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1.
Trials ; 20(1): 623, 2019 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-31703750

RESUMEN

BACKGROUND: This study aims to evaluate the feasibility and efficacy of a complex health intervention, based on the combination of conventional Western medicine and traditional Chinese medicine (TCM), in an outpatient department of a university hospital for patients with frequent episodic or chronic tension-type headaches. METHODS/DESIGN: This is a prospective randomized controlled pilot study with four balanced treatment arms (usual care, acupuncture, training, and training plus acupuncture). Each arm will have 24 patients. After the initial screening examination and randomization, a 6-week treatment period follows, with treatment frequencies decreasing at 2-week intervals. After completion of the intervention, two follow-up evaluations will be performed 3 and 6 months after the start of treatment. At predefined times, the various outcomes (pain intensity, health-related quality of life, pain duration, autonomic regulation, and heart rate variability) as well as the participants' acceptance of the complex treatment will be evaluated with valid assessment instruments (Migraine Disability Assessment, PHQ-D, GAD-7, and SF-12) and a headache diary. The acupuncture treatment will be based on the rules of TCM, comprising a standardized combination of acupuncture points and additional points selected according to individual pain localization. The training therapy comprises a combination of strength training, endurance training, and training to improve flexibility and coordination. Besides descriptive analyses of the samples, their comparability will be assessed using an analysis of variance (ANOVA) or chi-squared tests. Analyses will be performed on an intention-to-treat basis. Potential interaction effects will be calculated using a repeated-measures ANOVA to test the primary and secondary hypotheses. In supplementary analyses, the proportion of treatment responders (those with a 50% reduction in the frequency of pain episodes) will be determined for each treatment arm. DISCUSSION: This trial may provide evidence for the additive effects of acupuncture and medical training therapy as a combination treatment and may scientifically support the implementation of this complex health intervention. TRIAL REGISTRATION: Registered on 11 Feburary 2019. German Clinical Trials Register, DRKS00016723.


Asunto(s)
Terapia por Acupuntura , Entrenamiento Aeróbico , Ensayos Clínicos Controlados Aleatorios como Asunto , Entrenamiento de Fuerza , Cefalea de Tipo Tensional/terapia , Terapia por Acupuntura/efectos adversos , Adulto , Terapia Combinada , Humanos , Medicina Tradicional China , Evaluación de Resultado en la Atención de Salud , Proyectos Piloto , Estudios Prospectivos , Calidad de Vida , Cefalea de Tipo Tensional/psicología
2.
Eur J Pharm Biopharm ; 126: 115-122, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-28870756

RESUMEN

Due to the limited chemical stability of the natural hyperforin molecule, a more stable form of hyperforin, i.e., the hyperforin dicyclohexylammonium salt (HYP-DCHA) has been used for ex vivo and in vitro experiments in recent years, but its actual stability under typical cell culture conditions has never been studied before. In this contribution the stability of HYP-DCHA was examined under typical cell culture conditions. Different cell culture media with and without fetal calf serum (FCS) supplementation were studied with regard to further stabilization of HYP-DCHA determined with HPLC analysis. Furthermore, albumin nanoparticles were examined as a stabilizing carrier system for HYP-DCHA. In this context, the interaction between HYP-DCHA and albumin nanoparticles (ANP) was examined with regard to size and loading with HYP . The effects of HYP-DCHA either supplied in cell culture medium or loaded on ANP on viability and cytotoxicity were studied in vitro on HaCaT monolayers (human keratinocyte cell line). HYP-DCHA supplied in FCS-containing medium was recovered completely after 24h of incubation. However, a lack of FCS caused a total loss of HYP-DCHA after less than 24h incubation time. Supplying HYP-DCHA loaded on ANP in an FCS-free medium resulted in a recovery of about 60% after 24h incubation. HYP-DCHA supplied in medium along with FCS showed a slow dose-dependent decrease in viability of HaCaT cells without any cytotoxic effects (antiproliferative effect). Treatment with HYP-DCHA with a lack of FCS resulted in a significantly faster decrease in viability which was mainly due to cytotoxicity. The latter was true for HYP-DHCA-loaded ANP where increased cytotoxicity was observed despite the presence of FCS. The results show that the stability of the widely used HYP-DCHA is rather limited under cell culture conditions. Especially a lack of FCS leads to degradation and/or oxidation of HYP-DCHA probably causing an increased cytotoxicity. In contrast, FCS supplementation fairly stabilizes HYP-DCHA under cell culture conditions while albumin nanoparticles may serve the same stabilization purpose despite increasing cytotoxic effects onto the cells themselves.


