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1.
Sci Rep ; 14(1): 11895, 2024 05 28.
Article de Anglais | MEDLINE | ID: mdl-38806487

RÉSUMÉ

Etruria contained one of the great early urban civilisations in the Italian peninsula during the first millennium BC, much studied from a cultural, humanities-based, perspective, but relatively little with scientific data, and rarely in combination. We have addressed the unusual location of twenty inhumations found in the sacred heart of the Etruscan city of Tarquinia, focusing on six of these as illustrative, contrasting with the typical contemporary cremations found in cemeteries on the edge of the city. The cultural evidence suggests that the six skeletons were also distinctive in their ritualization and memorialisation. Focusing on the six, as a representative sample, the scientific evidence of osteoarchaeology, isotopic compositions, and ancient DNA has established that these appear to show mobility, diversity and violence through an integrated bioarchaeological approach. The combination of multiple lines of evidence makes major strides towards a deeper understanding of the role of these extraordinary individuals in the life of the early city of Etruria.


Sujet(s)
Archéologie , Italie , Humains , Histoire ancienne , Mâle , ADN ancien/analyse , Femelle
2.
Eur J Trauma Emerg Surg ; 44(6): 805-810, 2018 Dec.
Article de Anglais | MEDLINE | ID: mdl-26683569

RÉSUMÉ

PURPOSE: To evaluate the feasibility of a new protocol, Chest Abdominal-Focused Assessment Sonography for Trauma (CA-FAST), during the primary survey and to estimate its diagnostic accuracy when compared with thoracoabdominal computed tomography (CT) scan. METHODS: A prospective accuracy study was performed from November 2012 to November 2013 at the Emergency Department. Only adult trauma patients who underwent a CA-FAST examination prior to a thoracoabdominal CT scan were enrolled. In addition to standard patterns detected by Extended-FAST (E-FAST) such as pneumothorax (PTX), hemothorax (HTX), pericardial and intraabdominal effusion, CA-FAST protocol also included the research of lung contusions (LCs). RESULTS: Six hundred and one patients were enrolled. The mean time for protocol execution was 7 ± 3 min. Chest ultrasonography showed the following results (all p < 0.001): LCs sensitivity 59 %, specificity 98 %, positive predictive value (PPV) 92 %, negative predictive value (NPV) 86 %, accuracy 87 %; PTX sensitivity 84 %, specificity 98 %, PPV 93 %, NPV 95 %, accuracy 95 %; HTX sensitivity 82 %, specificity 97 %, PPV 87 %, NPV 95 %, accuracy 94 %. The standard 4-views FAST examination showed a diagnostic accuracy of 91 % with a sensitivity of 75 %, specificity of 96 %, PPV of 81 % and NPV of 94 %. CONCLUSION: According to our results CA-FAST protocol proved to be a rapid bedside method, with good accuracy and high NPV in detection of ultrasonographic patterns suggestive of serious injury in trauma patients; moreover, the additional research of LCs did not cause a delay in the diagnosis. Ultrasonography should be used as initial investigation during the primary survey, sending to further diagnostic studies (CT scan) only those patients not clearly classified.


Sujet(s)
Traumatismes de l'abdomen/imagerie diagnostique , Blessures du thorax/imagerie diagnostique , Plaies non pénétrantes/imagerie diagnostique , Protocoles cliniques , Service hospitalier d'urgences , Femelle , Évaluation d'un traumatisme par échographie ciblée , Humains , Italie , Mâle , Adulte d'âge moyen , Études prospectives , Sensibilité et spécificité , Tomodensitométrie
3.
Oncogene ; 36(33): 4682-4691, 2017 08 17.
Article de Anglais | MEDLINE | ID: mdl-28394338

RÉSUMÉ

High-risk and MYCN-amplified neuroblastomas are among the most aggressive pediatric tumors. Despite intense multimodality therapies, about 50% of these patients succumb to their disease, making the search for effective therapies an absolute priority. Due to the important functions of poly (ADP-ribose) polymerases, PARP inhibitors have entered the clinical settings for cancer treatment and are being exploited in a variety of preclinical studies and clinical trials. PARP inhibitors based combination schemes have also been tested in neuroblastoma preclinical models with encouraging results. However, the expression of PARP enzymes in human neuroblastoma and the biological consequences of their inhibition remained largely unexplored. Here, we show that high PARP1 and PARP2 expression is significantly associated with high-risk neuroblastoma cases and poor survival, highlighting its previously unrecognized prognostic value for human neuroblastoma. In vitro, PARP1 and 2 are abundant in MYCN amplified and MYCN-overexpressing cells. In this context, PARP inhibitors with high 'PARP trapping' potency, such as olaparib or talazoparib, yield DNA damage and cell death preceded by intense signs of replication stress. Notwithstanding the activation of a CHK1-CDC25A replication stress response, PARP-inhibited MYCN amplified and overexpressing cells fail to sustain a prolonged checkpoint and progress through mitosis in the presence of damaged DNA, eventually undergoing mitotic catastrophe. CHK1-targeted inhibition of the replication stress checkpoint exacerbated this phenotype. These data highlight a novel route for cell death induction by PARP inhibitors and support their introduction, together with CHK1 inhibitors, in therapeutic approaches for neuroblastomas with high MYC(N) activity.


