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Common Origin (common + origin)
Selected AbstractsPrenatal growth, postnatal growth and trait anxiety in late adulthood , the Helsinki Birth Cohort StudyACTA PSYCHIATRICA SCANDINAVICA, Issue 3 2010J. Lahti Lahti J, Räikkönen K, Pesonen A-K, Heinonen K, Kajantie E, Forsén T, Osmond C, Barker DJP, Eriksson JG. Prenatal growth, postnatal growth and trait anxiety in late adulthood , the Helsinki Birth Cohort Study. Objective:, Trait anxiety may predispose to anxiety disorders and cardiovascular events. We tested whether prenatal growth or postnatal growth from birth to 11 years of age and in adulthood predict trait anxiety in late adulthood. Method:, Women (n = 951) and men (n = 753) reported trait anxiety using the Spielberger Trait Anxiety Scale at an average age of 63.4 years and growth was estimated from records. Results:, Higher trait anxiety was predicted by smaller body size at birth, in infancy and in adulthood. Moreover, faster growth particularly from seven to 11 years of age and slower growth between 11 and 63 years predicted higher trait anxiety. Conclusion:, We found a pattern of pre- and postnatal growth that predisposed to higher trait anxiety in late adulthood. This pattern resembles that found to increase the risk of cardiovascular events and, thus, points to a shared common origin in a suboptimal prenatal and childhood developmental milieu. [source] On the origin of the chordate central nervous system: expression of onecut in the sea urchin embryoEVOLUTION AND DEVELOPMENT, Issue 4 2004Albert J. Poustka Summary We identified a transcription factor of the onecut class in the sea urchin Strongylocentrotus purpuratus that represents an ortholog of the mammalian gene HNF6, the founding member of the onecut class of proteins. The isolated sea urchin gene, named SpOnecut, encodes a protein of 483 amino acids with one cut domain and a homeodomain. Phylogenetic analysis clearly places the sea urchin gene into this family, most closely related to the ascidian onecut gene HNF-6. Nevertheless, phylogenetic analysis reveals a difficult phylogeny indicating that certain members of the family evolve more rapidly than others and also that the cut domain and homeodomain evolve at a different pace. In fly, worm, ascidian, and teleost fish, the onecut genes isolated so far are exclusively expressed in cells of the central nervous system (CNS), whereas in mammals the two copies of the gene have acquired additional functions in liver and pancreas development. In the sea urchin embryo, expression is first detected in the emerging ciliary band at the late blastula stage. During the gastrula stage, expression is limited to the ciliary band. In the early pluteus stage, SpOnecut is expressed at the apical organ and the elongating arms but continues most prominently in the ciliary band. This is the first gene known that exclusively marks the ciliary band and therein the apical organ in a pluteus larva, whereas chordate orthologs execute essential functions in dorsal CNS development. The significance of this finding for the hypothesis that the ciliary bands and apical organs of the hypothetical "dipleurula"-like chordate ancestor and the chordate/vertebrate CNS are of common origin is discussed. [source] Cre-mediated recombination in pituitary somatotropesGENESIS: THE JOURNAL OF GENETICS AND DEVELOPMENT, Issue 1 2009Igor O. Nasonkin Abstract We report a transgenic line with highly penetrant cre recombinase activity in the somatotrope cells of the anterior pituitary gland. Expression of the cre transgene is under the control of the locus control region of the human growth hormone gene cluster and the rat growth hormone promoter. Cre recombinase activity was assessed with two different lacZ reporter genes that require excision of a floxed stop sequence for expression: a chick ,-actin promoter with the CMV enhancer transgene and a ROSA26 knock-in. Cre activity is detectable in the developing pituitary after initiation of Gh transcription and persists through adulthood with high penetrance in Gh expressing cells and lower penetrance in lactotropes, a cell type that shares a common origin with somatotropes. This Gh-cre transgenic line is suitable for efficient, cell-specific deletion of floxed regions of genomic DNA in differentiated somatotropes and a subset of lactotrope cells of the anterior pituitary gland. genesis 47:55,60, 2009. © 2008 Wiley-Liss, Inc. [source] Iterative resolution estimation in least-squares Kirchhoff migrationGEOPHYSICAL PROSPECTING, Issue 6 2002Sergey Fomel ABSTRACT We apply iterative resolution estimation to least-squares Kirchhoff migration. Reviewing the theory of iterative optimization uncovers the common origin of different optimization methods. This allows us to reformulate the pseudo-inverse, model resolution and data resolution operators in terms of effective iterative estimates. When applied to Kirchhoff migration, plots of the diagonal of the model resolution matrix reveal low illumination areas on seismic images and provide information about image uncertainties. Synthetic and real data examples illustrate the proposed technique and confirm the theoretical expectations. [source] The Merchant Adventurers of England: their origins and the Mercers' Company of LondonHISTORICAL RESEARCH, Issue 187 2002Anne F. Sutton The history of the adventurers, or overseas merchants, trading to the Low Countries is taken back to their earliest privileges, those from Brabant 1296,1315, to the establishment of their fraternity of St. Thomas c.1300, and to their common origin with the staplers. This discounts the theories that they owed their beginnings to the Mercers' Company of London. The rise of the London mercers to an increasingly dominant position among the Adventurers to the Low Countries is traced from c.1400, and their records, the frequently misleading acts of court, are re-examined. The theory that the Company of the Merchant Adventurers of England was created at the end of the fifteenth century is similarly discounted. [source] The Fate of Jewish Historiography