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1.
Diabetol Metab Syndr ; 16(1): 175, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39054499

RESUMO

BACKGROUND: Dipeptidyl peptidase 4 (DPP-4) plays a crucial role in breaking down various substrates. It also has effects on the insulin signaling pathway, contributing to insulin resistance, and involvement in inflammatory processes like obesity and type 2 diabetes mellitus. Emerging effects of DPP-4 on bone metabolism include an inverse relationship between DPP-4 activity levels and bone mineral density, along with an increased risk of fractures. MAIN BODY: The influence of DPP-4 on bone metabolism occurs through two axes. The entero-endocrine-osseous axis involves gastrointestinal substrates for DPP-4, including glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptides 1 (GLP-1) and 2 (GLP-2). Studies suggest that supraphysiological doses of exogenous GLP-2 has a significant inhibitory effect on bone resorption, however the specific mechanism by which GLP-2 influences bone metabolism remains unknown. Of these, GIP stands out for its role in bone formation. Other gastrointestinal DPP-4 substrates are pancreatic peptide YY and neuropeptide Y-both bind to the same receptors and appear to increase bone resorption and decrease bone formation. Adipokines (e.g., leptin and adiponectin) are regulated by DPP-4 and may influence bone remodeling and energy metabolism in a paracrine manner. The pancreatic-endocrine-osseous axis involves a potential link between DPP-4, bone, and energy metabolism through the receptor activator of nuclear factor kappa B ligand (RANKL), which induces DPP-4 expression in osteoclasts, leading to decreased GLP-1 levels and increased blood glucose levels. Inhibitors of DPP-4 participate in the pancreatic-endocrine-osseous axis by increasing endogenous GLP-1. In addition to their glycemic effects, DPP-4 inhibitors have the potential to decrease bone resorption, increase bone formation, and reduce the incidence of osteoporosis and fractures. Still, many questions on the interactions between DPP-4 and bone remain unanswered, particularly regarding the effects of DPP-4 inhibition on the skeleton of older individuals. CONCLUSION: The elucidation of the intricate interactions and impact of DPP-4 on bone is paramount for a proper understanding of the body's mechanisms in regulating bone homeostasis and responses to internal stimuli. This understanding bears significant implications in the investigation of conditions like osteoporosis, in which disruptions to these signaling pathways occur. Further research is essential to uncover the full extent of DPP-4's effects on bone metabolism and energy regulation, paving the way for novel therapeutic interventions targeting these pathways, particularly in older individuals.

3.
J Consum Policy (Dordr) ; 45(1): 49-69, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35095141

RESUMO

Chilean consumer law and policy has a short but enthralling history. As compared with other jurisdictions such as EU countries, its bedrock is still in formation, particularly pertaining to its envisaged role in the regulatory spectrum applicable to consumer markets. However, this circumstance has not been a serious obstacle to several reforms carried out in recent years aimed at broadening its scope of action, including rethinking a proposal regarding the policy goals to be addressed by the national consumer agency, SERNAC. In that context, this article presents a brief account of the main features of Chilean consumer law, considering the current socioeconomic development level of the country, the main pieces of legislation concerning consumer protection in the Chilean legal framework-notably the Chilean Consumer Protection Act-as well as key elements of the public policy approach in this matter. A few examples of topics such as product liability and sale and purchase of consumer goods are also analysed in order to allow a comparison of the Chilean experience in consumer protection with other jurisdictions.

4.
J Virus Erad ; 7(3): 100053, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34621530

RESUMO

HIV-1 is able to persist in the face of potent antiretroviral therapy (ART). A number of strategies are being explored to allow ART-free viral remission or viral eradication. In order to gauge the progress of these strategies, assays with which to measure viral reservoir size and activity are needed. In a large percentage of aviremic individuals on suppressive ART, viral transcripts can be detected in peripheral blood CD4+ T cells. While this cell-associated RNA has been considered as a marker of viral reservoir activity, it is unclear whether cell-associated viral transcripts in aviremic individuals originate from biologically competent proviruses as opposed to being a product of abortive transcription from defective proviruses. We assessed whether cell-associated viral RNA in peripheral blood CD4+ T cells from aviremic individuals on ART originated from biologically competent proviruses. We demonstrate that cell-associated viral RNA transcripts were highly related to viral sequences obtained by ex vivo outgrowth. This relationship was also observed when viral transcription in the outgrowth cultures was limited to donor CD4+ T cells. Our study indicates that cell-associated viral RNA warrants further consideration as a viral reservoir surrogate in individuals on suppressive ART.