Asunto(s)
Queratinocitos/efectos de los fármacos , Nanopartículas/química , Albúmina Sérica Bovina/química , Albúmina Sérica Bovina/farmacología , Terpenos/química , Terpenos/farmacología , Técnicas de Cultivo de Célula/métodos , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/fisiología , Células Cultivadas , Relación Dosis-Respuesta a Droga , Estabilidad de Medicamentos , Humanos , Queratinocitos/fisiología , Nanopartículas/administración & dosificación , Espectrometría de Masa por Ionización de Electrospray/métodos
3.
J Anim Sci ; 95(9): 3984-3995, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28992014

RESUMEN

The objective was to determine the energy concentration of a diverse array of dietary fat sources and, from these data, develop regression equations that explain differences based on chemical composition. A total of 120 Genetiporc 6.0 × Genetiporc F25 (PIC, Inc., Hendersonville, TN) individually housed barrows were studied for 56 d. These barrows (initial BW of 9.9 ± 0.6 kg) were randomly allotted to 1 of 15 dietary treatments. Each experimental diet included 95% of a corn-soybean meal basal diet plus 5% either corn starch or 1 of 14 dietary fat sources. The 14 dietary fat sources (animal-vegetable blend, canola oil, choice white grease source A, choice white grease source B, coconut oil, corn oil source A, corn oil source B, fish oil, flaxseed oil, palm oil, poultry fat, soybean oil source A, soybean oil source B, and tallow) were selected to provide a diverse and robust range of unsaturated fatty acid:SFA ratios (U:S). Pigs were limit-fed experimental diets from d 0 to 10 and from d 46 to 56, providing a 7-d adaption for fecal collection on d 7 to 10 (13 kg BW) and d 53 to 56 (50 kg BW). At 13 kg BW, the average energy content of the 14 sources was 8.42 Mcal DE/kg, 8.26 Mcal ME/kg, and 7.27 Mcal NE/kg. At 50 kg BW, the average energy content was 8.45 Mcal DE/kg, 8.28 Mcal ME/kg, and 7.29 Mcal NE/kg. At 13 kg BW, the variation of dietary fat DE content was explained by DE (Mcal/kg) = 9.363 + [0.097 × (FFA, %)] - [0.016 × omega-6:omega-3 fatty acids ratio] - [1.240 × (arachidic acid, %)] - [5.054 × (insoluble impurities, %)] + [0.014 × (palmitic acid, %)] ( = 0.008, = 0.82). At 50 kg BW, the variation of dietary fat DE content was explained by DE (Mcal/kg) = 8.357 + [0.189 × U:S] - [0.195 × (FFA, %)] - [6.768 × (behenic acid, %)] + [0.024 × (PUFA, %)] ( = 0.002, = 0.81). In summary, the chemical composition of dietary fat explained a large degree of the variation observed in the energy content of dietary fat sources at both 13 and 50 kg BW.


Asunto(s)
Grasas de la Dieta/metabolismo , Metabolismo Energético , Aceites de Plantas/metabolismo , Porcinos/metabolismo , Tejido Adiposo/metabolismo , Alimentación Animal/análisis , Animales , Dieta/veterinaria , Digestión , Grasas/metabolismo , Aceites de Pescado/metabolismo , Masculino
4.
J Anim Sci ; 95(8): 3609-3619, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28805896

RESUMEN

The objective was to investigate the of effect chemical composition of dietary fat on transcription of genes involved in lipid metabolism in adipose tissue and the liver via transcriptional profiling in growing pigs. A total of 48 Genetiporc 6.0 × Genetiporc F25 (PIC, Inc., Hendersonville, TN) barrows (initial BW of 44.1 ± 1.2 kg) were randomly allotted to 1 of 6 dietary treatments. Each experimental diet included 95% of a corn-soybean meal basal diet and 5% cornstarch (control; CNTR), animal-vegetable blend (AV), coconut oil (COCO), corn oil (COIL), fish oil (FO), or tallow (TAL). Pigs were sacrificed on d 10 (final BW of 51.2 ± 1.7 kg) to collect tissues. Expression normalization across samples was performed by calculating a delta cycle threshold (ΔCt) value using . Delta delta cycle threshold (ΔΔCt) values were expressed relative to the CNTR treatment. In adipose tissue, adding dietary fat, regardless of the source, decreased the mRNA abundance of compared with the CNTR ( = 0.014). Pigs fed a COIL-based diet tended to have greater adipose tissue expression of ( = 0.071) than pigs fed the other dietary fat sources tested. Abundance of mRNA was greater in adipose tissue of barrows a fed COIL-based diet than barrows fed CNTR or FO-based diets ( = 0.047). In the liver, adding dietary fat, regardless of source, increased the mRNA abundance of , , , , , and ( ≤ 0.020) and tended to increase the abundance of ( = 0.071) and ( = 0.086) compared with the CNTR. Pigs fed a TAL-based diet had greater hepatic transcription of than pigs fed CNTR-, COCO-, or FO-based diets ( = 0.013). Hepatic transcription of tended to be greater in pigs fed COCO than in pigs fed other dietary fat sources ( = 0.074). Dietary omega-3 fatty acid content tended to negatively correlate with mRNA abundance of ( = 0.065) in adipose tissue and ( = 0.063) in the liver. Dietary fat SFA content was negatively correlated with in the liver ( ≤ 0.039). Dietary fat MUFA content tended to be positively correlated with , , and mRNA abundance in the liver ( ≤ 0.100). To conclude, the intake of omega-3 fatty acids suppressed the mRNA abundance of genes involved in lipolysis in both adipose tissue and the liver. Dietary SFA are greater inhibitors of lipogenesis in adipose tissue than omega-6 fatty acids. Intake of medium-chain fatty acids alters hepatic lipid metabolism differently than intake of long-chain fatty acids.


