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This page intentionally left blank Cambridge Studies in Biological and Evolutionary Anthropology 38Neanderthals and Modern HumansNeanderthals and Modern Humans develops the theme of the closerelationship between climate change, ecological change and biogeo-graphical patterns in humans during the Pleistocene. In particular, itchallengesthe view that Modern Human ‘superiority’ caused the ex-tinction of the Neanderthals between 40 000 and 30 000 years ago.Clive Finlayson shows that to understand human evolution,the spreadof humankind across the world and the extinction of archaic popula-tions we must start off from a theoretical evolutionary ecology baseand incorporate the important wider biogeographic patterns, includingthe role of tropical and temperate refugia. His proposalis that Nean-derthals became extinct because their world changed faster than theycould cope with, and that their relationship with the arrivingModernHumans, where they met, was subtle.Clive Finlaysonis Director, Museums and Heritage in the Govern-ment of Gibraltar, based at the Gibraltar Museum. He is also Professorin the Department of Anthropology at the University of Toronto. Hisresearch interests include Quaternary human–environmental patterns,the biogeography of hominids, and changing environments and faunalpatterns in the Quaternary of southern Europe. Cambridge Studies in Biological and Evolutionary AnthropologySeries Editorshuman ecologyC. G. Nicholas Mascie-Taylor, University of CambridgeMichael A. Little, State University of New York, BinghamtongeneticsKenneth M. Weiss, Pennsylvania State Universityhuman evolutionRobertA. Foley, University ofCambridgeNina G. Jablonski,California Academy of ScienceprimatologyKaren B. Strier, University of Wisconsin, MadisonSelected titles also in the series21 Bioarchaeology Clark S. Larsen 0 521 49641 (hardback), 0 521 65834 9 (paperback)22 Comparative Primate Socioecology P. C. Lee (ed.) 0 521 59336 0 (hardback)0 521 00424 1 (paperback)23 Patterns of Human Growth, second edition Barry Bogin 0 521 56438 7 (paperback)24 Migration and Colonisation in Human Microevolution Alan Fix 0 521 59206 225 Human Growth in the Past Robert D. Hoppa & Charles M. FitzGerald (eds)0 521 63153 X26 Human Paleobiology Robert B. Eckhardt 0 521 45160 427 Mountain Gorillas Martha M. Robbins, Pascale Sicotte & Kelly J. Stewart (eds)0 521 76004 728 Evolution and Genetics of Latin American Populations Francisco M. Salzano &Maria C. Bortolini 0 521 65275 829 Primates Face to Face Agust´ın Fuentes & Linda D. Wolfe (eds) 0 521 79109 X30 Human Biology of Pastoral Populations William Leonard & Michael Crawford(eds) 0 521 78016 031 Paleodemography Robert D. Hoppa & James W. Vanpel (eds) 0 521 80063 3132 Primate Dentition Davis Swindler 0 521 65289 833 The Primate Fossil Record Walter C. Hartwig (ed.) 0 521 66315 634 Gorilla Biology Andrea B. Taylor & Michele L. Goldsmith (eds) 0 521 79281 935 Human Biologists in the Archives D. Ann Hening & Alan C. Swedlund (eds)0 521 80104 436 Human Senescence Douglas Crews 0 521 57173 137 Patterns of Growth and Development in the Genus Homo Jennifer L. Thompson,Gail E. Krovitz & Andrew J. Nelson (eds) 0 521 57173 1 Neanderthals andModern HumansAn Ecological and Evolutionary PerspectiveCLIVE FINLAYSONThe Gibraltar MuseumandThe University of Toronto cambridge university pressCambridge, New York, Melbourne, Madrid, Cape Town, Singapore, São PauloCambridge University PressThe Edinburgh Building, Cambridge cb2 2ru, UKFirst published in print format isbn-13 978-0-521-82087-5isbn-13 978-0-511-18634-9© Clive Finlayson 20042004Information on this title: www.cambridge.org/9780521820875This publication is in copyright. Subject to statutory exception and to the provision ofrelevant collective The Human Population The Human Population Bởi: OpenStaxCollege Concepts of animal population dynamics can be applied to human population growth Humans are not unique in their ability to alter their environment For example, beaver dams alter the stream environment where they are built Humans, however, have the ability to alter their environment to increase its carrying capacity, sometimes to the detriment of other species Earth’s human population and their use of resources are growing rapidly, to the extent that some worry about the ability of Earth’s environment to sustain its human population Long-term exponential growth carries with it the potential risks of famine, disease, and large-scale death, as well as social consequences of crowding such as increased crime Human technology and particularly our harnessing of the energy contained in fossil fuels have caused