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1.
J Am Chem Soc ; 146(12): 8618-8629, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38471106

RESUMO

Atomically dispersed first-row transition metals embedded in nitrogen-doped carbon materials (M-N-C) show promising performance in catalytic hydrogenation but are less well-studied for reactions with more complex mechanisms, such as hydrogenolysis. Their ability to catalyze selective C-O bond cleavage of oxygenated hydrocarbons such as aryl alcohols and ethers is enhanced with the participation of ligands directly bound to the metal ion as well as longer-range contributions from the support. In this article, we describe how Fe-N-C catalysts with well-defined local structures for the Fe sites catalyze C-O bond hydrogenolysis. The reaction is facilitated by the N-C support. According to spectroscopic analyses, the as-synthesized catalysts contain mostly pentacoordinated FeIII sites, with four in-plane nitrogen donor ligands and one axial hydroxyl ligand. In the presence of 20 bar of H2 at 170-230 °C, the hydroxyl ligand is lost when N4FeIIIOH is reduced to N4FeII, assisted by the H2 chemisorbed on the support. When an alcohol binds to the tetracoordinated FeII sites, homolytic cleavage of the O-H bond is accompanied by reoxidation to FeIII and H atom transfer to the support. The role of the N-C support in catalytic hydrogenolysis is analogous to the behavior of chemically and redox-non-innocent ligands in molecular catalysts based on first-row transition metal ions and enhances the ability of M-N-Cs to achieve the types of multistep activations of strong bonds needed to upgrade renewable and recycled feedstocks.

2.
J Hand Ther ; 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38320939

RESUMO

BACKGROUND: Upper extremity musculoskeletal injuries are common with active-duty Army Soldiers and result in increased limited duty days. Patient satisfaction and surgery rates improve with direct access to occupational therapy in the civilian community. PURPOSE: Examine the amount of time from initial evaluation following an upper extremity musculoskeletal injury (MSKI) to return to full duty plus occupational therapy (OT) utilization in Army Soldiers. STUDY DESIGN: Retrospective observational. METHODS: Electronic health records and profiles from 18,206 US active-duty Army soldiers with MSKI and OT evaluation between 2017-2018 were examined. Repeated measures generalized estimating equations provided the rate ratios (RRs) for OT healthcare utilization (total number of OT evaluations and treatment visits) by days to first OT evaluation and limited duty profile (total days on profile). RESULTS: Soldiers were on average 32.0 (SD = 8.9) y/o, predominantly senior enlisted (45.7%), white (58.0%), male (81.4%), 10.0 (SD = 8.4) years of service, and high school or less educated (51.3%). There were 22,617 UE MSKIs with an OT evaluation and 4936 UE MSKIs with profiles. Compared with UE MSKIs with an OT evaluation on the same day, there was a significant increase in rates of OT utilization for 1-7 days (RR: 1.4, 95% CI: 1.3, 1.5), 8-14 days (RR: 1.3, 95% CI: 1.2, 1.4), 15-30 days (RR: 1.4, 95% CI: 1.3, 1.5), 31-60 days (RR: 1.5, 95% CI: 1.4, 1.6), and +60 days later (RR: 1.6, 95% CI: 1.5, 1.7). Similar differences in rates for limited duty profiles were found. CONCLUSION: A greater number of days between diagnosis of UE MSKI and OT evaluation results in greater rates of OT utilization and longer temporary profile. Results suggest that earlier intervention by OT may decrease recovery and healthcare utilization of soldiers.

3.
Retina ; 43(5): 802-807, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-36728866

RESUMO

PURPOSE: To evaluate the association of posterior vitreous opacities (PVOs) on optical coherence tomography with retinal tears identified on examination in patients with acute, symptomatic posterior vitreous detachment (PVD). METHODS: Data were retrospectively collected from the medical records of 388 patients with acute, symptomatic PVD between January 1, 2021, and June 30, 2021. Included patients had received a primary diagnosis of PVD and presented with flashes and/or floaters. Optical coherence tomography scans were reviewed by two separate readers for the presence of PVOs. The primary outcome was the presence of retinal tear on fundus photograph and on examination. RESULTS: Of 388 patients who presented with acute PVD symptoms, 90 (23.2%) were found to have a retinal tear on dilated fundus examination. Among these patients, 78 (86.7%) were found to have PVOs on optical coherence tomography. Statistical analysis demonstrated a significant relationship between the presence of PVOs and retinal tear ( P < 0.01). The sensitivity and specificity of this finding was 86.7% and 72.5%, respectively. Further analysis included area under the curve from receiver operating characteristic curve which was found to be 0.80. CONCLUSION: The presence of PVOs on optical coherence tomography is suggestive of a retinal tear in patients with acute, symptomatic PVD.