5.
Toxicol Appl Pharmacol ; 429: 115684, 2021 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-34437931

RESUMO

Metals and metalloids including lead (Pb), arsenic (As) and manganese (Mn) can occur as mixtures in occupational contexts, such as mines. These chemicals are all known to be neurotoxic and provoke changes in heme metabolism also known to induce neurotoxicity. The objective of this work was to propose a multi-biomarker (BM) methodology to screen subjects exposed to the mixture of Pb, As and Mn and assess the severity of their exposure/effects, in an individual basis. The urinary levels of the metals, dela-aminolevulinic acid (ALA) and porphyrins were determined in Portuguese miners and in a control group. The combination of Pb and As urinary levels had the highest capability to identify subjects occupationally exposed to this mixture in mines, as evaluated through Receiver Operating Characteristic (ROC) (A = 98.2%; p < 0.05), allowing that 94.2% of 86 studied subjects were properly identified and the generation of an equation indicating the odd of a subject be considered as exposed to the metal mixture. The combination of urinary ALA and porphyrins revealed to be best one to be applied in the assessment of subjects with high, intermediate, and low magnitudes of exposure/effects, with 95.7% of 46 miners classified correctly according to their severity sub-group and allowing to generate equations, which can be applied in new subjects. The proposed methodology showed a satisfactory performance, evaluating in an integrated manner the magnitude of exposure/effects of the exposed workers, may contributing to improve the control of their health.


Assuntos
Arsênio/efeitos adversos , Monitoramento Biológico , Biomarcadores Ambientais , Poluentes Ambientais/efeitos adversos , Chumbo/efeitos adversos , Manganês/efeitos adversos , Exposição Ocupacional/efeitos adversos , Ácido Aminolevulínico/urina , Arsênio/urina , Poluentes Ambientais/urina , Humanos , Chumbo/urina , Manganês/urina , Mineração , Saúde Ocupacional , Porfirinas/urina , Valor Preditivo dos Testes , Medição de Risco , Urinálise
6.
Actas Urol Esp (Engl Ed) ; 44(9): 604-610, 2020 Nov.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-32843150

RESUMO

OBJECTIVE: To compare the activity the Urology Department of a Portuguese Academic Hospital during the state of emergency and the equivalent period at the previous year. We compared the number of elective consultations and diagnostic urologic examinations, number and type of elective surgeries, as well as patients' demographic characteristics and main causes of presentation to Urology Emergency Department (ED) during the two mentioned periods MATERIALS AND METHODS: Data from 691 patients coming to emergency department were collected from institutional clinical software from March 18 th 2020 to May 2 nd 2020 - and from the same period the previous year. Data collected were age, sex, day of the presentation to Emergency Department, referral from other hospitals, triage color, reason of admission, diagnosis of discharge, and the need for emergency surgery or hospitalization. In order to identify associations between demographic and clinical variables with having been submitted to an emergency surgery (outcome), logistic regression models were applied. RESULTS: Multivariable analysis showed an association of sex with being submitted to surgery, 65.6% decrease in the odds for the male gender. The period (COVID versus non-COVID) did not show a significant association with surgery. CONCLUSION: Our department experienced a noticeable activity reduction. We also observe a reduction in urgent causes to attend the ED considered less serious. The percentage of cases requiring emergency surgery and hospitalization was higher during COVID-period.


Assuntos
Betacoronavirus , Infecções por Coronavirus/epidemiologia , Serviço Hospitalar de Emergência/estatística & dados numéricos , Pneumonia Viral/epidemiologia , Urologia/estatística & dados numéricos , Fatores Etários , Idoso , COVID-19 , Técnicas de Diagnóstico Urológico/estatística & dados numéricos , Técnicas de Diagnóstico Urológico/tendências , Procedimentos Cirúrgicos Eletivos/estatística & dados numéricos , Procedimentos Cirúrgicos Eletivos/tendências , Serviço Hospitalar de Emergência/tendências , Feminino , Hospitalização/estatística & dados numéricos , Hospitalização/tendências , Hospitais Universitários , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Pandemias , Portugal/epidemiologia , Consulta Remota/estatística & dados numéricos , SARS-CoV-2 , Fatores Sexuais , Centros de Atenção Terciária , Triagem/métodos , Doenças Urológicas/epidemiologia , Urologia/tendências
7.
J Virol ; 94(15)2020 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-32461309

RESUMO

Oregano essential oil has long been known for its health-promoting benefits. Here, we report its activity against viral replication. Oregano oil was found to specifically inhibit lentiviruses, such as human and simian immunodeficiency viruses (HIV and SIV), irrespective of virus tropism, but not hepatitis C virus, adenovirus 5 (ADV5), Zika virus, and influenza (H1N1) virus. Oregano oil's most abundant components, carvacrol and its isomer, thymol, were shown to block virus-target cell fusion while not perturbing other stages of the virus life cycle. We detected changes in virus particle density, suggesting that cholesterol depletion from the HIV-1 envelope membrane reduces virus entry. Furthermore, infection was rescued by adding exogenous cholesterol. The evolution of viral resistance to carvacrol supported this mechanism of action with the identification of mutations in the viral gp41 fusion protein that counteracted cholesterol depletion. In addition, resistance to carvacrol emerged later than typically observed for other clinically used drugs, strengthening its antiviral potential. Structure-activity relationship studies revealed key motifs of carvacrol and thymol required for HIV neutralization and identified previously unknown active analogs. Carvacrol was also shown to additively cooperate with antiretroviral therapy. In sum, oregano oil and improved carvacrol and thymol analogs could be considered to supplement current HIV therapeutics.IMPORTANCE Oregano essential oil has multiple benefits in traditional medicine, cosmetics, and food industries. Carvacrol and its analog, thymol, are well-described components of oregano oil. Here, we show that these compounds inhibit HIV-target cell fusion independently of viral tropism. Our results suggest that carvacrol and thymol alter the cholesterol content of the viral membrane, blocking HIV-1 entry into the target cell. Resistance to carvacrol has selected for viruses with mutations in the viral envelope glycoprotein, gp41. This protein is known for its interaction with cholesterol present in membrane lipid rafts. Together, these results demonstrate the potential of therapies targeting the viral envelope membrane, and oregano oil is a safe supplement to antiretrovirals, potentially delaying disease progression and resistance development.


