192 research outputs found
Immunization with one Theileria parva strain results in similar level of CTL strain-specificity and protection compared to immunization with the three-component Muguga cocktail in MHC-matched animals
Abstract Background The tick-borne protozoan parasite Theileria parva causes a usually fatal cattle disease known as East Coast fever in sub-Saharan Africa, with devastating consequences for poor small-holder farmers. Immunity to T. parva, believed to be mediated by a cytotoxic T lymphocyte (CTL) response, is induced following natural infection and after vaccination with a live vaccine, known as the Infection and Treatment Method (ITM). The most commonly used version of ITM is a combination of parasites derived from three isolates (Muguga, Kiambu 5 and Serengeti-transformed), known as the “Muguga cocktail”. The use of a vaccine comprising several strains is believed to be required to induce a broad immune response effective against field challenge. In this study we investigated whether immunization with the Muguga cocktail induces a broader CTL response than immunization with a single strain (Muguga). Results Four MHC haplotype-matched pairs of cattle were immunized with either the trivalent Muguga cocktail or the single Muguga strain. CTL specificity was assessed on a panel of five different strains, and clonal responses to these strains were also assessed in one of the MHC-matched pairs. We did not find evidence for a broader CTL response in animals immunized with the Muguga cocktail compared to those immunized with the Muguga strain alone, in either the bulk or clonal CTL analyses. This was supported by an in vivo trial in which all vaccinated animals survived challenge with a lethal dose of the Muguga cocktail vaccine stabilate. Conclusion We did not observe any substantial differences in the immunity generated from animals immunized with either Muguga alone or the Muguga cocktail in the animals tested here, corroborating earlier results showing limited antigenic diversity in the Muguga cocktail. These results may warrant further field studies using single T. parva strains as future vaccine candidates
Discoidin domain receptor-1 regulates calcific extracellular vesicle release in vascular smooth muscle cell fibrocalcific response via transforming growth factor-β signaling
Objective - Collagen accumulation and calcification are major determinants of atherosclerotic plaque stability. Extracellular vesicle (EV)-derived microcalcifications in the collagen-poor fibrous cap may promote plaque rupture. In this study, we hypothesize that the collagen receptor discoidin domain receptor-1 (DDR-1) regulates collagen deposition and release of calcifying EVs by vascular smooth muscle cells (SMCs) through the transforming growth factor-β (TGF-β) pathway. Approach and Results - SMCs from the carotid arteries of DDR-1-/- mice and wild-type littermates (n=5-10 per group) were cultured in normal or calcifying media. At days 14 and 21, SMCs were harvested and EVs isolated for analysis. Compared with wild-type, DDR-1-/- SMCs exhibited a 4-fold increase in EV release (P<0.001) with concomitantly elevated alkaline phosphatase activity (P<0.0001) as a hallmark of EV calcifying potential. The DDR-1-/- phenotype was characterized by increased mineralization (Alizarin Red S and Osteosense, P<0.001 and P=0.002, respectively) and amorphous collagen deposition (P<0.001). We further identified a novel link between DDR-1 and the TGF-β pathway previously implicated in both fibrotic and calcific responses. An increase in TGF-β1 release by DDR-1-/- SMCs in calcifying media (P<0.001) stimulated p38 phosphorylation (P=0.02) and suppressed activation of Smad3. Inhibition of either TGF-β receptor-I or phospho-p38 reversed the fibrocalcific DDR-1-/- phenotype, corroborating a causal relationship between DDR-1 and TGF-β in EV-mediated vascular calcification. Conclusions - DDR-1 interacts with the TGF-β pathway to restrict calcifying EV-mediated mineralization and fibrosis by SMCs. We therefore establish a novel mechanism of cell-matrix homeostasis in atherosclerotic plaque formation
Exposure to phthalates among premenstrual girls from rural and urban Gharbiah, Egypt: A pilot exposure assessment study
