153 research outputs found
Blood pressure variation and hypertension rates in a pre-modernized Bedouin population: data from tribes of the Sinai Peninsula (Egypt)
Au cours du 20e s., la société bédouine est passée d'un mode de vie d'éleveurs seminomades à un mode de vie plus occidental, ce qui a entraîné une augmentation des facteurs de risque au regard de maladies mettant la vie en danger, comme le démontrent des études récentes sur l'hypertension et l'obésité dans les groupes bédouins. Face à cette transition épidémiologique, il nous a paru important d'analyser, chez les Bédouins, les valeurs de la tension artérielle (BP) et les données anthropométriques associées, avant que les tribus ne soient soumises à la modernisation. Les tribus Towara de la péninsule du Sinaï représentent le mode de vie bédouin traditionnel. L'échantillon étudié comprend 318 hommes et 91 femmes âgés de 17 à 85 ans. La valeur moyenne de la tension artérielle est de 121/81 pour les hommes et de 111/76 pour les femmes. Le taux global d'hypertension (HTN), défini comme la proportion d'individus ayant une tension systolique >/ = 140 et/ou une tension diastolique>/ = 90 mmHg est de 12 % pour les hommes et de 4 % pour les femmes. L'indice de masse corporelle est de 20kg/m2 pour les deux sexes. Les valeurs de la tension et le taux d'hypertension sont peu élevés chez les Towara en comparaison avec les autres groupes bédouins et arabes du Moyen-Orient. Les comparaisons inter-tribales ne concernent que les adultes jeunes (20-39 ans pour les hommes et 17-39 ans pour les femmes). Les femmes de la tribu Muzeina présentent des valeurs de tension artérielle exceptionnellement basses (108/76 mmHg) alors que les hommes de cette tribu (tension moyenne de 122/80 mmHg) ne se distinguent pas des autres groupes Towara. Dans les 4 groupes d'hommes étudiés, le taux global d'hypertension varie de 6 % à 20 %. Il n'a pas été possible de démontrer que la tension et le taux d'hypertension augmentait avec l'âge, bien que les hommes Towara les plus jeunes (17-19 ans) présentent, pour ces deux caractères, des valeurs moins élevées que les hommes du groupe le plus âgé (50+) : 117/79 contre 125/86 et 5 % contre 19 %. Les échantillons de femmes ne permettent aucune comparaison ; signalons néanmoins que 3 femmes Towara seulement étaient atteintes d'hypertension. Les valeurs peu élevées de la tension artérielle et du taux d'hypertension reflètent le mode de vie traditionnel de la population Towara et peuvent servir de référence pour effectuer des comparaisons tout au long du processus de modernisation.During the 20th century Bedouin society has shifted from semi-nomad pastoralism toward a more Western life style, whilst accumulating risk factors for life threatening diseases. This is evident from recent reports of hypertension and obesity in Bedouin groups. In face of this epidemiological transition, it is important to document blood pressure (BP) values and related anthropometrics of Bedouin tribes prior to considerable exposure to modernization. The Towara tribes of the Sinai Peninsula represent traditional Bedouin subsistence and culture. The Towara sample includes 318 men and 91 women, age 17 up to 85 years. Mean BP values of Towara men and women are 121/81 and 111/76, respectively. The overall rates of hypertension (HTN, defined as the percent of persons with systolic BP >/= 140 and/or diastolic BP >/= 90 mmHg) are 12% for males and 4% for females. BMI is 20 kg/m2 for both sexes. Blood pressure values and HTN rates of the Towara males and females are found to be low when compared to other Bedouin and Arab groups of the Middle East. Inter-tribal comparison considers only young adults: ages 20-39 years for men and 17-39 for women. Females of the Muzeina tribe have exceptionally low BP values: 108/76 mmHg, while Muzeina males (BP: 122/80 mmHg) are not distinguishable from other Towara groups. HTN rates in the 4 male tribal groups range between 6% and 20%. No consistent age-dependent increase is evident for males in either BP or HTN rates, although for both traits the youngest Towara men (17-19 years) have lower values than the oldest group (50+): 117/79 vs. 125/86, and 5% vs. 19%. Female samples do not allow for effective comparison, however only 3 Towara women were found to have HTN. The low values of BP and HTN rates reflect the traditional subsistence of Towara population and can serve as a reference for comparison along the modernization process
Late Pleistocene human genome suggests a local origin for the first farmers of central Anatolia
Anatolia was home to some of the earliest farming communities. It has been long debated whether a migration of farming groups introduced agriculture to central Anatolia. Here, we report the first genome-wide data from a 15,000-year-old Anatolian hunter-gatherer and from seven Anatolian and Levantine early farmers. We find high genetic continuity (~80–90%) between the hunter-gatherers and early farmers of Anatolia and detect two distinct incoming ancestries: an early Iranian/Caucasus related one and a later one linked to the ancient Levant. Finally, we observe a genetic link between southern Europe and the Near East predating 15,000 years ago. Our results suggest a limited role of human migration in the emergence of agriculture in central Anatolia
Evolutionary changes in the genome of Mycobacterium tuberculosis and the human genome from 9000 years BP until modern times
The demonstration of Mycobacterium tuberculosis DNA in ancient skeletons gives researchers an insight
into its evolution. Findings of the last two decades sketched the biological relationships between the
various species of tubercle bacilli, the time scale involved, their possible origin and dispersal. This paper
includes the available evidence and on-going research. In the submerged Eastern Mediterranean
Neolithic village of Atlit Yam (9000 BP), a human lineage of M. tuberculosis, defined by the TbD1 deletion
in its genome, was demonstrated. An infected infant at the site provides an example of active tuberculosis
in a human with a naïve immune system. Over 4000 years later tuberculosis was found in Jericho.
