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1.
Parasitol Int ; 91: 102640, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35933034

RESUMEN

We performed a study of congenital toxoplasmosis of the first and third gestation periods in mice, and determined its effects on the embryos/fetuses, the placentae and the maternal organs. We infected pregnant BALB/c mice by i.v. injection of 2.5--10.0 × 106 tachyzoites of the ME49 T. gondii strain and euthanized them 72 h later. The tissues were analyzed by histopathology, immunohistochemistry and parasite-specific qPCR. Infections with the lowest dose induced remarkably different changes in the two thirds: a) all doses diminished the number of products/litter, the lowest dose only by 14%; but most embryos still visible were degenerated in the case of the first period, while the fetuses of the last third were perfectly preserved; b) the transmission rate in the first third was relatively high, but with a very low parasite burden; c) with the lowest dose, strong vascular changes (congestion, thrombosis and hemorrhage) predominated in the placentas of the first period, while they were absent in the last third; d) necrosis caused by T. gondii to maternal organs was much stronger during the last gestation period than in the first. Our results suggest that the vascular alterations at the placenta of the first third of pregnancy prevent embryo from large parasite burden, but provoke its death by starvation. In the last gestation period, there was poor control of parasite dissemination to the placenta and the fetus, but there was greater capacity of the product to defend itself from T. gondii.


Asunto(s)
Toxoplasma , Toxoplasmosis Congénita , Animales , Modelos Animales de Enfermedad , Femenino , Humanos , Ratones , Ratones Endogámicos BALB C , Madres , Placenta/parasitología , Embarazo , Toxoplasmosis Congénita/parasitología
2.
J Biol Regul Homeost Agents ; 32(3): 479-487, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29921372

RESUMEN

Alterations in cellular and extracellular matrix components play an important role during tumorigenesis; proteoglycans are included among these components. Ameloblastomas are odontogenic tumors distinguished as invasive and infiltrative neoplasms and are divided into different histological types, the most common of which are the unicystic ameloblastoma and the conventional ameloblastoma. The aim of this study was to identify the presence of two proteoglycans, perlecan and biglycan, in different types of ameloblastoma. Using immunohistochemistry, we determined the presence of both proteins in 28 unicystic ameloblastomas and 23 conventional ameloblastomas. We identified the cytoplasmic and nuclear presence of perlecan and the cytoplasmic presence of biglycan in both types of ameloblastoma. The mean values of immunoexpression were higher in the conventional type compared to the unicystic type. Neither the presence of biglycan in ameloblastomas nor the nuclear presence of perlecan in any odontogenic tumor has previously been reported. The differential immunoexpression of perlecan and biglycan in these types of ameloblastomas suggests their participation in the developmental process of these tumors.


Asunto(s)
Ameloblastoma , Biglicano/biosíntesis , Regulación Neoplásica de la Expresión Génica , Proteoglicanos de Heparán Sulfato/biosíntesis , Neoplasias Maxilomandibulares , Proteínas de Neoplasias/biosíntesis , Adulto , Ameloblastoma/clasificación , Ameloblastoma/metabolismo , Ameloblastoma/patología , Femenino , Humanos , Inmunohistoquímica , Neoplasias Maxilomandibulares/clasificación , Neoplasias Maxilomandibulares/metabolismo , Neoplasias Maxilomandibulares/patología , Masculino
3.
Phys Rev Lett ; 120(8): 083603, 2018 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-29543025

RESUMEN

Superradiance in an ensemble of atoms leads to the collective enhancement of radiation in a particular mode shared by the atoms in their spontaneous decay from an excited state. The quantum aspects of this phenomenon are highlighted when such collective enhancement is observed in the emission of a single quantum of light. Here we report a further step in exploring experimentally the nonclassical features of superradiance by implementing the process not only with single excitations, but also in a two-excitation state. Particularly, we measure and theoretically model the wave packets corresponding to superradiance in both the single-photon and two-photon regimes. Such progress opens the way to the study and future control of the interaction of nonclassical light modes with collective quantum memories at higher photon numbers.

4.
Oral Oncol ; 44(8): 805-11, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18207448

RESUMEN

Ameloblastoma is the most frequent odontogenic tumor and is considered a benign, but locally invasive, neoplasm with variable clinico-pathological expression. Syndecan-1 is a cell surface proteoglycan that binds cells to the extracellular matrix and its expression is down-regulated in many cellular transformation models. The aims of this study were to examine the pattern of syndecan-1 expression, to evaluate the proliferating activity in a large series of solid/multicystic (SA) and unicystic ameloblastomas (UA), and to study its possible correlation to their biological behavior. Immunohistochemical studies were performed for syndecan-1 (clone MI15) and Ki-67 (clone MIB-1) in 120 ameloblastomas (75 SA and 45 UA). The salient finding was that expression of syndecan-1 was related to the histological subtype of tumors, as there was a lower expression in SA (40.2%) as compared to UA (49.7%) (p<0.05). These findings did not correlate with Ki-67 expression, as this was similar in both types of ameloblastomas. Our results suggest that the reduced expression of syndecan-1 supports the view that SA has a more aggressive biological behavior than the UA. The lack of correlation between reduction of the syndecan-1 and Ki-67 index may be due to the different histomorphologies of both types of ameloblastoma, and more studies are necessary to better understand the role of this protein in the biological behavior of these tumors.


