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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.
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
9.
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.

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
11.
Clin Oncol (R Coll Radiol) ; 28(6): 386-92, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26782838

RESUMO

AIMS: To report the long-term toxicities and sexual quality of life of a once-weekly hypofractionated radiation therapy schedule for low-risk prostate cancer. MATERIALS AND METHODS: A multi-institutional phase II trial was conducted, using a three-dimensional conformal radiation therapy (3D-CRT) approach for low-risk prostate cancer (T1a-T2a, Gleason ≤ 6 and prostate-specific antigen ≤ 10 ng/ml). Forty-five Gray (Gy) were delivered in nine fractions of 5 Gy given on a weekly basis. Acute and late genitourinary and gastrointestinal toxicities were graded according to the Radiation Therapy Oncology Group toxicity scale. Sexual function and sexual bother were assessed with the Expanded Prostate Cancer Index Composite (EPIC) questionnaire. RESULTS: Between March 2006 and August 2008, 80 patients were treated, with a median age of 69 years (interquartile range 64-72). The median follow-up was 83 months (interquartile range 73-85 months). At 7 years, overall survival was 88%. No patients died of prostate cancer. Cumulative grade ≥2 genitourinary and gastrointestinal late toxicity was reported for 31.3% and 30% of our patients, respectively. Cumulative grade ≥3 genitourinary and gastrointestinal late toxicity was seen in 3.8% and 12.5% of cases, respectively. Late genitourinary grade 2 toxicity was correlated with the occurrence of acute genitourinary grade 2 toxicity (P = 0.006). The occurrence of late gastrointestinal toxicity was not correlated with acute gastrointestinal toxicity. Pre-treatment EPIC sexual function was low (37.5%) and the mean EPIC sexual function score at 7 years after treatment was 14%. On the other hand, pre-treatment EPIC sexual bother reached 80.5%, meaning little bother, and remained stable during follow-up. CONCLUSIONS: Once-weekly 3D-CRT leads to excellent biochemical disease-free survival and acceptable toxicities. Pre-treatment EPIC sexual function dropped by 42% at 5 years of follow-up. This functional deficit did not bother patients, possibly due to the already low sexual function at baseline.


Assuntos
Adenocarcinoma/radioterapia , Gastroenteropatias/etiologia , Doenças Urogenitais Masculinas/etiologia , Neoplasias da Próstata/radioterapia , Lesões por Radiação/etiologia , Radioterapia Conformacional/efeitos adversos , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Qualidade de Vida , Hipofracionamento da Dose de Radiação , Fatores de Risco , Inquéritos e Questionários , Taxa de Sobrevida , Resultado do Tratamento
12.
J Photochem Photobiol B ; 153: 51-8, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26398811

RESUMO

A new approach to the study of the effects on human skin of mycosporine-like amino acids (MAAs) and gadusol (Gad) incorporated in polymer gel is proposed in this work. The depth profile and photoprotector effects of Pluronic F127® gels containing each of the natural actives were evaluated by in vivo confocal Raman spectroscopy aiming at the analysis of the biochemical changes on human skin. Hierarchical cluster analysis (HCA) showed that the data corresponding to different depths of the skin, from surface to 4 µm, and from 6 to 16 µm, remained in the same cluster. In vivo Raman spectra, classified into five different layers of epidermis according to their similarities, indicated that the amount of Gad gel increased by about 26% in the outermost layer of the stratum corneum (SC) and that MAAs gel at 2 µm depth was 103.4% higher than in the outermost layer of the SC. Variations in the SC of urocanic acid at 1490-1515 cm(-1) and 1652 cm(-1) and histidine at 1318 cm(-1) were calculated, before and after UV exposure with or without gels. With the application of gels the vibrational modes that correspond to lipids in trans conformation (1063 and 1128 cm(-1)) increased with respect to normal skin, whereas gauche conformation (1085 cm(-1)) disappeared. Our studies suggest that gels protected the skin against the stress of the natural defense mechanism caused by high levels of UV exposure.


