Mouse spleen lymphoblasts generated in vitro. Their replication and differentiation in vitro

Mouse spleen lymphoblasts induced with lipopolysaccharide and fetal calf serum were obtained in high yield and purity in their first proliferative cell cycle by floatation in dense bovine plasma albumin columns (3). The blasts were maintained in vitro for 3 more days. The cultures were examined in bulk on each day, and in addition, those cells in S phase initially were tagged with [(3)H]thymidine and followed continuously in vitro. Grain count dilution data indicated that most blasts divided but twice over a 2- to 3-day interval in vitro. [(3)H]Thymidine pulse radiolabeling and flow microfluorometry suggested that at least 50-70 percent of the proliferating blasts withdrew from proliferative activity after 2-3 days of culture. Morphologic studies demonstrated that lymphoblasts persisted as such for 1-2 days in vitro and then matured into typical plasma cells. Many of the blastprogeny had small nuclei and considerable basophilic cytoplasm on Giemsa-stained cell smears; abundant rough endoplasmic reticulum by electron microscopy; and readily detectable cytoplasmic Ig by immunocytochemistry. Reversion of blasts to small lymphocytes could not be detected; however, some blasts persisted even after 3 days of culture. The viability of the cultured lymphoblast was followed by initially tagging the cells with [(3)H]thymidine as well as several other techniques. Little cell death was documented during the first day of culture. The number of labeled progeny increased twofold whereas the grain count halved. But 40- 50 percent of the cell-associated label was lost during each of the second and third days, and fewer labeled progeny than predicted by grain count dilution were identified. The culture medium could not be implicated in this loss of lymphoblast progeny, and we suggest that the maturation of the lymphoblast to a short-lived plasma cell was responsible. Therefore mitogen-stimulated B blasts seem to mature into typical plasma cells after just two cycles of cell division. The plasma cells resemble those produced in situ during an immune response in their cytologic features, withdrawal from active proliferative activity, and short life-span

An Exploratory Study on the Microbiome of Northern and Southern Populations of \u3ci\u3eIxodes scapularis\u3c/i\u3e Ticks Predicts Changes and Unique Bacterial Interactions

The black-legged tick (Ixodes scapularis) is the primary vector of Borrelia burgdorferi, the causative agent of Lyme disease in North America. However, the prevalence of Lyme borreliosis is clustered around the Northern States of the United States of America. This study utilized a metagenomic sequencing approach to compare the microbial communities residing within Ix. scapularis populations from northern and southern geographic locations in the USA. Using a SparCC network construction model, we performed potential interactions between members of the microbial communities from Borrelia burgdorferi–infected tissues of unfed and blood-fed ticks. A significant difference in bacterial composition and diversity was found between northern and southern tick populations. The network analysis predicted a potential antagonistic interaction between endosymbiont Rickettsia buchneri and Borrelia burgdorferi sensu lato. The network analysis, as expected, predicted significant positive and negative microbial interactions in ticks from these geographic regions, with the genus Rickettsia, Francisella, and Borreliella playing an essential role in the identified clusters. Interactions between Rickettsia buchneri and Borrelia burgdorferi sensu lato need more validation and understanding. Understanding the interplay between the microbiome and tick-borne pathogens within tick vectors may pave the way for new strategies to prevent tick-borne infections

An Exploratory Study on the Microbiome of Northern and Southern Populations of \u3ci\u3eIxodes scapularis\u3c/i\u3e Ticks Predicts Changes and Unique Bacterial Interactions

The black-legged tick (Ixodes scapularis) is the primary vector of Borrelia burgdorferi, the causative agent of Lyme disease in North America. However, the prevalence of Lyme borreliosis is clustered around the Northern States of the United States of America. This study utilized a metagenomic sequencing approach to compare the microbial communities residing within Ix. scapularis populations from northern and southern geographic locations in the USA. Using a SparCC network construction model, we performed potential interactions between members of the microbial communities from Borrelia burgdorferi–infected tissues of unfed and blood-fed ticks. A significant difference in bacterial composition and diversity was found between northern and southern tick populations. The network analysis predicted a potential antagonistic interaction between endosymbiont Rickettsia buchneri and Borrelia burgdorferi sensu lato. The network analysis, as expected, predicted significant positive and negative microbial interactions in ticks from these geographic regions, with the genus Rickettsia, Francisella, and Borreliella playing an essential role in the identified clusters. Interactions between Rickettsia buchneri and Borrelia burgdorferi sensu lato need more validation and understanding. Understanding the interplay between the microbiome and tick-borne pathogens within tick vectors may pave the way for new strategies to prevent tick-borne infections

Parma consensus statement on metabolic disruptors

A multidisciplinary group of experts gathered in Parma Italy for a workshop hosted by the University of Parma, May 16–18, 2014 to address concerns about the potential relationship between environmental metabolic disrupting chemicals, obesity and related metabolic disorders. The objectives of the workshop were to: 1. Review findings related to the role of environmental chemicals, referred to as “metabolic disruptors”, in obesity and metabolic syndrome with special attention to recent discoveries from animal model and epidemiology studies; 2. Identify conclusions that could be drawn with confidence from existing animal and human data; 3. Develop predictions based on current data; and 4. Identify critical knowledge gaps and areas of uncertainty. The consensus statements are intended to aid in expanding understanding of the role of metabolic disruptors in the obesity and metabolic disease epidemics, to move the field forward by assessing the current state of the science and to identify research needs on the role of environmental chemical exposures in these diseases. We propose broadening the definition of obesogens to that of metabolic disruptors, to encompass chemicals that play a role in altered susceptibility to obesity, diabetes and related metabolic disorders including metabolic syndrome

The Problematization of Sexuality among Women Living with HIV and a New Feminist Approach for Understanding and Enhancing Women’s Sexual Lives

In the context of HIV, women’s sexual rights and sexual autonomy are important but frequently overlooked and violated. Guided by community voices, feminist theories, and qualitative empirical research, we reviewed two decades of global quantitative research on sexuality among women living with HIV. In the 32 studies we found, conducted in 25 countries and composed mostly of cis-gender heterosexual women, sexuality was narrowly constructed as sexual behaviours involving risk (namely, penetration) and physiological dysfunctions relating to HIV illness, with far less attention given to the fullness of sexual lives in context, including more positive and rewarding experiences such as satisfaction and pleasure. Findings suggest that women experience declines in sexual activity, function, satisfaction, and pleasure following HIV diagnosis, at least for some period. The extent of such declines, however, is varied, with numerous contextual forces shaping women’s sexual well-being. Clinical markers of HIV (e.g., viral load, CD4 cell count) poorly predicted sexual outcomes, interrupting widely held assumptions about sexuality for women with HIV. Instead, the effects of HIV-related stigma intersecting with inequities related to trauma, violence, intimate relations, substance use, poverty, aging, and other social and cultural conditions primarily influenced the ways in which women experienced and enacted their sexuality. However, studies framed through a medical lens tended to pathologize outcomes as individual “problems,” whereas others driven by a public health agenda remained primarily preoccupied with protecting the public from HIV. In light of these findings, we present a new feminist approach for research, policy, and practice toward understanding and enhancing women’s sexual lives—one that affirms sexual diversity; engages deeply with society, politics, and history; and is grounded in women’s sexual rights