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1.
Surg Endosc ; 32(4): 1820-1827, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-28932941

RESUMEN

INTRODUCTION: This study aims to evaluate the outcomes and utilization of porcine acellular dermal collagen implant (PADCI) during VHR at a large tertiary referral center. METHODS: Records of 5485 patients who underwent VIHR from June 1995 to August 2014 were retrospectively reviewed to identify patients >18 years of age who had VIHR with PADCI reinforcement. Use of multiple mesh reinforcement products, inguinal hernias, and hiatal hernias were exclusion criteria. The primary outcome was hernia recurrence, and secondary outcomes were early complications and surgical site occurrences (SSOs). Uni- and multivariate analyses assessed risk factors for recurrence after PADCI reinforced VIHR. RESULTS: There were 361 patients identified (54.5% female, mean age of 56.7 ± 12.5 years, and mean body mass index (BMI) of 33.0 ± 9.9 kg/m2). Hypertension (49.5%), diabetes (24.3%), and coronary artery disease (14.4%) were the most common comorbidities, as was active smoking (20.7%). Most were classified as American Association of Anesthesiologists (ASA) Class 3 (61.7%). Hernias were distributed across all grades of the ventral hernia working group (VHWG) grading system: grade I 93 (25.7%), grade II 51 (14.1%), grade III 113 (31.3%), and grade IV 6 (1.6%). Most VIHR were performed from an open approach (96.1%), and were frequently combined with concomitant surgical procedures (47.9%). Early postoperative complications (first 30 days) were reported in 39.0%, with 71 being SSO. Of the 19.7% of patients with SSO, there were 31 who required procedural intervention. After a mean follow-up of 71.5 ± 20.5 months, hernia recurrence was documented in 34.9% of patients. Age and male gender were predictors of recurrence on multivariate analysis. CONCLUSION: To the best of our knowledge, this is the largest retrospective single institutional study evaluating PADCI to date. Hernias repaired with PADCI were frequently in patients undergoing concomitant operations. Reinforcement with PADCI may be considered a temporary closure, with a relatively high recurrence rate, especially among patients who are older, male, and undergo multiple explorations in a short perioperative period.


Asunto(s)
Hernia Ventral/cirugía , Herniorrafia , Dermis Acelular , Adulto , Anciano , Animales , Colágeno , Femenino , Herniorrafia/métodos , Xenoinjertos , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Mallas Quirúrgicas/efectos adversos , Porcinos , Resultado del Tratamiento
2.
Surg Endosc ; 31(4): 1573-1582, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-27495345

RESUMEN

BACKGROUND: Currently there is no consensus on management of ventral hernias encountered during bariatric surgery (BS). This study aims to evaluate the incidence and outcomes of concomitant ventral hernia repair (VHR) during BS at our institution. METHODS: Patients who had concomitant VHR during BS from 2004 to 2015 were identified. Data collected included baseline demographics, comorbidities, perioperative parameters, surgical approach and postoperative outcomes. RESULTS: A total of 159 patients underwent concomitant VHR during the study period at the time of BS. One hundred and one (64 %) patients were female; median age was 53 years (IQR 45.0-60.3) and median BMI was 48.2 kg/m2 (IQR 41.6-54.1). Comorbidities included: hypertension (n = 124, 78 %), type 2 diabetes (n = 103, 65 %), hyperlipidemia (n = 100, 63 %), obstructive sleep apnea (n = 98, 62 %) and reflux disease (n = 54, 34 %). Out of 159 patients, 41 patients (26 %) had a prior VHR. Out of 103 patients, 69 patients (67 %) had a previous abdominal surgery. Of the concomitant VHR, 144 (91 %) were completed laparoscopically, 12 (7 %) patients were converted to open surgery and 3 (2 %) patients underwent primary open procedures. Technique included primary suture closure in 115 (72 %) and mesh repair in 44. Early postoperative complications (<30 days) were reported in 16 (10 %) patients, with superficial wound infection (n = 9), bowel obstruction (n = 2), marginal ulcer (n = 2), DVT (n = 1) and pneumonia (n = 1). Hernia recurrence was reported in 3 patients (2 %) in the early post-op period and in 40 patients (25 %) as a late (>30 days) complication. Surgery for recurrent hernia was performed in 31/42 patients during follow-up. At 12-month follow-up, median BMI and % excess weight loss were 34.2 kg/m2 (IQR 29.5-40.9) and 59.6 % (IQR 44.9-74.8 %), respectively. CONCLUSION: Ventral hernia is a common finding in patients undergoing BS. Both primary suture repair and mesh repair result in acceptable results, both in terms of recurrence and perioperative complications.