after the Bible: A New InterpretationHISTORY AND THEORY, Issue 2 2004Amram Tropper What caused the eventual decline in later Jewish history of the vibrant historiographical tradition of the biblical period? In contrast to the plethora of historical writings composed during the biblical period, the rabbis of the early common era apparently were not interested in writing history, and when they did relate to historical events they often introduced mythical and unrealistic elements into their writings. Scholars have offered various explanations for this phenomenon; a central goal of this article is to locate these explanations within both the immediate historical setting of Roman Palestine and the overarching cultural atmosphere of the Greco-Roman Near East. In particular, I suggest that the largely ahistorical approach of the rabbis functioned as a local Jewish counterpart to the widespread classicizing tendencies of a contemporary Greek intellectual movement, the Second Sophistic. In both cases, eastern communities, whose political aspirations were stifled under Roman rule, sought to express their cognitive and spiritual identities by focusing on a glorious and idealized past rather than on contemporary history. Interestingly, the apparent lack of rabbinic interest in historiography is not limited to the early rabbinic period. Throughout the Middle Ages and into the Renaissance, Jews essentially did not write their political, diplomatic, or military history. Instead, Jews composed "traditional historiography" which included various types of literary genres among which the rabbinic "chain of transmission" was the most important. The chain of transmission reconstructs (or fabricates) the links that connect later rabbinic sages with their predecessors. Robert Bonfil has noted the similarity between this rabbinic project and contemporary church histories. Adding a diachronic dimension to Bonfil's comparison, I suggest that rabbinic chains of transmission and church histories are not similar though entirely independent phenomena, but rather their shared project actually derives from a common origin, the Hellenistic succession list. The succession list literary genre, which sketches the history of an intellectual discipline, apparently thrived during the Second Sophistic and diffused then into both rabbinic Judaism and early Christianity. Thus, even though historiography was not terribly important to the early rabbis or to most Second Sophistic intellectuals, the succession list schematic, or the history of an intellectual discipline, was evaluated differently. Rabbis and early Christians absorbed the succession list from Second Sophistic culture and then continued to employ this historiographical genre for many centuries to come. [source] The ,oestrogen hypothesis', where do we stand now?,INTERNATIONAL JOURNAL OF ANDROLOGY, Issue 1 2003Richard M. Sharpe Summary The original ,oestrogen hypothesis' postulated that the apparent increase in human male reproductive developmental disorders (testis cancer, cryptorchidism, hypospadias, low sperm counts) might have occurred because of increased oestrogen exposure of the human foetus/neonate; five potential routes of exposure were considered. This review revisits this hypothesis in the light of the data to have emerged since 1993. It addresses whether there is a secular increasing trend in the listed disorders and highlights the limitations of available data and how these are being addressed. It considers whether new data has emerged to support the suggestion that increased oestrogen exposure could cause these abnormalities and reviews new data on potential routes via which such increased exposure could have occurred. Secular trends: The disorders listed above are now considered to represent a syndrome of disorders (testicular dysgenesis syndrome, TDS) with a common origin in foetal life. Testicular cancer has increased in incidence in Caucasian men worldwide and lifetime risk is 0.3,0.8%. Secular trends in cryptorchidism are unclear but it is by far the commonest (2,4% at birth) congenital abnormality in either sex. Secular trends for hypospadias are not robust, although most studies suggest a progressive increase; registry data probably under-estimates incidence, but based on this data hypospadias is the second most common (0.3,0.7% at birth) congenital malformation. Retrospective analyses of sperm count data show a global downward trend but this is inconclusive , prospective studies using standardized methodology show significant differences between countries and very low sperm counts in the youngest cohort of men. For all disorders, other then testis cancer, standardized prospective studies are the best way forward and are in progress across Europe. Oestrogen effects: Evidence that foetal exposure to oestrogens can induce the above disorders has strengthened. New pathways via which such changes could be induced have been identified, including suppression of testosterone production by the foetal testis, suppression of androgen receptor expression and suppression of insulin-like factor-3 (InsL3) production by foetal Leydig cells. Other evidence suggests that the balance between androgen and oestrogen action may be important in induction of reproductive tract abnormalities. Oestrogen exposure: Although many new environmental oestrogens have been identified, their uniformly weak oestrogenicity excludes the possibility that they could induce the above disorders. However, emerging data implicates various environmental chemicals in being able to alter endogenous levels of androgens (certain phthalates) and oestrogens (polychlorinated biphenyls, polyhalogenated hydrocarbons), and the former have been shown to induce a similar collection of disorders to TDS. Other mechanisms via which increased fetal exposure to pregnancy oestrogens might occur (increasing trend in obesity, dietary changes) are also discussed. [source] Roles of JNK-1 and p38 in selective induction of apoptosis by capsaicin in ras -transformed human breast epithelial cellsINTERNATIONAL JOURNAL OF CANCER, Issue 4 2003Hye-Jung