Assuntos
Cimenos/farmacologia , Proteína gp41 do Envelope de HIV/metabolismo , HIV-1/metabolismo , Origanum/química , Óleos de Plantas/farmacologia , Internalização do Vírus/efeitos dos fármacos , Animais , Colesterol/genética , Colesterol/metabolismo , Cimenos/química , Farmacorresistência Viral , Proteína gp41 do Envelope de HIV/genética , Infecções por HIV/tratamento farmacológico , Infecções por HIV/genética , Infecções por HIV/metabolismo , HIV-1/genética , Células HeLa , Humanos , Macaca mulatta , Mutação , Óleos de Plantas/química
8.
Sci Rep ; 9(1): 18308, 2019 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-31797952

RESUMO

The coupling between electric, magnetic and elastic features in multiferroic materials is an emerging field in materials science, with important applications on alternative solid-state cooling technologies, energy harvesting and sensors/actuators. In this direction, we developed a thorough investigation of a multiferroic composite, comprising magnetocaloric/magnetostrictive Gd[Formula: see text]Si[Formula: see text]Ge[Formula: see text] microparticles blended into a piezo- and pyroelectric poly(vinylidene) fluoride (PVDF) matrix. Using a simple solvent casting technique, the formation and stabilization of PVDF electroactive phases are improved when the filler content increases from 2 to 12 weight fraction (wt.%). This effect greatly contributes to the magnetoelectric (ME) coupling, with the ME coefficient [Formula: see text] increasing from 0.3 V/cm.Oe to 2.2 V/cm.Oe, by increasing the amount of magnetic material. In addition, magnetic measurements revealed that the ME-coupling has influenced the magnetocaloric effect via a contribution from the electroactive polymer and hence leading to a multicaloric effect. These results contribute to the development of multifunctional systems for novel technologies.

9.
Rev. chil. nutr ; 46(6): 735-745, dic. 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1058136

RESUMO

The aim of this study was to evaluate the nutritional and behavioral effects of a cafeteria diet in dams during the breastfeeding period and in their offspring from weaning until early adulthood (70 days old). Pregnant Wistar rats were fed a chow diet until delivery. Postnatally (D0), litters were culled to 8 pups and lactating dams received control (CTRL n= 6) or cafeteria (CAF n= 6) diets and water ad libitum. At the end of the breastfeeding period, male offspring were placed in individual boxes receiving the same treatment from their respective dams (CTRL or CAF) until adulthood (70 days). All nutritional and behavioral evaluations were performed with the dams (n= 12) during the breastfeeding phase and with the male offspring (n= 24) after weaning to adulthood. CAF dams demonstrated a lower caloric and protein intake; higher intake of fats; loss of weight; greater accumulation of adipose tissue; and an anxiolytic effect. CAF male offspring showed lower caloric intake; higher intake of fats; and accumulation of adipose tissue. In addition, these animals continued to have decreased body weight, body length and tibia-femur length in relation to CTRL. In dams, a cafeteria diet promoted alterations in body composition and anxiety, and in offspring the diet resulted in adequate development.


El objetivo de este estudio fue evaluar los efectos nutricionales y de comportamiento de la dieta de la cafetería en las madres durante el período de lactancia materna y en su descendencia desde el destete hasta la edad adulta temprana (70 días de edad). Ratas Wistar embarazadas fueron alimentadas con una dieta estándar hasta el parto. Postnatalmente (D0), las camadas se ajustaron en 8 crías y las madres lactantes recibieron las dietas control (CTRL n= 6) o cafetería (CAF n= 6) además de agua ad libitum. Al final del período de lactancia materna, las proles machos fueron colocados en cajas individuales recibiendo el mismo tratamiento de sus respectivas madres (CTRL o CAF) hasta la edad adulta (70 días). Todas las evaluaciones nutricionales y comportamentales se realizaron con las madres (n= 12) durante la fase de lactancia y con la prole masculina (n= 24) después del destete hasta la edad adulta. Las madres CAF demostraron una menor ingesta calórica y proteica; mayor ingestión de grasas; pérdida de peso; mayor acumulación de tejido adiposo; y un efecto ansiolítico. La prole masculina CAF presentó menor consumo calórico; mayor ingestión de grasas; y la acumulación de tejido adiposo. Además, estos animales presentaron menor peso corporal, longitud corporal, y longitud de la tibia-fémur, en relación a CTRL. En las madres, la dieta de cafetería promovió cambios en la composición corporal y ansiedad, y en la prole la dieta comprometió el desarrollo adecuado.


