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1.
BMJ Open ; 13(11): e074845, 2023 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-37973543

RESUMO

OBJECTIVES: Opioid use disorder (OUD) is a major public health concern in the USA, resulting in high rates of overdose and other negative outcomes. Methadone, an OUD treatment, has been shown to be effective in reducing the risk of overdose and improving overall health and quality of life. This study analysed the distribution of methadone for the treatment of OUD across the USA over the past decade and through the COVID-19 pandemic. DESIGN: Retrospective observational study using secondary data analysis of the Drug Enforcement Administration and Medicaid Databases. SETTING: USA. PARTICIPANTS: Patients who were dispensed methadone at US opioid treatment programmes (OTPs). PRIMARY AND SECONDARY OUTCOME MEASURES: The primary outcomes were the overall pattern in methadone distribution and the number of OTPs in the USA per year. The secondary outcome was Medicaid prescriptions for methadone. RESULTS: Methadone distribution for OUD has expanded significantly over the past decade, with an average state increase of +96.96% from 2010 to 2020. There was a significant increase in overall distribution of methadone to OTP from 2010 to 2020 (+61.00%, p<0.001) and from 2015 to 2020 (+26.22%, p<0.001). However, the distribution to OTPs did not significantly change from 2019 to 2021 (-5.15%, p=0.491). There was considerable state-level variation in methadone prescribing to Medicaid patients with four states having no prescriptions. CONCLUSIONS: There have been dynamic changes in methadone distribution for OUD. Furthermore, pronounced variation in methadone distribution among states was observed, with some states having no OTPs or Medicaid coverage. New policies are urgently needed to increase access to methadone treatment, address the opioid epidemic in the USA and reduce overdose deaths.


Assuntos
COVID-19 , Overdose de Drogas , Transtornos Relacionados ao Uso de Opioides , Estados Unidos/epidemiologia , Humanos , Metadona/uso terapêutico , Pandemias , Qualidade de Vida , Tratamento de Substituição de Opiáceos/métodos , COVID-19/epidemiologia , Transtornos Relacionados ao Uso de Opioides/tratamento farmacológico , Transtornos Relacionados ao Uso de Opioides/epidemiologia , Analgésicos Opioides/uso terapêutico , Overdose de Drogas/epidemiologia , Overdose de Drogas/tratamento farmacológico
2.
Am J Hum Biol ; 34(4): e23667, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34418235

RESUMO

OBJECTIVE: To test the "vitamin D-folate hypothesis for the evolution of human skin pigmentation." METHODS: Total ozone mapping spectrometer (TOMS) satellite data were used to examine surface UV-irradiance in a large (n = 649) Australian cross-sectional study population. Genetic analysis was used to score vitamin D- and folate-related gene polymorphisms (n = 22), along with two pigmentation gene variants (IRF4-rs12203592/HERC2-rs12913832). Red cell folate and vitamin D3 were measured by immunoassay and HPLC, respectively. RESULTS: Ultraviolet radiation (UVR) and pigmentation genes interact to modify blood vitamin levels; Light skin IRF4-TT genotype has greatest folate loss while light skin HERC2-GG genotype has greatest vitamin D3 synthesis (reflected in both TOMS and seasonal data). UV-wavelength exhibits a dose-response relationship in folate loss within light skin IRF4-TT genotype (305 > 310 > 324 > 380 nm). Significant vitamin D3 photosynthesis only occurs within light skin HERC2-GG genotype, and is maximal at 305 nm. Three dietary antioxidants (vitamins C, E, and ß-carotene) interact with UVR and pigmentation genes preventing oxidative loss of labile reduced folate vitamers, with greatest benefit in light skin IRF4-TT subjects. The putative photosensitiser, riboflavin, did not sensitize red cell folate to UVR and actually afforded protection. Four genes (5xSNPs) influenced blood vitamin levels when stratified by pigmentation genotype; MTHFR-rs1801133/rs1801131, TS-rs34489327, CYP24A-rs17216707, and VDR-ApaI-rs7975232. Lightest IRF4-TT/darkest HERC2-AA genotype combination (greatest folate loss/lowest vitamin D3 synthesis) has 0% occurrence. The opposing, commonest (39%) compound genotype (darkest IRF4-CC/lightest HERC2-GG) permits least folate loss and greatest synthesis of vitamin D3 . CONCLUSION: New biophysical evidence supports the vitamin D-folate hypothesis for evolution of skin pigmentation.


