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2.
Asian Pac J Cancer Prev ; 23(6): 1913-1920, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35763631

RESUMO

BACKGROUND: This study was designed to evaluate the effect of different concentrations of conjugated equine estrogens (CEE) on the ovarian epithelium of female CD1 mice. METHODS: Twenty-four female mice at 7 months with irregular estrus cycles were randomly divided into four groups of 6 mice each. Group one was considered as a control group and received a daily dose of 0.5ml of propylene glycol, for three weeks, while those in the treatment groups received a daily dose of 14µg/kg, 28µg/kg and 56µg/kg conjugated equine estrogens, respectively. RESULTS: The results from this study showed a strong correlation between elevated concentrations of CEE and histological changes in ovarian surface epithelium (OSE). They also showed that administration of high-dose estrogen created the conditions for excessive proliferation of OSE which may progress into the development of cysts in the ovaries. CONCLUSION: This study concluded that high concentrations of CEE may increase the chances of developing epithelial ovarian cancer.


Assuntos
Estrogênios Conjugados (USP) , Ovário , Animais , Modelos Animais de Doenças , Epitélio , Estrogênios/farmacologia , Estrogênios Conjugados (USP)/farmacologia , Estrogênios Conjugados (USP)/uso terapêutico , Feminino , Camundongos
3.
Vet World ; 14(3): 709-720, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33935417

RESUMO

BACKGROUND AND AIM: Meat is a rich source of many nutrients and plays a vital role in human life however, meat safety is one of the top priorities of great concern for consumers today. More than 90% of human exposure to harmful materials is due to consumption of contaminated meat products. This study was designed to compare four valid analytical methods for the determination of organochlorine pesticides 2,4 D (2,4-dichlorophenoxyacetic acid), dichlorodiphenyldichloroethylene/dichlorodiphenyltrichloroethane, alachlor, organophosphate, anabolic steroids (progesterone, testosterone, and estrogen), antibiotics (tetracycline, sulfonamides, gentamycin, and cephalexin), antibacterial compounds (Macrolide, ß-Lactam, Chloramphenicol, Sulphur drugs, and Gentamicin) residues in 135 beef, buffalo, and sheep meat samples (fresh, frozen meats, minced, and sausage samples) of local, regional, and international brands available in Omani markets. MATERIALS AND METHODS: Triplicate meat samples from each brand within each species were extracted with acetonitrile and purified with acetonitrile-saturated n-hexane to remove all impurities. To dry the sample after heating, the residue was passed across a Sep-Pak C18 cartridge for sample cleaning before gas chromatography (GC) (Brand GCMS-QP2010 Plus) coupled with different detectors, including a mass spectrometer or GC-electron capture detector (GC-ECD). Liquid chromatography/mass spectrometry (LC-MS) was also employed for the quantification of the residues in meat products. Enzyme-linked immunosorbent assay (ELISA) kits were employed to assess veterinary drug residues, anabolic steroids, and pesticides. The CHARM II instrument was employed to detect chloramphenicol, gentamicin, sulfa-drug, ß-lactam, and macrolide residues in meat and meat product samples. RESULTS: A thin-layer chromatographic (TLC) method should be considered as another method of choice to determine concentrations of veterinary drugs and anabolic steroids. The TLC results were validated by LC-MS. The three described methods permit the multi-residue analysis of anabolic steroid residue levels of 0.06-1.89 ppb in meat product samples. There were three violative residues of anabolic steroids in red meat products that were above the maximum residue limits (MRLs). Although, the levels of organochlorine pesticides and antibiotic concentrations in meat products were below the MRLs, the long-term consumption is considered a health hazard and will affect the wellbeing of consumers. CONCLUSION: The four techniques (GC, high-performance liquid chromatography, ELISA and CHARM II) provided results that were reliable and precise for the detection of chessssmical residues in meat and meat products.