Asunto(s)
Ameloblastoma/metabolismo , Antígeno Ki-67/metabolismo , Proteínas de Neoplasias/metabolismo , Sindecano-1/metabolismo , Adolescente , Adulto , Anciano , Niño , Preescolar , Regulación hacia Abajo , Femenino , Expresión Génica , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Mucosa Bucal/metabolismo , Germen Dentario/metabolismo , Adulto Joven
5.
Rev Alerg Mex ; 45(3): 17-21, 1998.
Artículo en Español | MEDLINE | ID: mdl-9718975

RESUMEN

AIMS: A prospective, observational clinical trial is presented with the object of determining the frequency with which CT scans of the paranasal sinuses establish the diagnosis of chronic sinusitis in patients with symptoms of sinusitis but without alterations in the plain films of the paranasal sinuses. MATERIAL AND METHODS: The study included 113 patients, 64 females and 49 males, with the clinical diagnosis of chronic sinusitis. All had plain films of the paranasal sinuses. CT scans of the paranasal sinuses were performed on all patients with negative findings on plane films. RESULTS: Of the 113 patients, 68 (60%) presented positive radiographic findings of chronic sinusitis on plain films. In the 45 remaining patients (39%) in which plain films were negative, CT scans of the paranasal sinuses were performed and demonstrated ethmoid sinusitis in all of them (100%). CONCLUSION: That CT scan is more sensitive in the diagnosis of ethmoid sinusitis as compared to plain films of the paranasal sinuses, due to the fact that ethmoid anatomy is better delineated by this method. Plain films of the paranasal sinuses are of lesser use in determining ethmoid anatomy due to the superposition of images that occurs in this technique.


Asunto(s)
Senos Paranasales/diagnóstico por imagen , Sinusitis/diagnóstico por imagen , Enfermedad Crónica , Femenino , Humanos , Masculino , Valor Predictivo de las Pruebas , Estudios Prospectivos , Tomografía Computarizada por Rayos X
6.
Rev Alerg Mex ; 45(1): 16-21, 1998.
Artículo en Español | MEDLINE | ID: mdl-9608781

RESUMEN

OBJECTIVE: In order to explore the association between poorly controllable asthma and gastroesophageal reflux (GER), a prospective clinical trial is presented. MATERIAL AND METHOD: This trial included 28 patients with negative atopic indicators who presented difficulty in the management of their disease. All patients underwent a complete medical history as well as skin tests for common airborne allergens, total serum IgE, peripheral blood eosinophils, spirometry, chest X-ray and esophageal barium films. Additionally, esophageal endoscopy was performed on 9 patients, and esophageal manometry in 1 patient. All were submitted to antireflux therapy and received omeprazole and cisapride for 8 weeks. RESULTS: Complete improvement was observed in 24 patients (85.7%), moderate improvement in 3 patients (10.7%), and no improvement in 1 patient (3.6%). Three patients required antireflux surgery. CONCLUSIONS: Symptoms reappeared 2-3 weeks after suspending treatment, which led to the recommendation that antireflux measures become a way of life for these patients.


Asunto(s)
Asma/etiología , Inhibidores Enzimáticos/uso terapéutico , Reflujo Gastroesofágico/complicaciones , Fármacos Gastrointestinales/uso terapéutico , Omeprazol/uso terapéutico , Piperidinas/uso terapéutico , Adolescente , Adulto , Anciano , Asma/prevención & control , Cisaprida , Terapia Combinada , Esofagoscopía , Femenino , Volumen Espiratorio Forzado , Reflujo Gastroesofágico/tratamiento farmacológico , Reflujo Gastroesofágico/cirugía , Hernia Hiatal/complicaciones , Hernia Hiatal/cirugía , Humanos , Inmunoglobulina E/sangre , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Inducción de Remisión , Pruebas Cutáneas , Resultado del Tratamiento
7.
Rev Alerg Mex (1987) ; 37(4): 123-6, 1990.
Artículo en Español | MEDLINE | ID: mdl-2089602

RESUMEN

We compared swab and scraping (Rhino-probe) technics in the nasal cytology obtention for eosinophils count in 36 patients with a range of 2-46 years old (mean age 18.6 years) with diagnosis of Allergic Rhinitis. The eosinophil count with swab technic was between 0-79 cells with average of 6.5 cells and in the scraping (Rhino-probe) was in a rate of 0-100 cells with a average of 13.4 cells. Of the 36 patients with Rhinitis seen at our clinic, 13 (36%) of positive with swab and 19 (53%) with scraping technics (Rhino-probe) with percent differential of 17%. The comparison between the eosinophils count with both technics was p less than 0.05 for scraping (Rhino-probe) technic.


Asunto(s)
Eosinófilos , Recuento de Leucocitos/métodos , Moco/citología , Rinitis Alérgica Perenne/patología , Adolescente , Adulto , Niño , Preescolar , Femenino , Humanos , Recuento de Leucocitos/instrumentación , Masculino , Persona de Mediana Edad , Mucosa Nasal/patología , Rinitis Alérgica Perenne/inmunología , Manejo de Especímenes
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