Assuntos
Animais , Masculino , Feminino , Gravidez , Ratos , Dieta/efeitos adversos , Comportamento Alimentar , Ansiedade/etiologia , Efeitos Tardios da Exposição Pré-Natal/etiologia , Desmame , Comportamento Animal , Aleitamento Materno , Avaliação Nutricional , Tecido Adiposo , Análise de Variância , Ratos Wistar
10.
Arq. bras. med. vet. zootec. (Online) ; 71(3): 723-731, May-June 2019. tab, ilus
Artigo em Inglês | VETINDEX, LILACS | ID: biblio-1011327

RESUMO

The aim of this study was to evaluate the supplementation of embryo culture medium with antioxidant obtained from oily extract of Lippia origanoides on in vitro blastocyst development and quality. Oocytes collected from slaughterhouse ovaries were matured and fertilized in vitro following standard laboratory procedures. Zygotes were cultured in SOF medium supplemented according to the following treatments: T1 embryo culture medium without antioxidant supplementation; T2)50µM/mL Cysteamine; T3)2.5µg/mL; T4)5.0µg/mL and T5)10.0µg/mL of antioxidant obtained from oily extract of Lippia origanoides. On the seventh day of culture, the blastocysts were fixed and evaluated for apoptosis rates, number of total cell and inner cell mass cells by means of the TUNEL Test. The use of antioxidants during cultivation did not increase (P> 0.05) the final blastocyst production rate. The treatments T2, T3, T4 and T5 had the lowest (P< 0.05) apoptotic indexes (4.5±1.1%, 8.4±2.5%, 3.4±1.1% and 5.5±0.9%, respectively) when compared to T1 treatment (10.0±1.4%). The number of inner cell mass did not differ (P> 0.05) among embryos from different treatments. The addition of antioxidant obtained from oily extract of Lippia origanoides reduces the apoptosis rate and improves the quality without increasing the total in vitro production of bovine embryos.(AU)


O objetivo desse estudo foi avaliar a suplementação de meio de cultura de embriões com antioxidante obtido do extrato oleoso da Lippia origanoides no desenvolvimento e na qualidade de blastocistos produzidos in vitro. Oócitos coletados de ovários de matadouros foram maturados e fertilizados in vitro segundo procedimento laboratorial padrão. Zigotos foram cultivados em meio SOF suplementado de acordo com os seguintes tratamentos: T1) meio de cultivo embrionário sem suplementação antioxidantes; T2) 50µM/mL Cisteamina; T3) 2,5µg/mL; T4) 5,0µg/mL e T5) 10,0µg/mL do antioxidante obtido do extrato oleoso de Lippia origanoides. No sétimo dia de cultivo, os blastocistos foram fixados e avaliados para taxa de apoptose, número total de células e massa celular interna através do teste TUNEL. O uso de antioxidantes durante cultivo não aumentou (P>0,05) a taxa de produção final de blastócitos. Os tratamentos T2, T3, T4 e T5 tiverem menor índice apoptótico (p>0,05 - 4,5±1,1%, 8,4±2,5%, 3,4±1,1% e 5,5±0,9%, respectivamente) quando comparados a T2 (10,0±1,4%). O valor de massa celular interna não diferenciou (p>0,05) entre embriões de diferentes tratamentos. A adição de antioxidante obtido do extrato oleoso de Lippia origanoides reduziu a taxa de apoptose e melhorou a qualidade sem aumentar a produção in vitro de embriões bovinos.(AU)


Assuntos
Animais , Bovinos , Apoptose , Lippia , Técnicas de Cultura Embrionária/veterinária , Desenvolvimento Embrionário , Antioxidantes
11.
Theriogenology ; 123: 132-138, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30300810