Sujet(s)
Réplication de l'ADN/effets des médicaments et des substances chimiques , Mitose/effets des médicaments et des substances chimiques , Protéine du proto-oncogène N-Myc/métabolisme , Neuroblastome/traitement médicamenteux , Poly (ADP-Ribose) polymerase-1/métabolisme , Inhibiteurs de poly(ADP-ribose) polymérases/usage thérapeutique , Poly(ADP-ribose) polymerases/métabolisme , Apoptose/effets des médicaments et des substances chimiques , Lignée cellulaire tumorale , Prolifération cellulaire/effets des médicaments et des substances chimiques , Checkpoint kinase 1/métabolisme , Enfant , Humains , Estimation de Kaplan-Meier , Protéine du proto-oncogène N-Myc/génétique , Poly (ADP-Ribose) polymerase-1/génétique , Inhibiteurs de poly(ADP-ribose) polymérases/administration et posologie , Poly(ADP-ribose) polymerases/génétique
4.
Cell Death Dis ; 5: e1120, 2014 Mar 13.
Article de Anglais | MEDLINE | ID: mdl-24625979

RÉSUMÉ

Apoptotic cell death is an integral part of cell turnover in many tissues, and proper corpse clearance is vital to maintaining tissue homeostasis in all multicellular organisms. Even in tissues with high cellular turnover, apoptotic cells are rarely seen because of efficient clearance mechanisms in healthy individuals. In Caenorhabditis elegans, two parallel and partly redundant conserved pathways act in cell corpse engulfment. The pathway for cytoskeletal rearrangement requires the small GTPase CED-10 Rac1 acting for an efficient surround of the dead cell. The CED-10 Rac pathway is also required for the proper migration of the distal tip cells (DTCs) during the development of the C. elegans gonad. Parkin, the mammalian homolog of the C. elegans PDR-1, interacts with Rac1 in aged human brain and it is also implicated with actin dynamics and cytoskeletal rearrangements in Parkinsons's disease, suggesting that it might act on engulfment. Our genetic and biochemical studies indicate that PDR-1 inhibits apoptotic cell engulfment and DTC migration by ubiquitylating CED-10 for degradation.


Sujet(s)
Apoptose , Caenorhabditis elegans/enzymologie , Phagocytose , Ubiquitin-protein ligases/métabolisme , Animaux , Apoptose/effets des médicaments et des substances chimiques , Caenorhabditis elegans/effets des médicaments et des substances chimiques , Caenorhabditis elegans/génétique , Protéines de Caenorhabditis elegans/génétique , Protéines de Caenorhabditis elegans/métabolisme , Mouvement cellulaire , Cellules HEK293 , Humains , Mutation , Phagocytose/effets des médicaments et des substances chimiques , Proteasome endopeptidase complex/métabolisme , Inhibiteurs du protéasome/pharmacologie , Protéolyse , Transduction du signal , Transfection , Ubiquitin-protein ligases/génétique , Ubiquitination , Protéines G rac/génétique , Protéines G rac/métabolisme , Protéine G rac1/métabolisme
5.
J Hum Evol ; 64(1): 83-92, 2013 Jan.
Article de Anglais | MEDLINE | ID: mdl-23159190

RÉSUMÉ

The Buia Homo site, also known as Wadi Aalad, is an East African paleoanthropological site near the village of Buia that, due to its very rich yield from the late Early Pleistocene, has been intensively investigated since 1994. In this paper, which reports on the finds of the 2010-2011 excavations, we include new fossil evidence on previously identified taxa (i.e., reptiles), as well as the very first description of the small mammal, fish and bird remains discovered. In particular, this study documents the discovery of the first African fossil of the genus Burhinus (Aves, Charadriiformes) and of the first rodent from the site. This latter is identified as a thryonomyid rodent (cane rat), a relatively common taxon in African paleoanthropological faunal assemblages. On the whole, the new occurrences documented within the Buia vertebrate assemblage confirm the occurrence of taxa characterized by strong water dependence. The paleoenvironmental characteristics of the fauna are confirmed as fully compatible with the evidence obtained through sedimentology and facies analysis, documenting the sedimentary evolution of fluvio-deltaic and lacustrine systems.


