RESUMO
Effective engagement is crucial for enhancing environmental decision-making processes, fostering more sustainable and equitable outcomes. However, the success of engagement is highly variable and context-dependent. While theoretical frameworks have been developed to explain outcome variance in engagement in environmental decision-making, they have not yet been tested in digital contexts, leaving their applicability to digital engagement processes unclear. More broadly, there are unanswered questions about the effectiveness of digital tools in achieving the goals of engagement, which have become increasingly pertinent amidst growing concerns about the potential of digital technologies for exacerbating exclusions, ethical issues, and systematically undermining democratic progress. This paper addresses this evidence gap by presenting findings from interviews with practitioners in UK public, private, and third sector organisations. Our results provide empirical insights into the technical, ethical, and inclusivity debates surrounding digital tools and their effectiveness in promoting accessible engagement, high-quality social interaction, place-based decision-making, and more trustworthy and credible outcomes. Our findings indicate that while current engagement theories are applicable to digital environments, the key explanatory factors acquire new dimensions in digital compared to in-person contexts. Drawing on the findings, this study contributes novel insights to expand current theory for explaining "what works" in engagement in environmental decisions, enhancing its relevance and applicability in the digital age. The paper concludes with evidence-led recommendations for environmental practitioners to improve engagement processes in digital and remote settings.
Assuntos
Tomada de Decisões , Humanos , Tecnologia Digital , Conservação dos Recursos Naturais/métodosRESUMO
BACKGROUND: Folate, including the folic acid form, is a key component of the one-carbon metabolic pathway used for DNA methylation. Changes in DNA methylation patterns during critical development periods are associated with disease outcomes and are associated with changes in nutritional status in pregnancy. The long-term impact of periconceptional folic acid supplementation on DNA methylation patterns is unknown. OBJECTIVES: To determine the long-term impact of periconceptional folic acid supplementation on DNA methylation patterns, we examined the association of the recommended dosage (400 µg/d) and time period (periconceptional before pregnancy through first trimester) of folic acid supplementation with the DNA methylation patterns in the offspring at age 14-17 y compared with offspring with no supplementation. METHODS: Two geographic sites in China from the 1993-1995 Community Intervention Program of folic acid supplementation were selected for the follow-up study. DNA methylation at 402,730 CpG sites was assessed using saliva samples from 89 mothers and 179 adolescents (89 male). The mean age at saliva collection was 40 y among mothers (range: 35-54 y) and 15 y among adolescents (range: 14-17 y). Epigenome-wide analyses were conducted to assess the interactions of periconceptional folic acid exposure, the 5,10-methylenetetrahydrofolate reductase (MTHFR)-C677T genotype, and epigenome-wide DNA methylation controlling for offspring sex, geographic region, and background cell composition in the saliva. RESULTS: In the primary outcome, no significant differences were observed in epigenome-wide methylation patterns between adolescents exposed and those non-exposed to maternal periconceptional folic acid supplementation after adjustment for potential confounders [false discovery rate (FDR) P values < 0.05]. The MTHFR-C677T genotype did not modify this lack of association (FDR P values < 0.05). CONCLUSIONS: Overall, there were no differences in DNA methylation between adolescents who were exposed during the critical developmental window and those not exposed to the recommended periconceptional/first-trimester dosage of folic acid.
Assuntos
Metilação de DNA , Suplementos Nutricionais , Gravidez , Humanos , Adolescente , Feminino , Masculino , Seguimentos , Ácido Fólico/farmacologia , MãesRESUMO
BACKGROUND: Arsenic is a common environmental toxin. Exposure to arsenic (particularly its inorganic form) through contaminated food and drinking water is an important public health burden worldwide, and is associated with increased risk of neurotoxicity, congenital anomalies, cancer, and adverse neurodevelopment in children. Arsenic is excreted following methylation reactions, which are mediated by folate. Provision of folate through folic acid supplements could facilitate arsenic methylation and excretion, thereby reducing arsenic toxicity. OBJECTIVES: To assess the effects of provision of folic acid (through fortified foods or supplements), alone or in combination with other nutrients, in lessening the burden of arsenic-related health outcomes and reducing arsenic toxicity in arsenic-exposed populations. SEARCH METHODS: In September 2020, we searched CENTRAL, MEDLINE, Embase, 10 other international databases, nine regional databases, and two trials registers. SELECTION CRITERIA: Randomised controlled trials (RCTs) and quasi-RCTs comparing the provision of folic acid (at any dose or duration), alone or in combination with other nutrients or nutrient supplements, with no intervention, placebo, unfortified food, or the same nutrient or