Assuntos
Pigmentação da Pele , Vitamina D , Austrália , Estudos Transversais , Ácido Fólico , Genótipo , Humanos , Pigmentação da Pele/genética , Raios Ultravioleta/efeitos adversos , Vitaminas
3.
Ann Pharmacother ; 56(3): 271-279, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34184584

RESUMO

BACKGROUND: Methadone is an evidence-based treatment for opioid use disorder (OUD) and pain management. Methadone for OUD may be difficult for some patients to access, particularly those in rural areas. OBJECTIVE: The purpose of this study was to characterize methadone distribution patterns between 2017 and 2019 across the United States. METHODS: The US Drug Enforcement Administration's Automated Reports and Consolidated Ordering System was used to acquire the number of opioid treatment programs (OTPs) per state and methadone distribution weight in grams. Methadone distributions by weight, corrected for state population and number of OTPs, were compared from 2017 to 2019 between states, within regions, and nationally. RESULTS: The national distribution of methadone increased +12.3% for OTPs but decreased -34.6% for pain. Whereas all states saw a decrease in pain distribution, the Northeast showed a significantly smaller decrease than all other regions. Additionally, the majority of states experienced an increase in distribution for OTPs, and most states demonstrated a relatively stable or increasing number of OTPs, with an +11.5% increase nationally. The number of OTPs per 100K state population ranged from 2.1 in Rhode Island to 0.0 in Wyoming. CONCLUSION AND RELEVANCE: Although methadone distribution for OUD was increasing in the United States, the pronounced regional disparities identified warrant further consideration to improve patient access to this evidence-based pharmacotherapy, particularly in the Midwest and West regions. Greater implementation of telehealth and involvement of primary care into opioid treatment practice offer possible solutions to eliminating geographical treatment barriers.


Assuntos
Buprenorfina , Transtornos Relacionados ao Uso de Opioides , Telemedicina , Analgésicos Opioides/uso terapêutico , Buprenorfina/uso terapêutico , Humanos , Metadona/uso terapêutico , Tratamento de Substituição de Opiáceos , Transtornos Relacionados ao Uso de Opioides/tratamento farmacológico , Transtornos Relacionados ao Uso de Opioides/epidemiologia , Dor/tratamento farmacológico , Estados Unidos/epidemiologia
4.
Am J Hum Biol ; 31(4): e23272, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31184412

RESUMO

OBJECTIVES: Within the Developmental Origins of Adult Disease (DOHaD) model, early life environmental exposures can confer a long-term legacy on human health. This mechanism may be adaptive or maladaptive depending on lifestyle circumstances. This article examines the role of first trimester UV-exposure on late-life vitamin D levels, and potentially related adaptive and maladaptive phenotypes (height and osteoporosis respectively). METHODS: Six hundred and forty nine subjects were examined for vitamin D2 and D3 (HPLC) and height (stadiometer). Osteoporosis was assessed with an extensive medical history questionnaire. RESULTS: Solar irradiance over the first 90 days postconception correlated positively with late-life vitamin D3 (R2 = .0140; P = .0082; ß = .1075), but not vitamin D2 levels. It also correlated positively with female adult height (R2 = .170; P = .0103; ß = .1291) and negatively with the occurrence of female osteoporosis (P = .0495). All data were adjusted for age and gender as appropriate (unadjusted data also provided). From a contemporary perspective, vitamin D levels varied significantly according to season of blood sampling as might be predicted (P = .0009). CONCLUSIONS: Increased solar irradiance/UV exposure during the first trimester of pregnancy calibrates adult vitamin D metabolism, which is an important hormone in maintaining calcium balance. This may explain how very early lifecycle UV exposure can influence skeletal development (adult height) and modify risk for the skeletal degenerative disorder osteoporosis. The data demonstrate humans are tuned to the world (exposome) in ways we have not yet fully considered, and which are entrained at the earliest phase of the lifecycle.