Sujet(s)
Fossiles , Vertébrés/anatomie et histologie , Vertébrés/classification , Animaux , Os et tissu osseux/anatomie et histologie , Érythrée , Paléontologie , Dent/anatomie et histologie
6.
Am J Phys Anthropol ; 144(1): 119-30, 2011 Jan.
Article de Anglais | MEDLINE | ID: mdl-20718040

RÉSUMÉ

Cross-sectional geometrical (CSG) properties of an Iron Age Samnite group from the Alfedena necropolis (Abruzzo, Italy, 2600-2400 B.P.) are compared with a Ligurian Neolithic sample (6000-5500 B.P.). In the period under examination, Samnites were organized in a tribal confederation led by patrilinear aristocracies, indicating incipient social stratification. In comparison, Neolithic society lacked clear signs of social hierarchy. The subsistence of both groups was mainly based on pastoralism and agriculture, but changes in habitual behavior are expected due to the socio-economic transformations that characterized the Iron Age. The Samnites' warlike ideology suggests that unimanual weapon-use and training would have become frequent for males. The intensification of agriculture and the adoption of transhumant pastoralism, performed by a smaller subset of the population, likely led to a lower average level of logistic mobility. The strongly genderized ideology of the period suggests a strict sexual division of labor, with women primarily performing sedentary tasks. CSG properties based on periosteal contours were calculated for humeri, femora, and tibiae (N = 61). Results corroborated the expectations: Alfedena males show substantial humeral bilateral asymmetry, indicating prevalent use of one arm, likely due to weapon training. In both sexes lower limb results indicate reduced mobility with respect to the Neolithic group. Sexual dimorphism is significant in both humeral asymmetry and lower limb indicators of mobility. Although both groups could be broadly defined as agropastoral based on archeological and historical evidence, CSG analysis confirmed important differences in habitual behavior.


Sujet(s)
Archéologie , Fémur/anatomie et histologie , Humérus/anatomie et histologie , Tibia/anatomie et histologie , Adulte , Anthropologie culturelle , Anthropologie anatomique , Anthropométrie , Phénomènes biomécaniques , Diaphyse , Femelle , Histoire ancienne , Humains , Italie/ethnologie , Mode de vie , Mâle , Mouvement , Facteurs sexuels
7.
Clin Exp Immunol ; 161(3): 417-25, 2010 Sep.
Article de Anglais | MEDLINE | ID: mdl-20529089

RÉSUMÉ

We have identified previously a nuclear fluorescence reactivity (NFR) pattern on monkey oesophagus sections exposed to coeliac disease (CD) patients' sera positive for anti-endomysium antibodies (EMA). The aim of the present work was to characterize the NFR, study the time-course of NFR-positive results in relation to gluten withdrawal and evaluate the potential role of NFR in the follow-up of CD. Twenty untreated, 87 treated CD patients and 15 healthy controls were recruited and followed for 12 months. Their sera were incubated on monkey oesophagus sections to evaluate the presence of NFR by indirect immunofluorescence analysis. Duodenal mucosa samples from treated CD patients were challenged with gliadin peptides, and thus the occurrence of NFR in culture supernatants was assessed. The NFR immunoglobulins (Igs) reactivity with the nuclear extract of a human intestinal cell line was investigated. Serum NFR was present in all untreated CD patients, persisted up to 151 ± 37 days from gluten withdrawal and reappeared in treated CD patients under dietary transgressions. Serum NFR was also detected in two healthy controls. In culture supernatants of coeliac intestinal mucosa challenged with gliadin peptides, NFR appeared before EMA. The Igs responsible for NFR were identified as belonging to the IgA2 subclass. The NFR resulted differently from EMA and anti-nuclear antibodies, but reacted with two nuclear antigens of 65 and 49 kDa. A new autoantibody, named NFR related to CD, was described. Furthermore, NFR detection might become a valuable tool in monitoring adherence to a gluten-free diet and identifying slight dietary transgressions.


Sujet(s)
Autoanticorps/immunologie , Oesophage/immunologie , Fluorescence , Technique d'immunofluorescence indirecte/méthodes , Sérum/immunologie , Adolescent , Adulte , Animaux , Spécificité des anticorps/immunologie , Autoanticorps/sang , Autoanticorps/métabolisme , Cellules Caco-2 , Maladie coeliaque/sang , Maladie coeliaque/diagnostic , Maladie coeliaque/immunologie , Femelle , Études de suivi , Haplorhini , Humains , Immunoglobuline A/sang , Immunoglobuline A/immunologie , Intestin grêle/immunologie , Intestin grêle/métabolisme , Mâle , Adulte d'âge moyen , Techniques de culture d'organes , Jeune adulte
8.
Am J Phys Anthropol ; 133(3): 918-30, 2007 Jul.
Article de Anglais | MEDLINE | ID: mdl-17455286

