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1.
Geohealth ; 5(11): e2021GH000491, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34849441

RESUMO

With the Artemis III mission scheduled to land humans on the Moon in 2025, work must be done to understand the hazards lunar dust inhalation would pose to humans. In this study, San Carlos olivine was used as an analog of lunar olivine, a common component of lunar dust. Olivine was dissolved in a flow-through apparatus in both simulated lung fluid and 0.1 M HCl (simulated gastric fluid) over a period of approximately 2 weeks at physiological temperature, 37°C. Effluent samples were collected periodically and analyzed for pH, iron, silicon, and magnesium ion concentrations. The dissolution rate data derived from our measurements allow us to estimate that an inhaled 1.0 µm diameter olivine particle would take approximately 24 years to dissolve in the human lungs and approximately 3 weeks to dissolve in gastric fluid. Results revealed that inhaled olivine particles may generate the toxic chemical, hydroxyl radical, for up to 5-6 days in lung fluid. Olivine dissolved in 0.1 M HCl for 2 weeks transformed to an amorphous silica-rich solid plus the ferric iron oxy-hydroxide ferrihydrite. Olivine dissolved in simulated lung fluid shows no detectable change in composition or crystallinity. Equilibrium thermodynamic models indicate that olivine in the human lungs can precipitate secondary minerals with fibrous crystal structures that have the potential to induce detrimental health effects similar to asbestos exposure. Our work indicates that inhaled lunar dust containing olivine can settle in the human lungs for years and could induce long-term potential health effects like that of silicosis.

2.
J Dairy Sci ; 102(4): 3722-3734, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30712934

RESUMO

In dairy production, high fertility contributes to herd profitability by achieving greater production and maintaining short calving intervals. Improved management practices and genetic selection have contributed to reversing negative trends in dairy cow fertility, but further progress is still required. Phenotypes included in current genetic evaluations are largely interval and binary traits calculated from insemination and calving date records. Several indicator traits such as calving, health, variation in body condition score, and longevity traits also apply to genetic improvement of fertility. Several fertility traits are included in the selection indices of many countries, but for improved selection, the development of novel phenotypes that more closely describe the physiology of reproduction and limit management bias could be more effective. Progesterone-based phenotypes can be determined from milk samples to describe the heritable interval from calving to corpus luteum activity, as well as additional measures of cow cyclicity. A fundamental component of artificial insemination practices is the observation of estrus. Novel phenotypes collected on estrous activity could be used to select for cows clearly displaying heat, as those cows are more likely to be inseminated at the right time and therefore have greater fertility performance. On-farm technologies, including in-line milk testing and activity monitors, may allow for phenotyping novel traits on large numbers of animals. Additionally, selection for improved fertility using traditional traits could benefit from refined and accurate recording and implementation of parameters such as pregnancy confirmation and reproductive management strategy, to differentiate embryonic or fetal loss, and to ensure selection for reproductive capability without producer intervention. Opportunities exist to achieve genetic improvement of reproductive efficiency in cattle using novel phenotypes, which is required for long-term sustainability of the dairy cattle population and industry.


Assuntos
Bovinos/genética , Fertilidade/genética , Fenótipo , Seleção Genética , Animais , Bovinos/fisiologia , Corpo Lúteo , Indústria de Laticínios/métodos , Feminino , Inseminação Artificial/veterinária , Lactação , Longevidade , Gravidez , Progesterona , Reprodução/genética
3.
Pediatr Obes ; 13(11): 705-714, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29493105

