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1.
J Anim Physiol Anim Nutr (Berl) ; 104(1): 196-203, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31701584

RESUMO

The present experiment was conducted to evaluate the effect of dietary supplementation with some feed additives (potassium sorbate; Sor, hydrated sodium calcium almuniosilicate; Hsc and L-methionine; L-M) against aflatoxin B1 (AF) toxicity in rabbits. A total of 72 growing rabbits (5-week-old) were distributed into six equal groups (4 replicates with 3 rabbits each). The experimental groups are as follows: control group, AF group (supplemented with AF 0.3 mg/kg diet), AF + Sor group (AF 0.3 mg/kg diet + Sor 2 g/kg diet), AF + Hsc group (AF 0.3 mg/kg diet + Hsc 5 g/kg diet), AF + L-M group (AF 0.3 mg/kg diet + L-M 8 g/kg diet) and AF + Mix group (AF 0.3 mg/kg diet + 2 Sor + 5 Hsc + 8 L-M g/kg diet). Live body weight and weight gain at 13 weeks of age were significantly reduced by AF. Feed intake at 13 weeks of age was decreased in AF, AF + Hsc and AF + Mix compared to the control. AF, AF + Hsc and AF + Mix showed the lowest total antioxidant capacity compared to the control. The highest level of reactive oxygen species and 8-Hydroxy-2-desoxyguanosine was observed in AF group. Using of other supplements with AF increased immunoglobulinM than AF alone. In conclusion, dietary supplementation of Sor, L-M, Hsc or their mixture was effective in reducing the adverse effects of AF on performance, antioxidant and immune status of rabbits with more better improvement obtained by Sor or L-M separately.


Assuntos
Aflatoxina B1/toxicidade , Silicatos de Alumínio/farmacologia , Metionina/farmacologia , Coelhos/crescimento & desenvolvimento , Ácido Sórbico/farmacologia , 8-Hidroxi-2'-Desoxiguanosina/sangue , Silicatos de Alumínio/administração & dosagem , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Dieta/veterinária , Suplementos Nutricionais , Contaminação de Alimentos , Imunoglobulina M/sangue , Malondialdeído/sangue , Metionina/administração & dosagem , Coelhos/sangue , Espécies Reativas de Oxigênio/sangue , Ácido Sórbico/administração & dosagem
2.
Andrologia ; 52(1): e13426, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31670414

RESUMO

There is a current interest from the food packaging, biomedical and agricultural sectors in hybrid materials formed from clays and natural polymeric compounds. However, research investigating the toxicity of vermiculite-cellulose nanocrystal (VERN) hybrid on the testes of Wistar rats is rare. Twenty rats, divided into control and treatment groups, were orally administered distilled water, 5, 10, and 20 mg/kg bw VERN daily for two consecutive weeks. At the termination of experiments, the testicular organo-somatic index, superoxide dismutase, catalase, and gamma-glutamyl transferase activities were not significantly changed by VERN relative to the controls. Contrarily, myeloperoxidase, glutathione peroxidase, and malondialdehyde levels were depleted in the testes of treated rats. Moreso, VERN increased follicle-stimulating and luteinizing hormones, and decreased testosterone levels at the 20 mg/kg dose. Histology of the testes revealed healthy looking Leydig cells at the doses of 5 and 10 mg/kg VERN. Overall, these results indicate that oral exposure of VERN was not overly deleterious to the redox and structural histoarchitecture in the testes of rats.


Assuntos
Silicatos de Alumínio/toxicidade , Celulose/toxicidade , Nanocompostos/toxicidade , Espermatozoides/efeitos dos fármacos , Testículo/efeitos dos fármacos , Administração Oral , Silicatos de Alumínio/administração & dosagem , Animais , Catalase/análise , Catalase/metabolismo , Celulose/administração & dosagem , Hormônio Foliculoestimulante/sangue , Glutationa Peroxidase/análise , Glutationa Peroxidase/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Hormônio Luteinizante/sangue , Masculino , Modelos Animais , Nanocompostos/administração & dosagem , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Wistar , Superóxido Dismutase/análise , Superóxido Dismutase/metabolismo , Testículo/enzimologia , Testosterona/sangue , Testes de Toxicidade Aguda
3.
J Dairy Sci ; 101(12): 11421-11434, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30316598