Asunto(s)
Tejido Adiposo/metabolismo , Grasas de la Dieta/análisis , Metabolismo de los Lípidos/efectos de los fármacos , Hígado/metabolismo , Porcinos/metabolismo , Animales , Estudios de Cohortes , Dieta/veterinaria , Grasas de la Dieta/farmacología , Grasas/farmacología , Ácidos Grasos/metabolismo , Aceites de Pescado/farmacología , Regulación de la Expresión Génica/genética , Lipogénesis/efectos de los fármacos , Lipólisis/efectos de los fármacos , Masculino , Aceites de Plantas/farmacología , ARN Mensajero/análisis , Distribución Aleatoria , Porcinos/genética , Transcripción Genética
5.
J Anim Sci ; 94(12): 5248-5261, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28046146

RESUMEN

The pig industry uses a variety of fat sources (FS) and fat levels (FL) in diets to increase energy content. The objective was to investigate the impact of FS and FL on rate and efficiency of gain, apparent total tract digestibility of dietary fat, and pork fat composition and test dietary predictors of carcass iodine value (IV). A total of 1,213 pigs (PIC 280 × PIC Camborough 42; PIC, Inc., Hendersonville, TN) with an initial BW of 32.0 ± 0.4 kg were randomly allotted to 1 of 6 dietary treatments on d 0. Treatments were arranged as a 2 × 3 factorial, with 2 FS, choice white grease (CWG; IV = 66.8) and corn oil (COIL; IV = 123.2), and 3 FL, 2, 4, or 6%. Ten pens of approximately 20 pigs each (0.70 m/pig) were randomly assigned to each of the 6 treatments. All pigs were on trial for 105 d. Pigs were harvested in 1 of 3 marketing pulls, to achieve an ideal market BW across differing rates of gain, at which time belly fat samples were collected (d 105 [457 pigs], 117 [309 pigs], or 134 [432 pigs]). Diet and belly fat samples were analyzed for fatty acid profile. Daily rate of gain was not impacted by FS or FL ( ≤ 0.325). Increasing FL and dietary energy concentration increased G:F ( < 0.001). No difference was evident for G:F between FS ( = 0.107). Increasing FL of CWG resulted in greater daily intake of SFA and MUFA than increasing FL of COIL ( < 0.001). Increasing levels of COIL resulted in greater daily intake of PUFA than increasing levels of CWG ( ≤ 0.012). Feeding CWG tended to result in great caloric efficiency adjusted for carcass yield than feeding COIL ( = 0.074). The inclusion of COIL instead of CWG tended to increase true total tract digestion of acid hydrolyzed ether extract on d 39 ( = 0.066) but not on d 104 ( = 0.402). Increasing COIL increased carcass IV at a greater magnitude than increasing CWG, resulting in a FS × FL interaction on d 105, 117, and 134 ( < 0.001). Dietary linoleic acid concentration and daily intake had a stronger linear relationship than IV product (IVP; = 0.95 vs. = 0.94 vs. = 0.85, respectively). In conclusion, limiting linoleic acid dietary concentration and intake is key to lowering carcass IV. To meet a carcass IV standard of 74 g/100 g, linoleic acid concentration had to be <3.4% and intake had to be <88 g/d. Dietary linoleic acid is a superior predictor of carcass IV compared with IVP, especially when high-fat diets are used.


Asunto(s)
Grasas de la Dieta/metabolismo , Yodo/metabolismo , Porcinos/fisiología , Tejido Adiposo/metabolismo , Alimentación Animal , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Composición Corporal , Dieta/veterinaria , Dieta Alta en Grasa/veterinaria , Grasas de la Dieta/análisis , Femenino , Yodo/análisis , Masculino , Distribución Aleatoria , Carne Roja/análisis
6.
J Anim Sci ; 94(11): 4688-4703, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27898929