RESUMO

BACKGROUND: Numerous studies have shown that there are links between obesity, liver fat and the gut microbiome. However, there are mixed results on whether probiotics could impact the gut microbiome and/or help to decrease liver fat and obesity outcomes. OBJECTIVE: This study aimed to determine whether a probiotic supplement (VSL#3® ) intervention altered gut microbiota and/or gut hormones associated with appetite regulation. The secondary aim of this study was to determine whether VSL#3® altered body composition and liver fat and fibrosis. METHODS: We conducted a double-blind, randomized placebo-controlled trial in 19 obese Latino adolescents. The intervention consisted of three packets per day of VSL#3® or a matched placebo for 16 weeks. Pre-intervention and post-intervention measures included gut microbial abundance, gut appetite regulating hormones, anthropometrics, body composition, liver fat and liver fibrosis. We conducted linear models to determine whether there were any significant differences in the changes in these outcomes following VSL#3® intervention. RESULTS: Compared with placebo, adolescents that received VSL#3 had significant increases in total adiposity (%) (+1.7 ± 0.6 vs. -1.3 ± 0.5, p < 0.01) and trunk adiposity (%) (+3.3 ± 0.8 vs. -1.8 ± 0.8, p < 0.01) with no significant effects on liver fat/fibrosis, insulin/glucose, gut microbial abundances or gut hormones. CONCLUSION: VSL#3 supplementation may lead to increased adiposity in obese Latino adolescents with no significant detectable changes in gut microbiota, gut appetite-regulating hormones, liver fat and fibrosis and dietary intake. However, it is important to note that recruitment efforts were terminated early and the sample size fell short of what was planned for this trial.


Assuntos
Fígado Gorduroso/fisiopatologia , Microbioma Gastrointestinal/fisiologia , Obesidade Infantil/terapia , Probióticos/uso terapêutico , Adolescente , Antropometria/métodos , Apetite/fisiologia , Glicemia/análise , Composição Corporal/fisiologia , Criança , Método Duplo-Cego , Feminino , Hispânico ou Latino/estatística & dados numéricos , Humanos , Insulina/sangue , Cirrose Hepática/fisiopatologia , Masculino , Obesidade Infantil/microbiologia , Obesidade Infantil/fisiopatologia , Probióticos/efeitos adversos
4.
Artigo em Inglês | MEDLINE | ID: mdl-29414584

RESUMO

Photodynamic therapy is an alternative form of cancer treatment that meets the desire for a less aggressive approach to the body. It is based on the interaction between a photosensitizer, activating light, and molecular oxygen. This interaction results in a cascade of reactions that leads to localized cell death. Many studies have been conducted to discover an ideal photosensitizer, which aggregates all the desirable characteristics of a potent cell killer and generates minimal side effects. Using Density Functional Theory (DFT) implemented in the program Vienna Ab-initio Simulation Package, new chlorin derivatives with different functional groups were simulated to evaluate the different absorption wavelengths to permit resonant absorption with the incident laser. Gaussian 09 program was used to determine vibrational wave numbers and Natural Bond Orbitals. The chosen drug with the best characteristics for the photosensitizer was a modified model of the original chlorin, which was called as Thiol chlorin. According to our calculations it is stable and is 19.6% more efficient at optical absorption in 708 nm in comparison to the conventional chlorin e6. Vibrational modes, optical and electronic properties were predicted. In conclusion, this study is an attempt to improve the development of new photosensitizer drugs through computational methods that save time and contribute to decrease the numbers of animals for model application.


Assuntos
Modelos Moleculares , Fármacos Fotossensibilizantes/química , Porfirinas/química , Teoria Quântica , Animais , Humanos , Luz , Fotoquimioterapia
5.
Appetite ; 124: 33-42, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-28479407