Assuntos
Estatura , Homeostase , Osteoporose/epidemiologia , Fenótipo , Primeiro Trimestre da Gravidez/efeitos da radiação , Raios Ultravioleta/efeitos adversos , Vitamina D/sangue , 25-Hidroxivitamina D 2/sangue , Idoso , Calcifediol/sangue , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , New South Wales/epidemiologia , Osteoporose/etiologia , Gravidez
5.
Am J Hum Biol ; 30(5): e23166, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30198140

RESUMO

OBJECTIVES: The purpose of this study was (1) to elucidate any reciprocal seasonal relationship that might exist between red cell folate (RCF) and serum vitamin D3 Levels; (2) to explore whether folate-related gene variants that influence/alter DNA-thymidylate and methyl group biosynthesis modify any associations detected in objective 1; and (3) to consider whether these processes might influence reproductive success consistent with the "folate-vitamin D-UV hypothesis of skin pigmentation" evolutionary model. METHODS: A large (n = 649) Australian cross-sectional study population was examined. Polymerase chain reaction (PCR)/Restriction fragment length polymorphism (RFLP) analysis was used to genotype C677T-MTHFR, C1420T-SHMT, T401C-MTHFD and 2R > 3R-TS. RCF was measured by chemiluminescent immunoassay and vitamin D2 and D3 by HPLC. RESULTS: RCF and photosynthesized vitamin D3 , but not RCF and dietary vitamin D2 , exhibit a significant reciprocal association in spring and summer. Three folate genes (C677T-MTHFR, C1420T-SHMT, and 2R > 3R-TS) strengthen this effect in spring, and another (T401C-MTHFD) in summer. Effects are seasonal, and do not occur over the whole year. CONCLUSIONS: Findings are consistent with what might be required for the "folate-vitamin D-UV hypothesis of skin pigmentation" model. It suggests genetic influence in provision of one-carbon units by 5,10-methylene-H4 folate, may be an important factor in what appears to be a clear seasonal relationship between vitamin D3 and folate status.


Assuntos
Ácido Fólico/sangue , Vitamina D/sangue , Vitaminas/sangue , Austrália , Colecalciferol/sangue , Colecalciferol/química , Estudos Transversais , Ergocalciferóis/sangue , Ergocalciferóis/química , Eritrócitos/química , Feminino , Ácido Fólico/genética , Humanos , Masculino , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Estações do Ano , Soro/química , Vitamina D/genética , Vitaminas/genética
6.
Nutr Rev ; 76(7): 512-525, 2018 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-29718444

RESUMO

This review explores contemporary ideas about the relationship between light exposure and vitamin biology. Nutritional biochemistry has long recognized the relationship between vitamins A and D and light exposure, but in recent years other vitamins have also been implicated in photoresponsive biological mechanisms that influence health, well-being, and even evolutionary processes. Interactions between light and vitamins can modify genotype-phenotype relationships across the life cycle, providing a basis for interesting new explanations relevant to wide aspects of human biology. This review examines both well-established and emerging ideas about vitamin photobiology in the context of the following: (1) light responsiveness of vitamin D (photosynthesized in skin), vitamin A (linked to vision), and vitamin B3 (needed to repair genomic damage); (2) vulnerability of folate and vitamins B1, B2, B12, and D to ultraviolet (UV) light (all potentially degraded); (3) protective/filtering actions of carotenoids and vitamins C and E, which act as antioxidants and/or natural sunscreens, against UV light; (4) role of folate, carotenoids, and vitamins A, B3, C, D, and E in UV-related genomic regulation, maintenance, and repair; (5) role of folate and vitamins A, B2, B12, and D in a range of light-signaling and light-transduction pathways; and (6) links between folate and vitamin D and the evolution of UV light-adaptive phenotypes.