Assuntos
Descolamento Retiniano , Perfurações Retinianas , Descolamento do Vítreo , Humanos , Perfurações Retinianas/diagnóstico , Descolamento do Vítreo/diagnóstico , Estudos Retrospectivos , Tomografia de Coerência Óptica/métodos , Corpo Vítreo/diagnóstico por imagem , Transtornos da Visão , Descolamento Retiniano/diagnóstico
4.
Angew Chem Int Ed Engl ; 62(15): e202218770, 2023 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-36789791

RESUMO

Possible routes for intra-cluster bond formation (ICBF) in protonated serine dimers have been studied. We found no evidence of ICBF following low energy collision-induced dissociation (in correspondence with previous works), however, we do observe clear evidence for ICBF following photon absorption in the 4.6-14 eV range. Moreover, the comparison of photon-induced dissociation measurements of the protonated serine dimer to those of a protonated serine dipeptide provides evidence that ICBF, in this case, involves peptide bond formation (PBF). The experimental results are supported by ab initio molecular dynamics and exploration of several excited state potential energy surfaces, unraveling a pathway for PBF following photon absorption. The combination of experiments and theory provides insight into the PBF mechanisms in clusters of amino acids, and reveals the importance of electronic excited states reached upon UV/VUV light excitation.

5.
Am J Epidemiol ; 190(4): 600-610, 2021 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-33521821

RESUMO

Fetal exposure to elevated androgens is thought to contribute to autism spectrum disorder (ASD) risk. However, data rely heavily on in utero androgens measurements, which also reflect fetal secretions. Thus, in utero hyperandrogenemia might indicate adverse autism-related neurogenesis that has already occurred affecting fetal androgen homeostasis, rather than being a cause of the disorder. Associations between maternal androgen-related conditions and ASD could more directly implicate androgens' etiological role. We examined the association between maternal hyperandrogenemia-related conditions, focusing primarily on polycystic ovarian syndrome (PCOS), and progeny ASD, in an Israeli cohort of 437,222 children born in 1999-2013. Odds ratios and 95% confidence intervals were estimated using generalized estimating equations. Multiple mediation analyses using natural effect models were conducted to evaluate combined mediation of the PCOS effect by androgen-related cardiovascular, metabolic, and fertility factors. Results indicated that children of mothers with PCOS had higher ASD odds compared with children of mothers without PCOS (odds ratio = 1.42, 95% confidence interval: 1.24,1.64), and this effect was only partly mediated by the factors considered. Elevated odds were also observed for other hyperandrogenemia-related conditions. Findings provide support for direct involvement of maternal hyperandrogenemia in ASD etiology. Alternatively, findings might reflect shared genetic and/or environmental factors independently affecting maternal androgen homeostasis and fetal neurodevelopment.


Assuntos
Androgênios/sangue , Transtorno do Espectro Autista/epidemiologia , Doenças Cardiovasculares/complicações , Fertilidade/fisiologia , Doenças Metabólicas/complicações , Mães/estatística & dados numéricos , Efeitos Tardios da Exposição Pré-Natal , Adulto , Transtorno do Espectro Autista/sangue , Transtorno do Espectro Autista/etiologia , Doenças Cardiovasculares/epidemiologia , Pré-Escolar , Feminino , Humanos , Incidência , Masculino , Doenças Metabólicas/epidemiologia , Razão de Chances , Gravidez , Estudos Retrospectivos , Medição de Risco/métodos , Estados Unidos/epidemiologia , Adulto Jovem
6.
Toxicol Appl Pharmacol ; 419: 115513, 2021 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-33785354

RESUMO

The early characterization of ligands at the dopamine and serotonin transporters, DAT and SERT, respectively, is important for drug discovery, forensic sciences, and drug abuse research. 4-Methyl amphetamine (4-MA) is a good example of an abused drug whose overdose can be fatal. It is a potent substrate at DAT and SERT where its simplest secondary amine (N-methyl 4-MA) retains substrate activity at them. In contrast, N-n-butyl 4-MA is very weak, therefore it was categorized as inactive at these transporters. Here, N-octyl 4-MA and other related compounds were synthesized, and their activities were evaluated at DAT and SERT. To expedite this endeavor, cells expressing DAT or SERT were co-transfected with a voltage-gated Ca2+ channel and, the genetically-encoded Ca2+ sensor, GCaMP6s. Control compounds and the newly synthesized molecules were tested on these cells using an automated multi-well fluorescence plate reader; substrates and inhibitors were identified successfully at DAT and SERT. N-Octyl 4-MA and three bivalent compounds were inhibitors at these transporters. These findings were validated by measuring Ca2+-mobilization using quantitative fluorescence microscopy. The bivalent molecules were the most potent of the series and were further characterized in an uptake-inhibition assay. Compared to cocaine, they showed comparable potency inhibiting uptake at DAT and higher potency at SERT. These observations support a previous hypothesis that amphetamine-related (and, here, N-extended alkyl and) bivalent arylalkylamine molecules are active at monoamine transporters, showing potent activity as reuptake inhibitors, and implicate the involvement of a distant auxiliary binding feature to account for their actions at DAT and SERT.


