scholarly journals A catalogue of 1,167 genomes from the human gut archaeome

Author(s):  
Cynthia Maria Chibani ◽  
Alexander Mahnert ◽  
Guillaume Borrel ◽  
Alexandre Almeida ◽  
Almut Werner ◽  
...  

AbstractThe human gut microbiome plays an important role in health, but its archaeal diversity remains largely unexplored. In the present study, we report the analysis of 1,167 nonredundant archaeal genomes (608 high-quality genomes) recovered from human gastrointestinal tract, sampled across 24 countries and rural and urban populations. We identified previously undescribed taxa including 3 genera, 15 species and 52 strains. Based on distinct genomic features, we justify the split of the Methanobrevibacter smithii clade into two separate species, with one represented by the previously undescribed ‘CandidatusMethanobrevibacter intestini’. Patterns derived from 28,581 protein clusters showed significant associations with sociodemographic characteristics such as age groups and lifestyle. We additionally show that archaea are characterized by specific genomic and functional adaptations to the host and carry a complex virome. Our work expands our current understanding of the human archaeome and provides a large genome catalogue for future analyses to decipher its impact on human physiology.

2020 ◽  
Author(s):  
Cynthia Maria Chibani ◽  
Alexander Mahnert ◽  
Guillaume Borrel ◽  
Alexandre Almeida ◽  
Almut Werner ◽  
...  

The human gut microbiome plays an important role in health and disease, but the archaeal diversity therein remains largely unexplored. Here we report the pioneering analysis of 1,167 non-redundant archaeal genomes recovered from human gastrointestinal tract microbiomes across countries and populations. We identified three novel genera and 15 novel species including 52 previously unknown archaeal strains. Based on distinct genomic features, we warrant the split of the Methanobrevibacter smithii clade into two separate species, with one represented by the novel Candidatus M. intestini. Patterns derived from 1.8 million proteins and 28,851 protein clusters coded in these genomes showed a substantial correlation with socio-demographic characteristics such as age and lifestyle. We infer that archaea are actively replicating in the human gastrointestinal tract and are characterized by specific genomic and functional adaptations to the host. We further demonstrate that the human gut archaeome carries a complex virome, with some viral species showing unexpected host flexibility. Our work furthers our current understanding of the human archaeome, and provides a large genome catalogue for future analyses to decipher its role and impact on human physiology.


Stanovnistvo ◽  
1999 ◽  
Vol 37 (1-4) ◽  
pp. 73-92
Author(s):  
Jelena Antonovic

Mass migration to urban areas constitutes the basic direct factor of the decline in rural population of Yugoslavia in the second half of the 20th century. Due to the characteristic migration patterns by age and sex, they have had a substantial impact on the change in age structure of rural population towards rapid demographic ageing. By inducing decline in fertility and an increase in mortality, the newly formed age structure is increasingly becoming one of the basic factors to further decline in population, or even the major factor to rural depopulation in the majority of regions. The paper analyzes changes in age structure of rural population in the FR of Yugoslavia and across its republics and provinces during the period from 1961 to 1991. The conditions prevailing during the last census (1991) are particularly highlighted. The author points to distinct differences in ageing of urban versus rural populations, and considerable regional differences at the achieved level of demographic age. Based on the main demographic age indicators (the share of five-year and larger age groups, average age, ageing index and movement in major age-specific contingents), the author concludes that the process of population ageing had taken place in both rural and urban populations, but was more intensive in villages (higher share of the aged, higher index of ageing and higher average age) during the period under review. The author points to distinct ageing of rural population in all republics and provinces. It was most prominent in central Serbia and Vojvodina, while being quite slow in Kosovo and Metohia and recorded mainly in between the last two censuses (1981-1991). Likewise, Kosovo and Metohia constitute the only major region of Yugoslavia in which rural population in 1991 is still demographically younger than the population in urban settlements. Rural versus urban population ageing was much more intensive in other major regions of the country, both from the base and from the apex of the age pyramid. In view of the minimal differences in fertility and mortality levels by type of settlement (particularly in central Serbia and Vojvodina), the author argues that the inherited age structure constitutes the main cause of rapid acceleration in rural population ageing in low fertility regions.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Cheryl Johnson ◽  
Moses Kumwenda ◽  
Jamilah Meghji ◽  
Augustine T. Choko ◽  
Mackwellings Phiri ◽  
...  