Kang Abstract Efforts have been made to develop a chemoprevention strategy that selectively triggers apoptosis in malignant cancer cells. Previous studies showed that capsaicin, the major pungent ingredient of red pepper, had differential effect between normal and transformed cells. As an approach to unveil the molecular mechanism by which capsaicin selectively induces apoptosis in transformed cells, we investigated the effect of capsaicin in nontransformed and ras -transformed cells of a common origin: parental (MCF10A) and H- ras -transformed (H- ras MCF10A) human breast epithelial cells. Here, we show that capsaicin selectively induces apoptosis in H- ras -transformed cells but not in their normal cell counterparts. The capsaicin-induced apoptosis, which is dependent on ras transformation, involves the activity of DEVDase (caspase-3 like). In H - ras MCF10A cells, capsaicin treatment markedly activated c-Jun N-terminal protein kinase (JNK)-1 and p38 matigen-activated protein kinase (MAPK) while it deactivated extracellular signal-regulated protein kinases (ERKs). The use of kinase inhibitors and overexpression of dominant-negative forms of MAPKs demonstrated a role of JNK-1 and p38, but not that of ERKs, in apoptosis induced by capsaicin in H- ras -transformed MCF10A cells. Based on the present study, we propose that capsaicin selectively induces apoptosis through modulation of ras -downstream signaling molecules in ras -activated MCF10A cells. Taken in conjunction with the fact that uncontrolled ras activation is probably the most common genetic defect in human cancer cells, our finding may be critical to the chemopreventive potential of capsaicin and for developing a strategy to induce tumor cell-specific apoptosis. © 2002 Wiley-Liss, Inc. [source] Co-inheritance of haemoglobin A2, and beta-thalassaemia in cisINTERNATIONAL JOURNAL OF LABORATORY HEMATOLOGY, Issue 4 2008P. VERMEERSCH Summary HbA2, is a haematologically silent , chain variant that elutes in the S-region on high performance liquid chromatography. The major clinical significance of HbA2, is that failure to detect it might lead to failure to recognize , -thalassaemia minor. Co-inheritance of HbA2, and , -thalassaemia in cis has been described only once in a family from Suriname. We describe a new case of co-inheritance in cis of HbA2, and , -thalassaemia in a family from Ghanaian origin with a HbA2, of more than 3%. Molecular investigation revealed the same mutations as in the family from Suriname, suggesting a common origin of both families. [source] Morphological and biochemical analyses of otoliths of the ice-fish Chionodraco hamatus confirm a common origin with red-blooded speciesJOURNAL OF ANATOMY, Issue 1 2009Chiara Maria Motta Abstract The morphology and composition of the three otoliths of the Antarctic ice-fish Chionodraco hamatus were studied by scanning electron microscopy and X-ray diffraction. The composition of the sagitta, lapillus and asteriscus protein matrices was also analysed by sodium dodecyl sulphate-polyacrylamide gel electrophoresis, western blots and confocal laser scanning microscopy to reveal the presence of and to localize the calcium-binding proteins calmodulin, calbindin and S-100. Morphological results indicated that the otoliths in this ice-fish were similar to those of Trematomus bernacchii, a red-blooded Antarctic species [B. Avallone et al. (2003) J. Submicrosc. Cytol. Pathol. 35, 69,76], but rather different from those of other teleosts. These two Antarctic species possessed a completely vateritic asteriscus, whereas their sagitta and lapillus were made mostly of aragonite. Parallel analysis of protein patterns in C. hamatus and T. bernacchii revealed that the sagitta significantly differed from the lapillus and asteriscus in both species. The sagitta did not contain the S-100 protein and showed calmodulin and calbindin located in discontinuous or incremental zones, respectively. These results demonstrate that the otoliths of C. hamatus and T. bernacchii share more resemblances than differences and support the idea of a common origin of these species. [source] Fluctuating asymmetry and developmental instability in evolutionary biology: past, present and futureJOURNAL OF EVOLUTIONARY BIOLOGY, Issue 6 2006S. V. DONGEN Abstract The role of developmental instability (DI), as measured by fluctuating asymmetry (FA), in evolutionary biology has been the focus of a wealth of research for more than half a century. In spite of this long period and many published papers, our current state of knowledge reviewed here only allows us to conclude that patterns are heterogeneous and that very little is known about the underlying causes of this heterogeneity. In addition, the statistical properties of FA as a measure of DI are only poorly grasped because of a general lack of understanding of the underlying mechanisms that drive DI. If we want to avoid that this area of research becomes abandoned, more efforts should be made to understand the observed heterogeneity, and attempts should be made to develop a unifying statistical protocol. More specifically, and perhaps most importantly, it is argued here that more attention should be paid to the usefulness of FA as a measure of DI since many factors might blur this relationship. Furthermore, the genetic architecture, associations with fitness and the importance of compensatory growth should be investigated under a variety of stress situations. In addition, more focus should be directed to the underlying mechanisms of DI as well as how these processes map to the observable phenotype. These insights could yield more efficient statistical models and a unified approach to the analysis of patterns in FA and DI. The study of both DI and canalization is indispensable to obtain better insights in their possible common origin, especially because both have been suggested to play a role in both micro- and macro-evolutionary processes. [source] Phylogenetic and molecular analysis of HTLV-1 isolates from a medium sized town in Northern of Brazil: Tracing a common origin of the virus from the most