Asunto(s)
Cirugía Bariátrica , Hernia Ventral/cirugía , Herniorrafia/métodos , Laparoscopía , Complicaciones Posoperatorias/cirugía , Adulto , Cirugía Bariátrica/métodos , Comorbilidad , Femenino , Humanos , Incidencia , Laparoscopía/métodos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/etiología , Recurrencia , Estudios Retrospectivos , Mallas Quirúrgicas , Suturas , Resultado del Tratamiento , Pérdida de Peso
4.
Surg Endosc ; 31(4): 1707-1712, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-27519595

RESUMEN

INTRODUCTION: Cholecystectomy is the preferred treatment for acute cholecystitis with percutaneous cholecystostomy (PC) considered an alternative therapy in severely debilitated patients. The aim of this study was to evaluate the efficacy and outcomes of PC at a tertiary referral center. METHODS: We retrospectively reviewed all patients that had undergone PC from 2000 to 2014. Data collected included baseline demographics, comorbidities, details of PC placement and management, and post-procedure outcomes. The Charlson comorbidity index (CCI) was calculated for all patients at the time of PC. RESULTS: Four hundred and twenty-four patients underwent PC placement from 2000 to 2014, and a total of 380 patients had long-term data available for review. Within this cohort, 223 (58.7 %) of the patients were male. The mean age at the time of PC placement was 65.3 ± 14.2 years of age, and the mean CCI was 3.2 ± 2.1 for all patients. One hundred and twenty-five (32.9 %) patients went on to have a cholecystectomy following PC placement. Comparison of patients who underwent PC followed by surgical intervention revealed that they were significantly younger (p = 0.0054) and had a lower CCI (p < 0.0001) compared to those who underwent PC alone. CONCLUSIONS: PC placement appears to be a viable, long-term alternative to cholecystectomy for the management of biliary disease in high-risk patients. Old and frail patients benefit the most, and in this cohort PC may be the definitive treatment.


Asunto(s)
Colecistitis Aguda/cirugía , Colecistostomía/instrumentación , Adulto , Anciano , Anciano de 80 o más Años , Colecistectomía , Colecistostomía/métodos , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Centros de Atención Terciaria , Resultado del Tratamiento
6.
Neurobiol Dis ; 40(3): 503-17, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20659558

RESUMEN

Mutations in the Leucine Rich Repeat Kinase 2 (LRRK2) gene, first described in 2004 have now emerged as the most important genetic finding in both autosomal dominant and sporadic Parkinson's disease (PD). While a formidable research effort has ensued since the initial gene discovery, little is known of either the normal or the pathological role of LRRK2. We have created lines of mice that express human wild-type (hWT) or G2019S Lrrk2 via bacterial artificial chromosome (BAC) transgenesis. In vivo analysis of the dopaminergic system revealed abnormal dopamine neurotransmission in both hWT and G2019S transgenic mice evidenced by a decrease in extra-cellular dopamine levels, which was detected without pharmacological manipulation. Immunopathological analysis revealed changes in localization and increased phosphorylation of microtubule binding protein tau in G2019S mice. Quantitative biochemical analysis confirmed the presence of differential phospho-tau species in G2019S mice but surprisingly, upon dephosphorylation the tau isoform banding pattern in G2019S mice remained altered. This suggests that other post-translational modifications of tau occur in G2019S mice. We hypothesize that Lrrk2 may impact on tau processing which subsequently leads to increased phosphorylation. Our models will be useful for further understanding of the mechanistic actions of LRRK2 and future therapeutic screening.