Assuntos
Técnicas Biossensoriais , Canais de Cálcio/metabolismo , Cálcio/metabolismo , Proteínas da Membrana Plasmática de Transporte de Dopamina/antagonistas & inibidores , Inibidores da Captação de Dopamina/toxicidade , Proteínas de Fluorescência Verde/metabolismo , Metanfetamina/toxicidade , Inibidores Seletivos de Recaptação de Serotonina/toxicidade , Proteínas da Membrana Plasmática de Transporte de Serotonina/efeitos dos fármacos , Canais de Cálcio/genética , Proteínas da Membrana Plasmática de Transporte de Dopamina/genética , Proteínas da Membrana Plasmática de Transporte de Dopamina/metabolismo , Proteínas de Fluorescência Verde/genética , Células HEK293 , Humanos , Metanfetamina/análogos & derivados , Metanfetamina/síntese química , Microscopia de Fluorescência , Estrutura Molecular , Proteínas da Membrana Plasmática de Transporte de Serotonina/genética , Proteínas da Membrana Plasmática de Transporte de Serotonina/metabolismo , Relação Estrutura-Atividade , Fatores de Tempo
7.
J Am Chem Soc ; 142(16): 7514-7523, 2020 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-32233465

RESUMO

Ultrahigh field 27Al{1H} 2D correlation NMR experiments demonstrate that at least two framework Al(IV) sites with hydroxyl groups can exist in acidic zeolite catalysts in their dehydrated and catalytically active states. In addition to the known Al(IV) at the framework bridging acid site (BAS), a new site created by a second tetrahedral Al atom and its hydroxyl group protons in zeolite HZSM-5 is clearly resolved at 35.2 T field strengths, enabled by recently developed series-connected hybrid (SCH) magnet technology. Coupled with computational modeling, extensive 27Al MQMAS experiments at multiple field strengths, and 1H MAS NMR experiments, these data indicate that this second tetrahedrally coordinated Al site (denoted Al(IV)-2) experiences an increased chemical shift and unique quadrupolar parameters relative to the BAS in both dehydrated and hydrated states. These new experimental data, supported by computational and catalytic reaction work, indicate that the second site arises from partially bonded framework (SiO)4-n-Al(OH)n species that significantly increase catalyst reactivity in benzene hydride-transfer and n-hexane cracking reactions. Al(IV)-2 sites result either from framework crystallization defects or from incomplete postsynthetic hydrolysis of a framework Al, prior to the formation of extraframework Al. Populations of this second acidic proton site created by the Al(IV)-2 species are shown to be controlled via postsynthetic catalyst treatments, should be general to different catalyst structures, and significantly enhance catalyst reactivity in the cited probe reactions when they are present. The results herein communicate the highest magnetic field strength data on active zeolite catalyst structures to date and enable for the first time the detection of Al and H association on a dry HZSM-5 catalyst, i.e., under conditions representative of typical end-use processes.

8.
Epidemiology ; 31(3): 409-417, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32251066

RESUMO

BACKGROUND: Maternal thyroid dysfunction is suspected of causing adverse neurodevelopmental effects, but current evidence is inconclusive. Epidemiologic investigations generally suggest an association between maternal thyroid dysfunction and neurodevelopment impairments in progeny, but clinical trials of thyroid treatment during pregnancy reported null effects. To better understand these discrepant findings, we evaluated the association between maternal thyroid conditions and autism spectrum disorder (ASD), including examining the role of gestational thyroid-related hormone concentrations and thyroid medications use. METHODS: Analyses considered 437,222 singleton live births occurring in a large Israeli health fund in 1999-2013, followed through 2016. Thyroid conditions and ASD cases were identified through International Classification of Diseases-9 codes with subsequent validation through review of medical records. Laboratory gestational thyroid hormone measurements were also considered. RESULTS: Children of mothers who ever experienced hypothyroidism had a higher risk of ASD compared with children of mothers without hypothyroidism (adjusted odds ratio [aOR] = 1.26, 95% confidence interval [CI] = 1.12, 1.42). The association with hyperthyroidism was less consistent, but elevated in main analyses (aOR = 1.42, 95% CI = 1.04, 1.94). These associations were not explained by maternal gestational thyroid hormones levels nor mitigated by gestational use of thyroid medications. CONCLUSIONS: Results indicate that maternal thyroid conditions are associated with increased ASD risk in progeny, but suggestively not due to direct effects of thyroid hormones. Instead, factors that influence maternal thyroid function could have etiologic roles in ASD through pathways independent of maternal gestational thyroid hormones and thus be unaffected by medication treatment. Factors known to disrupt thyroid function should be examined for possible involvement in ASD etiology.


