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Polyploidy is considered a driving force in plant evolution and domestication. Although in the genus Arachis, several diploid species were traditionally cultivated for their seeds, only the allotetraploid peanut Arachis hypogaea became the successful, widely spread legume crop. This suggests that polyploidy has given selective advantage for domestication of peanut. Here, we study induced allotetraploid (neopolyploid) lineages obtained from crosses between the peanut's progenitor species, Arachis ipaënsis and Arachis duranensis, at earlier and later generations. We observed plant morphology, seed dimensions, and genome structure using cytogenetics (FISH and GISH) and SNP genotyping. The neopolyploid lineages show more variable fertility and seed morphology than their progenitors and cultivated peanut. They also showed sexual and somatic genome instability, evidenced by changes of number of detectable 45S rDNA sites, and extensive homoeologous recombination indicated by mosaic patterns of chromosomes and changes in dosage of SNP alleles derived from the diploid species. Genome instability was not randomly distributed across the genome: the more syntenic chromosomes, the higher homoeologous recombination. Instability levels are higher than observed on peanut lines, therefore it is likely that more unstable lines tend to perish. We conclude that early stages of the origin and domestication of the allotetraploid peanut involved two genetic bottlenecks: the first, common to most allotetraploids, is composed of the rare hybridization and polyploidization events, followed by sexual reproductive isolation from its wild diploid relatives. Here, we suggest a second bottleneck: the survival of the only very few lineages that had stronger mechanisms for limiting genomic instability., (© The Author(s) 2021. Published by Oxford University Press on behalf of Genetics Society of America.)

Objective: The angiogenic potential of endothelial progenitor cells (EPCs) may be limited by the absence of their natural biologic foundation, namely smooth muscle pericytes. We hypothesized that joint delivery of EPCs and smooth muscle cells (SMCs) in a novel, totally bone marrow-derived cell sheet will mimic the native architecture of a mature blood vessel and act as an angiogenic construct to limit post infarction ventricular remodeling., Methods: Primary EPCs and mesenchymal stem cells were isolated from bone marrow of Wistar rats. Mesenchymal stem cells were transdifferentiated into SMCs by culture on fibronectin-coated culture dishes. Confluent SMCs topped with confluent EPCs were detached from an Upcell dish to create a SMC-EPC bi-level cell sheet. A rodent model of ischemic cardiomyopathy was then created by ligating the left anterior descending artery. Rats were randomized into 3 groups: cell sheet transplantation (n = 9), no treatment (n = 12), or sham surgery control (n = 7)., Results: Four weeks postinfarction, mature vessel density tended to increase in cell sheet-treated animals compared with controls. Cell sheet therapy significantly attenuated the extent of cardiac fibrosis compared with that of the untreated group (untreated vs cell sheet, 198 degrees [interquartile range (IQR), 151-246 degrees] vs 103 degrees [IQR, 92-113 degrees], P = .04). Furthermore, EPC-SMC cell sheet transplantation attenuated myocardial dysfunction, as evidenced by an increase in left ventricular ejection fraction (untreated vs cell sheet vs sham, 33.5% [IQR, 27.8%-35.7%] vs 45.9% [IQR, 43.6%-48.4%] vs 59.3% [IQR, 58.8%-63.5%], P = .001) and decreases in left ventricular dimensions., Conclusions: The bone marrow-derived, spatially arranged SMC-EPC bi-level cell sheet is a novel, multilineage cellular therapy obtained from a translationally practical source. Interactions between SMCs and EPCs augment mature neovascularization, limit adverse remodeling, and improve ventricular function after myocardial infarction., (Copyright © 2017 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.)

Coronary artery disease is one of the most common causes of death and disability, afflicting more than 15 million Americans. Although pharmacological advances and revascularization techniques have decreased mortality, many survivors will eventually succumb to heart failure secondary to the residual microvascular perfusion deficit that remains after revascularization. We present a novel system that rescues the myocardium from acute ischemia, using photosynthesis through intramyocardial delivery of the cyanobacterium Synechococcus elongatus . By using light rather than blood flow as a source of energy, photosynthetic therapy increases tissue oxygenation, maintains myocardial metabolism, and yields durable improvements in cardiac function during and after induction of ischemia. By circumventing blood flow entirely to provide tissue with oxygen and nutrients, this system has the potential to create a paradigm shift in the way ischemic heart disease is treated.