unprecedented changes to Earth’s environment, altering ecosystems to the point where some may be in danger of collapse Changes on a global scale including depletion of the ozone layer, desertification and topsoil loss, and global climate change are caused by human activities The world’s human population is presently growing exponentially ([link]) Human population growth since 1000 AD is exponential A consequence of exponential growth rate is that the time that it takes to add a particular number of humans to the population is becoming shorter [link] shows that 123 years 1/7 The Human Population were necessary to add billion humans between 1804 and 1930, but it only took 24 years to add the two billion people between 1975 and 1999 This acceleration in growth rate will likely begin to decrease in the coming decades Despite this, the population will continue to increase and the threat of overpopulation remains, particularly because the damage caused to ecosystems and biodiversity is lowering the human carrying capacity of the planet The time between the addition of each billion human beings to Earth decreases over time (credit: modification of work by Ryan T Cragun) Concept in Action Click through this interactive view of how human populations have changed over time Overcoming Density-Dependent Regulation Humans are unique in their ability to alter their environment in myriad ways This ability is responsible for human population growth because it resets the carrying capacity and overcomes density-dependent growth regulation Much of this ability is related to human intelligence, society, and communication Humans construct shelters to protect themselves from the elements and have developed agriculture and domesticated animals to increase their food supplies In addition, humans use language to communicate this technology to new generations, allowing them to improve upon previous accomplishments 2/7 The Human Population Other factors in human population growth are migration and public health Humans originated in Africa, but we have since migrated to nearly all inhabitable land on Earth, thus, increasing the area that we have colonized Public health, sanitation, and the use of antibiotics and vaccines have decreased the ability of infectious disease to limit human population growth in developed countries In the past, diseases such as the bubonic plaque of the fourteenth century killed between 30 and 60 percent of Europe’s population and reduced the overall world population by as many as one hundred million people Infectious disease continues to have an impact on human population growth For example, life expectancy in sub-Saharan Africa, which was increasing from 1950 to 1990, began to decline after 1985 largely as a result of HIV/AIDS mortality The reduction in life expectancy caused by HIV/AIDS was estimated to be years for 2005 Danny Dorling, Mary Shaw, and George Davey Smith, “Global Inequality of Life Expectancy due to AIDS,” BMJ 332, no 7542 (March 2006): 662-664, doi: 10.1136/ bmj.332.7542.662 Declining life expectancy is an indicator of higher mortality rates and leads to lower birth rates The fundamental cause of the acceleration of growth rate for humans in the past 200 years has been the reduced death rate due to a development of the technological advances of the industrial age, urbanization that supported those technologies, and especially the exploitation of the energy in fossil fuels Fossil fuels are responsible for dramatically increasing the resources available for human population growth through agriculture (mechanization, pesticides, and fertilizers) and harvesting wild populations Age Structure, Population Growth, and Economic Development The age structure of a population is an important factor in population dynamics Age structure is the proportion of a population in different age classes Models that incorporate age structure allow better prediction of population growth, plus the ability to associate this growth with the level of economic development in a region Countries with rapid growth have a pyramidal shape in their age structure ...Int. J. Med. Sci. 2004 1(3): 146-151 146 International Journal of Medical Sciences ISSN 1449-1907 www.medsci.org 2004 1(3): 146-151 ©2004 Ivyspring International Publisher. All rights reserved Expression of hMSH2 protein of the human DNA mismatch repair system in oral lichen planus Research paper Received: 2004.4.27 Accepted: 2004.6.28 Published: 2004.8.05 Flávio Juliano Garcia Santos Pimenta1, Maria das Graças Rodrigues Pinheiro2, Ricardo Santiago Gomez1 1 Department of Oral Surgery and Pathology, School of Dentistry, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil. 