Abstract Background Despite the aging HIV epidemic, increasing age can be associated with hesitancy to test. Addressing this gap is a critical policy concern and highlights the urgent need to identify the underlying factors, to improve knowledge of HIV-related risks as well as uptake of HIV testing and prevention services, in midlife-older adults. Methods We conducted five focus group discussions and 12 in-depth interviews between April 2013 and November 2016 among rural and urban Malawian midlife-older (≥30 years) men and women. Using a life-course theoretical framework we explored how age is enacted socially and its implications on HIV testing and sexual risk behaviours. We also explore the potential for HIV self-testing (HIVST) to be part of a broader strategy for engaging midlife-older adults in HIV testing, prevention and care. Thematic analysis was used to identify recurrent themes and variations. Results Midlife-older adults (30–74 years of age) associated their age with respectability and identified HIV as “a disease of youth” that would not affect them, with age protecting them against infidelity and sexual risk-taking. HIV testing was felt to be stigmatizing, challenging age norms, threatening social status, and implying “lack of wisdom”. These norms drove self-testing preferences at home or other locations deemed age and gender appropriate. Awareness of the potential for long-standing undiagnosed HIV to be carried forward from past relationships was minimal, as was understanding of treatment-as-prevention. These norms led to HIV testing being perceived as a threat to status by older adults, contributing to low levels of recent HIV testing compared to younger adults. Conclusions Characteristics associated with age-gender norms and social position encourage self-testing but drive poor HIV-risk perception and unacceptability of conventional HIV testing in midlife-older adults. There is an urgent need to provide targeted messages and services more appropriate to midlife-older adults in sub-Saharan Africa. HIVST which has often been highlighted as a tool for reaching young people, may be a valuable tool for engaging midlife-older age groups who may not otherwise test.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Alexander Koliada ◽  
Vladislav Moseiko ◽  
Mariana Romanenko ◽  
Oleh Lushchak ◽  
Nadiia Kryzhanovska ◽  
...  

Abstract Background Evidence was previously provided for sex-related differences in the human gut microbiota composition, and sex-specific discrepancy in hormonal profiles was proposed as a main determinant of these differences. On the basis of these findings, the assumption was made on the role of microbiota in the sexual dimorphism of human diseases. To date, sex differences in fecal microbiota were demonstrated primarily at lower taxonomic levels, whereas phylum-level differences between sexes were reported in few studies only. In the present population-based cross-sectional research, sex differences in the phylum-level human gut microbiota composition were identified in a large (total n = 2301) sample of relatively healthy individuals from Ukraine. Results Relative abundances of Firmicutes and Actinobacteria, as determined by qRT-PCR, were found to be significantly increased, while that of Bacteroidetes was significantly decreased in females compared to males. The Firmicutes to Bacteroidetes (F/B) ratio was significantly increased in females compared to males. Females had 31 % higher odds of having F/B ratio more than 1 than males. This trend was evident in all age groups. The difference between sexes was even more pronounced in the elder individuals (50+): in this age group, female participants had 56 % higher odds of having F/B ratio > 1 than the male ones. Conclusions In conclusion, sex-specific differences in the phylum-level intestinal microbiota composition were observed in the Ukraine population. The F/B ratio was significantly increased in females compared to males. Further investigation is needed to draw strong conclusions regarding the mechanistic basis for sex-specific differences in the gut microbiota composition and regarding the role of these differences in the initiation and progression of human chronic diseases.


BMJ Open ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. e043228
Author(s):  
Lu Wang ◽  
Dongjie Xie ◽  
Jingrong Yu ◽  
Mark Momoh Koroma ◽  
Mengsi Qiu ◽  
...  

