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1.
Toxicol Appl Pharmacol ; : 116981, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38838792

RESUMO

Obesity in adult females impairs fertility by altering oxidative stress, DNA repair and chemical biotransformation. Whether prepubertal obesity results in similar ovarian impacts is under-explored. The objective of this study was to induce obesity in prepubertal female mice and assess puberty onset, follicle number, and abundance of oxidative stress, DNA repair and chemical biotransformation proteins basally and in response to 7,12-dimethylbenz(a)anthracene (DMBA) exposure. DMBA is a polycyclic aromatic hydrocarbon that has been shown to be ovotoxic. Lactating dams (C57BL6J) were fed either a normal rodent containing 3.5% kCal from fat (lean), or a high fat diet comprised of 60% kCal from fat, and 9% kCal from sucrose. The offspring were weaned onto the diet of their dam and exposed at postnatal day 35 to either corn oil or DMBA (1 mg/kg) for 7 d via intraperitoneal injection. Mice on the HFD had reduced (P < 0.05) age at puberty onset as measured by vaginal opening but DMBA did not impact puberty onset. Heart, spleen, kidney, uterus and ovary weight were increased (P < 0.05) by obesity and liver weight was increased (P < 0.05) by DMBA exposure in obese mice. Follicle number was largely unaffected by obesity or DMBA exposure, with the exception of primary follicle number, which were higher (P < 0.05) in lean DMBA exposed and obese control relative to lean control mice. There were also greater numbers (P < 0.05) of corpora lutea in obese relative to lean mice. In lean mice, DMBA exposure reduced (P < 0.05) the level of CYP2E1, EPHX1, GSTP1, BRCA1, and CAT but this DMBA-induced reduction was absent in obese mice. Basally, obesity reduced (P < 0.05) the abundance of CYP2E1, EPHX1, GSTP1, BRCA1, SOD1 and CAT. There was greater (P < 0.05) fibrotic staining in obese DMBA-exposed ovaries and PPP2CA was decreased (P < 0.05) in growing follicles by both obesity and DMBA exposure. Thus, prepubertal obesity alters the capacity of the ovary to respond to DNA damage, ovotoxicant exposure and oxidative stress.

2.
Toxicol Appl Pharmacol ; 486: 116930, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38626870

RESUMO

Obesity impairs oocyte quality, fertility, pregnancy maintenance, and is associated with offspring birth defects. The model ovotoxicant, 7,12-dimethylbenz[a]anthracene (DMBA), causes ovarian DNA damage and follicle loss. Both DMBA-induced chemical biotransformation and the DNA damage response are partially attenuated in obese relative to lean female mice but whether weight loss could improve the DNA damage response to DMBA exposure has not been explored. Thus, at six weeks of age, C57BL/6 J female mice were divided in three groups: 1) Lean (L; n = 20) fed a chow diet for 12 weeks, 2) obese (O; n = 20) fed a high fat high sugar (HFHS) diet for 12 weeks and, 3) slim-down (S; n = 20). The S group was fed with HFHS diet for 7 weeks until attaining a higher body relative to L mice on week 7.5 and switched to a chow diet for 5 weeks to achieve weight loss. Mice then received either corn oil (CT) or DMBA (D; 1 mg/kg) for 7 d via intraperitoneal injection (n = 10/treatment). Obesity increased (P < 0.05) kidney and spleen weight, and DMBA decreased uterine weight (P < 0.05). Ovarian weight was reduced (P < 0.05) in S mice, but DMBA exposure increased ovary weight in the S mice. LC-MS/MS identified 18, 64, and 7 ovarian proteins as altered (P < 0.05) by DMBA in the L, S and O groups, respectively. In S and O mice, 24 and 8 proteins differed, respectively, from L mice. These findings support weight loss as a strategy to modulate the ovarian genotoxicant response.