<p>Abstract</p> <p>Background</p> <p>Phthalates have been identified as endocrine active compounds associated with developmental and reproductive toxicity. The exposure to phthalates in premenstrual Egyptian females remains unknown. The objective of this study was to characterize phthalate exposure of a potentially vulnerable population of premenstrual girls from urban and rural Egypt.</p> <p>Materials and methods</p> <p>We collected one spot urine sample from 60 10-13 year old females, 30 from rural Egypt, and 30 from urban Egypt from July to October 2009. Samples were analyzed for 11 phthalate metabolites. Additionally, we collected anthropometrics as well as questionnaire data concerning food storage behaviors, cooking practices, and cosmetic use. Phthalate metabolite concentrations were compared between urban and rural Egyptians as well as to age and gender matched Americans.</p> <p>Results</p> <p>Monoethyl phthalate (MEP), was detected at the highest concentration in urine of Egyptian girls (median: 43.2 ng/mL in rural, 98.8 ng/mL in urban). Concentrations of urinary metabolites of di-(2-ethylhexyl) phthalate and dibutyl phthalate were comparable between Egyptians and age matched US girls. Storage of food in plastic containers was a statistically significant predictor of urinary mono-isobutyl phthalate (MiBP) concentrations when comparing covariate adjusted means.</p> <p>Conclusions</p> <p>Urinary concentrations of phthalate metabolites were similar in Egyptian and US populations, suggesting that phthalate exposure also occurs in developing nations. Dietary intake is likely an important route of exposure to phthalates in both urban and rural populations.</p
DNA Methylation Analysis Identifies Loci for Blood Pressure Regulation
Genome-wide association studies have identified hundreds of genetic variants associated with blood pressure (BP), but sequence variation accounts for a small fraction of the phenotypic variance. Epigenetic changes may alter the expression of genes involved in BP regulation and explain part of the missing heritability. We therefore conducted a two-stage meta-analysis of the cross-sectional associations of systolic and diastolic BP with blood-derived genome-wide DNA methylation measured on the Infinium HumanMethylation450 BeadChip in 17,010 individuals of European, African American, and Hispanic ancestry. Of 31 discovery-stage cytosine-phosphate-guanine (CpG) dinucleotides, 13 replicated after Bonferroni correction (discovery: N = 9,828, p < 1.0 × 10−7; replication: N = 7,182, p < 1.6 × 10−3). The replicated methylation sites are heritable (h2 > 30%) and independent of known BP genetic variants, explaining an additional 1.4% and 2.0% of the interindividual variation in systolic and diastolic BP, respectively. Bidirectional Mendelian randomization among up to 4,513 individuals of European ancestry from 4 cohorts suggested that methylation at cg08035323 (TAF1B-YWHAQ) influences BP, while BP influences methylation at cg00533891 (ZMIZ1), cg00574958 (CPT1A), and cg02711608 (SLC1A5). Gene expression analyses further identified six genes (TSPAN2, SLC7A11, UNC93B1, CPT1A, PTMS, and LPCAT3) with evidence of triangular associations between methylation, gene expression, and BP. Additional integrative Mendelian randomization analyses of gene expression and DNA methylation suggested that the expression of TSPAN2 is a putative mediator of association between DNA methylation at cg23999170 and BP. These findings suggest that heritable DNA methylation plays a role in regulating BP independently of previously known genetic variants
Correlates of women's cancer screening and contraceptive knowledge among female emergency department patients
<p>Abstract</p> <p>Background</p> <p>Lack of knowledge regarding preventive health services for women might impede campaigns to expand these services in the emergency department setting. For 18–55-year-old English-speaking women visiting an urban emergency department, we aimed to: (1) Ascertain their knowledge regarding the applicability, purpose, and recommended intervals of three women's cancer screening and three contraceptive methods; and (2) Determine if patient age, race/ethnicity, medical insurance status, and current or recent usage of these methods are associated with greater or lesser knowledge about them.</p> <p>Methods</p> <p>Emergency department-based survey on recent or current usage and knowledge about Pap smears, breast self-examinations, mammograms, condoms, birth control, and emergency contraception. Analyses included calculation of summary statistics and creation of multivariable logistic regression models.