supplements without folic acid, in arsenic-exposed populations of all ages and genders. DATA COLLECTION AND ANALYSIS: We used standard methodological procedures expected by Cochrane. MAIN RESULTS: We included two RCTs with 822 adults exposed to arsenic-contaminated drinking water in Bangladesh. The RCTs compared 400 µg/d (FA400) or 800 µg/d (FA800) folic acid supplements, given for 12 or 24 weeks, with placebo. One RCT, a multi-armed trial, compared FA400 plus creatine (3 g/d) to creatine alone. We judged both RCTs at low risk of bias in all domains. Due to differences in co-intervention, arsenic exposure, and participants' nutritional status, we could not conduct meta-analyses, and therefore, provide a narrative description of the data. Neither RCT reported on cancer, all-cause mortality, neurocognitive function, or congenital anomalies. Folic acid supplements alone versus placebo Blood arsenic. In arsenic-exposed individuals, FA likely reduces blood arsenic concentrations compared to placebo (2 studies, 536 participants; moderate-certainty evidence). For folate-deficient and folate-replete participants who received arsenic-removal water filters as a co-intervention, FA800 reduced blood arsenic levels more than placebo (percentage change (%change) in geometric mean (GM) FA800 -17.8%, 95% confidence intervals (CI) -25.0 to -9.8; placebo GM -9.5%, 95% CI -16.5 to -1.8; 1 study, 406 participants). In one study with 130 participants with low baseline plasma folate, FA400 reduced total blood arsenic (%change FA400 mean (M) -13.62%, standard error (SE) ± 2.87; placebo M -2.49%, SE ± 3.25), and monomethylarsonic acid (MMA) concentrations (%change FA400 M -22.24%, SE ± 2.86; placebo M -1.24%, SE ± 3.59) more than placebo. Inorganic arsenic (InAs) concentrations reduced in both groups (%change FA400 M -18.54%, SE ± 3.60; placebo M -10.61%, SE ± 3.38). There was little to no change in dimethylarsinic acid (DMA) in either group. Urinary arsenic. In arsenic-exposed individuals, FA likely reduces the proportion of total urinary arsenic excreted as InAs (%InAs) and MMA (%MMA) and increases the proportion excreted as DMA (%DMA) to a greater extent than placebo (2 studies, 546 participants; moderate-certainty evidence), suggesting that FA enhances arsenic methylation. In a mixed folate-deficient and folate-replete population (1 study, 352 participants) receiving arsenic-removal water filters as a co-intervention, groups receiving FA had a greater decrease in %InAs (within-person change FA400 M -0.09%, 95% CI -0.17 to -0.01; FA800 M -0.14%, 95% CI -0.21 to -0.06; placebo M 0.05%, 95% CI 0.00 to 0.10), a greater decrease in %MMA (within-person change FA400 M -1.80%, 95% CI -2.53 to -1.07; FA800 M -2.60%, 95% CI -3.35 to -1.85; placebo M 0.15%, 95% CI -0.37 to 0.68), and a greater increase in %DMA (within-person change FA400 M 3.25%, 95% CI 1.81 to 4.68; FA800 M 4.57%, 95% CI 3.20 to 5.95; placebo M -1.17%, 95% CI -2.18 to -0.17), compared to placebo. In 194 participants with low baseline plasma folate, FA reduced %InAs (%change FA400 M -0.31%, SE ± 0.04; placebo M -0.13%, SE ± 0.04) and %MMA (%change FA400 M -2.6%, SE ± 0.37; placebo M -0.71%, SE ± 0.43), and increased %DMA (%change FA400 M 5.9%, SE ± 0.82; placebo M 2.14%, SE ± 0.71), more than placebo. Plasma homocysteine: In arsenic-exposed individuals, FA400 likely reduces homocysteine concentrations to a greater extent than placebo (2 studies, 448 participants; moderate-certainty evidence), in the mixed folate-deficient and folate-replete population receiving arsenic-removal water filters as a co-intervention (%change in GM FA400 -23.4%, 95% CI -27.1 to -19.5; placebo -1.3%, 95% CI -5.3 to 3.1; 1 study, 254 participants), and participants with low baseline plasma folate (within-person change FA400 M -3.06 µmol/L, SE ± 3.51; placebo M -0.05 µmol/L, SE ± 4.31; 1 study, 194 participants). FA supplements plus other nutrient supplements versus nutrient supplements alone In arsenic-exposed individuals who received arsenic-removal water filters as a co-intervention, FA400 plus creatine may reduce blood arsenic concentrations more than creatine alone (%change in GM FA400 + creatine -14%, 95% CI -22.2 to -5.0; creatine -7.0%, 95% CI -14.8 to 1.5; 1 study, 204 participants; low-certainty evidence); may not change urinary arsenic methylation indices (FA400 + creatine: %InAs M 13.2%, SE ± 7.0; %MMA M 10.8, SE ± 4.1; %DMA M 76, SE ± 7.8; creatine: %InAs M 14.8, SE ± 5.5; %MMA M 12.8, SE ± 4.0; %DMA M 72.4, SE ±7.6; 1 study, 190 participants; low-certainty evidence); and may reduce homocysteine concentrations to a greater extent (%change in GM FA400 + creatinine -21%, 95% CI -25.2 to -16.4; creatine -4.3%, 95% CI -9.0 to 0.7; 1 study, 204 participants; low-certainty evidence) than creatine alone. AUTHORS' CONCLUSIONS: There is moderate-certainty evidence that FA supplements may benefit blood arsenic concentration, urinary arsenic methylation profiles, and plasma homocysteine concentration versus placebo. There is low-certainty evidence that FA supplements plus other nutrients may benefit blood arsenic and plasma homocysteine concentrations versus nutrients alone. No studies reported on cancer, all-cause mortality, neurocognitive function, or congenital anomalies. Given the limited number of RCTs, more studies conducted in diverse settings are needed to assess the effects of FA on arsenic-related health outcomes and arsenic toxicity in arsenic-exposed adults and children.