RESUMO

Despite a substantial amount of animal data linking deficits in memory inhibition to the development of overeating and obesity, few studies have investigated the relevance of memory inhibition to uncontrolled eating in humans. Further, although memory for recent eating has been implicated as an important contributor to satiety and energy intake, the possibility that variations in episodic memory relate to individual differences in food intake control has been largely neglected. To examine these relationships, we recruited ninety-three adult subjects to attend a single lab session where we assessed body composition, dietary intake, memory performance, and eating behaviors (Three Factor Eating Questionnaire). Episodic recall and memory inhibition were assessed using a well-established measure of memory interference (Retrieval Practice Paradigm). Hierarchical regression analyses indicated that memory inhibition was largely unrelated to participants' eating behaviors; however, episodic recall was reliably predicted by restrained vs. uncontrolled eating: recall was positively associated with strategic dieting (ß = 2.45, p = 0.02), avoidance of fatty foods (ß = 3.41, p = 0.004), and cognitive restraint (ß = 1.55, p = 0.04). In contrast, recall was negatively associated with uncontrolled eating (ß = -1.15, p = 0.03) and emotional eating (ß = -2.46, p = 0.04). These findings suggest that episodic memory processing is related to uncontrolled eating in humans. The possibility that deficits in episodic memory may contribute to uncontrolled eating by disrupting memory for recent eating is discussed.


Assuntos
Ingestão de Alimentos/psicologia , Comportamento Alimentar/psicologia , Memória Episódica , Adiposidade , Adolescente , Adulto , Idoso , Composição Corporal , Índice de Massa Corporal , Dieta/psicologia , Dieta Redutora/psicologia , Carboidratos da Dieta/administração & dosagem , Gorduras na Dieta/administração & dosagem , Proteínas Alimentares/administração & dosagem , Açúcares da Dieta/administração & dosagem , Ácidos Graxos/administração & dosagem , Feminino , Comportamentos Relacionados com a Saúde , Humanos , Masculino , Rememoração Mental , Pessoa de Meia-Idade , Avaliação Nutricional , Inquéritos e Questionários , Adulto Jovem
6.
Geohealth ; 1(5): 237-246, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29085918

RESUMO

United States soldiers are returning from the Greater Middle East with respiratory illnesses ranging from new onset asthma to constrictive bronchiolitis. The etiology of the diseases is unknown. A study was conducted to determine the possible role of local mineral dust in the development of abnormal respiratory illnesses in soldiers during and after deployment in Iraq. A dust sample obtained in proximity to a burn pit in Camp Victory, Iraq, (CVD) was characterized both chemically and mineralogically. For comparison, a dust sample from Fort Irwin, California, (FID) was also collected. The ability of the dust samples to generate reactive oxygen species (ROS) was quantified, as well as their ability to generate an inflammatory stress response (ISR) in human lung epithelial cells. Both samples are comprised of common silicate and carbonate minerals and contain heavy metals with concentration ranges expected for mineral dust. The ISR generated by each sample was within the range of inert material with the minimal stress generated associated with the carbonate phases. The findings based on this one sample suggest that the origin of the disease is not driven by the particles ability to generate ROS. However it is likely that particle overload, and associated complications, or endotoxin contribute extensively to pathogenesis.

7.
Sci Rep ; 7: 39754, 2017 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-28059109

RESUMO

The formation of stable radiation damage in crystalline solids often proceeds via complex dynamic annealing processes, involving migration and interaction of ballistically-generated point defects. The dominant dynamic annealing processes, however, remain unknown even for crystalline Si. Here, we use a pulsed ion beam method to study defect dynamics in Si bombarded in the temperature range from -20 to 140 °C with 500 keV Ar ions. Results reveal a defect relaxation time constant of ~10-0.2 ms, which decreases monotonically with increasing temperature. The dynamic annealing rate shows an Arrhenius dependence with two well-defined activation energies of 73 ± 5 meV and 420 ± 10 meV, below and above 60 °C, respectively. Rate theory modeling, bench-marked against this data, suggests a crucial role of both vacancy and interstitial diffusion, with the dynamic annealing rate limited by the migration and interaction of vacancies.