4.
Int. j. morphol ; 39(1): 318-326, feb. 2021. ilus
Artigo em Inglês | LILACS | ID: biblio-1385294

RESUMO

SUMMARY: In this study the consequences of prenatal exposure to tobacco smokes on the histo-morphological changes of cerebellum was assessed by comparing the smoker mice to the nonsmoker mice. A total of 30 pregnant cd-1 mice were divided into three groups of 10 mice each and with two replicates per group (5 mice each). Following acclimation for five days, the mice were placed in a special modified smoking machine for 2 hours per day over a two- and three-week period for group two and group three, respectively. Group one was considered as a control group. Mice in the control group were exposed simultaneously to fresh air from the room, while those in the treatment groups were exposed to tobacco smoke from six commercial filter cigarettes, containing 0.8 mg of nicotine, 10 mg of tar, and 10 mg of carbon monoxide, for three 1-hour exposure periods every day for three weeks. The mice in the control group were exposed to room air for three 1-hour periods every day for the same period of three weeks. The results from this study showed a correlation between maternal smoking and histological changes in Neuron purkinjense (Purkinje cells) of the cerebellum. They also showed that prenatal smoking period may have caused more damage in the histology and structure of Neuron purkinjense in some juvenile mice. An increased incidence of morphology damage of the cerebellum's Neuron purkinjense' structures was also observed in fetuses with prolonged exposure to tobacco smoking. Exposure of in utero maternal smoking may interfere with brain biological development parameters, giving rise to structural abnormalities of the cerebellum. This study concluded that tobacco smoke exposure to pregnant mice may affect neurodevelopment which may induce behavioural changes as a result of reduced cerebellar size and function.


RESUMEN: Se evaluaron los efectos producidos por la exposición prenatal al humo de tabaco en ratones expuestos y no expuestos y los cambios histomorfológicos observados en el cerebelo en ambos grupos. Un total de 30 ratones cd-1 preñados se dividieron en tres grupos de 10 ratones cada uno y con dos réplicas por grupo (5 ratones cada uno). Después de la aclimatación durante cinco días, los ratones se colocaron en una máquina de fumar modificada, especial durante 2 horas al día, durante un período de dos y tres semanas para el grupo dos y el grupo tres, respectivamente. El grupo uno se consideró como grupo control. Los ratones del grupo de control fueron expuestos simultáneamente al aire limpio de la habitación, mientras que los grupos de tratamiento fueron expuestos al humo de tabaco de seis cigarrillos comerciales, que contenían 0,8 mg de nicotina, 10 mg de alquitrán y 10 mg de monóxido de carbono. durante tres períodos de 1 hora diariamente, durante tres semanas. Los ratones del grupo de control se expusieron al aire ambiente durante tres períodos de 1 hora todos los días durante el mismo período de tres semanas. Los resultados de este estudio mostraron una correlación entre el tabaquismo materno y los cambios histológicos en las neuronas purkinjenses (células de Purkinje). Se observó además que el período de tabaquismo prenatal puede haber causado mayor daño en la histología y estructura de las neuronas purkinjenses en algunos ratones jóvenes. También se observó una mayor incidencia de daño morfológico de las estructuras de las neuronas purkinjenses del cerebelo en fetos con exposición prolongada al tabaquismo. La exposición al tabaquismo materno en el útero puede interferir con los parámetros de desarrollo biológico del cerebro, dando lugar a anomalías estructurales del cerebelo. Este estudio concluyó que la exposición al humo del tabaco en ratones preñados puede afectar el desarrollo neurológico, lo que puede inducir cambios de comportamiento como resultado de la reducción del tamaño y la función del cerebelo.