Background: Bone marrow (BM)-derived mesenchymal stromal cells (MSCs) have shown potential to differentiate into various cell types, including smooth muscle cells (SMCs). The extracellular matrix (ECM) represents an appealing and readily available source of SMCs for use in tissue engineering. In this study, we hypothesized that the ECM could be used to induce MSC differentiation to SMCs for engineered cell-sheet construction., Methods: Primary MSCs were isolated from the BM of Wistar rats, transferred and cultured on dishes coated with 3 different types of ECM: collagen type IV (Col IV), fibronectin (FN), and laminin (LM). Primary MSCs were also included as a control. The proportions of SMC (a smooth muscle actin [aSMA] and SM22a) and MSC markers were examined with flow cytometry and Western blotting, and cell proliferation rates were also quantified., Results: Both FN and LM groups were able to induce differentiation of MSCs toward smooth muscle-like cell types, as evidenced by an increase in the proportion of SMC markers (aSMA; Col IV 42.3 ± 6.9%, FN 65.1 ± 6.5%, LM 59.3 ± 7.0%, Control 39.9 ± 3.1%; P = 0.02, SM22; Col IV 56.0 ± 7.7%, FN 74.2 ± 6.7%, LM 60.4 ± 8.7%, Control 44.9 ± 3.6%) and a decrease in that of MSC markers (CD105: Col IV 64.0 ± 5.2%, FN 57.6 ± 4.0%, LM 60.3 ± 7.0%, Control 85.3 ± 4.2%; P = 0.03). The LM group showed a decrease in overall cell proliferation, whereas FN and Col IV groups remained similar to control MSCs (Col IV, 9.0 ± 2.3%; FN, 9.8 ± 2.5%; LM, 4.3 ± 1.3%; Control, 9.8 ± 2.8%)., Conclusions: Our findings indicate that ECM selection can guide differentiation of MSCs into the SMC lineage. Fibronectin preserved cellular proliferative capacity while yielding the highest proportion of differentiated SMCs, suggesting that FN-coated materials may be facilitate smooth muscle tissue engineering., (Copyright © 2016 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.)

Objectives: We evaluated the effect of riluzole versus placebo added to weekly IM interferon beta-1a in early multiple sclerosis (MS)., Methods: This is a randomized (1:1), double-blind, placebo-controlled trial of riluzole 50 mg twice daily in subjects with MS onset less than 1 year prior. Trial participation was up to 3 years. The primary endpoint was change in percent brain volume change. Secondary endpoints included changes in normalized gray and normal-appearing white matter volumes, retinal nerve fiber layer thickness (RNFL), MS Functional Composite and Symbol Digit Modalities Test scores. Mixed model regression analysis was used to compare the changes over time between groups., Results: Forty-three subjects were randomized to study drug (22 riluzole, 21 placebo). Baseline characteristics were overall similar between groups except for older age (P = 0.042), higher normalized cerebrospinal fluid volume (P = 0.050), lower normalized gray matter volume (P = 0.14), and thinner RNFL (P = 0.043) in the riluzole group. In the primary analysis, percent brain volume change in the placebo group decreased at a rate of 0.49% per year whereas the riluzole group decreased by 0.86% per year (0.37% more per year; 95% CI -0.78, 0.024; P = 0.065). Although age did not influence the rate of brain volume decline, the difference between groups was attenuated after adjustment for baseline normalized gray matter and lesion volume (0.26% more per year in riluzole group; 95% CI -0.057, 0.014; P = 0.22). Analyses of secondary outcomes showed no differences between groups., Interpretation: This trial provides class 1 evidence that riluzole treatment does not meaningfully reduce brain atrophy progression in early MS.

