689 research outputs found
Investing in longitudinal studies of primary healthcare: what can we learn about service performance, sustainability and quality?
Antibodies against Merozoite Surface Protein (Msp)-119 Are a Major Component of the Invasion-Inhibitory Response in Individuals Immune to Malaria
Antibodies that bind to antigens expressed on the merozoite form of the malaria parasite can inhibit parasite growth by preventing merozoite invasion of red blood cells. Inhibitory antibodies are found in the sera of malaria-immune individuals, however, the specificity of those that are important to this process is not known. In this paper, we have used allelic replacement to construct a Plasmodium falciparum parasite line that expresses the complete COOH-terminal fragment of merozoite surface protein (MSP)-119 from the divergent rodent malaria P. chabaudi. By comparing this transfected line with parental parasites that differ only in MSP-119, we show that antibodies specific for this domain are a major component of the inhibitory response in P. falciparumâimmune humans and P. chabaudiâimmune mice. In some individual human sera, MSP-119 antibodies dominated the inhibitory activity. The finding that antibodies to a small region of a single protein play a major role in this process has important implications for malaria immunity and is strongly supportive of further understanding and development of MSP-119âbased vaccines
β1 integrin mediates an alternative survival pathway in breast cancer cells resistant to lapatinib
Abstract Introduction The overexpression of human epidermal growth factor receptor (HER)-2 in 20% of human breast cancers and its association with aggressive growth has led to widespread use of HER2-targeted therapies, such as trastuzumab (T) and lapatinib (L). Despite the success of these drugs, their efficacy is limited in patients whose tumors demonstrate de novo or acquired resistance to treatment. The β1 integrin resides on the membrane of the breast cancer cell, activating several elements of breast tumor progression including proliferation and survival. Methods We developed a panel of HER2-overexpressing cell lines resistant to L, T, and the potent LT combination through long-term exposure and validated these models in 3D culture. Parental and L/T/LT-resistant cells were subject to HER2 and β1 integrin inhibitors in 3D and monitored for 12 days, followed by quantification of colony number. Parallel experiments were conducted where cells were either stained for Ki-67 and Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) or harvested for protein and analyzed by immunoblot. Results were subjected to statistical testing using analysis of variance and linear contrasts, followed by adjustment with the Sidak method. Results Using multiple cell lines including BT474 and HCC1954, we reveal that in L and LT resistance, where phosphorylation of EGFR/HER1, HER2, and HER3 are strongly inhibited, kinases downstream of β1 integrin--including focal adhesion kinase (FAK) and Src--are up-regulated. Blockade of β1 by the antibody AIIB2 abrogates this up-regulation and functionally achieves significant growth inhibition of L and LT resistant cells in 3D, without dramatically affecting the parental cells. SiRNA against β1 as well as pharmacologic inhibition of FAK achieve the same growth inhibitory effect. In contrast, trastuzumab-resistant cells, which retain high levels of phosphorylated EGFR/HER1, HER2, and HER3, are only modestly growth-inhibited by AIIB2. Conclusions Our data suggest that HER2 activity, which is suppressed in resistance involving L but not T alone, dictates whether β1 mediates an alternative pathway driving resistance. Our findings justify clinical studies investigating the inhibition of β1 or its downstream signaling moieties as strategies to overcome acquired L and LT resistance
Variability of polycyclic aromatic hydrocarbons and their oxidative derivatives in wintertime Beijing, China
