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2.
Plant Biol (Stuttg) ; 17(3): 639-46, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25524599

RESUMEN

The androgynophore column, a distinctive floral feature in passion flowers, is strongly crooked or bent in many Passiflora species pollinated by bats. This is a floral feature that facilitates the adaptation to bat pollination. Crooking or bending of plant organs are generally caused by environmental stimulus (e.g. mechanical barriers) and might involve the differential distribution of auxin. Our aim was to study the role of the perianth organs and the effect of auxin in bending of the androgynophore of the bat-pollinated species Passiflora mucronata. Morpho-anatomical characterisation of the androgynophore, including measurements of curvature angles and cell sizes both at the dorsal (convex) and ventral (concave) sides of the androgynophore, was performed on control flowers, flowers from which perianth organs were partially removed and flowers treated either with auxin (2,4-dichlorophenoxyacetic acid; 2,4-D) or with an inhibitor of auxin polar transport (naphthylphthalamic acid; NPA). Asymmetric growth of the androgynophore column, leading to bending, occurs at a late stage of flower development. Removing the physical constraint exerted by perianth organs or treatment with NPA significantly reduced androgynophore bending. Additionally, the androgynophores of plants treated with 2,4-D were more curved when compared to controls. There was a larger cellular expansion at the dorsal side of the androgynophores of plants treated with 2,4-D and in both sides of the androgynophores of plants treated with NPA. This study suggests that the physical constraint exerted by perianth and auxin redistribution promotes androgynophore bending in P. mucronata and might be related to the evolution of chiropterophily in the genus Passiflora.


Asunto(s)
Quirópteros , Flores/crecimiento & desarrollo , Ácidos Indolacéticos/metabolismo , Passiflora/crecimiento & desarrollo , Polinización , Ácido 2,4-Diclorofenoxiacético/farmacología , Animales , Evolución Biológica , Flores/metabolismo , Passiflora/metabolismo
3.
Int J Pediatr Otorhinolaryngol ; 58(3): 255-7, 2001 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-11335016

RESUMEN

Lymphangiomas present commonly in the head and neck region with over 90% of lesions diagnosed before 2 years of age. These lesions have rarely been reported as a cause of acute upper airway obstruction and to date, there are very few reports in the literature documenting the presence of lymphangiomas in the larynx. We present the case of a previously asymptomatic 13-year-old girl with Joubert's syndrome, who presented with acute airway obstruction while undergoing extubation for a routine dental procedure. Near-complete obstruction of her supraglottis from a lymphangioma necessitated tracheotomy to secure the airway. The diagnostic work-up and management of this patient and her post-operative course are discussed. This case illustrates the insidious presentation of a laryngeal lymphangioma and emphasizes the management options for such patients.


Asunto(s)
Obstrucción de las Vías Aéreas/etiología , Neoplasias Laríngeas/complicaciones , Linfangioma/complicaciones , Enfermedad Aguda , Adolescente , Femenino , Humanos , Neoplasias Laríngeas/patología , Linfangioma/patología
5.
J Otolaryngol ; 30(1): 24-8, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11770969

RESUMEN

OBJECTIVE: Pregnancy may confer a number of conditions related to the head and neck. The objective of this study was to evaluate the clinical manifestations of sinonasal pathology that occur during pregnancy. METHODS: Thirty-three pregnant patients were evaluated for the occurrence of rhinorrhea, congestion, epistaxis, or acute sinusitis during the first trimester of pregnancy, controlling with 28 women of child-bearing age. A visual analogue scale was used to grade the severity of each symptom. Statistical analysis was carried out to assess for significant differences in the prevalence and severity of symptomatology between cases and controls. RESULTS: Compared to the control group, there was no statistically significant difference in the prevalence of congestion, epistaxis, rhinorrhea, or acute sinusitis. There was no statistically significant difference in the severity of any presenting symptom between pregnant and control group patients. CONCLUSION: Pregnancy is not associated with an increased prevalence or severity of nasal symptomatology during early pregnancy. The influence of hormonal changes on nasal physiology during pregnancy is discussed with a view toward safe management.