RESUMO

Mitigation strategies are vital in minimizing the health and economic risks associated with dairy cattle exposure to aflatoxin (AF). The objective of this study was to determine the effects of a commercially available aluminosilicate clay in a lactation diet on production responses, blood chemistry, and liver inflammatory markers of multiparous lactating Holstein cows during an AF challenge. Sixteen multiparous lactating Holstein cows [body weight (mean ± SD) = 758 ± 76 kg; days in milk = 157 ± 43 d] were assigned to 1 of 4 treatments in a replicated 4 × 4 Latin square design with 21-d periods: no adsorbent and no AF challenge (CON), no adsorbent and an AF challenge (POS), 113 g of aluminosilicate clay top-dressed on the total mixed ration (adsorbent; FloMatrix, PMI Nutritional Additives, Arden Hills, MN) with an AF challenge (F4), or 227 g of adsorbent with an AF challenge (F8). The challenge consisted of 100 µg of AFB1/kg of dietary dry matter intake administered orally. For each period, milk was sampled 3× daily from d 14 to 21; blood, feces, and urine were sampled on d 14, 18, and 21; and liver samples were taken on d 18. Liver tissue was assessed for gene expression and histological hepatocyte inflammation. Statistical analysis was preformed using the MIXED and GLIMMIX procedures of SAS (SAS Institute Inc., Cary, NC). Fat-corrected milk (POS = 37.2, F4 = 39.2, and F8 = 38.9 kg/d) increased as concentration of adsorbent in the diet increased. There was a decrease in milk AFM1 concentration at d 18 as concentration of adsorbent in the diet increased (POS = 0.33, F4 = 0.32, and F8 = 0.27 µg/kg). There was a decrease in AFM1 concentration in urine (POS = 2.10, F4 = 1.89, and F8 = 1.78 µg/kg) and AFB1 concentration in feces (POS = 4.68, F4 = 3.44, and F8 = 3.17 µg/kg) as concentration of adsorbent in the diet increased. Cows in CON had greater concentrations of serum cholesterol (202 mg/dL) and plasma superoxide dismutase (2.8 U/mL) compared with cows in POS (196 mg/dL and 2.6 U/mL, respectively). Plasma glutamate dehydrogenase increased as concentration of adsorbent in the diet increased (POS = 37.8, F4 = 39.3, and F8 = 39.1 U/L). The expression of NFKB1 was greater in the liver of cows in POS (0.78) compared with cows in CON (0.70). The expression of MTOR was greater in the liver of cows in CON (1.19) compared with cows in POS (0.96). When compared with cows in CON, cows in POS had greater odds ratio for hepatocyte inflammation (odds ratio = 5.14). In conclusion, the adsorbent used in this study had a positive effect on milk production and hepatocyte inflammation and reduced AF transfer.


Assuntos
Aflatoxinas/toxicidade , Silicatos de Alumínio/administração & dosagem , Doenças dos Bovinos/tratamento farmacológico , Bovinos/fisiologia , Inflamação/veterinária , Animais , Doenças dos Bovinos/etiologia , Doenças dos Bovinos/imunologia , Doenças dos Bovinos/fisiopatologia , Argila/química , Dieta/veterinária , Fezes/química , Feminino , Inflamação/tratamento farmacológico , Inflamação/etiologia , Inflamação/fisiopatologia , Lactação , Fígado/efeitos dos fármacos , Fígado/imunologia , Leite/metabolismo
4.
Food Chem Toxicol ; 114: 316-324, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29496528

RESUMO

Populations consuming aflatoxin (AF) and fumonisin (FN)-contaminated foods may be at increased risk for hepatocellular carcinoma (HCC) and developmental disorders; consequently, development of intervention strategies to reduce AF/FN-induced liver disease and adverse health effects in humans could be very useful. Calcium montmorillonite clay (NovaSil) has been shown to absorb AF in vitro, in multiple animal models, as well as in human studies. In the present study, we aimed to evaluate whether uniform particle size NovaSil (UPSN) possessed an ability to modulate the co-carcinogenic potentials of aflatoxin B1 (AFB1) and fumonisin B1 (FB1) in F344 rats. Sequential treatment of FB1 following AFB1 synergistically induces preneoplastic alterations as well as liver damage, indicating that AFB1 acts as an initiator while FB1 as a promoter in the carcinogenesis model, confirming findings from previous studies. The enterosorbent agent UPSN clay at dose of up to 0.5% in diet was shown to be effective in modulating the toxicity and carcinogenicity of co-exposure to AFB1 and FB1, as demonstrated by significant reduction in number and size of hepatic GST-P+ foci, in alterations indicative of liver toxicity, and in levels of AFB1 and FB1 biomarkers.


Assuntos
Aflatoxina B1/toxicidade , Silicatos de Alumínio/administração & dosagem , Bentonita/administração & dosagem , Fumonisinas/toxicidade , Hepatopatias/tratamento farmacológico , Adsorção , Aflatoxina B1/química , Aflatoxina B1/metabolismo , Silicatos de Alumínio/química , Silicatos de Alumínio/metabolismo , Animais , Bentonita/química , Bentonita/metabolismo , Argila , Fumonisinas/química , Fumonisinas/metabolismo , Humanos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Hepatopatias/etiologia , Hepatopatias/metabolismo , Masculino , Ratos , Ratos Endogâmicos F344
5.
J Dairy Sci ; 101(4): 3008-3020, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29428756

RESUMO

The study was conducted to examine the effect of supplementing bentonite clay with or without a Saccharomyces cerevisiae fermentation product (SCFP; 19 g of NutriTek + 16 g of MetaShield, both from Diamond V, Cedar Rapids, IA) on the performance and health of dairy cows challenged with aflatoxin B1 (AFB1). Twenty-four lactating Holstein cows (64 ± 11 d in milk) were stratified by parity and milk production and randomly assigned to 1 of 4 treatment sequences. The experiment had a balanced 4 × 4 Latin square design with 6 replicate squares, four 33-d periods, and a 5-d washout interval between periods. Cows were fed a total mixed ration containing 36.1% corn silage, 8.3% alfalfa hay, and 55.6% concentrate (dry matter basis). Treatments were (1) control (no additives), (2) toxin (T; 1,725 µg of AFB1/head per day), (3) T + clay (CL; 200 g/head per day; top-dressed), and (4) CL+SCFP (CL+SCFP; 35 g/head per day; top-dressed). Cows were adapted to diets from d 1 to 25 (predosing period) and then orally dosed with AFB1 from d 26 to 30 (dosing period), and AFB1 was withdrawn from d 31 to 33 (withdrawal period). Milk samples were collected twice daily from d 21 to 33, and plasma was sampled on d 25 and 30 before the morning feeding. Transfer of ingested AFB1 into milk aflatoxin M1 (AFM1) was greater in T than in CL or CL+SCFP (1.65 vs. 1.01 and 0.94%, respectively) from d 26 to 30. The CL and CL+SCFP treatments reduced milk AFM1 concentration compared with T (0.45 and 0.40 vs. 0.75 µg/kg, respectively), and, unlike T, both CL and CL+SCFP lowered AFM1 concentrations below the US Food and Drug Administration action level (0.5 µg/kg). Milk yield tended to be greater during the dosing period in cows fed CL+SCFP compared with T (39.7 vs. 37.7 kg/d). Compared with that for T, plasma glutamic oxaloacetic transaminase concentration, indicative of aflatoxicosis and liver damage, was reduced by CL (85.9 vs. 95.2 U/L) and numerically reduced by CL+SCFP (87.9 vs. 95.2 U/L). Dietary CL and CL+SCFP reduced transfer of dietary AFB1 to milk and milk AFM1 concentration. Only CL prevented the increase in glutamic oxaloacetic transaminase concentration, and only CL+SCFP prevented the decrease in milk yield caused by AFB1 ingestion.


