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1.
Lupus ; 27(5): 853-857, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28857716

RESUMEN

Introduction Chronic cutaneous lupus erythematosus (CCLE) usually presents as characteristic erythematous patches and infiltrated coin-shaped plaques. However, there are some atypical clinical variants that may mimic other dermatological conditions. Haroon et al. reported in 1972 an unusual presentation of CCLE with hypertrophic follicular scars seen in acne vulgaris. Acneiform presentation is one of the most rarely reported and one of the most confusing, as it resembles a very common inflammatory skin disease. A brief review of the literature using PubMed found only nine other reports. Case report A 32-year-old woman presented with two-year pruritic infiltrated acneiform and comedonal eruption on the right chin treated as acne with isotretinoin without improvement. On examination the patient presented with erythematous-infiltrated plaque, papules, open comedones, pitting scars and hypopigmented atrophic scars on the right chin area and scalp hair loss. An incisional skin biopsy on the chin and scalp lesions was performed and the anatomopathological and immunofluorescence exam showed findings that are consistent with CCLE. Additional tests ruled out systemic involvement. The patient was treated with prednisone and chloroquine diphosphate with great improvement. After four years the lesion is stable, with some scarring. Discussion In a literature review we found nine other cases of acneiform presentation of lupus erythematosus: Three cases were systemic lupus erythematosus (SLE) and seven others were diagnosed as CCLE (including our patient). All three patients who had SLE tested positive for antinuclear antibodies (ANA), and only one patient with CCLE, had a low titer of positive ANA (1:80). Ages varied from 24 to 60 years old, with a median of 32 years old, the same as our patient's age and consistent with the literature. Seven were females and three were males, with a ratio of 2.3:1. Most cases, such as our patient, showed acneiform lesions mainly on the face, a common site of typical CCLE. The present case and literature review illustrates the need to expand the differential diagnosis of atypical acneiform and comedonal lesions. CCLE should be considered especially in a localized lesion, which can be itchy and does not improve with conventional treatment for acne vulgaris.


Asunto(s)
Erupciones Acneiformes/diagnóstico , Lupus Eritematoso Cutáneo/diagnóstico , Piel/patología , Erupciones Acneiformes/patología , Adulto , Antiinflamatorios no Esteroideos/uso terapéutico , Biopsia , Cloroquina/análogos & derivados , Cloroquina/uso terapéutico , Enfermedad Crónica , Errores Diagnósticos , Quimioterapia Combinada , Femenino , Técnica del Anticuerpo Fluorescente , Glucocorticoides/uso terapéutico , Humanos , Lupus Eritematoso Cutáneo/tratamiento farmacológico , Lupus Eritematoso Cutáneo/patología , Valor Predictivo de las Pruebas , Prednisona/uso terapéutico , Piel/efectos de los fármacos , Resultado del Tratamiento
2.
Nutr Metab Cardiovasc Dis ; 28(4): 393-401, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29422298

RESUMEN

BACKGROUND AND AIMS: An increase in plasma branched-chain amino acids is associated with a higher risk of developing type 2 diabetes and cardiovascular diseases. However, little is known about the basal plasma amino acid concentrations in young adults. Our aim was to determine the plasma amino acid profiles of young adults and to evaluate how these profiles were modified by sex, body mass index (BMI) and insulin resistance (IR). METHODS AND RESULTS: We performed a transversal study with 608 Mexican young adults aged 19.9 ± 2.4 years who were applicants to the Universidad Autónoma de San Luis Potosí. The subjects underwent a physical examination and provided a clinical history and a blood sample for biochemical, hormonal and amino acid analyses. The women had higher levels of arginine, aspartate and serine and lower levels of α-aminoadipic acid, cysteine, isoleucine, leucine, methionine, proline, tryptophan, tyrosine, urea and valine than the men. The obese subjects had higher levels of alanine, aspartate, cysteine, ornithine, phenylalanine, proline and tyrosine and lower levels of glycine, ornithine and serine than the normal weight subjects. Subjects with IR (defined as HOMA > 2.5) had higher levels of arginine, alanine, aspartate, isoleucine, leucine, phenylalanine, proline, tyrosine, taurine and valine than the subjects without IR. Furthermore, we identified two main groups in the subjects with obesity and/or IR; one group was composed of amino acids that positively correlated with the clinical, biochemical and hormonal parameters, whereas the second group exhibited negative correlations. CONCLUSION: This study demonstrates that young adults with obesity or IR have altered amino acid profiles characterized by an increase in alanine, aspartate, proline and tyrosine and a decrease in glycine.