RESUMEN

Heat stress (HS) results in major losses to the pork industry via reduced growth performance and, possibly, carcass fat quality. The experimental objective was to measure the effects of HS on the pig's response to dietary fat in terms of lipid digestion, metabolism, and deposition over a 35-d finishing period. A total of 96 PIC 337 × C22/C29 (PIC, Inc., Hendersonville, TN) barrows (initial BW of 100.4 ± 1.2 kg) were randomly allotted to 1 of 9 treatments arranged as a 3 × 3 factorial: thermoneutral (TN; constant 24°C; ad libitum access to feed), pair-fed thermoneutral (PFTN; constant 24°C; limit fed based on previous HS daily feed intake), or HS (cyclical 28°C nighttime, 33°C from d 0 to 7, 33.5°C from d 7 to 14, 34°C from d 14 to 21, 34.5°C from d 21 to 28, and 35°C from d 28 to 35 daytime; ab libitum access to feed) and diet (a corn-soybean meal-based diet with 0% added fat [CNTR], CNTR with 3% added tallow [TAL; iodine value {IV} = 41.8], or CNTR with 3% added corn oil [CO; IV = 123.0]). No interactions between environment and diet were evident for any major response criteria ( ≥ 0.063). Rectal temperature increased due to HS (39.0°C for HS, 38.1°C for TN, and 38.2°C for PFTN; < 0.001). Heat stress decreased ADFI (27.8%; < 0.001), ADG (0.72 kg/d for HS, 1.03 kg/d for TN, and 0.78 kg/d for PFTN; < 0.001), and G:F (0.290 for HS, 0.301 for TN, and 0.319 for PFTN; = 0.006). Heat stress barrows required 1.2 Mcal of ME intake more per kilogram of BW gain than PFTN ( < 0.001). Heat stress tended to result in the lowest apparent total tract digestibility of acid hydrolyzed ether extract (AEE; 59.0% for HS, 60.2% for TN, and 61.4% for PFTN; = 0.055). True total tract digestibility (TTTD) of AEE of CO-based diets (99.3%) was greater than that of CNTR (97.3%) and TAL-based diets (96.3%; = 0.012). Environment had no impact on TTTD of AEE ( = 0.118). Environment had no impact on jowl IV at market (69.2 g/100 g for HS, 69.3 g/100 g for TN, and 69.8 g/100 g for PFTN; = 0.624). Jowl IV at market increased with increasing degree of unsaturation of the dietary fat (68.5 g/100 g for CNTR, 68.2 g/100 g for TAL, and 71.5 g/100 g for CO; < 0.001). Heat stress decreased mRNA abundance of and ( ≤ 0.041). Heat stress and CO increased mRNA abundance of ( ≤ 0.047), and CO increased abundance of ( = 0.011). In conclusion, HS does not alter the pig's response to dietary fat. However, HS leads to reduced ADG, ADFI, G:F, and caloric efficiency and a suppression of mRNA abundance of genes involved in the lipolytic cascade, which resulted in a phenotype that was fatter than PFTN.


Asunto(s)
Grasas de la Dieta/farmacología , Respuesta al Choque Térmico , Calor/efectos adversos , Porcinos/fisiología , Alimentación Animal/análisis , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Composición Corporal/fisiología , Temperatura Corporal , Dieta/veterinaria , Grasas de la Dieta/administración & dosificación , Digestión , Grasas/metabolismo , Conducta Alimentaria , Respuesta al Choque Térmico/fisiología , Metabolismo de los Lípidos , Masculino , Distribución Aleatoria , Porcinos/crecimiento & desarrollo
7.
J Anim Sci ; 93(1): 247-57, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25568373

RESUMEN

The inclusion of unsaturated fats in pig diets has raised issues related to pork carcass fat quality. The objective of this experiment was to understand how withdrawal from the diet of unsaturated dietary fat before slaughter impacts the composition of jowl fat during the growth cycle and at market. Fifty individually housed pigs (PIC 337 × C22/29; initial BW = 59.3 ± 0.55 kg) were allotted based on sex and initial BW to 10 treatments for an 82-d experiment as follows: 3 dietary fat withdrawal times before slaughter (21, 42, or 63 d) by 3 dietary fat unsaturation loads (DFUL), which includea high intake of unsaturated fatty acids supplied through an inclusion of 5% corn oil (HIGH), a high intake of a mixture of saturated and unsaturated fatty acids supplied through an inclusion of 5% animal-vegetable blend (MED), and a moderate intake of unsaturated fatty acids supplied through an inclusion of 2.5% corn oil (LOW). Pigs were weighed and jowl adipose samples were collected on d 0, 21, 42, and 63 and at harvest on d 82. Data were analyzed using PROC MIXED with treatment and sex as fixed effects. At market (d 82), increasing the withdrawal of dietary fat further away from market increased 18:1 (P = 0.045) and tended to increase 14:0 concentrations (P = 0.054). It also significantly decreased 18:2 (P < 0.001) and tended to decrease 18:3 concentrations (P = 0.081). A HIGH DFUL resulted in the greatest 18:2 concentrations in jowl fat followed by LOW; MED resulted in the lowest 18:2 levels (P < 0.001). Dietary fat withdrawal before market significantly reduced carcass iodine value (IV) measured at d 82 (P = 0.006). In conclusion, elevated 18:2 intake makes lowering carcass IV in the depot fat very difficult and may take as long as 61 d. The withdrawal of unsaturated dietary fat apparently altered the fat depot to be more reflective of fat synthesized de novo, resulting in a more saturated depot fat. Importantly, this alteration of deposited fat composition did not translate into improved belly firmness, depth, weight, or fat color.