RÉSUMÉ

Dental morphological traits were employed in this study as direct indicators of biological affinities among the populations that inhabited the Italian peninsula from the Upper Paleolithic-Mesolithic to Medieval times. Our analysis aims at contributing to the ongoing debate regarding the origin and spread of agriculture in the peninsula by contrasting the dental evidence of archaeological and modern molecular samples. It is not possible to generalize given the complex and dynamic nature of these populations. However, the results from the principal component analysis, maximum likelihood, mean measure of divergence, and multidimensional scaling do indicate a net separation of the Paleo-Mesolithic sample from the other groups that is not related to dental reduction. This suggests that the shift in dental morphology was the product of Neolithic populations migrating into the peninsula from other areas. Nonetheless, the Paleo-Mesolithic populations share several discriminative traits with the Neolithic group. The biological relevance of such evidence suggests that, to some minor extent, the spread of agriculture did not occur by total population replacement. Because of regional small sample sizes, this hypothesis cannot be tested on a micro-regional scale. It is, however, feasible to depict a scenario where processes of genetic mixture or replacement probably took place at different rates on a macro-regional level.


Sujet(s)
Agriculture/histoire , Dent/anatomie et histologie , Évolution biologique , Fossiles , Géographie , Histoire ancienne , Histoire médiévale , Humains , Italie
9.
Homo ; 58(2): 173-90, 2007.
Article de Anglais | MEDLINE | ID: mdl-17433326

RÉSUMÉ

The purpose of this study is to assess the state of health of 116 individuals whose remains were excavated from Byzantine period burials underneath the floor of an important Christian basilica from the site of Elaiussa Sebaste, Turkey. Elaiussa Sebaste was a Mediterranean coastal community, which began as a Roman town and continued as an early Christian Byzantine community until the end of the 7th century AD. The burials date from the middle of the 6th through the middle of the 7th centuries AD. We attempt to determine how high social status has influenced the type and frequency of skeletal lesions exhibited in this sample. All strata of this population show a number of chronic and acute health problems as indicated by skeletal lesions. Yet, only the frequency of degenerative joint disease (DJD) differs by sex, with males exhibiting a higher rate of DJD than females, p=0.09. There is no difference in the frequency of trauma among adult males and females. Non-specific skeletal lesions (cribra orbitalia, porotic hyperostosis, and periostitis) often associated with dietary and general stressors, but also with specific systemic diseases, are common in both sexes. The sub-adults primarily exhibit periostitis of the long bones and do not show skeletal lesions specific to malaria. It seems that high social ranking did not prevent serious ailments from affecting the health of individuals living in the Elaiussa Sebaste community.


Sujet(s)
Maladies osseuses/histoire , Fossiles , Archéologie , Funérailles , Christianisme , Régime alimentaire/histoire , Femelle , Fractures osseuses/histoire , État de santé , Histoire médiévale , Humains , Maladies articulaires/histoire , Mâle , Maladies parodontales/histoire , Périostite/histoire , Classe sociale , Turquie
10.
Am J Phys Anthropol ; 132(1): 48-58, 2007 Jan.
Article de Anglais | MEDLINE | ID: mdl-16883566

RÉSUMÉ

The Samnites are an Iron Age protohistoric people from the central region of Italy. The skeletal remains are from the Alfedena necropolis, 6th through 5th centuries B.C. Macchiarelli et al. (Antropologia Contemporanea 4 (1981) 239-243) were the first to report on cranial trauma for this population, presenting four cases with extreme injuries. We re-examined this well documented skeletal population for additional examples of trauma. Previously unexamined remains from Alfedena, excavated at the turn of the 20th century, are also included in our analysis (Mariani. 1901. "Aufidena", ricerche archeologiche e storiche del Sannio settentrionale. Roma: Acc Naz Dei Lincei). Of the 209 adult crania examined, 12.9% of them exhibited trauma. Analysis of location and frequency of cranial trauma revealed that cranial injuries to the head appear to originate from all directions. The high rate of cranial trauma underscores the violent circumstances experienced during the Iron Age protohistoric period of central Italy. Males are much more likely to exhibit cranial injury than females (P = 0.009). We conclude that the injuries received by Samnite male farmer-warriors occurred while defending pastoral-agricultural resources. Trauma rates are similar for some Iron Age populations and not for others. Behavior associated with violence during the Iron Age period can not be generalized for all populations found in Italy.


