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1.
Clin Epigenetics ; 13(1): 203, 2021 11 03.
Artículo en Inglés | MEDLINE | ID: mdl-34732256

RESUMEN

BACKGROUND: In mucosal barrier interfaces, flexible responses of gene expression to long-term environmental changes allow adaptation and fine-tuning for the balance of host defense and uncontrolled not-resolving inflammation. Epigenetic modifications of the chromatin confer plasticity to the genetic information and give insight into how tissues use the genetic information to adapt to environmental factors. The oral mucosa is particularly exposed to environmental stressors such as a variable microbiota. Likewise, persistent oral inflammation is the most important intrinsic risk factor for the oral inflammatory disease periodontitis and has strong potential to alter DNA-methylation patterns. The aim of the current study was to identify epigenetic changes of the oral masticatory mucosa in response to long-term inflammation that resulted in periodontitis. METHODS AND RESULTS: Genome-wide CpG methylation of both inflamed and clinically uninflamed solid gingival tissue biopsies of 60 periodontitis cases was analyzed using the Infinium MethylationEPIC BeadChip. We validated and performed cell-type deconvolution for infiltrated immune cells using the EpiDish algorithm. Effect sizes of DMPs in gingival epithelial and fibroblast cells were estimated and adjusted for confounding factors using our recently developed "intercept-method". In the current EWAS, we identified various genes that showed significantly different methylation between periodontitis-inflamed and uninflamed oral mucosa in periodontitis patients. The strongest differences were observed for genes with roles in wound healing (ROBO2, PTP4A3), cell adhesion (LPXN) and innate immune response (CCL26, DNAJC1, BPI). Enrichment analyses implied a role of epigenetic changes for vesicle trafficking gene sets. CONCLUSIONS: Our results imply specific adaptations of the oral mucosa to a persistent inflammatory environment that involve wound repair, barrier integrity, and innate immune defense.


Asunto(s)
Inflamación/genética , Membrana Mucosa/anomalías , Enfermedades Periodontales/genética , Sistema Estomatognático/fisiopatología , Adulto , Epigénesis Genética/genética , Epigénesis Genética/inmunología , Femenino , Humanos , Inflamación/fisiopatología , Masculino , Persona de Mediana Edad , Membrana Mucosa/fisiopatología , Enfermedades Periodontales/fisiopatología
3.
Am J Surg Pathol ; 45(5): 627-637, 2021 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-33481384

RESUMEN

Choledochal cyst (CC) is believed to be a mostly Asian disorder. As a clinically defined entity, its pathologic correlates are poorly characterized. Eighty-four resected CCs from the West were reanalyzed. After applying established Japanese criteria, 9/66 with available imaging were disqualified and 10/39 with preoperative cyst typing had to be recategorized. None had been diagnosed with, or evaluated for, pancreatobiliary maljunction, but on retrospective analysis of radiologic images, 12/66 were found to have pancreatobiliary maljunction. The clinical findings were: F/M=5.7; mean age, 48; most (77%) presented with abdominal pain; mean size, 2.9 cm; choledocholithiasis 11%. Gross/histologic examination revealed 3 distinct pathology-based categories: (I) Cystic dilatation of native ducts (81%). (II) Double bile duct (13%), almost all of which were found in women (10/11); all were diagnosed by pathologic examination, and not preoperative diagnosis. (III) Gastrointestinal (GI) duplication type (6%). Microscopic findings of the entire cohort included mucosal-predominant lymphoplasmacytic inflammation (50%), follicular cholangitis (7%), mucosal hyperplasia (43%; 13% with papillae), intestinal metaplasia (10%), BilIN-like hyperplasia (17%), erosion/ulceration (13%), and severe dysplasia-mimicking atypia including "detachment atypia" and micropapillary degeneration (11%). Carcinomatous changes were seen in 14 cases (17%) (high-grade dysplasia/carcinoma in situ in 7, intraductal papillary neoplasm 1, and invasive carcinoma 6); and 13/14 of these occurred in pathologic category I, all with cyst size >1 cm. In conclusion, diagnostic imaging guidelines used in Asia are not routinely used (but should be adopted) in the West. Pathologically, cases designated as CC are classifiable in 3 groups: category 1 (dilated native duct type), more prone to carcinomatous change; category 2, double-duct phenomenon (all but 1 being female in this study); and category 3, GI-type duplication. Overall, 17% of CCs show carcinomatous change (50% of them invasive). CC specimens should be carefully examined with this classification and submitted entirely for assessment of at-risk mucosa and cancerous transformation.


