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1.
Clin Ther ; 42(10): 1946-1954.e2, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32980184

RESUMEN

PURPOSE: LC28-0126 is a reactive oxygen species scavenger being developed for the treatment of various conditions caused by oxidative stress, such as oral mucositis, graft-versus-host disease, and lethal reperfusion injury in acute myocardial infarction. The aim of this study was to assess the tolerability and pharmacokinetic properties of LC28-0126 with multiple IV administrations in healthy male subjects. METHODS: A dose-block-randomized, double-blind, placebo-controlled, multiple ascending-dose study was conducted. Subjects received 3-, 10-, 20-, or 30-mg doses of LC28-0126 or inactive control vehicle, infused over 30 min, once daily for 7 days. Blood and urine samples were collected for pharmacokinetics assessment. Tolerability was assessed by the documentation of adverse events, including abnormal findings on physical examination, vital sign measurements, blood oxygen saturation monitoring, 12-lead ECG, continuous ECG monitoring, and clinical laboratory testing. FINDINGS: A total of 32 subjects completed the study. After multiple dosing, the plasma concentration of LC28-0126 showed a steep decrease after infusion, followed by slow elimination. Systemic exposure of LC28-0126 was increased proportionally to doses ranging from 3 to 30 mg. The accumulation ratios were 2.58-2.79 on multiple dosing. The fractions excreted unchanged in urine were found to be <5%. All reported drug-related adverse events were injection-site reactions, and no serious adverse events were reported. IMPLICATIONS: Multiple administrations of LC28-0126 exhibited a dose-proportional pharmacokinetic profile and were well tolerated at a dose range of 3-30 mg. ClinicalTrials.gov identifier: NCT03196804.


Asunto(s)
Hidrocarburos Halogenados/administración & dosificación , Cetonas/administración & dosificación , Adulto , Área Bajo la Curva , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Electrocardiografía , Humanos , Hidrocarburos Halogenados/efectos adversos , Hidrocarburos Halogenados/farmacocinética , Cetonas/efectos adversos , Cetonas/farmacocinética , Masculino , Adulto Joven
2.
Chem Res Toxicol ; 33(9): 2401-2407, 2020 09 21.
Artículo en Inglés | MEDLINE | ID: mdl-32803957

RESUMEN

Disinfecting drinking water with chlorine inadvertently generates disinfection byproducts (DBPs) which can cause potential adverse health effects to humans. Haloaromatic DBPs are a group of emerging DBPs recently identified, suspected to be substantially more toxic than haloaliphatic DBPs but have not been extensively studied. Simultaneously, service pipelines made of lead materials are widely used in water distribution systems and become a source of dissolved lead (Pb) in tap water. In this study, we investigated the cytotoxicity of nine haloaromatic DBPs and lead ion (Pb2+), both separately as well as in combination, to human epithelial colorectal adenocarcinoma (Caco-2) and neuroblastoma (SH-SY5Y) cells. Results show that the cytotoxicity of the DBPs against Caco-2 cells followed the descending rank order of 2,4,6-triiodophenol ≅ 2,5-dibromohydroquinone > 2,4,6-tribromophenol > 3,5-dibromo-4-hydroxybenzaldehyde ≅ 2,4,6-trichlorophenol > 4-chlorophenol ≅ 3,5-dibromo-4-hydroxybenzoic acid > 2,6-dichlorophenol >5-chlorosalicylic acid, and the cytotoxicity of the DBPs against SH-SY5Y cells followed a similar rank order, 2,4,6-triiodophenol ≅ 2,5-dibromohydroquinone > 2,4,6-tribromophenol > 3,5-dibromo-4-hydroxybenzaldehyde ≅ 2,4,6-trichlorophenol > 4-chlorophenol > 3,5-dibromo-4-hydroxybenzoic acid > 2,6-dichlorophenol ≅ 5-chlorosalicylic acid. Lead in water did not change the toxicity of 3,5-dibromo-4-hydroxybenzoic acid (to either cell-type) or the toxicity of 4-chlorophenol (to the neuronal cell-type); but Pb2+ exhibited different degrees of synergistic effects with other tested DBPs. The synergism resulted in different rank orders of cytotoxicity against both intestinal and neuronal cells. These data indicate that future prioritization and regulation of emerging haloaromatic DBPs in drinking water should be considered in terms of their own toxicity and combinatorial effects with lead in water.


Asunto(s)
Desinfectantes/farmacología , Hidrocarburos Halogenados/farmacología , Intestino Delgado/efectos de los fármacos , Plomo/farmacología , Neuronas/efectos de los fármacos , Células CACO-2 , Células Cultivadas , Desinfectantes/administración & dosificación , Relación Dosis-Respuesta a Droga , Humanos , Hidrocarburos Halogenados/administración & dosificación , Plomo/administración & dosificación
3.
Regul Toxicol Pharmacol ; 112: 104610, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32032664

