Possible Positive Selection for an Arsenic-Protective Haplotype in Humans

Background: Arsenic in drinking water causes severe health effects. Indigenous people in the South American Andes have likely lived with arsenic-contaminated drinking water for thousands of years. Inhabitants of San Antonio de los Cobres (SAC) in the Argentinean highlands generally carry an AS3MT (the major arsenic-metabolizing gene) haplotype associated with reduced health risks due to rapid arsenic excretion and lower urinary fraction of the monomethylated metabolite.Objectives: We hypothesized an adaptation to high-arsenic living conditions via a possible positive selection for protective AS3MT variants and compared AS3MT haplotype frequencies among different indigenous groups.Methods: Indigenous groups we evaluated were a) inhabitants of SAC and villages near Salta in northern Argentina (n = 346), b) three Native American populations from the Human Genome Diversity Project (HGDP; n = 25), and c) five Peruvian populations (n = 97). The last two groups have presumably lower historical exposure to arsenic.Results: We found a significantly higher frequency of the protective AS3MT haplotype in the SAC population (68.7%) compared with the HGDP (14.3%, p < 0.001, Fisher exact test) and Peruvian (50.5%, p < 0.001) populations. Genome-wide microsatellite (n = 671) analysis showed no detectable level of population structure between SAC and Peruvian populations (measure of population differentiation F_ST = 0.006) and low levels of structure between SAC and HGDP populations (F_ST < 0.055 for all pairs of populations compared).Conclusions: Because population stratification seems unlikely to explain the differences in AS3MT haplotype frequencies, our data raise the possibility that, during a few thousand years, natural selection for tolerance to the environmental stressor arsenic may have increased the frequency of protective variants of AS3MT. Further studies are needed to investigate this hypothesis.     

Picornavirus and enterovirus diversity with associated human diseases

Members of the Picornaviridae family are non-enveloped, positive-stranded RNA viruses with a 30 nm icosahedral capsid. This virus family exhibits a considerable amount of genetic variability driven both by mutation and recombination. Recently, three previously unknown human picornaviruses, namely the human Saffold cardiovirus, cosavirus and salivirus, have been identified in stools or respiratory samples from subjects presenting symptoms ranging from gastroenteritis to acute flaccid paralysis. However, these viruses were also frequently detected in asymptomatic subjects and their clinical relevance remains to be elucidated. The Enterovirus genus is a prototype example of the Picornaviridae heterogeneity at both genetic and phenotypic levels. This genus is divided into 10 species, seven of which contain human viruses, including three Rhinovirus species. Both human rhino- and enteroviruses are also characterized by high levels of genetic variability, as exemplified by the existence of over 250 different serotypes and the recent discovery of new enterovirus genotypes and the Rhinovirus C species. Despite their common genomic features, rhinoviruses are restricted to the respiratory tract, whereas the vast majority of enteroviruses infect the gastrointestinal tract and can spread to other organs, such as the heart or the central nervous system. Understanding the genetic determinants of such phenotypic diversity is an important challenge and a field for future investigation. Better characterization of these ubiquitous human pathogens may help to develop vaccines or antiviral treatments and to monitor the emergence of new strains.     

Gender representation amongst editorials boards in United Kingdom surgical specialty journals

Females remain under-represented in surgery in the United Kingdom and around the globe. Gender representation on journal editorial boards is one of the key metrics of gender representation within academic surgery. The aim of this study was to quantify gender representation within the editorial leadership of journals affiliated with UK surgical specialties. A web-based search for each of the UK surgical specialty associations was conducted, followed by identification of the endorsed journals for each one. As of August 2022, data on the gender of the editor-in-chief and other journal leadership positions, including associate, section, and deputy editors, were collated. Gender classification was completed using first-name recognition, verified by a web search using the name and institution provided. Managing editors without clinical backgrounds were excluded. Ten journals were identified for the following surgical specialties: General Surgery, Trauma and Orthopaedics, Neurosurgery, Cardiothoracic, Urology, Paediatric Surgery, Ear Nose and Throat, Oral and Maxillofacial, Plastic and Reconstructive Surgery, and Vascular Surgery. In total, 242 editorial positions were identified: 207 were held by males (82.8%) and 35 by females (17.2%). There were no female editors-in-chief. The average female proportion of editorial leadership per journal was 18.8%. One journal had no female editorial leadership representation. Overall, the number of females in editorial leadership positions is comparable to the current proportion of UK female consultant surgeons (13.7%). Journals with an under-representation of females in senior editorial leadership positions compared with the parent specialty should consider initiatives that will encourage diversity, promote greater gender parity, and champion female representation.     