Assuntos
Aflatoxina B1/farmacologia , Silicatos de Alumínio/metabolismo , Bentonita/metabolismo , Bovinos/metabolismo , Leite/química , Saccharomyces cerevisiae/química , Silicatos de Alumínio/administração & dosagem , Ração Animal/análise , Animais , Bentonita/administração & dosagem , Bovinos/imunologia , Argila , Dieta/veterinária , Suplementos Nutricionais/análise , Feminino , Fermentação , Nível de Saúde , Lactação , Distribuição Aleatória
6.
Environ Toxicol ; 33(6): 623-630, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29457689

RESUMO

Halloysite (Al2 Si2 O5 (OH)4 ·nH2 O) nanotubes (HNTs) are natural clay materials and widely applied in many fields due to their natural hollow tubular structures. Many in vitro studies indicate that HNTs exhibit a high level of biocompatibility, however the in vivo toxicity of HNTs remains unclear. The objective of this study was to assess the hepatic toxicity of the purified HNTs in mice via oral route. The purified HNTs were orally administered to mice at 5, 50, and 300 mg/kg body weight (BW) every day for 30 days. Oral administration of HNTs stimulated the growth of the mice at the low dose (5 mg/kg BW) with no liver toxicity, but inhibited the growth of the mice at the middle (50 mg/kg BW) and high (300 mg/kg BW) doses. In addition, oral administration of HNTs at the high dose caused Al accumulation in the liver but had no marked effect on the Si content in the organ. The Al accumulation caused significant oxidative stress in the liver, which induced hepatic dysfunction and histopathologic changes. These findings demonstrated that Al accumulation-induced oxidative stress played an important role in the oral HNTs-caused liver injury.


Assuntos
Silicatos de Alumínio/toxicidade , Alumínio/farmacocinética , Fígado/efeitos dos fármacos , Nanotubos/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Administração Oral , Silicatos de Alumínio/administração & dosagem , Silicatos de Alumínio/química , Silicatos de Alumínio/farmacocinética , Animais , Argila , Dano ao DNA/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos , Nanotubos/química , Fatores de Tempo , Testes de Toxicidade Crônica
7.
Fish Shellfish Immunol ; 75: 27-31, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29409931

RESUMO

The effect of Sodium Bentonite (SB) enriched diet on growth performance, innate immune response, and disease resistance in stinging catfish, Heteropneustes fossilis against Aeromonas hydrophila is reported. The infected fish fed with 5% SB had the maximum weight gain diet (PWG %) and specific growth rate (SGR %) were 26% and 29% when compared to 14% and 17% with 10% diet. Similarly the phagocytic activity increased significantly when infected fish were fed with 5% or 10% SB diets during the experimental period; the complement, respiratory burst and lysozyme activities were also significantly enhanced on weeks 2 and 4. The lower cumulative mortality (10% and 15%) was observed when the infected fish were fed with 5% and 10% SB diets for 30 days. The results suggest that the infected H. fossilis after administration of 5% and 10% SB enriched diets for 30 days had significantly improved growth performance, innate immunity, and disease resistance against A. hydrophilla. Hence, sodium bentonite can be used as a feed additive to stimulate immunity and for disease resistance in the effective production of economically valuable freshwater catfish, H. fossilis.


Assuntos
Silicatos de Alumínio/metabolismo , Bentonita/metabolismo , Peixes-Gato/crescimento & desenvolvimento , Peixes-Gato/imunologia , Resistência à Doença/imunologia , Doenças dos Peixes/imunologia , Imunidade Inata/efeitos dos fármacos , Aeromonas hydrophila/fisiologia , Silicatos de Alumínio/administração & dosagem , Ração Animal/análise , Animais , Bentonita/administração & dosagem , Peixes-Gato/metabolismo , Argila , Dieta/veterinária , Suplementos Nutricionais/análise , Resistência à Doença/efeitos dos fármacos , Infecções por Bactérias Gram-Negativas/imunologia
8.
Graefes Arch Clin Exp Ophthalmol ; 256(3): 535-546, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29353344

RESUMO

PURPOSE: To study the safety and biocompatibility of Laponite clay (LAP) within an intravitreal and suprachoroidal administration in rabbit eyes. METHODS: Thirty-two New Zealand albino rabbits were divided into two experimental groups to test intravitreal (IVT group) and suprachoroidal (SCS group) administration of a 100-µl and 50-µl Laponite suspension respectively. Following injection, the eyes were monitored by ocular tonometry, slit-lamp eye examination and indirect ophthalmoscopy, at 24 h, 1, 4, 12, and 14 weeks post administration. Histological examination was also performed to determine whether any ocular pathological change had occurred. Throughout the study, LAP presence in vitreous was estimated by complexometric titration with ethylenediaminetetraacetic acid (EDTA), taking advantage of the Laponite high content of magnesium ions. RESULTS: Neither significant differences in the intraocular pressure, nor relevant ocular complications were found in the two experimental groups after LAP administration. The histology of the retina remained unchanged. LAP presence in vitreous could be indirectly confirmed by complexometric titration until 14 weeks post administration in eyes of IVT group. CONCLUSION: Laponite could be considered as a vehicle for potential clinical use in ocular drug administration, due to its proven ocular biocompatibility and its transparency in gel state.