RESUMEN

1,4-Dichlorobutane (1,4-DCB) is used as raw materials for drugs, pesticides, fragrances, and chemical fibers, and being used as a solvent. Its toxicity data was insufficient for screening assessment under the Japanese Chemical Substances Control Law. We conducted toxicity tests and hazard classification for screening assessment 1,4-DCB showed negative in the Ames test, positive in the in vitro chromosomal aberrations test with metabolic activation, and negative in the in vivo mouse bone-marrow micronucleus test. The 28-day repeated-dose toxicity study, where male and female rats were administered 1,4-DCB by gavage at 0, 12, 60, and 300 mg/kg/day, showed significant effects on the liver and pancreas from 12 mg/kg/day and kidney at 300 mg/kg/day. Based on periportal hepatocellular hypertrophy and decreased zymogen granules in pancreas, the lowest observed adverse effect level (LOAEL) of 12 mg/kg/day was obtained. The reproductive/developmental toxicity screening study, in which male and female rats were administered 1,4-DCB by gavage at dose of 0, 2.4, 12, and 60 mg/kg/day for 42-46 days, showed that the delivery index was decreased at 60 mg/kg/day without maternal toxicity. Based on the general toxicity, we classified this chemical as hazard class 2, with a D-value (Derived No Effect Level) of 0.002 mg/kg/day.


Asunto(s)
Aberraciones Cromosómicas/efectos de los fármacos , Hidrocarburos Halogenados/toxicidad , Reproducción/efectos de los fármacos , Administración Oral , Animales , Células CHO , Células Cultivadas , Cricetulus , Relación Dosis-Respuesta a Droga , Femenino , Hidrocarburos Halogenados/administración & dosificación , Hígado/efectos de los fármacos , Hígado/metabolismo , Masculino , Páncreas/efectos de los fármacos , Páncreas/metabolismo , Ratas , Ratas Sprague-Dawley , Pruebas de Toxicidad
4.
Am J Drug Alcohol Abuse ; 46(2): 180-183, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31449429

RESUMEN

Background: Computer and electronic duster sprays contain halogenated hydrocarbon gases. Intentional inhalation of computer and electronic duster sprays to induce intoxication, also known as huffing, may cause serious adverse effects and even death.Objectives: Describe computer and electronic duster spray inhalation-related injuries managed at United States (US) emergency departments (EDs).Methods: Data were obtained from the National Electronic Injury Surveillance System (NEISS), a database of consumer product-related injuries collected from the EDs of approximately 100 hospitals in the US. Cases were computer and electronic duster spray inhalation-related injuries included in NEISS during 2001-2017. The distribution by selected variables was determined for the resulting cases as well as a weighted estimate.Results: A total of 320 computer and electronic duster spray inhalation-related injuries were identified, resulting in a national estimate of 14,715 (95% confidence interval 11,120-18,311) such injuries. The annual estimated number of injuries remained low during 2001-2008 then increased during 2008-2017. Of the estimated injury patients, 3.2% were aged 6-12 years, 20.3% 13-19 years, and 76.5% 20-59 years; 65.4% of the patients were male. The disposition of the patient was 71.4% treated and examined and released, 6.9% treated and transferred, 11.6% treated and admitted or hospitalized, 0.7% held for observation, and 8.7% left without being seen.Conclusion: This study suggests that computer and electronic duster spray inhalation (huffing) may be an increasing issue of which hospital EDs and other clinicians should be aware. The pattern of injuries observed may be useful for targeting education, prevention and management activities.


Asunto(s)
Computadores , Bases de Datos Factuales/estadística & datos numéricos , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/epidemiología , Electrónica , Servicio de Urgencia en Hospital/estadística & datos numéricos , Hidrocarburos Halogenados/efectos adversos , Administración por Inhalación , Adolescente , Adulto , Niño , Femenino , Humanos , Hidrocarburos Halogenados/administración & dosificación , Masculino , Persona de Mediana Edad , Factores de Tiempo , Estados Unidos/epidemiología , Adulto Joven
5.
Curr Vasc Pharmacol ; 16(4): 336-343, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29032753

RESUMEN

Halogenated anesthetic agents (desflurane, isoflurane and sevoflurane) may have cardioprotective properties at therapeutic doses against myocardial intraoperative ischemia-reperfusion injury. Cardioprotection mechanisms are related to mitochondrial and anti-apoptotic signaling pathways. Experimentals and human studies have proven that their use may reduce morbidity and mortality in the setting of cardiac surgery, including a reduction in myocardial infarct size and mechanical ventilation needs. In contrast, total intra-venous propofol based anesthesia may be detrimental. In the present review, we show the rationale for the perioperative use of halogenated anesthetics based on mechanisms of action, experimental research and human studies. Considerations and major concerns regarding their use, the present evidence for their use in other areas, such as major non-cardiac surgery and intensive care unit patients, and future perspectives are also discussed.


Asunto(s)
Anestesia por Inhalación/mortalidad , Anestésicos por Inhalación/administración & dosificación , Procedimientos Quirúrgicos Cardíacos/mortalidad , Hidrocarburos Halogenados/administración & dosificación , Anestesia por Inhalación/efectos adversos , Anestésicos por Inhalación/efectos adversos , Animales , Procedimientos Quirúrgicos Cardíacos/efectos adversos , Humanos , Hidrocarburos Halogenados/efectos adversos , Complicaciones Posoperatorias/mortalidad , Complicaciones Posoperatorias/fisiopatología , Complicaciones Posoperatorias/prevención & control , Factores Protectores , Medición de Riesgo , Factores de Riesgo , Resultado del Tratamiento
6.
Curr Vasc Pharmacol ; 16(4): 319-328, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29149820