Sujet(s)
Culture (sociologie) , Ethnies/histoire , Paléopathologie , Crâne/traumatismes , Violence/histoire , Adulte , Femelle , Histoire ancienne , Humains , Italie , Mâle , Adulte d'âge moyen
11.
Oncogene ; 26(14): 2039-47, 2007 Mar 29.
Article de Anglais | MEDLINE | ID: mdl-17043656

RÉSUMÉ

Phosphatidylinositol 3-kinase (PI3K) is necessary for thyroid stimulating hormone (TSH)-induced cell cycle progression. To determine the molecular mechanism linking PI3K to TSH, we have identified a serine residue in p85alpha(PI3K) phosphorylated by protein kinase A (PKA) in vitro and in vivo. Expression of an alanine mutant (p85A) abolished cyclic AMP/TSH-induced cell cycle progression and was lethal in thyroid cells (FRTL-5). The aspartic version of the p85alpha(PI3K) (p85D) inhibited apoptosis following TSH withdrawal. The p85alpha(PI3K) wild type not the p85A bound PKA regulatory subunit RIIbeta in cells stimulated with cAMP or TSH. The binding of the aspartic version of p85alpha(PI3K) to RIIbeta was independent of cAMP or TSH stimulation. Similarly, binding of PI3K to p21Ras and activation of AKT, a downstream PI3K target, were severely impaired in cells expressing the p85A mutant. Finally, we found that the catalytic activity of PI3K was stimulated by TSH in cells expressing the wild-type p85alpha(PI3K) but not in cells expressing p85A. This latter mutant did not affect the epidermal growth factor-stimulated PI3K activity. We suggest that (1) TSH-cAMP-induced PKA phosphorylates p85alpha(PI3K) at serine 83, (2) phosphorylated p85alpha(PI3K) binds RIIbeta-PKA and targets PKAII to the membrane, and (3) PI3K activity and p21Ras binding to PI3K increase and activate PI3K downstream targets. This pathway is essential for the transmission of TSH-cAMP growth signals.


Sujet(s)
Cyclic AMP-Dependent Protein Kinases/métabolisme , AMP cyclique/métabolisme , Phosphatidylinositol 3-kinases/métabolisme , Thyréostimuline/métabolisme , Animaux , Catalyse , Cycle cellulaire/génétique , Prolifération cellulaire/effets des médicaments et des substances chimiques , Survie cellulaire , Cellules cultivées , Cyclic AMP-Dependent Protein Kinase RIIbeta Subunit , Souris , Mutation , Phosphatidylinositol 3-kinases/génétique , Phosphorylation , Sous-unités de protéines/génétique , Sous-unités de protéines/métabolisme , Protéines proto-oncogènes c-akt/métabolisme , Protéines proto-oncogènes p21(ras)/métabolisme , Rats , Sérine/génétique , Sérine/métabolisme , Thyréostimuline/pharmacologie
12.
Nature ; 440(7085): 755-6, 2006 Apr 06.
Article de Anglais | MEDLINE | ID: mdl-16598247

RÉSUMÉ

Prehistoric evidence for the drilling of human teeth in vivo has so far been limited to isolated cases from less than six millennia ago. Here we describe eleven drilled molar crowns from nine adults discovered in a Neolithic graveyard in Pakistan that dates from 7,500-9,000 years ago. These findings provide evidence for a long tradition of a type of proto-dentistry in an early farming culture.


Sujet(s)
Fossiles , Histoire de l'art dentaire , Dent , Culture (sociologie) , Émail dentaire , Femelle , Histoire ancienne , Humains , Mâle , Pakistan/ethnologie
13.
Reumatismo ; 56(1): 61-6, 2004.
Article de Anglais | MEDLINE | ID: mdl-15105912

RÉSUMÉ

OBJECTIVES: This study was conducted to test several hypotheses: 1. That rheumatoid arthritis and syphilis were New World diseases, only transmitted to the Old World subsequent to the passages of Christopher Columbus; 2. To indirectly test the hypothesis that lead poisoning was prevalent in Roman Italy by looking for its byproduct, gout; 3. To test the hypothesis of compromised sanitation in ancient Italy, on the basis of spondyloarthropathy frequency; and 4. To assess variation of trauma frequencies in ancient Italy, by examining frequency of focal periosteal reaction. METHODS: Skeletons from sites ranging from the Bronze Age to the Black Plague epidemic of 1485-1486 were macroscopically evaluated for focal periosteal reaction and for the cardinal signs of rheumatoid arthritis, treponemal disease, gout and spondyloarthropathy. RESULTS: Examination of 688 individuals revealed low frequency of focally distributed periosteal reaction (bumps) in sites dated from the 3400-700 years before present, sharply increasing in the 15th century. Diffuse periosteal reaction was present only as isolated occurrences secondary to hypertrophic osteoarthropathy and sabre shin reaction was notably absent. Erosive disease was uncommon and always oligoarticular in distribution. No marginal erosions were present, with the exception of an isolated metatarsal with classic overhanging edge sign of gout. Subchondral erosions, peripheral joint fusion and axial skeletal involvement identified spondyloarthropathy frequencies of 1-3%, independent of the antiquity of the site. CONCLUSIONS: Italy, prior to Columbus was like a virgin. Rheumatoid arthritis and treponemal disease (specifically syphilis) were not present, further supporting the contention that they are New World-derived diseases. Periosteal signs of minor trauma were rare prior to fifteenth century plague times. This suggests a potential role of domestic (as opposed to outside environment activities) in is development. The hypothesis for a role of lead poisoning in the demise of the Roman Empire is falsified by the rarity of gout. The frequency of spondyloarthropathy was significantly below that found in sanitarily challenged populations, suggesting high standards of hygiene in ancient Italy.