Assuntos
Animais , Feminino , Gravidez , Poluição por Fumaça de Tabaco/efeitos adversos , Cerebelo/efeitos dos fármacos , Efeitos Tardios da Exposição Pré-Natal , Células de Purkinje/efeitos dos fármacos , Exposição Materna/efeitos adversos
5.
Sci Rep ; 9(1): 19788, 2019 12 24.
Artigo em Inglês | MEDLINE | ID: mdl-31874969

RESUMO

Alkalinity is a known threat to crop plant growth and production, yet the role of exogenous silicon (Si) and salicylic acid (SA) application has been largely unexplored. Here, we sought to understand the beneficial impacts of Si and SA on tomato seedlings during high-pH (9.0) stress. Results showed that Si- and SA-treated plants displayed higher biomass, chlorophyll contents, relative leaf water and better root system than none-treated plants under alkaline conditions. Both Si and SA counteracted the alkaline stress-induced oxidative damage by lowering the accumulation of reactive oxygen species and lipid peroxidation. The major antioxidant defence enzyme activities were largely stimulated by Si and SA, and these treatments caused significantly increased K+ and lowered Na+ concentrations in shoot and root under stress. Moreover, Si and SA treatments modulated endogenous SA levels and dramatically decreased abscisic acid levels in both shoot and root. Additionally, key genes involved in Si uptake, SA biosynthesis, the antioxidant defence system and rhizosphere acidification were up-regulated in Si and SA treatments under alkaline conditions. These results demonstrate that Si and SA play critical roles in improving alkaline stress tolerance in tomato seedlings, by modifying the endogenous Na+ and K+ contents, regulating oxidative damage and key genes and modulating endogenous hormone levels. These findings will help to broaden our understanding regarding the physiological and molecular mechanisms associated with the alkaline soil tolerance in plants.


Assuntos
Ácido Salicílico/farmacologia , Silício/farmacologia , Solanum lycopersicum/fisiologia , Ácido Abscísico/química , Antioxidantes/química , Biomassa , Clorofila/química , Clorofila A/química , Concentração de Íons de Hidrogênio , Peroxidação de Lipídeos , Estresse Oxidativo , Folhas de Planta/química , Raízes de Plantas , Brotos de Planta , Rizosfera , Plântula , Solo , Estresse Fisiológico/efeitos dos fármacos
6.
Nanomedicine (Lond) ; 14(21): 2783-2798, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31617445

RESUMO

Aim: Acetyl-11-keto-ß-boswellic acid (AKBA) is a potent anti-inflammatory compound limited by its low water solubility and bioavailability. To load AKBA on silver nanoparticles (AgNPs) to improve bioavailability and water solubility of the compound. Materials & methods: AKBA-AgNPs were chemically synthesized and characterized by UV-Vis spectrophotometry, Fourier transform infrared spectroscopy, scanning electron microscopy and transmission electron microscopy. AKBA and AKBA-Ag were studied for their sedative-hypnotic and anti-inflammatory efficacies. Results: Pretreatment with AKBA or AKBA-Ag caused significant dose-dependent sedative-hypnotic effects at 5 and 10 mg/kg intraperitoneal. The effects of AKBA-loaded AgNPs caused pronounced changes in mice compared with those of AKBA, and the AKBA-AgNPs demonstrated anti-inflammatory effects that were superior to those of AKBA. Conclusion: The loading of AKBA on nanoparticles improved its pharmacokinetic effects, and capacity for drug delivery.


Assuntos
Anti-Inflamatórios/química , Portadores de Fármacos/química , Hipnóticos e Sedativos/química , Nanopartículas Metálicas/química , Prata/química , Triterpenos/química , Animais , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/farmacocinética , Boswellia/química , Liberação Controlada de Fármacos , Estabilidade de Medicamentos , Hipnóticos e Sedativos/administração & dosagem , Hipnóticos e Sedativos/farmacocinética , Masculino , Camundongos , Extratos Vegetais/química , Extratos Vegetais/farmacocinética , Sono/efeitos dos fármacos , Resultado do Tratamento , Triterpenos/administração & dosagem , Triterpenos/farmacocinética
7.
Int J Mol Sci ; 19(12)2018 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-30572617