endemic city in the country,JOURNAL OF MEDICAL VIROLOGY, Issue 11 2008Themístocles Magalhães Abstract Salvador-Bahia has the highest prevalence of HTLV-1 infection in Brazil; about 2% of the population is infected. In this city, the prevalence of HTLV in pregnant women is 1%. There is no data of the HTLV-1 prevalence in others cities of the Bahia's Recôncavo, where the population has similar social and demography characteristics to those from Salvador. Our aim was to evaluate the seroprevalence of HTLV in pregnant women in Cruz das Almas-Bahia, a medium-sized city from the Bahia's Recôncavo. All individuals were tested for HTLV (ELISA) and the positive samples were confirmed by Western Blot. Phylogenetic analyses of the total LTR region were performed in all positive samples. We tested 408 samples (45.4% of the estimate pregnant women population) between June 1st and October 31, 2005. The prevalence of HTLV-1 infection was 0.98%. In addition, all isolated virus were grouped in the subtype HTLV-1a, in the Latin American group. Our results suggest that the introduction of HTLV-1 occurred after the slave trade into Salvador. In addition, HTLV-1-infection should be screened during the pregnancy in women originating from HTLV-1 endemic areas. J. Med. Virol. 80:2040,2045, 2008. © 2008 Wiley-Liss, Inc. [source] Early steps in neural developmentJOURNAL OF MORPHOLOGY, Issue 7 2006Marc Callebaut Abstract We studied early neurulation events in vitro by transplanting quail Hensen's node, central prenodal regions (before the nodus as such develops), or upper layer parts of it on the not yet definitively committed upper layer of chicken anti-sickle regions (of unincubated blastoderms), eventually associated with central blastoderm fragments. We could demonstrate by this quail-chicken chimera technique that after the appearance of a pronounced thickening of the chicken upper layer by the early inductive effect of neighboring endophyll, a floor plate forms by insertion of Hensen's node-derived quail cells into the median part of the groove. This favors, at an early stage, the floor plate "allocation" model that postulates a common origin for notochord and median floor plate cells from the vertebrate's secondary major organizer (Hensen's node in this case). A comparison is made with results obtained after transplantation of similar Hensen's nodes in isolated chicken endophyll walls or with previously obtained results after the use of the grafting procedure in the endophyll walls of whole chicken blastoderms. J. Morphol. © 2006 Wiley-Liss, Inc. [source] COMMON EVOLUTIONARY ORIGIN OF STARCH BIOSYNTHETIC ENZYMES IN GREEN AND RED ALGAE,JOURNAL OF PHYCOLOGY, Issue 6 2005Nicola J. Patron Plastidic starch synthesis in green algae and plants occurs via ADP-glucose in likeness to prokaryotes from which plastids have evolved. In contrast, floridean starch synthesis in red algae proceeds via uridine diphosphate-glucose in semblance to eukaryotic glycogen synthesis and occurs in the cytosol rather than the plastid. Given the monophyletic origin of all plastids, we investigated the origin of the enzymes of the plastid and cytosolic starch synthetic pathways to determine whether their location reflects their origin,either from the cyanobacterial endosymbiont or from the eukaryotic host. We report that, despite the compartmentalization of starch synthesis differing in green and red lineages, all but one of the enzymes of the synthetic pathways shares a common origin. Overall, the pathway of starch synthesis in both lineages represents a chimera of the host and endosymbiont glycogen synthesis pathways. Moreover, host-derived proteins function in the plastid in green algae, whereas endosymbiont-derived proteins function in the cytosol in red algae. This complexity demonstrates the impacts of integrating pathways of host with those of both primary and secondary endosymbionts during plastid evolution. [source] Descent with Modification: Bioanthropological Identities in 2009AMERICAN ANTHROPOLOGIST, Issue 2 2010Julienne Rutherford ABSTRACT, In the year of Darwin, what were the emerging themes and events that united disparate manifestations of bioanthropological identities? In this review, I draw from conference proceedings, the literature, and electronic social networking to assess six major developments in 2009: the bioanthropological legacy of Darwin on the 200th anniversary of his birth; the efforts of primatologists from a multitude of backgrounds to grapple with the construction of a unified ethics; the remediation of philosophical tensions between field and captive primatology; the coalescence of an explicitly comparative evolutionary anthropology; the role of conference attendance and collaborations in forging disciplinary identity; and the provocative implications of the Ardipithecus ramidus story. The field of biological anthropology continues to evolve and diversify, obscuring a common identity, but as in other organic fractal systems, a common origin as anthropologists leads to descent with modification. [source] Are cranial germ cell tumours really tumours of germ cells?NEUROPATHOLOGY & APPLIED NEUROBIOLOGY, Issue 6 2006P. J. Scotting Germ cell tumours of the brain and those that occur in the gonads are believed to share a common origin from germ cell progenitors. This ,germ cell theory' rests upon similar histopathology between these tumours in different locations and the belief that endogenous somatic cells of the brain could not give rise to the range of cell types seen in germ cell tumours. An alternative ,embryonic cell theory' has been proposed for some classes of cranial germ cell tumours, but this still relies on the misplacement of cells in the brain (in this case the earliest embryonic stem cells) during early embryonic development. Recent evidence has demonstrated that neural stem cells of the brain can also give rise to many of the cell types seen in germ cell tumours. These data suggest that endogenous progenitor cells of the brain are a plausible alternative origin for these tumours. This idea is of central importance for studies