Assuntos
9,10-Dimetil-1,2-benzantraceno , Dano ao DNA , Camundongos Endogâmicos C57BL , Obesidade , Ovário , Redução de Peso , Animais , Feminino , 9,10-Dimetil-1,2-benzantraceno/toxicidade , Obesidade/metabolismo , Dano ao DNA/efeitos dos fármacos , Redução de Peso/efeitos dos fármacos , Ovário/efeitos dos fármacos , Ovário/metabolismo , Ovário/patologia , Camundongos , Reparo do DNA/efeitos dos fármacos , Doenças Ovarianas/induzido quimicamente , Doenças Ovarianas/prevenção & controle , Doenças Ovarianas/metabolismo , Doenças Ovarianas/patologia , Dieta Hiperlipídica
3.
Toxicol Appl Pharmacol ; 474: 116614, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37422089

RESUMO

Obesity and overweight cause poor oocyte quality, miscarriage, infertility, polycystic ovarian syndrome, and offspring birth defects and affects 40% and 20% of US women and girls, respectively. Perfluorooctanoic acid (PFOA), a per- and poly-fluoroalkyl substance (PFAS), is environmentally persistent and has negative female reproductive effects including endocrine disruption, oxidative stress, altered menstrual cyclicity, and decreased fertility in humans and animal models. PFAS exposure is associated with non-alcoholic fatty liver disease which affects ∼24-26% of the US population. This study investigated the hypothesis that PFOA exposure impacts hepatic and ovarian chemical biotransformation and alters the serum metabolome. At 7 weeks of age, female lean, wild type (KK.Cg-a/a) or obese (KK.Cg-Ay/J) mice received saline (C) or PFOA (2.5 mg/Kg) per os for 15 d. Hepatic weight was increased by PFOA exposure in both lean and obese mice (P < 0.05) and obesity also increased liver weight (P < 0.05) compared to lean mice. The serum metabolome was also altered (P < 0.05) by PFOA exposure and differed between lean and obese mice. Exposure to PFOA altered (P < 0.05) the abundance of ovarian proteins with roles in xenobiotic biotransformation (lean - 6; obese - 17), metabolism of fatty acids (lean - 3; obese - 9), cholesterol (lean - 8; obese - 11), amino acids (lean - 18; obese - 19), glucose (lean - 7; obese - 10), apoptosis (lean - 18; obese - 13), and oxidative stress (lean - 3; obese - 2). Use of qRT-PCR determined that exposure to PFOA increased (P < 0.05) hepatic Ces1 and Chst1 in lean but Ephx1 and Gstm3 in obese mice. Also, obesity basally increased (P < 0.05) Nat2, Gpi and Hsd17b2 mRNA levels. These data identify molecular changes resultant from PFOA exposure that may cause liver injury and ovotoxicity in females. In addition, differences in toxicity induced by PFOA exposure occurs in lean and obese mice.


Assuntos
Fluorocarbonos , Fígado , Humanos , Adulto , Feminino , Camundongos , Animais , Camundongos Obesos , Caprilatos/toxicidade , Fluorocarbonos/toxicidade , Obesidade/metabolismo
4.
Mol Reprod Dev ; 90(7): 503-516, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36652419

RESUMO

Exposure to environmental toxicants and hyperthermia can hamper reproduction in female mammals including swine. Phenotypic manifestations include poor quality oocytes, endocrine disruption, infertility, lengthened time to conceive, pregnancy loss, and embryonic defects. The ovary has the capacity for toxicant biotransformation, regulated in part by the phosphatidylinositol-3 kinase signaling pathway. The impacts of exposure to mycotoxins and pesticides on swine reproduction and the potential for an emerging chemical class of concern, the per- and polyfluoroalkylated substances, to hamper porcine reproduction are reviewed. The negative impairments of heat stress (HS) on swine reproductive outcomes are also described and the cumulative effect of environmental exposures, such as HS, when present in conjunction with a toxicant is considered.


Assuntos
Resposta ao Choque Térmico , Reprodução , Gravidez , Animais , Suínos , Feminino , Ovário/metabolismo , Exposição Ambiental , Oócitos , Mamíferos
5.
Farm. comunitarios (Internet) ; 14(3): 5-14, julio 2022. tab
Artigo em Espanhol | IBECS | ID: ibc-209778