Assuntos
Arsênio , Adulto , Criança , Creatina , Suplementos Nutricionais , Ácido Fólico , Alimentos Fortificados , HumanosRESUMO
Background Reducing pregnancy risk requires a multidimensional approach to sexual and reproductive health product development. The purpose of this analysis is to identify, compare, and contrast women's pre-use beliefs and attitudes about three different forms of contraceptives: intravaginal rings; spermicide in conjunction with condoms; and oral contraceptive pills - and explore how those attitudes and beliefs, along with actual method-use experience, may affect potential choices in contraceptive method moving forward. The relationship of beliefs and attitudes to their risk-benefit calculations when using these methods was also considered.? METHODS: Women used one or more contraceptive methods, each for 3-6 months. Qualitative data from individual in-depth interviews completed after each 3-month use period were analysed using a summary matrix framework. Data were extracted and summarised into themes. Each woman's experiences were compared among the methods she used; comparisons were also made across participants. RESULTS: The data consist of 33 90-120 min in-depth qualitative interviews from 16 women aged 20-34 years, in which they discussed various elements of their method use experience. One prominent theme was identified: the influence of attitudes and beliefs on the risk-benefit calculus. There were six key elements within the theme: pregnancy prevention; dosing and the potential for user error; side-effects; familiarity; disclosure; and sexual partnerships. CONCLUSIONS: Women weighed perceived risks and benefits in their decision-making and, ultimately, their contraception choices. Understanding women's beliefs and attitudes that contribute to a calculation of risk-benefit can inform the development of sexual and reproductive health products.
Assuntos
Comportamento de Escolha , Anticoncepção/métodos , Anticoncepção/psicologia , Tomada de Decisões , Conhecimentos, Atitudes e Prática em Saúde , Adulto , Preservativos , Dispositivos Anticoncepcionais Femininos , Anticoncepcionais Orais , Feminino , Humanos , Massachusetts , Pesquisa Qualitativa , Rhode Island , Medição de Risco , Espermicidas , Adulto JovemRESUMO
BACKGROUND: Previous studies noted associations between birth defects and some antibiotics (e.g., nitrofurantoin, sulfonamides) but not others (e.g., penicillins). It is unclear if previous findings were due to antibiotic use, infections, or chance. To control for potential confounding by indication, we examined associations between antibiotic use and birth defects, among women reporting urinary tract infections (UTIs). METHODS: The National Birth Defects Prevention Study is a multi-site, population-based case-control study. Case infants/fetuses have any of over 30 major birth defects and controls are live-born infants without major birth defects. We analyzed pregnancies from 1997 to 2011 to estimate the association between maternally reported periconceptional (month before conception through the third month of pregnancy) use of nitrofurantoin, trimethoprim-sulfamethoxazole, or cephalosporins and specific birth defects, among women with periconceptional UTIs. Women with periconceptional UTIs who reported penicillin use served as the comparator. RESULTS: Periconceptional UTIs were reported by 7.8% (2029/26,068) of case and 6.7% (686/10,198) of control mothers. Most (68.2% of case, 66.6% of control mothers) also reported antibiotic use. Among 608 case and 231 control mothers reporting at least one periconceptional UTI and certain antibiotic use, compared with penicillin, nitrofurantoin use was associated with oral clefts in the offspring (adjusted odds ratio, 1.97 [95% confidence interval, 1.10-3.53]), trimethoprim-sulfamethoxazole use with esophageal atresia (5.31 [1.39-20.24]) and diaphragmatic hernia (5.09 [1.20-21.69]), and cephalosporin use with anorectal atresia/stenosis (5.01 [1.34-18.76]). CONCLUSION: Periconceptional exposure to some antibiotics might increase the risk for certain birth defects. However, because individual birth defects are rare, absolute risks should drive treatment decisions.Birth Defects Research (Part A) 106:940-949, 2016.© 2016 Wiley Periodicals, Inc.
Assuntos
Anormalidades Induzidas por Medicamentos/epidemiologia , Programas Nacionais de Saúde , Complicações Infecciosas na Gravidez , Primeiro Trimestre da Gravidez , Infecções Urinárias , Antibacterianos , Feminino , Humanos , Gravidez , Complicações Infecciosas na Gravidez/tratamento farmacológico , Complicações Infecciosas na Gravidez/epidemiologia , Estudos Retrospectivos , Fatores de Risco , Estados Unidos/epidemiologia , Infecções Urinárias/tratamento farmacológico , Infecções Urinárias/epidemiologiaRESUMO
The ß-barrel nitrophorin (NP) heme proteins are found in the saliva of the blood-sucking insect Rhodnius prolixus, which synthesizes and stores nitric oxide (NO) in the salivary glands. NO is bound to iron of the NPs and is released by dilution and an increase in pH when the insect spits its saliva into the tissues of a victim, to aid in obtaining a blood meal. In the adult insect, there are four nitrophorins, NP1-NP4, which have sequence similarities in two pairs, NP1 and NP4 (90% identical) and NP2 and NP3 (80% identical). The available crystal structures of NP4 have been used to propose that pH-dependent changes in the conformation of two loops between adjacent ß-strands at the front opening of the protein, the A-B and G-H loops, determine the rate of NO release. At pH 7.3, NP4 releases NO 17 times faster than NP2 does. In this work, the aqua complexes of NP4 and NP2 have been investigated by nuclear magnetic resonance (NMR) relaxation measurements to probe the pico- to nanosecond and micro- to millisecond time scale motions at two pH values, 6.5 and 7.3. It is found that NP4-OH2 is fairly rigid and only residues in the loop regions show dynamics at pH 6.5; at pH 7.3, much more dynamics of the loops and most of the ß-strands are observed while the α-helices remain fairly rigid. In comparison, NP2-OH2 shows much less dynamics, albeit somewhat more than that of the previously reported NP2-NO complex [Muthu, D., Berry, R. E., Zhang, H., and Walker, F. A. (2013) Biochemistry 52, 7910-7925]. The reasons for this major difference between NP4 and NP2 are discussed.