RESUMEN

The implementation of cardioprotective strategies involving pre-, intra-, and postoperative interventions is key during cardiac surgery requiring extracorporeal circulation (ECC). The primary goal of this study was to review the physiopathology and protection strategies against myocardial damage secondary to ECC during cardiac surgery. The administration halogenated anesthetics for cardiac anesthesia is common place due to their well-known cardioprotective effects and their capacity to ensure hypnosis. An optimal myocardial protection strategy requires that a comprehensive approach should be adopted to cover pre-, intra-, and post-operative interventions. Pre-conditioning and post-conditioning share numerous pathways, mainly based on mitochondrial signaling, antiapoptotic pathways, and reduced inflammatory mediators. However, volatile anesthetic can also be administered during ECC, in which mechanism of action has been scantly investigated, during this period and its biology is still unknown.


Asunto(s)
Anestesia por Inhalación , Anestésicos por Inhalación/administración & dosificación , Procedimientos Quirúrgicos Cardíacos , Oxigenación por Membrana Extracorpórea , Hidrocarburos Halogenados/administración & dosificación , Complicaciones Posoperatorias/prevención & control , Anestesia por Inhalación/efectos adversos , Anestesia por Inhalación/mortalidad , Anestésicos por Inhalación/efectos adversos , Animales , Procedimientos Quirúrgicos Cardíacos/efectos adversos , Procedimientos Quirúrgicos Cardíacos/mortalidad , Oxigenación por Membrana Extracorpórea/efectos adversos , Oxigenación por Membrana Extracorpórea/mortalidad , Humanos , Hidrocarburos Halogenados/efectos adversos , Complicaciones Posoperatorias/mortalidad , Complicaciones Posoperatorias/fisiopatología , Factores de Riesgo , Resultado del Tratamiento
7.
Appl Environ Microbiol ; 82(3): 778-87, 2016 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-26567308

RESUMEN

Bromochloromethane (BCM), an inhibitor of methanogenesis, has been used in animal production. However, little is known about its impact on the intestinal microbiota and metabolic patterns. The present study aimed to investigate the effect of BCM on the colonic bacterial community and metabolism by establishing a Wistar rat model. Twenty male Wistar rats were randomly divided into two groups (control and treated with BCM) and raised for 6 weeks. Bacterial fermentation products in the cecum were determined, and colonic methanogens and sulfate-reducing bacteria (SRB) were quantified. The colonic microbiota was analyzed by pyrosequencing of the 16S rRNA genes, and metabolites were profiled by gas chromatography and mass spectrometry. The results showed that BCM did not affect body weight and feed intake, but it did significantly change the intestinal metabolic profiles. Cecal protein fermentation was enhanced by BCM, as methylamine, putrescine, phenylethylamine, tyramine, and skatole were significantly increased. Colonic fatty acid and carbohydrate concentrations were significantly decreased, indicating the perturbation of lipid and carbohydrate metabolism by BCM. BCM treatment decreased the abundance of methanogen populations, while SRB were increased in the colon. BCM did not affect the total colonic bacterial counts but significantly altered the bacterial community composition by decreasing the abundance of actinobacteria, acidobacteria, and proteobacteria. The results demonstrated that BCM treatment significantly altered the microbiotic and metabolite profiles in the intestines, which may provide further information on the use of BCM in animal production.


Asunto(s)
Microbioma Gastrointestinal/efectos de los fármacos , Microbioma Gastrointestinal/fisiología , Tracto Gastrointestinal/microbiología , Hidrocarburos Halogenados/farmacología , Metaboloma/efectos de los fármacos , Acidobacteria/efectos de los fármacos , Acidobacteria/genética , Acidobacteria/metabolismo , Actinobacteria/efectos de los fármacos , Actinobacteria/genética , Actinobacteria/metabolismo , Animales , Metabolismo de los Hidratos de Carbono/efectos de los fármacos , Ciego/efectos de los fármacos , Ciego/metabolismo , Ciego/microbiología , Euryarchaeota/clasificación , Euryarchaeota/efectos de los fármacos , Euryarchaeota/genética , Euryarchaeota/metabolismo , Fermentación , Microbioma Gastrointestinal/genética , Tracto Gastrointestinal/efectos de los fármacos , Hidrocarburos Halogenados/administración & dosificación , Mucosa Intestinal/metabolismo , Intestinos/efectos de los fármacos , Intestinos/microbiología , Metabolismo de los Lípidos/efectos de los fármacos , Metaboloma/genética , Proteobacteria/efectos de los fármacos , Proteobacteria/genética , Proteobacteria/metabolismo , ARN Ribosómico 16S/metabolismo , Ratas Wistar , Análisis de Secuencia de ADN
8.
Behav Brain Res ; 279: 41-6, 2015 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-25446760