Urbanization increases population density encouraging M. tuberculosis/human co-evolution. As susceptible
humans die of tuberculosis, survivors develop genetic resistance to disease. Thus in 18th century
Hungarian mummies from V ac, 65% were positive for tuberculosis yet a 95-year-old woman had clearly
survived a childhood Ghon lesion.
Whole genome studies are in progress, to detect changes over the millennia both in bacterial virulence
and also host susceptibility/resistance genes that determine the NRAMP protein and Killer Cell
Immunoglobulin-like Receptors (KIRs). This paper surveys present evidence and includes initial findings.The contribution made by our many collaborators, researchers
and students is gratefully acknowledged. Special acknowledgement
is due to Dr Angela Gernaey (deceased) who helped pioneer the
early mycolic acid work on the bison bone
Trabecular architecture in the thumb of Pan and Homo: implications for investigating hand use, loading, and hand preference in the fossil record
Objectives: Humans display an 85–95% cross-cultural right-hand bias in skilled tasks, which is considered a derived behavior because such a high frequency is not reported in wild non-human primates. Handedness is generally considered to be an evolutionary byproduct of selection for manual dexterity and augmented visuo-cognitive capabilities within the context of complex stone tool manufacture/use. Testing this hypothesis requires an understanding of when appreciable levels of right dominant behavior entered the fossil record. Because bone remodels in vivo, skeletal asymmetries are thought to reflect greater mechanical loading on the dominant side, but incomplete preservation of external morphology and ambiguities about past loading environments complicate interpretations. We test if internal trabecular bone is capable of providing additional information by analyzing the thumb of Homo sapiens and Pan.
Materials and methods: We assess trabecular structure at the distal head and proximal base of paired (left/right) first metacarpals using micro-CT scans of Homo sapiens (n?=?14) and Pan (n?=?9). Throughout each epiphysis we quantify average and local bone volume fraction (BV/TV), degree of anisotropy (DA), and elastic modulus (E) to address bone volume patterning and directional asymmetry.
Results: We find a right directional asymmetry in H. sapiens consistent with population-level handedness, but also report a left directional asymmetry in Pan that may be the result of postural and/or locomotor loading.
Conclusion: We conclude that trabecular bone is capable of detecting right/left directional asymmetry, but suggest coupling studies of internal structure with analyses of other skeletal elements and cortical bone prior to applications in the fossil record
Macrophage-Induced Lymphangiogenesis and Metastasis following Paclitaxel Chemotherapy Is Regulated by VEGFR3
While chemotherapy strongly restricts or reverses tumor growth, the response of host tissue to therapy can counteract its anti-tumor activity by promoting tumor re-growth and/or metastases, thus limiting therapeutic efficacy. Here, we show that vascular endothelial growth factor receptor 3 (VEGFR3)-expressing macrophages infiltrating chemotherapy-treated tumors play a significant role in metastasis. They do so in part by inducing lymphangiogenesis as a result of cathepsin release, leading to VEGF-C upregulation by heparanase. We found that macrophages from chemotherapy-treated mice are sufficient to trigger lymphatic vessel activity and structure in naive tumors in a VEGFR3-dependent manner. Blocking VEGF-C/VEGFR3 axis inhibits the activity of chemotherapy-educated macrophages, leading to reduced lymphangiogenesis in treated tumors. Overall, our results suggest that disrupting the VEGF-C/VEGFR3 axis not only directly inhibits lymphangiogenesis but also blocks the pro-metastatic activity of macrophages in chemotherapy-treated mice
Detection and Molecular Characterization of 9000-Year-Old Mycobacterium tuberculosis from a Neolithic Settlement in the Eastern Mediterranean
Background: Mycobacterium tuberculosis is the principal etiologic agent of human tuberculosis. It has no environmental reservoir and is believed to have co-evolved with its host over millennia. This is supported by skeletal evidence of the disease in early humans, and inferred from M. tuberculosis genomic analysis. Direct examination of ancient human remains for M. tuberculosis biomarkers should aid our understanding of the nature of prehistoric tuberculosis and the host/pathogen relationship.Methodology/Principal Findings: We used conventional PCR to examine bone samples with typical tuberculosis lesions from a woman and infant, who were buried together in the now submerged site of Atlit-Yam in the Eastern Mediterranean, dating from 9250-8160 years ago. Rigorous precautions were taken to prevent contamination, and independent centers were used to confirm authenticity of findings. DNA from five M. tuberculosis genetic loci was detected and had characteristics consistent with extant genetic lineages. High performance liquid chromatography was used as an independent method of verification and it directly detected mycolic acid lipid biomarkers, specific for the M. tuberculosis complex.Conclusions/Significance: Human tuberculosis was confirmed by morphological and molecular methods in a population living in one of the first villages with evidence of agriculture and animal domestication. The widespread use of animals was not a source of infection but may have supported a denser human population that facilitated transmission of the tubercle bacillus. The similarity of the M. tuberculosis genetic signature with those of today gives support to the theory of a long-term co-existence of host and pathogen
- …