8.
Spectrochim Acta A Mol Biomol Spectrosc ; 169: 95-107, 2016 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-27344520

RESUMO

Theoretical and experimental bands have been assigned for the Fourier Transform Infrared and Raman spectra of the bis(diethyldithiocarbamate)Mn(II) complex, [Mn(DDTC)2]. The calculations have been based on the DFT/B3LYP method, second derivative spectra and band deconvolution analysis. The UV-vis experimental spectra were measured in acetonitrile solution, and the calculated electronic spectrum was obtained using the TD/B3LYP method with 6-311G(d, p) basis set for all atoms. Charge transfer bands and those d-d spin forbidden were assigned in the UV-vis spectrum. The natural bond orbital analysis was carried out using the DFT/B3LYP method and the Mn(II) hybridization leading to the planar geometry of the framework was discussed. Surface enhanced Raman scattering (SERS) was also performed. Mulliken charges of the normal modes were obtained and related to the SERS enhanced bands.

9.
Comput Biol Med ; 75: 151-9, 2016 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-27289538

RESUMO

The present work, involves the simulation of the transport of a vitamin C derivative, Ascorbyl Tetraisopalmitate (ATI), through human skin by molecular dynamics. Percutaneous absorption of the ATI molecule through the infundibulum, an important route of absorption into the hair follicle of the human skin, has been modeled and compared with the stratum corneum membrane. The comparative study was done using molecular dynamics with Martini force field. In infundibulum, a single ATI molecule require more time to penetrate, and the data obtained suggested that a high concentration of ATI molecule accelerated the process of penetration. In conclusion, the ATI molecule was found to have more affinity towards the stratum corneum as compared with the infundibulum, and it followed a straight pathway to penetrate (until 600ns of simulation). In the infundibulum, it showed less affinity, more mobility and followed a lateral pathway. Thus, this work contributes to a better understanding of the different molecular interactions during percutaneous absorption of active molecules in these two different types of biological membranes.


Assuntos
Ácido Ascórbico/análogos & derivados , Membrana Celular/química , Simulação de Dinâmica Molecular , Ácido Ascórbico/química , Ácido Ascórbico/farmacocinética , Membrana Celular/metabolismo , Folículo Piloso/química , Folículo Piloso/metabolismo , Humanos , Absorção Cutânea
10.
Actas Urol Esp ; 40(8): 523-8, 2016 Oct.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-26992850

RESUMO

INTRODUCTION: Indicators show the presence of a phenomenon and its intensity. They assess the level of quality care and identify potential situations for improvement. Our objective is to assess the 2013 and 2014 quality care indicators of our department's kidney transplantation area. MATERIAL AND METHOD: For 2013 and 2014, we reviewed 88 and 106 kidney transplants and 47 and 66 extractions. We evaluated the quality care indicators developed by the Spanish Urological Association, analysing the results with the SPSS v 21.0 programme. RESULTS: The mean cold ischaemia time (CIT) was 14.96hours in 2013 and 18.07hours in 2014. The CIT was ≤18h in 53% and 56% of cadaveric donor kidneys in 2013 and 2014, respectively. The rate of relevant early onset urinary fistulae was 1.14% and 2.83% for each year. The rate of early transplantectomy due to a vascular complication was 3.41% and 2.83% for 2013 and 2014, respectively. Overall patient survival at 1 year was 100% for both periods, and graft survival at 1 year was 95% and 94.34% for 2013 and 2014, respectively. The rate of living-donor transplantation was 14.77% and 17.92%, and 92.31% and 68.42% of the living-donor extractions were laparoscopic for 2013 and 2014, respectively. Resident medical interns were the first surgeon in 6.67% and 12.64% of the transplantations and in 55.88% and 19.14% of the cadaveric extractions during 2013 and 2014, respectively. CONCLUSIONS: During the evaluated period, all quality care standards in kidney transplantation were met, except for CIT in both years and resident medical intern participation in kidney implantation in 2013. This analysis promotes improvements in quality care, highlighting weak spots that need work.


Assuntos
Transplante de Rim/normas , Indicadores de Qualidade em Assistência à Saúde , Humanos , Sociedades Médicas , Espanha , Urologia
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