Assuntos
Processos Fototróficos , Raios Ultravioleta , Vitaminas/metabolismo , Antioxidantes/metabolismo , Ácido Ascórbico/metabolismo , Carotenoides/metabolismo , Ácido Fólico/metabolismo , Humanos , Niacinamida/metabolismo , Fotobiologia , Vitamina A/metabolismo , Vitamina D/metabolismo , Vitamina E/metabolismo
7.
Am J Hum Biol ; 29(5)2017 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-28432711

RESUMO

OBJECTIVES: The vitamin D receptor (VDR) is a member of the nuclear receptor family of transcription factors. We examined whether degree of VDR gene methylation acts as a molecular adaptation to light exposure. We explored this in the context of photoperiod at conception, recent UV irradiance at 305 nm, and gene-latitude effects. METHODS: Eighty subjects were examined for VDR gene-CpG island methylation density. VDR gene variants were also examined by PCR-RFLP. RESULTS: Photoperiod at conception was significantly positively related to VDR methylation density, explaining 17% of the variance in methylation (r2 = 0.17; P = .001). Within this model, photoperiod at conception and plasma 25(OH)D independently predicted methylation density at the VDR-CpG island. Recent UV exposure at 305 nm led to a fivefold increase in mean methylation density (P = .02). Again, UV exposure and plasma 25(OH)D independently predicted methylation density at the VDR-CpG island. In the presence of the BsmI mutant allele, methylation density was increased (P = .01), and in the presence of the TaqI or FokI mutant allele, methylation density was decreased (P = .007 and .04 respectively). Multivariate modelling suggests plasma 25(OH)D, photoperiod at conception, recent solar irradiance, and VDR genotype combine as independent predictors of methylation at the VDR-CpG island, explaining 34% of the variance in methylation (R2 = 0.34, P < .0001). CONCLUSIONS: Duration of early-life light exposure and strength of recent irradiance, along with latitudinal genetic factors, influence degree of VDR gene methylation consistent with this epigenetic phenomenon being a molecular adaptation to variation in ambient light exposure. Findings contribute to our understanding of human biology.


Assuntos
Metilação de DNA/efeitos da radiação , Polimorfismo Genético , Receptores de Calcitriol/genética , Raios Ultravioleta/efeitos adversos , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Humanos , Masculino , New South Wales
8.
J Sci Food Agric ; 97(11): 3781-3789, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28134433

RESUMO

BACKGROUND: Barramundi minced muscle with salt 10 g kg-1 and 20 g kg-1 added is gelled by different combinations of pressurisation (300, 400 and 500 MPa at 4 °C for 10 min), cooking (0.1 MPa, 90 °C for 30 min) and setting (0.1 MPa, 50 °C for 2 h) to improve mechanical properties of barramundi gels and reduce salt added to barramundi gels. RESULTS: At the low salt concentration of 10 g kg-1 , pressurisation prior to cooking (P-C) treatment induced barramundi gels with comparable mechanical properties and water-holding capacity to those of conventional heat induced (HI) gels with 20 g kg-1 added salt. At salt concentration of 20 g kg-1 , pressurisation prior to setting (P-S) and P-C gels exhibited higher mechanical properties and water-holding capacity as compared to HI gels. Scanning electron microscopy images showed a smooth and dense microstructure of P-C and P-S gels whereas the microstructure of HI gels is rough and less compact. CONCLUSIONS: P-C treatment can reduce salt concentration added to barramundi gels to 10 g kg-1 . P-S and P-C treatment can result in higher mechanical and functional properties of barramundi gels at conventional salt concentration (20 g kg-1 ) as compared to HI gels. © 2017 Society of Chemical Industry.


Assuntos
Culinária/métodos , Produtos Pesqueiros/análise , Manipulação de Alimentos/métodos , Músculo Esquelético/química , Animais , Culinária/instrumentação , Géis/análise , Perciformes , Pressão , Cloreto de Sódio/análise , Temperatura
9.
Am J Hum Biol ; 29(2)2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27771938