RESUMO

Embryo mobility occurs as a result of prostaglandin production by the embryo and endometrium, promoting uterine smooth muscle contractions, which propels the embryonic vesicle through the lumen. Non-steroidal anti-inflammatory drugs (NSAIDs), as flunixin meglumine, are routinely used in equine medicine and can alter the conceptus mobility if applied in early pregnancy, which may impair maternal recognition of pregnancy. The objective of this study was to evaluate and compare the effect of flunixin meglumine (FM; 1.1 mg/kg IV), firocoxib (FIRO; 0.2 mg/kg PO), and meloxicam (ML; 0.6 mg/kg, IV), on the embryo mobility. Thirty mares were divided into three groups (n = 10 per treatment). After the pregnancy diagnosis on day 12 after ovulation, the embryo mobility was evaluated by transrectal ultrasonography every 5 min for 1 h in order to visualize the location of the embryo. In all mares, three evaluations were performed: immediately before treatment (pre-treatment), after NSAID administration and 24 h after treatment. In group FM, embryo mobility decreased, from 5.8 ±â€¯0.3 movements/hour (m/h) to 2.3 ±â€¯0.5 m/h (p < 0.05) and, after 24 h the values were similar to the pre-treatment evaluation (5.9 ±â€¯0.2 m/h). Likewise, ML treatment caused a decrease of embryo movements, from 5.9 ±â€¯0.3 to 1.9 ±â€¯0.3 m/h (p < 0.05), 24 h after treatment values were 5.7 ±â€¯0.4 m/h. Treatment with FIRO did not interfere with embryo mobility (5.7 ±â€¯0.4; 5.8 ±â€¯0.3 and 5.6 ±â€¯0.3 embryo movements in the first, second and third evaluation, respectively). In conclusion, FIRO was the only NSAID that did not alter the embryo mobility and may be the safest NSAID for use in early pregnant mares.


Assuntos
4-Butirolactona/análogos & derivados , Clonixina/análogos & derivados , Embrião de Mamíferos/fisiologia , Cavalos/fisiologia , Meloxicam/farmacologia , Sulfonas/farmacologia , 4-Butirolactona/farmacologia , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Clonixina/farmacologia , Embrião de Mamíferos/efeitos dos fármacos , Feminino , Cavalos/embriologia , Gravidez , Prostaglandinas/metabolismo , Ultrassonografia Pré-Natal/veterinária
13.
Lett Appl Microbiol ; 67(3): 285-291, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29908032

RESUMO

Vulvovaginal candidiasis (VVC) is an inflammatory disease of the vulva and vagina caused by different yeasts of the genus Candida which is responsible for infection in pregnant patients who attended Maternidade Escola Januário Cicco, Rio Grande do Norte, Brazil. From 41 samples, 19 yeasts were identified phenotypically as Candida albicans and one as Candida glabrata which is reported as the non-albicans species most frequently isolated from vulvovaginitis. The susceptibility to selected antifungal agents (flucytosine, fluconazole, voriconazole, amphotericin B, caspofungin and micafungin) was determined, and the association between patient-related signs and symptoms aided the construction of an epidemiological profile. Antifungal susceptibility testing performed by automated method showed that all strains were sensitive to the drugs tested, including the C. glabrata specimen despite its known resistance or dose-dependent susceptibility to azole derivatives. Regarding patient signs and symptoms, no statistically significant association between these and the establishment of VVC was found. It can be concluded that the laboratorial diagnosis of VVC is necessary prior to the administration of treatment, since only 48·78% of the patients had VVC but for all of them antifungal therapy were prescribed. SIGNIFICANCE AND IMPACT OF THE STUDY: Vulvovaginal candidiasis (VVC) is a problem that affects a significant number of pregnant women worldwide. This type of fungal infection generates great discomfort due to the symptomatology and difficulties of diagnosis and treatment. In view of the scarcity of data in the State of Rio Grande do Norte, Brazil, regarding studies carried out on fungal populations of the genus Candida associated with VVC in pregnant women, this study considered relevant, the phenotypic and genotypic identification of the species, to estimate the prevalence, to determine their susceptibility to the antifungal and to correlate with signs and symptoms.


Assuntos
Antifúngicos/farmacologia , Candida/efeitos dos fármacos , Candidíase Vulvovaginal/microbiologia , Complicações na Gravidez/microbiologia , Adolescente , Adulto , Anfotericina B/farmacologia , Brasil/epidemiologia , Candida/genética , Candida/isolamento & purificação , Candida glabrata/isolamento & purificação , Candidíase Vulvovaginal/epidemiologia , Equinocandinas/farmacologia , Feminino , Fluconazol/farmacologia , Humanos , Lipopeptídeos/farmacologia , Micafungina , Testes de Sensibilidade Microbiana , Gravidez , Complicações na Gravidez/epidemiologia , Prevalência , Instituições Acadêmicas/estatística & dados numéricos , Adulto Jovem
14.
J Integr OMICS ; 8(1)2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30666282

RESUMO

Chronic occupational exposures to low levels of metal mixtures necessitates biomonitoring of exposed workers. However, a single biomarker (BM) is rarely sufficient to ascertain the exposure of an individual to a complex mixture, with multiparameter analysis of the same sample considered recently as a preferred approach. Porphyrins are formed as intermediates of heme biosynthesis and different metals can exert their effects at different points of this metabolic pathway, leading to changed urinary porphyrins excretion profiles. The aim of this work was to develop a model that could serve to identify, on an individual basis, multiple metal exposure resulting from mining work, by using urinary porphyrin profiles. Urine samples of workers were obtained from a Portuguese mining company and a non-occupationally exposed group was used as control. The levels of uro-, hepta-, hexa-, penta-, copro- and protoporphyrins were determined by HPLC. It was observed that only heptaporphyrin levels in miners were significantly (p<0.05) different from controls. However, when the concentrations of all porphyrins were combined by binary logistic regression, their ability to discriminate between miners and controls was higher than each one of the porphyrins alone, as indicated by a greater curve' area under a ROC curve. Moreover, when the combined porphyrins were used to calculate the probability of each subject fit in the occupationally exposed group, 83% of 47 individuals were correctly identified with respect to their type of exposure. These results suggest that the integration of the urinary porphyrin profile is a promising tool for the detection of subjects exhibiting biochemical modifications due to occupational exposure to metals in mines.

