不同介入时间和不同疗程高压氧治疗对脑出血模型大鼠动物学行为及促血管新生因子表达的影响

摘要 目的：探讨不同介入时间和不同疗程高压氧治疗对脑出血大鼠动物学行为及促血管新生因子表达的影响。方法：240只SD大鼠随机分为假手术组、脑出血组、高压氧组,每组各80只。采用胶原酶诱导建立脑出血大鼠模型,建模成功后根据高压氧介入时间分为6 h介入组、1 d介入组、2 d介入组、3 d介入组等亚组。分别治疗1周、2周、3周、4周,采用Longa评分法、平衡木评分法、Berderson评分法评估大鼠动物学行为,采用qRT-PCR检测大鼠脑组织血管内皮生长因子（VEGF）、缺氧诱导因子-1α（HIF-1α）mRNA表达。结果：不同介入时间、不同疗程,脑出血组、高压氧组脑出血大鼠动物学行为评分、脑组织VEGF mRNA与HIF-1α mRNA表达均高于假手术组（P<0.05）。治疗1周、2周、3周、4周,不同介入时间高压氧组脑出血大鼠动物学行为评分低于脑出血组,脑组织VEGF mRNA、HIF-1α mRNA表达高于脑出血组（P<0.05）。高压氧介入时间越早,治疗疗程越长,脑出血大鼠动物学行为评分越低,脑组织VEGF mRNA、HIF-1α mRNA表达越高,差异均有统计学意义（P<0.05）。结论：高压氧治疗能够改善脑出血大鼠动物学行为、促进促血管新生因子表达,且以脑出血后6 h介入、疗程4周效果最佳。     

DNA水凝胶应用于环境样品快速检测的研究进展

DNA作为生物大分子既可以引导生物发育和生命机能活动,也可以被用作构筑纳米生物材料。DNA水凝胶可以制备成兼具DNA生物功能和水凝胶特质,应用于环境样品的分析检测。依据制备DNA水凝胶长链的方法,对比分析了聚合酶链反应、杂交链式反应、滚环扩增技术的制备,物理水凝胶和化学水凝胶的合成过程和改性方法技术特点;并结合环境样品浓度检测的变性响应特点,分析了荧光、比色、电化学法分析检测的技术要点和检测性能,与大型仪器分析方法相比该方法具有检出限低、检出范围广、检测时间快、测样成本偏低等特点,是一种方便快捷、应用前景广泛的方法;最后对其检出性能和经济性进行评估,并对其应用前景进行总结和展望。     

实验性延期再植牙大鼠模型组织学分析方法的建立

摘要 目的：建立延期再植牙大鼠模型并观察牙根不同部位预后特点,比较不同组织学分析方法的合理性,为相关临床、基础研究提供参考。方法：6周龄雄性SD大鼠10只,右侧上颌切牙脱位后延期再植,术后30 d 处死,分离上颌骨;利用micro CT从不同截面分析上颌切牙及牙周组织生理结构。切片后通过HE染色、MASSON染色、TRAP染色观察比较牙根不同部位愈合情况、破骨细胞分布情况。结果：大鼠切牙唇侧有釉质覆盖,腭侧牙骨质覆盖,且再植牙不同部位愈合情况、破骨细胞分布有差异,其牙根唇侧未见明显吸收,腭侧根中1/3相比根尖1/3和根颈1/3吸收范围更广、深度更深,破骨细胞分布数量更多,差异具有统计学意义（P<0.001）,提出了腭侧中1/3作为牙根吸收组织学分析区域的合理性。结论：本实验比较了再植牙大鼠模型牙根不同部位的愈合情况,提出了一种较为合理的组织学分析方法,能客观反映再植牙愈合方式,为进一步研究再植牙愈合机理提供了较好的研究模型。     

Bacterial communities in the rumen and feces of lactating Holstein dairy cows are not affected when fed reduced-fat dried distillers’ grains with solubles