aiming to elucidate the mechanisms of tumour development. The application of modern molecular analyses to reveal how tumour cells have altered with respect to their cell of origin relies on the certain identification of the cell from which the particular tumour arose. If the identity of this cell is mistaken, then studies to elucidate the mechanisms by which the progenitor cell has been subverted from its normal behaviour will not yield useful information. In addition, it will prove impossible to generate an appropriate animal model in which to study the underlying causes of those tumours. This article makes the case that current assumptions of the origins of cranial germ cell tumours are unreliable. It reviews the evidence in favour of the ,germ cell theory' and argues in favour of a ,brain cell theory' in which endogenous neural progenitor cells of the brain are the likely origin for these tumours. Thus, the case is made that cranial germ cell tumours, like other brain tumours, arise by the transformation of progenitor cells normally resident in the brain. [source] Expression of CD34 as a novel marker for glioneuronal lesions associated with chronic intractable epilepsyNEUROPATHOLOGY & APPLIED NEUROBIOLOGY, Issue 5 2006P. Deb The spectrum of glioneuronal lesions underlying intractable epilepsies includes malformative pathologies like focal cortical dysplasia (FCD); and neoplastic lesions like gangliogliomas (GG) and dysembryoplastic neuroepithelial tumours (DNT). These may occur either singly or as dual lesions, having simultaneous presence of both elements. Currently, the relationship between the malformative and neoplastic glioneuronal lesions is poorly understood. Recently, CD34, a stem cell marker transiently expressed during early neurulation, has been identified in these tumours. This study was undertaken to (i) evaluate the role of CD34 as a diagnostic marker for glioneuronal lesions of epilepsy, namely, GG, DNT and FCD, and (ii) attempt to define the relationship among these lesions, using CD34 as a marker. Tissues resected from 47 patients with intractable epilepsy due to glioneuronal lesions (GG, FCD, DNT) were studied. These were evaluated for CD34 expression, using immunohistochemistry. Dysplastic or atypically differentiated neural precursors which could not be identified on routine haematoxylin and eosin (H&E) staining were highlighted by CD34 immunostaining. The pattern of immunostaining was diffuse in GGs, unlike FCDs, wherein cells were present singly or in small clusters. However, cases of DNT and control tissue were largely CD34-immunonegative. Based on these findings, we propose a possible common origin of GG and FCD, from a bipotent precursor that undergoes abnormal glioneuronal development, while DNTs possibly have a different origin. The CD34-immunoreactive cells represent dysplastic or undifferentiated neural precursors, which may signify a valuable marker for the diagnostic evaluation of neoplastic and/or malformative pathologies in patients with intractable epilepsy. [source] Genetic structure and affinities of the corsican population (France): Classical genetic markers analysisAMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 2 2003G. Vona The frequencies of 19 classical genetic markers for a total of 54 alleles were studied in a sample of 1,164 individuals born and residing in five different regions of Corsica. The results, which are also discussed in the context of the Mediterranean populations, show the existence within Corsica of a certain genetic differentiation between north and south which follows the linguistic subdivision differentiation. Compared to the other Mediterranean populations, Corsica also appears to be greatly differentiated from the populations of regions such as France and Tuscany, regions which have had great political and cultural influence. The Mediterranean population most comparable to Corsica is Sardinia. Despite their common origin, however, they do not prove to be absolutely identical. The genetic characteristics of Corsica and their relationship with the Mediterranean populations are interpreted in terms of demographic and matrimonial structure, isolation, and genetic drift. Am. J. Hum. Biol. 15:151,163, 2003. © 2003 Wiley-Liss, Inc. [source] New insights into the active site structure and catalytic mechanism of tyrosinase and its related proteinsPIGMENT CELL & MELANOMA RESEARCH, Issue 6 2009Concepcion Olivares Summary Tyrosinases are widely distributed in nature. They are copper-containing oxidases belonging to the type 3 copper protein family, together with catechol oxidases and haemocyanins. Tyrosinases are essential enzymes in melanin biosynthesis and therefore responsible for pigmentation of skin and hair in mammals, where two more enzymes, the tyrosinase-related proteins (Tyrps), participate in the pathway. The structure and catalytic mechanism of mammalian tyrosinases have been extensively studied but they are not completely understood because of the lack of information on the tertiary structure. The availability of crystallographic data of one plant catechol oxidase and one bacterial tyrosinase has improved the model of the three-dimensional structure of the active site of the enzyme. Furthermore, sequence comparison of tyrosinase and the Tyrps reveals that the three orthologue proteins share many key structural features, because of their common origin from an ancestral gene, although the specific residues responsible for their different catalytic capabilities have not been identified yet. This review summarizes our current knowledge of tyrosinase and Tyrps structure and function and describes the catalytic mechanism of tyrosinase and Dct/Tyrp2, which are better characterized. [source] Characterization of Passionfruit severe leaf distortion virus, a novel begomovirus infecting passionfruit in Brazil, reveals a close relationship with tomato-infecting begomovirusesPLANT PATHOLOGY, Issue 2 2010S. S. Ferreira Molecular and biological characterization of the begomovirus isolate BR:LNS2:Pas:01, obtained from yellow passionfruit plants in Livramento de Nossa