Ambient particulate matter (PM) can contain a mix of different toxic species derived from a wide variety of sources. This study quantifies the diurnal variation and nocturnal abundance of 16 polycyclic aromatic hydrocarbons (PAHs), 10 oxygenated PAHs (OPAHs) and 9 nitrated PAHs (NPAHs) in ambient PM in central Beijing during winter. Target compounds were identified and quantified using gas chromatography-time-of-flight mass spectrometry (GC-Q-ToF-MS). The total concentration of PAHs varied between 18 and 297 ngm-3 over 3 h daytime filter samples and from 23 to 165 ngm-3 in 15 h night-time samples. The total concentrations of PAHs over 24 h varied between 37 and 180 ngm-3 (mean: 97Âą43 ngm-3). The total daytime concentrations during high particulate loading conditions for PAHs, OPAHs and NPAHs were 224, 54 and 2.3 ngm-3, respectively. The most abundant PAHs were fluoranthene (33 ngm-3), chrysene (27 ngm-3), pyrene (27 ngm-3), benzo[a]pyrene (27 ngm-3), benzo[b]fluoranthene (25 ngm-3), benzo[a]anthracene (20 ngm-3) and phenanthrene (18 ngm-3). The most abundant OPAHs were 9,10-anthraquinone (18 ngm-3), 1,8-naphthalic anhydride (14 ngm-3) and 9-fluorenone (12 ngm-3), and the three most abundant NPAHs were 9-nitroanthracene (0.84 ngm-3), 3-nitrofluoranthene (0.78 ngm-3) and 3-nitrodibenzofuran (0.45 ngm-3). ÎŁ PAHs and ÎŁ OPAHs showed a strong positive correlation with the gas-phase abundance of NO, CO, SO2 and HONO, indicating that PAHs and OPAHs can be associated with both local and regional emissions. Diagnostic ratios suggested emissions from traffic road and coal combustion were the predominant sources of PAHs in Beijing and also revealed the main source of NPAHs to be secondary photochemical formation rather than primary emissions. PM2.5 and NPAHs showed a strong correlation with gas-phase HONO. 9- Nitroanthracene appeared to undergo a photodegradation during the daytime and showed a strong positive correlation with ambient HONO (R D 0:90, P <0:001). The lifetime excess lung cancer risk for those species that have available toxicological data (16 PAHs, 1 OPAH and 6 NPAHs) was calculated to be in the range 10-5 to 10-3 (risk per million people ranges from 26 to 2053 cases per year)
Disparities in Healthy Food Zoning, Farmers\u27 Market Availability, and Fruit and Vegetable Consumption Among North Carolina Residents
Background: Context and purpose of the study. To examine (1) associations between county-level zoning to support farmers\u27 market placement and county-level farmers\u27 market availability, rural/urban designation, percent African American residents, and percent of residents living below poverty and (2) individual-level associations between zoning to support farmers\u27 markets; fruit and vegetable consumption and body mass index (BMI) among a random sample of residents of six North Carolina (NC) counties. Methods: Zoning ordinances were scored to indicate supportiveness for healthy food outlets. Number of farmers\u27 markets (per capita) was obtained from the NC-Community Transformation Grant Project Fruit and Vegetable Outlet Inventory (2013). County-level census data on rural/urban status, percent African American, and percent poverty were obtained. For data on farmers\u27 market shopping, fruit and vegetable consumption, and BMI, trained interviewers conducted a random digit dial telephone survey of residents of six NC counties (3 urban and 3 rural). Pearson correlation coefficients and multilevel linear regression models were used to examine county-level and individual-level associations between zoning supportiveness, farmers\u27 market availability, and fruit and vegetable consumption and BMI. Results: At the county-level, healthier food zoning was greater in more urban areas and areas with less poverty. At the individual-level, self-reported fruit and vegetable consumption was associated with healthier food zoning. Conclusions: Disparities in zoning to promote healthy eating should be further examined, and future studies should assess whether amending zoning ordinances will lead to greater availability of healthy foods and changes in dietary behavior and health outcomes
Family Ties to Health Program: A Randomized Intervention to Improve Vegetable Intake in Children
Evaluate a home-based intervention targeted toward parents to improve vegetable intake in preschool-aged children
Farmers\u27 market use is associated with fruit and vegetable consumption in diverse southern rural communities
Background
While farmersâ markets are a potential strategy to increase access to fruits and vegetables in rural areas, more information is needed regarding use of farmersâ markets among rural residents. Thus, this studyâs purpose was to examine (1) socio-demographic characteristics of participants; (2) barriers and facilitators to farmersâ market shopping in southern rural communities; and (3) associations between farmersâ market use with fruit and vegetable consumption and body mass index (BMI). Methods