15.
Arq. bras. med. vet. zootec. (Online) ; 69(6): 1385-1392, nov.-dez. 2017. ilus, tab
Artigo em Português | LILACS, VETINDEX | ID: biblio-909701

RESUMO

Avaliou-se o efeito da adição do ácido linoleico conjugado (CLA) ao meio de cultivo in vitro na viabilidade pós-vitrificação de embriões F1 Holandês x Zebu. Foram utilizados três meios de cultivo: controle (n=340 oócitos): meio SOF e soro fetal bovino (SFB), sem o CLA; SFB+CLA (n=359 oócitos): meio SOF, SFB e CLA; CLA (n=339 oócitos): meio SOF e CLA, sem o SFB. Todos os blastocistos produzidos foram submetidos à vitrificação, pelo método de Open Pulled Straw. Quinze blastocistos de cada tratamento foram fixados para quantificação lipídica por coloração com Sudan Black B. Para avaliar a viabilidade embrionária, foi observada a capacidade de reexpansão e eclosão pós-aquecimento dos embriões (controle=27; SFB+CLA=30; CLA=17). Foram realizadas transferências em um ou dois embriões por receptora para avaliação da sobrevivência in vivo: T1 [receptoras que receberam um blastocisto (n=17 embriões, sendo controle=5, SFB+CLA=6 e CLA=6)]; T2 [receptoras que receberam dois blastocistos, (n= 54 embriões, sendo controle=18, SFB+CLA=14 e CLA=22)]. Não houve diferença nas taxas de clivagem (62,1%; 74,0%; 74,0% para controle; SFB+CLA; CLA, respectivamente), produção de blastocistos em relação aos clivados (59,7%; 47,7%; 38,3% para controle; SFB+CLA; CLA, respectivamente) e produção de blastocistos em relação ao total de oócitos (37,1%; 35,4%; 28,3% para controle; SFB+CLA; CLA, respectivamente) (P>0,05). Houve diminuição de gotículas lipídicas nos embriões cultivados em meio suplementado com CLA em relação aos embriões cultivados na presença do SFB e na ausência do CLA (P<0,05). A taxa de reexpansão foi maior no grupo controle (70,4%) em relação ao CLA (47,1%) e menor no grupo SFB+CLA (43,3%) (P<0,05). O CLA foi eficaz em reduzir a deposição de lipídeos intracitoplasmáticos nas células embrionárias, porém não houve diferença de viabilidade após a desvitrificação dos embriões.(AU)


The effect of adding conjugated linoleic acid (CLA) to the culture media on the viability after cryopreservation of F1 Holstein X Zebu embryos was evaluated. Three different culture media were tested: control (n = 340 oocytes): SOF medium and fetal bovine serum (FBS) without the CLA; FBS + CLA (n = 359 oocytes): SOF, FBS and CLA; CLA (n = 339 oocytes): SOF and CLA without the FBS. The produced blastocysts were subjected to vitrification, by the Open Pulled Straw method. Fifteen blastocysts per treatment were fixed for lipid quantification by staining with Sudan Black B. Embryo re-expansion and hatching capability were used to assess viability (control = 27; FBS + CLA = 30; CLA = 17). Transfers of one or two embryos to recipients were performed to evaluate in vivo survival: T1 [recipients that received one blastocyst (n=17 embryos, Control=5, FBS+CLA=6 and CLA=6)]; T2 [recipients that received two blastocysts (n =54 embryos, Control=18, FBS+CLA=14 and CLA=22)]. There was no difference in cleavage rate (62.1%; 74%; 74% for Control; FBS + CLA, CLA, respectively), blastocyst production in relation to the cleaved structures (59.7%; 47.7%; 38 3% for Control; FBS + CLA, CLA, respectively) and blastocyst production relative to the total oocytes (37.1%, 35.4%, 28.3% for Control; FBS + CLA, CLA, respectively) between treatments (P> 0.05). A reduction of lipid droplets was observed in embryos cultured in medium supplemented with CLA compared to embryos cultured in the FCS in the absence and presence of CLA (P <0.05). The reexpansion rate was higher in the Control group (70.4%) compared to the CLA (47.1%) and lowest for FBS+CLA (43.3%) (P<0.05). The hatching rates were similar among treatments, 42.1%; 23.1%; 25% for control; SFB + CLA; CLA respectively (P>0.05). Only one pregnancy was observed in early and confirmatory diagnosis, as the result of a Control group embryo transfer. Although embryos cultured with CLA have shown smaller intracytoplasmic lipid content, no difference was observed in viability following vitrification between treatments.(AU)