Assuntos
Transtorno do Espectro Autista , Hipotireoidismo , Complicações na Gravidez , Efeitos Tardios da Exposição Pré-Natal , Transtorno do Espectro Autista/epidemiologia , Criança , Feminino , Humanos , Hipotireoidismo/tratamento farmacológico , Hipotireoidismo/epidemiologia , Gravidez , Complicações na Gravidez/tratamento farmacológico , Complicações na Gravidez/epidemiologia , Medição de Risco
9.
Environ Sci Technol ; 51(14): 8185-8195, 2017 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-28636816

RESUMO

The mitochondrial genome has long been implicated in age-related disease, but no studies have examined its role in the relationship of long-term fine particle (PM2.5) exposure and DNA methylation age (DNAm-age)-a novel measure of biological age. In this analysis based on 940 observations between 2000 and 2011 from 552 Normative Aging Study participants, we determined the roles of mitochondrial DNA haplogroup variation and mitochondrial genome abundance in the relationship of PM2.5 with DNAm-age. We used the GEOS-chem transport model to estimate address-specific, one-year PM2.5 levels for each participant. DNAm-age and mitochondrial DNA markers were measured from participant blood samples. Nine haplogroups (H, I, J, K, T, U, V, W, and X) were present in the population. In fully adjusted linear mixed-effects models, the association of PM2.5 with DNAm-age (in years) was significantly diminished in carriers of haplogroup V (Pinteraction = 0.01; ß = 0.18, 95%CI: -0.41, 0.78) compared to noncarriers (ß = 1.25, 95%CI: 0.58, 1.93). Mediation analysis estimated that decreases in mitochondrial DNA copy number, a measure of mitochondrial genome abundance, mediated 12% of the association of PM2.5 with DNAm-age. Our data suggests that the mitochondrial genome plays a role in DNAm-age relationships particularly in the context of long-term PM2.5 exposure.


Assuntos
Poluentes Atmosféricos/toxicidade , Metilação de DNA , Genoma Mitocondrial , Material Particulado/toxicidade , Fatores Etários , Idoso , Envelhecimento , Feminino , Humanos , Masculino
10.
J Nat Prod ; 80(2): 261-268, 2017 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-28181807

RESUMO

The chemical investigation of the EtOAc extract of Lobaria orientalis collected in the southwestern part of Central Vietnam led to the isolation of new ß-orcinol depsidones, lobarientalones A and B (1 and 2), and diphenyl ethers, lobariethers A-E (3-7). These types of structures are often reported in different lichen species, but the absolute configuration of the stereogenic acetal center has not been defined. This is the first assessment of the (1S) absolute configuration of the stereogenic acetal center using electronic circular dichroism (ECD) spectroscopic data and by comparison with the ECD data of analogous compounds. Based on the co-occurrence of the depsidones, 1,10-di-O-methylstictic acid (8) and (1-2), and diphenyl ethers (3-7), a plausible biosynthesis route toward 1-8 is proposed.


Assuntos
Depsídeos/isolamento & purificação , Lactonas/isolamento & purificação , Líquens/química , Fenóis/isolamento & purificação , Ascomicetos , Dicroísmo Circular , Depsídeos/química , Lactonas/química , Estrutura Molecular , Fenóis/química , Éteres Fenílicos , Resorcinóis , Vietnã
11.
Adv Pharmacol ; 99: 83-124, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38467490