RESUMO

Introducción: según estudios recientes, los Servicios Profesionales Farmacéuticos Asistenciales (SPFA) demostraron sus beneficios en la calidad de vida de pacientes y sistemas de salud. Los SPFA son actividades sanitarias prestadas desde la farmacia comunitaria (FC) para la prevención de enfermedades y la mejora de la salud mediante la optimización del uso y del resultado de los tratamientos. Sin embargo, en España existe un bajo porcentaje de farmacias comunitarias que ofrecen SPFA, a excepción de la dispensación, indicación farmacéutica, medida de parámetros clínicos, la educación/información sanitaria y la formulación magistral, ya arraigados en la profesión desde hace tiempo. Objetivo: analizar los factores facilitadores y barreras en la demanda de determinados SPFA por parte de usuarios potenciales, desde el enfoque del producto según las 4Ps del Marketing Mix.Material y métodos: estudio cualitativo de tipo explicativo-interpretativo y exploratorio basado en la teoría fundamentada, mediante análisis inductivo aplicado a entrevistas semi-estructuradas, individuales y grupales.Resultados: las barreras y facilitadores son similares en todos los SPFA analizados, salvo algunas excepciones. Estas barreras y facilitadores son multifactoriales, porque están vinculados con la farmacia, el usuario, factores externos y el farmacéutico.Conclusiones: las barreras en la demanda de los SPFA son la baja adaptación a las necesidades del usuario, los nombres poco entendibles, la falta de integración de la FC en el sistema sanitario, el desconocimiento sobre los SPFA, las insuficientes evidencias de éxito y la satisfacción en servicios percibidos como similares realizados fuera de la FC. Por el contrario, los facilitadores que ayudan al aumento de la demanda de los SPFA son la actitud y aptitud del farmacéutico, el buen trato al paciente, la accesibilidad, cercanía y confortabilidad de la FC y la necesidad del paciente por mejorar su estado de salud. (AU)


Assuntos
Humanos , Atenção Primária à Saúde , Farmácia , Marketing , Sistemas de Saúde , Prevenção de Doenças , Terapêutica , Pacientes , Espanha
6.
Int J Pharm ; 614: 121415, 2022 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-34973409

RESUMO

A bioequivalence study comparing two fixed dose combination tablets containing 200 mg ibuprofen and 30 mg pseudoephedrine hydrochloride showed bioequivalence for pseudoephedrine AUC and Cmax, but the reference product showed higher Cmax than the test product in fasted conditions. The main difference between products was the presence of tribasic calcium phosphate in the reference tablet, resulting in an increased surface pH of the dissolving ibuprofen particles under gastric and intestinal conditions and, consequently, higher solubility of ibuprofen. A mechanistic model based on mass balance and ionization equilibria was used to calculate the pH of the particle surface under different buffer conditions. The discrepancies in surface pH between test and reference tablet were pronounced in 0.1 M and 0.01 M hydrochloric acid and in diluted maleate 7 mM pH 6.5 and phosphate 5 mM pH 6.7 buffers (but negligible in compendial phosphate buffer pH 6.8. Only those dissolution tests using pre-treatment in acidic conditions could be used to build a one-step in vitro-in vivo correlation (IVIVC). This work shows the potential of these discriminatory and in vivo predictive dissolution methods to obtain IVIVCs for BCS class IIa drugs and for extending BCS biowaivers to BCS class IIa drugs.


Assuntos
Ibuprofeno , Solubilidade , Comprimidos , Equivalência Terapêutica
7.
Biol Reprod ; 105(1): 278-289, 2021 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-33855340

RESUMO

Zearalenone (ZEN), a nonsteroidal estrogenic mycotoxin, is detrimental to female reproduction. Altered chemical biotransformation, depleted primordial follicles and a blunted genotoxicant response have been discovered in obese female ovaries, thus, this study investigated the hypothesis that obesity would enhance ovarian sensitivity to ZEN exposure. Seven-week-old female wild-type nonagouti KK.Cg-a/a mice (lean) and agouti lethal yellow KK.Cg-Ay/J mice (obese) received food and water ad libitum, and either saline or ZEN (40 µg/kg) per os for 15 days. Body and organ weights, and estrous cyclicity were recorded, and ovaries collected posteuthanasia for protein analysis. Body and liver weights were increased (P < 0.05) in the obese mice, but obesity did not affect (P > 0.05) heart, kidney, spleen, uterus, or ovary weight and there was no impact (P > 0.05) of ZEN exposure on body or organ weight in lean or obese mice. Obese mice had shorter proestrus (P < 0.05) and a tendency (P = 0.055) for longer metestrus/diestrus. ZEN exposure in obese mice increased estrus but shortened metestrus/diestrus length. Neither obesity nor ZEN exposure impacted (P > 0.05) circulating progesterone, or ovarian abundance of EPHX1, GSTP1, CYP2E1, ATM, BRCA1, DNMT1, HDAC1, H4K16ac, or H3K9me3. Lean mice exposed to ZEN had a minor increase in γH2AX abundance (P < 0.05). In lean and obese mice, LC-MS/MS identified alterations to proteins involved in chemical metabolism, DNA repair and reproduction. These data identify ZEN-induced adverse ovarian modes of action and suggest that obesity is additive to ZEN-induced ovotoxicity.