Senhora, Bahia state, Brazil, was carried out. Sequence analysis demonstrated that the BR:LNS2:Pas:01 DNA-A had highest nucleotide sequence identity with Tomato chlorotic mottle virus (77%) and had five ORFs corresponding to the genes cp, rep, trap, ren and ac4. The DNA-B had highest nucleotide sequence identity with Tomato yellow spot virus (74%) and two ORFs corresponding to the genes mp and nsp. These identity values indicate that this isolate represents a new begomovirus species, for which the name Passionfruit severe leaf distortion virus (PSLDV), is proposed. Phylogenetic analysis clustered the PSLDV DNA-A and -B in a monophyletic branch with Brazilian tomato-infecting begomoviruses. The isolate's host range was restricted to species from the Passifloraceae and Solanaceae. PSLDV-[BR:LNS2:Pas:01] was capable of forming pseudorecombinants with tomato-infecting begomoviruses, reinforcing its close relationship with these viruses and suggesting a possible common origin. However, the virus was not capable of infecting tomato. [source] Protein stability indicates divergent evolution of PD-(D/E)XK type II restriction endonucleasesPROTEIN SCIENCE, Issue 8 2002Monika Fuxreiter SC, stabilization center; PDB, Protein Data Bank Abstract Type II restriction endonucleases recognize 4,8 base-pair-long DNA sequences and catalyze their cleavage with remarkable specificity. Crystal structures of the PD-(DE)XK superfamily revealed a common ,/, core motif and similar active site. In contrast, these enzymes show little sequence similarity and use different strategies to interact with their substrate DNA. The intriguing question is whether this enzyme family could have evolved from a common origin. In our present work, protein structure stability elements were analyzed and compared in three parts of PD-(DE)XK type II restriction endonucleases: (1) core motif, (2) active-site residues, and (3) residues playing role in DNA recognition. High correlation was found between the active-site residues and those stabilization factors that contribute to preventing structural decay. DNA recognition sites were also observed to participate in stabilization centers. It indicates that recognition motifs and active sites in PD-(DE)XK type II restriction endonucleases should have been evolutionary more conserved than other parts of the structure. Based on this observation it is proposed that PD-(DE)XK type II restriction endonucleases have developed from a common ancestor with divergent evolution. [source] A genetic historical sketch of European Gypsies: The perspective from autosomal markersAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 4 2010Alfredo Gusmão Abstract In this study, 123 unrelated Portuguese Gypsies were analyzed for 15 highly polymorphic autosomal short tandem repeats (STRs). Average gene diversity across the 15 markers was 76.7%, which is lower than that observed in the non-Gypsy Portuguese population. Subsets of STRs were used to perform comparisons with other Gypsy and corresponding host populations. Interestingly, diversity reduction in Gypsy groups compared to their non-Gypsy surrounding populations apparently varied according to an East-West gradient, which parallels their dispersion in Europe as well as a decrease in complexity of their internal structure. Analysis of genetic distances revealed that the average level of genetic differentiation between Gypsy groups was much larger than that observed between the corresponding non-Gypsy populations. The high rate of heterogeneity among Gypsies can be explained by strong genetic drift and limited intergroup gene flow. However, when genetic relationships were addressed through principal component analysis, all Gypsy populations clustered together and was clearly distinguished from other populations, a pattern that suggests their common origin. Concerning the putative ancestral genetic component, admixture analysis did not reveal strong Indian ancestry in the current Gypsy gene pools, in contrast to the high admixture estimates for either Europeans or Western Asians. Am J Phys Anthropol 2010. © 2009 Wiley-Liss, Inc. [source] Phylogeographic analysis of paternal lineages in NE Portuguese Jewish communitiesAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 3 2010Inês Nogueiro Abstract The establishment of Jewish communities in the territory of contemporary Portugal is archaeologically documented since the 3rd century CE, but their settlement in Trás-os-Montes (NE Portugal) has not been proved before the 12th century. The Decree of Expulsion followed by the establishment of the Inquisition, both around the beginning of the 16th century, accounted for a significant exodus, as well as the establishment of crypto-Jewish communities. Previous Y chromosome studies have shown that different Jewish communities share a common origin in the Near East, although they can be quite heterogeneous as a consequence of genetic drift and different levels of admixture with their respective host populations. To characterize the genetic composition of the Portuguese Jewish communities from Trás-os-Montes, we have examined 57 unrelated Jewish males, with a high-resolution Y-chromosome typing strategy, comprising 16 STRs and 23 SNPs. A high lineage diversity was found, at both haplotype and haplogroup levels (98.74 and 82.83%, respectively), demonstrating the absence of either strong drift or founder effects. A deeper and more detailed investigation is required to clarify how these communities avoided the expected inbreeding caused by over four centuries of religious repression. Concerning haplogroup lineages, we detected some admixture with the Western European non-Jewish populations (R1b1b2-M269, ,28%), along with a strong ancestral component reflecting their origin in the Middle East [J1(xJ1a-M267), ,12%; J2-M172, ,25%; T-M70, ,16%] and in consequence Trás-os-Montes Jews were found to be more closely related with other Jewish groups, rather than with the Portuguese non-Jewish population. Am J Phys Anthropol 2010. © 2009 Wiley-Liss, Inc. [source] Evolutionary significance of cranial variation in