Asunto(s)
Aminoácidos/sangre , Índice de Masa Corporal , Resistencia a la Insulina , Obesidad Infantil/sangre , Adolescente , Fenómenos Fisiológicos Nutricionales de los Adolescentes , Factores de Edad , Biomarcadores/sangre , Estudios Transversales , Femenino , Humanos , Masculino , México/epidemiología , Estado Nutricional , Obesidad Infantil/diagnóstico , Obesidad Infantil/epidemiología , Obesidad Infantil/fisiopatología , Prevalencia , Factores de Riesgo , Factores Sexuales , Adulto Joven
3.
Rev Gastroenterol Mex ; 82(4): 301-308, 2017.
Artículo en Inglés, Español | MEDLINE | ID: mdl-28363494

RESUMEN

INTRODUCTION AND AIMS: Clostridium difficile infection is the main cause of hospital-acquired diarrhea, and the clinical and endoscopic findings in those patients have been studied very little in Mexico. The aim of the present study was to describe those findings. MATERIALS AND METHODS: A prospective cohort study was conducted that included patients with hospital-acquired diarrhea associated with Clostridium difficile diagnosed through polymerase chain reaction. The hypervirulent NAP027 strain was also determined. The clinical and endoscopic findings in the study patients, as well as the variables associated with severity, were analyzed. RESULTS: Of the 127 patients with hospital-acquired diarrhea, 97 were excluded from the study due to lack of colonoscopy. The remaining 39 study patients had a mean age of 48 years, and their most common signs/symptoms were abdominal pain (49%), mucus in stools (41%), and blood in stools (10%). The most common alterations in the laboratory results were leukocytosis in 49%, fecal leukocytes (61%), and hypoalbuminemia (67%). The main risk factor was antibiotic use in 62%, and ceftriaxone was the most widely used. The hypervirulent strain was present in 54% of the cases. Endoscopic abnormalities were found in 87% of the patients. Thirty-eight percent presented with pseudomembranous colitis, with lesions in the left colon in 53%, and in the right colon in 13%. No association was found between proton-pump inhibitor use and Clostridium difficile-associated diarrhea. There was a significant association between hypoalbuminemia (< 3.3g/dL) and a greater risk for severe colitis, with a RR of 8.2 (p=0.008). CONCLUSIONS: Pseudomembranous colitis lesions associated with the hypervirulent Clostridium difficile strain were predominant in the left colon. Hypoalbuminemia was a significant severity predictor.


Asunto(s)
Clostridioides difficile , Infecciones por Clostridium/diagnóstico , Infección Hospitalaria/diagnóstico , Diarrea/microbiología , Adulto , Anciano , Clostridioides difficile/clasificación , Infecciones por Clostridium/etiología , Infecciones por Clostridium/microbiología , Infección Hospitalaria/etiología , Infección Hospitalaria/microbiología , Diarrea/diagnóstico por imagen , Endoscopía Gastrointestinal , Enterocolitis Seudomembranosa/diagnóstico , Enterocolitis Seudomembranosa/etiología , Enterocolitis Seudomembranosa/microbiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Factores de Riesgo
7.
Sci Rep ; 10(1): 15229, 2020 09 17.
Artículo en Inglés | MEDLINE | ID: mdl-32943651

RESUMEN

Pomegranate seed oil (PSO) is mainly composed of punicic acid (PA), a polyunsaturated fatty acid also known as omega-5 (ω-5), a potent antioxidant associated with a variety of metabolic and cellular beneficial effects. However, the potential benefits of a nanoemulsified version of ω-5 (PSOn) have not been evaluated in a pathological liver condition. Here, we examined whether PSOn had beneficial effects on C57BL/6N mice fed a high-fat diet (HFD), specifically on hepatic steatosis. We observed that PSOn supplementation decreased body weight and body fat mass in control mice, whereas glucose intolerance, insulin resistance, energy expenditure, and hepatic steatosis were improved in both control mice and in mice fed a HFD. Interestingly, PSOn increased fatty acid oxidation in primary hepatocytes and antioxidant gene expression. Altogether, our data indicate that PSOn effectively reduces some of the HFD-derived metabolic syndrome indicators by means of an increase in fatty acid oxidation within hepatocytes.