RESUMO

Synthetic cathinone derivatives comprise a family of psychoactive compounds structurally related to amphetamine. Over the last decade, clandestine chemists have synthesized a consistent stream of innovative cathinone derivatives to outpace governmental regulatory restrictions. Many of these unregulated substances are produced and distributed as designer drugs. Two of the principal chemical scaffolds exploited to expand the synthetic cathinone family are methcathinone and α-pyrrolidinopentiophenone (or α-pyrrolidinovalerophenone, α-PVP). These compounds' main physiological targets are monoamine transporters, where they promote addiction by potentiating dopaminergic neurotransmission. This chapter describes techniques used to study the pharmacodynamic properties of cathinones at monoamine transporters in vitro. Biochemical techniques described include uptake inhibition and release assays in rat brain synaptosomes and in mammalian expression systems. Electrophysiological techniques include current measurements using the voltage clamp technique. We describe a Ca2+ mobilization assay wherein voltage-gated Ca2+ channels function as reporters to study the action of synthetic cathinones at monoamine transporters. We discuss results from systematic structure-activity relationship studies on simple and complex cathinones at monoamine transporters with an emphasis on identifying structural moieties that modulate potency and selectivity at these transporters. Moreover, different profiles of selectivity at monoamine transporters directly predict compounds associated with behavioral and subjective effects within animals and humans. In conclusion, clarification of the structural aspects of compounds which modulate potency and selectivity at monoamine transporters is critical to identify and predict potential addictive drugs. This knowledge may allow prompt allocation of resources toward drugs that represent the greatest threats after drugs are identified by forensic laboratories.


Assuntos
Estimulantes do Sistema Nervoso Central , Catinona Sintética , Ratos , Animais , Humanos , Anfetaminas , Estimulantes do Sistema Nervoso Central/química , Estimulantes do Sistema Nervoso Central/farmacologia , Pirrolidinas/química , Pirrolidinas/metabolismo , Pirrolidinas/farmacologia , Mamíferos/metabolismo
12.
ACS Omega ; 9(17): 19182-19192, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38708195

RESUMO

Lightweight biobased insulation polyurethane (BPU) composite foams with high fire-resistance efficiency are interested in building effective energy and low environmental impact today. This study focuses on manufacturing lightweight BPU from liquefied bamboo polyols and biomass resources, including rice husk and wood flour. Then, they are combined with three flame retardant (FR) additives, such as aluminum diethyl phosphinate, aluminum trihydroxide, and diammonium phosphate, to improve their fire resistance performance. The physicochemical properties, microstructure, thermal stability, mechanical properties, and flame-retardant properties of the BPU composites are characterized to optimize their compromise properties. The results showed that composites with optimized FRs achieved UL94 V-0 and those with nonoptimized FRs reached UL94 HB. The limiting oxygen index exhibited that the fire resistance of BPU composites could increase up to 21-37% within FR additives. In addition, the thermal stability of BPU composites was significantly improved in a temperature range of 300-700 °C and the compressive strength of the BPU composites was also enhanced with the presence of FRs. The scanning electron microscopy observation showed an influence of FRs on the morphology and cell size of the BPU composites. The bio-PU-derived samples in this study showed significantly low thermal conductivity values, demonstrating their remarkable thermal insulation effectiveness.

13.
ACS Chem Neurosci ; 14(14): 2527-2536, 2023 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-37406364

RESUMO

α-Pyrrolidinohexiophenone (α-PHP) is the one-carbon unit α-extended homolog of the better-known and widely abused synthetic cathinone central stimulant α-PVP ("flakka"); both are now U.S. Schedule I controlled substances. Structurally, α-PVP and α-PHP possess a common terminal N-pyrrolidine moiety and differ only with respect to the length of their α-alkyl chain. Using a synaptosomal assay, we previously reported that α-PHP is at least as potent as α-PVP as a dopamine transporter (DAT) reuptake inhibitor. A systematic structure-activity study of synthetic cathinones (e.g., α-PHP) as DAT reuptake inhibitors (i.e., transport blockers), a mechanism thought responsible for their abuse liability, has yet to be conducted. Here, we examined a series of 4-substituted α-PHP analogues and found that, with one exception, all behaved as relatively (28- to >300-fold) selective DAT versus serotonin transporter (SERT) reuptake inhibitors with DAT inhibition potencies of most falling within a very narrow (i.e., <3-fold) range. The 4-CF3 analogue of α-PHP was a confirmed "outlier" in that it was at least 80-fold less potent than the other analogues and displayed reduced (i.e., no) DAT vs SERT selectivity. Consideration of various physicochemical properties of the CF3 group, relative to that of the other substituents involved here, provided relatively little insight. Unlike with DAT-releasing agents, as previously reported by us, a QSAR study was precluded because of the limited range of empirical results (with the exception of the 4-CF3 analogue) for DAT reuptake inhibition.