RESUMO

In healthy or pathological brains, the neuroinflammatory state is supported by a strong communication involving microglia and neurons. Recent studies indicate that extracellular vesicles (EVs), including exosomes and microvesicles, play a key role in the physiological interactions between cells allowing central nervous system (CNS) development and/or integrity. The present report used medicinal leech CNS to investigate microglia/neuron crosstalk from ex vivo approaches as well as primary cultures. The results demonstrated a large production of exosomes from microglia. Their incubation to primary neuronal cultures showed a strong interaction with neurites. In addition, neurite outgrowth assays demonstrated microglia exosomes to exhibit significant neurotrophic activities using at least a Transforming Growth Factor beta (TGF-ß) family member, called nGDF (nervous Growth/Differentiation Factor). Of interest, the results also showed an EV-mediated dialog between leech microglia and rat cells highlighting this communication to be more a matter of molecules than of species. Taken together, the present report brings a new insight into the microglia/neuron crosstalk in CNS and would help deciphering the molecular evolution of such a cell communication in brain.


Assuntos
Sistema Nervoso Central/metabolismo , Exossomos/metabolismo , Hirudo medicinalis/fisiologia , Microglia/metabolismo , Neurônios/metabolismo , Sequência de Aminoácidos , Animais , Sistema Nervoso Central/efeitos dos fármacos , Técnicas de Cocultura , Exossomos/efeitos dos fármacos , Exossomos/ultraestrutura , Microglia/efeitos dos fármacos , Fatores de Crescimento Neural/farmacologia , Neuritos/efeitos dos fármacos , Neuritos/metabolismo , Neurônios/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
8.
PLoS One ; 13(6): e0198666, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29912889

RESUMO

The distribution and biosynthesis of boswellic acids (BAs) is scarce in current literature. Present study aims to elucidate the BAs biosynthetic and its diversity in the resins of Boswellia sacra and Boswellia papyrifera. Results revealed the isolation of new (3ß, 11ß-dihydroxy BA) and recently known (as new source, ß-boswellic aldehyde) precursors from B. sacra resin along with α-amyrin. Following this, a detailed nomenclature of BAs was elucidated. The quantification and distribution of amyrins (3-epi-α-amyrin, ß-amyrin and α-amyrin) and BAs in different Boswellia resins showed highest amyrin and BAs in B. sacra as compared with B. serrata and B. papyrifera. Distribution of BAs significantly varied in the resin of B. sacra collected from dry mountains than coastal trees. In B. sacra, high content of α-amyrin was found in the roots but it lacked ß-amyrin and BAs. The leaf part showed traces of ß-ABA and AKBA but was deficient in amyrins. This was further confirmed by lack of transcript accumulation of amyrin-related biosynthesis gene in leaf part. In contrast, the stem showed presence of all six BAs which are attributed to existence of resin-secretory canals. In conclusion, the boswellic acids are genus-specific chemical constituents for Boswellia species albeit the variation of the amounts among different Boswellia species and grades.


Assuntos
Boswellia/metabolismo , Triterpenos/metabolismo , Estrutura Molecular , Ácido Oleanólico/análogos & derivados , Ácido Oleanólico/metabolismo , Caules de Planta/ultraestrutura , Pró-Fármacos/isolamento & purificação , Pró-Fármacos/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Resinas Vegetais/metabolismo , Triterpenos/isolamento & purificação
9.
Gen Comp Endocrinol ; 187: 23-31, 2013 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-23524273

RESUMO

The annual testicular cycle of the house gecko Hemidactylus flaviviridis in Oman was studied. Plasma testosterone (T), estradiol (E2) and progesterone (P) concentrations were measured using a sensitive HPLC-MS/MS detection technique. The ultrastructural steroidogenic features in Sertoli and Leydig cells, which were the major source of steriodogenesis, were examined, using transmission electron microscopy (TEM). In addition, progesterone receptors (PR) were examined throughout the testicular cycle, using an immunohistochemical technique. The steroidogenic ultrastructural features were characterized by the presence of smooth endoplasmic reticulum (SER) in the form of cisternal whorls and tubular cisternae, presence of swollen vesiculated mitochondria, and association between SER, mitochondria and lipid droplets. The rise in plasma steroid concentrations was closely associated with the development of the ultrastructural features and PR expression in Leydig and Sertoli cells. During the active phase (November-May), there was a significant rise in plasma steroid concentrations (P<0.05) related to well developed steroidogenic features and strongly expressed PR. During the quiescent phase (June-August) there was a significant decline in plasma steroid concentrations, undeveloped steroiodogenic features and weakly expressed PR. The Renal Sexual Segment (RSS) was fully developed during the active phase. The data provides strong evidence that these ultrastructural steroidogenic features were related to the plasma sex steroid concentrations during the testicular cycle.