Asunto(s)
Encéfalo/metabolismo , Proteínas Serina-Treonina Quinasas/genética , Transmisión Sináptica/fisiología , Proteínas tau/metabolismo , Animales , Autorradiografía , Cromatografía Líquida de Alta Presión , Cromosomas Artificiales Bacterianos , Dopamina/metabolismo , Humanos , Immunoblotting , Hibridación in Situ , Proteína 2 Quinasa Serina-Treonina Rica en Repeticiones de Leucina , Masculino , Ratones , Ratones Transgénicos , Microdiálisis , Fosforilación , Procesamiento Proteico-Postraduccional , Receptores de Dopamina D1/metabolismo , Receptores de Dopamina D2/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
7.
Brain Res ; 1294: 22-8, 2009 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-19651107

RESUMEN

BACKGROUND: Neurotensin (NT) is a neuropeptide with antinociceptive effects that are mediated through NT receptors, of which there are three known subtypes (NTS1, NTS2, and NTS3). Morphine is a mu-opioid receptor agonist commonly used for pain treatment but is associated with side effects that can be serious. We hypothesize that selective NT receptor agonists may represent a novel class of analgesics and their use in conjunction with morphine will have synergistic properties which may reduce the dose of morphine administered and its side effects. METHODS: The antinociceptive activity of an NT agonist (NT69L) and morphine was studied in rats using the hot plate test to determine if there is synergism between the two drugs in reducing pain. The NTS2 receptor antagonist, levocabastine, was used to determine the receptor subtype involved in the analgesic effect of NT69L and morphine. RESULTS: The administration of both NT69L and morphine resulted in a dose-dependent analgesic effect. The isobolographic analysis demonstrated that the combination of sub-analgesic doses of NT69L and morphine was synergistic in the hot plate test. Pretreatment with the NTS2 receptor antagonist, levocabastine attenuated the antinociceptive effect of NT69L and the combined effect of NT69L and morphine in the hot plate test. CONCLUSION: The results support the hypothesis that the synergistic combination of NT69L and morphine would improve the pharmacological treatment of pain while minimizing specific adverse effects of each of the drugs at a higher dose. NTS2 is important for the antinociceptive effect of NT69L and morphine.


Asunto(s)
Analgésicos Opioides/farmacología , Analgésicos/farmacología , Morfina/farmacología , Neurotensina/análogos & derivados , Fragmentos de Péptidos/farmacología , Analgésicos/administración & dosificación , Analgésicos Opioides/administración & dosificación , Animales , Relación Dosis-Respuesta a Droga , Sinergismo Farmacológico , Calor , Masculino , Morfina/administración & dosificación , Neurotensina/administración & dosificación , Neurotensina/farmacología , Dolor/tratamiento farmacológico , Dimensión del Dolor , Fragmentos de Péptidos/administración & dosificación , Piperidinas/administración & dosificación , Piperidinas/farmacología , Ratas , Ratas Sprague-Dawley , Receptores de Neurotensina/antagonistas & inhibidores , Receptores de Neurotensina/metabolismo , Factores de Tiempo
8.
Brain Res ; 919(1): 1-11, 2001 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-11689157

RESUMEN

Neurotensin (NT) is a tridecapeptide neurotransmitter in the central nervous system. It has been implicated in the therapeutic effects of neuroleptics. Central activity of NT can only be demonstrated by direct injection into the brain, since it is readily degraded by peptidases in the periphery. We have developed many NT(8-13) analogs that are resistant to peptidase degradation and can cross the blood-brain barrier (BBB). In this study, we report on one of these analogs, NT77L. NT77L induced hypothermia (ED(50)=6.5 mg/kg, i.p.) but induced analgesia only at the highest dose examined (20 mg/kg, i.p.). Like the atypical neuroleptic clozapine, NT77L blocked the climbing behavior in rats induced by the dopamine agonist apomorphine (600 microg/kg) with an ED(50) of 5.6 mg/kg (i.p.), without affecting the licking and the sniffing behaviors. By itself NT77L did not cause catalepsy, but it moderately reversed haloperidol-induced catalepsy with an ED(50) of 6.0 mg/kg (i.p.). Haloperidol alone did not lower body temperature, but it potentiated the body temperature lowering effect of NT77L. In studies using in vivo microdialysis NT77L showed similar effects on dopamine turnover to those of clozapine, and significantly different from those of haloperidol in the striatum. In the prefrontal cortex, NT77L significantly increased serotonergic transmission as evidenced by increased 5-hydroxyindole acetic acid:5-hydroxytryptamine (5-HIAA:5-HT) ratio. Thus, NT77L selectively caused hypothermia, over antinociception, while exhibiting atypical neuroleptic-like effects.