RESUMEN

The selective CRF1 (corticotropin releasing factor type 1) receptor antagonist SSR125543 has been previously shown to attenuate the long-term behavioral and electrophysiological effects produced by traumatic stress exposure in mice. Sleep disturbances are one of the most commonly reported symptoms by people with post-traumatic stress disorder (PTSD). The present study aims at investigating whether SSR125543 (10 mg/kg/day/i.p. for 2 weeks) is able to attenuate sleep/wakefulness impairment induced by traumatic stress exposure in a model of PTSD in mice using electroencephalographic (EEG) analysis. Effects of SSR125543 were compared to those of the 5-HT reuptake inhibitor, paroxetine (10 mg/kg/day/i.p.), and the partial N-methyl-d-aspartate (NMDA) receptor agonist, d-cycloserine (10 mg/kg/day/i.p.), two compounds which have demonstrated clinical efficacy against PTSD. Baseline EEG recording was performed in the home cage for 6h prior to the application of two electric foot-shocks of 1.5 mA. Drugs were administered from day 1 post-stress to the day preceding the second EEG recording session, performed 14 days later. Results showed that at day 14 post-stress, shocked mice displayed sleep fragmentation as shown by an increase in the occurrence of both non-rapid eye movement (NREM) sleep and wakefulness bouts. The duration of wakefulness, NREM and REM sleep were not significantly affected. The stress-induced effects were prevented by repeated administration of SSR125543, paroxetine and D-cycloserine. These findings confirm further that the CRF1 receptor antagonist SSR125543 is able to attenuate the deleterious effects of traumatic stress exposure.


Asunto(s)
Hidrocarburos Halogenados/administración & dosificación , Receptores de Hormona Liberadora de Corticotropina/antagonistas & inhibidores , Receptores de Hormona Liberadora de Corticotropina/fisiología , Trastornos del Sueño-Vigilia/prevención & control , Trastornos por Estrés Postraumático/complicaciones , Estrés Psicológico/complicaciones , Tiazinas/administración & dosificación , Animales , Encéfalo/efectos de los fármacos , Encéfalo/fisiopatología , Cicloserina/administración & dosificación , Modelos Animales de Enfermedad , Electroencefalografía , Electrochoque , Masculino , Ratones , Paroxetina/administración & dosificación , Receptores de N-Metil-D-Aspartato/agonistas , Inhibidores Selectivos de la Recaptación de Serotonina/administración & dosificación , Sueño/efectos de los fármacos , Trastornos del Sueño-Vigilia/etiología , Trastornos del Sueño-Vigilia/fisiopatología , Trastornos por Estrés Postraumático/fisiopatología , Estrés Psicológico/fisiopatología , Vigilia/efectos de los fármacos
9.
Archaea ; 2014: 841463, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24803846

RESUMEN

The aim of this work was to study whether feeding a methanogen inhibitor from birth of goat kids and their does has an impact on the archaeal population colonizing the rumen and to what extent the impact persists later in life. Sixteen goats giving birth to two kids were used. Eight does were treated (D+) with bromochloromethane after giving birth and over 2 months. The other 8 goats were not treated (D-). One kid per doe in both groups was treated with bromochloromethane (k+) for 3 months while the other was untreated (k-), resulting in four experimental groups: D+/k+, D+/k-, D-/k+, and D-/k-. Rumen samples were collected from kids at weaning and 1 and 4 months after (3 and 6 months after birth) and from does at the end of the treating period (2 months). Pyrosequencing analyses showed a modified archaeal community composition colonizing the rumen of kids, although such effect did not persist entirely 4 months after; however, some less abundant groups remained different in treated and control animals. The different response on the archaeal community composition observed between offspring and adult goats suggests that the competition occurring in the developing rumen to occupy different niches offer potential for intervention.


Asunto(s)
Archaea/clasificación , Archaea/aislamiento & purificación , Biodiversidad , Dieta/métodos , Cabras , Hidrocarburos Halogenados/administración & dosificación , Rumen/microbiología , Animales , Archaea/efectos de los fármacos , Archaea/genética , Estudios Longitudinales , Análisis de Secuencia de ADN
10.
Regul Toxicol Pharmacol ; 69(2): 273-8, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24799087

RESUMEN

The threshold of toxicological concern (TTC) concept is a risk assessment tool for substances present at low oral exposure and lacking hazard data. In the past, several thresholds were elaborated by Munro et al. (1996) and Kroes et al. (2004). For these TTC thresholds, the Cramer class III threshold is based on a broad spectrum of substances, including organophosphates. For organophosphates a separate threshold was elaborated by Kroes et al. (2004), however without adjustment of the Cramer class III threshold. Moreover, reference was made by Munro et al. (2008) that for organohalogens a separate threshold also may apply whereas the EFSA (2012) considers that carbamate substances with anti-choline esterase activity can be included in the threshold for organophosphates. In this paper, a reevaluation of the Munro dataset (original TTC database) was performed, focused on the thresholds for organophosphates including carbamates, organohalogens and remaining Cramer class III substances. This way thresholds for each of these groups are elaborated. As a results of the current reevaluation of the Munro dataset, thresholds for life-time exposure are elaborated for the group of organophosphates including carbamates, the group of organohalogens and the remaining Cramer class III substances, being 0.30, 1.5 and 4.0 µg/kg bodyweight/day, respectively.