IntroductionNoroviruses are the leading cause of viral acute gastroenteritis affecting all age groups. Since 2014, the previous rarely reported GII.P17-GII.17 and recombinant GII.P16-GII.2 norovirus emerged, replacing GII.4 predominant genotype, causing increased outbreaks in China and other countries. Meanwhile, GII.4/2012 Sydney strain has re-emerged as the dominant variant in many places in 2015–2018. The role of herd immunity as the driving force during these new emerging or re-emerging noroviruses is poorly defined. Serological surveillance studies on community-based prospective cohort on norovirus are highly needed.Methods and analysesThis study will include 1000 out of 9798 participants aged 18 years and above from Caofeidian district, Tangshan city, northern China. Baseline data on sociodemographic characteristics and blood samples were collected in 2013–2014. Blood collection will be replicated annually throughout the cohort until 2023. Saliva samples were also collected in 2016. The seroprevalence and seroincidence of blockade antibodies against norovirus genotypes of GII.P17-GII.17, GII.P16-GII.2, the re-emerged GII.4/2012 and potential novel pandemic variants will be evaluated by ELISA. Associations between genotype blockade antibodies and sociodemographic factors and human histo-blood group antigens will be evaluated using univariate and multivariate analysis. The dynamics of herd immunity duration will be estimated in this longitudinal surveillance.Ethics and disseminationThe study has been approved by the Ethical Committees of the Staff Hospital of Jidong oil-field of China National Petroleum Corporation. This study will provide insight into the seroprevalence and seroincidence of noroviruses, and their relationships with sociodemographic characteristics and genetic susceptibility. It will also explain herd immunity of the emerged and re-emerged genotypes or variants. The study will further enable an understanding of the mechanism driving the replacement of norovirus genotypes. Research findings will be disseminated in peer-reviewed journals and at scientific meetings.


1994 ◽  
Vol 1 (4) ◽  
pp. 229-234 ◽  
Author(s):  
A Senthilselvan

OBJECTIVE: To examine the trends in hospitalization rates for atsthma in Saskatchewan from 1970 to 1989 and to investigate the differences in asthma hospitalization rates between rural and urban dwellers.DESIGN: Asthma hospitalization rates were calculated for the age groups O to 4, 5 to 9. 10 to 14, 15 to 24. 25 to 34. 35 to 49 and 50 to 64 years for the period between 1970 and 1989. Only the first admission in each year for each person was included in the analysis. As the classification of asthma changed in 1978. trends in asthma hospitalization rates were investigated separately for the periods 1970 to 1978 and 1979 to 1989. respectively. Rate ratios were obtained for male/female and rural/urban comparisons by fitting Poisson regression models.SETTING: The hospitalization data for respiratory diseases for the province of Saskatchewan were examined by age group, sex and place or residence.RESULT: No significant increases were observed in asthma hospitalization rates lrorn 1970 to 1978. In the period 1979 to 1989. asthma hospitalization rates increased significantly among children under four years from 4.31/1000 in 1979 to 7.04/1000 in 1989. Among children under 14 years. asthma hospitalization rates were greater in boys than in girls . The converse was true for adults aged 15 and above, with women having a higher hospitalization rate for asthma than men . In adults aged 35 and above. rural dwellers had higher hospitalization rates for asthma than urban dwellers throughout the study period. In other age groups, although rural dwellers had higher asthma hospitalization rates than did urban dwellers during 1970 to 1984. the differences disappered duri ng 1985 to 1989.CONCLUSION: Further studies are required to find reasons for the increase in asthma hospitalizations among young children under four years old and for the differences between rural and urban dwellers in the age group 35 years and above.


2014 ◽  
Vol 81 (1) ◽  
pp. 166-176 ◽  
Author(s):  
Francesca Bottacini ◽  
Mary O'Connell Motherway ◽  
Eoghan Casey ◽  
Brian McDonnell ◽  
Jennifer Mahony ◽  
...  

ABSTRACTBifidobacterium breveis a common and sometimes very abundant inhabitant of the human gut. Genome sequencing ofB. breveJCM 7017 revealed the presence of an extrachromosomal element, designated pMP7017 consisting of >190 kb, thus representing the first reported bifidobacterial megaplasmid.In silicocharacterization of this element revealed several genomic features supporting a stable establishment of the megaplasmid in its host, illustrated by predicted CRISPR-Cas functions that are known to protect the host against intrusion of foreign DNA. Interestingly, pMP7017 is also predicted to encode a conjugative DNA transfer apparatus and, consistent with this notion, we demonstrate here the conjugal transfer of pMP7017 to representative strains ofB. breveandB. longumsubsp.longum. We also demonstrate the presence of a megaplasmid with homology to pMP7017 in threeB. longumsubsp.longumstrains.