Assuntos
Lagartos/sangue , Lagartos/fisiologia , Receptores de Progesterona/metabolismo , Reprodução/fisiologia , Animais , Cromatografia Líquida de Alta Pressão , Estradiol/sangue , Imuno-Histoquímica , Células Intersticiais do Testículo/ultraestrutura , Lagartos/metabolismo , Masculino , Microscopia Eletrônica de Transmissão , Omã , Progesterona/sangue , Células de Sertoli/ultraestrutura , Testosterona/sangue
10.
ISRN Obes ; 2013: 342802, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24533222

RESUMO

The association of abdominal obesity with cardiovascular risk is often linked to altered secretion of adipose-derived factors and an abnormal lipid profile including formation of atherogenic small dense low density lipoprotein particles (sdLDL). Acylation-stimulating protein (ASP) is an adipose-derived hormone that exhibits potent lipogenic effects. Plasma ASP levels increase in obesity; however, the association of ASP levels with body fat distribution is not yet established, and no study to date has investigated the association of ASP with LDL size. In this study, we examined the association of ASP levels with abdominal obesity measures and the lipid profile including LDL size in 83 men with a wide range of abdominal girths. Regression analysis showed that waist/hip ratio was the main predictor of ASP levels ( ß = 0.52, P < 0.0001), significantly followed by decreased LDL size. BMI and TG levels, although positively correlated with ASP levels, were excluded as significant predictors in regression analysis. No correlation was found with LDL-C or apoB levels. ASP levels were 62.5% higher in abdominally obese compared to nonobese men. Waist/hip ratio presenting as the main predictor of ASP levels, suggests increased ASP production by abdominal fat which, as proposed previously, may result from resistance to ASP function causing delayed TG clearance and subsequent formation of atherogenic sdLDL.

11.
Planta Med ; 78(18): 1918-26, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23115018

RESUMO

Dendrophthoe falcata is a hemiparasitic plant commonly used for ailments such as ulcers, asthma, impotence, paralysis, skin diseases, menstrual troubles, pulmonary tuberculosis, and wounds. In this context, the validations of the traditional claim that the leaf extract of D. falcata possesses antibiofilm and anti-quorum sensing activity against different bacterial pathogens were assessed. The bacterial biofilms were quantified by crystal violet staining. Among the 17 bacterial pathogens screened, the methanolic fraction of the leaf extract clearly demonstrated antibiofilm activity for Proteus mirabilis, Vibrio vulnificus, Aeromonas hydrophila, Shigella sonnei, Chromobacterium violaceum ATCC 12472, Vibrio parahaemolyticus, Vibrio harveyi, Vibrio alginolyticus, Vibrio cholerae, and Proteus vulgaris. At biofilm inhibitory concentrations, biofilm formation was reduced by up to 70-90 %. Furthermore, the potential quorum-sensing activity of the leaf extract was tested by agar well diffusion using Chromobacterium violaceum (ATCC 12472 & CV O26) reporter strains. The inhibition of violacein production may be due to direct or indirect interference on QS by active constituents or the interactive effect of different phytocompounds present in the extracts. This is the first report on antibiofilm and QS activity of D. falcata leaf extracts, signifying the scope for development of complementary medicine for biofilm-associated infections.