Asunto(s)
Ácidos Grasos Insaturados/administración & dosificación , Ácidos Linolénicos/administración & dosificación , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Animales , Antioxidantes/administración & dosificación , Dieta Alta en Grasa/efectos adversos , Emulsiones , Metabolismo Energético/efectos de los fármacos , Ácidos Grasos/metabolismo , Intolerancia a la Glucosa/tratamiento farmacológico , Intolerancia a la Glucosa/metabolismo , Hepatocitos/metabolismo , Resistencia a la Insulina , Masculino , Ratones , Ratones Endogámicos C57BL , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/patología , Oxidación-Reducción , Fitoterapia , Aceites de Plantas/administración & dosificación , Granada (Fruta)/química
8.
Reprod Biomed Online ; 19(2): 228-37, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19712560

RESUMEN

Chromosome abnormalities are common in oocytes derived from patients undergoing IVF treatment. The proportion of oocytes displaying aneuploidy is closely related to maternal age and may exceed 60% in patients over 40 years old. However, little information currently exists concerning the incidence of such anomalies in oocytes derived from young fertile women. A total of 121 metaphase II oocytes and their corresponding first polar bodies (PB) were analysed with the use of a comprehensive cytogenetic method, comparative genomic hybridization (CGH). The oocytes were donated from 13 young women (average age 22 years) without any known fertility problems. All oocytes were mature at the time of retrieval and were unexposed to spermatozoa. A low aneuploidy rate (3%) was detected. These results clearly indicate that meiosis I segregation errors are not frequent in oocytes of young fertile women. The higher aneuploidy rates reported in embryos derived from donor oocytes could be due to aggressive hormonal stimulation, in combination with male factors. However a definite contributing factor remains to be elucidated. The data obtained during this study also illustrate that CGH accurately and efficiently detects aneuploidy, confirming that it is suitable for application in a clinical setting for the assessment of oocytes, via PB analysis.


Asunto(s)
Oocitos , Donantes de Tejidos , Adulto , Aneuploidia , Femenino , Humanos , Hibridación de Ácido Nucleico
9.
BMC Public Health ; 8: 219, 2008 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-18577205

RESUMEN

BACKGROUND: The criterion for dementia implicit in DSM-IV is widely used in research but not fully operationalised. The 10/66 Dementia Research Group sought to do this using assessments from their one phase dementia diagnostic research interview, and to validate the resulting algorithm in a population-based study in Cuba. METHODS: The criterion was operationalised as a computerised algorithm, applying clinical principles, based upon the 10/66 cognitive tests, clinical interview and informant reports; the Community Screening Instrument for Dementia, the CERAD 10 word list learning and animal naming tests, the Geriatric Mental State, and the History and Aetiology Schedule - Dementia Diagnosis and Subtype. This was validated in Cuba against a local clinician DSM-IV diagnosis and the 10/66 dementia diagnosis (originally calibrated probabilistically against clinician DSM-IV diagnoses in the 10/66 pilot study). RESULTS: The DSM-IV sub-criteria were plausibly distributed among clinically diagnosed dementia cases and controls. The clinician diagnoses agreed better with 10/66 dementia diagnosis than with the more conservative computerized DSM-IV algorithm. The DSM-IV algorithm was particularly likely to miss less severe dementia cases. Those with a 10/66 dementia diagnosis who did not meet the DSM-IV criterion were less cognitively and functionally impaired compared with the DSMIV confirmed cases, but still grossly impaired compared with those free of dementia. CONCLUSION: The DSM-IV criterion, strictly applied, defines a narrow category of unambiguous dementia characterized by marked impairment. It may be specific but incompletely sensitive to clinically relevant cases. The 10/66 dementia diagnosis defines a broader category that may be more sensitive, identifying genuine cases beyond those defined by our DSM-IV algorithm, with relevance to the estimation of the population burden of this disorder.