Background: The genus Arachis is native to a region that includes Central Brazil and neighboring countries. Little is known about the genetic variability of the Brazilian cultivated peanut (Arachis hypogaea, genome AABB) germplasm collection at the DNA level. The understanding of the genetic diversity of cultivated and wild species of peanut (Arachis spp.) is essential to develop strategies of collection, conservation and use of the germplasm in variety development. The identity of the ancestor progenitor species of cultivated peanut has also been of great interest. Several species have been suggested as putative AA and BB genome donors to allotetraploid A. hypogaea. Microsatellite or SSR (Simple Sequence Repeat) markers are co-dominant, multiallelic, and highly polymorphic genetic markers, appropriate for genetic diversity studies. Microsatellite markers may also, to some extent, support phylogenetic inferences. Here we report the use of a set of microsatellite markers, including newly developed ones, for phylogenetic inferences and the analysis of genetic variation of accessions of A. hypogea and its wild relatives., Results: A total of 67 new microsatellite markers (mainly TTG motif) were developed for Arachis. Only three of these markers, however, were polymorphic in cultivated peanut. These three new markers plus five other markers characterized previously were evaluated for number of alleles per locus and gene diversity using 60 accessions of A. hypogaea. Genetic relationships among these 60 accessions and a sample of 36 wild accessions representative of section Arachis were estimated using allelic variation observed in a selected set of 12 SSR markers. Results showed that the Brazilian peanut germplasm collection has considerable levels of genetic diversity detected by SSR markers. Similarity groups for A. hypogaea accessions were established, which is a useful criteria for selecting parental plants for crop improvement. Microsatellite marker transferability was up to 76% for species of the section Arachis, but only 45% for species from the other eight Arachis sections tested. A new marker (Ah-041) presented a 100% transferability and could be used to classify the peanut accessions in AA and non-AA genome carriers., Conclusion: The level of polymorphism observed among accessions of A. hypogaea analyzed with newly developed microsatellite markers was low, corroborating the accumulated data which show that cultivated peanut presents a relatively reduced variation at the DNA level. A selected panel of SSR markers allowed the classification of A. hypogaea accessions into two major groups. The identification of similarity groups will be useful for the selection of parental plants to be used in breeding programs. Marker transferability is relatively high between accessions of section Arachis. The possibility of using microsatellite markers developed for one species in genetic evaluation of other species greatly reduces the cost of the analysis, since the development of microsatellite markers is still expensive and time consuming. The SSR markers developed in this study could be very useful for genetic analysis of wild species of Arachis, including comparative genome mapping, population genetic structure and phylogenetic inferences among species.

A plant of Sesbania speciosa with leaf mosaic and distortion symptoms was identified in a germ plasm regeneration plot at Griffin, Georgia. The Sesbania virus produced mild or moderate mosaic symptoms on Glycine max cvs. Bragg and Tracy M, Lupinus albus, Nicotiana benthamiana, Pisum sativum cv. Perfected Wales, Phaseolus vulgaris cvs. Black Turtle, Bountiful, and Pinto, and did not infect N. tabacum. Bean yellow mosaic potyvirus (BYMV) and pea mosaic potyvirus (PMV) do not infect Perfected Wales pea and they produce mosaic, distortion, and necrosis on white lupine. The PMV strain tested produced much more severe symptoms on the three green beans, with top necrosis on Pinto. BYMV produced local latent infection of N. tabacum and BYMV and PMV produced mosaic with distortion on N. benthamiana. The Sesbania virus was seed-transmitted at a low rate in S. speciosa. Indirect-enzyme-linked immunosorbent assay tests with a general potyvirus monoclonal antibody and BYMV and white lupine mosaic virus (WLMV) polyclonal antisera were strongly positive. Tests of the Sesbania virus against a monoclonal antibody panel suggests that it is not BYMV or any of the previously described subgroup members, but is a member of the BYMV subgroup. This is the first report of a seedborne BYMV-like virus of Sesbania spp.

Earlier this year, two surveys were conducted among healthcare providers and employers seeking their opinions regarding strategies they would employ to deal with current and expected cost pressures of the healthcare marketplace as well as healthcare value. The results of the surveys suggest that providers and employers may not be seeing the issues the same way. Providers that partner with employers will be the organizations best able to improve the quality of the care delivered--and boost their competitive positions--while the employers will receive greater value for their healthcare dollars.

A symptomless, seedborne potyvirus was isolated from guar (Cyamopsis tetragonoloba) germ plasm in Griffin, Georgia. The host range and serology were similar to those reported for guar green-sterile virus (GGSV) and guar symptomless virus. Biological, serological, and molecular comparisons of the Georgia isolate and the South African GGSV indicate they are similar and are closely related to bean common mosaic potyvirus (BCMV). The Georgia isolate is seed-transmitted at a rate of up to 94% in guar line PI 340385. Sequence analysis of the capsid protein (CP) gene and the 3'-untranslated region (3'-UTR) showed that both isolates are 96% homologous. GenBank searches indicate that both are related to various strains of BCMV. The highest CP nucleotide sequence and 3'-UTR identities of 91 and 93%, respectively, were with those of BCMV-NL4. On this basis, both isolates from guar should be considered as strains of BCMV.