Asunto(s)
Epistaxis/epidemiología , Complicaciones del Embarazo/epidemiología , Rinitis/epidemiología , Sinusitis/epidemiología , Adulto , Epistaxis/terapia , Femenino , Humanos , Persona de Mediana Edad , Embarazo , Complicaciones del Embarazo/terapia , Prevalencia , Rinitis/terapia , Sinusitis/terapia
7.
Curr Allergy Asthma Rep ; 1(3): 193-201, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11892036

RESUMEN

Rhinitis is a chronic condition of the nasal mucosa that affects a large segment of the population. The symptoms of rhinitis occur in a variety of sinonasal conditions, which may be broadly classified as allergic (seasonal or perennial) or nonallergic (infectious or a number of noninfectious etiologies) based on the presence or absence of atopy. The cytokine profile and inflammatory patterns underlying these two conditions vary because of certain differences in their pathophysiology as discussed in this review.


Asunto(s)
Inflamación/fisiopatología , Rinitis Alérgica Perenne/fisiopatología , Rinitis/etiología , Citocinas/fisiología , Humanos , Mucosa Nasal/fisiopatología
8.
J Otolaryngol ; 29(1): 7-12, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10709165

RESUMEN

A study was conducted to assess outcome analysis in acetylsalicylic acid (ASA) triad patients after endoscopic sinus surgery (ESS). The control group consisted of patients with chronic sinusitis, with or without asthma, who had also undergone ESS. The study group contained 18 patients with the classic triad who were compared with 22 controls. The study was conducted in retrospective fashion highlighting clinical presentation, radiologic evaluation, surgical findings, and recurrence rate of nasal polyps. Although both groups had a relatively similar age of onset of symptoms, the symptomatic picture was different in the two groups. Radiologic evaluation of the nose and paranasal sinuses revealed more extensive involvement of the sinuses in ASA triad patients. Furthermore, ASA triad patients underwent a greater number of repeat operations. This review suggests that ASA triad patients respond less well to surgical intervention and that other treatment modalities should perhaps be explored.


Asunto(s)
Antiinflamatorios no Esteroideos/efectos adversos , Aspirina/efectos adversos , Asma/complicaciones , Hipersensibilidad a las Drogas/complicaciones , Endoscopía , Pólipos Nasales/complicaciones , Sinusitis/cirugía , Adulto , Edad de Inicio , Anciano , Enfermedad Crónica , Sinusitis del Etmoides/complicaciones , Sinusitis del Etmoides/cirugía , Femenino , Estudios de Seguimiento , Humanos , Estudios Longitudinales , Masculino , Sinusitis Maxilar/complicaciones , Sinusitis Maxilar/cirugía , Persona de Mediana Edad , Pólipos Nasales/cirugía , Recurrencia Local de Neoplasia/patología , Reoperación , Estudios Retrospectivos , Sinusitis/complicaciones , Sinusitis del Esfenoides/complicaciones , Sinusitis del Esfenoides/cirugía , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
10.
J Otolaryngol ; 27(5): 252-7, 1998 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9800622

RESUMEN

OBJECTIVE: This study was conducted to assess treatment results in patients undergoing functional endoscopic sinus surgery for chronic sinusitis, with evaluation of prognostic indicators of success and failure. METHOD: The study included 393 patients who underwent endoscopic sinus surgery for chronic sinusitis over a 4-year period. The diagnosis of chronic sinusitis was based on ongoing symptomatology for greater than 3 months and the presence of mucosal disease on computerized tomography (CT). A retrospective analysis was done looking at patient data, presenting symptoms, CT findings, operative reports, pathology reports, and outcome at 6- and 12-month follow-up. The prognostic significance of selected factors was evaluated using chi-square analysis. RESULTS: A positive history for asthma, allergy, and ASA triad was present in 29.5%, 34.6%, and 10.9% of patients, respectively. Previous sinus surgery was done in 31.9%, and 15.7% of patients were smokers. The most common presenting complaint was nasal congestion/obstruction, followed by facial pain/headaches and olfactory disturbance. A positive outcome was achieved in 80.5% of patients at 6 months and in 69.7% at 12-month follow-up. Revision surgery within a year was needed in 4.1% of patients. Factors affecting outcome included asthma, smoking, polyposis, previous surgery, and pansinusitis. CONCLUSIONS: Extent of disease, as reflected by polyposis, pansinusitis, and premorbid history, is the most important determinant of outcome. Concomitant changes in ciliary motility secondary to asthma or smoking further impede surgical outcome. Future studies focusing on the disease process of chronic sinusitis are needed.