Assuntos
Hemeproteínas/química , Proteínas de Insetos/química , Rhodnius/química , Proteínas e Peptídeos Salivares/química , Animais , Concentração de Íons de Hidrogênio , Simulação de Dinâmica Molecular , Ressonância Magnética Nuclear Biomolecular , Conformação ProteicaRESUMO
Nitrophorin 4, one of the four NO-carrying heme proteins from the salivary glands of Rhodnius prolixus, forms a homodimer at pH 5.0 with a Kd of â¼8 µM. This dimer begins to dissociate at pH 5.5 and is completely dissociated to monomer at pH 7.3, even at 3.7 mM. The dimer is significantly stabilized by binding NO to the heme and at pH 7.3 would require dilution to well below 0.2 mM to completely dissociate the NP4-NO homodimer. The primary techniques used for investigating the homodimer and the monomer-dimer equilibrium were size-exclusion fast protein liquid chromatography at pH 5.0 and (1)H{(15)N} heteronuclear single-quantum coherence spectroscopy as a function of pH and concentration. Preparation of site-directed mutants of NP4 (A1K, D30A, D30N, V36A/D129A/L130A, K38A, R39A, K125A, K125E, D132A, L133V, and K38Q/R39Q/K125Q) showed that the N-terminus, D30, D129, D132, at least one heme propionate, and, by association, likely also E32 and D35 are involved in the dimerization. The "closed loop" form of the A-B and G-H flexible loops of monomeric NP4, which predominates in crystal structures of the monomeric protein reported at pH 5.6 but not at pH 7.5 and which involves all of the residues listed above except D132, is required for dimer formation. Wild-type NP1 does not form a homodimer, but NP1(K1A) and native N-terminal NP1 form dimers in the presence of NO. The homodimer of NP1, however, is considerably less stable than that of NP4 in the absence of NO. This suggests that additional aspartate or glutamate residues present in the C-terminal region of NP4, but not NP1, are also involved in stabilizing the dimer.
Assuntos
Hemeproteínas/química , Proteínas de Insetos/química , Multimerização Proteica , Rhodnius/química , Proteínas e Peptídeos Salivares/química , Animais , Cristalografia por Raios X , Hemeproteínas/genética , Concentração de Íons de Hidrogênio , Proteínas de Insetos/genética , Modelos Moleculares , Mutagênese Sítio-Dirigida , Mutação Puntual , Rhodnius/genética , Proteínas e Peptídeos Salivares/genéticaRESUMO
The Biomarkers of Nutrition for Development (BOND) project is designed to provide evidence-based advice to anyone with an interest in the role of nutrition in health. Specifically, the BOND program provides state-of-the-art information and service with regard to selection, use, and interpretation of biomarkers of nutrient exposure, status, function, and effect. To accomplish this objective, expert panels are recruited to evaluate the literature and to draft comprehensive reports on the current state of the art with regard to specific nutrient biology and available biomarkers for assessing nutrients in body tissues at the individual and population level. Phase I of the BOND project includes the evaluation of biomarkers for 6 nutrients: iodine, iron, zinc, folate, vitamin A, and vitamin B-12. This review represents the second in the series of reviews and covers all relevant aspects of folate biology and biomarkers. The article is organized to provide the reader with a full appreciation of folate's history as a public health issue, its biology, and an overview of available biomarkers (serum folate, RBC folate, and plasma homocysteine concentrations) and their interpretation across a range of clinical and population-based uses. The article also includes a list of priority research needs for advancing the area of folate biomarkers related to nutritional health status and development.