Reduced-fat dried distillers’ grains with solubles (RF-DDGSs) are co-products of ethanol production and contain less fat than traditional distillers’ grains. The fat in corn is ~91% unsaturated, and it is toxic to rumen microorganisms so it could influence the composition of the rumen microbiome. It has been demonstrated that RF-DDGS is a suitable ration ingredient to support the high-producing dairy cow, and this feedstuff is a promising alternative protein source for lactating dairy cows. The current study aims to better understand the effect of RF-DDGS on the rumen and fecal bacterial composition in lactating dairy cows. Thirty-six multiparous (two or three), mid-lactation Holstein cows (BW = 680 ± 11 kg; 106 ± 27 DIM) were randomly assigned to two groups which were fed a control diet made up of corn, corn silage, and alfalfa hay supplemented with expeller soybean meal or with added RF-DDGS (20% of the DM) containing approximately 6.0% fat. Whole rumen contents (rumen fluid and digesta; esophageal tubing method) and feces (free-catch method) were collected on day 35 of the experimental period, after the 14-d acclimation period. Rumen contents and feces from each cow were used for DNA extraction. The bacterial community composition in rumen and fecal samples was assessed via the 16S rRNA gene by using the Illumina MiSeq sequencing platform. Bacteroidetes, Actinobacteria, and Firmicutes were the most abundant phyla in rumen contents. The fecal microbiota was dominated by the phyla Firmicutes and Bacteroidetes, as well as Actinobacteria and Chloroflexi. RF-DGGS increased bacterial richness, evenness, and Shannon diversity in both rumen and fecal samples and was associated with several taxa that had different abundance in treatment versus control comparisons. The RF-DGGS, however, did not significantly alter the bacterial community in the rumen or feces. In general, these findings demonstrated that dietary inclusion of RF-DDGS did not impose any serious short-term (within 30 days) health or production consequences, as would be expected. With this study, we present further evidence that inclusion of 20% (DM basis) RF-DDGS in the diet of lactating dairy cows can be done without consequence on the microbiome of the rumen.     

Growth curve,blood parameters and carcass traits of grass-fed Angus steers

The increasing demand for natural products is currently transforming the meat industry, making grass-fed and finished beef a valuable option for improving profits. However, the transformation of conventional operations to grass-fed systems comprises many modifications, such as logistical, technological, and financial that could be very complex and expensive, involving economic risk. Therefore, in this study, we analyzed the growth curve, critical economic traits, and carcass quality and finished characteristics over several consecutive years in closely related grass-fed and finished Angus steers, to reduce the genetic effect on the results. We found that grass-fed steers require around 188 additional days to reach the market weight (approx. 470 kg) and had approximately 70% less average daily gain compared to the grain-fed and finished steers. Regression analysis demonstrated an interaction between feed and age (P < 0.01); thus, individual regressions were fitted for each regimen style, obtaining almost perfect linear curves for both treatments, which could be straightforwardly used in practical situations due to its simplicity. Six of eight carcass traits were different between grain-fed and grass-fed and finished steers. Hot-carcass weight, dressing, back fat, and quality grade were superior in grain-fed individuals, contrarily to yield grade and ribeye area/carcass ratio, which were better in grass-fed and finished steers (P < 0.05).Interestingly, the meat tenderness was certainly low and similar in both treatments (P = 0.25), indicating the feasibility of producing tender meat with animals under a grass-fed diet. Nevertheless, according to the quality grade analysis, grain-fed carcasses were greater ranked compared to grass-fed bodies (P < 0.01), regardless of their same tenderness. The results will provide valuable information for better understanding beef cattle in grass-feeding finishing systems, especially from weaning to harvest. Additionally, the study will expand the knowledge about the quality of meat obtained from animals that received grass exclusively, becoming relevant information for economic evaluation and management decisions for grass-based cattle operations.     