Asunto(s)
Endoscopía , Sinusitis/cirugía , Adolescente , Adulto , Anciano , Distribución de Chi-Cuadrado , Enfermedad Crónica , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento
11.
J Otolaryngol ; 26(1): 13-9, 1997 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9055168

RESUMEN

OBJECTIVE: Neurofibromatosis (NF) is a genetic disease with a wide variety of clinical manifestations. Eight patients with otolaryngologic manifestations of NF are presented. This represents 4.9% of all NF patients currently registered at the NF clinic at the Montreal Children's Hospital. METHODS: Clinical manifestations are divided into cosmetic and functional categorizations. RESULTS: Five patients presented with cosmetic deformities, the most common being an enlarging facial mass. Three patients presented with functional impairments, the most common being hearing loss and airway obstruction. Radiologic findings include the presence of plexiform neurofibromas and airway obstruction. Management was individualized to improve cosmesis and/or function. In the literature, the incidence of head and neck manifestations in patients with NF varies between 14% and 37%. Cosmetic lesions include pigmentary changes (café-au-lait spots), prominent neurofibromas, and osseous lesions. Functional deficits include hearing loss, speech and voice abnormalities, airway obstruction, dysphagia, facial paresis, lip incompetence, and impaired mastication. Diagnosis of NF-1 (classic von Recklinghausen's disease) and NF-2 (bilateral acoustic schwannomas) can be made using specific criteria. Management of patients with NF is individualized depending on the cosmetic deformity, functional impairment, and/or malignant potential of tumours. NF is progressive and has no cure. Prognosis depends on individual clinical manifestations, surgical resectability, and the potential for sarcomatous degeneration. CONCLUSION: This study provides a unique classification of the otolaryngologic findings in NF, giving the otolaryngologist an operable framework for diagnosis, treatment and prognosis.


Asunto(s)
Trastornos de Deglución/etiología , Parálisis Facial/etiología , Trastornos de la Audición/etiología , Neurofibromatosis 1/complicaciones , Síndromes de la Apnea del Sueño/etiología , Trastornos del Habla/etiología , Obstrucción de las Vías Aéreas/etiología , Niño , Preescolar , Humanos , Lactante , Pronóstico
12.
J Am Coll Cardiol ; 19(6): 1294-302, 1992 May.
Artículo en Inglés | MEDLINE | ID: mdl-1564230

RESUMEN

Cine nuclear magnetic resonance (NMR) imaging was used to serially measure cardiovascular function in 17 patients with New York Heart Association class II or III heart failure and left ventricular ejection fraction less than or equal to 45% who were treated for 3 months with benazepril hydrochloride, a new angiotensin-converting enzyme inhibitor, while continuing treatment with diuretic agents and digoxin. Interobserver reproducibilities for ejection fraction (r = 0.94, SEE 3.3%), end-systolic volume (r = 0.98, SEE 10.6 ml), end-diastolic volume (r = 0.99, SEE 8.29 ml), end-systolic mass (r = 0.96, SEE 15.4 g), end-systolic wall stress (r = 0.91, SEE 10 dynes.s.cm-5) and end-systolic stress/volume ratio (r = 0.85, SEE 0.13) demonstrated applicability of cine NMR imaging for the serial assessment of cardiovascular function in response to pharmacologic interventions in patients with heart failure. During 12 weeks of treatment with benazepril, ejection fraction increased progressively from 29.7 +/- 2.2% (mean +/- SEM) to 36 +/- 2.2% (p less than 0.05), end-diastolic volume decreased from 166 +/- 14 to 158 +/- 12 ml (p = NS), end-systolic volume decreased from 118 +/- 12 to 106 +/- 11 ml (p less than 0.05), left ventricular mass decreased from 235 +/- 13 to 220 +/- 12 g (p less than 0.05), end-systolic wall stress decreased 29% from 90 +/- 5 to 64 +/- 5 dynes.s.cm-5 (p less than 0.05), end-systolic pressure decreased from 92.6 +/- 3.7 to 78.8 +/- 5.3 (p less than 0.05) and end-systolic stress/volume ratio, a load-independent index of contractility, decreased from 0.83 +/- 0.05 to 0.67 +/- 0.06 (p less than 0.05), demonstrating that improved ejection fraction is due to afterload reduction.