Assuntos
Micotoxinas/efeitos adversos , Ovário/metabolismo , Proteoma/metabolismo , Zearalenona/efeitos adversos , Animais , Estrogênios não Esteroides/efeitos adversos , Feminino , Camundongos , Ovário/efeitos dos fármacos
8.
Int J Pharm ; 557: 154-161, 2019 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-30594686

RESUMO

INTRODUCTION: There is no consensus on administering hyperosmolar formulations by mouth to neonates. In 1976, the Committee on Nutrition of the American Academy of Pediatrics published a recommendation of not administer formulations with an osmolarity higher than 400 mOsm/L due to the possible damage to intestine and relationship with necrotizing enterocolitis. Since this recommendation, exists a general trend of reducing osmolality of oral formulations without considering the pharmacokinetics of absorption of the drugs. The objective of this study was to characterize the permeability values of drugs formulated at different osmolalities by using a well-established rat intestinal perfusion model and to measure the osmolality of the most used formulations in our neonatology unit. METHODS: For the osmolality measurement study, most common used oral drugs were selected (compounded formulations and drug products). Osmolality of three dilutions (1:1, 1:4 and 1:8) were measured using a cryoscopic descent osmometer. Atenolol, caffeine, furosemide, hydrocortisone and paracetamol were selected for the permeability study. Three suspensions were elaborated of each drug (150 mOsm/kg, 300 mOsm/kg and 1500 mOsm/kg). Permeability values and absorption rate coefficients were determined in complete small intestine using in situ "closed loop" perfusion method. RESULTS: The formulations that resulted to be hyperosmolar (>400 mOsm/kg) were 86% (70% of these proved to be above 1500 mOsm/kg). The permeability study shown that the osmolality is inversely proportional to the apparent permeability of the drug in the studied drugs. The permeability values obtained with hyperosmolar samples were lower compared to 150 mOsm/kg or 300 mOsm/kg. CONCLUSIONS: Osmolality parameter is of particular relevance in oral drug administration in neonate because the risk of damaging the gastrointestinal tract and because of the risk that modifying osmolality also modifies its permeability, resulting in a potential change in bioavailability.


Assuntos
Absorção Intestinal , Concentração Osmolar , Administração Oral , Animais , Composição de Medicamentos , Masculino , Pediatria , Perfusão , Permeabilidade , Preparações Farmacêuticas/administração & dosagem , Preparações Farmacêuticas/química , Ratos Wistar
9.
Curr Top Med Chem ; 18(15): 1287-1303, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30277155

RESUMO

Giardia intestinalis infection causes enterocytes damage and loss of brush border of the epithelial cells of the intestine that leads to shortening of microvilli and altered epithelial barrier function. This pathology results in aqueous diarrhoea, steatorrhea, nausea, abdominal pain, vomiting and weight loss. However, most infections are asymptomatic. The main consequence of Giardia colonization is nutrients malabsorption. Several families of drugs with good efficacy are used for Giardia treatment, but sometime dosing regimens are suboptimal and emerging resistance begins to question their clinical value. Moreover, some of these drugs can cause side effects that result in patient discomfort and low adherence to the treatment. This paper reviews the drugs currently used for the treatment against Giardia: the mechanism of action, the efficacy, the normal dosing, side effects and in vitro and clinical studies. In addition, new therapies against Giardia such as those based on phytochemicals, Lactobacillus and nanotechnology are collected in this paper, trying to find the ideal treatment for this disease with maximum efficacy and minimum adverse effects.