Asunto(s)
Tejido Adiposo/efectos de los fármacos , Composición Corporal/efectos de los fármacos , Dieta/veterinaria , Grasas Insaturadas en la Dieta/farmacología , Yodo/análisis , Porcinos/fisiología , Tejido Adiposo/fisiología , Animales , Composición Corporal/fisiología , Distribución de la Grasa Corporal , Peso Corporal/efectos de los fármacos , Peso Corporal/fisiología , Ácidos Grasos/metabolismo , Femenino , Masculino , Factores Sexuales , Porcinos/crecimiento & desarrollo , Factores de Tiempo , Privación de Tratamiento
8.
Metabolism ; 42(3): 269-76, 1993 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8487643

RESUMEN

There is increasing evidence that a link between the polyol pathway and prostaglandins is important in the pathogenesis of diabetic nephropathy. The presence of the polyol pathway in the kidneys of normal animals, the galactose-fed rat, and animals with experimental diabetes has been established. While aldose reductase (AR) immunoreactive protein (AR-IRP) and AR mRNA are expressed at high levels in renal medulla, the sites of AR synthesis and regulation and metabolic consequences of AR activity in renal cortex are uncertain. The present study was conducted to test the hypothesis that AR expression and PGE2 production are coordinately regulated in glomerular mesangial cells. To test this hypothesis, we measured AR-IRP, AR mRNA, and PGE2 production in mesangial cells isolated from rats maintained on diets containing normal chow (MC-N), 50% galactose (MC-G), and 50% dextrin (MC-D). The rank order for each parameter studied (AR-IRP, AR mRNA, PGE2) was MC-N > MC-G > MC-D. Western blot analysis demonstrated that MC-N (optical density [OD] 1.0), MC-G (OD 0.59), and MC-D (OD 0.25) express AR-IRP. Slot-blot analyses demonstrated that levels of AR mRNA were greatest in MC-N (1.0), intermediate in MC-G (0.49), and lowest in MC-D (0.31). Ribonuclease (RNase) protection analyses demonstrated a similar pattern of AR mRNA expression, with MC-N at 1.0, MC-G at 0.60, and MC-D at 0.33. PGE2 production (pg/5 x 10(4) cells/30 min) was highest in MC-N (278 +/- 29), intermediate in MC-G (110 +/- 9), and lowest in MC-D (37 +/- 4).(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Aldehído Reductasa/análisis , Dinoprostona/metabolismo , Mesangio Glomerular/citología , Mesangio Glomerular/metabolismo , Aldehído Reductasa/genética , Aldehído Reductasa/metabolismo , Alimentación Animal , Animales , Western Blotting , Células Cultivadas , Dextrinas/metabolismo , Dextrinas/farmacología , Galactosa/metabolismo , Galactosa/farmacología , Expresión Génica , Mesangio Glomerular/química , Masculino , Microscopía Electrónica de Rastreo , Polímeros/metabolismo , ARN Mensajero/análisis , ARN Mensajero/genética , Radioinmunoensayo , Ratas , Ratas Sprague-Dawley
9.
Toxicol Sci ; 54(2): 408-15, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10774823

RESUMEN

In vitro and in vivo studies evaluated neuropathy target esterase (NTE) inhibition and aging (i.e., loss of reactivation potential) by analytical and technical grade racemic and resolved L-(-) and D-(+) isomers of methamidophos (O,S-dimethyl phosphoramidothioate). For studies in vitro, microsomal protein from phenobarbital-induced livers was isolated from chick embryos and NTE inhibition assays were performed using chick embryo brain homogenate treated with 1 or 5 mM methamidophos (with and without metabolic enzymes); for studies in vivo, hens received 30 to 35 mg/kg methamidophos injected into the pectoral muscle. NTE aging in hens was assessed 24 h later or after 30 min to 1 h incubation in vitro using solutions of potassium fluoride (KF) reactivator. Technical methamidophos produced significantly higher levels of aged-inhibited NTE than analytical methamidophos or isolated optical isomers. In vivo, technical methamidophos produced 61% total NTE inhibition with 18% aged and 43% unaged NTE; hens receiving analytical grade averaged 6% aged, 52% unaged, and 58% total NTE inhibition. Results for 1 mM analytical methamidophos in vitro were 5% aged, 54% unaged, and 59% total inhibition; for 1 mM technical methamidophos, values averaged 11% aged, 50% unaged, and 60% total NTE inhibition. The degree of NTE aging obtained both in vivo and in vitro for the isolated D-(+) and L-(-) isomers never exceeded that obtained using analytical grade. These data indicate that impurities in methamidophos could contribute to OPIDN potential. The in vitro methodology described could be applied to first tier screening for detection of NTE inhibition and aging, thus reducing the need for whole-animal testing for OPIDN.