Assuntos
Animais , Bovinos , Criopreservação/veterinária , Ácidos Linoleicos Conjugados/uso terapêutico , Embrião de Mamíferos , Vitrificação , Técnicas In Vitro/veterinária
16.
Soft Matter ; 13(44): 8331-8336, 2017 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-29058731

RESUMO

Dynamic wetting behaviors on soft solids are important to interpret complex biological processes from cell-substrate interactions. Despite intensive research studies over the past half-century, the underlying mechanisms of spreading behaviors are not clearly understood. The most interesting feature of wetting on soft matter is the formation of a "wetting ridge", a surface deformation by a competition between elasticity and capillarity. Dynamics of the wetting ridge formed at the three-phase contact line underlies the dynamic wetting behaviors, but remains largely unexplored mostly due to limitations in indirect observation. Here, we directly visualize wetting ridge dynamics during continuous- and stick-slip motions on a viscoelastic surface using X-ray microscopy. Strikingly, we discover that the ridge spreads spontaneously during stick and triggers contact line depinning (stick-to-slip transition) by changing the ridge geometry which weakens the contact line pinning. Finally, we clarify 'viscoelastic-braking', 'stick-slipping', and 'stick-breaking' spreading behaviors through the ridge dynamics. In stick-breaking, no ridge-spreading occurs and contact line pinning (hysteresis) is enhanced by cusp-bending while preserving a microscopic equilibrium at the ridge tip. We have furthered the understanding of spreading behaviors on soft solids and demonstrated the value of X-ray microscopy in elucidating various dynamic wetting behaviors on soft solids as well as puzzling biological issues.

17.
Arq. bras. med. vet. zootec. (Online) ; 69(5): 1326-1330, set.-out. 2017. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-879231

RESUMO

Doenças infecciosas são as maiores responsáveis por falhas reprodutivas (FR) em cadelas, causando aborto, morte fetal e natimortalidade. Este estudo teve como objetivo investigar a associação entre agentes infecciosos, FR inexplicáveis e anemia em cadelas. Todas as amostras maternas e fetais foram negativas para a presença dos principais agentes infecciosos causadores de FR: herpes vírus canino 1, Neospora caninum, Brucella spp. e B. canis, enquanto agentes como o de Leishmania spp., parvovírus canino, Ehrlichia canis e Anaplasma platys foram encontrados em sangue materno. Coinfecções de A. platys/E. canis e A. platys/Leishmania spp. foram diagnosticadas. Os resultados indicam que os animais com anemia causadas por doenças transmitidas por vetores podem ser mais suscetíveis a sofrerem FR do que animais com valores hematológicos normais.(AU)


Assuntos
Animais , Feminino , Gravidez , Cães , Aborto Animal/etiologia , Infecções por Anaplasmataceae/complicações , Anemia/veterinária , Morte Fetal , Ehrlichia , Leishmaniose/complicações
18.
Adv Neurobiol ; 18: 227-265, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28889271

RESUMO

Metals are the oldest toxins known to humans. Metals differ from other toxic substances in that they are neither created nor destroyed by humans (Casarett and Doull's, Toxicology: the basic science of poisons, 8th edn. McGraw-Hill, London, 2013). Metals are of great importance in our daily life and their frequent use makes their omnipresence and a constant source of human exposure. Metals such as arsenic [As], lead [Pb], mercury [Hg], aluminum [Al] and cadmium [Cd] do not have any specific role in an organism and can be toxic even at low levels. The Substance Priority List of Agency for Toxic Substances and Disease Registry (ATSDR) ranked substances based on a combination of their frequency, toxicity, and potential for human exposure. In this list, As, Pb, Hg, and Cd occupy the first, second, third, and seventh positions, respectively (ATSDR, Priority list of hazardous substances. U.S. Department of Health and Human Services, Public Health Service, Atlanta, 2016). Besides existing individually, these metals are also (or mainly) found as mixtures in various parts of the ecosystem (Cobbina SJ, Chen Y, Zhou Z, Wub X, Feng W, Wang W, Mao G, Xu H, Zhang Z, Wua X, Yang L, Chemosphere 132:79-86, 2015). Interactions among components of a mixture may change toxicokinetics and toxicodynamics (Spurgeon DJ, Jones OAH, Dorne J-L, Svendsen C, Swain S, Stürzenbaum SR, Sci Total Environ 408:3725-3734, 2010) and may result in greater (synergistic) toxicity (Lister LJ, Svendsen C, Wright J, Hooper HL, Spurgeon DJ, Environ Int 37:663-670, 2011). This is particularly worrisome when the components of the mixture individually attack the same organs. On the other hand, metals such as manganese [Mn], iron [Fe], copper [Cu], and zinc [Zn] are essential metals, and their presence in the body below or above homeostatic levels can also lead to disease states (Annangi B, Bonassi S, Marcos R, Hernández A, Mutat Res 770(Pt A):140-161, 2016). Pb, As, Cd, and Hg can induce Fe, Cu, and Zn dyshomeostasis, potentially triggering neurodegenerative disorders, such as Alzheimer's disease (AD) and Parkinson's disease (PD). Additionally, changes in heme synthesis have been associated with neurodegeneration, supported by evidence that a decline in heme levels might explain the age-associated loss of Fe homeostasis (Atamna H, Killile DK, Killile NB, Ames BN, Proc Natl Acad Sci U S A 99(23):14807-14812, 2002).The sources, disposition, transport to the brain, mechanisms of toxicity, and effects in the central nervous system (CNS) and in the hematopoietic system of each one of these metals will be described. More detailed information on Pb, Mn, Al, Hg, Cu, and Zn is available in other chapters. A major focus of the chapter will be on Pb toxicity and its interaction with other metals.