Asunto(s)
Analgésicos/farmacología , Antipsicóticos/farmacología , Catalepsia/inducido químicamente , Hipotermia/inducido químicamente , Neurotensina/análogos & derivados , Neurotensina/farmacología , Animales , Barrera Hematoencefálica/efectos de los fármacos , Temperatura Corporal/efectos de los fármacos , Temperatura Corporal/fisiología , Catalepsia/metabolismo , Catalepsia/prevención & control , Cuerpo Estriado/efectos de los fármacos , Cuerpo Estriado/metabolismo , Dopamina/metabolismo , Relación Dosis-Respuesta a Droga , Haloperidol/administración & dosificación , Haloperidol/antagonistas & inhibidores , Hipotermia/metabolismo , Inyecciones Intraperitoneales , Masculino , Neurotensina/administración & dosificación , Fragmentos de Péptidos/administración & dosificación , Fragmentos de Péptidos/farmacología , Corteza Prefrontal/efectos de los fármacos , Corteza Prefrontal/metabolismo , Ratas , Ratas Sprague-Dawley , Serotonina/metabolismo
9.
Eur J Pharmacol ; 428(2): 227-33, 2001 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-11675040

RESUMEN

Parkinson's disease is a neuropathological disorder involving the degeneration of dopamine neurons in the substantia nigra, with the resultant loss of their terminals in the striatum. This dopamine loss causes most of the motor disturbances associated with the disease. One animal model of Parkinson's disease involves destruction of the nigrostriatal pathway with a neurotoxin (6-hydroxydopamine) injected into this pathway. In unilaterally lesioned animals, injection of D-amphetamine causes rotation towards the lesioned side, while injection of apomorphine acting upon supersensitive postsynaptic dopamine receptors causes rotation away from the lesioned side. In this study, we tested the effects of acute and subchronic injection of a neurotensin analog (NT69L) on the rotational behavior induced by D-amphetamine (5 mg/kg) or apomorphine (600 microg/kg) in unilaterally 6-hydroxydopamine lesioned rats. Pretreatment of animals with intraperitoneal injections of NT69L (1 mg/kg) resulted in a significant reduction of apomorphine-induced contralateral rotation and D-amphetamine-induced ipsilateral rotation in these lesioned rats with an ED(50) of 40 and 80 microg/kg, respectively. After three daily injections of NT69L, its effects on this rotational behavior were unchanged, suggesting that no tolerance develops to this effect of NT69L.


Asunto(s)
Antiparkinsonianos/farmacología , Neurotensina/análogos & derivados , Neurotensina/farmacología , Fragmentos de Péptidos/farmacología , Anfetamina/farmacología , Animales , Apomorfina/farmacología , Conducta Animal/efectos de los fármacos , Cuerpo Estriado/efectos de los fármacos , Cuerpo Estriado/metabolismo , Dopamina/metabolismo , Dopaminérgicos/farmacología , Relación Dosis-Respuesta a Droga , Actividad Motora/efectos de los fármacos , Oxidopamina , Enfermedad de Parkinson Secundaria/inducido químicamente , Enfermedad de Parkinson Secundaria/fisiopatología , Enfermedad de Parkinson Secundaria/prevención & control , Ratas , Ratas Sprague-Dawley
10.
Eur J Pharmacol ; 426(1-2): 73-6, 2001 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-11525773

RESUMEN

Neurotensin is a tridecapeptide that exhibits selective anatomic and neurochemical interactions with dopaminergic systems. Since dopaminergic neurotransmission underlies many of the behavioral properties of psychostimulants, and since neurotensin has been implicated in modulating dopaminergic neurotransmitter systems, we tested the effect of our novel neurotensin analog, NT69L (N-methyl-Arg(8),L-Lys(9),L-neo-Trp(11),tert-Leu(12)]neurotensin-(8-13)), on hyperactivity caused by cocaine and D-amphetamine. Previously, we showed that NT69L reduces body temperature, blocks apomorphine-induced climbing, and haloperidol-induced catalepsy. In this study, NT69L blocked the hyperactivity induced by both cocaine and D-amphetamine administered at three different doses each, when this peptide was injected intraperitoneally. These results provide further evidence for the involvement of the neurotensin system in some of the behavioral properties of psychostimulants and suggest that NT69L may find clinical application in patients who abuse this class of compounds.