Asunto(s)
Carbamatos/administración & dosificación , Carbamatos/toxicidad , Bases de Datos Factuales , Hidrocarburos Halogenados/administración & dosificación , Hidrocarburos Halogenados/toxicidad , Organofosfatos/administración & dosificación , Organofosfatos/toxicidad , Medición de Riesgo
11.
Risk Anal ; 32(10): 1784-97, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22640366

RESUMEN

Traditional additivity models provide little flexibility in modeling the dose-response relationships of the single agents in a mixture. While the flexible single chemical required (FSCR) methods allow greater flexibility, its implicit nature is an obstacle in the formation of the parameter covariance matrix, which forms the basis for many statistical optimality design criteria. The goal of this effort is to develop a method for constructing the parameter covariance matrix for the FSCR models, so that (local) alphabetic optimality criteria can be applied. Data from Crofton et al. are provided as motivation; in an experiment designed to determine the effect of 18 polyhalogenated aromatic hydrocarbons on serum total thyroxine (T(4)), the interaction among the chemicals was statistically significant. Gennings et al. fit the FSCR interaction threshold model to the data. The resulting estimate of the interaction threshold was positive and within the observed dose region, providing evidence of a dose-dependent interaction. However, the corresponding likelihood-ratio-based confidence interval was wide and included zero. In order to more precisely estimate the location of the interaction threshold, supplemental data are required. Using the available data as the first stage, the Ds-optimal second-stage design criterion was applied to minimize the variance of the hypothesized interaction threshold. Practical concerns associated with the resulting design are discussed and addressed using the penalized optimality criterion. Results demonstrate that the penalized Ds-optimal second-stage design can be used to more precisely define the interaction threshold while maintaining the characteristics deemed important in practice.


Asunto(s)
Hidrocarburos Aromáticos/administración & dosificación , Hidrocarburos Aromáticos/efectos adversos , Hidrocarburos Halogenados/administración & dosificación , Hidrocarburos Halogenados/efectos adversos , Administración Oral , Animales , Biomarcadores/sangre , Relación Dosis-Respuesta a Droga , Interacciones Farmacológicas , Exposición a Riesgos Ambientales/efectos adversos , Humanos , Modelos Biológicos , Dinámicas no Lineales , Ratas , Ratas Long-Evans , Medición de Riesgo , Tiroxina/sangre
12.
J Dairy Sci ; 95(4): 2027-36, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22459848

RESUMEN

Several technologies have been tested to reduce enteric methanogenesis, but very few have been successfully used in practical conditions for livestock. Furthermore, the consequences of reduced rumen methane production on animal performance and milk quality are poorly understood. The aim of this work was to investigate the effect of feeding bromochloromethane (BCM), a halogenated aliphatic hydrocarbon with potential antimethanogenic activity, to dairy goats on rumen methane production, fermentation pattern, the abundance of major microbial groups, and on animal performance and milk composition. Eighteen goats were allocated to 2 experimental groups of 9 animals each: treated (BCM+) or not (BCM-) with 0.30 g of BCM/100 kg of body weight per day. The BCM was administered per os in 2 equal doses per day from parturition to 2 wk postweaning (10 wk). After weaning, methane emissions were recorded over 2 consecutive days (d 57 and 58 on treatment) in polycarbonate chambers. On d 59, individual rumen fluid samples were collected for volatile fatty acid (VFA) analysis and quantification of bacterial, protozoal, and archaeal numbers by real-time PCR. On d 69 and 70, daily milk production was recorded and samples were collected for determination of fat, protein, lactose, casein, and total solids concentration by infrared spectrophotometry, and fatty acid composition by gas chromatography. Treatment with BCM reduced methane production by 33% (21.6 vs. 14.4 L/kg of DMI) compared with nontreated animals, although it did not affect the abundance of rumen bacteria, protozoa, and total methanogenic archaea. The observed improvement in the efficiency of digestive processes was accompanied by a 36% increase in milk yield, probably due to the more propionic type of rumen fermentation and an increase in VFA production. The increase in milk yield was not accompanied by any changes in the concentrations or yields of fat, protein, or lactose. Despite the substantial decrease in methane production, only minor changes in milk fatty acid profile were observed, suggesting that ruminal biohydrogenation pathways were not affected. Compounds that influence terminal biochemical pathways for methane production deserve further development for future application in the dairy goat sector.


Asunto(s)
Ácidos Grasos/análisis , Cabras/metabolismo , Hidrocarburos Halogenados/administración & dosificación , Metano/biosíntesis , Leche/química , Rumen/metabolismo , Animales , Dieta/veterinaria , Ácidos Grasos Volátiles/análisis , Femenino , Fermentación/efectos de los fármacos , Lactancia/efectos de los fármacos , Rumen/efectos de los fármacos , Rumen/microbiología
13.
Invest New Drugs ; 30(1): 266-72, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20697774

RESUMEN

PURPOSE: This study was to determine the maximum tolerated dose, dose-limiting toxicities, and pharmacokinetic profile of TTI-237, a novel anti-tubulin drug, administered weekly in patients with refractory solid tumors. PATIENTS AND METHODS: Using an accelerated dose escalation design, patients with refractory solid tumors were enrolled in this study and treated with TTI-237 intravenously on days 1, 8 and 15 of a 28-day cycle. The starting dose was 4.5 mg/m(2). Pharmacokinetic studies were performed in patients at all dose levels. RESULT: Twenty-eight patients were enrolled and treated with TTI-237 at dose of 4.5, 9, 15, 22.5 and 31.5 mg/m(2). One dose-limiting toxicity neutropenia fever was observed at 31.5 mg/m(2), and all seven patients developed grade 3 or 4 neutropenia at that dose level. TTI-237 dosage was de-escalated to 22.5 and 18 mg/m(2). Six patients were treated at the 18 mg/m(2) dose level without dose-limiting toxicity prior to trial termination. The mean terminal-phase elimination half-life (t(1/2)) for TTI-237 was 25-29 h, and the mean area under the concentration time curve at 31.5 mg/m(2) was 2,768 ng•h/mL. CONCLUSION: A protocol defined maximum tolerated dose was not determined because of early termination of the TTI-237 trial by the sponsor. 18 mg/m(2) may be a tolerable dose of TTI-237.