Assuntos
Antiprotozoários/farmacologia , Giardia lamblia/efeitos dos fármacos , Giardíase/tratamento farmacológico , Antiprotozoários/química , Giardia lamblia/patogenicidade , Giardíase/microbiologia , Testes de Sensibilidade Parasitária
10.
Ann Glob Health ; 84(3): 334-337, 2018 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-30835399

RESUMO

Occupational health in Guatemala has come a long way. In 1958, the first Regulation of Occupational Health by the Guatemalan Social Security Institute was published. There wasn´t another Directive in the country regarding this issue until the year 2000, when the National Council for Occupational Safety and Health was created. In 2014, it published the Governmental Agreement 229-2014 Occupational Health and Safety Regulations, which came into force on September 8th, 2015. Nowadays there are other institutions that care about this topic. Some of these institutions promote occupational health training through courses, workshops, seminars, etc., but there is not a formal education program yet. There are some other institutions, such as the National Institute of Statistics, which generates information concerning employment, unemployment, characteristics, composition, structure, and functioning of the labor market through surveys. And finally, there are other institutions like the Health, Labor and Environment Program of Central America SALTRA, which promotes investigation in this topic, generates information as well as endorses training regarding occupational safety as an important issue in the country.


Assuntos
Academias e Institutos/história , Órgãos Governamentais/história , Saúde Ocupacional/história , Academias e Institutos/legislação & jurisprudência , Governo Federal , Órgãos Governamentais/legislação & jurisprudência , Guatemala , História do Século XX , História do Século XXI , Humanos , Saúde Ocupacional/educação , Saúde Ocupacional/legislação & jurisprudência , Saúde Ocupacional/tendências
12.
Data Brief ; 11: 221-224, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28243616

RESUMO

A long non-coding RNA called ANRIL located on chromosome 9p21.3 has been identified as a novel genetic factor associated with cardiovascular disease. Investigation of several single nucleotide polymorphisms (SNPs) of Noncoding Antisense RNA in the INK4 Locus (ANRIL) gene are of particular interest. This article reports data related to the research article entitled: "Association of ANRIL gene polymorphisms with major adverse cardiovascular events in hemodialysis patients" (Arbiol-Roca et al. [1]). Data presented show the genotypic distribution of four selected ANRIL SNPs: rs10757278, rs4977574, rs10757274 and rs6475606 in a cohort constituted by 284 hemodialysis patients. This article analyzes the Hardy-Weinberg disequilibrium of each studied SNP, and the linkage disequilibrium between them.

13.
Clin Chim Acta ; 466: 61-67, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28057453

RESUMO

BACKGROUND: Cardiovascular disease is the leading cause of death in patients with chronic kidney disease (CKD). Single nucleotide polymorphisms (SNPs) in ANRIL gene have been associated with higher cardiovascular morbidity and mortality in general population. The main objective was to ascertain whether ANRIL polymorphisms could identify risk of major adverse cardiovascular event (MACE) in patients starting on hemodialysis (HD). METHODS: This was a prospective observational cohort study. 284 CKD patients starting on HD were included in the study and followed until achievement of the primary end-point (MACE) or end of the study. All patients were genotyped for four ANRIL SNPs (rs10757278, rs4977574, rs10757274 and rs6475606). Kaplan-Meier curves and multivariate Cox survival analyses, together with multiple logistic regression were used to analyze the association between ANRIL SNPs and MACE. RESULTS: We found that ANRIL SNP rs10757278 was a representative SNP of a strong linkage disequilibrium block and showed significant genotypic associations with MACE in hemodialysis patients. Homozygous patients for the risk allele (GG) showed 2.17 (1.05-4.49) fold increased risk of MACE during hemodialysis than carriers of the protective allele (AA or AG). Diabetes mellitus was a strong enhancer of this effect. CONCLUSIONS: Our results indicate that ANRIL polymorphisms may confer risk to development of MACE in incident patients on hemodialysis.


Assuntos
Doenças Cardiovasculares/genética , Polimorfismo de Nucleotídeo Único/genética , RNA Longo não Codificante/genética , Insuficiência Renal Crônica/complicações , Idoso , Estudos de Coortes , Predisposição Genética para Doença , Genótipo , Humanos , Desequilíbrio de Ligação , Pessoa de Meia-Idade , Estudos Prospectivos , Diálise Renal
14.
Histol Histopathol ; 31(11): 1271-9, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27323848