Asian Homo erectusAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 4 2002Susan C. Antón Abstract Homo erectus inhabited a wide geographic area of Asia, ranging from 40° north latitude in China to 8° south latitude in island Southeast Asia. Yet variation within Asian H. erectus and its relation to ecological and temporal parameters have been little studied. I synthesize the revised radiometric chronologies for hominid sites in Asia and their relation to new oxygen isotope curves (proxies for climatic fluctuations and landbridge connections). These data suggest substantial opportunities in the later Pleistocene for both regional isolation and gene flow between hominids in mainland and Southeast Asia. They also suggest that the most northerly located Chinese sites (Zhoukoudian and Nanjing) may have been occupied during sequential, interglacial periods. Probably reflecting these periods of isolation, nonmetric features and principal components analysis (PCA) of calvarial shape suggest regional differentiation between northern Asian and Southeast Asian H. erectus. The most recent Southeast Asian fossils (e.g., Ngandong) conform to the Southeast Asian pattern. Except perhaps in brain size, there is no evidence that the temporally intermediate Chinese fossils are intermediate in morphology between older and younger Indonesian fossils. In fact, northern Chinese calvaria are easier to exclude from the larger Asian H. erectus hypodigm than are the Ngandong fossils. The Chinese specimens differ from the others based on their narrower occipitals and frontals for their cranial size. The Chinese sample from Zhoukoudian alone is thus not a good proxy for the morphology and variation seen within Asian H. erectus. Both the Chinese and late Indonesian samples exhibit less variation than does the early Indonesian sample; this along with their shared morphological bauplan suggests a common origin and no more than subspecific differentiation. This shared morphology, despite regional differences, was likely maintained by the increasing intensity of multiple glaciations (and longer-lasting land bridge connections) between mainland and island Southeast Asia during the last million years. Am J Phys Anthropol 118:301,323, 2002. © 2002 Wiley-Liss, Inc. [source] Genetics of atrioventricular conduction disease in humansTHE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 2 2004D. Woodrow Benson Abstract Atrioventricular (AV) conduction disease (block) describes impairment of the electrical continuity between the atria and ventricles. Classification of AV block has utilized biophysical characteristics, usually the extent (first, second, or third degree) and site of block (above or below His bundle recording site). The genetic significance of this classification is unknown. In young patients, AV block may result from injury or be the major cardiac manifestation of neuromuscular disease. However, in some cases, AV block has unknown or idiopathic cause. In such cases, familial clustering has been noted and published pedigrees show autosomal dominant inheritance; associated heart disease is common (e.g., congenital heart malformation, cardiomyopathy). The latter finding is not surprising given the common origin of working myocytes and specialized conduction system elements. Using genetic models incorporating reduced penetrance (disease absence in some individuals with disease gene), variable expressivity (individuals with disease gene have different phenotypes), and genetic heterogeneity (similar phenotypes, different genetic cause), molecular genetic causes of AV block are being identified. Mutations identified in genes with diverse functions (transcription, excitability, and energy homeostasis) for the first time provide the means to assess risk and offer insight into the molecular basis of this important clinical condition previously defined only by biophysical characteristics. © 2004 Wiley-Liss, Inc. [source] Opsin gene polymorphism predicts trichromacy in a cathemeral lemurAMERICAN JOURNAL OF PRIMATOLOGY, Issue 1 2009Carrie C. Veilleux Abstract Recent research has identified polymorphic trichromacy in three diurnal strepsirrhines: Coquerel's sifaka (Propithecus coquereli), black and white ruffed lemurs (Varecia variegata), and red ruffed lemurs (V. rubra). Current hypotheses suggest that the transitions to diurnality experienced by Propithecus and Varecia were necessary precursors to their independent acquisitions of trichromacy. Accordingly, cathemeral lemurs are thought to lack the M/L opsin gene polymorphism necessary for trichromacy. In this study, the M/L opsin gene was sequenced in ten cathemeral blue-eyed black lemurs (Eulemur macaco flavifrons). This analysis identified a polymorphism identical to that of other trichromatic strepsirrhines at the critical amino acid position 285 in exon 5 of the M/L opsin gene. Thus, polymorphic trichromacy is likely present in at least one cathemeral Eulemur species, suggesting that strict diurnality is not necessary for trichromacy. The presence of trichromacy in E. m. flavifrons suggests that a re-evaluation of current hypotheses regarding the evolution of strepsirrhine trichromacy may be necessary. Although the M/L opsin polymorphism may have been independently acquired three times in the lemurid,indriid clade, the distribution of opsin alleles in lemurids and indriids may also be consistent with a common origin of trichromacy in the last common ancestor of either the lemurids or the lemurid,indriid clade. Am. J. Primatol. 