Assuntos
Intoxicação do Sistema Nervoso por Metais Pesados/metabolismo , Alumínio/intoxicação , Animais , Intoxicação por Arsênico/metabolismo , Intoxicação por Arsênico/fisiopatologia , Intoxicação por Cádmio/metabolismo , Intoxicação por Cádmio/fisiopatologia , Misturas Complexas , Cobre/intoxicação , Exposição Ambiental , Intoxicação do Sistema Nervoso por Metais Pesados/fisiopatologia , Humanos , Ferro/intoxicação , Intoxicação do Sistema Nervoso por Chumbo/metabolismo , Intoxicação do Sistema Nervoso por Chumbo/fisiopatologia , Intoxicação por Manganês/metabolismo , Intoxicação por Manganês/fisiopatologia , Intoxicação do Sistema Nervoso por Mercúrio/metabolismo , Intoxicação do Sistema Nervoso por Mercúrio/fisiopatologia , Síndromes Neurotóxicas/metabolismo , Síndromes Neurotóxicas/fisiopatologia , Zinco/intoxicação
19.
Adv Mater ; 29(41)2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28906570

RESUMO

Dispersions of nanoscale precipitates in metallic alloys have been known to play a key role in strengthening, by increasing their strain hardenability and providing resistance to deformation. Although these phenomena have been extensively investigated in the last century, the traditional approaches employed in the past have not rendered an authoritative microstructural understanding in such materials. The effect of the precipitates' inherent complex morphology and their 3D spatial distribution on evolution and deformation behavior have often been precluded. This study reports, for the first time, implementation of synchrotron-based hard X-ray nanotomography in Al-Cu alloys to measure kinetics of different nanoscale phases in 3D, and reveals insights behind some of the observed novel phase transformation reactions. The experimental results of the present study reconcile with coarsening models from the Lifshitz-Slyozov-Wagner theory to an unprecedented extent, thereby establishing a new paradigm for thermodynamic analysis of precipitate assemblies. Finally, this study sheds light on the possibilities for establishing new theories for dislocation-particle interactions, based on the limitations of using the Orowan equation in estimating precipitation strengthening.

20.
Biophys Chem ; 228: 69-80, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28711675

RESUMO

T-2410 and T-2429 are HIV fusion inhibitor peptides (FI) designed to present a higher efficiency even against HIV strains that developed resistance against other FIs. Similar peptides were shown to interact with model membranes both in the liquid disordered phase and in the liquid ordered state. Those results indicated that such interaction is important to function and could be correlated with their effectiveness. Extensive molecular dynamics simulations were carried out to investigate the interactions between both T-2410 and T-2429 with bilayers of pure 1-palmitoyl-2-oleoyl-phosphatidylcholine (POPC) and a mixture of POPC/cholesterol (Chol) (1:1). It was observed that both peptides interact strongly with both membrane systems, especially with the POPC/Chol systems, where these peptides show the highest number of H-bonds observed so far. T-2410 and T-2429 showed higher extent of interaction with bilayers when compared to T-20 or T-1249 in previous studies. This is most notable in POPC/Chol membranes where, although able to form H-bonds with Chol, they do so to a lesser extent than T-1249 does, the latter being the only FI peptide so far that was observed to form H-bonds with Chol. This behavior suggests that interaction of FI peptides with rigid Chol rich membranes may not be as dependent from peptide/Chol H-bond formation as previous results of T-1249 behavior led to believe. As in other similar peptides, the higher ability to interact with membranes shown by T-2410 and T2429 is probably correlated with its higher inhibitory efficiency.


Assuntos
Inibidores da Fusão de HIV/química , Bicamadas Lipídicas/química , Simulação de Dinâmica Molecular , Sequência de Aminoácidos , Colesterol/química , HIV/efeitos dos fármacos , Inibidores da Fusão de HIV/metabolismo , Inibidores da Fusão de HIV/farmacologia , Humanos , Ligação de Hidrogênio , Bicamadas Lipídicas/metabolismo , Dados de Sequência Molecular , Peptídeos/química , Peptídeos/metabolismo , Peptídeos/farmacologia , Fosfatidilcolinas/química , Estrutura Secundária de Proteína , Alinhamento de Sequência , Termodinâmica
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