Asunto(s)
Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Benzazepinas/uso terapéutico , Cardiomiopatía Dilatada/diagnóstico , Imagen por Resonancia Magnética/métodos , Películas Cinematográficas , Análisis de Varianza , Presión Sanguínea/efectos de los fármacos , Presión Sanguínea/fisiología , Cardiomiopatía Dilatada/tratamiento farmacológico , Cardiomiopatía Dilatada/epidemiología , Cardiomiopatía Dilatada/fisiopatología , Evaluación de Medicamentos , Quimioterapia Combinada , Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/tratamiento farmacológico , Insuficiencia Cardíaca/epidemiología , Insuficiencia Cardíaca/fisiopatología , Frecuencia Cardíaca/efectos de los fármacos , Frecuencia Cardíaca/fisiología , Humanos , Imagen por Resonancia Magnética/estadística & datos numéricos , Películas Cinematográficas/estadística & datos numéricos , Variaciones Dependientes del Observador , Análisis de Regresión , Método Simple Ciego , Volumen Sistólico/efectos de los fármacos , Volumen Sistólico/fisiología
13.
Otolaryngol Head Neck Surg ; 104(6): 818-25, 1991 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-1908974

RESUMEN

The hemitongue paralysis that occurs as a result of a classic hypoglossal-facial nerve crossover procedure can result in profound functional deficits in speech, mastication, and swallowing. The procedure is not an option in patients with bilateral facial paralysis or those at risk for combined cranial nerve deficits. To address some of the drawbacks and limitations of this classic procedure, we developed the hypoglossal-facial nerve interpositional jump graft (12-7 jump graft) procedure. This procedure involves interposing a nerve graft between a partially severed but functionally intact twelfth cranial nerve and the degenerated seventh cranial nerve, and is often combined with other reanimation procedures. To date, we have performed 33 12-7 jump graft procedures in 30 patients (three were treated for bilateral facial paralysis); this report describes the procedure and its indications, and details the results of 23 procedures performed in 20 patients for whom 24-month follow-up data are available. Twelfth nerve deficits occurred in only three patients in this report. Recovery of facial function began between 3 and 24 months postoperatively. Facial tone and symmetry were achieved in every patient, no patient had significant mass movement, and 13 patients (two of whom were treated for bilateral facial paralysis) had excellent and three had superb restoration of facial movement. These results show the 12-7 jump graft to be a valuable adjunct for facial reanimation in selected patients.


Asunto(s)
Nervio Facial/cirugía , Parálisis Facial/cirugía , Nervio Hipogloso/cirugía , Transferencia de Nervios/métodos , Lengua/inervación , Adolescente , Adulto , Anciano , Atrofia/prevención & control , Niño , Parálisis Facial/rehabilitación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Lengua/patología
14.
Am J Otol ; 12(3): 163-8, 1991 May.
Artículo en Inglés | MEDLINE | ID: mdl-1882962

RESUMEN

Gadolinium-enhanced magnetic resonance imaging was used in the evaluation of the facial nerve in four patients with idiopathic facial paralysis and six with herpes zoster oticus (HZO). Enhancement of the facial nerve was seen in all patients with Bell's palsy, and 50 percent of patients with HZO. The most consistent area of enhancement in both disorders involved the premeatal and labyrinthine segments. Although the images showed changes consistent with the type of viral process that is known to occur in these disorders, we found no significant correlation between the intensity or pattern of facial nerve enhancement on the images, the severity or duration of the disease, or the patient's prognosis for recovery. Nevertheless, gadolinium-enhanced MRI does have a place in the evaluation and decisions for management of select cases of facial paralysis.