Assuntos
Pele/efeitos da radiação , Raios Ultravioleta , Administração Tópica , Adulto , Aminoácidos/química , Aminoácidos/farmacologia , Análise por Conglomerados , Cicloexanóis/química , Cicloexanóis/farmacologia , Composição de Medicamentos , Feminino , Géis/química , Humanos , Microscopia Confocal , Poloxâmero/química , Análise de Componente Principal , Pele/efeitos dos fármacos , Pele/patologia , Análise Espectral Raman , Adulto Jovem
13.
Artigo em Inglês | MEDLINE | ID: mdl-26165619

RESUMO

In the confocal Raman spectra of skin dermis, the band area of proline and hydroxyproline in the fingerprint spectral region of 800-1000 cm(-1), where their vibrational modes are assigned, varied according to the age of the woman volunteers. The other aging effect observed in the Raman spectra is in the Amide I band in the spectral region between 1580 and 1720 cm(-1), where a softening in the Raman shift and intensity variation is detected depending of the vibrational groups. It is well known that the water quantity in healthy human skin dermis increases with age. However, in the elderly with diabetic disease, the increased sugar content directly affect the proline and hydroxyproline peaks as well as the water content in the dermis. The first approach in this work was theoretically modeling these systems using the RM1 semi empirical method, which represent proline and hydroxyproline interacting with one to four water molecule and with glucose. This task predicted how many hydrogen bonds were formed with the two amino acids and glucose. The subsequent model was built using DFT/B3LYP:3-21G procedures considering the amino acids chain formed by hydroxyproline and proline alone, which interact with one and four water molecules. We analyzed the dipole moment and polarizability variation to determine the hydrogen bonds in these systems. We chose the DFT/B3LYP:3-21G method to assign the vibrational modes of the skin dermis as a way to correlate the experimental trends. To explain the profile of lower intensity in the hydroxyproline and proline spectral region in diabetic elderly women, we proposed a chemical reaction of water interchange between the bonding amino acids and glucose, and we considered also the natural decreasing of collagen due to the glycation process. Theoretical results agree well with the observed experimental results.


Assuntos
Derme/química , Diabetes Mellitus/metabolismo , Modelos Moleculares , Teoria Quântica , Análise Espectral Raman , Água/química , Adulto , Idoso , Idoso de 80 Anos ou mais , Amidas/química , Humanos , Ligação de Hidrogênio , Hidroxiprolina/química , Pessoa de Meia-Idade , Prolina/química , Termodinâmica , Vibração , Adulto Jovem
14.
Environ Sci Technol ; 49(13): 7701-8, 2015 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-26018867

RESUMO

The effect of phospholipid on the biogeochemistry of pyrite oxidation, which leads to acid mine drainage (AMD) chemistry in the environment, was investigated. Metagenomic analyses were carried out to understand how the microbial community structure, which developed during the oxidation of pyrite-containing coal mining overburden/waste rock (OWR), was affected by the presence of adsorbed phospholipid. Using columns packed with OWR (with and without lipid adsorption), the release of sulfate (SO4(2-)) and soluble iron (FeTot) was investigated. Exposure of lipid-free OWR to flowing pH-neutral water resulted in an acidic effluent with a pH range of 2-4.5 over a 3-year period. The average concentration of FeTot and SO4(2-) in the effluent was ≥20 and ≥30 mg/L, respectively. In contrast, in packed-column experiments where OWR was first treated with phospholipid, the effluent pH remained at ∼6.5 and the average concentrations of FeTot and SO4(2-) were ≤2 and l.6 mg/L, respectively. 16S rDNA metagenomic pyrosequencing analysis of the microbial communities associated with OWR samples revealed the development of AMD-like communities dominated by acidophilic sulfide-oxidizing bacteria on untreated OWR samples, but not on refuse pretreated with phospholipid.


Assuntos
Ácidos/química , Ferro/química , Microbiota , Mineração , Fosfolipídeos/química , Sulfetos/química , Eliminação de Resíduos Líquidos , Bactérias/metabolismo , Biodegradação Ambiental , Sedimentos Geológicos/química , Concentração de Íons de Hidrogênio , Metagenômica , Oxirredução , Filogenia , Sulfatos/análise , Difração de Raios X
15.
Spectrochim Acta A Mol Biomol Spectrosc ; 146: 192-203, 2015 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-25813176

RESUMO

Theoretical and experimental bands have been assigned to the Fourier Transform Infrared (FT-IR) and FT-Raman spectra of the bis(diethyldithiocarbamate)Cd(II) complex, abbreviated as ([Cd(DDTC)2]). The calculations and spectral interpretation have been based on the DFT/B3LYP method, infrared and Raman second derivative spectra, and band deconvolution analysis to assist in the assignment of observed fundamentals. This study validated the unusual pseudo tetrahedral molecular structure formed around the Cd(II) cation. Surface-enhanced Raman scattering (SERS) was used to determine the interactions of the normal-modes of the diethyldithiocarbamate cadmium (II) complex on nano-structured silver surfaces. Natural bond orbital (NBO) analysis was also carried out to study the Cd(II) hybridization causing the pseudo tetrahedral geometry of the framework of the [Cd(DDTC)2] complex, and to confirm the charge transfer mechanisms through second order perturbation theory analysis of the Fox Matrix. In order to find out the electronic dispersion of the Mulliken atomic charges (MAC) in the normal modes, we calculated the MAC for each normal mode and correlated these values with the SERS effect. Experimental UV-Vis spectra were obtained and charge transfer bands were assigned. Good agreement between the calculated and experimental values for the vibrational and UV-Vis spectra was obtained.