2 School of Dentistry, Centro de Ensino Superior do Pará, Belém, Brazil. AAbbssttrraacctt Lichen planus is a mucocutaneous disease of inflammatory nature and unknown etiology. It is characterized by a cell-mediated immunological response to induced antigenic change in skin and/or mucosa. The possible malignant transformation of lichen planus remains a subject of controversial discussions in the literature. hMSH2 is one of the human DNA mismatch repair (hMMR) genes and it plays an important role in reducing mutation and maintaining genomic stability. hMSH2 alterations have been reported in oral squamous cell carcinoma and there are evidences suggesting the association between oral lichen planus and squamous cell carcinoma. In this study, we aim to investigate the immunolocalization of hMSH2 protein in oral lichen planus compared to oral normal mucosa epithelium. We examined the expression of hMSH2 protein by immunohistochemistry in twenty-six cases of oral lichen planus. Clinically, 12 of them were categorized into reticular subtype and 14 were atrophic/erosive. Ten cases of normal mucosa were added to the control group. Results showed that the percentage of positive cells to hMSH2 was smaller in reticular (46.54%; p=0,006) and atrophic/erosive (48.79%; p=0,028) subtypes of oral lichen planus compared to normal mucosa (61.29%). The reduced expression of hMSH2 protein in oral lichen planus suggests that this lesion is more susceptible to mutation and therefore facilitate the development of oral squamous cell carcinoma. KKeeyy wwoorrddss hMSH2, immunohistochemistry, oral lichen planus and malignant transformation AAuutthhoorr bbiiooggrraapphhyy Flávio Juliano Garcia Santos Pimenta, DDS, is pursuing postgraduate study at the School of Dentistry, Universidade Federal de Minas Gerais. His research interests include molecular analysis of genes associated with oral diseases. His current work is in the analysis of wwox gene in oral cancer. Maria das Graças Rodrigues Pinheiro, DDS, has concluded her MS at the School of Dentistry, Universidade Federal de Minas Gerais and is lecturer at Centro de Ensino Superior do Pará (CESUPA), Belém. Her research interests include radiographic investigation of oral diseases. Her current work is in radiographic analysis of odontogenic tumors. Ricardo Santiago Gomez, DDS MS PhD, is Professor in Oral Pathology and Director of School of Dentistry, Universidade Federal de Minas Gerais and research fellow of Conselho Nacional de Desenvolvimento Científico e Tecnológico. His research interests include molecular analysis of genes associated with oral diseases. He BioMed Central Page 1 of 12 (page number not for citation purposes) Virology Journal Open Access Research Evolution of naturally occurring 5'non-coding region variants of Hepatitis C virus in human populations of the South American region Gonzalo Moratorio 1 , Mariela Martínez 1 , María F Gutiérrez 2 , Katiuska González 3 , Rodney Colina 6 , Fernando López-Tort 1 , Lilia López 1 , Ricardo Recarey 1 , Alejandro G Schijman 4,5 , María P Moreno 1 , Laura García- Aguirre 1 , Aura R Manascero 2 and Juan Cristina* 1 Address: 1 Laboratorio de Virología Molecular. Centro de Investigaciones Nucleares. Facultad de Ciencias, Iguá 4225, 11400 Montevideo, Uruguay, 2 Laboratorio de Virología, Departamento de Microbiología, Facultad de Ciencias, Pontificia Universidad Javeriana, Cra 7 # 43-82 Ed 50 of 313, Bogotá, Colombia, 3 Facultad de Ciencias Médicas y Bioquímicas, Universidad Mayor de San Andrés, Av. Villazón No. 1995 Monoblock Central, La Paz, Bolivia, 4 Laboratorio de Biología Molecular, Grupo CentraLab, Buenos Aires, Argentina, 5 Instituto de Investigaciones en Ingeniería Genética y Biología Molecular, Vuelta de Obligado 2490, Second Floor, 1428 Buenos Aires, Argentina and 6 Department of Biochemistry and McGill Cancer Center, McGill University, Montreal, Quebec, Canada H3G 1Y6 Email: Gonzalo Moratorio - gmora@cin.edu.uy; Mariela Martínez - marie@cin.edu.uy; María F Gutiérrez - mfgutier@javeriana.edu.co; Katiuska González - katiuskagg@hotmail.com; Rodney Colina - rcolina@cin.edu.uy; Fernando López-Tort - flopez@cin.edu.uy; Lilia López - llopez@cin.edu.uy; Ricardo Recarey - rrecarey@cin.edu.uy; Alejandro G Schijman - schijman@dna.uba.ar; María P Moreno - pmoreno@cin.edu.uy; Laura García-Aguirre - lgarcia@cin.edu.uy; Aura R Manascero - mfgutier@javeriana.edu.co; Juan Cristina* - cristina@cin.edu.uy * Corresponding author Abstract Background: Hepatitis C virus (HCV) has been the subject of intense research and clinical investigation as its major role in human disease has emerged. Previous and recent studies have suggested a