Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 92
Filtrar
2.
Scand J Surg ; 109(3): 177-186, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31232190

RESUMEN

OBJECTIVES: Chronic pancreatitis produces disabling pain and loss of pancreatic endocrine/exocrine function. Almost half of the patients will need surgery during the course of the disease. Certain conditions, such as extrahepatic portal hypertension or cavernous transformation of the portal vein, can increase the risk of morbidity and mortality. These complications must be borne in mind in the design of the surgical treatment of chronic pancreatitis. This study is a systematic review on the coexistence of chronic pancreatitis and extrahepatic portal hypertension/cavernous transformation in patients undergoing pancreatic surgery. METHODS: We conducted an unlimited search updated on 10 December 2017, which yielded 535 results. We selected 11 articles. RESULTS: Main indication for surgery was intractable pain. Presence of extrahepatic portal hypertension and/or cavernous transformation increased intraoperative bleeding and general postoperative morbidity, though the increase in general morbidity was less when the different postoperative complications were analyzed individually. Case series showed a higher mortality in patients with extrahepatic portal hypertension. CONCLUSION: Little is known about the presence of extrahepatic portal hypertension in patients undergoing pancreatic surgery for chronic pancreatitis. More studies are needed in order to standardize criteria for vascular involvement in patients with chronic pancreatitis, in order to select the surgical technique and, if necessary, to establish contraindications, in this subgroup of patients.


Asunto(s)
Hipertensión Portal/etiología , Pancreatectomía , Pancreatitis Crónica/complicaciones , Pancreatitis Crónica/cirugía , Vena Porta/anomalías , Pérdida de Sangre Quirúrgica/estadística & datos numéricos , Humanos , Pancreatectomía/mortalidad , Pancreatitis Crónica/mortalidad , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Factores de Riesgo , Resultado del Tratamiento
3.
Hum Genomics ; 13(1): 3, 2019 01 10.
Artículo en Inglés | MEDLINE | ID: mdl-30630528

RESUMEN

Interpretation of variants of unknown significance (VUS) in genetic tests is complicated in ethnically diverse populations, given the lack of information regarding the common spectrum of genetic variation in clinically relevant genes. Public availability of data obtained from high-throughput genotyping and/or exome massive parallel sequencing (MPS)-based projects from several thousands of outbred samples might become useful tools to evaluate the pathogenicity of a VUS, based on its frequency in different populations. In the case of the Mexican and other Latino populations, several thousands of samples have been genotyped or sequenced during the last few years as part of different efforts to identify common variants associated to common diseases. In this report, we analyzed Mexican population data from a sample of 3985 outbred individuals, and additional 66 hereditary breast cancer patients were analyzed in order to better define the spectrum of common genomic variation of the BRCA1 and BRCA2 genes. Our analyses identified the most common genetic variants in these clinically relevant genes as well as the presence and frequency of specific pathogenic mutations present in the Mexican population. Analysis of the 3985 population samples by MPS identified three pathogenic mutations in BRCA1, only one population sample showed a BRCA1 exon 16-17 deletion by MLPA. This resulted in a basal prevalence of deleterious mutations of 0.10% (1:996) for BRCA1 and 11 pathogenic mutations in BRCA2, resulting in a basal prevalence of deleterious mutations of 0.276% (1:362) for BRCA2, combined of 0.376% (1:265). Separate analysis of the breast cancer patients identified the presence of pathogenic mutations in 18% (12 pathogenic mutations in 66 patients) of the samples by MPS and 13 additional alterations by MLPA. These results will support a better interpretation of clinical studies focused on the detection of BRCA mutations in Mexican and Latino populations and will help to define the general prevalence of deleterious mutations within these populations.


Asunto(s)
Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias de la Mama/genética , Mutación , Femenino , Genética de Población , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , México , Tasa de Mutación
5.
J Opt Soc Am A Opt Image Sci Vis ; 31(7): 1588-94, 2014 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-25121447

RESUMEN

We theoretically studied the influence of an infinite set of waveguides on the evanescent field of Bloch waves at the surface of a one-dimensional photonic crystal (PC) excited by a TE Gaussian beam undergoing total internal reflection. The set of waveguides is regarded as a periodic inhomogeneous medium with period a. Numerical results are presented for the case in which a is greater than λ, which is the wavelength used to excite the surface mode. When the waveguide tip is very close to the surface of the PC, a fraction of the surface wave is reflected by the tip, producing an interference pattern that can be observed in the near field. In this case, the system simulates scanning tunneling optical microscopy in 2D geometry, and an image of the field distribution of the surface mode is obtained by quantifying the flux energy throughout the waveguide.