Asunto(s)
Encéfalo/efectos de los fármacos , Hidrolasas de Éster Carboxílico/metabolismo , Reactivadores Enzimáticos/metabolismo , Insecticidas/toxicidad , Síndromes de Neurotoxicidad/enzimología , Compuestos Organotiofosforados/toxicidad , Animales , Encéfalo/enzimología , Hidrolasas de Éster Carboxílico/antagonistas & inhibidores , Embrión de Pollo , Pollos , Contaminación de Medicamentos , Activación Enzimática , Inhibidores Enzimáticos/toxicidad , Cromatografía de Gases y Espectrometría de Masas , Degeneración Nerviosa/inducido químicamente , Estereoisomerismo
10.
Neurotoxicology ; 9(2): 181-7, 1988.
Artículo en Inglés | MEDLINE | ID: mdl-3205428

RESUMEN

Atropine is often given as an antidote for acute cholinergic effects in studies of a delayed neuropathy (OPIDN) caused by some organophosphorus esters. These experiments examined if atropine would also affect the onset and/or severity of signs of OPIDN. Chickens were given one to six 200 micrograms/kg doses of diisopropyl phosphorofluoridate (DFP) with or without 20 mg/kg atropine (IM). Locomotion, brain neurotoxic esterase (NTE) activity, and histology of the nervous system were examined. The results demonstrated that atropine treatments delayed onset of the signs of OPIDN and may have slightly increased brain NTE activity in vivo. Relatively high levels (Ki: approximately 3.0 mM) of atropine inhibited NTE activity in vitro.


Asunto(s)
Atropina/farmacología , Isoflurofato/toxicidad , Enfermedades del Sistema Nervioso/inducido químicamente , Sistema Nervioso/efectos de los fármacos , Animales , Pollos , Femenino , Isoflurofato/administración & dosificación , Sistema Nervioso/patología , Enfermedades del Sistema Nervioso/patología
11.
Neurotoxicology ; 11(3): 483-91, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-2284053

RESUMEN

Reports that near-lethal doses of the pesticide methamidophos (O,S-dimethyl phosphoramidothioate) caused a delayed neurotoxicity (OPIDN) in humans and that another phosphoramidate, isofenphos, caused OPIDN in the hen at high doses, prompted a study of the abilities of acephate (O,S-dimethyl acetylphosphoramidothioate) to inhibit brain acetylcholinesterase (AChE) and neuropathy target esterase (NTE) in vivo. Hens were treated orally with 5-700 mg/kg of acephate, or im with 50-200 micrograms/kg of diisopropyl-fluorophosphate (DFP, positive control) and sacrificed 24 hr later. Brain homogenates were assayed for AChE as an estimate of acute toxicity, for NTE to indicate acephate's potential to cause OPIDN, and for residues of acephate and its metabolite methamidophos. A range finding study confirmed the LD50 level for acephate was approximately 800 mg/kg. Regression analyses indicated an ID50 (a dose that inhibits 50% of activity) for acephate inhibition of AChE of 10 mg/kg and an extrapolated ID50 for inhibition of NTE of 1300 mg/kg, almost twice the LD50. In contrast, ID50 values for DFP were similar for AChE (146 micrograms/kg) and NTE (132 micrograms/kg). Brain methamidophos levels were 10 to 16 percent of the total acephate plus methamidophos brain concentration. The lower the dose of acephate, the higher was the relative percentage of methamidophos. The results show acephate is a more potent inhibitor of AChE than it is of NTE in hens and suggest it would be difficult to administer a single dose of acephate sufficient to cause OPIDN without killing the animal.


Asunto(s)
Encéfalo/efectos de los fármacos , Hidrolasas de Éster Carboxílico/antagonistas & inhibidores , Inhibidores de la Colinesterasa , Insecticidas/toxicidad , Compuestos Organotiofosforados/toxicidad , Animales , Encéfalo/enzimología , Pollos , Femenino , Insecticidas/metabolismo , Compuestos Organotiofosforados/metabolismo , Fosforamidas
12.
Rev Environ Contam Toxicol ; 146: 1-24, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8714219

RESUMEN

Mevinphos (trade name, Phosdrin), a category 1 organophosphorus insecticide, has been used mainly as a cleanup pesticide for vegetable crops. A risk assessment for occupational and dietary exposure to mevinphos was initiated because of the high acute toxicity of the compound. Repetitive dosing with mevinphos did not cause any discernible histopathological effects in mice or rats, nor was it oncogenic in either species. The principal toxic effects of mevinphos, both short- and long term, were due to inhibition of cholinesterase activity. Consequently, potential adverse effects from short-term exposures were the primary concern. A human no-observed-effect level (0.025 mg/kg) for cholinergic signs was used as the regulatory basis for calculating margins of safety (MOSs) for potential acute dietary and short-term occupational exposures. Estimates of exposure to mixer/loaders, pilots, and flaggers associated with aerial application of mevinphos were based on passive dosimetry. Because no acceptable exposure studies for work tasks associated with ground application of mevinphos were available, surrogate data based on ground application of oxydemeton-methyl were used. Exposure estimates for field workers and harvesters relied on measured dislodgeable foliar residues of mevinphos and transfer factors generated from studies of other active ingredients. MOSs for mean acute occupational exposure of mixer/loader/applicators associated with ground application and of harvesters working in fruit trees were less than the value conventionally recommended to protect people from the toxic effects of mevinphos. MOSs for the 95th percentile of short-term worker exposure for all mixer/loader work categories associated with mevinphos application were also inadequate. Calculated MOSs for potential acute dietary exposure to measured residue levels of mevinphos were adequate for the various population subgroups. However, 25 of the USEPA tolerances for mevinphos on agricultural commodities were not adequate to protect for the toxic effects of mevinphos from theoretical acute dietary exposure to one or more population subgroups if commodities are consumed with residues at the tolerance level. When the mean short-term occupational exposures were combined with potential acute dietary exposure, the MOSs for mixer/loaders engaged in aerial applications, as well as ground applications, were inadequate to protect people from the toxic effects of mevinphos. As mitigation of the estimated excessive occupational exposures did not appear possible, both California and the USEPA were preparing to cancel registration of the product. However, an agreement was worked out between the manufacturer and the two agencies that ended production for domestic use but allowed existing stocks in the channels of trade to continue to be used for a limited period.


