The slick hair coat locus maps to chromosome 20 in Senepol-derived cattle.

The ability to maintain normal temperatures during heat stress is an important attribute for cattle in the subtropics and tropics. Previous studies have shown that Senepol cattle and their crosses with Holstein, Charolais and Angus animals are as heat tolerant as Brahman cattle. This has been attributed to the slick hair coat of Senepol cattle, which is thought to be controlled by a single dominant gene.

Genetic diversity among Angus, American Brahman, Senepol and Romosinuano cattle breeds.

The objective of this study was to quantify the genetic diversity among breeds under evaluation for tropical adaptability traits that affect the performance of beef cattle at the USDA/ARS SubTropical Agricultural Research Station (STARS) near Brooksville, FL, USA. Twenty-six microsatellite loci were used to estimate parameters of genetic diversity among the breeds American Brahman, Angus, Senepol and Romosinuano; the latter was comprised of two distinct bloodlines (Costa Rican and Venezuelan). Genotypes of 47 animals from each of these STARS herds were analysed for genetic diversity and genetic distance.

Evaluation of birth and weaning traits of Romosinuano calves as purebreds and crosses with Brahman and Angus.

The objectives of this work were to evaluate birth and weaning traits, to estimate genetic effects, including heterosis and direct and maternal breed effects, and to evaluate calving difficulty, calf vigor at birth, and calf mortality of Romosinuano as purebreds and as crosses with Brahman and Angus. Calves (n = 1,348) were spring-born from 2002 through 2005 and weaned in the fall of each year at about 7 mo of age. Traits evaluated included birth and weaning weight, ADG, BCS, and weaning hip height.

Chronic cardiac transplant arteriopathy in mice: relationship of alloantibody, C4d deposition and neointimal fibrosis.

Murine heterotopic cardiac allografts were used to reveal some of the fundamental interrelationships between donor-specific alloantibodies (DSA), chronic transplant arteriopathy (CTA) and capillary C4d deposition. B10.BR recipients of B10.

Cytoplasmic male sterility: a window to the world of plant mitochondrial-nuclear interactions.

Mitochondrial function depends on the coordinate action of nuclear and mitochondrial genomes. The genetic dissection of these interactions presents special challenges in obligate aerobes, because the viability of these organisms depends on mitochondrial respiration. The plant trait cytoplasmic male sterility (CMS) is determined by the mitochondrial genome and is associated with a pollen sterility phenotype that can be suppressed or counteracted by nuclear genes known as restorer-of-fertility genes.

Genetic parameters for body weight, hip height, and the ratio of weight to hip height from random regression analyses of Brahman feedlot cattle.

The objective of this research was to assess the genetic control of BW, hip height, and the ratio of BW to hip height (n = 5,055) in Brahman cattle through 170 d on feed using covariance function-random regression models. A progeny test of Brahman sires (n = 27) generated records of Brahman steers and heifers (n = 724) over 7 yr. Each year after weaning, calves were assigned to feedlot pens, where they were fed a high-concentrate grain diet.

T-cell depletion eliminates the development of cardiac allograft vasculopathy in mice rendered tolerant by the induction of mixed chimerism.

We previously demonstrated that cardiac allografts to fully tolerant chimeric mice developed cardiac allograft vasculopathy (CAV). Here we begin to examine which components of the immune system are responsible for the pathogenesis of CAV in such tolerant recipients. B10.

Naive recirculating B cells mature simultaneously in the spleen and bone marrow.

We have recently demonstrated that IgD(hi) B cells can occupy an extravascular perisinusoidal niche in the bone marrow in addition to the well-established follicular niche in conventional secondary lymphoid organs. The spleen has long been considered to be the site at which newly formed B lymphocytes mature into IgD(hi) naive recirculating B cells, but the existence of mutant mice that have selectively lost mature B cells in the bone marrow prompted an examination of B-cell maturation at this latter site. Following a single pulse of BrdU in intact mice, sequential labeling of more mature B-cell populations in the bone marrow suggested ongoing maturation at this site.

Oligonucleotide fingerprint identification for microarray-based pathogen diagnostic assays.

Motivation: Advances in DNA microarray technology and computational methods have unlocked new opportunities to identify 'DNA fingerprints', i.e. oligonucleotide sequences that uniquely identify a specific genome.

Evaluation of protection against virulent bovine viral diarrhea virus type 2 in calves that had maternal antibodies and were vaccinated with a modified-live vaccine.

Objective: To evaluate the efficacy of an adjuvanted modified-live bovine viral diarrhea virus (BVDV) vaccine against challenge with a virulent type 2 BVDV strain in calves with or without maternal antibodies against the virus.

Design: Challenge study.

Animals: 23 crossbred dairy calves.

Protection against fetal infection with either bovine viral diarrhea virus type 1 or type 2 using a noncytopathic type 1 modified-live virus vaccine.

Two bovine viral diarrhea virus (BVDV) fetal protection studies were done using a monovalent noncytopathic (NCP) BVDV vaccine containing type 1 BVDV. In study 1, thirty-two fetuses (23 vaccinates and nine controls) were recovered following fetal challenge with the type 1a BJ strain. Twenty of twenty-three fetuses from the vaccinates were negative for BVDV type 1 while all of the controls (nine of nine) were infected.

The changing role of natural killer cells in solid organ rejection and tolerance.