RESUMO

OBJECTIVES: The purpose of this study was to examine whether UV exposure alters folate status according to C677T-MTHFR genotype, and to consider the relevance of this to human health and the evolutionary model of skin pigmentation. METHODS: Total Ozone Mapping Spectrometer (TOMS) satellite data were used to examine surface UV-irradiance, as a marker of UV exposure, in a large (n = 649) Australian cross-sectional study population. PCR/RFLP analysis was used to genotype C677T-MTHFR. RESULTS: Overall, cumulative UV-irradiance (42 and 120 days pre-clinic) was significantly negatively related to red cell folate (RCF) levels. When the cohort was stratified by MTHFR-C677T genotype, the relationship between UV-irradiance (42 days pre-clinic) and RCF remained significant only in the cohorts containing carriers of the T allele. Statistically significant z-score statistics and interaction terms from genotype and UV-irradiance (p-interaction) demonstrated that genotype did modify the effect of UV-irradiance on RCF, with the largest effect of UV being demonstrated in the 677TT-MTHFR subjects. CONCLUSIONS: Data provide strong evidence that surface UV-irradiance reduces long-term systemic folate levels, and that this is influenced by the C677T-MTHFR gene variant. We speculate this effect may be due to 677TT-MTHFR individuals containing more 5,10CH2 -H4 PteGlu, and that this folate form may be particularly UV labile. Since UV-irradiance lowers RCF in an MTHFR genotype-specific way, there are likely implications for human health and the evolution of skin pigmentation.


Assuntos
Ácido Fólico/metabolismo , Raios Ultravioleta/efeitos adversos , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Ácido Fólico/efeitos da radiação , Genótipo , Humanos , Masculino , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Metilenotetra-Hidrofolato Redutase (NADPH2)/metabolismo , New South Wales , Nutrigenômica
10.
J Evid Based Complementary Altern Med ; 20(4): 310-22, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25878189

RESUMO

Interest in vitamin D and the VDR gene is increasing as putative roles in human health and evolutionary processes are explored. This review looks beyond the classic biochemistry that links vitamin D to calcium homeostasis; it explores how vitamin D interacts with light in a broader perspective than simple skin photosynthesis. It examines how the vitamin influences circadian rhythm, and how it may have helped drive the evolution of skin pigmentation. To this end, the nutrient-nutrient relationship with folate is also explored. The VDR gene is additionally examined as a factor in the evolutionary selection of skin depigmentation at higher latitudes to allow vitamin D synthesis. Evidence is given to show that VDR polymorphisms exhibit a latitudinal gradient in allele prevalence consistent with such a paradigm. Overall, the review examines new evo-devo ideas that link light-sensitive vitamins to human health/phenotype, both within and across the lifecycle.


Assuntos
Vitamina D/metabolismo , Animais , Cálcio/metabolismo , Humanos , Polimorfismo Genético , Receptores de Calcitriol/genética , Receptores de Calcitriol/metabolismo , Pigmentação da Pele/efeitos da radiação
11.
Evol Med Public Health ; 2014(1): 69-91, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24699387

RESUMO

BACKGROUND AND OBJECTIVES: Vitamin D and folate are highly UV sensitive, and critical for maintaining health throughout the lifecycle. This study examines whether solar irradiance during the first trimester of pregnancy influences vitamin D receptor (VDR) and nuclear folate gene variant occurrence, and whether affected genes influence late-life biochemical/clinical phenotypes. METHODOLOGY: 228 subjects were examined for periconceptional exposure to solar irradiance, variation in vitamin D/folate genes (polymerase chain reaction (PCR)), dietary intake (food frequency questionnaire (FFQ)) and important adult biochemical/clinical phenotypes. RESULTS: Periconceptional solar irradiance was associated with VDR-BsmI (P = 0.0008(wk7)), TaqI (P = 0.0014(wk7)) and EcoRV (P = 0.0030(wk6)) variant occurrence between post-conceptional weeks 6-8, a period when ossification begins. Similar effects were detected for other VDR gene polymorphisms. Periconceptional solar irradiance was also associated with 19 bp del-DHFR (P = 0.0025(wk6)), and to a lesser extent C1420T-SHMT (P = 0.0249(wk6)), a folate-critical time during embryogenesis. These same genes were associated with several late-life phenotypes: VDR-BsmI, TaqI and ApaI determined the relationship between dietary vitamin D and both insulin (P < 0.0001/BB, 0.0007/tt and 0.0173/AA, respectively) and systolic blood pressure (P = 0.0290/Bb, 0.0299/Tt and 0.0412/AA, respectively), making them important early and late in the lifecycle. While these and other phenotype associations were found for the VDR variants, folate polymorphism associations in later-life were limited to C1420T-SHMT (P = 0.0037 and 0.0297 for fasting blood glucose and HbA1c levels, respectively). We additionally report nutrient-gene relationships with body mass index, thiol/folate metabolome, cognition, depression and hypertension. Furthermore, photoperiod at conception influenced occurrence of VDR-Tru9I and 2R3R-TS genotypes (P = 0.0120 and 0.0360, respectively). CONCLUSIONS AND IMPLICATIONS: Findings identify environmental and nutritional agents that may interact to modify gene-phenotype relationships across the lifecycle, offering new insight into human ecology. This includes factors related to both disease aetiology and the evolution of skin pigmentation.