10.
Obes Surg ; 19(8): 1150-8, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19455372

RESUMEN

BACKGROUND: Although bariatric surgery is currently the most common practice for inducing weight loss in morbidly obese patients (BMI>40 kg/m2), its effect on the lipid content of adipose tissue and its lipases (lipoprotein lipase [LPL] and hormone-sensitive lipase [HSL]) are controversial. METHODS: We analyzed LPL and HSL activities and lipid content from plasma as well as subcutaneous (SAT) and visceral (VAT) adipose tissue of 34 morbidly obese patients (MO) before and after (6 and 12 months) Roux-en-Y gastric bypass surgery and compare the values with those of normal weight (control) patients. RESULTS: LPL activity was significantly higher in MO (SAT=32.9+/-1.0 vs VAT=36.4+/-3.3 mU/g tissue; p<0.001) than in control subjects (SAT=8.2+/-1.4 vs VAT=6.8+/-1.0 mU/g tissue) in both adipose depots. HSL activity had similar values in both types of tissue (SAT=32.8+/-1.6 and VAT=32.9+/-1.6 mU/g) of MO. In the control group, we found similar results but with lower values (SAT=11.9+/-1.4 vs VAT=12.1+/-1.4 mU/g tissue). Twelve months after surgery, SAT LPL activity diminished (9.8+/-1.4 mU/g tissue, p<0.001 vs morbidly obese), while HSL (46.6+/-3.7 mU/g tissue) remained high. All lipids in tissue and plasma diminished after bariatric surgery except plasma nonesterified fatty acids, which maintained higher levels than controls (16+/-3 vs 9+/-0 mg/dL; p<0.001, respectively). CONCLUSIONS: When obese patients lose weight, they lose not only part of the lipid content of the cells but also the capacity to store triacylglycerides in SAT depots.


Asunto(s)
Derivación Gástrica , Lipoproteína Lipasa/sangre , Obesidad Mórbida/cirugía , Esterol Esterasa/sangre , Pérdida de Peso , Adulto , Estudios de Casos y Controles , Femenino , Estudios de Seguimiento , Humanos , Grasa Intraabdominal/metabolismo , Grasa Intraabdominal/patología , Metabolismo de los Lípidos , Masculino , Persona de Mediana Edad , Obesidad Mórbida/fisiopatología , Grasa Subcutánea/metabolismo , Grasa Subcutánea/patología , Resultado del Tratamiento
11.
Caries Res ; 43(2): 137-41, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19321992

RESUMEN

The objective of this in vivo study was to evaluate the performance of a laser fluorescence device in detecting dentinal caries in noncavitated occlusal surfaces. The sample included 102 first and second permanent molars, selected according to the criteria of Ekstrand et al. [Caries Res 1997;31:224-231]: 46 not suspected of having dentinal caries (score: 0-2) and 56 under suspicion (score: 3-4). Once measured by laser fluorescence, all were validated by fissurotomy (gold standard). To avoid ethical questions, the 46 teeth (score: 0-2) used were to serve as abutments for a fixed-fixed bridge. Visual inspection performed well, showing a sensitivity and specificity of 0.93 and 0.88, respectively. Laser fluorescence had an area under the receiver operating characteristic curve of A(z) = 0.85. The cutoff point with the highest sensitivity and specificity was 20, with a sensitivity and specificity of 0.89 and 0.75, respectively.


Asunto(s)
Caries Dental/diagnóstico , Dentina/patología , Rayos Láser , Diente Molar/patología , Corona del Diente/patología , Adulto , Área Bajo la Curva , Biopsia , Esmalte Dental/patología , Fisuras Dentales/diagnóstico , Diagnóstico Diferencial , Fluorescencia , Dureza , Humanos , Curva ROC , Sensibilidad y Especificidad , Decoloración de Dientes/diagnóstico , Adulto Joven
12.
Obes Surg ; 19(10): 1414-23, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19172368