Assuntos
Retina/patologia , Doenças Retinianas/tratamento farmacológico , Silicatos/administração & dosagem , Visão Ocular , Silicatos de Alumínio/administração & dosagem , Animais , Materiais Biocompatíveis/administração & dosagem , Argila , Modelos Animais de Doenças , Eletrorretinografia , Feminino , Injeções Intravítreas , Oftalmoscopia , Coelhos , Retina/efeitos dos fármacos , Retina/fisiopatologia , Doenças Retinianas/diagnóstico , Doenças Retinianas/fisiopatologia
9.
Artigo em Inglês | MEDLINE | ID: mdl-29210610

RESUMO

A presence of mycotoxins in feed is one of the most alarming issues in the poultry feed industry. Ochratoxins, produced by several Aspergillus and Penicillium species, are important mycotoxin regarding the health status of poultry birds. Ochratoxins are further classified into to several subtypes (A, B, C, etc) depending on their chemical structures, but ochratoxin A (OTA) is considered the most important and toxic. Bentonite clay, belonging to phyllosilicates and formed from weathering of volcanic ashes, has adsorbent ability for several mycotoxins. The present study was designed to study the effects of bentonite clay upon OTA-induced immunosuppression in broiler chicks. For this, 480 day-old broiler chicks were procured from a local hatchery and then different combinations of OTA (0.15, 0.3, or 1.0 mg/kg) and bentonite clay (5, 10, and 20 g/kg) were incorporated into their feed. At 13, 30, and 42 days of age, parameters such as antibody responses to sheep red blood cells, in situ lymphoproliferative responses to mitogen (PHA-P), and in situ phagocytic activity (i.e., via carbon clearance) were determined respectively. The results indicated there was a significant reduction of total antibody and immunoglobulin titres, lymphoproliferative responses, and phagocytic potential in OTA-treated birds, suggesting clear immunosuppression by OTA in birds in a dose-dependent manner. These results were also significantly lower in all combination groups (OTA with bentonite clay), suggesting few to no effects of feeding bentonite clay upon OTA- induced alterations in different immune parameters.


Assuntos
Silicatos de Alumínio/análise , Ração Animal/análise , Bentonita/análise , Análise de Alimentos , Contaminação de Alimentos/análise , Imunossupressão , Ocratoxinas/análise , Silicatos de Alumínio/administração & dosagem , Animais , Anticorpos/imunologia , Bentonita/administração & dosagem , Galinhas , Argila , Imunoglobulinas/imunologia , Ocratoxinas/administração & dosagem , Ocratoxinas/farmacologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia
10.
J Anim Sci ; 95(10): 4658-4667, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29108043

RESUMO

Three experiments were conducted to determine the effect of increasing concentrations of a smectite clay on toxin binding capacity, ruminal fermentation, diet digestibility, and growth of feedlot cattle. In Exp. 1, 72 Angus × Simmental steers were blocked by BW (395 ± 9.9 kg) and randomly allotted to 3 treatments (4 pens/treatment and 6 steers/pen) to determine the effects of increasing amounts of clay (0, 1, or 2%) on performance. The clay was top-dressed on an 80% concentrate diet at a rate of 0, 113, or 226 g/steer daily to achieve the 0, 1, and 2% treatments, respectively. Steers were slaughtered at a target BW of 606 kg. In Exp. 2, 6 steers (596 ± 22.2 kg initial BW) were randomly allotted to the same 3 treatments in a replicated 3 × 3 Latin square design (21-d periods) to determine the effects of increasing amounts of clay on ruminal pH, VFA, and nutrient digestibility. In Exp. 3, 150 mg of clay was incubated in 10 mL of rumen fluid with 3 incremental concentrations (6 replicates per concentration) of aflatoxin B (AFB) or ergotamine tartate (ET) to determine binding capacity. During the first 33-d period, there was a quadratic effect of clay on ADG ( < 0.01) and G:F ( < 0.01), increasing from 0 to 1% clay and then decreasing from 1 to 2% clay. However, during the second 30-d period, clay linearly decreased ADG and G:F ( ≤ 0.03) and overall ADG, DMI, and G:F were not impacted ( ≥ 0.46). Clay linearly decreased marbling score ( = 0.05). Hepatic enzyme activity did not differ among treatments on d 0 or at slaughter ( ≥ 0.15). Clay linearly decreased ruminal lactate and propionate, linearly increased formate and the acetate:propionate ratio ( ≤ 0.04), and tended ( = 0.07) to linearly increase butyrate. Clay tended to linearly increase ( = 0.06) OM and CP apparent digestibility. Ruminal pH, urine pH, and other digestibility measures did not differ among treatments ( ≥ 0.15). Clay was able to effectively bind AFB and ET at concentrations above the normal physiological range (52 and 520 µg/mL), but proportional adsorption was decreased to 35.5 and 91.1% at 5,200 µg/mL ( < 0.01) for AFB and ET, respectively. In conclusion, clay effectively binds ruminal toxins, decreases ruminal lactate, and improves performance only during adaptation to a high-concentrate feedlot diet.