Asunto(s)
Neoplasias de los Conductos Biliares/patología , Conductos Biliares/patología , Carcinoma/patología , Transformación Celular Neoplásica/patología , Quiste del Colédoco/patología , Membrana Mucosa/patología , Neoplasias de los Conductos Biliares/cirugía , Conductos Biliares/anomalías , Conductos Biliares/cirugía , Carcinoma/cirugía , Carcinoma in Situ/patología , Quiste del Colédoco/cirugía , Dilatación Patológica , Femenino , Humanos , Masculino , Persona de Mediana Edad , Membrana Mucosa/anomalías , Membrana Mucosa/cirugía , Estudios Retrospectivos
4.
Esophagus ; 17(4): 440-447, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32172461

RESUMEN

BACKGROUNDS: The width of mucosal defects after endoscopic submucosal dissection (ESD) of esophageal squamous cell carcinoma (ESCC) is known to be a risk factor for esophageal strictures. Although steroid injection and oral steroid have recently been reported as prophylactic treatments, these were shown to be ineffective in a subset of patients with post-ESD mucosal defects involving the entire circumference of the esophagus. The aim of this study was to demonstrate outcome with prophylactic steroid administration for post-ESD mucosal defects involving the entire circumference, and to explore risk factors for esophageal strictures except for circumference of the esophagus. METHODS: Between November 2012 and August 2018, we enrolled patients with post-ESD mucosal defects involving the entire circumference of the esophagus who had received steroid injection (triamcinolone acetonide 50-100 mg, given immediately after ESD) followed by oral steroid (prednisolone 30 mg/day, tapered gradually over 8 weeks) as prophylactic treatment. Esophageal stricture was defined as case where ordinary-sized endoscope could not pass through post-ESD site, thus requiring endoscopic balloon dilation (EBD) repeatedly until relief of stricture was achieved. We retrospectively evaluated the rates of strictures, refractory strictures (requiring ≥ 6 EBD procedures) and unimproved strictures (not improvable by repeated EBD alone) and explored risk factors for strictures. RESULTS: A total of 26 patients met the including criteria. The rates of strictures, refractory strictures, and unimproved strictures were 62%, 38%, and 12%, respectively. The pre-ESD longitudinal extension of the lesion > 5 cm was identified as a risk factor for refractory strictures, suggesting that lesions with this factor had a shorter time to stricture development, required more EBD procedures, and longer EBD durations. CONCLUSION: Although additional study is required in a larger number of patients, careful consideration needs to be given to ESD as an indication for large spreading ESCC involving the entire circumference of esophagus given its high stricture risk.


Asunto(s)
Constricción Patológica/tratamiento farmacológico , Resección Endoscópica de la Mucosa/efectos adversos , Neoplasias Esofágicas/cirugía , Membrana Mucosa/efectos de los fármacos , Triamcinolona Acetonida/administración & dosificación , Anciano , Anciano de 80 o más Años , Cateterismo/instrumentación , Constricción Patológica/prevención & control , Dilatación/métodos , Neoplasias Esofágicas/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Membrana Mucosa/anomalías , Membrana Mucosa/patología , Evaluación de Resultado en la Atención de Salud , Prednisolona/administración & dosificación , Prednisolona/uso terapéutico , Estudios Retrospectivos , Factores de Riesgo , Esteroides/administración & dosificación , Esteroides/uso terapéutico , Triamcinolona Acetonida/uso terapéutico
5.
Laryngoscope ; 130(9): 2208-2212, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-31675133

