Within-guild dietary discrimination from 3-D textural analysis of tooth microwear in insectivorous mammals

Resource exploitation and competition for food are important selective pressures in animal evolution. A number of recent investigations have focused on linkages between diversification, trophic morphology and diet in bats, partly because their roosting habits mean that for many bat species diet can be quantified relatively easily through faecal analysis. Dietary analysis in mammals is otherwise invasive, complicated, time consuming and expensive. Here we present evidence from insectivorous bats that analysis of three-dimensional (3-D) textures of tooth microwear using International Organization for Standardization (ISO) roughness parameters derived from sub-micron surface data provides an additional, powerful tool for investigation of trophic resource exploitation in mammals. Our approach, like scale-sensitive fractal analysis, offers considerable advantages over twodimensional (2-D) methods of microwear analysis, including improvements in robustness, repeatability and comparability of studies. Our results constitute the first analysis of microwear textures in carnivorous mammals based on ISO roughness parameters. They demonstrate that the method is capable of dietary discrimination, even between cryptic species with subtly different diets within trophic guilds, and even when sample sizes are small. We find significant differences in microwear textures between insectivore species whose diet contains different proportions of ‘hard’ prey (such as beetles) and ‘soft’ prey (such as moths), and multivariate analyses are able to distinguish between species with different diets based solely on their tooth microwear textures. Our results show that, compared with previous 2-D analyses of microwear in bats, ISO roughness parameters provide a much more sophisticated characterization of the nature of microwear surfaces and can yield more robust and subtle dietary discrimination. ISO-based textural analysis of tooth microwear thus has a useful role to play, complementing existing approaches, in trophic analysis of mammals, both extant and extinct

Integrated Disease Investigations and Surveillance planning: a systems approach to strengthening national surveillance and detection of events of public health importance in support of the International Health Regulations

The international community continues to define common strategic themes of actions to improve global partnership and international collaborations in order to protect our populations. The International Health Regulations (IHR[2005]) offer one of these strategic themes whereby World Health Organization (WHO) Member States and global partners engaged in biosecurity, biosurveillance and public health can define commonalities and leverage their respective missions and resources to optimize interventions. The U.S. Defense Threat Reduction Agency’s Cooperative Biologica Engagement Program (CBEP) works with partner countries across clinical, veterinary, epidemiological, and laboratory communities to enhance national disease surveillance, detection, diagnostic, and reporting capabilities. CBEP, like many other capacity building programs, has wrestled with ways to improve partner country buy-in and ownership and to develop sustainable solutions that impact integrated disease surveillance outcomes. Designing successful implementation strategies represents a complex and challenging exercise and requires robust and transparent collaboration at the country level. To address this challenge, the Laboratory Systems Development Branch of the U.S. Centers for Disease Control and Prevention (CDC) and CBEP have partnered to create a set of tools that brings together key leadership of the surveillance system into a deliberate system design process. This process takes into account strengths and limitations of the existing system, how the components inter-connect and relate to one another, and how they can be systematically refined within the local context. The planning tools encourage cross-disciplinary thinking, critical evaluation and analysis of existing capabilities, and discussions across organizational and departmental lines toward a shared course of action and purpose. The underlying concepts and methodology of these tools are presented here

EL virus del HIV-1 de pacientes de May Harbor de diferentes subtipos filogenéticos: las implicancias para la evolución de la pandemia HIV/SIDA

Las variantes virales aisladas de pacientes infectados con HIV a través del mundo comparten una diversidad notable, especialmente en la glicoproteína de envoltura gp120. Los estudios filogenéticos han agrupado a los aislamientos de HIV-1 en ocho subtipos (A-H). No obstante, aún dentro de una sola persona infectada, el HIV está presente como unas «cuasi-especies,» o un enjambre de variantes estrechamente conexas. Esta diversidad genética, que en el caso del HIV-1 se acumula a una tasa de aproximadamente una sustitución de nucleótido por genoma por ciclo de replicación, da al virus una flexibilidad enorme para responder a un amplio conjunto de presiones de selección in vivo. Como una consecuencia, la droga-resistencia y las mutantes inmunológica se generan rápidamente en personas infectadas mediante todas las etapas de infección. Sobre una escala global, la pandemia del HIV se reconoce como consistiendo de muchas epidemias separadas, cada una con una geografía característica, poblaciones afectadas, y tipo predominante de cepa viral. Con unos estimados 15 millones de personas infectadas, la distribución geográfica de los subtipos virales está llegando a ser más dispersa, y estas demarcaciones son además confundidas por la evidencia creciente de infecciones mixtas.Facultad de Ciencias Veterinaria

EL virus del HIV-1 de pacientes de May Harbor de diferentes subtipos filogenéticos: las implicancias para la evolución de la pandemia HIV/SIDA

Las variantes virales aisladas de pacientes infectados con HIV a través del mundo comparten una diversidad notable, especialmente en la glicoproteína de envoltura gp120. Los estudios filogenéticos han agrupado a los aislamientos de HIV-1 en ocho subtipos (A-H). No obstante, aún dentro de una sola persona infectada, el HIV está presente como unas «cuasi-especies,» o un enjambre de variantes estrechamente conexas. Esta diversidad genética, que en el caso del HIV-1 se acumula a una tasa de aproximadamente una sustitución de nucleótido por genoma por ciclo de replicación, da al virus una flexibilidad enorme para responder a un amplio conjunto de presiones de selección in vivo. Como una consecuencia, la droga-resistencia y las mutantes inmunológica se generan rápidamente en personas infectadas mediante todas las etapas de infección. Sobre una escala global, la pandemia del HIV se reconoce como consistiendo de muchas epidemias separadas, cada una con una geografía característica, poblaciones afectadas, y tipo predominante de cepa viral. Con unos estimados 15 millones de personas infectadas, la distribución geográfica de los subtipos virales está llegando a ser más dispersa, y estas demarcaciones son además confundidas por la evidencia creciente de infecciones mixtas.Facultad de Ciencias Veterinaria