Assuntos
Biomarcadores/sangue , Ácido Fólico/sangue , Suplementos Nutricionais , Ácido Fólico/administração & dosagem , Humanos , Iodo/sangue , Ferro/sangue , Avaliação Nutricional , Estado Nutricional , Recomendações Nutricionais , Vitamina A/sangue , Vitamina B 12/sangue , Zinco/sangueRESUMO
Nitrophorin 2 (NP2), one of the four NO-storing and NO-releasing proteins found in the saliva of the blood-sucking bug Rhodnius prolixus, has a more ruffled heme and a high preference for a particular heme orientation (B) compared with nitrophorin 1 and nitrophorin 4, which show not a preference (A to B ratio of approximately 1:1), suggesting that it fits more tightly in the ß-barrel protein. In this work we have prepared a series of "belt" mutants of NP2(D1A) and (ΔM0)NP2 aimed at reducing the size of aromatic or other residues that surround the heme, and investigated them as the high-spin aqua and low-spin N-methylimidazole complexes. The belt mutants included Y38A, Y38F, F42A, F66A, Y85A, Y85F, Y104A, I120T, and a triple mutant of NP2(D1A), the F42L, L106F, I120T mutant. Although I120 has been mainly considered to be a distal pocket residue, CδH3 of I120 lies directly above the heme 3-methyl, at 2.67 Å, of heme orientation B, or the 2-vinyl of A, and it thus plays a role as a belt mutant, a role that turns out to be extremely important in creating the strong favoring of the B heme orientation [A to B ratio of 1:14 for NP2(D1A) or 1:12 for (ΔM0)NP2]. The results show that the 1D (1)H NMR spectra of the high-spin forms are quite sensitive to changes in the shape of the heme binding cavity. The single mutation I120T eliminates the favorability of the B heme orientation by producing a heme A to B orientation ratio of 1:1, whereas the single mutation F42A reverses the heme orientation from an A to B ratio of 1:14 seen for NP2(D1A) to 10:1 for NP2(D1A,F42A). The most extreme ratio was found for the triple mutant of NP2(D1A), NP2(D1A,F42L,L105F,I120T), in which the A to B ratio is approximately 25:1, a ΔG change of about -3.5 kcal/mol or -14.1 kJ/mol with respect to NP2(D1A). The seating of the heme is modified as well in that mutant and in several others, by rotations of the heme by up to 4° from the seating observed in NP2(D1A), in order to relieve steric interactions between a vinyl ß-carbon and a protein side chain, or to fill a cavity created by replacing a large protein side chain by a much smaller one; the latter was observed for all tyrosine to alanine mutants. These relatively small changes in seating have a measurable effect on the NMR spectra of the mutants, but are indeed minor in terms of overall seating and reactivity of the NP2(D1A) protein. The (1)H NMR resonances of the hemin substituents of the low-spin N-methylimidazole complexes of NP2(D1A,F42L,L105F,I120T) as well as NP2(D1A,I120T), NP2(D1A,Y104A), and NP2(D1A,F42A) have been assigned using natural abundance (1)H{(13)C} heteronuclear multiple quantum correlation and (1)H-(1)H nuclear Overhauser effect spectroscopy spectra.
Assuntos
Heme/química , Heme/metabolismo , Hemeproteínas/química , Hemeproteínas/metabolismo , Espectroscopia de Ressonância Magnética/métodos , Proteínas e Peptídeos Salivares/química , Proteínas e Peptídeos Salivares/metabolismo , Hemeproteínas/genética , Mutagênese Sítio-Dirigida , Proteínas e Peptídeos Salivares/genética , TermodinâmicaRESUMO
Whether folic acid fortification and supplementation at the population level have led to a higher prevalence of vitamin B-12 deficiency in the absence of anemia remains to be examined among a nationally representative sample of older U.S. adults. We assessed the prevalence of low vitamin B-12 status in the absence of anemia or macrocytosis before and after fortification among adults aged >50 y using cross-sectional data from the NHANES 1991-1994 (prefortification) and 2001-2006 (postfortification). We compared the prefortification and postfortification prevalence of multiple outcomes, including serum vitamin B-12 deficiency (<148 pmol/L) and marginal deficiency (148-258 pmol/L) with and without anemia (hemoglobin <130 g/L for men, <120 g/L for women) and with and without macrocytosis (mean cell volume >100 fL) using multinomial logistic regression, adjusting for age, sex, ethnicity, body mass index, C-reactive protein, and vitamin B-12 supplement use. Prefortification and postfortification serum vitamin B-12 deficiency without anemia [4.0 vs. 3.9%; adjusted prevalence ratio (aPR) (95% CI): 0.98 (0.67, 1.44)] or without macrocytosis [4.2 vs. 4.1%; aPR (95% CI): 0.96 (0.65, 1.43)] remained unchanged. Marginal deficiency without anemia [25.1 vs. 20.7%; aPR (95% CI): 0.82 (0.72, 0.95)] or without macrocytosis [25.9 vs. 21.3%; aPR (95% CI): 0.82 (0.72, 0.94)] were both significantly lower after fortification. After fortification, higher folic acid intake was associated with a lower prevalence of low serum B-12 status in the absence of anemia or macrocytosis. Results suggest that the prevalence of low serum B-12 status in the absence of anemia or macrocytosis among older U.S. adults did not increase after fortification. Thus, at the population level, we found no evidence to support concerns that folic acid adversely affected the clinical presentation of vitamin B-12 deficiency among older adults.