71:86,90, 2009. © 2008 Wiley-Liss, Inc. [source] The Molecular Evolution and Structural Organization of Group I Introns at Position 1389 in Nuclear Small Subunit rDNA of MyxomycetesTHE JOURNAL OF EUKARYOTIC MICROBIOLOGY, Issue 1 2007ODD-GUNNAR WIKMARK ABSTRACT. The number of nuclear group I introns from myxomycetes is rapidly increasing in GenBank as more rDNA sequences from these organisms are being sequenced. They represent an interesting and complex group of intervening sequences because several introns are mobile (or inferred to be mobile) and many contain large and unusual insertions in peripheral loops. Here we describe related group I introns at position 1389 in the small subunit rDNA of representatives from the myxomycete family Didymiaceae. Phylogenetic analyses support a common origin and mainly vertical inheritance of the intron. All S1389 introns from the Didymiaceae belong to the IC1 subclass of nuclear group I introns. The central catalytic core region of about 100 nt appears divergent in sequence composition even though the introns reside in closely related species. Furthermore, unlike the majority of group I introns from myxomycetes the S1389 introns do not self-splice as naked RNA in vitro under standard conditions, consistent with a dependence on host factors for folding or activity. Finally, the myxomycete S1389 introns are exclusively found within the family Didymiaceae, which suggests that this group I intron was acquired after the split between the families Didymiaceae and Physaraceae. [source] Origin and evolution of somatic cell testicular tumours in transgenic mice,THE JOURNAL OF PATHOLOGY, Issue 4 2010Silvina Quintana Abstract Transgenic mice bearing a construct in which the expression of the SV40 oncogene is directed by the AMH promoter (AT mice) develop testicular tumours in adult life. We aimed to study early steps of tumour development and characterize tumours at different ages by histological, morphometric, and immunohistochemical techniques. One- to 3-month-old AT mice depicted multifocal Leydig cell hyperplasia. The testicular volume occupied by interstitial tissue was significantly higher in 3-month-old AT mice in comparison with littermate controls. Between 5 1/2 and 7 months, microscopic interstitial tumours developed that progressively evolved to form large confluent areas of high mitotic index in 7- to 14-month-old AT mice. Tumour cells had the characteristics and histoarchitecture of Leydig cells, or formed solid cord-like structures reminiscent of those seen in Sertoli cell tumours. Hyperplastic areas and tumours diffusely expressed 3,-hydroxysteroid dehydrogenase (3,-HSD) in Leydig cell areas. AMH expression was negative in Leydig cell conglomerates and tumours and variable in cord-like tumours. The SV40 T antigen and markers of cell proliferation (PCNA) were intensely positive in hyperplastic cells and tumours. Control mice of similar ages showed neither hyperplasia nor tumours, and SV40 T expression was always negative. In conclusion, transgenic mice develop large testicular tumours that are preceded by interstitial hyperplasia and microtumours. The histological and immunohistochemical phenotype of tumours (Leydig and Sertoli cell differentiation, positive 3,-HSD, and variable AMH) suggests a mixed differentiation of somatic cells of the specialized gonadal stroma. The finding that an oncogene directed by a promoter specifically active in fetal Sertoli cells has given rise to testicular tumours of mixed differentiation is compatible with a common origin of Leydig and Sertoli cells from the specific stroma of the gonadal ridge, as supported by double labelling experiments in fetal mice showing co-localization of the transgene with Sertoli and Leydig cell markers. Copyright © 2010 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. [source] BNR , a LINE family from Beta vulgaris, contains a RRM domain in open reading frame 1 and defines a L1 sub-clade present in diverse plant genomesTHE PLANT JOURNAL, Issue 6 2009Tony Heitkam Summary We characterized a novel type of plant non-LTR retrotransposons, identified as the BNR family, in sugar beet (Beta vulgaris) genomes. Although their ORF2 sequences were similar to those of previously analysed LINEs (long interspersed nuclear elements) of the L1 clade, their ORF1 sequences differ strongly from those of most plant LINEs. Two novel domains were identified, containing a conserved secondary motif, known as the RNA recognition motif (RRM). ORF1 lacks the zinc finger motif that is typical of plant LINEs, but has an RRM that is likely to have a RNA-binding function. BNR LINEs are highly diverse, and were characterized by gel-blot and fluorescent in situ hybridization, showing a widespread occurrence and clustering along chromosome arms. Insertion of BNR1 into a well-described satellite repeat was detected in two cultivars only, indicating recent activity. Database searches revealed the existence of LINE families possessing an ORF1 sequence similar to that of BNR in the genomes of higher plants such as poplar, lotus and soybean. Comparing their reverse transcriptase regions with those of other retrotransposons, these LINEs were assigned to the L1 clade, but form a distinct group, providing evidence of a major separation of L1 elements in plants. This indicates a common origin of BNR-like LINEs, suggesting that these elements form a sub-clade designated as the BNR sub-clade. [source] The Living and the Lost: War and Possession in VietnamANTHROPOLOGY OF CONSCIOUSNESS, Issue 2 2007Mai Lan Gustafsson The war in Vietnam claimed the lives of five million of its citizens, many of whom died in ways thought to have turned them into malevolent spirits who prey on the living. These angry ghosts are held responsible for a host of physical ailments and other misfortunes suffered by survivors of the war and their descendants. Known in the anthropological literature as possession illness, the cross-cultural treatment for such maladies is typically provided by practitioners like mediums and exorcists, who cure victims by interacting with noncorporeal entities. In Vietnam, such spirit healers were banned after the communist takeover of the North in 1945. This has posed a problem for the large numbers of Vietnamese who suffer from ghost-induced sickness. This paper focuses on three victims of angry ghosts, presenting the common origin, context, and resolution of their suffering. In doing so, it provides an overview of Vietnamese beliefs about death and the after-life, the ideal relationship between the living and the dead, and the connection between state politics and spirit practice. [source] | |||||||||||||||||||||||||||||||