Asunto(s)
Conducta Animal/efectos de los fármacos , Cocaína/farmacología , Dextroanfetamina/farmacología , Neurotensina/análogos & derivados , Neurotensina/farmacología , Fragmentos de Péptidos/farmacología , Animales , Relación Dosis-Respuesta a Droga , Masculino , Actividad Motora/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Factores de Tiempo
11.
Regul Pept ; 93(1-3): 125-36, 2000 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-11033059

RESUMEN

Neurotensin is an endogenous tridecapeptide neurotransmitter (pGlu-Leu-Tyr-Glu-Asn-Lys-Pro-Arg-Arg-Pro-Try-Ile-Leu-OH) that was discovered by Carraway and Leeman in bovine hypothalami in the early 1970s. Since then this peptide has been the subject of a multitude of articles detailing discoveries related to its activity, receptors, localization, synthesis, and interactions with other systems. This review article does not intend to summarize again all the history of this fascinating peptide and its receptors, since this has been done quite well by others. The reader will be directed to these other reviews, where appropriate. Instead, this review attempts to provide a summary of current knowledge about neurotensin, why it is an important peptide to study, and where the field is heading. Special emphasis is placed on the behavioral studies, particularly with reference to agonists, antagonists, and antisense studies, as well as, the interaction of neurotensin with other neurotransmitters.


Asunto(s)
Neurotensina/fisiología , Animales , Barrera Hematoencefálica , Bovinos , Dopamina/metabolismo , Humanos , Sistema Hipotálamo-Hipofisario/metabolismo , Hipotálamo , Neurotensina/análogos & derivados , Neurotensina/antagonistas & inhibidores , Neurotensina/metabolismo , Oligonucleótidos Antisentido , Sistema Hipófiso-Suprarrenal/metabolismo , Receptores de Neurotensina/genética , Esquizofrenia/metabolismo , Relación Estructura-Actividad
12.
Brain Res ; 865(1): 35-44, 2000 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-10814731

RESUMEN

Neurotensin decreases food intake in the rat when injected into the cerebral ventricles. We tested the effect of a novel neurotensin analog (NT69L), injected intra-peritoneally (i.p.), on weight gain and food intake in rats. Sprague-Dawley rats (270 g) were injected i. p. with either saline or NT69L at 0.001 or 0.010 mg/kg. In further experiments, larger rats at a more steady state on the growth curve (400 g) were injected with either saline or 0.010 or 1 mg/kg NT69L. Food intake, water consumption and body weight were recorded daily. Weight gain was significantly reduced in the smaller rats injected with 0.001 or 0.010 mg/kg, showing only a 8.5 and 9.0% increase in original weight, respectively, as compared to a 29% increase for the controls. The larger rats injected with 1 mg/kg, had a significant reduction in body weight with a 3.0% decrease in original body weight as compared to a 2.4% increase for the controls. Food intake was significantly reduced suggesting that the weight loss observed after injection of NT69L was attributable in part to a reduction in food intake. The genetically obese Zucker rats injected with NT69L (1 mg/kg) had a significant reduction in weight gain and food intake. NT69L significantly increased blood glucose and corticosterone levels and decreased TSH and T4 in Sprague-Dawley and Zucker rats, an effect that was only transitory. NT69L also caused a decrease in norepinephrine in both the hypothalamus and nucleus accumbens, and an increase in dopamine, 3,4-dihydroxyphenylacetic acid (DOPAC) and serotonin. In this study, NT69L exhibited a consistent and dramatic effect on body weight and food intake in Sprague-Dawley and obese Zucker rats, and enabled us to study the role that NT plays in weight control and the functional interactions of NT with brain amines, and metabolic and endocrinological parameters.


Asunto(s)
Peso Corporal/efectos de los fármacos , Ingestión de Alimentos/efectos de los fármacos , Neurotensina/análogos & derivados , Neurotensina/metabolismo , Fragmentos de Péptidos/farmacología , Animales , Glucemia/efectos de los fármacos , Peso Corporal/fisiología , Corticosterona/sangre , Dopamina/sangre , Relación Dosis-Respuesta a Droga , Vías de Administración de Medicamentos , Ingestión de Alimentos/fisiología , Masculino , Neurotensina/farmacología , Obesidad/tratamiento farmacológico , Obesidad/fisiopatología , Adenohipófisis/efectos de los fármacos , Adenohipófisis/metabolismo , Ratas , Ratas Sprague-Dawley , Serotonina/sangre , Tirotropina/sangre , Tirotropina/efectos de los fármacos , Tiroxina/sangre , Tiroxina/efectos de los fármacos , Factores de Tiempo
13.
Brain Res ; 856(1-2): 48-54, 2000 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-10677610