Assuntos
Proteínas da Membrana Plasmática de Transporte de Dopamina , Catinona Sintética , Proteínas da Membrana Plasmática de Transporte de Dopamina/metabolismo , Pirrolidinas/farmacologia , Pirrolidinas/química , Inibidores da Captação de Dopamina/farmacologia , Inibidores da Captação de Dopamina/química , Relação Estrutura-Atividade , Proteínas da Membrana Plasmática de Transporte de Serotonina , Inibidores Seletivos de Recaptação de Serotonina
14.
Front Pharmacol ; 14: 1101290, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36762110

RESUMO

Certain 4-substituted analogs of 1-(2,5-dimethoxyphenyl)isopropylamine (2,5-DMA) are psychoactive classical hallucinogens or serotonergic psychedelic agents that function as human 5-HT2A (h5-HT2A) serotonin receptor agonists. Activation of a related receptor population, h5-HT2B receptors, has been demonstrated to result in adverse effects including cardiac valvulopathy. We previously published on the binding of several such agents at the two receptor subtypes. We hypothesized that, due to their structural similarity, the 5-HT2A and 5-HT2B receptor affinities of these agents might be related, and that QSAR studies might aid future studies. For a series of 13 compounds, it is demonstrated here that i) their published rat brain 5-HT2 receptor affinities are significantly correlated with their h5-HT2A (r = 0.942) and h5-HT2B (r = 0.916) affinities, ii) as with r5-HT2 receptor affinity, h5-HT2A affinity is correlated with the lipophilicity of the 4-position substituent (r = 0.798), iii) that eight of the ten compounds examined in functional (Ca+2 mobilization in stable cell lines generated expressing the human 5-HT2B receptor using the Flp-In T-REx system) assays acted as h5-HT2B agonists (4-substituent = H, F, Br, I, OCH2CH3, NO2, nC3H7, tC4H9) and two (n-hexyl and benzyl) as antagonists, iv) h5-HT2B affinity but not action was correlated with the lipophilicity of the 4-position substituent (r = 0.750; n = 10). The findings suggest that h5-HT2B receptor affinity, and its relationship to substituent lipophilicity, might be approximated by rat and h5-HT2A affinity but cannot be used as a predictor of h5-HT2B agonist action of 2,5-DMA analogs. Furthermore, given that certain 2,5-DMA analogs are on the clandestine market, their potential to produce cardiac side effects following persistent or chronic use via activation of h5-HT2B receptors should be considered.

15.
Med Sci Sports Exerc ; 55(9): 1533-1539, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37057721

RESUMO

PURPOSE: To determine whether changes in menstruation develop in female trainees during BCT and whether changes in body mass, body composition and/or physical activity are associated with menstrual interruption during BCT. METHODS: Female trainees grouped according to self-reported menstrual status in the 12 months before BCT as having regular cycles (RC; n = 352) or MD ( n = 97) completed height, body mass, and body composition assessments and questionnaires before and after BCT. Fisher's exact test and Mann-Whitney U test were used to compare between-group differences in categorical and continuous variables, respectively. Among RC trainees, odds ratios were calculated to examine the influence of changes in body mass, lean mass, and fat mass on a trainee's likelihood to miss a period during BCT. RESULTS: There were no differences in race, height, body mass, body mass index, or physical activity history at pre-BCT between RC and MD ( P > 0.05). Overall, 86% of trainees experienced changes to menstruation during BCT. RC were more likely than MD to have at least one period during BCT (81% vs 69%, respectively, P = 0.01). Among RC, gaining more body mass and lean mass and losing less fat mass were associated with increased odds of missing a period during BCT. CONCLUSIONS: These findings demonstrate that most female trainees experience menstrual changes during BCT. Menstrual cycle interruptions do not appear to align with loss of body or fat mass.


Assuntos
Menstruação , Militares , Humanos , Feminino , Índice de Massa Corporal , Exercício Físico , Composição Corporal , Ciclo Menstrual
16.
JBMR Plus ; 7(4): e10719, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37065629

RESUMO

Basic combat training (BCT) is a physically rigorous period at the beginning of a soldier's career that induces bone formation in the tibia. Race and sex are determinants of bone properties in young adults but their influences on changes in bone microarchitecture during BCT are unknown. The purpose of this work was to determine the influence of sex and race on changes in bone microarchitecture during BCT. Bone microarchitecture was assessed at the distal tibia via high-resolution peripheral quantitative computed tomography at the beginning and end of 8 weeks of BCT in a multiracial cohort of trainees (552 female, 1053 male; mean ± standard deviation [SD] age = 20.7 ± 3.7 years) of which 25.4% self-identified as black, 19.5% as race other than black or white (other races combined), and 55.1% as white. We used linear regression models to determine whether changes in bone microarchitecture due to BCT differed by race or sex, after adjusting for age, height, weight, physical activity, and tobacco use. We found that trabecular bone density (Tb.BMD), thickness (Tb.Th), and volume (Tb.BV/TV), as well as cortical BMD (Ct.BMD) and thickness (Ct.Th) increased following BCT in both sexes and across racial groups (+0.32% to +1.87%, all p < 0.01). Compared to males, females had greater increases in Tb.BMD (+1.87% versus +1.40%; p = 0.01) and Tb.Th (+0.87% versus +0.58%; p = 0.02), but smaller increases in Ct.BMD (+0.35% versus +0.61%; p < 0.01). Compared to black trainees, white trainees had greater increases in Tb.Th (+0.82% versus +0.61%; p = 0.03). Other races combined and white trainees had greater increases in Ct.BMD than black trainees (+0.56% and + 0.55% versus +0.32%; both p ≤ 0.01). Changes in distal tibial microarchitecture, consistent with adaptive bone formation, occur in trainees of all races and sexes, with modest differences by sex and race. Published 2023. This article is a U.S. Government work and is in the public domain in the USA. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