RESUMEN

OBJECTIVE: Sulcus is an epithelial invagination of the membranous vocal fold. Its phonatory effects are usually attributed to fibrosis, thinning, and/or the absence of the superficial lamina propria (SLP). Surgical treatment is typically focused on reconstruction of the SLP. The purpose of this study is to assess the effects of excision without SLP reconstruction or replacement. METHODS: Records of patients who underwent surgical treatment of sulcus vocalis (Ford type 3) by excision without reconstruction were reviewed for demographic and historical information. Pre- and postoperative stroboscopic examinations were evaluated blindly by fellowship-trained laryngologists using a modified Voice-Vibratory Assessment with Laryngeal Imaging assessment. A Wilcoxon signed-rank test was used to compare pre- and postoperative amplitude, mucosal wave, nonvibrating portion, regularity, erythema, and vascularity. RESULTS: Examinations of 16 vocal folds in 13 patients (8 females:5 males; mean age = 30 years, range 13 to 48 years) were evaluated by six raters each, yielding 168 sets of observations. Statistically significant improvement was seen in amplitude (95% confidence interval [CI] 3.6,14.3), mucosal wave (95% CI 6.1, 17.9), nonvibrating portion (95% CI -19.6, -2.7), erythema (95% CI -19.9, -3.3), and vascularity (95% CI -19.0, -0.75). The parameter of regularity, although improved, did not prove to be significant. CONCLUSION: Excision alone appears to be an adequate and generally successful treatment for sulcus vocalis (Ford type 3). In contrast to established paradigms, restoration of the SLP does not appear to be essential to meaningful clinical improvement. Significant pathologic effects of sulcus vocalis may result from epithelial abnormalities alone. LEVEL OF EVIDENCE: 4 Laryngoscope, 130:2208-2212, 2020.


Asunto(s)
Enfermedades de la Laringe/cirugía , Mucosa Laríngea/cirugía , Membrana Mucosa/cirugía , Pliegues Vocales/cirugía , Adolescente , Adulto , Femenino , Humanos , Enfermedades de la Laringe/patología , Mucosa Laríngea/anomalías , Masculino , Persona de Mediana Edad , Membrana Mucosa/anomalías , Estudios Retrospectivos , Estroboscopía , Resultado del Tratamiento , Pliegues Vocales/patología , Adulto Joven
6.
J Negat Results Biomed ; 16(1): 9, 2017 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-28316284

RESUMEN

We aimed to search for mutations in the germline and somatic DNA of the TEK gene and to analyze the expression level of Src and phospho-Src (p-Src) in tumor and healthy tissues from patients with facial cutaneo-mucosal venous malformations (VMCM). Eligible patients from twelve families and thirty healthy controls were recruited respectively at the Departments of Stomatology and Oral Surgery, and Transfusion Medicine of Tlemcen University Medical Centre. Immunoblot analyses of Src and p-Src were performed after direct DNA sequencing. No somatic or germline mutations were found in all the 23 exons and their 5' and 3' intronic flanking regions, except for one case in which a c.3025+20-3025+22 del mutation was highlighted at the intron 15, both in the germline and somatic DNA. Additionally, elevated expression levels of Src and p-Src were observed only in the patient with such mutation. However, when normalized to ß-actin, the overall relative expression levels of both Src and p-Src were significantly increased in VMCM tissues when compared to healthy tissues (for both comparisons, p <0.001). In conclusion, we confirm the outcomes of our previous work suggesting that VMCM can develop independently of mutation of the TEK gene. Additionally, the results for Src activity are of particular interest in the context of specific targeted therapies and biological diagnosis. Nevertheless, such a conclusion should be confirmed through a mechanistic study and/or in a satisfactory number of patients.