Assuntos
Cádmio/química , Ditiocarb/química , Modelos Moleculares , Análise Espectral Raman
16.
J Water Health ; 13(1): 42-53, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25719464

RESUMO

We present proof-of-concept results for the elimination of waterborne bacteria by reactive minerals. We exposed Escherichia coli MG1655 suspended in water to the reactive mineral pyrite (FeS2) at room temperature and ambient light. This slurry eliminates 99.9% of bacteria in fewer than 4 hours. We also exposed Escherichia coli to pyrite leachate (supernatant liquid from slurry after 24 hours), which eliminates 99.99% of bacteria over the same time-scale. Unlike SOlar water DISinfection (SODIS), our results do not depend on the presence of ultraviolet (UV) light. We confirmed this by testing proposed SODIS additive and known photo-catalyst anatase (TiO2) for antibacterial properties and found that, in contrast to pyrite, it does not eliminate E. coli under our experimental conditions. Previous investigations of naturally antibiotic minerals have focused on the medical applications of antibiotic clays, and thus have not been conducted under experimental conditions resembling those found in water purification. In our examination of the relevant literature, we have not found previously reported evidence for the use of reactive minerals in water sanitization. The results from this proof-of-concept experiment may have important implications for future directions in household water purification research.


Assuntos
Antibacterianos/farmacologia , Desinfecção/métodos , Escherichia coli/efeitos dos fármacos , Ferro/farmacologia , Sulfetos/farmacologia , Microbiologia da Água , Purificação da Água/métodos , Carga Bacteriana , Catalase/química , Quelantes/química , Ácido Edético/química , Peróxido de Hidrogênio/química , Concentração de Íons de Hidrogênio , Titânio/farmacologia , Poluentes da Água
17.
Int J Hyg Environ Health ; 218(1): 19-27, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25107347

RESUMO

The inhalation of mineral particulates and other earth materials, such as coal, can initiate or enhance disease in humans. Workers in occupations with high particulate exposure, such as mining, are particularly at risk. The ability of a material to generate an inflammatory stress response (ISR), a measure of particle toxicity, is a useful tool in evaluating said exposure risk. ISR is defined as the upregulation of cellular reactive oxygen species (ROS) normalized to cell viability. This study compares the ISR of A549 human lung epithelial cells after exposure to well-characterized common metal-sulfide ore mineral separates. The evaluation of the deleterious nature of ore minerals is based on a range of particle loadings (serial dilutions of 0.002m(2)/mL stock) and exposure periods (beginning at 30min and measured systematically for up to 24h). There is a wide range in ISR values generated by the ore minerals. The ISR values produced by the sphalerite samples are within the range of inert materials. Arsenopyrite generated a small ISR that was largely driven by cell death. Galena showed a similar, but more pronounced response. Copper-bearing ore minerals generated the greatest ISR, both by upregulating cellular ROS and generating substantial and sustained cell death. Chalcopyrite and bornite, both containing ferrous iron, generated the greatest ISR overall. Particles containing Fenton metals as major constituents produce the highest ISR, while other heavy metals mainly generate cell death. This study highlights the importance of evaluating the chemistry, oxidation states and structure of a material when assessing risk management.