Asunto(s)
Antineoplásicos/administración & dosificación , Hidrocarburos Halogenados/administración & dosificación , Neoplasias/tratamiento farmacológico , Triazoles/administración & dosificación , Moduladores de Tubulina/administración & dosificación , Adulto , Anciano , Antineoplásicos/efectos adversos , Antineoplásicos/farmacocinética , Área Bajo la Curva , Esquema de Medicación , Terminación Anticipada de los Ensayos Clínicos , Femenino , Semivida , Humanos , Infusiones Intravenosas , Masculino , Dosis Máxima Tolerada , Persona de Mediana Edad , Neoplasias/patología , Resultado del Tratamiento , Moduladores de Tubulina/efectos adversos , Moduladores de Tubulina/farmacocinética
14.
Psychopharmacology (Berl) ; 215(1): 149-63, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21181124

RESUMEN

RATIONALE: The psychotomimetic effects of cannabis are believed to be mediated via cannabinoid CB1 receptors. Furthermore, studies have implicated CB1 receptors in the pathophysiology of schizophrenia. OBJECTIVE: These studies investigated the effects of the CB1 receptor antagonist, AVE1625, in acute pharmacological and neurodevelopmental models of schizophrenia. AVE1625 was administered to rodents alone or as a co-treatment with clinically used antipsychotic drugs (APDs). METHODS: The antipsychotic potential of AVE1625 was tested using psychotomimetic-induced hyperactivity and latent inhibition (LI) deficit models. The procognitive profile was assessed using hole board, novel object recognition, auditory evoked potential, and LI techniques. In addition, the side-effect profile was established by measuring catalepsy, antipsychotic-induced weight gain, plasma levels of prolactin, and anxiogenic potential. RESULTS: AVE1625 (1, 3, and 10 mg/kg ip), reversed abnormally persistent LI induced by MK-801 or neonatal nitric oxide synthase inhibition in rodents, and improved both working and episodic memory. AVE1625 was not active in positive symptom models but importantly, it did not diminish the efficacy of APDs. It also decreased catalepsy and weight gain induced by APDs, suggesting that it may decrease APD-induced extrapyramidal side effects (EPS) and compliance. Unlike other CB1 antagonists, AVE1625 did not produce anxiogenic-like effects. CONCLUSIONS: These preclinical data suggest that AVE1625 may be useful to treat the cognitive deficits in schizophrenia and as a co-treatment with currently available antipsychotics. In addition, an improved side-effect profile was seen, with potential to ameliorate the EPS and weight gain issues with currently available treatments.


Asunto(s)
Antipsicóticos/efectos adversos , Antipsicóticos/uso terapéutico , Cognición/efectos de los fármacos , Hidrocarburos Halogenados/uso terapéutico , Receptor Cannabinoide CB1/antagonistas & inhibidores , Esquizofrenia/tratamiento farmacológico , Sulfonamidas/uso terapéutico , Estimulación Acústica , Anfetamina/farmacología , Animales , Antipsicóticos/administración & dosificación , Ansiedad/inducido químicamente , Ansiedad/prevención & control , Conducta Animal/efectos de los fármacos , Catalepsia/inducido químicamente , Catalepsia/prevención & control , Condicionamiento Clásico/efectos de los fármacos , Modelos Animales de Enfermedad , Evaluación Preclínica de Medicamentos , Quimioterapia Combinada , Potenciales Evocados Auditivos/efectos de los fármacos , Hidrocarburos Halogenados/administración & dosificación , Hidrocarburos Halogenados/efectos adversos , Masculino , Ratones , Ratones Endogámicos , Ratas , Ratas Sprague-Dawley , Esquizofrenia/metabolismo , Esquizofrenia/fisiopatología , Sulfonamidas/administración & dosificación , Sulfonamidas/efectos adversos , Aumento de Peso/efectos de los fármacos
15.
Am J Drug Alcohol Abuse ; 36(6): 320-4, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20645887

RESUMEN

BACKGROUND: Anecdotal reports and recent medical examiner and poison control center studies suggest that computer duster spray (CDS) inhalation is an emerging public health threat. However, there is a current dearth of empirical data on CDS use. OBJECTIVES: Study aims were to examine the prevalence, frequency, correlates, and modalities of CDS use among a treatment sample of antisocial youth. METHODS: A battery of standardized psychosocial instruments was administered via interview of 723 Missouri adolescents in residential care for antisocial behavior. RESULTS: Lifetime CDS use was prevalent (14.7%) in this young service population (97.7% of whom participated). CDS users were significantly more likely to report histories of perinatal injuries or illness, traumatic experiences, suicidality and physician-diagnosed mental illness, and evidenced higher levels of psychiatric symptoms, antisocial attitudes and behaviors, and polydrug use than CDS nonusers. CONCLUSIONS AND SCIENTIFIC SIGNIFICANCE: CDS use was endemic in this treatment sample of adolescents and associated with a range of clinically significant comorbidities. Current findings describe an underrecognized and potentially dangerous form of substance misuse that has rarely been studied but that may be of growing importance.