Asunto(s)
Cara/anomalías , Membrana Mucosa/anomalías , Mutación/genética , Receptor TIE-2/genética , Anomalías Cutáneas/genética , Malformaciones Vasculares/genética , Familia-src Quinasas/metabolismo , Adolescente , Secuencia de Aminoácidos , Secuencia de Bases , Femenino , Humanos , Masculino , Fosforilación , Receptor TIE-2/química , Anomalías Cutáneas/patología , Malformaciones Vasculares/patología
7.
Rev. med. Rosario ; 80(2): 63-74, mayo-ago. 2014. ilus
Artículo en Español | LILACS | ID: lil-725905

RESUMEN

El cáncer colorrectal (CCR) es una de las principales causas de morbilidad y mortalidad a nivel mundial. Clásicamente se considera a los adenomas como las lesiones precursoras del CCR y se estipula un tiempo de 10 a 15 años para completar la secuencia adenoma-carcinoma. El CCR evoluciona a través de la acumulación progresiva de alteraciones genéticas y epigenéticas, las que conducen a la transformación de la mucosa colónica normal en cáncer invasivo. La identificación de diferentes vías moleculares de carcinogénesis colorrectal ha demostrado la naturaleza heterogénea del cáncer colónico. De reciente descripción, las lesiones aserradas muestran cambios moleculares y patológicos distintos a los adenomas tradicionales, estimándose que presentan un tiempo más acelerado de evolución hacia la malignidad. El objetivo de esta revisión es actualizar conocimientos sobre la génesis tumoral y sus bases biomoleculares a fin de posibilitar su aplicación a etapas clínicas concretas como la prevención y el tratamiento


Colorectal cancer (CRC) is one of the main causes of morbidity and mortality worldwide. Adenomas are classically regarded as precursor lesions of CRC and between 10 and 15 years is thought to elapse to complete the adenoma-carcinoma sequence. CRC evolves through the progressive accumulation of genetic and epigenetic alterations that lead to invasive cancer through the transformation of normal colonic mucosa. The identification of different molecular pathways of colorectal carcinogenesis has demonstrated the heterogeneous nature of colon cancer. Recent description of serrated lesions shows molecular and pathological changes other than traditional adenomas with an estimated faster time of progression to malignancy. The aim of this review is to update the knowledge about tumorigenesis and its biomolecular basis for clinical application in early stages providing firm ground for prevention and treatment


Asunto(s)
Humanos , Adulto , Colonoscopía , Epigénesis Genética/genética , Genes Relacionados con las Neoplasias/genética , Lesiones Precancerosas/patología , Neoplasias Colorrectales/patología , Prevención de Enfermedades , Diagnóstico/prevención & control , Fenotipo , Herencia/genética , Inestabilidad Cromosómica/genética , Inestabilidad de Microsatélites , Literatura de Revisión como Asunto , Membrana Mucosa/anomalías , Metilación de ADN
8.
J Assoc Physicians India ; 62(8): 704-5, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25856939
9.
Dermatol Online J ; 18(9): 5, 2012 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-23031372

RESUMEN

A 12-year-old girl presented with extensive epidermal nevi, new onset seizures, mental retardation, and oral and ocular abnormalities. We briefly review the case and epidermal nevus syndrome (ENS), which is characterized by epidermal nevi occurring in conjunction with neurologic, ocular, skeletal, and/or other system involvement.


Asunto(s)
Anomalías del Ojo/diagnóstico , Discapacidad Intelectual/diagnóstico , Membrana Mucosa/anomalías , Nevo Sebáceo de Jadassohn/diagnóstico , Convulsiones/diagnóstico , Neoplasias Cutáneas/diagnóstico , Trastornos de la Visión/diagnóstico , Adolescente , Biopsia , Diplopía/diagnóstico , Femenino , Humanos , Nevo Sebáceo de Jadassohn/patología , Trastornos Respiratorios/diagnóstico , Neoplasias Cutáneas/patología
10.
Am J Surg Pathol ; 34(10): 1528-43, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20871226