Asunto(s)
Algoritmos , Demencia/diagnóstico , Diagnóstico por Computador , Manual Diagnóstico y Estadístico de los Trastornos Mentales , Anciano , Estudios de Casos y Controles , Áreas de Influencia de Salud , Cognición , Servicios Comunitarios de Salud Mental , Cuba , Femenino , Evaluación Geriátrica , Humanos , Entrevistas como Asunto , Masculino , Pruebas Psicológicas
10.
Genet Mol Res ; 7(1): 7-15, 2008 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-18273814

RESUMEN

The human orosomucoid 1 gene (ORM1) codes an alpha-1-acid glycoprotein that has been classified as an acute-phase reactive protein, and a major drug-binding serum component, as well as an immunomodulatory protein with genetic polymorphisms. Evaluation of ORM variation through isoelectric focusing and immunobloting has revealed a world-wide distribution of the ORM1 F and ORM1 S alleles. We evaluated and examined the genetic characteristics of two Mexican populations that have different anthropological and cultural antecedents, examining two ORM1 genotypes (exon 1 - A/G (Gln20Arg) and exon 5 G/A (Val156Met)) in 145 individuals, using nested polymerase chain reaction, sequencing, and restricted fragment length polymorphism. Mexican Mestizos had higher frequencies of the exon 1 A allele (P = 0.020) and AA genotype (P = 0.018) and lower frequency of the G allele (P = 0.020) when compared to Teenek Amerindians. When we examined exon 5 G/A (Val156Met) polymorphisms, we found significantly higher frequencies of the G allele (P = 0.0007) and the GG genotype (P = 0.0003) in the Mexican Mestizo population. The Teenek population had a significantly higher frequency of the A allele than has been reported for Chinese and African (P < 0.05) populations, and the G/A genotype was more frequently found in this Mexican population than in Chinese, African and European populations (P < 0.05).


Asunto(s)
Exones/genética , Genética de Población , Indígenas Norteamericanos/genética , Orosomucoide/genética , Polimorfismo Genético , Alelos , ADN/genética , ADN/aislamiento & purificación , Frecuencia de los Genes , Variación Genética , Humanos , México , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Análisis de Secuencia de ADN , Estadística como Asunto
11.
New Microbes New Infect ; 18: 50-53, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28626584

RESUMEN

Invasive amoebiasis is a life-threatening infection requiring immediate detection and treatment. However, diagnosis is challenging because conventional methods such as light microscopy and serology are unreliable. Molecular techniques are therefore considered the new diagnostic reference standard, but most of the developed assays are research tools and not widely available. Recently commercial multiplex PCR panels have been introduced which permit the simultaneous detection of multiple enteric pathogens including Entamoeba histolytica in stool samples. Our report demonstrates for the first time that these new assays might also serve as a rapid tool to diagnose amoebic liver abscess in patients with cystic focal liver lesions.

12.
Rev Neurol ; 41(3): 155-8, 2005.
Artículo en Español | MEDLINE | ID: mdl-16047299

RESUMEN

INTRODUCTION: The late onset epilepsy is defined like that start in the adult life after the 25 years old. The diagnostic assessment of the late onset epilepsy forces to discard, in the absence of the principal causes like stroke, tumors and trauma to the metabolic cause like plausible. The persistent hypocalcemia, apart of its acute repercussions, produces severe neurologic consequences. CASE REPORT: Feminine patient of 61 years old, that assists with a tonic clonic generalized seizure and tetany facts in the physical exam (Chvostek and Trousseau), round facies, obesity and metacarpals abnormalities. The hypocalcemia, hyperphosphatemia and resistance to parathyroid hormone (with normal levels of cAM in urine after stimulation with PTH) triad outline the pseudohypoparathyroidism. CONCLUSIONS: Consider by the clinical history, biochemical results and clinical findings consistent with Albright hereditary osteodystrophy a pseudohypoparathyroidism type Ia in this patient; is the more common form of this disorders and have a dominant pattern of inheritance, is produced by a detectable mutation in the stimulatory Gs alpha, one protein of the adenylil cyclase complex (GNAS1) that is traduced in a inefficacy of the PTH renal receptor. The main goals of treatment are reduce and maintain the serum calcium and PTH levels, respectively.