Legacy genetics of Arachis cardenasii in the peanut crop shows the profound benefits of international seed exchange

The narrow genetics of most crops is a fundamental vulnerability to food security. This makes wild crop relatives a strategic resource of genetic diversity that can be used for crop improvement and adaptation to new agricultural challenges. Here, we uncover the contribution of one wild species accession, Arachis cardenasii GKP 10017, to the peanut crop (Arachis hypogaea) that was initiated by complex hybridizations in the 1960s and propagated by international seed exchange. However, until this study, the global scale of the dispersal of genetic contributions from this wild accession had been obscured by the multiple germplasm transfers, breeding cycles, and unrecorded genetic mixing between lineages that had occurred over the years. By genetic analysis and pedigree research, we identified A. cardenasii–enhanced, disease-resistant cultivars in Africa, Asia, Oceania, and the Americas. These cultivars provide widespread improved food security and environmental and economic benefits. This study emphasizes the importance of wild species and collaborative networks of international expertise for crop improvement. However, it also highlights the consequences of the implementation of a patchwork of restrictive national laws and sea changes in attitudes regarding germplasm that followed in the wake of the Convention on Biological Diversity. Today, the botanical collections and multiple seed exchanges which enable benefits such as those revealed by this study are drastically reduced. The research reported here underscores the vital importance of ready access to germplasm in ensuring long-term world food security.

Globally, most of humanity’s food is produced by only a few crop species, most of which have low genetic diversity (1–4). This presents a fundamental limitation to genetic improvement of crops and a key vulnerability for food security. Wild crop relatives have been used as a strategic source of diversity for plant breeders (4, 5). However, the agronomically unadapted phenotypes of wild species have hampered their use. For peanut (Arachis hypogaea L.), a crop with an exceptionally narrow genetic base (6, 7), the incorporation of wild relatives into breeding programs is further impeded by barriers in sexual compatibility between the tetraploid crop and its almost exclusively diploid wild relatives (8–10). This ploidy difference arose 5,000 to 10,000 y ago with the formation of the tetraploid species, via the hybridization and spontaneous polyploidization of the diploid “A” genome species, Arachis duranensis Krapov. & W.C. Greg. and the “B” genome species, Arachis ipaënsis Krapov. & W.C. Greg. The resultant tetraploid diversified into many peanut (A. hypogaea) landraces and varieties through artificial selection during cultivation. Peanut maintains almost-complete sets of chromosomes from the two ancestral diploid species thus having a genome almost entirely of “AABB” structure, a type of polyploid termed a segmental allotetraploid (2n = 4x = 40 chromosomes; genome size of ∼2.7 Gb; 6, 11, 12).Despite the difficulties presented by the ploidy barrier, considerable effort was invested during the 1960s in complex hybridizations between peanut and a diploid “A” genome wild species accession from Bolivia, Arachis cardenasii Krapov. & W.C. Greg. GKP 10017 [PI (Plant Introduction) 262141]. Interest in this accession had been stimulated by its identification as a source of very strong pest and disease resistance (13). Using two different hybridization schemes, two different research groups obtained fertile progeny which entered into breeding programs (see Results for more details). However, over time, the subsequent dispersal and development of the resultant germplasm, with multiple seed transfers, identification code reassignments, breeding cycles, and unrecorded mixing of lineages, left the actual genetic contribution of the wild species mostly forgotten, unrecorded, or undefined.Here, we reveal the previously unknown scale of the genetic influence of A. cardenasii GKP 10017 as a donor of pest and disease resistances to the world’s peanut crop. This study involved the sequencing and assembly of the genome of this wild species accession and genetic analysis and pedigree research of diverse peanut lines from around the world. Peanuts with genetic contributions from A. cardenasii were identified on every populated continent and in 30 countries. The cultivars provided improved food security for subsistence farmers and environmental and economic benefits.     