Asunto(s)
Dieta/efectos adversos , Insecticidas/efectos adversos , Mevinfos/efectos adversos , Exposición Profesional , Animales , Relación Dosis-Respuesta a Droga , Humanos , Insecticidas/toxicidad , Mevinfos/toxicidad , Medición de Riesgo
13.
J Air Waste Manag Assoc ; 50(4): 522-8, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10786003

RESUMEN

Partially speciated hydrocarbon (HC) emissions data from several small utility engines, as measured by a Fourier Transform Infrared analyzer, are presented. The engines considered have nominal horsepower ratings between 3.7 and 9.3 kW. Both side-valve and overhead-valve engines are studied, and four different fuels are used in the engines. The results indicate that the small HCs present in the exhaust tend to be in the form of either methane or unsaturated HCs. Other small alkanes, such as ethane and propane, are present in only relatively small concentrations. In terms of ozone formation potential, the HCs in the form of methane will lead to little ozone, but the distribution of the C2 and C3 species is not ideal from an ozone reduction stand-point. It is also found that the presence of oxygen in the fuels appears to lead to somewhat more complete combustion, although the effects are not large. Finally, the overhead-valve engines appear to have lower HC emissions than side-valve engines, which is primarily due to higher operating A/F ratios and the engine geometry.


Asunto(s)
Contaminación del Aire/análisis , Hidrocarburos/análisis , Emisiones de Vehículos/análisis , Diseño de Equipo , Vehículos a Motor , Ozono/análisis
14.
J Anim Sci ; 92(12): 5485-95, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25367509

RESUMEN

The increased inclusion of unsaturated fats in pig diets has raised issues related to pork carcass fat quality. The objective of this experiment was to more precisely measure how differing levels of daily fatty acid intake alters the fatty acid composition in 3 different fat depots. A total of 42 gilts and 21 barrows (PIC 337×C22/29) with an average initial weight of 77.80±0.38 kg were allotted randomly based on sex and BW to 7 treatments: 3 and 6% of each of tallow (TAL; iodine value [IV]=41.9), choice white grease (CWG; IV=66.5), or corn oil (CO; IV=123.1) and a control (CNTR) corn-soybean meal-based diet with no added fat. Pigs were individually housed to allow accurate measurement of individual feed intake, in particular, daily dietary fatty acid and energy intake. Fat samples were collected from the jowl, belly, and loin at slaughter. Diet and carcass fat samples were analyzed for IV. Belly weights were recorded at slaughter along with a subjective belly firmness score (1=firmest to 3=least firm). Carcass lipid IV was increased (P<0.001) by increasing the degree of unsaturation of the dietary fat source (66.8, 70.3, and 76.3 for TAL, CWG, and CO, respectively). Carcass lipid IV for TAL and CWG was not affected (P>0.05) by inclusion levels; however, carcass lipid IV was greater (P<0.001) in pigs fed 6 than 3% CO (80.0 vs. 72.6), and carcasses of gilts had greater IV (P<0.001) than carcasses of barrows (71.5 vs. 69.1). Increasing the level of TAL and CO but not CWG from 3 to 6% decreased the apparent total tract digestibility of GE, resulting in a source×level interaction (P<0.05). Dietary fat source had no effect (P≥0.66) on apparent total tract digestibility of either DM or GE, but feeding 6% dietary fat increased G:F (P=0.006) over pigs fed 3% fat (0.358 vs. 0.337). Of all the fatty acids measured, only linoleic acid intake presented a reasonable coefficient of determination (R2=0.61). Overall, IV product (IVP) was approximately equal to linoleic acid intake as a predictor of carcass IV (R2=0.93 vs. R2=0.94). When inclusion of dietary fat and PUFA intake increased, IVP placed more emphasis on the dietary fat inclusion level rather than the dietary fat composition. Linoleic acid intake corrected the overemphasis placed on dietary fat inclusion by IVP. To conclude, linoleic acid intake showed a strong relationship with carcass IV and can be used as a predictor.