Assuntos
Silicatos de Alumínio/administração & dosagem , Ração Animal/análise , Bovinos/fisiologia , Suplementos Nutricionais , Animais , Nitrogênio da Ureia Sanguínea , Bovinos/crescimento & desenvolvimento , Argila , Dieta/veterinária , Digestão , Fermentação , Testes de Função Hepática/veterinária , Masculino , Rúmen/metabolismo
11.
J Dairy Sci ; 99(10): 8028-8040, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27522430

RESUMO

Oral supplementation of clay has been reported to function as buffer in dairy cows. However, its effects on rumen, blood, and fecal pH have varied among studies. Our objective was to determine the effects of 3 concentrations of dietary clay supplementation after a grain challenge. Ten multiparous rumen-cannulated Holstein cows [body weight (mean ± standard deviation)=648±12kg] with 142±130 (60 to 502) days in milk were assigned to 1 of 5 treatments in a replicated 5×5 Latin square design balanced to measure carryover effects. Periods (21d) were divided into an adaptation phase (d 1 to 18, with regular total mixed ration fed ad libitum) and a measurement phase (d 19 to 21). Feed was restricted on d 18 to 75% of the average of the total mixed ration fed from d 15 to 17 (dry matter basis), and on d 19 cows received a grain challenge. The challenge consisted of 20% finely ground wheat administered into the rumen via a rumen cannula, based on the average dry matter intake obtained on d 15 to 17. Treatments were POS (no clay plus a grain challenge), 3different concentrations of clay (0.5, 1, or 2% of dietary dry matter intake), and control (C; no clay and no grain challenge). Statistical analysis was performed using the MIXED procedure of SAS (SAS Institute Inc., Cary, NC). Contrasts 1 (POS vs. C) and 2 (POS vs. the average of 0.5, 1, or 2%) were compared, along with linear and quadratic treatment effects. Rumen, fecal, and blood pH, along with blood metabolites, were measured at 0, 4, 8, 12, 16, 20, 24, 36, and 48h relative to the grain challenge. Cows fed POS had lower rumen pH [(mean ± standard error) 6.03±0.06] than cows fed C (6.20±0.06). Cow fed POS had lower fecal pH (6.14±0.04) than cows fed C (6.38±0.04). We observed a linear treatment effect for rumen pH and fecal pH. Fecal pH (6.22±0.04) was higher for cows fed clay (contrast 2) then for cows fed POS (6.14±0.04). We also observed a treatment difference (contrast 2) for negative incremental area under the curve, pH below 5.6 × h/d, (0.5% clay=7.93±0.83, 1% clay=8.56±0.83, and 2% clay=7.79±0.83) compared with POS (11.0±0.83). Cows fed clay tended to have higher milk yield (0.5% clay=28.8±3.4kg, 1% clay=30.2±3.4kg, and 2% clay=29.1±3.4kg, contrast 2), and had higher 3.5% fat-corrected milk (0.5% clay=29.9±3.5kg, 1% clay=34.1±3.5kg, and 2% clay=33.1±3.4kg), and higher energy-corrected milk (0.5% clay=29.1±3.3kg, 1% clay=32.8±3.4kg, and 2% clay=31.6±3.3kg) than cows fed POS (27.7±3.4kg, 28.0±3.4kg, 27.7±3.3kg, respectively). In conclusion, cows fed clay had higher rumen pH, energy-corrected milk, fat-corrected milk, and a trend for milk yield than cows fed POS.


Assuntos
Silicatos de Alumínio/administração & dosagem , Grão Comestível , Fezes/química , Leite/química , Rúmen/metabolismo , Ração Animal/análise , Animais , Bovinos , Argila , Dieta/veterinária , Suplementos Nutricionais , Feminino , Concentração de Íons de Hidrogênio , Lactação
12.
Appetite ; 105: 557-61, 2016 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-27364379

RESUMO

BACKGROUND AND INTRODUCTION: Previous studies of soil eating, or geophagia, among pregnant women in sub-Saharan Africa indicate the practice is widespread. Various explanations have been explored to explain the global phenomenon of soil eating, with the most compelling explanation focused on clay's ability to prevent or treat intestinal infection. The urban South African context for clay eating is not well understood. This paper explores clay consumption amongst pregnant migrants who are nationals of countries where clay consumption may be common. METHODS: I conducted in-depth interviews with a purposively selected group of Somali, Congolese, and Zimbabwean women (n = 23). Interviews included questions broadly related to maternal and infant nutrition. In addition, I conducted nine focus group discussions (n = 48) with adult Somali, Congolese (DRC), and Zimbabwean men (N = 3) and women (N = 6), segregated by country of origin and gender. This paper focuses specifically on responses related to geophagia. RESULTS: While Somali women did not report consuming clay or charcoal, Congolese and Zimbabwean participants self-reported commonly consuming clay during pregnancy, and at times also when not pregnant. Despite having heard public health messaging that discouraged the practice, participants largely did not describe this consumption in terms of health, but rather in terms of craving and habit. Participants described continued consumption of clay in South Africa, and the only reason for ceasing consumption was in cases of severe constipation. DISCUSSION: The widespread consumption of clay soil by Congolese and Zimbabwean women during pregnancy may be a mechanism through which identity was reasserted and reproduced in a foreign country. Participants' emphasis on clay consumption seemed related to the absence or expense of other craved foods, and perhaps also to feelings of loss in Cape Town.