Assuntos
Suplementos Nutricionais , Ácido Fólico/farmacologia , Alimentos Fortificados , Hemoglobinas/metabolismo , Deficiência de Vitamina B 12/epidemiologia , Vitamina B 12/sangue , Complexo Vitamínico B , Idoso , Anemia Macrocítica/sangue , Estudos Transversais , Dieta , Feminino , Ácido Fólico/efeitos adversos , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Inquéritos Nutricionais , Prevalência , Estados Unidos/epidemiologia , Deficiência de Vitamina B 12/sangue , Deficiência de Vitamina B 12/etiologia , Complexo Vitamínico B/efeitos adversos , Complexo Vitamínico B/sangue , Complexo Vitamínico B/farmacologiaRESUMO
Stormwater catch basins are the primary source of mosquitoes targeted by the North Shore Mosquito Abatement District, in the northern suburbs of Chicago. Over a 17-wk period (June to September 2011), 3 clusters of catch basins located within a 0.7-km2 area were monitored weekly with dipper samples of immature mosquitoes. During the 2nd week of monitoring, Natular XRT tablets (6.25% spinosad) were applied to northernmost cluster and FourStar Briquets (6% Bacillus û, 1% Bacillus thuringiensis israelensis) were applied to the southernmost cluster; the remaining middle cluster was kept untreated. Following 15 wk of monitoring in 20 basins in each cluster, both Natular and FourStar reduced immature numbers in treated catch basins for 8 consecutive weeks. These results suggest, if effectively timed, a single application of either larvicide may last an entire season.
Assuntos
Bacillus , Culicidae , Inseticidas , Macrolídeos , Controle de Mosquitos/métodos , Animais , Chicago , Culicidae/crescimento & desenvolvimento , Combinação de Medicamentos , Larva/crescimento & desenvolvimento , Fatores de TempoRESUMO
Alleviation of headaches (HAs), neck pain (NP), and disability is a desirable clinical outcome for the billions globally who suffer from these conditions. Chiropractic BioPhysics® (CBP®) methods may provide an option for head and neck-injured patients. A 62-year-old female historically injured multiple times including two motor vehicle collisions (MVC), and a strike to the face with a hockey puck; all resulting in chronic pain and suffering. The subject sought and received successful treatment in 2016 using this conservative protocol at a facility in the USA. The resolution of symptoms following 36 treatments was previously reported. Following 13 years without treatment beyond home exercises, the subject was re-evaluated and found to be stable in the long term for pain, structural and functional assessment. Thirty-six treatments over 12 weeks in 2016 led to an improvement in numerical pain rating scale (NPRS) for NP (5/10 to 1/10), and HA (9+/10 to 0/10), resolution of NP disability (6/100 to 0/100) as well as normalization of ROM without pain and resumption of all activities of daily living including high-level athletics without pain and disability. A 13-year follow-up found continued stability objectively and subjectively. We provide a case of successful conservative treatment using specific traction, exercises, and spine manipulation procedures. CBP® provides an option to treat pain and this case adds to growing evidence.
RESUMO
The Rhodnius nitrophorins are ß-barrel proteins of the lipocalin fold with a heme protruding from the open end of the barrel. They are found in the saliva of the blood-sucking insect Rhodnius prolixus, which synthesizes and stores nitric oxide (NO) in the salivary glands, where NO is bound to iron. NO is released by dilution and an increase in pH when the insect spits its saliva into the tissues of a victim, to aid in obtaining a blood meal. In the adult insect, there are four nitrophorins, NP1-NP4. At pH 7.3, NP4 releases NO 17 times faster than NP2 does, as measured by stopped-flow kinetics. A number of crystal structures of the least abundant protein, NP4, are available. These structures have been used to propose that two loops between adjacent ß-strands at the front opening of the protein, the A-B and G-H loops, determine the rate of NO release. To learn how the protein loops contribute to the release of NO for each of the nitrophorins, the dynamics of these proteins are being studied in our laboratory. In this work, the NP2-NO complex has been investigated by nuclear magnetic resonance relaxation measurements to probe the picosecond-to-nanosecond and microsecond-to-millisecond time scale motions at three pH values, 5.0, 6.5, and 7.3. It is found that at pH 5.0 and 6.5, the NP2-NO complex is rigid and only a few residues in the loop regions show dynamics, while at pH 7.3, somewhat more dynamics, particularly of the A-B loop, are observed. Comparison to other lipocalins shows that all are relatively rigid, and that the dynamics of lipocalins in general are much more subtle than those of mainly α-helical proteins.
Assuntos
Hemeproteínas/química , Hemeproteínas/metabolismo , Espectroscopia de Ressonância Magnética/métodos , Óxido Nítrico/química , Óxido Nítrico/metabolismo , Proteínas e Peptídeos Salivares/química , Proteínas e Peptídeos Salivares/metabolismo , Animais , Concentração de Íons de Hidrogênio , Ligação ProteicaRESUMO
A triad of tyrosine residues (Y152-154) in the cytochrome c(1) subunit (C1) of the Rhodobacter capsulatus cytochrome bc(1) complex (BC1) is ideally positioned to interact with cytochrome c(2) (C2). Mutational analysis of these three tyrosines showed that, of the three, Y154 is the most important, since its mutation to alanine resulted in significantly reduced levels, destabilization, and inactivation of BC1. A second-site revertant of this mutant that regained photosynthetic capacity was found to have acquired two further mutations-A181T and A200V. The Y152Q mutation did not change the spectral or electrochemical properties of C1, and showed wild-type enzymatic C2 reduction rates, indicating that this mutation did not introduce major structural changes in C1 nor affect overall activity. Mutations Y153Q and Y153A, on the other hand, clearly affect the redox properties of C1 (e.g. by lowering the midpoint potential as much as 117 mV in Y153Q) and the activity by 90% and 50%, respectively. A more conservative Y153F mutant on the other hand, behaves similarly to wild-type. This underscores the importance of an aromatic residue at position Y153, presumably to maintain close packing with P184, which modeling indicates is likely to stabilize the sixth heme ligand conformation.