Asunto(s)
Medios de Contraste , Nervio Facial/patología , Parálisis Facial/diagnóstico , Imagen por Resonancia Magnética , Disinergia Cerebelosa Mioclónica/diagnóstico , Compuestos Organometálicos , Ácido Pentético , Adolescente , Adulto , Anciano , Femenino , Gadolinio DTPA , Humanos , Masculino , Persona de Mediana Edad , Intensificación de Imagen Radiográfica
17.
Head Neck ; 12(6): 520-3, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-2124208

RESUMEN

While less common than stricture, recurrent neoplasm, and neuromuscular dysfunction, neopharyngeal diverticulum must be considered in the differential diagnosis of postlaryngectomy dysphagia. Symptoms of difficulty clearing the neopharynx during and after a swallow, with regurgitation of undigested material, should alert the clinician to this possibility. Experience with 3 postlaryngectomy patients with anterior neopharyngeal divericulae serve as the springboard for discussion of the clinical spectrum, radiologic features, contributory pathophysiologic factors, and therapeutic options concerning this condition. Surgical indications, approaches, and potential hazards are reviewed.


Asunto(s)
Divertículo/etiología , Laringectomía , Enfermedades Faríngeas/etiología , Anciano , Trastornos de Deglución/etiología , Humanos , Laringectomía/efectos adversos , Masculino , Persona de Mediana Edad
18.
Laryngoscope ; 100(10 Pt 1): 1037-42, 1990 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-2215032

RESUMEN

As functional endoscopic sinus surgery continues to gain popularity and support, the necessity for a clear and accurate understanding of the anatomy of the ostiomeatal complex becomes essential. To clarify this anatomy, serial cadaver dissections were performed and the anatomy of the ostiomeatal complex was detailed in three dimensions, with an emphasis on precise localization of the internal os of the maxillary sinus as it relates to the orbit, natural antronasal canal, and ethmoid infundibulum. Measurements of the position of the internal os relative to the position of the anterior and posterior walls of the maxillary sinus and the position of the orbit were taken. The dimensions and configuration of the antronasal canal and its relationship to the infundibulum were also detailed. These measurements and relationships must be understood for an endoscopic sinus surgeon to locate the natural ostia without injuring the orbit.


Asunto(s)
Endoscopía , Seno Maxilar/anatomía & histología , Cadáver , Humanos , Seno Maxilar/cirugía
19.
Laryngoscope ; 100(10 Pt 1): 1062-7, 1990 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-2215037

RESUMEN

This report describes our experiences and evolving philosophy with regard to managing segmental facial nerve injuries. We present the results of 13 facial nerve repairs of traumatic injury to a segment of the facial nerve. All peripheral facial nerve branches contribute essential elements to normal mimetic facial movement; therefore, we recommend early, appropriate repair of the nerve segment. This recommendation is based on principles established for managing disruptions of the main trunk of the facial nerve. It offers the patient the chance for complete recovery of facial function.


Asunto(s)
Traumatismos del Nervio Facial , Nervio Facial/cirugía , Adulto , Niño , Femenino , Estudios de Seguimiento , Humanos , Masculino , Heridas no Penetrantes/cirugía , Heridas Penetrantes/cirugía
20.
Am J Surg ; 160(4): 382-6, 1990 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-2221238

RESUMEN

A retrospective study of 35 patients who underwent early facial reanimation following extirpative parotid and temporal bone surgery requiring facial nerve sacrifice was performed. Regional facial reanimation performed immediately or within several days included 16 patients who underwent temporalis muscle transposition and 27 who underwent gold weight or eyespring lid reanimation with lower lid tightening. Simultaneous nerve grafts or nerve crossover procedures were performed in 22 patients. The authors' favored approaches to facial reanimation are discussed, with an emphasis on the value of early reanimation using properly selected techniques.


Asunto(s)
Parálisis Facial/cirugía , Neoplasias de la Parótida/cirugía , Complicaciones Posoperatorias , Neoplasias Craneales/cirugía , Hueso Temporal/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Párpados/cirugía , Parálisis Facial/etiología , Femenino , Humanos , Masculino , Métodos , Persona de Mediana Edad , Transferencia de Nervios , Nervios Periféricos/trasplante , Complicaciones Posoperatorias/cirugía , Estudios Retrospectivos , Músculo Temporal/trasplante
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