irradiation incubation period. Similar results were obtained in P388 cells.The data are discussed in relation to those of other workers and to the concept that caffeine inhibits an error prone post-replication repair process in mammalian cells     

不同经皮克氏针内固定术治疗儿童GartlandⅡ、Ⅲ型肱骨髁上骨折疗效对比的回顾性分析

摘要 目的：对比不同经皮克氏针内固定术治疗GartlandⅡ、Ⅲ型肱骨髁上骨折患儿的治疗效果。方法：回顾性分析2017年3月~2020年3月期间我院收治的90例GartlandⅡ、Ⅲ型肱骨髁上骨折患儿的临床资料,根据治疗方式的不同,将患儿分为A组47例（采用切开复位经皮克氏针内固定术治疗）和B组43例（采用闭合复位经皮克氏针内固定术治疗）。观察两组疗效情况、围术期指标情况及并发症发生率。结果：A组、B组的优良率组间对比无统计学差异（P>0.05）。B组的手术时间、骨折愈合时间、住院时间均短于A组,术中失血量少于A组,组间对比差异有统计学意义（P<0.05）。两组术后并发症发生率比较差异无统计学意义（P>0.05）。结论：GartlandⅡ、Ⅲ型肱骨髁上骨折患儿采用闭合复位或切开复位经皮克氏针内固定术均可获得良好的手术效果,其中闭合复位在缩短手术时间、骨折愈合时间、住院时间和减少术中失血量方面更具备优势。     

切开与闭合复位空心钉内固定对移位股骨颈骨折患者骨折复位质量和髋关节功能的影响

摘要 目的：探讨切开与闭合复位空心钉内固定对移位股骨颈骨折患者骨折复位质量和髋关节功能的影响。方法：本研究为回顾性研究,选取98例移位股骨颈骨折患者的临床资料,根据手术方式的不同将患者分为A组（n=50,切开复位）和B组（n=48,闭合复位）,比较两组患者优良率、骨折复位质量、髋关节功能、围术期指标、术后并发症发生率和二次手术发生率。结果：A组患者术后6个月的优良率为78.00%（39/50）,高于B组的58.33%（28/48）（P<0.05）。两组术后负重下地时间、术中透视时间比较无差异（P>0.05）;B组手术时间、住院时间短于A组,术中出血量少于A组（P<0.05）。两组患者术后1个月、术后3个月、术后6个月髋关节功能Harris评分均较术前升高,且A组高于B组（P<0.05）。两组二次手术及并发症发生率比较无差异（P>0.05）。A组Ⅰ型、Ⅱ型的例数均多于B组,Ⅲ型例数少于B组（P<0.05）。结论：与闭合复位空心钉内固定相比,切开复位空心钉内固定虽损伤较大,但其术后骨折复位质量和髋关节功能改善效果更佳,且不增加并发症发生率和二次手术发生率。     

Viral impacts on honey bee populations: A review

Honey bee is vital for pollination and ecological services, boosting crops productivity in terms of quality and quantity and production of colony products: wax, royal jelly, bee venom, honey, pollen and propolis. Honey bees are most important plant pollinators and almost one third of diet depends on bee’s pollination, worth billions of dollars. Hence the role that honey bees have in environment and their economic importance in food production, their health is of dominant significance. Honey bees can be infected by various pathogens like: viruses, bacteria, fungi, or infested by parasitic mites. At least more than 20 viruses have been identified to infect honey bees worldwide, generally from Dicistroviridae as well as Iflaviridae families, like ABPV (Acute Bee Paralysis Virus), BQCV (Black Queen Cell Virus), KBV (Kashmir Bee Virus), SBV (Sacbrood Virus), CBPV (Chronic bee paralysis virus), SBPV (Slow Bee Paralysis Virus) along with IAPV (Israeli acute paralysis virus), and DWV (Deformed Wing Virus) are prominent and cause infections harmful for honey bee colonies health. This issue about honey bee viruses demonstrates remarkably how diverse this field is, and considerable work has to be done to get a comprehensive interpretation of the bee virology.     

A real‐time eco‐evolutionary dead‐end strategy is mediated by the traits of lineage progenitors and interactions with colony invaders

Evolutionary dead‐end strategies are characterized by short‐term productivity benefits and long‐term evolutionary costs. Here, I detail a real‐time dead‐end strategy associated with the behavioural traits of lineage progenitors in the social spider Anelosimus studiosus. Specifically, colony lineages founded by docile spiders were eight times more likely to suffer extinction, despite their superior reproductive output. However, when inquilines were experimentally removed from progenitor colonies, differences in extinction probability among lineages vanished. Similarly, among lineages founded by purely docile or aggressive individuals, the descendants of lineages with the highest reproductive output suffered the lowest survivorship, whereas lineages founded by a mixture of docile/aggressive lacked such a trade‐off. Finally, lineages with shorter progenitor‐descendant distances gained more inquilines and their descendants had lower survivorship, relative to more diffuse lineages. Overall, this study demonstrates how the traits of lineage progenitors and species interactions can unite to determine the fates of entire lineages.     