Asunto(s)
Epilepsia/etiología , Seudohipoparatiroidismo/complicaciones , Seudohipoparatiroidismo/diagnóstico , Adulto , Calcinosis/etiología , Calcinosis/patología , Epilepsia/fisiopatología , Femenino , Mano/patología , Humanos , Hipocalcemia/complicaciones , Hipocalcemia/etiología , Hipocalcemia/patología , Hipocalcemia/fisiopatología , Persona de Mediana Edad , Hormona Paratiroidea/análogos & derivados , Hormona Paratiroidea/metabolismo , Seudohipoparatiroidismo/patología , Seudohipoparatiroidismo/fisiopatología
13.
AIDS ; 14(13): 1973-8, 2000 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-10997402

RESUMEN

OBJECTIVES: To compare the efficacy and safety of two-times-daily versus three-times-daily indinavir in combination with zidovudine and lamivudine. DESIGN: Two multicenter, open-label, randomized 24-week studies. METHODS: Adults HIV-1 infection, HIV-1 RNA greater than 10000 copies/ml, and no prior lamivudine or protease inhibitor therapy were eligible. In a pilot study (Study A), patients received indinavir at 800 mg every 8 h, 1000 mg every 12 h, or 1200 mg every 12 h. In a subsequent study (Study B), patients received indinavir at 800 mg every 8 h or 1200 mg every 12 h. All subjects received zidovudine (300 mg) and lamivudine (150 mg) every 12 h. An intent-to-treat analysis was used. RESULTS: In Study A, which enrolled 88 patients, neither HIV-1 RNA nor CD4 cell responses differed significantly between treatment groups at 24 weeks when corrected for multiple comparisons. Study B enrolled 433 patients, but was prematurely discontinued when interim analysis suggested greater efficacy of three-times-daily indinavir. Of the first 87 patients reaching week 24, HIV-1 RNA was less than 400 copies/ml in 91% receiving three-times-daily versus 64% receiving two-times-daily indinavir (P < 0.01). CONCLUSION: Three-times-daily indinavir appears more efficacious than two-times-daily dosing when administered with zidovudine and lamivudine. Two-times-daily indinavir dosing should only be considered in situations characterized by favorable pharmacokinetic drug-drug interactions.


Asunto(s)
Fármacos Anti-VIH/uso terapéutico , Infecciones por VIH/tratamiento farmacológico , Indinavir/administración & dosificación , Lamivudine/uso terapéutico , Inhibidores de la Transcriptasa Inversa/uso terapéutico , Zidovudina/uso terapéutico , Adulto , Fármacos Anti-VIH/efectos adversos , Terapia Antirretroviral Altamente Activa , Recuento de Linfocito CD4 , Esquema de Medicación , Infecciones por VIH/virología , VIH-1/aislamiento & purificación , VIH-1/fisiología , Humanos , Indinavir/efectos adversos , Indinavir/uso terapéutico , Lamivudine/efectos adversos , Proyectos Piloto , ARN Viral/sangre , Inhibidores de la Transcriptasa Inversa/efectos adversos , Resultado del Tratamiento , Carga Viral , Zidovudina/efectos adversos
14.
Am J Med ; 113(4): 294-9, 2002 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12361815

RESUMEN

BACKGROUND: Candida esophagitis remains an important cause of morbidity in patients with advanced human immunodeficiency virus (HIV) infection. Fluconazole is widely regarded as the treatment of choice for this condition. METHODS: The efficacy and safety of caspofungin were compared with fluconazole in adult patients with Candida esophagitis in a double-blind randomized trial. Eligible patients had symptoms compatible with esophagitis, endoscopic demonstration of mucosal plaques, and microscopic demonstration of Candida from the esophageal lesions. Patients were randomly assigned to receive caspofungin (50 mg) or fluconazole (200 mg) intravenously once daily for 7 to 21 days. The primary endpoint was the combined response of symptom resolution and significant endoscopic improvement 5 to 7 days after discontinuation of treatment. Data were analyzed with a modified intention-to-treat analysis, which excluded 2 ineligible patients. RESULTS: Most patients (154/177; 87%) had HIV infection, with a median CD4 count of 30 cells/mm(3). Candida albicans was the predominant isolate. Favorable response rates were achieved in 66 (81%) of the 81 patients in the caspofungin arm and in 80 (85%) of the 94 patients in the fluconazole arm (difference = -4%; 95% confidence interval: -15% to +8%). Symptoms had resolved in >50% of patients in both groups by the fifth day of treatment. No patient in the caspofungin group developed a serious drug-related adverse event; therapy was only discontinued in 1 patient (receiving fluconazole) due to a drug-related adverse experience. Four weeks after stopping study drug, symptoms had recurred in 18 (28%) of 64 patients given caspofungin and in 12 (17%) of 72 patients given fluconazole (P = 0.19). CONCLUSIONS: In this study, caspofungin appeared to be as efficacious and generally as well tolerated as fluconazole in patients with advanced HIV infection and documented Candida esophagitis.


