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Effects of concentrate crude protein content on nutrient digestibility, energy utilization, and methane emissions in lactating dairy cows fed fresh-cut perennial grass
Although many studies have investigated mitigation strategies for methane (CH4) output from dairy cows fed a wide variety of diets, research on effects of concentrate crude protein (CP) content on CH4 emissions from dairy cows offered fresh grass is limited. The present study was therefore designed to evaluate effects of cow genotype and concentrate CP level on nutrient digestibility, energy utilization and CH4 emissions of dairy cows offered fresh grass based diets. Twelve multiparous lactating dairy cows (6 Holstein and 6 Holstein × Swedish Red) were blocked into 3 groups within each breed and assigned to low, medium or high CP concentrate diet (14.1, 16.1 and 18.1 % on dry matter (DM) basis), respectively, in a 3-period changeover study (25-d / period). Total diets contained (DM basis) 32.8 % concentrates and 67.2 % perennial ryegrass, which was harvested daily. All measurements were undertaken during the final 6-d of each period; digestibility measurements for 6-d and calorimetric measurements in respiration chambers for 3-d. Feed intake and milk production data were reported in a previous paper. No significant interaction between concentrate CP level and cow genotype on any parameter was observed. Concentrate CP level had no significant effect on any energy utilization parameter, except for urinary energy output which was positively related to concentrate CP level. Similarly concentrate CP content had no effect on CH4 emission (g/d), CH4 per kg feed intake or nutrient digestibility. The crossbreeding of Holstein cows significantly reduced gross energy, digestible energy and metabolizable energy intake, heat production and milk energy output. However, cow genotype had no significant effects on energy utilization efficiency or CH4 parameters. Furthermore, the present study yielded a value for gross energy lost as CH4 (5.6 %) on fresh grass-based diets that is lower than the widely accepted value of 6.5 %. The present findings indicate reducing concentrate CP content from 18.1 to 14.1 % may not be a successful approach to alleviate CH4 emissions from lactating dairy cows offered good quality fresh grass, however grazing cows could be offered a low CP concentrate without compromising energy utilization efficiency. Further research is needed to investigate whether larger differences in dietary CP content may yield positive results
Management of Spinal Deformities and Evidence of Treatment Effectiveness
Introduction:The review evaluates the up-to-date evidence for the treatment of spinal deformities, including scoliosis and hyperkyphosis in adolescents and adults.Material and Methods:The PubMed database was searched for review articles, prospective controlled trials and randomized controlled trials related to the treatment of spinal deformities. Articles on syndromic scoliosis were excluded and so were the articles on hyperkyphosis of the spine with causes other than Scheuermann’s disease and osteoporosis. Articles on conservative and surgical treatments of idiopathic scoliosis, adult scoliosis and hyperkyphosis were also included. For retrospective papers, only studies with a follow up period exceeding 10 years were included.Results:The review showed that early-onset idiopathic scoliosis has a worse outcome than late-onset idiopathic scoliosis, which is rather benign. Patients with AIS function well as adults; they have no more health problems when compared to patients without scoliosis, other than a slight increase in back pain and aesthetic concern. Conservative treatment of adolescent idiopathic scoliosis (AIS) using physiotherapeutic scoliosis-specific exercises (PSSE), specifically PSSR and rigid bracing was supported by level I evidence. Yet to date, there is no high quality evidence (RCT`s) demonstrating that surgical treatment is superior to conservative treatment for the management of AIS. For adult scoliosis, there are only a few studies on the effectiveness of PSSEs and a conclusion cannot as yet be drawn.For hyperkyphosis, there is no high-quality evidence for physiotherapy, bracing or surgery for the treatment of adolescents and adults. However, bracing has been found to reduce thoracic hyperkyphosis, ranging from 55 to 80° in adolescents. In patients over the age of 60, bracing improves the balance score, and reduces spinal deformity and pain. Surgery is indicated in adolescents and adults in the presence of progression of kyphosis, refractory pain and loss of balance.Discussion:The available evidence reviewed has suggested that different approaches are needed towards the management of different spinal deformities. Specific exercises should be prescribed in children and adolescents with a Cobb angle in excess of 15°. In progressive curves, they should be used in conjunction with bracing. Clarity regarding differences and similarities is given as to what makes PSSE and PSSR specific exercises. As AIS is relatively benign in nature, conservative treatment should be tried when the curve is at a surgical threshold, before surgery is considered. Similarly, bracing and exercises should be prescribed for patients with hyperkyphosis, particularly when the lumbar spine is afflicted. Surgery should be considered only when the symptoms cannot be managed conservatively.Conclusion:There is at present high quality evidence in support of the conservative treatment of AIS. The current evidence supports the use of PSSE, especially those using PSSR, together with bracing in the treatment of AIS. In view of the lack of medical consequences in adults with AIS, conservative treatment should be considered for curves exceeding the formerly assumed range of conservative indications.There is, however a lack of evidence in support of any treatment of choice for hyperkyphosis in adolescents and spinal deformities in adults. Yet, conservative treatment should be considered first. Yet to date, there is no high quality evidence (RCT`s) demonstrating that surgical treatment is superior to conservative treatment for the management of AIS and hyperkyphosis. Additionally, surgery needs to be considered with caution, as it is associated with a number of long-term complications.</jats:sec
Structural Racism and Severe Maternal Morbidity in New York State
ABSTRACT
Objective: We examined the association between county-level structural racism indicators and the odds of severe maternal morbidity (SMM) in New York State.