Assuntos
Citocromos c1/metabolismo , Citocromos c2/metabolismo , Complexo III da Cadeia de Transporte de Elétrons/metabolismo , Rhodobacter capsulatus/metabolismo , Tirosina/metabolismo , Sequência de Aminoácidos , Animais , Biocatálise , Citocromos c1/química , Citocromos c2/química , Complexo III da Cadeia de Transporte de Elétrons/química , Eletroforese em Gel de Poliacrilamida , Heme/química , Modelos Moleculares , Dados de Sequência Molecular , Mutação/genética , Rhodobacter capsulatus/crescimento & desenvolvimento , Alinhamento de Sequência , Análise EspectralRESUMO
Sulfite oxidase (SO) is a vital metabolic enzyme that catalyzes the oxidation of toxic sulfite to sulfate. The proposed mechanism of this molybdenum cofactor dependent enzyme involves two one-electron intramolecular electron transfer (IET) steps from the molybdenum center to the iron of the b 5-type heme and two one-electron intermolecular electron transfer steps from the heme to cytochrome c. This work focuses on how the electrostatic interaction between two conserved amino acid residues, R472 and D342, in human SO (hSO) affects catalysis. The hSO variants R472M, R472Q, R472K, R472D, and D342K were created to probe the effect of the position of the salt bridge charges, along with the interaction between these two residues. With the exception of R472K, these variants all showed a significant decrease in their IET rate constants, k et, relative to wild-type hSO, indicating that the salt bridge between residues 472 and 342 is important for rapid IET. Surprisingly, however, except for R472K and R472D, all of the variants show k cat values higher than their corresponding k et values. The turnover number for R472D is about the same as k et, which suggests that the change in this variant is rate-limiting in catalysis. Direct spectroelectrochemical determination of the Fe(III/II) reduction potentials of the heme and calculation of the Mo(VI/V) potentials revealed that all of the variants affected the redox potentials of both metal centers, probably due to changes in their environments. Thus, the position of the positive charge of R472 and that of the negative charge of D342 are both important in hSO, and changing either the position or the nature of these charges perturbs IET and catalysis.
Assuntos
Oxirredutases atuantes sobre Doadores de Grupo Enxofre/metabolismo , Sais/metabolismo , Transporte de Elétrons , Humanos , Cinética , Lasers , Modelos Moleculares , Mutagênese Sítio-Dirigida , Oxirredutases atuantes sobre Doadores de Grupo Enxofre/química , Oxirredutases atuantes sobre Doadores de Grupo Enxofre/genética , Fotólise , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Sais/químicaRESUMO
The electronic structure of heme proteins is exquisitely tuned by the interaction of the iron center with the axial ligands. NMR studies of paramagnetic heme systems have been focused on the heme signals, but signals from the axial ligands have been rather difficult to detect and assign. We report an extensive assignment of the (1)H, (13)C and (15)N resonances of the axial His ligand in the NO-carrying protein nitrophorin 2 (NP2) in the paramagnetic high-spin and low-spin forms, as well as in the diamagnetic NO complex. We find that the high-spin protein has σ spin delocalization to all atoms in the axial His57, which decreases in size as the number of bonds between Fe(III) and the atom in question increases, except that within the His57 imidazole ring the contact shifts are a balance between positive σ and negative π contributions. In contrast, the low-spin protein has π spin delocalization to all atoms of the imidazole ring. Our strategy, adequately combined with a selective residue labeling scheme, represents a straightforward characterization of the electron spin density in heme axial ligands.
Assuntos
Elétrons , Hemeproteínas/química , Ressonância Magnética Nuclear Biomolecular , Proteínas e Peptídeos Salivares/química , Humanos , Ligantes , Modelos MolecularesRESUMO
BACKGROUND: In 2009, the Institute of Medicine revised gestational weight gain recommendations; revisions included body mass index (BMI) category cut-point changes and provision of range of gain for obese women. Our objective was to examine resident prenatal caregivers' knowledge of revised guidelines. METHODS: Anonymous electronic survey of obstetrics/gynecology and family medicine residents across the United States from January to April 2010. RESULTS: Overall, 660 completed the survey; 79 percent female and 69 percent aged between 21 and 30. When permitted to select ≥ 1 response, 87.0 percent reported using BMI to assess weight status at initial visits, 44.4 percent reported using "clinical impression based on patient appearance," and 1.4 percent reported not using any parameters. When asked the most important baseline parameter for providing recommendations, 35.8 percent correctly identified prepregnancy BMI, 2.1 percent reported "I don't provide guidelines," and 4.5 percent reported "I do not discuss gestational weight gain." Among respondents, 57.6 percent reported not being aware of new guidelines. Only 7.6 percent selected correct BMI ranges for each category, and only 5.8 percent selected correct gestational weight gain ranges. Only 2.3 percent correctly identified both BMI cutoffs and recommended gestational weight gain ranges per 2009 guidelines. CONCLUSIONS: Guideline knowledge is the foundation of accurate counseling, yet resident prenatal caregivers were minimally aware of the 2009 Institute of Medicine gestational weight gain guidelines almost a year after their publication.