Asunto(s)
Infecciones Oportunistas Relacionadas con el SIDA/tratamiento farmacológico , Antibacterianos/uso terapéutico , Antifúngicos/uso terapéutico , Candidiasis Bucal/tratamiento farmacológico , Esofagitis/tratamiento farmacológico , Fluconazol/uso terapéutico , Péptidos Cíclicos , Péptidos , Infecciones Oportunistas Relacionadas con el SIDA/patología , Adolescente , Adulto , Anciano , Antibacterianos/administración & dosificación , Antifúngicos/administración & dosificación , Candidiasis Bucal/patología , Caspofungina , Chile , Método Doble Ciego , Esquema de Medicación , Equinocandinas , Esofagitis/patología , Esofagoscopía , Femenino , Fluconazol/administración & dosificación , Guatemala , Humanos , Infusiones Intravenosas , Lipopéptidos , Masculino , Persona de Mediana Edad , Pennsylvania , Perú , Resultado del Tratamiento
15.
Neuropharmacology ; 39(13): 2543-60, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11044726

RESUMEN

HEK293 cells were stably transfected with the cDNAs encoding full-length human neuronal nicotinic acetylcholine receptor (nAChR) subunit combinations alpha3beta2 or alpha4beta2. [(3)H]-(+/-)Epibatidine ([(3)H]-(+/-)EPI) bound to membranes from A3B2 (alpha3beta2) and A4B2.2 (alpha4beta2) cells with K(d) values of 7.5 and 33.4 pM and B(max) values of 497 and 1564 fmol/mg protein, respectively. Concentration-dependent increases in intracellular free Ca(2+) concentration were elicited by nAChR agonists with a rank order of potency of EPI>1,1-dimethyl-4-phenylpiperazinium (DMPP)>nicotine (NIC)=suberyldicholine (SUB)>cytisine (CYT)=acetylcholine (ACh) for A3B2 cells and EPI>CYT=SUB=NIC=DMPP>ACh for A4B2.2 cells. Antagonists of nAChRs blocked NIC-induced responses with a rank order of potency of d-tubocurarine (d-Tubo)=mecamylamine (MEC)>dihydro-beta-erythroidine (DHbetaE) in A3B2 cells and MEC=DHbetaE>d-Tubo in A4B2.2 cells. Whole-cell patch clamp recordings indicate that the decay rate of macroscopic ACh-induced currents is faster in A3B2 than in A4B2.2 cells and that A3B2 cells are less sensitive to ACh than A4B2.2 cells. ACh currents elicited in alpha3beta2 and alpha4beta2 human nAChRs are maximally potentiated at 20 and 2 mM external Ca(2+), respectively. Our results indicate that stably expressed alpha3beta2 and alpha4beta2 human nAChRs are pharmacologically and functionally distinct.


Asunto(s)
Receptores Nicotínicos/metabolismo , Northern Blotting , Western Blotting , Calcio/metabolismo , Línea Celular , Estimulación Eléctrica , Electrofisiología , Humanos , Riñón/metabolismo , Ligandos , Membranas/efectos de los fármacos , Membranas/metabolismo , Agonistas Nicotínicos/farmacología , Técnicas de Placa-Clamp , ARN/biosíntesis , ARN/aislamiento & purificación , Ensayo de Unión Radioligante , Receptores Nicotínicos/efectos de los fármacos , Receptores Nicotínicos/genética , Proteínas Recombinantes/química
16.
J Mol Neurosci ; 7(3): 217-28, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8906617