Assuntos
Emigrantes e Imigrantes/psicologia , Hábitos , Pica/psicologia , Migrantes , Silicatos de Alumínio/administração & dosagem , Argila , Fissura , República Democrática do Congo , Dieta/psicologia , Feminino , Grupos Focais , Humanos , Masculino , Gravidez/psicologia , Saúde Pública , Solo , Somália , África do Sul , Zimbábue
13.
Carbohydr Polym ; 151: 130-134, 2016 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-27474551

RESUMO

Quaternized carboxymethyl chitosan/organic rectorite (QCMC/OREC) nanocomposites were rapidly prepared by intercalating QCMC into the layer of OREC under microwave irradiation. And then copper-chelate QCMC/OREC (QCMC/OREC-Cu) nanocomposites were obtained by mixing QCMC/OREC with CuSO4 solution. XRD and TEM results indicated that QCMC/OREC nanocomposites were obtained and QCMC was dispersed in the interlayer of OREC. Besides, FT-IR results revealed that the hydrogen bonds and electrostatic interaction in QCMC/OREC-Cu were both stronger than those in QCMC/OREC because of introducing the Cu(2+). The thermogravimetric analysis showed that the thermal stability of QCMC/OREC-Cu nanocomposites was higher than QCMC and QCMC/OREC. Algae inhibition assay revealed that QCMC/OREC-Cu nanocomposites had stronger antifouling activity than original QCMC and QCMC/OREC. This work provides important basis for developing novel antifouling materials.


Assuntos
Silicatos de Alumínio , Quitosana/análogos & derivados , Cobre , Desinfetantes , Minerais , Nanocompostos , Silicatos de Alumínio/administração & dosagem , Silicatos de Alumínio/química , Quitosana/administração & dosagem , Quitosana/química , Clorofila/metabolismo , Clorofila A , Cobre/administração & dosagem , Cobre/química , Diatomáceas/efeitos dos fármacos , Diatomáceas/crescimento & desenvolvimento , Diatomáceas/metabolismo , Desinfetantes/administração & dosagem , Desinfetantes/química , Minerais/administração & dosagem , Minerais/química , Nanocompostos/administração & dosagem , Nanocompostos/química
14.
J Immunotoxicol ; 13(5): 628-37, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27294391

RESUMO

High contamination by aflatoxin B1 (AFB1) has been detected in Beja province (Tunisia) in many dairy products and animal feed, which has resulted in many tons of cereals and cereals being removed from the market, causing economic loss. While removal represents a means of reducing risk, exposures still occur. Studies have increasingly focused on means of AFB1 biodegradation/elimination using lactic acid bacteria and clay mineral. In the study here, Lactobacillus paracasei BEJ01 (LP) and montmorilonite clay (MT) were used to reduce the physio-/immunotoxicologic disorders that could develop in rats that underwent AFB1 exposures for a total of 7 consecutive days. The results indicated that rats treated with AFB1 (80 µg/kg BW) alone had significant decreases in lymphocytes in their blood (including B-lymphocytes, CD3(+), CD4(+), and CD8(+) T-lymphocyte subtypes, and NK cells), immunoglobulins (IgA and IgG) and pro-inflammatory cytokines; these rats also had altered oxidative stress status. In contrast, in rats treated with LP + MT (2 × 10(9) cfu/ml [∼ 2 mg/kg] + 0.5 mg MT/kg BW) for a total of 7 days before, concurrent with or after AFB1 treatment, there was a significant blockade/mitigation of each AFB1-impacted parameter. Moreover, treatment with the mixture at any point in relation to AFB1 treatment expectedly caused enhanced TNFα and IL-1ß expression relative to control values; all other parameters were comparable to values noted in control rats. Alone, the mixture had no impact on host parameters. From the results here it may be concluded the the LP + MT mixture was effective in protecting these hosts against AFB1-induced immunologic/physiologic disorders and that LP + MT could prevent and/or mitigate AFB1 toxicities in vivo.


Assuntos
Aflatoxina B1/metabolismo , Biodegradação Ambiental , Contaminação de Alimentos/prevenção & controle , Doenças Transmitidas por Alimentos/prevenção & controle , Lactobacillus paracasei/imunologia , Aflatoxina B1/toxicidade , Silicatos de Alumínio/administração & dosagem , Animais , Formação de Anticorpos , Bentonita/administração & dosagem , Argila , Doenças Transmitidas por Alimentos/imunologia , Humanos , Interleucina-1beta/metabolismo , Linfopenia , Masculino , Estresse Oxidativo , Ratos , Fator de Necrose Tumoral alfa/metabolismo , Tunísia
15.
Artigo em Inglês | MEDLINE | ID: mdl-27321368

RESUMO

South Texas currently has the highest incidence of hepatocellular carcinoma (HCC) in the United States, a disease that disproportionately affects Latino populations in the region. Aflatoxin B1 (AFB1) is a potent liver carcinogen that has been shown to be present in a variety of foods in the United States, including corn and corn products. Importantly, it is a dietary risk factor contributing to a higher incidence of HCC in populations frequently consuming AFB1-contaminated diets. In a randomised double-blind placebo controlled trial, we evaluated the effects of a 3-month administration of ACCS100 (refined calcium montmorillonite clay) on serum AFB1-lysine adduct (AFB-Lys) level and serum biochemistry in 234 healthy men and women residing in Bexar and Medina counties, Texas. Participants recruited from 2012 to 2014 received either a placebo, 1.5 g or 3 g ACCS100 each day for 3 months, and no treatment during the fourth month. Adverse event rates were similar across treatment groups and no significant differences were observed for serum biochemistry and haematology parameters. Differences in levels of AFB-Lys at 1, 3 and 4 months were compared between placebo and active treatment groups. Although serum AFB-Lys levels were decreased by month 3 for both treatment groups, the low dose was the only treatment that was significant (p = 0.0005). In conclusion, the observed effect in the low-dose treatment group suggests that the use of ACCS100 may be a viable strategy to reduce dietary AFB1 bioavailability during aflatoxin outbreaks and potentially in populations chronically exposed to this carcinogen.