Asunto(s)
Hidrocarburos Aromáticos/administración & dosificación , Hidrocarburos Halogenados/administración & dosificación , Abuso de Inhalantes/epidemiología , Trastornos Relacionados con Sustancias/epidemiología , Administración por Inhalación , Adolescente , Trastorno de Personalidad Antisocial/epidemiología , Comorbilidad , Femenino , Humanos , Entrevista Psicológica , Masculino , Escalas de Valoración Psiquiátrica , Salud Pública , Trastornos Relacionados con Sustancias/psicología
16.
J Econ Entomol ; 103(2): 423-32, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20429458

RESUMEN

The efficacy of bistrifluron, a chitin synthesis inhibitor, in cellulose bait pellets was evaluated on the mound-building subterranean termite, Coptotermes acinaciformis (Froggatt). Three concentrations of the bistrifluron were used: 0 (untreated control), 0.5, and 1.0% over an 8 wk period. Both doses of bistrifluron bait eliminated (viz. termites absent from nest or mound) termite colonies: 83% of colonies (10 of 12) were either eliminated or moribund (viz. colony had no reproductive capacity and decreased workforce) after 8 wk, compared with none of the control colonies. The remaining two treated colonies were deemed to be in decline. Early signs that bistrifluron was affecting the colonies included: 3 wk after baiting mound temperatures showed a loss of metabolic heat, 4 wk after baiting foraging activity in feeding stations was reduced or absent, and dissection of two mounds at 4 wk showed they were moribund. Colony elimination was achieved in around half or less the time, and with less bait toxicant, than other bait products tested under similar conditions in the field, because of either the active ingredient, the high surface area of the pellets, or a combination of both. This suggests the sometimes long times reported for control using baits may be reduced significantly. The use of a mound building species demonstrated clearly colony level effects before and after termites stopped foraging in bait stations.


Asunto(s)
Hidrocarburos Halogenados/administración & dosificación , Hidrocarburos Halogenados/farmacología , Insecticidas/administración & dosificación , Insecticidas/farmacología , Isópteros/efectos de los fármacos , Compuestos de Fenilurea/administración & dosificación , Compuestos de Fenilurea/farmacología , Animales , Relación Dosis-Respuesta a Droga , Control de Insectos/métodos
17.
Obesity (Silver Spring) ; 18(10): 1952-8, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20168311

RESUMEN

This is the first study to examine the effect of subchronic olanzapine (OLZ) on energy homeostasis in rats, covering all aspects of energy balance, including energy intake as metabolizable energy, storage, and expenditure. We further analyzed whether, and by which mechanism, the CB1-antagonist AVE1625 might attenuate OLZ-induced body weight gain. For this purpose, we selected juvenile female Hanover Wistar rats that robustly and reproducibly demonstrated weight gain on OLZ treatment, accepting limitations to model the aberrations on lipid and carbohydrate metabolism. Rats received 2 mg/kg OLZ orally twice daily for 12 days. Body weight and body composition were analyzed. Moreover daily food intake, energy expenditure, and substrate oxidation were determined in parallel to motility and body core temperature. OLZ treatment resulted in substantial body weight gain, in which lean and fat mass increased significantly. OLZ-treated rats showed hyperphagia that manifested in increased carbohydrate oxidation and lowered fat oxidation (FO). Energy expenditure was increased, motility decreased, but there was no indication for hypothermia in OLZ-treated rats. Coadministration of OLZ and AVE1625 (10 mg/kg orally once daily) attenuated body weight gain, diminishing the enhanced food intake while maintaining increased energy expenditure and decreased motility. Our data reveal that energy expenditure was enhanced in OLZ-treated rats, an effect not critically influenced by motility. Energy uptake, however, exceeded energy expenditure and led to a positive energy balance, confirming hyperphagia as the major driving factor for OLZ-induced weight gain. Combination of OLZ treatment with the CB1-antagonist AVE1625 attenuated body weight gain in rats.


Asunto(s)
Fármacos Antiobesidad/uso terapéutico , Antipsicóticos/efectos adversos , Benzodiazepinas/efectos adversos , Metabolismo Energético/efectos de los fármacos , Hidrocarburos Halogenados/uso terapéutico , Receptor Cannabinoide CB1/antagonistas & inhibidores , Sulfonamidas/uso terapéutico , Aumento de Peso/efectos de los fármacos , Animales , Fármacos Antiobesidad/administración & dosificación , Fármacos Antiobesidad/farmacología , Antipsicóticos/administración & dosificación , Benzodiazepinas/administración & dosificación , Carbohidratos de la Dieta/metabolismo , Grasas de la Dieta/metabolismo , Ingestión de Energía/efectos de los fármacos , Femenino , Hidrocarburos Halogenados/administración & dosificación , Hidrocarburos Halogenados/farmacología , Hiperfagia/tratamiento farmacológico , Hiperfagia/etiología , Hiperfagia/metabolismo , Obesidad/etiología , Obesidad/metabolismo , Obesidad/prevención & control , Olanzapina , Oxidación-Reducción , Ratas , Ratas Wistar , Sulfonamidas/administración & dosificación , Sulfonamidas/farmacología
18.
Pediatr Emerg Care ; 25(11): 754-7, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19915427

RESUMEN

An 18-year-old man presented to a community emergency department with increasing shortness of breath and fever. His condition was diagnosed, and he was treated as an inpatient for bilateral pneumonia associated with hypoxemia. When his condition became worse, he acknowledged to deliberate inhalation of keyboard cleaner and to having hemoptysis. Before his death on hospital day 11, known causes of alveolar hemorrhage were excluded. We postulated a cause-and-effect relationship, adding alveolar hemorrhage to the known complications of inhalant abuse.