Sujet(s)
Polyarthrite rhumatoïde/histoire , Fossiles , Goutte/histoire , Amélioration du niveau sanitaire/histoire , Tréponématoses/histoire , Goutte/épidémiologie , Histoire ancienne , Histoire médiévale , Humains , Italie , Amélioration du niveau sanitaire/normes
14.
Am J Hum Genet ; 69(6): 1348-56, 2001 Dec.
Article de Anglais | MEDLINE | ID: mdl-11595973

RÉSUMÉ

Forty-seven mtDNAs collected in the Dominican Republic and belonging to the African-specific haplogroup L2 were studied by high-resolution RFLP and control-region sequence analyses. Four sets of diagnostic markers that subdivide L2 into four clades (L2a-L2d) were identified, and a survey of published African data sets appears to indicate that these clades encompass all L2 mtDNAs and harbor very different geographic/ethnic distributions. One mtDNA from each of the four clades was completely sequenced by means of a new sequencing protocol that minimizes time and expense. The phylogeny of the L2 complete sequences showed that the two mtDNAs from L2b and L2d seem disproportionately derived, compared with those from L2a and L2c. This result is not consistent with a simple model of neutral evolution with a uniform molecular clock. The pattern of nonsynonymous versus synonymous substitutions hints at a role for selection in the evolution of human mtDNA. Regardless of whether selection is shaping the evolution of modern human mtDNAs, the population screening of L2 mtDNAs for the mutations identified by our complete sequence study should allow the identification of marker motifs of younger age with more restricted geographic distributions, thus providing new clues about African prehistory and the origin and relationships of African ethnic groups.


Sujet(s)
ADN mitochondrial/génétique , Évolution moléculaire , Haplotypes/génétique , Phylogenèse , Séquence nucléotidique , République dominicaine , Variation génétique/génétique , Humains , Cinétique , Mutation/génétique , Réaction de polymérisation en chaîne , Polymorphisme de restriction
15.
Am J Hum Genet ; 69(4): 844-52, 2001 Oct.
Article de Anglais | MEDLINE | ID: mdl-11517423

RÉSUMÉ

Mitochondrial HVS-I sequences from 10,365 subjects belonging to 56 populations/geographical regions of western Eurasia and northern Africa were first surveyed for the presence of the T-->C transition at nucleotide position 16298, a mutation which has previously been shown to characterize haplogroup V mtDNAs. All mtDNAs with this mutation were then screened for a number of diagnostic RFLP sites, revealing two major subsets of mtDNAs. One is haplogroup V proper, and the other has been termed "pre*V," since it predates V phylogenetically. The rather uncommon pre*V tends to be scattered throughout Europe (and northwestern Africa), whereas V attains two peaks of frequency: one situated in southwestern Europe and one in the Saami of northern Scandinavia. Geographical distributions and ages support the scenario that pre*V originated in Europe before the Last Glacial Maximum (LGM), whereas the more recently derived haplogroup V arose in a southwestern European refugium soon after the LGM. The arrival of V in eastern/central Europe, however, occurred much later, possibly with (post-)Neolithic contacts. The distribution of haplogroup V mtDNAs in modern European populations would thus, at least in part, reflect the pattern of postglacial human recolonization from that refugium, affecting even the Saami. Overall, the present study shows that the dissection of mtDNA variation into small and well-defined evolutionary units is an essential step in the identification of spatial frequency patterns. Mass screening of a few markers identified using complete mtDNA sequences promises to be an efficient strategy for inferring features of human prehistory.


Sujet(s)
Climat froid , ADN mitochondrial/génétique , Émigration et immigration , Fréquence d'allèle/génétique , Glace , Phylogenèse , Afrique du Nord , Asie de l'Ouest , Europe , Marqueurs génétiques/génétique , Dépistage génétique , Haplotypes/génétique , Humains , Mutation/génétique , Polymorphisme de restriction , Taille de l'échantillon , Facteurs temps
16.
Ann Hum Genet ; 65(Pt 6): 549-63, 2001 Nov.
Article de Anglais | MEDLINE | ID: mdl-11851985