RESUMEN

X-linked intestinal pseudo-obstruction, a rare disorder caused by mutations in FLNA, the gene encoding the cytoskeletal protein filamin A, has been regarded as a hereditary enteric neuropathy largely on the basis of sparse and incomplete pathologic studies. Diffuse abnormal layering of small intestinal smooth muscle (DAL) is a rare malformation, which has only been described in 4 patients (all male, 3 in the same family) with intestinal pseudo-obstruction. We report DAL in 5 male patients (2 families) with intestinal pseudo-obstruction and mutations in FLNA. Light microscopic, ultrastructural, and immunohistochemical studies showed abnormal lamination of the small intestinal muscularis propria with associated absent or severely reduced FLNA immunoreactivity. Intestinal samples from the oldest patient in the series, a teenager, showed multinucleate myocytes in small and large intestine, along the submucosal surface of the muscularis propria. As neither DAL nor the pattern of myocyte multinucleation observed in our patients have been described outside the context of X-linked intestinal pseudo-obstruction, these histopathologic features may be specific for this hereditary disorder and suggest an underlying myopathic basis for dysmotility in affected patients.


Asunto(s)
Proteínas Contráctiles/genética , Enfermedades Genéticas Ligadas al Cromosoma X/genética , Seudoobstrucción Intestinal/genética , Intestino Delgado/anomalías , Proteínas de Microfilamentos/genética , Músculo Liso/anomalías , Mutación , Adolescente , Niño , Proteínas Contráctiles/metabolismo , Femenino , Filaminas , Enfermedades Genéticas Ligadas al Cromosoma X/metabolismo , Enfermedades Genéticas Ligadas al Cromosoma X/patología , Humanos , Recién Nacido , Seudoobstrucción Intestinal/metabolismo , Seudoobstrucción Intestinal/patología , Intestino Grueso/patología , Intestino Delgado/metabolismo , Masculino , Proteínas de Microfilamentos/metabolismo , Membrana Mucosa/anomalías , Membrana Mucosa/metabolismo , Músculo Liso/metabolismo , Miocitos del Músculo Liso/metabolismo , Miocitos del Músculo Liso/patología , Linaje
11.
J Pediatr Surg ; 44(11): 2211-5, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19944235

RESUMEN

Herein is reported case of an otherwise healthy full-term infant girl who presented with numerous spontaneous intestinal perforations with congenital absence of intestinal muscularis mucosae and muscularis propria. Few other cases are reported in the English literature with varying presentations. We review those cases, theories of pathogenesis, embryology, and possible connections to various clinical presentations.


Asunto(s)
Atresia Intestinal/patología , Intestinos/anomalías , Músculo Liso/anomalías , Femenino , Humanos , Íleon/anomalías , Íleon/patología , Íleon/cirugía , Recién Nacido , Atresia Intestinal/cirugía , Perforación Intestinal/congénito , Perforación Intestinal/patología , Perforación Intestinal/cirugía , Intestinos/patología , Intestinos/cirugía , Masculino , Membrana Mucosa/anomalías , Membrana Mucosa/patología , Membrana Mucosa/cirugía , Músculo Liso/patología , Músculo Liso/cirugía
12.
Am J Pathol ; 175(4): 1442-52, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19762715

RESUMEN

Kindlin-1 is an epithelial-specific member of the novel kindlin protein family, which are regulators of integrin functions. Mutations in the gene that encodes Kindlin-1, FERMT1 (KIND1), cause the Kindler syndrome (KS), a human disorder characterized by mucocutaneous fragility, progressive skin atrophy, ulcerative colitis, photosensitivity, and propensity to skin cancer. Our previous studies indicated that loss of kindlin-1 resulted in abnormalities associated with integrin functions, such as adhesion, proliferation, polarization, and motility of epidermal cells. Here, we disclosed novel FERMT1 mutations in KS and used them, in combination with small-interfering RNA, protein, and imaging studies, to uncover new functions for kindlin-1 in keratinocytes and to discern the molecular pathology of KS. We show that kindlin-1 forms molecular complexes with beta1 integrin, alpha-actinin, migfilin, and focal adhesion kinase and regulates cell shape and migration by controlling lamellipodia formation. Kindlin-1 governs these processes by signaling via Rho family GTPases, and it is required to maintain the pool of GTP-bound, active Rac1, RhoA and Cdc42, and the phosphorylation of their downstream effectors p21-activated kinase 1, LIM kinase, and cofilin. Loss of these kindlin-1 functions forms the biological basis for the epithelial cell fragility and atrophy in the pathology of KS.