12.
J Nutrigenet Nutrigenomics ; 7(4-6): 264-73, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25969372

RESUMO

BACKGROUND AND AIMS: Circulating microRNAs (miRNAs) are linked to disease and are potential biomarkers. Vitamin D may modulate miRNA profiles, and vitamin D status has been linked to risk of disease, including cardiovascular disease and cancers. We hypothesise that genotypic variance influences these relationships. We examined the correlations between vitamin D intake and circulating levels of the miRNAs let-7a/b, and the involvement of two common vitamin D receptor (VDR) polymorphisms, BsmI and ApaI. METHODS: Two hundred participants completed food frequency and supplement questionnaires, and were assayed for circulating let-7b expression by qPCR. Polymorphisms were detected using restriction fragment length polymorphism-PCR. RESULTS: let-7b expression negatively correlated with vitamin D intake (rs=-0.20, p=0.005). The magnitude and direction of correlation were maintained in the presence of the BsmI restriction site (rs=-0.27, p=0.0005). However, in the absence of BsmI restriction site, the direction of the correlation was reversed (rs=+0.319, p=0.0497). These correlations were significantly different (z-score=2.64, p=0.0085). The correlation between vitamin D intake and let-7a was only significant in those without the ApaI restriction site. CONCLUSIONS: The correlation between vitamin D intake and let-7a/b expression in this cohort varies with VDR genotype. This study highlights the importance of considering underlying genotypic variance in miRNA expression studies and in nutritional epigenetics generally.


Assuntos
MicroRNAs/sangue , MicroRNAs/genética , Receptores de Calcitriol/genética , Vitamina D/administração & dosagem , Vitamina D/sangue , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/sangue , Envelhecimento/genética , Estudos de Coortes , Feminino , Expressão Gênica , Genótipo , Humanos , Masculino , Nutrigenômica , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição
13.
Med Hypotheses ; 79(2): 210-5, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22608858

RESUMO

Folate, a key periconceptional nutrient, is ultraviolet light (UV-R) sensitive. We therefore hypothesise that a relationship exists between sunspot activity, a proxy for total solar irradiance (particularly UV-R) reaching Earth, and the occurrence of folate-sensitive, epigenomic-related neonatal genotypes during the first trimester of pregnancy. Limited data is provided to support the hypothesis that the solar cycle predicts folate-related human embryo loss: 379 neonates born at latitude 54°N between 1998 and 2000 were examined for three folate-sensitive, epigenome-related polymorphisms, with solar activity for trimester one accessed via the Royal Greenwich Observatory-US Air force/National Oceanic and Atmospheric Administration Sunspot Database (34,110 total observation days). Logistic regression showed solar activity predicts C677T-methylenetetrahydrofolate reductase (C677T-MTHFR) and A66G-methionine synthase reductase (A66G-MSR) genotype at discrete phases of trimester one. Total and maximal sunspot activity predicts C677T-MTHFR genotype for days 31-60 of trimester one (p=0.0181 and 0.0366, respectively) and A66G-MSR genotype for days 61-90 of trimester one (p=0.0072 and 0.0105, respectively). Loss of UV-R sensitive folate associated with the sunspot cycle might therefore interact with variant folate genes to perturb DNA methylation and/or elaboration of the primary base sequence (thymidylate synthesis), as well as increase embryo-toxic homocysteine. We hypothesise that this may influence embryo viability leading to 677CC-MTHFR and 66GG-MSR embryo loss at times of increased solar activity. This provides an interesting and plausible link between well recognised 'folate gene originated developmental disorders' and 'solar activity/seasonality modulated developmental disorders'.