RÉSUMÉ

The mtDNA haplogroup L3e, which is identified by the restriction site +2349 MboI within the Afro-Eurasian superhaplogroup L3 (-3592 HpaI), is omnipresent in Africa but virtually absent in Eurasia (except for neighbouring areas with limited genetic exchange). L3e was hitherto poorly characterised in terms of HVS-I motifs, as the ancestral HVS-I type of L3e cannot be distinguished from the putative HVS-I ancestor of the entire L3 (differing from the CRS by a transition at np 16223). An MboI screening at np 2349 of a large number of Brazilian and Caribbean mtDNAs (encompassing numerous mtDNAs of African ancestry), now reveals that L3e is subdivided into four principal clades, each characterised by a single mutation in HVS-I, with additional support coming from HVS-II and partial RFLP analysis. The apparently oldest of these clades (transition at np 16327) occurs mainly in central Africa and was probably carried to southern Africa with the Bantu expansion(s). The most frequent clade (transition at np 16320) testifies to a pronounced expansion event in the mid-Holocene and seems to be prominent in many Bantu groups from all of Africa. In contrast, one clade (transition at np 16264) is essentially restricted to Atlantic western Africa (including Cabo Verde). We propose a tentative L3e phylogeny that is based on 197 HVS-I sequences. We conclude that haplogroup L3e originated in central or eastern Africa about 46,000 (+/-14,000) years ago, and was a hitchhiker of much later dispersal and local expansion events, with the rise of food production and iron smelting. Enforced migration of African slaves to the Americas translocated L3e mitochondria, the descendants of which in Brazil and the Caribbean still reflect their different regional African ancestries.


Sujet(s)
ADN mitochondrial/génétique , Haplotypes , Phylogenèse , Afrique/ethnologie , Brésil , Caraïbe , Bases de données génétiques , Émigration et immigration/histoire , Histoire ancienne , Temps
17.
Coll Antropol ; 25(2): 403-12, 2001 Dec.
Article de Anglais | MEDLINE | ID: mdl-11811270

RÉSUMÉ

The seasonality of 27,705 marriages celebrated in a four century span in the Province of Teramo (Abruzzo, Italy) was analyzed to identify the presence of a long-term pattern related to the prevailing subsistence activity and the main factors affecting it. The results show general agreement in all centuries with the agricultural patterns of other lowland or south-central Italian groups (Piedmont, Veneto, Liguria, Emilia Romagna, Tuscany, Latium, Compania, Apulia) and Mediterranean regions (Spain, France), although with some differences. Religious factors strongly affected the timing of marriage only during Lent. Of interest is the progressive increase through the centuries of marriages in the summer-autumn months, associated with a decrease in January and February. This suggests the passage from a summer migration system to a rural sedentary system with occasional seasonal work.


Sujet(s)
Agriculture , Écologie , Émigration et immigration , Mariage , Adolescent , Adulte , Anthropologie , Caractéristiques culturelles , Femelle , Humains , Italie/ethnologie , Mâle , Religion , Population rurale , Saisons
18.
Clin Infect Dis ; 31(4): 936-41, 2000 Oct.
Article de Anglais | MEDLINE | ID: mdl-11049773

RÉSUMÉ

Recognition of syphilis in Europe in the late 15th century and its prior absence suggest New World origin. Skeletal populations were examined from sites with documented Columbian contact in the Dominican Republic. Examination of 536 skeletal remains revealed periosteal reaction characteristic of treponemal disease in 6%-14% of the afflicted population. Findings were identical to that previously noted in confirmed syphilis-affected populations and distinctive from those associated with yaws and bejel: it was a low population frequency phenomenon, affecting an average of 1.7-2.6 bone groups, often asymmetric and sparing hands and feet, but associated with significant tibial remodeling. While findings diagnostic of syphilis have been reported in the New World, actual demonstration of syphilis in areas where Columbus actually had contact was missing, until now. The evidence is consistent with this site as the point of initial contact of syphilis and of its subsequent spread from the New World to the Old.


Sujet(s)
Syphilis/histoire , Os et tissu osseux/anatomopathologie , Diagnostic différentiel , République dominicaine , Europe , Fossiles , Histoire du 15ème siècle , Histoire du 16ème siècle , Histoire ancienne , Humains , Syphilis/diagnostic , Syphilis/transmission , Syphilis congénitale/diagnostic , Syphilis congénitale/histoire , Dent/anatomopathologie
19.
Atherosclerosis ; 152(1): 51-7, 2000 Sep.
Article de Anglais | MEDLINE | ID: mdl-10996339

RÉSUMÉ

A large body of evidences implicates transforming growth factor-beta (TGF-beta) in the pathogenesis of atherosclerosis. In this context, TGF-beta receptor dysfunction has been suggested to be relevant. We tested the effect of hypercholesterolemia, a well-known risk factor for atherosclerosis, on liver type II TGF-beta receptor (TbetaR-II) expression in atherosclerosis-susceptible C57BL/6 mouse strain fed atherogenic diet. In addition, the relationship between cholesterol and TbetaR-II expression was verified by cholesterol challenge on human hepatoma cell (HepG2) cultures. The susceptible C57BL/6 mice fed atherogenic diet exhibited significant mRNA and immunohistochemical TbetaR-II liver expression at 2, 5, 9 and 15 weeks as compared to animals fed a regular diet. The TbetaR-II profile on HepG2 resulted in a time-dependent increased expression when the cells were incubated with soluble free cholesterol, associated with an increased TGF-beta-dependent biological activity as detected by luciferase assay of reporter gene. These data provide evidence for a cholesterol-dependent TbetaR-II induction that may play a potentially relevant role in the development of hypercholesterolemia and atherogenesis.