Antifungal effect of Penicillium metabolites against some fungi

Microorganisms are increasingly exploited as a source of new biological control agents. Genus Penicillium is a source of novel bioactive molecules which can be used as antifungal agents. The objective of this study was to evaluate the antifungal potential of Penicillium strains. Culture filtrates of two Penicillium species were tested for their antifungal potential by well diffusion assays. Filtrate of Penicillium isolates showed high antifungal effects on mycelial growth of Fusarium oxysporum, Fusarium solani, Macrophomina phaseolina, Aspergillus japonicus var aculeatus and Cladosporium cladosporioides. But Penicillium italicum inhibit the fungal growth from 45 to 68% as compared to Penicillium simplissimum (25–68%). However in case of A. japonicus var aculeatus, Penicillium spp. extracts were equally effective and reduce the colony growth up to 68%. However, P. simplissimum extract was least effective in case of M. phaseolina, where it decreased the colony growth only 25%.     

Temperature response,pathogenicity, seed infection and mutant evaluation against Macrophomina phaseolina causing charcoal rot disease of sesame

Charcoal rot caused by Macrophomina phaseolina is a serious disease of sesame in Pakistan. M. phaseolina sesame isolate was subjected to growth rate test at 10, 15, 20, 25, 30, 35 and 40°C. The optimum temperature for fungal growth and microsclerotia production was found to be 30–35°C. Gray to black, radial fungal colonies with intermediate mycelial growth and jet black oval to round microsclerotia were observed at this optimum range. M. phaseolina was found to be pathogenic against all the 18 tested plant species and this pathogenicity proved its necrophytic behavior. Seed infection efficiency of M. phaseolina was 100% with significant reduction in seed index. For two consecutive years 21 mutants/varieties were screened in the field for their reactions to charcoal rot disease. During 2007 three mutants NS11704S1, NS11304S2 and NS26004 were ranked as resistant while others were moderately resistant to highly susceptible. During 2008 all mutants showed a susceptible to highly susceptible reaction with variable disease reactions. All over screening results revealed that four mutants viz, NS13P1, NS163-1, NS270P1 and NS26004 showed about 50% stand with consistent performance during both years under optimum disease conditions and can be used to manage the disease following the disease management strategies, however in the future improvement for high seed yield along with resistance is a prerequisite for sustainable high production.     

Molecular defects identified by whole exome sequencing in a child with Fanconi anemia

Fanconi anemia is a rare genetic disease characterized by bone marrow failure, multiple congenital malformations, and an increased susceptibility to malignancy. At least 15 genes have been identified that are involved in the pathogenesis of Fanconi anemia. However, it is still a challenge to assign the complementation group and to characterize the molecular defects in patients with Fanconi anemia. In the current study, whole exome sequencing was used to identify the affected gene(s) in a boy with Fanconi anemia. A recurring, non-synonymous mutation was found (c.3971C>T, p.P1324L) as well as a novel frameshift mutation (c.989_995del, p.H330LfsX2) in FANCA gene. Our results indicate that whole exome sequencing may be useful in clinical settings for rapid identification of disease-causing mutations in rare genetic disorders such as Fanconi anemia.     

Phenotypic and genetic differences between opaque and translucent colonies of Vibrio alginolyticus

Many pathogens undergo phase variation between rugose and smooth colony morphology or between opaque and translucent colony morphology, which is mainly due to the variation in the surface polysaccharides. In this study, Vibrio alginolyticus ZJ-51 displayed phase variation between opaque, rugose colonies (Op) and translucent, smooth colonies (Tr). Unlike the vibrios reported previously, Tr cells of ZJ-51 enhanced biofilm formation and motility, but they did not differ from Op cells in the quantity of surface polysaccharides produced. Real time PCR was used to analyze the expression of the genes involved in polysaccharide biosynthesis, flagellar synthesis, and the AI-2 quorum-sensing system. The results revealed that the K-antigen capsule gene cluster (which consists of homologs to the cpsA-K in Vibrio parahaemolyticus) and O-antigen polysaccharide gene cluster (which contains homologs to the wza-wzb-wzc) were significantly more transcribed in Tr cells. The AI-2 quorum-sensing genes showed enhanced expression in the Tr variant which also exhibited greater expression of genes associated with polar flagellar biosynthesis. These results suggest that colony phase variation might affect the virulence and survival ability in the stressful environment inhabited by V. alginolyticus.     

An optimized technique for rapid genome modifications of Bacillus subtilis

The transformation efficiency of naturally competent Bacillus subtilis cells can be significantly increased using β recombinase binding sequences, as revealed by the results of this study. Plasmids containing different variations of these so called six-site-marker-cassettes were investigated. Furthermore, an optimized protocol for knock-out or knock-in mutations combining the Cre–lox-system and the six-sites is presented, which can be used for multiple genome modifications of B. subtilis.