RESUMEN

cDNA clones encoding human neuronal nicotinic acetylcholine receptor alpha 2, alpha 3, alpha 4, alpha 5, alpha 6, alpha 7, beta 2, beta 3, and beta 4 subunits were isolated from brainstem, hippocampus, prefrontal cortex, substantia nigra, thalamus, and IMR32 libraries. Human alpha 2 and alpha 6 and full-length beta 3 and beta 4 clones have not been previously reported. Deduced amino acid sequences of the alpha 2, alpha 6, beta 3, and beta 4 predicted mature peptides are 503 residues (56.9 kDa), 464 residues (53.7 kDa), 440 residues (50.8 kDa), and 477 residues (54.1 kDa), respectively. These sequences show 84 (alpha 2), 87 (alpha 6), 89 (beta 3), and 84% (beta 4) identity to the corresponding rat sequences. The amino termini of the human alpha 2 and beta 3 mature peptides contain 23 and six additional residues, respectively, compared to those of rat alpha 2 and beta 3. Recombinant receptors were expressed in Xenopus laevis oocytes injected with in vitro transcripts encoding either alpha 7 alone or alpha 2, alpha 3, or alpha 4 in pairwise combination with beta 2 or beta 4. Inward currents were elicited by the application of acetylcholine (1-100 microM) and other agonists; these responses were blocked 65-97% by application of 10 microM d-tubocurare, confirming functional expression of human nicotinic receptors.


Asunto(s)
Neuronas/metabolismo , Receptores Nicotínicos/biosíntesis , Receptores Nicotínicos/química , Acetilcolina/farmacología , Secuencia de Aminoácidos , Animales , Clonación Molecular , ADN Complementario , Femenino , Biblioteca de Genes , Humanos , Sustancias Macromoleculares , Potenciales de la Membrana/efectos de los fármacos , Datos de Secuencia Molecular , Oocitos/fisiología , Ratas , Receptores Nicotínicos/fisiología , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/química , Homología de Secuencia de Aminoácido , Xenopus laevis
17.
Brain Res ; 379(2): 300-6, 1986 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-2874869

RESUMEN

The excitability of the dopamine-containing terminal field in the striatum (St) following frontal cortex (FC) stimulation was investigated in halothane-anesthetized rats. Either glutamic acid (GLU, 6.2 mM) or square pulses (a train of 25 pulses, 500-800 microA/0.3 ms: 1 Hz/20 s) were used to stimulate FC. To stimulate St monophasic square wave pulses (10-4000 microA/0.5 ms/1 Hz) were delivered. Excitability was measured by determining the threshold for antidromic activation of substantia nigra cells. Threshold was defined as the minimum current required for antidromic invasion of the cell on 100% of non-collision trials. The mean threshold current was 1029 +/- 167 microA. Following FC stimulation a significant decrease (30%) in excitability was observed in most cases (80%). No correlation between firing rate and threshold fluctuations was observed. It is concluded that FC activity decreases the excitability of the dopaminergic nigrostriatal terminal field. Whether this is a direct or an indirect effect is discussed.


Asunto(s)
Cuerpo Estriado/fisiología , Dopamina/fisiología , Lóbulo Frontal/fisiología , Terminaciones Nerviosas/fisiología , Animales , Estimulación Eléctrica , Potenciales Evocados/efectos de los fármacos , Glutamatos/farmacología , Ácido Glutámico , Masculino , Vías Nerviosas/fisiología , Ratas , Ratas Endogámicas , Tiempo de Reacción/efectos de los fármacos
18.
Brain Res ; 574(1-2): 85-92, 1992 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-1379110

RESUMEN

Activation of cAMP-dependent protein kinase (kinase A) has recently been shown to enhance responses evoked by stimulation of alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionate (AMPA) receptors in cultured hippocampal pyramidal neurons. Here we report results of experiments designed to determine if activation of the cAMP cascade potentiates synaptic strength in field CA1 of rat hippocampal slices. We find that bath application of the direct adenylate cyclase activator forskolin (50 microM) enhances the field excitatory postsynaptic potential (EPSP) slope and population spike amplitude evoked by stimulation of Schaffer/commissural afferents. This effect is potentiated by the phosphodiesterase inhibitor and adenosine receptor antagonist 3-isobutyl-1-methylxanthine (IBMX). The enhancement produced by forskolin is suppressed in the presence of adenylate cyclase inhibitors and is not mimicked by the inactive forskolin analogue 1,9-dideoxyforskolin, indicating that, indeed, activation of adenylate cyclase mediates the effects of forskolin in field CA1. Our observations support the idea that changes in intracellular cAMP levels can modulate synaptic efficacy of excitatory glutamatergic synapses in the mammalian hippocampus.