Assuntos
Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Loranthaceae/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Percepção de Quorum/efeitos dos fármacos , Aeromonas hydrophila/efeitos dos fármacos , Chromobacterium/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Medicina Tradicional , Proteus mirabilis/efeitos dos fármacos , Proteus vulgaris/efeitos dos fármacos , Pseudomonas aeruginosa/efeitos dos fármacos , Shigella sonnei/efeitos dos fármacos , Vibrio alginolyticus/efeitos dos fármacos , Vibrio cholerae/efeitos dos fármacos , Vibrio parahaemolyticus/efeitos dos fármacos , Vibrio vulnificus/efeitos dos fármacos
12.
Cell Physiol Biochem ; 29(1-2): 163-70, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22415085

RESUMO

Inhaled ultrafine (nano) particles can translocate into the bloodstream and interact with circulatory cells causing systemic and cardiovascular events. To gain more insight into this potential mechanism, we studied the interaction of diesel exhaust particles (DEP) with human, rat and mouse erythrocytes in vitro. Incubation of erythrocytes with DEP (1, 10 or 100 µg/ml) for 30 min caused the highest hemolytic effect (up to 38%) in rats, compared to small but significant hemolysis in mice (up to 2.5%) and humans (up to 0.7%). Transmission electron microscopy of erythrocytes revealed the presence of variable degrees of ultrafine (nano)-sized aggregates of DEP either internalized and/or adsorbed onto the erythrocytes in the three species. A significant amount of DEP was found in rat and mouse (but not human) erythrocytes. Lipid erythrocyte susceptibility to in vitro peroxidation measured by malondialdehyde showed a significant and dose-dependent increase in erythrocytes of rats, but not humans or mice. Unlike in human erythrocytes, total antioxidant status (TAS) and superoxide dismutase (SOD) activity in rats were significantly and dose- dependently decreased. In mouse erythrocytes, DEP caused a decreased in SOD (at 10 µg/ml) and TAS (at 100 µg/ml) activities. In conclusion, DEP caused species-dependent erythrocyte hemolysis and oxidative stress, and were either taken up and/or adsorbed onto the red blood cells. Rat (and to a lesser degree mouse) erythrocytes were susceptible to DEP. Human erythrocytes showed the highest resistance to the observed effects. These species difference should be noted when using rats and mice blood as models for humans.


Assuntos
Eritrócitos/efeitos dos fármacos , Emissões de Veículos/toxicidade , Adulto , Animais , Eritrócitos/enzimologia , Eritrócitos/metabolismo , Hemólise/efeitos dos fármacos , Humanos , Masculino , Malondialdeído/metabolismo , Camundongos , Microscopia Confocal , Pessoa de Meia-Idade , Nanopartículas/química , Nanopartículas/toxicidade , Ratos , Ratos Wistar , Superóxido Dismutase/metabolismo
13.
Toxicology ; 279(1-3): 167-75, 2011 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-21073913

RESUMO

Nanomaterials are extensively used in medicines, industry and daily life, but little is known about their possible health effects. Titanium dioxide (TiO2) nonmaterial-based photocatalysis is useful in the complete mineralization of organic pollutants in waste water and air. While the Fe-doping of TiO2 enhances their photocatalytic activity, their potential pathophysiologic effects are unknown. Here, rutile Fe-doped (9%) pure titanium dioxide (TiO2) nanorods were prepared and characterized. Subsequently, we assessed the acute (24 h) pulmonary and extrapulmonary effects of intratracheal (i.t.) instillation of these nanorods (1 and 5 mg/kg) in Wistar rats. In the bronchoalveolar lavage, the treatment induced a significant and dose-dependent increase of neutrophils, an increase of interleukin-6 (IL-6, at 5 mg/kg), and caused a dose-dependent-decrease of superoxide dismutase (SOD) activity. The lung sections of rats exposed to rutile Fe-TiO2 nanorods showed infiltration of inflammatory cells in dose-dependent manner. Similarly, the heart rate, systolic blood pressure, plasma IL-6, and leukocyte and platelet numbers were increased at 5 mg/kg. The plasma SOD and reduced glutathaione activities were dose-dependently decreased after exposure to the nanorods. Histopathologically, the liver showed mild inflammatory cells infiltration of few portal tracts, but the kidneys and heart were unaffected. In plasma, the levels of lactate dehydrogenase and hepatic enzymes, i.e., alanine aminotranferease and aspartate aminotransferase were increased significantly. The in vitro exposure of human lung cancer cells NCI-H460-Luc2 and human hepatoma cells HepG2 to FeTiO2 (6.25-100 µg/ml) dose-dependently reduced cellular viability. Also, the In vitro direct addition of these nanorods (0.1-1 µg/ml) to untreated rat blood, significantly and dose-dependently induced platelet aggregation. In conclusion, exposure to rutile Fe-TiO2 promotes pulmonary and systemic inflammation and oxidative stress. It affects the liver, enhances thrombotic potential, heart rate and systolic blood pressure. Moreover, the rutile Fe-TiO2 elicited direct toxicity on NCI-H460-Luc2 and HepG2 cells.