diversification of type 1 HCV in the South American region. The degree of genetic variation among HCV strains circulating in Bolivia and Colombia is currently unknown. In order to get insight into these matters, we performed a phylogenetic analysis of HCV 5' non- coding region (5'NCR) sequences from strains isolated in Bolivia, Colombia and Uruguay, as well as available comparable sequences of HCV strains isolated in South America. Methods: Phylogenetic tree analysis was performed using the neighbor-joining method under a matrix of genetic distances established under the Kimura-two parameter model. Signature pattern analysis, which identifies particular sites in nucleic acid alignments of variable sequences that are distinctly representative relative to a background set, was performed using the method of Korber & Myers, as implemented in the VESPA program. Prediction of RNA secondary structures was done by the method of Zuker & Turner, as implemented in the mfold program. Results: Phylogenetic tree analysis of HCV strains isolated in the South American region revealed the presence of a distinct genetic lineage inside genotype 1. Signature pattern analysis revealed that the presence of this lineage is consistent with the presence of a sequence signature in the 5'NCR of HCV strains isolated in South America. Comparisons of these results with the ones BioMed Central Page 1 of 12 (page number not for citation purposes) Virology Journal Open Access Research Evolution of naturally occurring 5'non-coding region variants of Hepatitis C virus in human populations of the South American region Gonzalo Moratorio 1 , Mariela Martínez 1 , María F Gutiérrez 2 , Katiuska González 3 , Rodney Colina 6 , Fernando López-Tort 1 , Lilia López 1 , Ricardo Recarey 1 , Alejandro G Schijman 4,5 , María P Moreno 1 , Laura García- Aguirre 1 , Aura R Manascero 2 and Juan Cristina* 1 Address: 1 Laboratorio de Virología Molecular. Centro de Investigaciones Nucleares. Facultad de Ciencias, Iguá 4225, 11400 Montevideo, Uruguay, 2 Laboratorio de Virología, Departamento de Microbiología, Facultad de Ciencias, Pontificia Universidad Javeriana, Cra 7 # 43-82 Ed 50 of 313, Bogotá, Colombia, 3 Facultad de Ciencias Médicas y Bioquímicas, Universidad Mayor de San Andrés, Av. Villazón No. 1995 Monoblock Central, La Paz, Bolivia, 4 Laboratorio de Biología Molecular, Grupo CentraLab, Buenos Aires, Argentina, 5 Instituto de Investigaciones en Ingeniería Genética y Biología Molecular, Vuelta de Obligado 2490, Second Floor, 1428 Buenos Aires, Argentina and 6 Department of Biochemistry and McGill Cancer Center, McGill University, Montreal, Quebec, Canada H3G 1Y6 Email: Gonzalo Moratorio - gmora@cin.edu.uy; Mariela Martínez - marie@cin.edu.uy; María F Gutiérrez - mfgutier@javeriana.edu.co; Katiuska González - katiuskagg@hotmail.com; Rodney Colina - rcolina@cin.edu.uy; Fernando López-Tort - flopez@cin.edu.uy; Lilia López - llopez@cin.edu.uy; Ricardo Recarey - rrecarey@cin.edu.uy; Alejandro G Schijman - schijman@dna.uba.ar; María P Moreno - pmoreno@cin.edu.uy; Laura García-Aguirre - lgarcia@cin.edu.uy; Aura R Manascero - mfgutier@javeriana.edu.co; Juan Cristina* - cristina@cin.edu.uy * Corresponding author Abstract Background: Hepatitis C virus (HCV) has been the subject of intense research and clinical investigation as its major role in human disease has emerged. Previous and recent studies have suggested a diversification of type 1 HCV in the South American region. The degree of genetic variation among HCV strains circulating in Bolivia and Colombia is currently unknown. In order to get insight into these matters, we performed a phylogenetic analysis of HCV 5' non- coding region (5'NCR) sequences from strains isolated in Bolivia, Colombia and Uruguay, as well as available comparable sequences of HCV strains isolated in South America. Methods: Phylogenetic tree analysis was performed using the neighbor-joining method under a matrix of genetic distances established under the Kimura-two parameter model. Signature pattern analysis, which identifies particular sites in nucleic acid alignments of variable sequences that are distinctly representative relative to a background set, was performed using the method of Korber & Myers, as implemented in the VESPA program. Prediction of RNA secondary structures was done by the method of Zuker & Turner, as implemented in the mfold program. Results: Phylogenetic tree analysis of HCV strains isolated in the South American region revealed the presence of a distinct genetic lineage inside genotype 1. Signature pattern analysis revealed that the presence of this lineage is consistent with the presence of a sequence signature in the 