Natural killer (NK) cells have emerged as a particular focus of interest in transplantation due to their ability to distinguish allogeneic major histocompatibility complex (MHC) antigens and their potent cytolytic effector mechanisms. Once relegated to the field of bone marrow transplantation, NK cells have recently been shown to participate in the immune response against solid organ allo- and xenografts. These new findings suggest that the role of NK cells in solid organ rejection and tolerance needs to be reexamined.

Effects of perinatal HIV infection and associated risk factors on cognitive development among young children.

Objective: We examined the effect of HIV, in combination with other important health and social factors, on the development of cognitive abilities of children perinatally exposed to HIV.

Methods: Serial cognitive assessments were performed for 117 children who were infected vertically and 422 children who were exposed to but not infected with HIV, in a multicenter, natural history, longitudinal study. Repeated-measures analyses were used to evaluate the neurocognitive development of children between the ages of 3 and 7 years, as measured by the McCarthy Scales of Children's Abilities (MSCA).

Effects of calpastatin and micro-calpain markers in beef cattle on tenderness traits.

The objective of this study was to assess the association of single nucleotide polymorphisms (SNP) developed at the calpastatin (CAST) and mu-calpain (CAPN1) genes with meat tenderness and palatability traits in populations with diverse genetic backgrounds. Three populations were used in the study. One population consisted of Bos taurus that included crossbred animals derived from Hereford, Angus, Red Angus, Limousin, Charolais, Gelbvieh, and Simmental (GPE7; n = 539).

Dorsal stream associations with orthographic and phonological processing.

Several studies have indicated a key role for dorsal stream processing in lexical decoding. To examine this relationship further, performance on orthographic and phonological reading tests was compared with both steady-state visual evoked potentials and a putative behavioral measure of dorsal stream processing, coherent motion detection. Frequency analysis of the visual evoked potential data showed power at the second harmonic to be largely confined to dorsal stream regions, and significantly correlated with motion detection thresholds.

Genetically engineered cytoplasmic male sterility.

Cytoplasmic male sterility, conditioned by some maternally inherited plant mitochondrial genomes, is the most expedient method to produce uniform populations of pollen-sterile plants on a commercial scale. Plant mitochondrial genomes are not currently amenable to genetic transformation, but genetic manipulation of the plastid genome allows engineering of maternally inherited traits in some species. A recent study has shown that the Acinetobacter beta-ketothiolase gene, expressed in the Nicotiana tabacum plastid, conditions maternally inherited male sterility, laying the groundwork for new approaches to control pollen fertility in crop plants.

Perisinusoidal B cells in the bone marrow participate in T-independent responses to blood-borne microbes.

Mature recirculating B cells are generally assumed to exist in follicular niches in secondary lymphoid organs, and these cells mediate T-dependent humoral immune responses. We show here that a large proportion of mature B lymphocytes occupy an anatomically and functionally distinct perisinusoidal niche in the bone marrow. Perisinusoidal B cells circulate freely, as revealed by parabiosis studies.

Changing the nomenclature/taxonomy for intersex: a scientific and clinical rationale.

We explain here why the standard division of many intersex types into true hermaphroditism, male pseudohermaphroditism, and female pseudohermaphroditism is scientifically specious and clinically problematic. First we provide the history of this tripartite taxonomy and note how the taxonomy predates and largely ignores the modern sciences of genetics and endocrinology. We then note the numerous ways that the existing taxonomy confuses and sometimes harms clinicians, researchers, patients, and parents.

Activation of bone marrow-resident memory T cells by circulating, antigen-bearing dendritic cells.

Dendritic cells (DCs) carry antigen from peripheral tissues via lymphatics to lymph nodes. We report here that differentiated DCs can also travel from the periphery into the blood. Circulating DCs migrated to the spleen, liver and lung but not lymph nodes.

NK cells can trigger allograft vasculopathy: the role of hybrid resistance in solid organ allografts.

Progressive arterial stenosis (cardiac allograft vasculopathy (CAV)) is a leading cause of long-term failure of organ transplants. CAV remains intractable, in part because its mechanisms are insufficiently understood. A central proposition is that MHC-driven alloimmune processes play a necessary role in CAV, as shown by the absolute requirement for histoincompatibility between donor and recipient for its production.

A new single nucleotide polymorphism in CAPN1 extends the current tenderness marker test to include cattle of Bos indicus, Bos taurus, and crossbred descent.

The three objectives of this study were to 1) test for the existence of beef tenderness markers in the CAPN1 gene segregating in Brahman cattle; 2) test existing CAPN1 tenderness markers in indicus-influenced crossbred cattle; and 3) produce a revised marker system for use in cattle of all subspecies backgrounds. Previously, two SNP in the CAPN1 gene have been described that could be used to guide selection in Bos taurus cattle (designated Markers 316 and 530), but neither marker segregates at high frequency in Brahman cattle. In this study, we examined three additional SNP in CAPN1 to determine whether variation in this gene could be associated with tenderness in a large, multisire American Brahman population.

Real-time PCR assays targeting a unique chromosomal sequence of Yersinia pestis.

Background: Yersinia pestis, the causative agent of the zoonotic infection plague, is a major concern as a potential bioweapon. Current real-time PCR assays used for Y. pestis detection are based on plasmid targets, some of which may generate false-positive results.

Factors influencing tenderness in steaks from Brahman cattle.

The objective of this study was to identify a set of explanatory variables for Warner-Bratzler shear force and myofibril fragmentation indices after 7, 14, and 21d of aging; and sensory tenderness after 14d of aging of steaks from Brahman cattle. Insoluble collagen was negatively associated (P<0.001) with all tenderness traits across aging periods, and regression coefficients ranged from 5.