Assuntos
Ferro/química , Fígado/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Titânio/toxicidade , Animais , Líquido da Lavagem Broncoalveolar , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Células Hep G2 , Humanos , Inflamação/induzido quimicamente , Inflamação/patologia , Interleucina-6/metabolismo , Fígado/metabolismo , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Nanotubos , Neutrófilos/metabolismo , Ratos , Ratos Wistar , Superóxido Dismutase/efeitos dos fármacos , Superóxido Dismutase/metabolismo , Titânio/administração & dosagem , Titânio/química
14.
Anim Sci J ; 81(3): 352-61, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20597893

RESUMO

The effects of transportation and electrical stimulation (90 V) on physiological, histochemical and meat quality characteristics of two breeds of Omani goats were assessed. Twenty 1-year-old male goats from each breed (Batina and Dhofari) were divided into two groups: 3 h transported during the hot season (42 degrees C day time temperature) and non-transported. Animals were blood-sampled before loading and prior to slaughter. Electrical stimulation was applied 20 min postmortem to 50% randomly selected carcasses of both breeds. Temperature and pH decline of the Longissimus was monitored. Ultimate pH, shear force, sarcomere length, myofibrillar fragmentation index, expressed juice, cooking loss and colour were measured from samples of Longissimus dorsi muscles. Electrical stimulation and transportation had a significant effect on most biochemical and meat quality characteristics of Longissimus dorsi. The transported goats had higher plasma cortisol (P < 0.01), adrenaline, nor-adrenaline and dopamine concentrations (P < 0.05) than non-transported goats. Electrical stimulation resulted in a significantly (P < 0.05) more rapid muscle pH fall during the first 12 h after slaughter. Muscles from electrically-stimulated carcasses had significantly (P < 0.05) longer sarcomeres, lower shear force value, a lighter colour (higher L* value), higher expressed juice and myofibrillar fragmentation index than those from non-stimulated ones. Meat from transported goats had significantly higher pH, expressed juice and shear force, but contained significantly lower sarcomere length and L* values than non-transported goats. The proportion of the myosin ATPase staining did not change as a function of stimulation, transportation or breed. These results indicated that subjecting goats to transportation for 3 h under high ambient temperatures can generate major physiological and muscle metabolism responses. Electrical stimulation improved quality characteristics of meat from both groups. This indicates that electrical stimulation may reduce detrimental effects of transportation on meat quality of Omani goats.


Assuntos
Cabras/fisiologia , Temperatura Alta , Carne , Músculo Esquelético/fisiologia , Estresse Fisiológico/fisiologia , Meios de Transporte , Animais , Estimulação Elétrica , Histocitoquímica , Masculino , Músculo Esquelético/metabolismo , Estações do Ano
15.
Mar Pollut Bull ; 58(5): 720-5, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19185323