EL virus del HIV-1 de pacientes de May Harbor de diferentes subtipos filogenéticos: las implicancias para la evolución de la pandemia HIV/SIDA

Las variantes virales aisladas de pacientes infectados con HIV a través del mundo comparten una diversidad notable, especialmente en la glicoproteína de envoltura gp120. Los estudios filogenéticos han agrupado a los aislamientos de HIV-1 en ocho subtipos (A-H). No obstante, aún dentro de una sola persona infectada, el HIV está presente como unas «cuasi-especies,» o un enjambre de variantes estrechamente conexas. Esta diversidad genética, que en el caso del HIV-1 se acumula a una tasa de aproximadamente una sustitución de nucleótido por genoma por ciclo de replicación, da al virus una flexibilidad enorme para responder a un amplio conjunto de presiones de selección in vivo. Como una consecuencia, la droga-resistencia y las mutantes inmunológica se generan rápidamente en personas infectadas mediante todas las etapas de infección. Sobre una escala global, la pandemia del HIV se reconoce como consistiendo de muchas epidemias separadas, cada una con una geografía característica, poblaciones afectadas, y tipo predominante de cepa viral. Con unos estimados 15 millones de personas infectadas, la distribución geográfica de los subtipos virales está llegando a ser más dispersa, y estas demarcaciones son además confundidas por la evidencia creciente de infecciones mixtas.Facultad de Ciencias Veterinaria

Dual and recombinant infections: an integral part of the HIV-1 epidemic in Brazil.

We systematically evaluated multiple and recombinant infections in an HIV-infected population selected for vaccine trials. Seventy-nine HIV-1 infected persons in a clinical cohort study in Rio de Janeiro, Brazil, were evaluated for 1 year. A combination of molecular screening assays and DNA sequencing showed 3 dual infections (3.8%), 6 recombinant infections (7.6%), and 70 (88.6%) infections involving single viral subtypes. In the three dual infections, we identified HIV-1 subtypes F and B, F and D, and B and D; in contrast, the single and recombinant infections involved only HIV-1 subtypes B and F. The recombinants had five distinct B/F mosaic patterns: Bgag-p17/Bgag-p24/Fpol/Benv, Fgag-p17/Bgag-p24/Fpol/Fenv, Bgag-p17/B-Fgag-p24/Fpol/Fenv, Bgag-p17/B-Fgag-p24/Fpol/Benv, and Fgag-p17/B-Fgag-p24/Fpol/Fenv. No association was found between dual or recombinant infections and demographic or clinical variables. These findings indicate that dual and recombinant infections are emerging as an integral part of the HIV/AIDS epidemic in Brazil and emphasize the heterogenous character of epidemics emerging in countries where multiple viral subtypes coexist

Transmission of Human Immunodeficiency Virus Type 1 from a Seronegative Organ and Tissue Donor

Abstract BACKGROUND Since 1985, donors of organs or tissues for transplantation in the United States have been screened for human immunodeficiency virus type 1 (HIV-1), and more than 60,000 organs and 1 million tissues have been transplanted. We describe a case of transmission of HIV-1 by transplantation of organs and tissues procured between the time the donor became infected and the appearance of antibodies. The donor was a 22-year-old man who died 32 hours after a gunshot wound; he had no known risk factors for HIV-1 infection and was seronegative. METHODS We reviewed the processing and distribution of all the transplanted organs and tissues, reviewed the medical histories of the donor and HIV-1—infected recipients, tested stored donor lymphocytes for HIV-1 by viral culture and the polymerase chain reaction, and tested stored serum samples from four organ recipients for HIV-1 antigen and antibody. RESULTS HIV-1 was detected in cultured lymphocytes from the donor. Of 58 tissues and organs obtained from the donor, 52 could be accounted for by the hospitals that received them. Of the 48 identified recipients, 41 were tested for HIV-1 antibody. All four recipients of organs and all three recipients of unprocessed fresh-frozen bone were infected with HIV-1. However, 34 recipients of other tissues — 2 receiving corneas, 3 receiving lyophilized soft tissue, 25 receiving ethanol-treated bone, 3 receiving dura mater treated with gamma radiation, and 1 receiving marrow-evacuated, fresh-frozen bone — tested negative for HIV-1 antibody. Despite immunosuppressive chemotherapy, HIV-1 antibody appeared between 26 and 54 days after transplantation in the three organ recipients who survived more than 4 weeks. CONCLUSIONS Although rare, transmission of HIV-1 by seronegative organ and tissue donors can occur. Improvements in the methods used to screen donors for HIV-1, advances in techniques of virus inactivation, prompt reporting of HIV infection in recipients, and accurate accounting of distributed allografts would help to reduce further this already exceedingly low risk. (N Engl J Med 1992;326:726–32.

Sequencing three crocodilian genomes to illuminate the evolution of archosaurs and amniotes

The International Crocodilian Genomes Working Group (ICGWG) will sequence and assemble the American alligator (Alligator mississippiensis), saltwater crocodile (Crocodylus porosus) and Indian gharial (Gavialis gangeticus) genomes. The status of these projects and our planned analyses are described