RESUMO

Intravascular papillary endothelial hyperplasia (IPEH) is a reactive process of questioned pathogenesis (primary proliferation of endothelial cells/ECs versus organizing thrombi). The aim of this study is to assess the organization of morphologic patterns, with precise location of neovascularization and papillary distribution in IPEH to clarify the role of the vein wall (mainly vein intimal ECs) in lesion development and papillary formation. We studied 12 cases of IPEH in skin and subcutaneous veins by serial histological sections and immunohistochemical procedures. In four well-structured cases (the remaining cases showed overlapping events), we found four principal histological patterns organized by zone: 1) invaginated vein wall zone with microvascular networks. The intraparietal microvessels presented CD34+ and CD31+ ECs arising from ECs of the vein intima, and αSMA+ pericyte-like cells originating from modified SMCs of the media layer. 2) Papillary zone, generally with myriad papillae, formed by ECs of intraparietal microvessel networks encircling vein wall components (parietal papillae). 3) Organizing thrombotic zone from microvascular networks of invaginated vein wall zone. 4) Unorganized thrombotic zone partially covered by ECs, also originating from vein intimal endothelium and arranged in a monolayer or encircling thrombotic fibrin (thrombotic papillae). In conclusion, the capacity of vein intimal ECs and those originating from them (in newly-formed microvessels in the vein itself and covering the unorganized thrombi) to encircle vein wall components or fibrin, and to form papillae (ECs form the cover and encircled components the core) supports a piecemeal mode of angiogenesis as a pathogenic basis of IPEH. This mechanism encompasses the two histogenetic hypotheses outlined above.


Assuntos
Células Endoteliais/patologia , Endotélio Vascular/patologia , Neovascularização Patológica/patologia , Veias/patologia , Adolescente , Adulto , Idoso , Criança , Feminino , Humanos , Hiperplasia/patologia , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Adulto Jovem
15.
Soft Matter ; 10(44): 8875-87, 2014 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-25274139

RESUMO

We describe the synthesis and characterization of a family of diblock copolymers with 5 units of a dihexyloxy-phenylenevinylene block (OHPV) connected to a series of poly(ethylene glycol) (PEG) chains of different average lengths (12, 45 and 115 PEG units: OHPV5-b-PEG12, OHPV5-b-PEG45, OHPV5-b-PEG115). All three polymers underwent self-assembly in ethanol, a good solvent for the PEG units, but poor for the OHPV segment. The nature of the structures formed depends sensitively on the length of the PEG block. OHPV5-b-PEG115 formed long fiber-like micelles of uniform width, whereas OHPV5-b-PEG45 formed fragile broad ribbons. We also obtained thin ribbons with OHPV5-b-PEG12 but they tend to fold and twist upon themselves. The structures obtained were characterized by transmission electron microscopy (TEM) and atomic force microscopy (AFM), as well as by wide-angle X-ray scattering (WAXS) and differential scanning calorimetry (DSC). In addition, their photophysical properties were examined by UV-vis, steady state fluorescence and fluorescence decay measurements. The results of these experiments indicate that the OHPV groups pack differently in the fiber-like micelles of OHPV5-b-PEG115 than in the lamellar structures formed by OHPV5-b-PEG45.

16.
Chemistry ; 20(22): 6622-7, 2014 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-24740814

RESUMO

The ability of cyclodextrin-based polycationic cluster to undergo reversible DNA condensation and release in a physiologically useful pH window has been finely tuned by the installation of a capping xylylene moiety at the secondary face of the cyclooligosaccharide. This strategy can be exploited advantageously in the design of self-assembling nonviral gene-delivery systems from molecular entities.


Assuntos
Ciclodextrinas/química , DNA/química , Nanoestruturas/química , Animais , Células COS , Chlorocebus aethiops , Dicroísmo Circular , DNA/metabolismo , Dimerização , Concentração de Íons de Hidrogênio , Poliaminas/química , Polieletrólitos , Transfecção
17.
Food Chem ; 139(1-4): 1052-61, 2013 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-23561209

RESUMO

The postharvest dehydration is one of the most important steps in obtaining a high quality naturally sweet wine and it can play an important role in modulating the production and the release of volatile compounds. However, only a few studies have analysed the changes in the free and bound volatile compounds of grapes throughout the process. In this work, GC-MS was applied to determine the aromatic composition of Garnacha Tintorera grapes subjected to off-vine dehydration or raisining at several points during the process. The total water loss in 83 days was about 62% and the sugar concentration rose from 225 to 464 g/L. Within the free volatile compounds, isoamyl alcohols, benzaldehyde and guaiacol registered the largest increase above the concentration effect due to water loss; while within the bound volatile compounds were isoamyl alcohols, ethyl vanillate and benzoic acid. The aromatic profile of the raisins obtained were mainly caramelised, floral, phenolic and burned.