Cross-sectional surveys were conducted with a purposive sample of farmersâ market customers and a representative sample of primary household food shoppers in eastern North Carolina (NC) and the Appalachian region of Kentucky (KY). Customers were interviewed using an intercept survey instrument at farmersâ markets. Representative samples of primary food shoppers were identified via random digit dial (RDD) cellular phone and landline methods in counties that had at least one farmersâ market. All questionnaires assessed socio-demographic characteristics, food shopping patterns, barriers to and facilitators of farmersâ market shopping, fruit and vegetable consumption and self-reported height and weight. The main outcome measures were fruit and vegetable consumption and BMI. Descriptive statistics were used to examine socio-demographic characteristics, food shopping patterns, and barriers and facilitators to farmersâ market shopping. Linear regression analyses were used to examine associations between farmersâ market use with fruit and vegetable consumption and BMI, controlling for age, race, education, and gender. Results
Among farmersâ market customers, 44% and 55% (NC and KY customers, respectively) reported shopping at a farmersâ market at least weekly, compared to 16% and 18% of NC and KY RDD respondents. Frequently reported barriers to farmersâ market shopping were market days and hours, âonly come when I need somethingâ, extreme weather, and market location. Among the KY farmersâ market customers and NC and KY RDD respondents, fruit and vegetable consumption was positively associated with use of farmersâ markets. There were no associations between use of farmersâ markets and BMI. Conclusions
Fruit and vegetable consumption was associated with farmersâ market shopping. Thus, farmersâ markets may be a viable method to increase population-level produce consumption
FarmersĂ¢âââ⢠market use is associated with fruit and vegetable consumption in diverse southern rural communities
Background
While farmersââŹâ˘ markets are a potential strategy to increase access to fruits and vegetables in rural areas, more information is needed regarding use of farmersââŹâ˘ markets among rural residents. Thus, this studyââŹâ˘s purpose was to examine (1) socio-demographic characteristics of participants; (2) barriers and facilitators to farmersââŹâ˘ market shopping in southern rural communities; and (3) associations between farmersââŹâ˘ market use with fruit and vegetable consumption and body mass index (BMI).
Methods
Cross-sectional surveys were conducted with a purposive sample of farmersââŹâ˘ market customers and a representative sample of primary household food shoppers in eastern North Carolina (NC) and the Appalachian region of Kentucky (KY). Customers were interviewed using an intercept survey instrument at farmersââŹâ˘ markets. Representative samples of primary food shoppers were identified via random digit dial (RDD) cellular phone and landline methods in counties that had at least one farmersââŹâ˘ market. All questionnaires assessed socio-demographic characteristics, food shopping patterns, barriers to and facilitators of farmersââŹâ˘ market shopping, fruit and vegetable consumption and self-reported height and weight. The main outcome measures were fruit and vegetable consumption and BMI. Descriptive statistics were used to examine socio-demographic characteristics, food shopping patterns, and barriers and facilitators to farmersââŹâ˘ market shopping. Linear regression analyses were used to examine associations between farmersââŹâ˘ market use with fruit and vegetable consumption and BMI, controlling for age, race, education, and gender.
Results
Among farmersââŹâ˘ market customers, 44% and 55% (NC and KY customers, respectively) reported shopping at a farmersââŹâ˘ market at least weekly, compared to 16% and 18% of NC and KY RDD respondents. Frequently reported barriers to farmersââŹâ˘ market shopping were market days and hours, ââŹĹonly come when I need somethingââŹďż˝, extreme weather, and market location. Among the KY farmersââŹâ˘ market customers and NC and KY RDD respondents, fruit and vegetable consumption was positively associated with use of farmersââŹâ˘ markets. There were no associations between use of farmersââŹâ˘ markets and BMI.