Asunto(s)
Queratinocitos/enzimología , Proteínas de la Membrana/metabolismo , Proteínas de Neoplasias/metabolismo , Seudópodos/enzimología , Proteínas de Unión al GTP rho/metabolismo , Anomalías Múltiples/enzimología , Anomalías Múltiples/patología , Adulto , Línea Celular Transformada , Movimiento Celular , Forma de la Célula , Niño , Activación Enzimática , Adhesiones Focales/enzimología , Guanosina Trifosfato/metabolismo , Humanos , Queratinocitos/patología , Persona de Mediana Edad , Modelos Biológicos , Membrana Mucosa/anomalías , Membrana Mucosa/patología , Fenotipo , Fosforilación , Unión Proteica , ARN Interferente Pequeño/metabolismo , Anomalías Cutáneas/enzimología , Anomalías Cutáneas/patología , Síndrome
15.
Rev. cuba. cir ; 43(3/4)jul.-dic. 2004.
Artículo en Español | LILACS, CUMED | ID: lil-628197

RESUMEN

Se realiza un estudio de 50 pacientes que padecieron de poliposis nasal. La mayoría de los pacientes están comprendidos en la 4ta. y 5ta. décadas de la vida, con predominio del sexo masculino. El tiempo de evolución de la enfermedad que predominó en los pacientes fue de 1 a 4 años. Los antecedentes alérgicos y la eosinofilia sanguínea estuvieron presentes en nuestros casos. Todos los pacientes recibieron tratamiento quirúrgico, que consistió en polipectomía nasal anterior, en ocasiones asociada a la técnica de maxiloetmoidectomía. En las muestras obtenidas predominó, desde el punto de vista macroscópico, el aspecto polipoide, la mucosa engrosada y la secreción mucoserosa. Asimismo, en el análisis histopatológico se observó hipertrofia epitelial, engrosamiento de la membrana basal, edema e hiperplasia glandular en la lámina propia(AU)


A study of 50 patients suffering from nasal polyposis was conducted. Most of the patients were 40 and 50 years old. It was observed a predominance of males. The time of the evolution of the disease prevailing among the patients was from 1 to 4 years. The allergy history and blood eosynophilia were present in our cases. All the patients underwent surgery, which consisted in anterior nasal polypectomy on occasions associated with the maxilloethmoidectomy technique. In the samples obtained it was observed a predominance, from the macroscopical point of view, of the polypoid aspect, the thickened mucosa and the mucoserous secretion. Likewise, epithelial hypertrophy, thickening of the nasal membrane, edema and glandular hyperplasia in the own lamina were found in the histopathological analysis(AU)


Asunto(s)
Humanos , Masculino , Persona de Mediana Edad , Pólipos Nasales/cirugía , Pólipos Nasales/diagnóstico , Hiperplasia/terapia , Membrana Mucosa/anomalías
17.
Pediatr Surg Int ; 18(5-6): 532-4, 2002 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12415403

RESUMEN

In a 1-month-old infant with a mucosal-line left hemiperineal defect associated with penoscrotal hypospadias, penoscrotal transposition (PST) and an overhanging caudal skin-covered soft-tissue flap resembling a caudal appendage, perineal anatomy could be restored by excising the mucosa and using the overhanging flap to cover the resultant defect. The PST was corrected at the same time. Squamous, gastric, small-intestinal, and respiratory epithelia were present histologically in the mucosa in addition to adjacent cartilaginous elements. A caudal duplication that had ruptured in utero through the hemiperineum could explain the anomaly.


