Using phylodynamic and phylogeographic methods, Angelos Hatzakis and colleagues find that the global spread of Hepatitis C virus coincided with widespread use of transfused blood and with the expansion of intravenous drug use.

The origin of hepatitis B virus (HBV) infection in humans and other primates remains largely unresolved. Understanding the origin of HBV is crucial because it provides a framework for studying the burden, and subsequently the evolution, of HBV pathogenicity with respect to changes in human population size and life expectancy. To investigate this controversy we examined the relationship between HBV phylogeny and genetic diversity of modern humans, investigated the timescale of global HBV dispersal, and tested the hypothesis of HBV-human co-divergence. We find that the global distribution of HBV genotypes and subgenotypes are consistent with the major prehistoric modern human migrations. We calibrate the HBV molecular clock using the divergence times of different indigenous human populations based on archaeological and genetic evidence and show that HBV jumped into humans around 33,600 years ago; 95% higher posterior density (HPD): 22,000-47,100 years ago (estimated substitution rate: 2.2 3 10 26 ; 95% HPD: 1.5-3.0 3 10 26 substitutions/site/year). This coincides with the origin of modern nonAfrican humans. Crucially, the most pronounced increase in the HBV pandemic correlates with the global population increase over the last 5,000 years. We also show that the nonhuman HBV clades in orangutans and gibbons resulted from cross-species transmission events from humans that occurred no earlier than 6,100 years ago. Conclusion: Our study provides, for the first time, an estimated timescale for the HBV epidemic that closely coincides with dates of human dispersals, supporting the hypothesis that HBV has been coexpanding and co-migrating with human populations for the last 40,000 years. (HEPATO-LOGY 2013;57:908-916)

Bacteria can form single- and multispecies biofilms exhibiting diverse features based upon the microbial composition of their community and microenvironment. The study of bacterial biofilm development has received great interest in the past 20 years and is motivated by the elegant complexity characteristic of these multicellular communities and their role in infectious diseases. Biofilms can thrive on virtually any surface and can be beneficial or detrimental based upon the community's interplay and the surface. Advances in the understanding of structural and functional variations and the roles that biofilms play in disease and host-pathogen interactions have been addressed through comprehensive literature searches. In this review article, a synopsis of the methodological landscape of biofilm analysis is provided, including an evaluation of the current trends in methodological research. We deem this worthwhile because a keyword-oriented bibliographical search reveals that less than 5% of the biofilm literature is devoted to methodology. In this report, we (i) summarize current methodologies for biofilm characterization, monitoring, and quantification; (ii) discuss advances in the discovery of effective imaging and sensing tools and modalities; (iii) provide an overview of tailored animal models that assess features of biofilm infections; and (iv) make recommendations defining the most appropriate methodological tools for clinical settings.

No abstract

No abstract

No abstract

This study aims to present the origins and the historical evolution of fine-needle aspiration biopsy and to also underline its importance in the history of modern cytology. The article focuses on the advances made in the 20 th century that have led to the modern techniques associated with the procedure. The authors conducted a thorough review of early reports on needle biopsy, particularly those published during 19 th and 20 th century, examining in brief also the origins of the needle biopsy. The first report on the use of needle puncture is referred in early writings of Arab medicine. In the early 20 th century, Martin and Ellis are considered to be the founders of modern needle aspiration techniques. The German doctor Mannheim was the first to publish reports suggesting the use of fine needles with a small gauge. The establishment and world-wide expansion of FNA should be attributed to the representatives of the Swedish School of Cytopathology. The school embraced FNA in the second half of the 20 th century while serving as a training ground for doctors around the world. The history of needle biopsy spans ten centuries. However, the development and establishment of the technique in its modern form took place primarily during the twentieth century. Today, FNA is considered an important cytologic technique with sufficient diagnostic accuracy, especially when applied in cases of lung and prostate cancer.

Recombination plays a pivotal role in the evolutionary process of many different virus species, including retroviruses. Analysis of all human immunodeficiency virus type 1 (HIV-1) intersubtype recombinants revealed that they are more complex than described initially. Recombination frequency is higher within certain genomic regions, such as partial reverse transcriptase (RT ), vif/vpr, the first exons of tat/rev, vpu and gp41. A direct correlation was observed between recombination frequency and sequence similarity across the HIV-1 genome, indicating that sufficient sequence similarity is required upstream of the recombination breakpoint. This finding suggests that recombination in vivo may occur preferentially during reverse transcription through the strand displacement-assimilation model rather than the copy-choice model.