RESUMO

Sea turtles migrate to various habitats where they can be exposed to different pollutants. Bacteria were collected from turtle eggs and their resistance to antibiotics was used as pollutant bio-indicators of contaminated effluents. Eggs were collected randomly from turtles when they were laying their eggs. A total of 90 eggs were collected and placed into sterile plastic bags (3 eggs/turtle) during June-December of 2003. The bacteria located in the eggshell, albumen and yolk were examined, and 42% of the eggs were contaminated with 10 genera of bacteria. Pseudomonas spp. were the most frequent isolates. The albumen was found to be the part of the egg to be the least contaminated by bacterial infection. Bacterial isolates tested with 14 antibiotics showed variations in resistance. Resistance to ampicillin was the highest. The presence of antibiotic resistant bacteria in eggs indicates that the green turtle populations were subjected to polluted effluents during some of their migratory routes and feeding habitats. Scanning electron microscopy revealed that Salmonella typhimurium penetrated all eggshell layers.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Bactérias/isolamento & purificação , Tartarugas/microbiologia , Tartarugas/fisiologia , Zigoto/microbiologia , Animais , Exposição Ambiental , Oceano Índico , Oceanos e Mares , Pseudomonas/isolamento & purificação , Salmonella typhimurium/isolamento & purificação , Salmonella typhimurium/fisiologia , Salmonella typhimurium/ultraestrutura , Poluentes Químicos da Água/análise
16.
J Agric Food Chem ; 55(6): 2459-66, 2007 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-17316022

RESUMO

Continuing an investigation on the fundamentals and applications of a recently proposed concept, i.e., the mechanical or network glass transition temperature, we now report data on the macrostructural changes in dehydrated apple tissue in relation to apparent porosity. Care was taken to keep the moisture content of the matrix constant (approximately 81%) while the volume fraction of total pores ranged from 0.38 to 0.79. Reproducible mechanical profiles identified the first derivative of shear storage modulus as a function of temperature to be the appropriate indicator of the mechanical Tg at the conjunction of the William-Landel-Ferry/free volume theory and the modified Arrhenius equation. Information on the microstructural characteristics and morphology of porous apple preparations was also made available via modulated differential scanning calorimetry and scanning electron microscopy. The work reveals and discusses discrepancies in the Tg-porosity relationship obtained from calorimetry and mechanical analysis attributable to the different extent to which the two techniques respond to degrees of molecular mobility.


Assuntos
Frutas/química , Malus/química , Varredura Diferencial de Calorimetria , Vidro , Mecânica , Microscopia Eletrônica de Varredura , Transição de Fase , Termodinâmica
17.
Am J Physiol Lung Cell Mol Physiol ; 292(3): L664-70, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17085524

RESUMO

Pollution by particulates has consistently been associated with increased cardiorespiratory morbidity and mortality. It has been suggested that ultrafine particles, of which diesel exhaust particles (DEP) are significant contributors, are able to translocate from the airways into the bloodstream in vivo. In the present study, we assessed the effect of systemic administration of DEP on cardiovascular and respiratory parameters. DEP were administered into the tail vein of rats, and heart rate, blood pressure, blood platelet activation, and lung inflammation were studied 24 h later. Doses of 0.02, 0.1, or 0.5 mg DEP/kg (8, 42, or 212 microg DEP/rat) induced a significant decrease of heart rate and blood pressure compared with saline-treated rats. Although the number of platelets was not affected, all the doses of DEP caused a shortening of the bleeding time. Similarly, in addition to triggering lung edema, the bronchoalveolar lavage analysis revealed the presence of neutrophil influx in DEP-treated rats in a dose-dependent manner. We conclude that the presence of DEP in the systemic circulation leads not only to cardiovascular and haemostatic changes but it also triggers pulmonary inflammation.


Assuntos
Doenças Cardiovasculares/induzido quimicamente , Coração/efeitos dos fármacos , Pulmão/efeitos dos fármacos , Pneumonia/induzido quimicamente , Emissões de Veículos/toxicidade , Animais , Tempo de Sangramento , Pressão Sanguínea/efeitos dos fármacos , Doenças Cardiovasculares/patologia , Contagem de Eritrócitos , Frequência Cardíaca/efeitos dos fármacos , Contagem de Leucócitos , Masculino , Pneumonia/patologia , Edema Pulmonar/induzido quimicamente , Edema Pulmonar/patologia , Ratos , Ratos Endogâmicos WKY
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