Asunto(s)
Colforsina/farmacología , AMP Cíclico/metabolismo , Hipocampo/efectos de los fármacos , Proteínas Quinasas/efectos de los fármacos , Sinapsis/efectos de los fármacos , 1-Metil-3-Isobutilxantina/farmacología , Inhibidores de Adenilato Ciclasa , Animales , Sinergismo Farmacológico , Activación Enzimática/fisiología , Masculino , Ratas , Ratas Endogámicas
19.
Neurosci Lett ; 104(1-2): 58-64, 1989 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-2554222

RESUMEN

Long-term potentiation of synaptic efficacy (LTP) can be shown to consist of two components: a synaptic and an excitatory postsynaptic potential (EPSP)-spike (E-S) component. The E-S component is expressed as a leftward shift in the curve relating population spike amplitude as a function of EPSP slope. The participation of cholinergic and GABAergic processes in E-S potentiation was studied in field CA1 of rat hippocampal slices. Atropine, a muscarinic antagonist, did not prevent tetanus-induced E-S potentiation. The cholinergic agonist carbachol and the GABAA antagonist picrotoxin produced a leftward shift in the E-S relation; picrotoxin, but not carbachol, prevented the expression of tetanus-induced E-S potentiation. These observations indicate that an increase in the ratio of evoked excitation to inhibition and/or a reduction in tonic inhibition mediated by the activation of GABAA receptors contribute to E-S potentiation produced by high-frequency stimulation.


Asunto(s)
Hipocampo/fisiología , Receptores Colinérgicos/fisiología , Receptores de GABA-A/fisiología , Sinapsis/fisiología , Potenciales de Acción/efectos de los fármacos , Animales , Atropina/farmacología , Carbacol/farmacología , Estimulación Eléctrica , Masculino , Picrotoxina/farmacología , Ratas , Ratas Endogámicas , Receptores Muscarínicos/fisiología
20.
Life Sci ; 62(17-18): 1601-6, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9585143

RESUMEN

Neuronal nicotinic acetylcholine receptors (NAChRs) are pentameric ligand-gated ion channel receptors which exist as different functional subunit combinations which apparently subserve different physiological functions as indicated by molecular biological and pharmacological techniques. It is possible to design and synthesize novel compounds that have greater selective affinities and efficacies than nicotine for different NAChRs, which should translate into different behavioral profiles and therapeutic potentials. Examples of NAChR agonists studied are nicotine, SIB-1508Y, SIB-1553A and epibatidine. These compounds have different degrees of selectivity for human recombinant NAChRs, different neurotransmitter release profiles in vitro and in vivo and differential behavioral profiles. Preclinical studies suggest that SIB-1508Y is a candidate for the treatment of the motor and cognitive deficits of Parkinson's disease, whereas SIB-1553A appears to have potential as a candidate for the treatment of Alzheimer's disease. Epibatidine has a strong analgesic profile, however the ratio between pharmacological activity and undesirable effects is so low that it is difficult to envisage the use of this compound therapeutically. Nicotine has a broad profile of pharmacological activity, for instance demonstrating activity in models for cognition and analgesia. As for epibatidine, the adverse effects of nicotine severely limits its therapeutic use in humans. The discovery of subtype-selective NAChR agonists such as SIB-1508Y and SIB-1553A provides a new class of neuropsychopharmacological agents with better therapeutic ratios than nonspecific agents such as nicotine.


Asunto(s)
Neuronas/ultraestructura , Agonistas Nicotínicos/farmacología , Receptores Nicotínicos/efectos de los fármacos , Animales , Humanos , Neuronas/efectos de los fármacos , Receptores Nicotínicos/metabolismo , Receptores Nicotínicos/fisiología , Especificidad por Sustrato
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