Assuntos
Aflatoxina B1/sangue , Silicatos de Alumínio/uso terapêutico , Bentonita/uso terapêutico , Cálcio/uso terapêutico , Venenos/sangue , Adulto , Aflatoxina B1/administração & dosagem , Silicatos de Alumínio/administração & dosagem , Bentonita/administração & dosagem , Bentonita/efeitos adversos , Biomarcadores , Cálcio/administração & dosagem , Argila , Método Duplo-Cego , Feminino , Humanos , Masculino , Venenos/administração & dosagem , Texas
16.
J Appl Microbiol ; 121(1): 136-48, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27138244

RESUMO

AIMS: To investigate the mechanisms leading to an increase in the prevalence of blaCMY -2 conferring resistance to ceftiofur in pigs receiving a feed medicated with chlortetracycline and penicillin, and to examine the effect of supplementation with a clay mineral on this phenomenon. METHODS AND RESULTS: In 138 blaCMY -2 -positive Escherichia coli isolates from faeces of pigs receiving feed supplemented or not with 2% clinoptilolite, from day 2 to day 28 after weaning, isolates from the two groups differed significantly with respect to their phylogenetic group: phylotype A predominated in the supplemented group, whereas phylotypes B1 and D predominated in the control group, as determined by PCR. In 36 representative isolates, pulsed-field gel electrophoresis and antimicrobial susceptibility testing revealed that the blaCMY -2 -positive E. coli isolates were polyclonal with diverse antimicrobial resistance patterns and blaCMY -2 -carrying plasmids of incompatibility (Inc) groups, A/C, I1 and ColE were observed in transformants as detected by PCR. Enterobacter cloacae possessing blaCMY -2 -carrying IncA/C plasmids were found in the pens before introduction of this batch of pigs. The blaCMY -2 -positive E. coli isolates were more clonally diverse in the control group than the supplemented group. CONCLUSIONS: The blaCMY -2 gene appears to have spread both horizontally and clonally in this batch of pigs and may have spread from previous batches of pigs via plasmids carried by Ent. cloacae and expanded in animals of the present batch in the presence of the selection pressure due to administration of chlortetracycline and penicillin in the feed. Feed supplementation may have an effect on clonal diversity of blaCMY -2 -positive isolates. SIGNIFICANCE AND IMPACT OF THE STUDY: Implementation of improved hygiene measures, decreased administration of certain antimicrobials on farm and feed supplementation with certain ingredients may limit antimicrobial resistance spread between and within batches of animals.


Assuntos
Silicatos de Alumínio/administração & dosagem , Suplementos Nutricionais/análise , Infecções por Escherichia coli/veterinária , Escherichia coli/enzimologia , Doenças dos Suínos/microbiologia , beta-Lactamases/metabolismo , Silicatos de Alumínio/química , Ração Animal/análise , Animais , Antibacterianos/farmacologia , Cefalosporinas/farmacologia , Clortetraciclina/farmacologia , Argila , Farmacorresistência Bacteriana , Eletroforese em Gel de Campo Pulsado , Escherichia coli/classificação , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/fisiopatologia , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Fazendas , Fezes/microbiologia , Filogenia , Plasmídeos/genética , Plasmídeos/metabolismo , Suínos , Doenças dos Suínos/fisiopatologia , Desmame , beta-Lactamases/genética
17.
Appetite ; 105: 85-94, 2016 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-27191407

RESUMO

Three experiments were conducted showing rats' pica behavior (kaolin clay intake) due to running in activity wheels. The amount of kaolin consumed was a positive function of the available time of voluntary running (20, 40, or 60 min), although this relationship was blunted by a descending (i.e., 60 â†’ 40 â†’ 20 min) test series of execution (Experiment 1). Pica was also generated by forced running in a motorized wheel for 60 min as a positive function of the speed of wheel rotations at 98, 185, or 365 m/h, independent of the order of execution (Experiment 2). Voluntary running generated more pica than did forced running at 80 m/h, although the distance travelled in the former condition was 27% lesser than that in the latter condition (Experiment 3). Because kaolin intake is regarded as a reliable measure of nausea in rats, these results show that wheel running, either voluntary or forced, induces nausea in rats.


Assuntos
Modelos Animais de Doenças , Comportamento Alimentar , Caulim/administração & dosagem , Atividade Motora , Náusea/etiologia , Esforço Físico , Pica/fisiopatologia , Silicatos de Alumínio/administração & dosagem , Animais , Comportamento Animal , Argila , Ingestão de Energia , Masculino , Náusea/prevenção & controle , Ratos Wistar , Reprodutibilidade dos Testes , Fatores de Tempo
18.
Sci Rep ; 5: 17515, 2015 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-26631982

RESUMO

Mica, an aluminosilicate mineral, has been proven to possess anti-tumor and immunostimulatory effects. However, its efficacy and mechanisms in treating various types of tumor are less verified and the mechanistic link between anti-tumor and immunostimulatory effects has not been elucidated. We sought to investigate the therapeutic effect of STB-HO (mica nanoparticles) against one of the most prevalent cancers, the breast cancer. STB-HO was orally administered into MCF-7 xenograft model or directly added to culture media and tumor growth was monitored. STB-HO administration exhibited significant suppressive effects on the growth of MCF-7 cells in vivo, whereas STB-HO did not affect the proliferation and apoptosis of MCF-7 cells in vitro. To address this discrepancy between in vivo and in vitro results, we investigated the effects of STB-HO treatment on the interaction of MCF-7 cells with macrophages, dendritic cells (DCs) and natural killer (NK) cells, which constitute the cellular composition of tumor microenvironment. Importantly, STB-HO not only increased the susceptibility of MCF-7 cells to immune cells, but also stimulated the immunocytes to eliminate cancer cells. In conclusion, our study highlights the possible role of STB-HO in the suppression of MCF-7 cell growth via the regulation of interactions between tumor cells and anti-tumor immune cells.