5'NCR of HCV strains isolated in South America. Comparisons of these results with the ones COMM E N T ARY Open Access Detection of a gammaretrovirus, XMRV, in the human population: Open questions and implications for xenotransplantation Joachim Denner Abstract XMRV (xenotropic murine leukaemia virus-related virus) is a gammaretrovirus that has been detected in human patients with prostate carcinoma, chronic fatigue syndrome (CFS) and also in a small percentage of clinically healthy individuals. It is not yet clear whether the distribution of this virus is primarily limited to the USA or whether it is causally associated with human disease. If future investigations confirm a broad distribution of XMRV and its association with disease, this would have an impact on xenotransplantation of porcine tissues and organs. Xenotransplantation is currently being developed to compensate for the increasing shortage of human material for the treatment of tissue and organ failure but could result in the transmission of porcine pathogens. Maintenance of pathogen-free donor animals will dramatically reduce this risk, but some of the porcine endogen ous retroviruses (PERVs) found in the genome of all pigs, can produce infectious virus and infect cultured human cells. PERVs are closely related to XMRV so it is critical to develop tests that discriminate between them. Since recombination can occur between viruses, and recombinants can exhibit synergism, recipients sho uld be tested for XMRV before xenotransplantation. Questions concerning XMRV detection XMRV was first detected in prostate carcinomas of patients who were homozygous for a mutation in the gen e for the antiviral enzym e, ribonuclease L (RNase L) [1]. Men with two copies of the homozygous m utation R462Q (QQ) were found to have twice the risk of pros- tate cancer as males with the non-mutated allele. Inte- grated XMRV was detected in 8 of 20 of these patients (40%) using a DNA microarray and RT-PCR analysis. In heterozygous patients and patients without the muta- tion, XMRV was found only in 1.5% of prostate tumours. The sequence of the virus is closely related (more than 93% DNA sequence identity) to other xeno- tropic murine retroviruses. Xenotropic viruses infect only cells from other species. Interestin gly, low levels of XMRV protein expression were detected in a small number of stromal cells, but not in the tumour cells themselves. In vitro tests have revealed that the virus productively infects human cells and that its replication is susceptible to IFN-b treatment [2]. Another study identified XMRV proviral DNA in 6% of the prostate tumours analysed by real time P CR and viral protein was detected in 23% of 334 prostate tumours using anti- sera against a panel of murine retroviruses including XMRV [3]. In that study, infection w as associated with high-grade tumours, but did not correlate with the RNase L QQ variant. In contrast to previous reports [1], XMRV proteins were found to be expressed primarily in tumour cells [3]. Unfortunately screening for XMRV specific antibodies was not performed, although it is generally agreed that detection of antibodies is a com- mon and reliable diagnostic method to detect low level infections with retroviruses including HIV-1. In cases of low proviral loa d, anti body detection can indicate infec- tion in the absence of positive PCR results [4]. In Europe, XMRV appears to be less common than in the USA. No XMRV was found in 139 Irish prostate cancer patients with the RNase L mutation [5]. In a German study, XMRV-specific sequences were det ected in only in 1 of 105 tissue samples from non-familial prostate cancer and in 1 of 70 tissue samples from men without prostate cancer [6]. The two positive samples Correspondence: DennerJ@rki.de Retrovirus induced immunosuppression, Robert Koch Institute, Nordufer 20, D-13353 Berlin, Germany Denner Retrovirology 2010, 7:16 http://www.retrovirology.com/content/7/1/16 © 2010 Denner; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons ... Exponential Human Population Growth Many dire predictions have been made about the world’s population leading to a major crisis called the population explosion.” In the 1968 book The Population. .. people by the year 2100 There is no way to know whether human population growth will moderate to the point where the crisis described by Dr Ehrlich will be averted Another consequence of population. .. new generations, allowing them to improve upon previous accomplishments 2/7 The Human Population Other factors in human population growth are migration and public health Humans originated in Africa,

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