Design: We merged individual-level hospitalization data from the New York State Department of Health Statewide Planning and Research Cooperative System (SPARCS) with county-level data from the American Community Survey and the Vera Institute of Justice from 2011 to 2013 (n = 244 854). Structural racism in each county included in our sample was constructed as the racial inequity (ratio of black to white population) in female educational attainment, female employment, and incarceration.ReSulT S: Multilevel logistic regression analysis estimated the association between each of these structural racism indicators and SMM, accounting for individual- and hospital-level characteristics and clustering in facilities. In the models adjusted for individual- and hospital-level factors, county-level racial inequity in female educational attainment was associated with small but statistically significant higher odds of SMM (odds ratio [OR] = 1.17, 95% confidence interval [CI] = 1.47, 1.85). County-level structural racism indicators of female employment inequity and incarceration inequity were not statistically significant. Interaction terms examining potential effect measure modification by race with each structural racism indicator also indicated no statistical difference.
Conclusions: Studies of maternal disparities should consider multiple dimensions of structural racism as a contributing cause to SMM and as an additional area for potential intervention
Prevalence of and Risk Factors for Adolescent Obesity in Tennessee Using the 2010 Youth Risk Behavior Survey (YRBS) Data: An Analysis Using Weighted Hierarchical Logistic Regression
Background: The rate of adolescent overweight and obesity has more than quadrupled over the past few decades, and has become a major public health problem [1]. In 2011, 55% of 12-19 year olds in the United States (U.S.) were overweight or obese [2]. Adolescence is a pivotal time in which many health risk behaviors such as tobacco, alcohol, and drug use are initiated. Such health risk behaviors have been significantly associated with overweight and obesity among adolescents.
Objective: The purpose of this study is to evaluate the relationship between obesity and the health risk behaviors most commonly associated with premature morbidity and mortality among adolescents with a novel micro area estimate approach that uses weighted hierarchical logistic regression to nest individuals in classes, classes in schools, and schools in districts.
Methods: This study is a secondary analysis of a state-wide representative sample of middle school students that participated in the 2010 Tennessee Middle School Youth Risk Behavior Survey (YRBS). Data was collected from 119 (85.6%) of Tennessee’s local education agencies (LEAs), 456 (95.2%) schools, and 64,790 of 78,441 (82.6%) students. The outcome variable was adolescent obesity (≥ 95th BMI percentile). Explanatory variables were divided into four levels [1] district level: use seatbelt/helmet, asked to show ID for tobacco purchase; [2] school level: ever tried smoking, received HIV education in school; [3] class level: average number of days smoked, having ever exercised to lose weight; [4] individual level: having ever been in fight, early onset of substance use, physical activity, and thought about, planed, or attempted suicide. Weighted hierarchical logistic regression analysis was performed to assess the association between risk factors or protective factors and obesity using effect size (ES) and odds ratio (OR) estimates.
Results: The study sample included 64,790 middle school students in the state of Tennessee with a mean age of 12.8 years, of which (49.42%) were females and (50.58%) were males. Nearly one-fourth of the students had a BMI at or above the 95th percentile (22.30%). Weighted hierarchical logistic regression analysis shows that seatbelt and helmet use [ES: -2.161 OR: 0.020, 95% CI: (0.006, 0.070)], and weight misperception [ES: 1.256 OR: 9.720, 95% CI: (9.216, 10.251)], having ever exercised to lose weight [ES: -0.340 OR: 0.540, 95% CI: (0.446, 0.654)], having ever tried smoking [ES: 0.705 OR: 3.581, 95% CI: (2.637, 4.863)] and gender (male vs female) [ES: 0.327 OR: 1.810, 95% CI: (1.740, 1.880)] were strongly associated with adolescent obesity. Results from this study also showed that Black, Hispanic or Latino adolescents were more likely to be obese than Whites, Indian, and Asian adolescent [ES: 0.129 OR: 1.260, 95% CI: (1.200, 1.330)], students with grades of mostly C, D and F were more likely to be obese than those with grades of mostly A and B [ES: 0.189 OR: 1.409, 95% CI: (1.303, 1.523)], and that students having an eating disorder [ES: 0.251 OR: 1.576, 95% CI: (1.508, 1.648)] and/or engagement in sports teams [ES: -0.197 OR: 0.700, 95% CI: (0.674, 0.728)] had small or medium ES association with adolescent obesity.