</p> <p>Results</p> <p>Of 1,100 patients eligible for the study, 69.9% agreed to participate. Most of the participants were < age 35, white, single (never married and no partner), Catholic, and had private medical insurance. Participant's recent or current usage of a particular cancer screening or contraceptive method varied by type of method: Pap smear within the past year (69.1%), breast self-exam within the past month (45.5%), mammogram within the past year (65.7% for women age 45–55), condom usage during every episode of sexual intercourse (15.4%), current usage of birth control pills (17.8%), and ever use of emergency contraception (9.3%). The participants correctly answered 87.9% of all survey questions about condoms, 82.5% about birth control pills, 78.5% about breast self-exams, 52.9% about Pap smears, 35.4% about mammograms, and 25.0% about emergency contraception. In multivariable logistic regression models, survey participants who had private medical insurance and those who recently or currently used a given screening or contraceptive method had a greater odds of correctly answering all questions about each cancer screening or contraceptive method.</p> <p>Conclusion</p> <p>Although these female ED patients demonstrated strong knowledge on some women's cancer screening and contraceptive methods, there were several areas of knowledge deficit. Women without private medical insurance and those who have not used a particular cancer screening or contraceptive method demonstrated less knowledge. Reduced knowledge about women's cancer screening and contraceptive methods should be considered during clinical encounters and when instituting or evaluating emergency department-based initiatives that assess the need for these methods.</p
Synonymous Codon Ordering: A Subtle but Prevalent Strategy of Bacteria to Improve Translational Efficiency
Background: In yeast coding sequences, once a particular codon has been used, subsequent occurrence of the same amino acid tends to use codons sharing the same tRNA. Such a phenomenon of co-tRNA codons pairing bias (CTCPB) is also found in some other eukaryotes but it is not known whether it occurs in prokaryotes. Methodology/Principal Findings: In this study, we focused on a total of 773 bacterial genomes to investigate their synonymous codon pairing preferences. After calculating the actual frequencies of synonymous codon pairs and comparing them with their expected values, we detected an obvious pairing bias towards identical codon pairs. This seems consistent with the previously reported CTCPB phenomenon, since identical codons are certainly read by the same tRNA. However, among co-tRNA but non-identical codon pairs, only 22 were often found overrepresented, suggesting that many co-tRNA codons actually do not preferentially pair together in prokaryotes. Therefore, the previously reported co-tRNA codons pairing rule needs to be more rigorously defined. The affinity differences between a tRNA anticodon and its readable codons should be taken into account. Moreover, both within-gene-shuffling tests and phylogenetic analyses support the idea that translational selection played an important role in shaping the observed synonymous codon pairing pattern in prokaryotes. Conclusions: Overall, a high level of synonymous codon pairing bias was detected in 73 % investigated bacterial species
CNS activity of Pokeweed Anti-viral Protein (PAP) in mice infected with Lymphocytic Choriomeningitis Virus (LCMV)
BACKGROUND: Others and we have previously described the potent in vivo and in vitro activity of the broad-spectrum antiviral agent PAP (Pokeweed antiviral protein) against a wide range of viruses. The purpose of the present study was to further elucidate the anti-viral spectrum of PAP by examining its effects on the survival of mice challenged with lymphocytic choriomeningitis virus (LCMV). METHODS: We examined the therapeutic effect of PAP in CBA mice inoculated with intracerebral injections of the WE54 strain of LCMV at a 1000 PFU dose level that is lethal to 100% of mice within 7–9 days. Mice were treated either with vehicle or PAP administered intraperitoneally 24 hours prior to, 1 hour prior to and 24 hours, 48 hours 72 hours and 96 hours after virus inoculation. RESULTS: PAP exhibits significant in vivo anti- LCMV activity in mice challenged intracerebrally with an otherwise invariably fatal dose of LCMV. At non-toxic dose levels, PAP significantly prolonged survival in the absence of the majority of disease-associated symptoms. The median survival time of PAP-treated mice was >21 days as opposed to 7 days median survival for the control (p = 0.0069). CONCLUSION: Our results presented herein provide unprecedented experimental evidence that PAP exhibits antiviral activity in the CNS of LCMV-infected mice