Sujet(s)
Cholestérol/métabolisme , Régime athérogène , Hépatocytes/métabolisme , Récepteurs TGF-bêta/analyse , Régulation positive/physiologie , Analyse de variance , Animaux , Artériosclérose/métabolisme , Artériosclérose/anatomopathologie , Technique de Northern , Technique de Western , Cellules cultivées , Hépatocytes/effets des médicaments et des substances chimiques , Immunohistochimie , Souris , Souris de lignée C57BL , Modèles animaux , Probabilité , Valeurs de référence , Sensibilité et spécificité , Statistique non paramétrique
20.
Mol Endocrinol ; 14(4): 486-505, 2000 Apr.
Article de Anglais | MEDLINE | ID: mdl-10770487

RÉSUMÉ

Transforming growth factor (TGF)-beta1-decreased major histocompatibility complex (MHC) class I gene expression in thyrocytes is transcriptional; it involves trans factors and cis elements important for hormone- as well as iodide-regulated thyroid growth and function. Thus, in rat FRTL-5 thyrocytes, TGF-beta1 regulates two elements within -203 bp of the transcription start site of the MHC class I 5'-flanking region: Enhancer A, -180 to -170 bp, and a downstream regulatory element (DRE), -127 to -90 bp, that contains a cAMP response element (CRE)-like sequence. TGF-beta1 reduces the interaction of a NF-kappaB p50/fra-2 heterodimer (MOD-1) with Enhancer A while increasing its interaction with a NF-kappaB p50/p65 heterodimer. Both reduced MOD-1 and increased p50/p65 suppresses class I expression. Decreased MOD-1 and increased p50/p65 have been separately associated with the ability of autoregulatory (high) concentrations of iodide to suppress thyrocyte growth and function, as well as MHC class I expression. TGF-beta1 has two effects on the downstream regulatory element (DRE). It increases DRE binding of a ubiquitously expressed Y-box protein, termed TSEP-1 (TSHR suppressor element binding protein-1) in rat thyroid cells; TSEP-1 has been shown separately to be an important suppressor of the TSH receptor (TSHR) in addition to MHC class I and class II expression. It also decreases the binding of a thyroid-specific trans factor, thyroid transcription factor-1 (TTF-1), to the DRE, reflecting the ability of TGF-beta1 to decrease TTF-1 RNA levels. TGF-beta1-decreased TTF-1 expression accounts in part for TGF-beta1-decreased thyroid growth and function, since decreased TTF-1 has been shown to decrease thyroglobulin, thyroperoxidase, sodium iodide symporter, and TSHR gene expression, coincident with decreased MHC class I. Finally, we show that TGF-beta1 increases c-jun RNA levels and induces the formation of new complexes involving c-jun, fra-2, ATF-1, and c-fos, which react with Enhancer A and the DRE. TGF-beta1 effects on c-jun may be a pivotal fulcrum in the hitherto unrecognized coordinate regulation of Enhancer A and the DRE.


Sujet(s)
Peptides antimicrobiens cationiques , Protéines liant les séquences stimulatrices de type CCAAT , Régulation de l'expression des gènes/effets des médicaments et des substances chimiques , Gènes MHC de classe I , Glande thyroide/immunologie , Facteurs de transcription/pharmacologie , Facteur de croissance transformant bêta/pharmacologie , Animaux , Lignée cellulaire , AMP cyclique/pharmacologie , Protéine de liaison à l'élément de réponse à l'AMP cyclique/métabolisme , Protéines de liaison à l'ADN/métabolisme , Dimérisation , Éléments activateurs (génétique) , Humains , Facteur de transcription NF-kappa B/métabolisme , Facteur de transcription NF-kappa B/pharmacologie , Facteurs nucléaires-I , Protéines nucléaires/génétique , Protéines nucléaires/métabolisme , Peptides/métabolisme , Protéines proto-oncogènes c-jun/métabolisme , Rats , Séquences d'acides nucléiques régulatrices , Éléments de réponse , Facteur-1 de transcription de la thyroïde , Facteurs de transcription/génétique , Facteurs de transcription/métabolisme , Protéine-1 de liaison à la boîte Y
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