Simple sequence repeats (SSRs), also known as microsatellites, are highly variable DNA sequences that can be used as markers for the genetic analysis of plants. Three approaches were followed for the development of PCR primers for the amplification of DNA fragments containing SSRs from sorghum [Sorghum bicolor (L.) Moench]: a search for sorghum SSRs in public DNA databases; the use of SSR-specific primers developed in the Poaceae species maize (Zea mays L.) and seashore paspalum grass (Paspalum vaginatum Swartz); and the screening of sorghum genomic libraries by hybridization with SSR oligonucleotides. A total of 49 sorghum SSR-specific PCR primer pairs (two designed from GenBank SSR-containing sequences and 47 from the sequences of genomic clones) were screened on a panel of 17 sorghum and one maize accession. Ten primer pairs from paspalum and 90 from maize were also screened for polymorphism in sorghum. Length polymorphisms among amplification products were detected with 15 of these primer pairs, yielding diversity values ranging from 0.2 to 0.8 with an average diversity of 0.56. These primer pairs are now available for use as markers in crop improvement and conservation efforts.

Seedlings of six species of rainforest trees with widely constrasting ecology and seed morphology were transplanted at 3 weeks of age into tree-fall gaps and the shaded understoreys at two rainforest sites (Curtain Fig and Lamins Hill) on the Atherton Tableland, North Queensland, Australia. In each forest habitat, half of the transplanted seedlings were protected from vertebrates by means of wire cages, and survival was monitored over 16 months. The main objective was to estimate the extent to which independent variables (forest, habitat, protection from vertebrates, and species) contribute to explaining survival differences among the seedlings. Significant differences existed in the mortality among species, whether caged or uncaged. Seedlings unprotected from vertebrates suffered greater mortality (i.e. averaged over all species and forests, mortality > 75%), compared to the caged seedlings (mortality < 40%). Seedling of most species survived better in forest gaps, though the effects varied significantly among the six species. Survival of caged seedlings in Curtain Fig was significantly greater than in Lamins Hill, a pattern attributed to the partial deciduousness of the Curtain Fig forest. Because only few of the uncaged seedlings survived to 16 months, we focussed on the caged seedlings to examine the role of light at the forest habitats on survival. Relationship between seedling mortality and increasing light availability vary significantly among the six species. However across species, seedling mortality decreased linearly as photosynthetically active radiation (PAR) rose from 0.48 to 2.0%, after which an asymptote was reached and further increase in light (up to 8% PAR) did not influence survival significantly. Overall, temporal, species and the various environmental variables and their interactions explained about 60% of the variations in the seedling mortality data, with protection and species differences making the greatest contributions.

A 44-year-old man with acute jejunoileitis of unknown etiology developed small bowel obstruction. Intermittent abdominal pain, bloody diarrhea, ascites, and leukocytosis were prominent features. All stool cultures were negative. On steroid treatment, symptoms and radiographic features completely resolved. We suggest, in agreement with an earlier report, that acute jejunoileitis may be regarded as a distinct clinical entity.

The different density classes of H-l parvovirus, collected within 30 hr of infection of par-asynchronous cultures, following the standard CsCl purification step, have been shown to be heterogeneous. Rebanding of the denser form (HF, p = 1.46 g/cm3) and the less dense form (LF, p = 1.42 g/cm3) of infectious virus in the nonionic density generating solute, metrizamide, showed that both HF and LF virus bands were heterogeneous in density. The infectivity banded with isotopically labeled virus protein and DNA at 1.32 g/cm3 for both HF and LF virus. Amounts of protein and DNA which varied from preparation to preparation, but which were greater from the HF virus band, were distributed throughout the rest of the gradient, but predominated in a peak at a density of 1.2 g/cm3. The protein in this peak was without hemagglutinating activity but had the molecular weights and proportions of the H-l virion proteins (VPl, VP2', and VPZ). The DNA was of the same size as H-l DNA monomers and its proportion to the protein was similar to that of the infectious peak. The DNA was susceptible to micrococcal nuclease digestion. The nature of this noninfectious viral material thus seemed to be incompletely assembled virus. Radiolabeled H-l virus collected after 72 hr of infection formed a discrete single peak in both CsCl (p = 1.42 g/cm3), and metrizamide gradients (p = 1.32 g/cm3). There was no significant amount of the 1.20 g/cm3 viral protein-DNA complex in these mature preparations.