Conclusions
Fruit and vegetable consumption was associated with farmersââŹâ˘ market shopping. Thus, farmersââŹâ˘ markets may be a viable method to increase population-level produce consumption
An ammonia spectral map of the L1495-B218 filaments in the Taurus molecular cloud. I. Physical properties of filaments and dense cores
We present deep NH3 observations of the L1495-B218 filaments in the Taurus molecular cloud covering over a 3° angular range using the K-band focal plane array on the 100 m Green Bank Telescope. The L1495-B218 filaments form an interconnected, nearby, large complex extending over 8 pc. We observed NH3 (1, 1) and (2, 2) with a spectral resolution of 0.038 km sâ1 and a spatial resolution of 31''. Most of the ammonia peaks coincide with intensity peaks in dust continuum maps at 350 and 500 Îźm. We deduced physical properties by fitting a model to the observed spectra. We find gas kinetic temperatures of 8â15 K, velocity dispersions of 0.05â0.25 km sâ1, and NH3 column densities of 5 Ă 1012 to 1 Ă 1014 cmâ2. The CSAR algorithm, which is a hybrid of seeded-watershed and binary dendrogram algorithms, identifies a total of 55 NH3 structures, including 39 leaves and 16 branches. The masses of the NH3 sources range from 0.05 to 9.5 . The masses of NH3 leaves are mostly smaller than their corresponding virial mass estimated from their internal and gravitational energies, which suggests that these leaves are gravitationally unbound structures. Nine out of 39 NH3 leaves are gravitationally bound, and seven out of nine gravitationally bound NH3 leaves are associated with star formation. We also found that 12 out of 30 gravitationally unbound leaves are pressure confined. Our data suggest that a dense core may form as a pressure-confined structure, evolve to a gravitationally bound core, and undergo collapse to form a protostar
Treatment of autosomal dominant hypocalcemia Type 1 with the calcilytic NPSP795 (SHP635)
Autosomal dominant hypocalcemia type 1 (ADH1) is a rare form of hypoparathyroidism caused by heterozygous, gainâofâfunction mutations of the calciumâsensing receptor gene (CAR). Individuals are hypocalcemic with inappropriately low parathyroid hormone (PTH) secretion and relative hypercalciuria. Calcilytics are negative allosteric modulators of the extracellular calcium receptor (CaR) and therefore may have therapeutic benefits in ADH1. Five adults with ADH1 due to 4 distinct CAR mutations received escalating doses of the calcilytic compound NPSP795 (SHP635) on 3 consecutive days. Pharmacokinetics, pharmacodynamics, efficacy, and safety were assessed. Parallel in vitro testing with subject CaR mutations assessed the effects of NPSP795 on cytoplasmic calcium concentrations (Ca2+i), and ERK and p38MAPK phosphorylation. These effects were correlated with clinical responses to administration of NPSP795. NPSP795 increased plasma PTH levels in a concentrationâdependent manner up to 129% above baseline (p=0.013) at the highest exposure levels. Fractional excretion of calcium (FECa) trended down but not significantly so. Blood ionized calcium levels remained stable during NPSP795 infusion despite fasting, no calcitriol and little calcium supplementation. NPSP795 was generally safe and wellâtolerated. There was significant variability in response clinically across genotypes. In vitro, all mutant CaRs were halfâmaximally activated (EC50) at lower concentrations of extracellular calcium (Ca2+o) compared to wild type (WT) CaR; NPSP795 exposure increased the EC50 for all CaR activity readouts. However, the in vitro responses to NPSP795 did not correlate with any clinical parameters. NPSP795 increased plasma PTH levels in subjects with ADH1 in a doseâdependent manner, and thus, serves as proofâofâconcept that calcilytics could be an effective treatment for ADH1. Albeit all mutations appear to be activating at the CaR, in vitro observations were not predictive of the in vivo phenotype, or the response to calcilytics, suggesting that other parameters impact the response to the drug
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