Genome-Wide Detection of Allele Specific Copy Number Variation Associated with Insulin Resistance in African Americans from the HyperGEN Study
African Americans have been understudied in genome wide association studies of diabetes and related traits. In the current study, we examined the joint association of single nucleotide polymorphisms (SNPs) and copy number variants (CNVs) with fasting insulin and an index of insulin resistance (HOMA-IR) in the HyperGEN study, a family based study with proband ascertainment for hypertension. This analysis is restricted to 1,040 African Americans without diabetes. We generated allele specific CNV genotypes at 872,243 autosomal loci using Birdsuite, a freely available multi-stage program. Joint tests of association for SNPs and CNVs were performed using linear mixed models adjusting for covariates and familial relationships. Our results highlight SNPs associated with fasting insulin and HOMA-IR (rs6576507 and rs8026527, 3.7*10−7≤P≤1.1*10−5) near ATPase, class V, type 10A (ATP10A), and the L Type voltage dependent calcium channel (CACNA1D, rs1401492, P≤5.2*10−6). ATP10A belongs to a family of aminophospholipid-transporting ATPases and has been associated with type 2 diabetes in mice. CACNA1D has been linked to pancreatic beta cell generation in mice. The two most significant copy variable markers (rs10277702 and rs361367; P<2.0*10−4) were in the beta variable region of the T-cell receptor gene (TCRVB). Human and mouse TCR has been shown to mimic insulin and its receptor and could contribute to insulin resistance. Our findings differ from genome wide association studies of fasting insulin and other diabetes related traits in European populations, highlighting the continued need to investigate unique genetic influences for understudied populations such as African Americans
A novel emergency department based prevention intervention program for people living with HIV: evaluation of early experiences
<p>Abstract</p> <p>Background</p> <p>HIV prevention is increasingly focused on people living with HIV (PLWH) and the role of healthcare settings in prevention. Emergency Departments (EDs) frequently care for PLWH, but do not typically endorse a prevention mission. We conducted a pilot exploratory evaluation of the first reported ED program to address the prevention needs of PLWH.</p> <p>Methods</p> <p>This retrospective observational cohort evaluation reviewed program records to describe the first six months of participants and programmatic operation. Trained counselors provided a risk assessment and counseling intervention combined with three linkage interventions: i) linkage to health care, ii) linkage to case management, and iii) linkage to partner counseling and referral.</p> <p>Results</p> <p>Of 81 self-identified PLWH who were approached, 55 initially agreed to participate. Of those completing risk assessment, 17/53 (32%, 95 CI 20% to 46%) reported unprotected anal/vaginal intercourse or needle sharing in the past six months with a partner presumed to be HIV negative. Counseling was provided to 52/53 (98%). For those requesting services, 11/15 (73%) were linked to healthcare, 4/23 (17%) were coordinated with case management, and 1/4 (25%) completed partner counseling and referral.</p> <p>Conclusion</p> <p>Given base resources of trained counselors, it was feasible to implement a program to address the prevention needs for persons living with HIV in an urban ED. ED patients with HIV often have unmet needs which might be addressed by improved linkage with existing community resources. Healthcare and prevention barriers for PLWH may be attenuated if EDs were to incorporate CDC recommended prevention measures for healthcare providers.</p
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