2021 ◽  
Vol 12 ◽  
Author(s):  
Wanmeng Xiao ◽  
Depei Gao ◽  
Hongju (Daisy) Chen ◽  
Yuting Qiao ◽  
Zhanshan (Sam) Ma ◽  
...  

Diversity scaling (changes) of human gut microbiome is important because it measures the inter-individual heterogeneity of diversity and other important parameters of population-level diversity. Understanding the heterogeneity of microbial diversity can be used as a reference for the personalized medicine of microbiome-associated diseases. Similar to diversity per se, diversity scaling may also be influenced by host factors, especially lifestyles and ethnicities. Nevertheless, this important topic regarding Chinese populations has not been addressed, to our best knowledge. Here, we fill the gap by applying a recent extension to the classic species–area relationship (SAR), i.e., diversity–area relationship (DAR), to reanalyze a large dataset of Chinese gut microbiomes covering the seven biggest Chinese ethnic groups (covering > 95% Chinese) living rural and urban lifestyles. Four DAR profiles were constructed to investigate the diversity scaling, diversity overlap, potential maximal diversity, and the ratio of local to global diversity of Chinese gut microbiomes. We discovered the following: (i) The diversity scaling parameters (z) at various taxon levels are little affected by either ethnicity or lifestyles, as exhibited by less than 0.5% differences in pairwise comparisons. (ii) The maximal accrual diversity (potential diversity) exhibited difference in only about 5% of pairwise comparisons, and all of the differences occurred in ethnicity comparisons (i.e., lifestyles had no effects). (iii) Ethnicity seems to have stronger effects than lifestyles across all taxon levels, and this may reflect the reality that China has been experiencing rapid urbanization in the last few decades, while the ethnic-related genetic background may change relatively little during the same period.


2021 ◽  
Author(s):  
Raissa Barreto Lima ◽  
Thaís Machado Belitardo de Carvalho ◽  
Matheus Campos Ribeiro de Souza ◽  
Lara Teixeira de Oliveira ◽  
Ana Carolina Pachêco de Menezes Rios ◽  
...  

Background: Neural tuberculosis is an infection of the central nervous system caused by the bacterium Mycobacterium tuberculosis. Bearing in mind that neural tuberculosis is the most severe form of extrapulmonary tuberculosis and results in significant morbidity and mortality rates, it is important to analyze its sociodemographic characteristics in Brazil. Objectives: To describe the sociodemographic characteristics of neural tuberculosis cases in Brazil in the period from 2010 to 2020. Design and Setting: Cross-sectional, retrospective, and descriptive study, carried out using data collected from the Notifiable Diseases Information System (SINAN) and the Hospital Information System (SIH / SUS) of confirmed cases and hospitalizations for neural tuberculosis. Methods: Variables used: region, sex, age group, color/race and year of service. Results: In the period from 2010 to 2020, the number of notified cases of meningoencephalic tuberculosis was 7.451, with mean cases per year of 677.36. The Southeast region was the most affected with 43.8% of the total cases, followed by the South and Northeast regions, with 24.1% and 20.1%, respectively. There was a wide predominance in individuals aged 30-39 years (42.8%) and in the age group 40-59 years (35.9%). The male sex was the most affected with 63.3% of the total. Conclusions: The study shows a predominance of cases in the South and Southeast regions, with a significant prevalence of males and age groups of 20- 59. This could be an alert for new prevention and health promotion strategies for the most affected groups.


2018 ◽  
Vol 47 (3) ◽  
pp. 604-622 ◽  
Author(s):  
Sanna Malinen ◽  
Teija Mankkinen

Although the need for emergency service volunteers is increasing internationally, it is challenging to attract and retain firefighters, who are highly trained and from whom sustained and potentially heavy time investment is required. To recruit and retain fire service volunteers, it is important to understand the barriers these volunteers face, and how these barriers relate to their attitudes and behavioral intentions. We surveyed 762 volunteer firefighters throughout Finland on these issues. Lack of time, conflict with work/school, and other work-related challenges were the most frequently reported barriers, and they were also rated as some of the most severe barriers. The number and severity of barriers were positively related to the volunteers’ absence and turnover intentions, and conflicts with family commitments. A higher number of reported barriers was also negatively related to volunteer satisfaction. No differences in barriers were found between rural and urban areas, or between gender and age groups. We discuss the findings in regard to relevant literature from other countries and conclude with practical implications.


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