RESUMEN

Neurotensin (NT) is a neuropeptide neurotransmitter in the central nervous system. It has been implicated in the therapeutic and in the adverse effects of neuroleptics. Activity of NT in brain can only be shown by direct injection of the peptide into that organ. However, we have developed a novel analog of NT(8-13), NT69L, which is active upon intraperitoneal (i.p.) injection. Like atypical neuroleptics, NT69L blocked the climbing behavior in rats, but not the licking and sniffing behaviors of a high dose (600 microgram/kg) of the non-selective dopamine agonist apomorphine. Its blockade of climbing was very potent with an ED(50) (effective dose at 50% of maximum) of 16 microgram/kg. Both apomorphine and NT69L caused a long-lasting hypothermia, which was greater with the peptide but not synergistic in combination with apomorphine. The ED(50) of NT69L for hypothermia was 390 microgram/kg. NT69L (up to 5 mg/kg i.p.) did not produce catalepsy. However, when given before haloperidol, NT69L, but not clozapine, completely prevented catalepsy. When given after haloperidol, NT69L, but not clozapine, reversed haloperidol's cataleptic effects with an ED(50) of 260 microg/kg. There was no significant difference between the ED(50)s for hypothermia and anticataleptic effects of NT69L. However, the ED(50) for blocking the effects of apomorphine was significantly lower than the other two. These data suggest that NT69L may have neuroleptic properties in humans and may be useful in the treatment of extrapyramidal side effects caused by typical neuroleptics such as haloperidol.


Asunto(s)
Apomorfina/farmacología , Conducta Animal/efectos de los fármacos , Catalepsia/fisiopatología , Haloperidol/farmacología , Actividad Motora/efectos de los fármacos , Neurotensina/análogos & derivados , Fragmentos de Péptidos/farmacología , Animales , Apomorfina/antagonistas & inhibidores , Temperatura Corporal/efectos de los fármacos , Catalepsia/inducido químicamente , Clozapina/farmacología , Haloperidol/antagonistas & inhibidores , Inyecciones Intraperitoneales , Masculino , Ratones , Neurotensina/administración & dosificación , Neurotensina/farmacología , Fragmentos de Péptidos/administración & dosificación , Ratas , Ratas Sprague-Dawley , Factores de Tiempo
14.
Proc Natl Acad Sci U S A ; 96(12): 7053-8, 1999 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-10359837

RESUMEN

Intraperitoneal injection of an unmodified antisense peptide nucleic acid (PNA) complementary to mRNA of the rat neurotensin (NT) receptor (NTR1) was demonstrated by a gel shift assay to be present in brain, thus indicating that the PNA had in fact crossed the blood-brain barrier. An i.p. injection of this antisense PNA specifically inhibited the hypothermic and antinociceptive activities of NT microinjected into brain. These results were associated with a reduction in binding sites for NT both in brain and the small intestine. Additionally, the sense-NTR1 PNA, targeted to DNA, microinjected directly into the brain specifically reduced mRNA levels by 50% and caused a loss of response to NT. To demonstrate the specificity of changes in behavioral, binding, and mRNA studies, animals treated with NTR1 PNA were tested for behavioral responses to morphine and their mu receptor levels were determined. Both were found to be unaffected in these NTR1 PNA-treated animals. The effects of both the antisense and sense PNAs were completely reversible. This work provides evidence that any antisense strategy targeted to brain proteins can work through i. p. delivery by crossing the normal blood-brain barrier. Equally important was that an antigene strategy, the sense PNA, was shown in vivo to be a potentially effective therapeutic treatment.