Assuntos
Silicatos de Alumínio/farmacologia , Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Microambiente Tumoral/imunologia , Silicatos de Alumínio/administração & dosagem , Silicatos de Alumínio/química , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Neoplasias da Mama/imunologia , Neoplasias da Mama/patologia , Proliferação de Células/efeitos dos fármacos , Células Dendríticas/efeitos dos fármacos , Feminino , Humanos , Células Matadoras Naturais/efeitos dos fármacos , Células Matadoras Naturais/imunologia , Células MCF-7/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Camundongos Nus , Nanopartículas/química , Microambiente Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
19.
Int J Pharm ; 495(2): 816-26, 2015 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-26387616

RESUMO

Gamma-aminobutyric acid (GABA) is a key neurotransmitter where it usually inhibits impulse transmission. GABA release blockage or postsynaptic reaction were determined to provoke epileptic convulsions. The aim of the present study was the development of brain-targeted, nanosized, nontoxic, biocompatible, highly specific formulations. Incorporation of GABA into halloysite nanotubes (HNT) was performed using different methods. Particle size, zeta potential and pH measurements, morphological, thermal, XRD, FTIR analyses and GABA quantification by validated HPLC method were used for the characterization of the systems prepared. Release pattern of GABA from the nanotubes was determined using a dialysis membrane. Following successful incorporation of GABA into HNTs for brain delivery, nanotube formulation coded HNT-GABA H1 was selected for in vivo studies. Smaller particle size with narrow size distribution, possible HNT-GABA interaction indicated by thermal, XRD and FTIR analyses and prolonged release were the parameters considered in this selection. Moreover, HNT-GABA H1 remained stable for 3-month storage period and showed higher cell viability values than GABA. Rats were used in in vivo studies and potential of anticonvulsant effect of GABA was determined in the pentylenetetrazole model of seizure. HNT-GABA H1 was found to increase latency of seizure, decrease ending time of the convulsion, duration of severe convulsion and mortality rate significantly compared to pure GABA. After administration of HNT-GABA H1, GABA concentration in Stratum corsatum measured by enzyme immune assay showed that it was not significantly higher than GABA administered alone. These findings suggest that GABA loaded HNTs reduces the duration of all phases of convulsion indicating efficient delivery of GABA to all brain areas to interfere with epileptic mechanism.


Assuntos
Silicatos de Alumínio/administração & dosagem , Encéfalo/metabolismo , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/química , Nanotubos/química , Ácido gama-Aminobutírico/administração & dosagem , Ácido gama-Aminobutírico/farmacocinética , Silicatos de Alumínio/química , Animais , Encéfalo/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Argila , Liberação Controlada de Fármacos , Estabilidade de Medicamentos , Masculino , Tamanho da Partícula , Pentilenotetrazol , Ratos , Convulsões/induzido quimicamente , Convulsões/tratamento farmacológico , Esterilização , Ácido gama-Aminobutírico/farmacologia , Ácido gama-Aminobutírico/uso terapêutico
20.
J Endod ; 41(10): 1626-30, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26307509

RESUMO

INTRODUCTION: Quick-Set (Primus Consulting, Bradenton, FL) is a calcium aluminosilicate cement that is a potential alternative to mineral trioxide aggregate (MTA) with greater acid resistance and faster setting. The purpose of this study was to compare the effects of Quick-Set and MTA on pulpal tissues in response to pulpotomy procedures. METHODS: The pulp chambers of 42 maxillary teeth in 7 beagle dogs were accessed, and the coronal pulpal tissue was removed. Pulpotomy procedures were performed, placing the experimental materials directly over the radicular pulp tissues. The dogs were sacrificed at 70 days, and the teeth and surrounding tissues were removed and prepared for histologic analysis. The sections of the pulpotomy areas were scored for inflammation, pulp tissue organization, reactionary dentin formation, and quality of dentinogenesis. RESULTS: The Quick-Set group exhibited significantly more pulpal inflammation (P = .002) and significantly less pulp tissue organization (P = .004). No significant difference was noted for reactionary dentin formation (P = .526) and quality of dentinogenesis (P = .436). CONCLUSIONS: Compared with ProRoot White MTA (Dentsply Tulsa Dental Specialties, Tulsa, OK), Quick-Set exhibited more pulpal inflammation and decreased pulp tissue organization. No significant differences were noted for reactionary dentin formation and quality of dentinogenesis.


Assuntos
Compostos de Alumínio/administração & dosagem , Silicatos de Alumínio/administração & dosagem , Compostos de Cálcio/administração & dosagem , Polpa Dentária/patologia , Óxidos/administração & dosagem , Pulpotomia/métodos , Silicatos/administração & dosagem , Animais , Cimentos Dentários , Cães , Combinação de Medicamentos , Pulpite/patologia
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