Asunto(s)
Anomalías Múltiples/cirugía , Hipospadias/complicaciones , Perineo/anomalías , Escroto/anomalías , Procedimientos Quirúrgicos Urológicos Masculinos , Humanos , Hipospadias/cirugía , Lactante , Masculino , Membrana Mucosa/anomalías , Membrana Mucosa/cirugía , Perineo/cirugía , Rotura
18.
Cir Pediatr ; 14(1): 38-40, 2001 Jan.
Artículo en Español | MEDLINE | ID: mdl-11339119

RESUMEN

The authors report a case of membranous atresia of the esophagus. Diagnosis of this rare malformation was made intraoperatively, and resection and primary anastomosis were performed immediately. A brief review of the literature is included on the various types of esophageal atresia.


Asunto(s)
Atresia Esofágica/etiología , Adulto , Femenino , Humanos , Membrana Mucosa/anomalías
19.
J Neurosci ; 19(21): 9298-305, 1999 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-10531434

RESUMEN

Transcripts for the beta2 and the beta4 nicotinic acetylcholine receptor (nAChR) subunits are found throughout the CNS and the peripheral nervous system. These two beta subunits can form heteromultimeric channels with any of the alpha2, alpha3, alpha4, or alpha5 subunits in heterologous expression systems. Nonetheless, the subunit composition of native nAChRs and the role of different nAChR subtypes in vivo remain unclear. We prepared null mutations for the beta2 and the beta4 genes and bred beta2-/-beta4-/- mice by mating mice of identical beta2-/-beta4+/- or beta2+/-beta4-/- genotype. The beta2-/- and the beta4-/- single-mutant mice grow to adulthood with no visible phenotypic abnormalities. The beta2-/-beta4-/- double mutants survive to birth but have impaired growth and increased perinatal mortality. They also present enlarged bladders with dribbling urination and develop urinary infection and bladder stones. The ocular pupils are widely dilated and do not constrict in response to light. Histological studies revealed no significant abnormalities of brain or peripheral tissues except for hyperplasia in the bladder mucosa of beta4-/- and beta2-/-beta4-/- mutants. Bladder strips from beta2-/-beta4-/- mice did not respond to nicotine but contracted when stimulated with a muscarinic agonist or electric field stimulation. Bladder strips from beta4 mutants did not respond to nicotine despite the absence of major bladder dysfunction in vivo. Acetylcholine-activated whole-cell currents were absent in superior cervical ganglion neurons from beta2-/-beta4-/- mice and reduced in neurons from beta4-/- mice. Although there is apparent redundancy and a superficially normal phenotype in beta2-/- and beta4-/- mice, physiological studies indicate major deficits in the beta4-/- mice. Our previous description of a similar phenotype in alpha3-/- mice and the current data suggest that the alpha3 and the beta4 subunits are major components in autonomic nAChRs. The phenotype of the beta2-/-beta4-/- and alpha3-/- mice resembles the autosomal recessive megacystis-microcolon-hypoperistalsis syndrome in humans.


Asunto(s)
Enfermedades del Sistema Nervioso Autónomo/genética , Neuronas/fisiología , Receptores Nicotínicos/fisiología , Ganglio Cervical Superior/fisiopatología , Animales , Enfermedades del Sistema Nervioso Autónomo/fisiopatología , Células Cultivadas , Cruzamientos Genéticos , Exones , Anomalías del Ojo/genética , Anomalías del Ojo/patología , Femenino , Biblioteca Genómica , Intrones , Sustancias Macromoleculares , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos , Ratones Noqueados , Membrana Mucosa/anomalías , Membrana Mucosa/patología , Neuronas/efectos de los fármacos , Nicotina/farmacología , Receptores Nicotínicos/deficiencia , Receptores Nicotínicos/genética , Ganglio Cervical Superior/fisiología , Vejiga Urinaria/anomalías , Vejiga Urinaria/patología
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