Asunto(s)
Hemoptisis/inducido químicamente , Hidrocarburos Halogenados/envenenamiento , Trastornos Relacionados con Sustancias/complicaciones , Administración por Inhalación , Adolescente , Biopsia , Resultado Fatal , Hemoptisis/diagnóstico , Humanos , Hidrocarburos Halogenados/administración & dosificación , Pulmón/patología , Masculino , Radiografía Torácica , Trastornos Relacionados con Sustancias/diagnóstico , Tomografía Computarizada por Rayos X
19.
Am J Physiol Endocrinol Metab ; 293(3): E826-32, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17595216

RESUMEN

The objective of the present study was to investigate in fed Wistar rats whether the cannabinoid-1 (CB1) receptor antagonist AVE1625 causes primary effects on metabolic blood and tissue parameters as well as metabolic rate, which are independent of reduced caloric intake. After single administration to rats postprandially, AVE1625 caused a slight dose-dependent increase in basal lipolysis. Six hours after single administration, liver glycogen content was dose-dependently reduced to approximately 60% of that of untreated controls. These findings demonstrate a primary acute effect of AVE1625 on induction of 1) lipolysis from fat tissue (increased FFA) and 2) glycogenolysis from the liver (reduced hepatic glycogen). Measured by indirect calorimetry, AVE1625 caused an immediate increase in total energy expenditure, a long-lasting increase of fat oxidation, and a transient increase of glucose oxidation, which were consistent with the acute findings on metabolic blood and tissue parameters. We conclude that, in addition to the well-investigated effects of CB1 receptor antagonists to reduce caloric intake and subsequently body weight, this pharmacological approach is additionally linked to inherently increased lipid oxidation. This oxidation is driven by persistently increased lipolysis from fat tissues, independently of reduced caloric intake, and might significantly contribute to the weight-reducing effect.


Asunto(s)
Peso Corporal/fisiología , Ingestión de Alimentos/fisiología , Ingestión de Energía/fisiología , Metabolismo Energético/fisiología , Hidrocarburos Halogenados/administración & dosificación , Peroxidación de Lípido/fisiología , Receptor Cannabinoide CB1/antagonistas & inhibidores , Receptor Cannabinoide CB1/metabolismo , Sulfonamidas/administración & dosificación , Animales , Peso Corporal/efectos de los fármacos , Ingestión de Alimentos/efectos de los fármacos , Ingestión de Energía/efectos de los fármacos , Metabolismo Energético/efectos de los fármacos , Peroxidación de Lípido/efectos de los fármacos , Masculino , Ratas , Ratas Wistar
20.
Artículo en Inglés | MEDLINE | ID: mdl-17188578

RESUMEN

Quantitative oral dosing in fish can be challenging, particularly with water soluble contaminants, which can leach into the aquarium water prior to ingestion. We applied a method of bioencapsulation using newly hatched brine shrimp (Artemia franciscana) nauplii to study the toxicokinetics of five chlorinated and brominated halogenated acetic acids (HAAs), which are drinking water disinfection by-products. These results are compared to those obtained in a previous study using a polybrominated diphenyl ether (PBDE-47), a highly lipophilic chemical. The HAAs and PBDE-47 were bioencapsulated using freshly hatched A. franciscana nauplii after incubation in concentrated solutions of the study chemicals for 18 h. Aliquots of the brine shrimp were quantitatively removed for chemical analysis and fed to individual fish that were able to consume 400-500 nauplii in less than 5 min. At select times after feeding, fish were euthanized and the HAA or PBDE-47 content determined. The absorption of HAAs was quantitatively similar to previous studies in rodents: rapid absorption with peak body levels occurring within 1-2 h, then rapidly declining with elimination half-life of 0.3-3 h depending on HAA. PBDE-47 was more slowly absorbed with peak levels occurring by 18 h and very slowly eliminated with an elimination half-life of 281 h.


Asunto(s)
Oryzias/fisiología , Contaminantes Químicos del Agua/toxicidad , Acetatos/farmacocinética , Acetatos/toxicidad , Administración Oral , Animales , Artemia , Ritmo Circadiano/fisiología , Composición de Medicamentos , Femenino , Agua Dulce/análisis , Semivida , Hidrocarburos Halogenados/administración & dosificación , Hidrocarburos Halogenados/farmacocinética , Hidrocarburos Halogenados/toxicidad , Masculino , Dinámicas no Lineales , Ratas , Ratas Endogámicas F344 , Contaminantes Químicos del Agua/administración & dosificación , Contaminantes Químicos del Agua/farmacocinética
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