Assuntos
Pulmão/efeitos dos fármacos , Minerais/toxicidade , Exposição Ocupacional , Material Particulado/toxicidade , Estresse Fisiológico/efeitos dos fármacos , Sulfetos/toxicidade , Peróxido de Hidrogênio , Ferro , Pulmão/patologia , Espécies Reativas de Oxigênio , Fatores de Risco
18.
Rev. argent. radiol ; 78(4): 223-226, dic. 2014. ilus
Artigo em Espanhol | BINACIS | ID: bin-131239

RESUMO

Si bien la mayoría de los lipomas intestinales son asintomáticos y se diagnostican de manera casual, en algunas ocasiones pueden tener síntomas, como sangrado, diarrea o, con menor frecuencia, obstrucción o invaginación intestinal. Esta última en el adulto es una patología poco común y por lo general tiene una presentación subaguda crónica, cuyo diagnóstico es complicado. La principal técnica de imagen para el diagnóstico de la invaginación intestinal en adultos es la tomografía computada (TC). Solamente un 20% de las invaginaciones son colo-cólicas y en su mayoría son secundarias a un carcinoma. No obstante, en algunas pocas oportunidades pueden ser secundarias a una causa benigna, siendo el lipoma la más usual.(AU)


Even though most of the intestinal lipomas are asymptomatic and are diagnosed by chance, sometimes may have symptoms such as bleeding or diarrhea, and less frequently obstruction or intussusception. Intussusception in adults is a rare condition, and usually has a chronic-subacute presentation, and diagnosis is difficult. CT is the main radiological imaging test for diagnosis. Only 20% of the colonic invaginations are colo-colic, and in most cases are secondary to carcinoma. Rarely are secondary to a benign cause, being the intussusception secondary to a lipoma the most frecuent.(AU)

19.
Rev. argent. radiol ; 78(4): 223-226, dic. 2014. ilus
Artigo em Espanhol | LILACS | ID: lil-734612

RESUMO

Si bien la mayoría de los lipomas intestinales son asintomáticos y se diagnostican de manera casual, en algunas ocasiones pueden tener síntomas, como sangrado, diarrea o, con menor frecuencia, obstrucción o invaginación intestinal. Esta última en el adulto es una patología poco común y por lo general tiene una presentación subaguda crónica, cuyo diagnóstico es complicado. La principal técnica de imagen para el diagnóstico de la invaginación intestinal en adultos es la tomografía computada (TC). Solamente un 20% de las invaginaciones son colo-cólicas y en su mayoría son secundarias a un carcinoma. No obstante, en algunas pocas oportunidades pueden ser secundarias a una causa benigna, siendo el lipoma la más usual.


Even though most of the intestinal lipomas are asymptomatic and are diagnosed by chance, sometimes may have symptoms such as bleeding or diarrhea, and less frequently obstruction or intussusception. Intussusception in adults is a rare condition, and usually has a chronic-subacute presentation, and diagnosis is difficult. CT is the main radiological imaging test for diagnosis. Only 20% of the colonic invaginations are colo-colic, and in most cases are secondary to carcinoma. Rarely are secondary to a benign cause, being the intussusception secondary to a lipoma the most frecuent.


Assuntos
Humanos , Masculino , Intussuscepção , Lipoma , Vômito , Tomografia , Ultrassonografia , Gastrectomia , Náusea
20.
Lasers Med Sci ; 29(4): 1429-36, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24573956

RESUMO

The aim of this study was to find the apoptosis molecular markers involved in the cell death that might be related to photodynamic therapy (PDT) mechanisms in breast cancer. The mammary tumors were induced in 25 Sprague-Dawley female rats by a single, oral gavage of 7,12-dimethylbenz(a)anthracene (DMBA; 70 mg/kg body weight). Animals were divided into four groups: G1 (normal, without DMBA), G2 (control, without PDT treatment), G3 (euthanized 48 h after PDT), and G4 (euthanized 24 h after PDT). For PDT experiments, the photosensitizer used was Photodithazine, and 100 J/cm of light at a fluence rate of 100 mW/cm was delivered to treat lesions. A sample of each animal was investigated by quantitative real-time PCR using Rat Apoptosis RT2 Profiler™ PCR Array platform. The results showed 20 genes with differential expression between PDT and control groups. A significant upregulation was observed for pro-apoptotic genes CASP4, CASP12, CIDEA, GADD45A, and FAS and downregulation of anti-apoptotic genes MAPK8IP1, TNFRSF11B, and NAIP2 in PDT-treated tumors. These results indicate that these genes are more directly involved in cell apoptosis induced by PDT.


Assuntos
Antineoplásicos/uso terapêutico , Proteínas Reguladoras de Apoptose/genética , Glucosamina/análogos & derivados , Neoplasias Mamárias Experimentais/tratamento farmacológico , Fármacos Fotossensibilizantes/uso terapêutico , Animais , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/metabolismo , Feminino , Expressão Gênica , Glucosamina/farmacologia , Glucosamina/uso terapêutico , Lasers Semicondutores , Neoplasias Mamárias Experimentais/induzido quimicamente , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase em Tempo Real
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