Assuntos
Clima , Perda do Embrião/epidemiologia , Perda do Embrião/genética , Ácido Fólico/genética , Predisposição Genética para Doença/genética , Primeiro Trimestre da Gravidez/genética , Energia Solar , Feminino , Genótipo , Humanos , Modelos Biológicos , Polimorfismo de Nucleotídeo Único/genética , Gravidez , Prevalência , Reino Unido/epidemiologia
14.
Arch Dermatol Res ; 302(7): 539-44, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20204654

RESUMO

Imiquimod 3.75% cream is a topical formulation of imiquimod intended for daily application to treat actinic keratoses of the entire face or balding scalp. The objective of the study was to characterize serum imiquimod and metabolite pharmacokinetics. Nineteen subjects with actinic keratoses applied two packets of imiquimod 3.75% cream (18.75 mg imiquimod total) once daily for 21 days to a treatment area approximately 200 cm(2) in size on the face and/or balding scalp. Blood samples were obtained prior to application of doses 1, 7, 14 and 21, and at selected timepoints after application of doses 1 and 21. After multiple dosing (day 21) serum imiquimod mean C (max) was 0.323 (standard deviation 0.159) ng/mL, mean AUC(0-24) 5.974 (3.088) ng h/mL, and mean T(1/2) 29.3 (17.0) h. Steady-state was achieved by day 14; multiple dose accumulation ratios were 2.8 based on imiquimod C (max) and 3.9 based on AUC. Serum concentrations of imiquimod metabolites were only sporadically quantifiable in three subjects. One subject discontinued from study for adverse events of body aches and fatigue that were attributed to study drug. Treatment-related adverse events occurred in 42.1% (8/19) of the subjects. Systemic imiquimod exposure, as reflected by serum drug concentration, was low after daily application of two packets of imiquimod 3.75% cream for 21 days. Steady state was achieved by day 14, and the observed half-life of approximately 29 h supports daily dosing of the product.


Assuntos
Aminoquinolinas/farmacocinética , Face/patologia , Ceratose Actínica/tratamento farmacológico , Couro Cabeludo/patologia , Pele/efeitos dos fármacos , Idoso , Idoso de 80 Anos ou mais , Alopecia , Aminoquinolinas/sangue , Feminino , Meia-Vida , Humanos , Imiquimode , Ceratose Actínica/sangue , Ceratose Actínica/patologia , Ceratose Actínica/fisiopatologia , Masculino , Pessoa de Meia-Idade , Pele/metabolismo , Pele/patologia
15.
J Exp Biol ; 205(Pt 4): 539-47, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11893768

RESUMO

The behaviour of clamping the shell against the substratum may play an important role in the limpet adhesion mechanism because friction generated by this behaviour resists dislodgement by shear forces. This paper describes the development of an apparatus to analyse limpet clamping activity in relation to known forces, including simulated wave activity and predator attack. The results show that Cellana tramoserica clamps its shell in a closely regulated manner consistent with an active role in the limpet adhesion mechanism. Limpets clamped sharply for several seconds in response to single disturbances such as tapping the shell. In response to more continuous disturbance simulating a concerted predator attack, limpets clamped tightly for several minutes. In response to lifting forces applied to the shell, limpets clamped at a set proportion of the lifting force, even if the lift force was a highly dynamic wave profile. This behaviour has implications for numerical models that attempt to describe limpet adhesion because it shows that limpets cannot be represented by a simple mechanical analogue and that the clamping behaviour must be accounted for if useful predictions are to be drawn.


Assuntos
Comportamento Animal/fisiologia , Moluscos/fisiologia , Adaptação Fisiológica , Animais , Adesão Celular/fisiologia , Desenho de Equipamento/instrumentação , Fricção , Modelos Biológicos , Pressão , Estresse Mecânico , Movimentos da Água
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