Knowledge and attitudes regarding genetic testing among Jordanians: An approach towards genomic medicine

BackgroundThe twenty first century can be called the genomic era referring to the rapid development of genetics, and the beginning of genomic medicine. An initial step towards genomic medicine is to evaluate the knowledge and attitude towards genetic testing among different populations. The aims of this study were to assess the genetic knowledge and attitude towards genetic testing among the Jordanian population and patients with immune diseases. In addition, we evaluated the association between knowledge, attitude and several demographic factors of the population.MethodsThis study was performed using an online questionnaire that was distributed to respondents from different regions of Jordan.ResultsA total of 1149 participants were recruited from the Jordanian population. Overall factual genetic knowledge of the participants was good (65.4%), with education level, working or studying in a health-related field and household average monthly income being significant predictors of factual knowledge scores (P = 0.03, P < 0.001 and P < 0.001, respectively). However, factual knowledge results revealed that scores of questions related to diseases were significantly higher than scores of gene-related scientific facts (P < 0.01). Participants of our study reported to have low perceived knowledge on medical uses (39.5%) and social consequences (23.9%) of genetic testing. Regarding the participants’ attitudes, favorable attitudes towards genetic testing were prevailing (91.5%). Favorable attitudes were more prominent among higher educated participants, and participants with higher scores of factual knowledge.ConclusionDespite the fact that our Jordanian-based study revealed a good level of genetic knowledge as well as a favorable attitude towards genetic testing, we realized an imbalance of knowledge between gene-related scientific facts and disease-related concepts as well as between factual and perceived genetic knowledge, which indicates the necessity of increasing the awareness about genetic testing in order to ensure that individuals can take informed decisions that help in the employment of personalized medicine.     

Exploring human-animal host interactions and emergence of COVID-19: Evolutionary and ecological dynamics

The novel coronavirus disease (COVID-19) that emerged in December 2019 had caused substantial morbidity and mortality at the global level within few months. It affected economies, stopped travel, and isolated individuals and populations around the world. Wildlife, especially bats, serve as reservoirs of coronaviruses from which the variant Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) emerged that causes COVID-19. In this review, we describe the current knowledge on COVID-19 and the significance of wildlife hosts in its emergence. Mammalian and avian coronaviruses have diverse host ranges with distinct lineages of coronaviruses. Recombination and reassortments occur more frequently in mixed-animal markets where diverse viral genotypes intermingle. Human coronaviruses have evolved through gene gains and losses primarily in interfaces where wildlife and humans come in frequent contact. There is a gap in our understanding of bats as reservoirs of coronaviruses and there is a misconception that bats periodically transmit coronaviruses to humans. Future research should investigate bat viral diversity and loads at interfaces between humans and bats. Furthermore, there is an urgent need to evaluate viral strains circulating in mixed animal markets, where the coronaviruses circulated before becoming adapted to humans. We propose and discuss a management intervention plan for COVID-19 and raise questions on the suitability of current containment plans. We anticipate that more virulent coronaviruses could emerge unless proper measures are taken to limit interactions between diverse wildlife and humans in wild animal markets.     

News from the BSC No. 8

Abstract

In the 8th and following issues of News from the Biological Stain Commission (BSC), under the heading of Regulatory affairs, the BSC's International Affairs Committee will present information from a meeting held in Ghent, Belgium on 15–18 June 2009 concerning the progress achieved by the International Standards Organization Committee ISO/TC 212 Clinical Laboratory Testing and in Vitro Diagnostic Test Systems since the last meeting held in Vancouver, Canada in 2008. A note on the meaning and significance of E numbers found on the labels of foodstuffs and beverages sold for human consumption concludes this edition of News from the Biological Stain Commission.     

Do You Really Want to Know? Elementary Music Personnel and Potential in Utah

This is the second of two articles reporting the results of a study by the author regarding the status of elementary music education in the state of Utah. This article focuses on the qualifications of Utah's elementary music teachers (music certified, elementary classroom certified, artists-in-residence, volunteers, and paraprofessionals) and the conditions under which they teach. Interactions among teacher qualifications and teaching status are explored. Paraprofessionals play a significant role in Utah's elementary music programs. While over 90 percent of elementary schools in the United States provide regular music instruction taught by certified music specialists, less than 10 percent of Utah's elementary population receives such instruction. Nearly half of the elementary students in the state receive no designated music instruction beyond that provided by their regular elementary classroom teacher. The influence of school funding, No Child Left Behind and other accountability measures, high-stakes testing, urban/rural populations, and leadership are highlighted. Policy considerations are discussed.