17.
Mil Med ; 187(7-8): e889-e897, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34279035

RESUMO

INTRODUCTION: Neuromusculoskeletal injuries (NMSKIs) are the primary cause of ambulatory visits, lost duty days, and disability discharges in the U.S. Military. Methods for accurately grouping injury diagnoses are required to allow for surveillance and research identifying risk factors and prevention strategies. The CDC method of grouping these diagnoses includes only the S and T codes (Injury, poisoning, and certain other consequences of external causes) from the ICD-10-CM. However, this does not include the majority of the NMSKI depleting soldier readiness; the M (Disease of the musculoskeletal system and connective tissue) and G (Diseases of the nervous system) codes should be included as these also contain injuries. The goal was to develop a new matrix that would comprehensively capture all NMSKIs experienced by military personnel. This paper details the development of the Occupational Military Neuromusculoskeletal Injury (OMNI) Matrix and characterizes the number and rates of active duty U.S. Army injuries as measured by the OMNI compared to other matrices. MATERIALS AND METHODS: A team of researchers including physical therapists, physician assistants, occupational therapists, physicians, and epidemiologists developed the OMNI. The OMNI utilizes the commonly accepted injury definition inclusive of any anatomical complaint resulting in pain or dysfunction and categorizes injuries from the G, M, S, and T codes. The OMNI follows the CDC's matrix structure with three body region levels, each becoming more specific, and adds two levels called Description of the Injury. Additionally, the OMNI categorizes injuries as Injury Type (Acute, Overuse, Either, or Not Applicable), NMSKI-Type (NMSKI, NMSKI that could be caused by occupational/training tasks, and not an NMSKI), and a miscellaneous category that demarks injuries as Superficial, Blood Vessels, and/or Internal Organs. The different grouping methods in the OMNI provide standardization for many possible injury case definitions. The OMNI allows these injury categories to be included/excluded in a standardized fashion to meet the researchers' scientific questions. To enumerate the number of NMSKI that would be captured by the available matrices, the OMNI, the CDC's matrix, and the U.S. Army Public Health Center's (APHC) Taxonomy of Injuries were applied to active duty Army outpatient population data and all incident NMSKI diagnostic codes entered in electronic medical provider encounters for calendar years 2017 and 2018. RESULTS: Using the OMNI resulted in the capture of over 800,000 more injuries than the CDC's matrix and over 200,000 more than the APHC Taxonomy. The NMSKI rate utilizing the OMNI was 193 per 100 soldier-years in 2017 (892,780 NMSKI) compared to 23 per 100 soldier-years for the CDC's matrix, and 141 per 100 soldier-years for the APHC Taxonomy. CONCLUSION: The OMNI provides an updated standardized method of assessing injuries, particularly in occupational military injury research, that can be utilized for Military Performance Division of injury across many countries and still allow for replication of methods and comparison of results. Additionally, the OMNI has the capacity to capture a greater burden of injury beyond what is captured by other available matrices.


Assuntos
Militares , Sistema Musculoesquelético , Traumatismos Ocupacionais , Humanos , Classificação Internacional de Doenças , Sistema Musculoesquelético/lesões , Traumatismos Ocupacionais/epidemiologia , Traumatismos Ocupacionais/etiologia , Fatores de Risco , Estados Unidos/epidemiologia
18.
ACS Omega ; 7(1): 1003-1013, 2022 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-35036764