Asunto(s)
Elementos sin Sentido (Genética)/administración & dosificación , Regulación de la Expresión Génica/efectos de los fármacos , Ácidos Nucleicos de Péptidos/administración & dosificación , Receptores de Neurotensina/efectos de los fármacos , Receptores de Neurotensina/genética , Animales , Transporte Biológico , Barrera Hematoencefálica , Sistemas de Liberación de Medicamentos , Inyecciones Intraperitoneales , Masculino , Ratas , Ratas Sprague-Dawley
15.
J Chromatogr B Biomed Sci Appl ; 692(1): 187-98, 1997 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-9187399

RESUMEN

A capillary electrophoresis (CE) and a solid-phase extraction method was developed for the determination of flunixin in equine urine and serum. The suitable CE run conditions were described. The factors affecting flunixin recovery rates were investigated and optimum solid-phase extraction conditions for flunixin in equine urine and serum were established. Limits of detection and quantitation were 3.4 and 5.6 ng/ml for serum and 16.9 and 33.1 ng/ml for urine, respectively. The recoveries exceeded 96% for urine and 79% for serum. Urine samples from race horses and urine and serum samples from a mare administrated with flunixin were analyzed with this procedure.


Asunto(s)
Antiinflamatorios no Esteroideos/sangre , Antiinflamatorios no Esteroideos/orina , Clonixina/análogos & derivados , Animales , Antiinflamatorios no Esteroideos/farmacocinética , Clonixina/sangre , Clonixina/farmacocinética , Clonixina/orina , Doping en los Deportes , Electroforesis Capilar , Caballos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
16.
Am J Vet Res ; 57(2): 182-6, 1996 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8633805

RESUMEN

OBJECTIVE: To develop a simple and sensitive ELISA for detection of dexamethasone in horse serum and urine. SAMPLE POPULATION: Blood and urine samples from 3 thoroughbred mares. PROCEDURE: A dexamethasone oxime was prepared and conjugated to hemocyanin, bovine serum albumin and to horseradish peroxidase. One- and two-step double-antibody ELISA methods, as well as a radioimmunoassay method, were performed. The one-step ELISA was used to test urine from 3 Thoroughbred mares injected with 5 mg of dexamethasone, IV. RESULTS: The ELISA could detect dexamethasone in the range of 0.01 to 50 ng/ml, with intra- and interassay variations of 8.92 and 9.42%, respectively. Serum dexamethasone concentration reached a peak of 20 to 35 ng/ml 15 minutes after steroid administration and decreased to 1 ng/ml in 2.5 hours. Urine dexamethasone concentration 18 to 50 ng/ml 1 to 2 hours after drug administration and decreased to 1 ng/ml at 10 hours. CONCLUSION: The developed assay is sensitive as well as simple for detecting dexamethasone in horse serum and urine, and is comparable to radioimmunoassay. CLINICAL RELEVANCE: This method can be useful for screening samples from racehorses, because it is sensitive and does not require sample preparation or sophisticated equipment.


Asunto(s)
Dexametasona/sangre , Dexametasona/orina , Ensayo de Inmunoadsorción Enzimática/veterinaria , Caballos/metabolismo , Radioinmunoensayo/veterinaria , Animales , Reacciones Cruzadas , Dexametasona/administración & dosificación , Dexametasona/farmacocinética , Ensayo de Inmunoadsorción Enzimática/métodos , Femenino , Inyecciones Intravenosas/veterinaria , Modelos Lineales , Conejos , Radioinmunoensayo/métodos , Estándares de Referencia
17.
J Capillary Electrophor ; 3(1): 43-9, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-9384764

RESUMEN

A capillary electrophoresis technique was developed for the separation of synthetic glucocorticoids and the determination of dexamethasone and flumethasone in horse urine. Pretreatment of the sample using a dexamethasone affinity column resulted in low background that enabled the authors to detect levels as low as 1.1 ng/mL and 2.7 ng/mL for dexamethasone and flumethasone in horse urine, respectively. The developed method was used to detect dexamethasone in horse urine samples after the injection of a therapeutic dose of dexamethasone for up to 12 hr postinjection. The optimum conditions for capillary electrophoresis and dexamethasone elution from the affinity column are described.


Asunto(s)
Dexametasona/orina , Flumetasona/orina , Glucocorticoides/orina , Animales , Anticuerpos , Acción Capilar , Cromatografía/instrumentación , Cromatografía/métodos , Cromatografía de Afinidad/instrumentación , Cromatografía de Afinidad/métodos , Cromatografía Líquida de Alta Presión , Dexametasona/aislamiento & purificación , Dexametasona/farmacocinética , Electroforesis Capilar/instrumentación , Electroforesis Capilar/métodos , Femenino , Flumetasona/aislamiento & purificación , Glucocorticoides/aislamiento & purificación , Caballos , Inmunoglobulina G , Micelas , Conejos , Radioinmunoensayo , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
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