Asunto(s)
Tejido Adiposo/efectos de los fármacos , Composición Corporal/efectos de los fármacos , Grasas de la Dieta/farmacología , Ácidos Grasos/farmacología , Yodo/metabolismo , Carne , Sus scrofa/crecimiento & desarrollo , Análisis de Varianza , Animales , Peso Corporal/efectos de los fármacos , Dieta/veterinaria , Ingestión de Energía/fisiología , Grasas/análisis , Lípidos/análisis , Espectrofotometría/veterinaria , Porcinos
15.
Appl Opt ; 37(30): 7076-9, 1998 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-18301527

RESUMEN

As much as 1.6-W average output power was emitted in a simple setup from a diffusion-bonded Nd:YAG rod with 70-100-ns Q-switched pulses at 946 nm and repetition frequencies between 15 and 45 kHz at 22-W incident diode-pump power. A Cr(4+):YAG crystal with a bleachable loss of approximately 2.5% and a length of 0.5 mm was used as a saturable absorber. The extraction efficiency was 47% in comparison with the continuous-wave laser output power of 3.37 W in the free-running regime.

16.
Opt Lett ; 24(4): 205-7, 1999 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-18071455

RESUMEN

We report on efficient intracavity frequency doubling of a cw diode-pumped Nd:YAG laser on the (4)F(3/2)?(4)I(9/2) laser transition at 946 nm. The nonlinear crystal used in the experiments was a first-order quasi-phase-matched flux-grown KTiOPO(4) crystal (period, 6.09mum ; thickness, 1 mm; length, 9 mm). The fluctuations in the generated second-harmonic wave were lower than 3% at output powers of as much as 500 mW. The overall optical-to-optical efficiency was 5.7%. A maximum output power of 740 mW of blue light was generated, which was stable for only 0.5 min. The decrease the output power at this power level was attributed to heating and thermal lensing in the periodically poled KTiOPO(4) crystal. The short-term behavior of the second-harmonic wave exhibited switching between a cw mode and chaotic intensity fluctuations.

17.
Opt Lett ; 21(19): 1567-9, 1996 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-19881727

RESUMEN

We passively mode locked a diode-pumped neodymium lanthanum scandium borate laser with an antiresonant Fabry-Perot saturable absorber and achieved 2.8-ps pulses at an average output power of 400 mW and a pump power of 1.2 W. With Ti:sapphire laser pumping we obtained pulses as short as 1.6 ps. Intracavity doubling produced 190 mW of 531-nm light for a diode-pump power of 1.2 W, resulting in a conversion efficiency of 48% with respect to the fundamental and 16% with respect to the diode-pump power. Noise characterization of the laser demonstrates a trade-off between high conversion efficiency and low intensity noise.

18.
J Toxicol Environ Health ; 23(1): 115-26, 1988.
Artículo en Inglés | MEDLINE | ID: mdl-3336056

RESUMEN

Hens were repeatedly exposed to paraoxon (PO, phosphonothioic acid, diethyl paranitrophenyl ester), the chemical warfare agent VX/phosphorofluoridic acid, methyl-S-(2-[bis(1-methylethyl)amino/ethyl)O-ethyl ester], or the neuropathic DFP [phosphorofluoridic acid, bis(1-methylethyl)ester] as evidence was sought for nerve or other tissue damage following long-term treatments at high dose levels. Thirty-day and 90-d trials were performed in which each bird was injected 3 or 5 times per week with atropine as protection, weighed, their eggs collected, and their blood enzymes (cholinesterases creatine kinase, and lactic dehydrogenase) and locomotion periodically examined. Muscle and brain enzymes were assayed at the end of the experiments. Doses of PO and VX were at or above LD50 levels. DFP doses were lowered with each run to estimate a no-observable-effect level for organophosphate-induced delayed-neuropathy (OPIDN). No abnormalities attributable to repeated exposures to either PO or VX were found, even though acute, short-term symptoms of toxicity appeared after each injection. No evidence for OPIDN was obtained with repeated exposures to PO and VX under conditions where OPIDN was caused by DFP. Histological signs of OPIDN appeared in the spinal cord without gross symptoms of ataxia following repeated treatments of 25 mg/kg of DFP. The results of one experiment suggested that exposure to protective injections of atropine delays the appearance of the locomotor symptoms of the DFP-induced neuropathy.


Asunto(s)
Compuestos Organofosforados/toxicidad , Animales , Encéfalo/enzimología , Pollos , Colinesterasas/sangre , Colinesterasas/metabolismo , Creatina Quinasa/sangre , Creatina Quinasa/metabolismo , Femenino , L-Lactato Deshidrogenasa/sangre , L-Lactato Deshidrogenasa/metabolismo , Locomoción/efectos de los fármacos , Músculos/enzimología , Compuestos Organofosforados/administración & dosificación , Compuestos Organotiofosforados/administración & dosificación , Compuestos Organotiofosforados/toxicidad , Paraoxon/administración & dosificación , Paraoxon/toxicidad , Factores de Tiempo
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