RESUMO

The characteristics of aerogel materials such as the low density and large surface area enable them to adsorb large amounts of substances, so they show great potential for application in industrial wastewater treatment. Herein, using a combination of completely environmentally friendly materials such as cellulose nanofibers (CNFs) extracted from the petioles of the nipa palm tree and graphene oxide (GO) fabricated by simple solvent evaporation, a composite aerogel was prepared by a freeze-drying method. The obtained aerogel possessed a light density of 0.0264 g/cm3 and a porosity of more than 98.2%. It was able to withstand a weight as much as 2500 times with the maximum force (1479.5 N) to break up 0.2 g of an aerogel by compression strength testing and was stable in the aquatic environment, enabling it to be reused five times with an adsorption capacity over 90%. The CNF/GO aerogel can recover higher than 85% after 30 consecutive compression recovery cycles, which is convenient for the reusability of this material in wastewater treatments. The obtained aerogel also showed a good interaction between the component phases, a high thermal stability, a 3D network structure combined with thin walls and pores with a large specific surface area. In addition, the aerogel also exhibited a fast adsorption rate for methylene blue (MB) adsorption, a type of waste from the textile industry that pollutes water sources, and it can adsorb more than 99% MB in water in less than 20 min. The excellent adsorption of MB onto the CNF/GO aerogel was driven by electrostatic interactions, which agreed with the pseudo-second-order kinetic model with a correlation coefficient R 2 = 0.9978. The initial results show that the CNF/GO aerogel is a highly durable "green" light material that might be applied in the treatment of domestic organic waste water and is completely recoverable and reusable.

19.
J Expo Sci Environ Epidemiol ; 32(3): 427-433, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34211112

RESUMO

BACKGROUND AND OBJECTIVE: Toenail metal concentrations can be used as an effective biomarker for exposure to environmental toxicants. Typically toenail clippings are measured ex vivo using inductively coupled plasma mass spectrometry (ICP-MS). X-ray fluorescence (XRF) toenail metal measurements done on intact toenails in vivo could be used as an alternative to alleviate some of the disadvantages of ICP-MS. In this study, we assessed the ability to use XRF to measure toenail metal concentrations in real-time without having to clip the toenails (i.e., in vivo) in two occupational settings for exposure assessment of manganese and mercury. MATERIALS AND METHODS: The portable XRF method used a 3-min in vivo measurement of toenails prior to clipping and was assessed against ICP-MS measurement of toenail clippings taken immediately after the XRF measurement and work history for a group of welders (n = 16) assessed for manganese exposure and nail salon workers (n = 10) assessed for mercury exposure. RESULTS AND CONCLUSIONS: We identified that in vivo XRF metal measurements were able to discern exposure to manganese in welders and mercury in nail salon workers. We identified significant positive correlations between ICP-MS of clippings and in vivo XRF measures of both toenail manganese (R = 0.59, p = 0.02) and mercury (R = 0.74, p < 0.001), as well as between in vivo XRF toenail manganese and work history among the welders (R = 0.55, p = 0.03). We identified in vivo XRF detection limits to be 0.5 µg/g for mercury and 2.6 µg/g for manganese. Further work should elucidate differences in the timing of exposure using the in vivo XRF method over toenail clippings and modification of measurement time and x-ray setting to further decrease the detection limit. In vivo portable, XRF measurements can be used to effectively measure toenail Mn and Hg in occupational participants in real-time during study visits and at a fraction of the cost.


Assuntos
Mercúrio , Unhas , Fluorescência , Humanos , Manganês/análise , Mercúrio/análise , Metais/análise , Unhas/química , Espectrometria por Raios X/métodos , Raios X
20.
Inquiry ; 58: 469580211035735, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34595964

RESUMO

The National Institute for Occupational Safety and Health (NIOSH) and several university programs have collaborated on a large effort to expand and improve occupational safety and health content in Wikipedia using a platform developed by Wiki Education. This article describes the initiative, student contributions, and evaluations of this effort by instructors from two universities between 2016 and 2020. The Wiki Education platform allowed instructors to set timelines and track students' progress throughout the semester while students accessed training to best expand health content in Wikipedia. Students chose topics in occupational health based on their interests and by a set of topics deemed as a priority by the "WikiProject Occupational Safety and Health." Students' contributions were peer-reviewed by instructors, NIOSH Wikipedians-in-Residence, and traditional Wikipedians. Students presented their projects in class at the end of the semester. Students from both schools expanded 55 articles, created 8 new articles, and translated 2 articles to Spanish, adding 1270 references; these articles were viewed over 8 million times by May 2020. Feedback received from the implementation suggested that students learned about science communication and digital literacy-providing valuable content on occupational health while reducing misinformation in the public domain. The process of identifying and addressing gaps in occupational health in Wikipedia requires participation and engagement toward improving access to information that otherwise would be restricted to the scientific literature, often behind a paywall. The Wikipedia assignment proved to be an engaging approach for instruction and information literacy. It helped students improve their science communication skills and digital literacy, tools that are likely to be critical for successful communication of science in their future careers.


Assuntos
Saúde Ocupacional , Humanos , Estudantes , Estados Unidos
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