Assuntos
Vitis/química , Compostos Orgânicos Voláteis/análise , Vinho/análise , Frutas/química , Cromatografia Gasosa-Espectrometria de Massas , Odorantes/análise , Vitis/classificação , Vinho/classificação
18.
J Phys Chem B ; 117(18): 5472-85, 2013 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-23590313

RESUMO

The conformational properties and aggregation behavior of two selectively modified cyclomaltooligosaccharides (cyclodextrins, CDs) containing a double-linked 1,8-dimethylnaphthalene cap-like moiety at the secondary face, namely, 2(I),3(I)-O-(1,8-dimetylnaphthalene-α,α'-diyl)-per-O-Me-α- and -γ-cyclodextrins (NmαCD and NmγCD, respectively), in water and in organic solvents were investigated. Both CD derivatives self-associated in water to form dimer species, but the characteristics of the dimerization process and of the resulting dimer strongly depended on the size of the macrocycle. Dimerization constants, thermodynamic parameters upon association, and information about the preferred conformations of the monomer and dimer CD structures were obtained by using NMR, UV-vis, steady-state and time-resolved fluorescence, and circular dichroism experimental techniques, as well as molecular mechanics (MM) and molecular dynamics (MD) simulations. The complexation of 1,8-di(methoxymethyl)naphathalene (oNy) and the heteroassociation of both NmCDs with their permethylated CD partners (mCDs), lacking the aromatic cap, were examined. In addition, the influence of the size of the chromophore moiety on the thermodynamics of self-association was also assessed by comparison of the results obtained for the new naphthalene derivatives with those of the 2(I),3(I)-O-(1,2-xylylene)-modified CD analogues (XmCDs).


Assuntos
Ciclodextrinas/química , Naftalenos/química , Espectroscopia de Ressonância Magnética , Conformação Molecular , Simulação de Dinâmica Molecular , Tamanho da Partícula , Propriedades de Superfície , Termodinâmica
19.
Water Environ Res ; 84(2): 150-4, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22515065

RESUMO

A UV-Vis spectrophotometric method was developed as a preliminary approach to the determination of antimony in water samples from a river that flows very close to an abandoned mining site. The analyte is complexed with ammonium pyrrolidinedithiocarbamate and absorbance of the complex is measured at 291.06 nm. The standard additions method is mandatory in view of the matrix effect observed, and the response is linear at least up to 9.3 microg/mL of antimony. The sensitivity of the method is 2.609 x 10(-2) mL/microg, whereas the limits of detection and quantification are, respectively, 0.2 and 0.6 microg/mL. The repeatability, expressed as mean relative standard deviation of the measurements within the calibration range, is 2.0%, whereas the repeatability of the entire procedure is 0.3%. The mean analytical recovery within the calibration range was 102.6%. The method was successfully applied to river water samples.


Assuntos
Antimônio/química , Mineração , Rios/química , Poluentes Químicos da Água/química , Espanha , Espectrofotometria Ultravioleta/métodos
20.
Food Chem ; 134(4): 2313-25, 2012 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-23442690

RESUMO

The aroma profiles obtained of three Garnacha Tintorera-based wines were studied: a base wine, a naturally sweet wine, and a mixture of naturally sweet wine with other sweet wine obtained by fortification with spirits. The aroma fingerprint was traced by GC-MS analysis of volatile compounds and by sensorial analysis of odours and tastes. Within the volatiles compounds, sotolon (73 µg/L) and acetoin (122 µg/L) were the two main compounds found in naturally sweet wine. With regards to the odorant series, those most dominant for Garnacha Tintorera base wine were floral, fruity and spicy. Instead, the most marked odorant series affected by off-vine drying of the grapes were floral, caramelized and vegetal-wood. Finally, odorant series affected by the switch-off of alcoholic fermentation with ethanol 96% (v/v) fit for human consumption followed by oak barrel aging were caramelized and vegetal-wood. A partial least square test (PLS-2) was used to detect correlations between sets of sensory data (those obtained with mouth and nose) with the ultimate aim of improving our current understanding of the flavour of Garnacha Tintorera red wines, both base and sweet. Based on the sensory dataset analysis, the descriptors with the highest weight for separating base and sweet wines from Garnacha Tintorera were sweetness, dried fruit and caramel (for sweet wines) vs. bitterness, astringency and geranium (for base wines).


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Vitis/química , Compostos Orgânicos Voláteis/análise , Vinho/análise , Humanos , Odorantes/análise , Paladar
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