Gender diversity in chiropractic leadership: a cross-sectional study

BackgroundThe purpose of this cross-sectional study was to compare the number of males and females in leadership positions, and whether there is a relationship between gender and degrees held in those positions, within chiropractic academic institutions, national regulatory bodies and the most widely representative national professional associations in the United States and Canada.MethodsPublicly accessible websites from chiropractic institutions and organizations were used to collect data. Pearson χ² tests of independence were conducted to determine the relationship between gender (male vs. female) and other variables, including position (principal vs secondary), and chiropractic and other advanced professional degrees.ResultsA total of 107 leaders were identified across institutions and organizations. Under one-third of leaders (30.8%) were identified as female. Males were more likely to be in principal leadership roles (86.2%) and more likely to be in a secondary leadership position (62.8%).ConclusionMale leaders significantly outnumber female leaders in both principal and secondary leadership positions within American and Canadian chiropractic institutions. Strategies should be developed to include gender diversity within all chiropractic organizations.     

黄山地区储藏物孳生粉螨的群落组成及多样性分析

目的调查黄山地区储藏物中粉螨群落的物种组成和多样性。方法采集30种储藏物样本,分别进行粉螨的分离、计数及鉴定,并利用统计学方法进行多样性分析。结果30种储藏物中共检获粉螨19种,分别隶属于7科17属。粉螨的平均孳生密度为68.67只/克,物种丰富度指数为1.47,物种多样性指数为3.16,物种均匀度指数为1.07。结论储藏物中粉螨的孳生密度较大,其群落组成多样化。     

淮北地区不同生境中粉螨的生物多样性研究

目的探讨淮北地区不同环境粉螨群落结构。方法选取仓储环境(储藏物和/或地尘)、人居环境(卧室或学生宿舍中的床尘及地尘)和工作环境(纺织厂和/或制药厂工作车间中的地尘)等3类不同环境,采样点各40个,每个采样点各采集样本2份,每份l0g。过筛后留取尘渣,进行粉螨的采集、分类、鉴定及计数以及数据分析。结果3类不同环境共检获粉螨31种,隶属于7科21属,多样性分析结果表明:3类环境的粉螨平均孳生密度最高的是仓储环境,为57.2±6.2%,物种数为24,物种丰富指数为2.42,多样性指数为1.35,均匀度指数为0.97。结论3类不同环境中粉螨的孽十密度及多样性差异较大。     

贵州北部地区彝族、白族、穿青人和汉族头面部形态特征研究

目的：了解贵州北部地区彝族、白族、穿青人头面部形态特征。方法：采用整群抽取贵州北部地区彝族、白族、穿青人和汉族群体1581人（男性868人、女性713人）的头面部28项指标进行活体观察和比较。结果：各民族既有许多相同之处,又有各自不同的特点。结论：贵州北部地区彝族、白族、穿青人和汉族群体头面部形态特征具有丰富的多样性,这些特征对探讨贵州少数民族起源及其渊源关系具有重要意义。     

人K562细胞cDNA文库的扩增、纯化、鉴定和酵母细胞转化

目的:对预转化到大肠杆菌DH5 α中的人K562细胞cDNA文库进行扩增、纯化和鉴定并将文库质粒转化酵母细胞,为下一步的靶蛋白筛选做准备.方法:对K562细胞cDNA文库进行扩增,提取文库质粒,将文库质粒转化酵母Y187细胞,并用PCR和酶切鉴定转化结果.结果:成功的扩增人K562细胞cDNA文库、并验证了文库的多样性、将文库质粒成功转化酵母Y187细胞.结论:K562细胞cDNA文库的成功扩增、纯化、鉴定,为进一步的文库筛选奠定了基础.     

Usual Intake of Flavonoids Is Inversely Associated with Metabolic Syndrome in African American and White Males but Not Females in Baltimore City,Maryland, USA

Despite research that suggests flavonoids protect against metabolic syndrome (MetS) and evidence that intake of these compounds differs by race, knowledge about whether flavonoid–MetS associations vary among racial groups is limited. This study sought to estimate usual total flavonoid intake in African American and White adults and assess its sex- and sex/race-specific associations with MetS and its risk factors. Analysis of cross-sectional data from 1837 adults participating in the Healthy Aging in Neighborhoods of Diversity across the Life Span (HANDLS) study were analyzed. Usual total flavonoid intake was estimated using the NCI Method, and logistic regression measured its linkages with health outcomes. Among males overall and when stratified by race, odds of MetS and its risk factors low high-density lipoprotein cholesterol (HDL-C) and elevated glucose were lower at the 75th percentile of usual total flavonoid intake than at the 25th percentile (OR for MetS = 0.62; 95% CI = 0.53, 0.71). However, low HDL-C and elevated glucose were positively associated with usual flavonoid intake among females. The comparable associations by race within sex imply that the relationships between flavonoid and health outcomes may be evident across an array of intakes.