Assuntos
Competência Clínica/estatística & dados numéricos , Aconselhamento Diretivo/normas , Fidelidade a Diretrizes/estatística & dados numéricos , Guias de Prática Clínica como Assunto , Padrões de Prática Médica/estatística & dados numéricos , Cuidado Pré-Natal/normas , Aumento de Peso , Adulto , Índice de Massa Corporal , Coleta de Dados , Aconselhamento Diretivo/estatística & dados numéricos , Medicina de Família e Comunidade/educação , Medicina de Família e Comunidade/normas , Feminino , Ginecologia/educação , Ginecologia/normas , Humanos , Internato e Residência , Masculino , National Academies of Science, Engineering, and Medicine, U.S., Health and Medicine Division , Obstetrícia/educação , Obstetrícia/normas , Gravidez , Cuidado Pré-Natal/estatística & dados numéricos , Estados UnidosRESUMO
In the northern suburbs of Chicago, stormwater catch basins are the primary source of vector mosquitoes targeted by the local mosquito abatement district, and therefore effective catch basin larvicides are needed. From June to September 2011, Natular XRT was applied at label rate to a cluster of 20 catch basins and compared to a cluster of 20 untreated basins all within a small 0.21 km2 area of catch basins known historically to have high levels of mosquitoes. All monitored basins held immature stages of mosquitoes at least once; however, significantly fewer immatures overall were observed from Natular-treated basins than in untreated basins during 14 wk of monitoring. During the study a portion of Natular-treated catch basins was cleaned as part of scheduled maintenance, and this appeared to remove both the larvicide and any control effects. Better timing of catch basin maintenance events is suggested, particularly if, as the results of this study suggest, a single larvicide treatment may be effective for an entire season.
Assuntos
Culicidae , Insetos Vetores , Inseticidas/administração & dosagem , Macrolídeos/administração & dosagem , Controle de Mosquitos , Animais , Chicago , Combinação de Medicamentos , Insetos Vetores/efeitos dos fármacos , Controle de Mosquitos/métodosRESUMO
The global coronavirus disease 2019 (COVID-19) pandemic prompted widespread national shutdown, halting or dramatically reducing the delivery of non-essential outpatient services including cardiac rehabilitation (CR). Center-based CR services were closed for as few as two weeks to greater than one year and the uncertainty surrounding the duration of the lockdown phase prompted programs to consider programmatic adaptations that would allow for the safe and effective delivery of CR services. Among the actions taken to accommodate in person CR sessions included increasing the distance between exercise equipment and/or limiting the number of patients per session. Legislative approval of reimbursing telehealth or virtual services presented an opportunity to reach patients that may otherwise have not considered attending CR during or even before the pandemic. Additionally, the considerable range of symptoms and infection severity as well as the risk of developing long lasting, debilitating symptoms has complicated exercise recommendations. Important lessons from publications reporting findings from clinical settings have helped shape the way in which exercise is applied, with much more left to discover. The overarching aim of this paper is to review how programs adapted to the COVID-19 pandemic and identify lessons learned that have positively influenced the future of CR delivery.
Assuntos
COVID-19 , Reabilitação Cardíaca , Telemedicina , Humanos , COVID-19/epidemiologia , Pandemias/prevenção & controle , Controle de Doenças TransmissíveisRESUMO
OBJECTIVES: To examine the potential for bias in the estimate of under-5 mortality due to birth defects recently produced by the WHO and the Maternal and Child Epidemiology Estimation research group. DESIGN: Systematic analysis. METHODS: We examined the estimated number of under-5 deaths due to birth defects, the birth defect specific under-5 mortality rate, and the per cent of under-5 mortality due to birth defects, by geographic region, national income and under-5 mortality rate for three age groups from 2000 to 2019. RESULTS: The under-5 deaths per 1000 live births from birth defects fell from 3.4 (95% uncertainty interval (UI) 3.1-3.8) in 2000 to 2.9 (UI 2.6-3.3) in 2019. The per cent of all under-5 mortality attributable to birth defects increased from 4.6% (UI 4.1%-5.1%) in 2000 to 7.6% (UI 6.9%-8.6%) in 2019. There is significant variability in mortality due to birth defects by national income level. In 2019, the under-5 mortality rate due to birth defects was less in high-income countries than in low-income and middle-income countries, 1.3 (UI 1.2-1.3) and 3.0 (UI 2.8-3.4) per 1000 live births, respectively. These mortality rates correspond to 27.7% (UI 26.6%-28.8%) of all under-5 mortality in high-income countries being due to birth defects, and 7.4% (UI 6.7%-8.2%) in low-income and middle-income countries. CONCLUSIONS: While the under-5 mortality due to birth defects is declining, the per cent of under-5 mortality attributable to birth defects has increased, with significant variability across regions globally. The estimates in low-income and middle-income countries are likely underestimated due to the nature of the WHO estimates, which are based in part on verbal autopsy studies and should be taken as a minimum estimate. Given these limitations, comprehensive and systematic estimates of the mortality burden due to birth defects are needed to estimate the actual burden.