Conclusion:This study uses small area estimates in weighted hierarchical logistic regression models to describe the prevalence and distribution of health risk behaviors associated with adolescent obesity among middle school student subpopulations in Tennessee. The value of small area estimates has been demonstrated previously in a variety of other contexts, and again here offers important insights for intervention design and resource allocation at different micro-levels within small and large areas (i.e., district, school, and class). This work adds to the growing body of research that supports community-driven school-based lifestyle interventions targeting early-onset chronic disease and, more specifically, enhances the geographic resolution with which adolescent obesity can be addressed in middle school populations across Tennessee
In Vivo Protection with Human Monoclonal Antibody S315 following Challenge with Diphtheria Toxin
Background: Morbidity and mortality from Corynebacterium diphtheriae is reduced by prompt administration of equine-derived diphtheria anti-toxin (DAT), which is in short supply worldwide. MassBiologics has developed a human monoclonal antibody (S315) to diphtheria toxin to provide a safer alternative to DAT and address critical supply issues. S315 prevents toxin binding to its putative host receptor and S315 pre-mixed with toxin increased survival in a guinea pig model of intoxication. To further evaluate the ability of S315 to provide in vivo protection, we established a post-exposure treatment model.
Methods: Female Hartley guinea pigs (300-350g) were challenged subcutaneously with diphtheria toxin (0.03 to 0.09 Lf, limit of flocculation) to identify the minimum lethal dose. To evaluate anti-toxin efficacy, DAT or S315 was administered five hours post-toxin challenge and animals monitored for 30 days for signs of illness (lethargy, dehydration, weak limbs). Serum anti-diphtheria toxin antibodies were measured by ELISA and Vero cell toxin neutralization assays.
Results: The minimum lethal toxin dose was 0.09 Lf. To determine the protective dose of DAT, 0.2 IU, 1.0 IU or 5.0 IU was administered intravenously post-toxin challenge (n=4/cohort). All 0.2 IU or 1.0 IU DAT-treated animals died, while one animal treated with 5.0 IU survived. DAT was subsequently evaluated at 5.0 IU, 10 IU, and 20 IU and compared to a cohort receiving 3.5 mg of S315. All untreated animals died within 72 hours and all antibody-treated animals survived. Dehydration was observed more frequently in the 5 IU and 10 IU DAT cohorts compared to the 20 IU and S315 cohorts.
Conclusions: Treatment with S315 after diphtheria toxin exposure is protective; further studies will define a minimum effective dose of S315. This model mimics the route and timing of anti-toxin treatment in humans and provides a rigorous preclinical evaluation of a human antibody replacement for equine DAT
The evolution of TEP1, an exceptionally polymorphic immunity gene in Anopheles gambiae
<p>Abstract</p> <p>Background</p> <p>Host-parasite coevolution can result in balancing selection, which maintains genetic variation in the susceptibility of hosts to parasites. It has been suggested that variation in a thioester-containing protein called <it>TEP1 </it>(AGAP010815) may alter the ability of <it>Anopheles </it>mosquitoes to transmit <it>Plasmodium </it>parasites, and high divergence between alleles of this gene suggests the possible action of long-term balancing selection. We studied whether <it>TEP1 </it>is a case of an ancient balanced polymorphism in an animal immune system.</p> <p>Results</p> <p>We found evidence that the high divergence between <it>TEP1 </it>alleles is the product of genetic exchange between <it>TEP1 </it>and other TEP loci, i.e. gene conversion. Additionally, some <it>TEP1 </it>alleles showed unexpectedly low variability.</p> <p>Conclusion</p> <p>The <it>TEP1 </it>gene appears to be a chimera produced from at least two other <it>TEP </it>loci, and the divergence between <it>TEP1 </it>alleles is probably not caused by long-term balancing selection, but is instead due to two independent gene conversion events from one of these other genes. Nevertheless, <it>TEP1 </it>still shows evidence of natural selection, in particular there appears to have been recent changes in the frequency of alleles that has diminished polymorphism within each allelic class. Although the selective force driving this dynamic was not identified, given that susceptibility to <it>Plasmodium </it>parasites is known to be associated with allelic variation in <it>TEP1</it>, these changes in allele frequencies could alter the vectoring capacity of populations.</p
Stage-specific transcriptomes of the Mussel Mytilus coruscus reveals the developmental Program for the Planktonic to Benthic Transition
Many marine invertebrate larvae undergo complex morphological and physiological changes during the planktonic—benthic transition (a.k.a. metamorphosis). In this study, transcriptome analysis of different developmental stages was used to uncover the molecular mechanisms underpinning larval settlement and metamorphosis of the mussel, Mytilus coruscus. Analysis of highly upregulated differentially expressed genes (DEGs) at the pediveliger stage revealed enrichment of immune-related genes. The results may indicate that larvae co-opt molecules of the immune system to sense and respond to external chemical cues and neuroendocrine signaling pathways forecast and trigger the response. The upregulation of adhesive protein genes linked to byssal thread secretion indicates the anchoring capacity required for larval settlement arises prior to metamorphosis. The results of gene expression support a role for the immune and neuroendocrine systems in mussel metamorphosis and provide the basis for future studies to disentangle gene networks and the biology of this important lifecycle transformation.info:eu-repo/semantics/publishedVersio
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