RESUMEN

BACKGROUND: Although bariatric surgery is the most common procedure used to induce weight loss in morbidly obese patients, its effect on plasma satiety factors (leptin, ghrelin, and apolipoprotein (apo)-AIV) is controversial. The aim of this work was to analyze these parameters before and at different times after surgery. METHODS: Plasma was obtained from 34 patients before undergoing Roux-en-Y gastric bypass and during weight loss in the 12 months following surgery. RESULTS: Morbidly obese patients had significantly higher values (147%) of leptin than normal-weight (NW) persons, while their ghrelin levels were 46% less than NW. Apo-AIV levels had approximately the same value in both groups (obese and NW). During weight loss, leptin decreased by 75% and ghrelin increased by 78%. Both parameters reached values less than or near NW, respectively, at 1 year after surgery. During the first month after surgery, apo-AIV plasma levels decreased (47%) but later increased and finally returned to preoperative values. Apo-AIV levels were correlated negatively with leptin and positively with ghrelin. High-density lipoprotein (HDL) levels were positively correlated with those of ghrelin and apo-AIV. CONCLUSIONS: During weight loss, plasma leptin and ghrelin could be good markers of total fat decrease. Ghrelin could also indicate gastric mucous improvement, whereas apo-AIV could indicate the recovery of intestinal function. Changes produced in the HDL levels of morbidly obese patients during weight loss suggest a decreased risk of coronary disease.


Asunto(s)
Apolipoproteínas A/sangre , Ghrelina/sangre , Leptina/sangre , Obesidad Mórbida/sangre , Pérdida de Peso/fisiología , Tejido Adiposo/metabolismo , Adulto , Biomarcadores/sangre , Femenino , Derivación Gástrica , Humanos , Insulina/sangre , Metabolismo de los Lípidos , Masculino , Persona de Mediana Edad , Obesidad Mórbida/cirugía , Saciedad/fisiología , Delgadez/sangre , Factores de Tiempo
14.
Acta Otorrinolaringol Esp ; 57(9): 429-31, 2006 Nov.
Artículo en Español | MEDLINE | ID: mdl-17184013

RESUMEN

Cysts with an origin in a malignant tumour of the cervical region are rare. It is even more uncommon that the malignant tumour has its origin in a minor salivary gland as it is the malignant transformation of a pleomorphic adenoma. Some considerations are made regarding its localization, histopathology, diagnosis and therapeuthic attitude, as well as some advices to take into account in order to arrive to the diagnosis and correct treatment in similar cases to the one shown.


Asunto(s)
Adenocarcinoma/patología , Adenoma Pleomórfico/patología , Neoplasias de Cabeza y Cuello/patología , Neoplasias de las Glándulas Salivales/patología , Glándulas Salivales Menores/patología , Adenocarcinoma/cirugía , Adenoma Pleomórfico/cirugía , Anciano , Neoplasias de Cabeza y Cuello/cirugía , Humanos , Masculino , Neoplasias de las Glándulas Salivales/cirugía , Glándulas Salivales Menores/cirugía
15.
Appl Opt ; 39(25): 4698-705, 2000 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-18350061

RESUMEN

Scattering of s-polarized electromagnetic planes waves from a film, with a shallow random rough one-dimensional surface, bounded by vacuum and a perfect conductor is calculated. An integral equation that relates the amplitude of the scattered field to the incident wave is found by use of the Rayleigh hypothesis. The integral equation is solved numerically and by use of the perturbation theory, up to the fourth order in the surface profile function. In the angular dependence of the incoherent part of the differential reflection coefficient, the backscattering peak and two additional satellite peaks are observed, owing to two guided waves supported by the film. Analysis of the perturbation solution reveals that the background scattering exhibits minima and maxima as functions of the thickness. By studying the behavior of the scattering as a function of the absorption index of the film, it is shown that the amplitudes of the peaks are low when k approximately 10(-2) and high when k approximately 10(-4).

16.
Chest ; 112(6): 1711, 1997 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9404784
17.
Endod Dent Traumatol ; 13(4): 196-8, 1997 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9550048

RESUMEN

Dens invaginatus is a developmental variation resulting from an alteration in the normal growth pattern of the dental papilla of a tooth. This anomaly occurs predominantly in maxillary permanent lateral incisors. Multiple occurrence in maxillary incisor teeth in the same patient has frequently been reported, and examination of bilateral teeth for the anomaly is often carried out routinely. This paper reports an unusual case of multiple invaginations, including dens invaginatus affecting maxillary lateral incisors and a supernumerary tooth and minor invaginations of the upper canines. Moreover, the case illustrates the importance of examining all the teeth in patients who present with dens invaginatus and palatal pits in incisors and canines. The possibility that the supernumerary tooth had resulted from gemination of the lateral incisor tooth germ is discussed.


Asunto(s)
Dens in Dente , Incisivo/anomalías , Diente Supernumerario , Dens in Dente/complicaciones , Dens in Dente/patología , Humanos , Masculino , Maxilar , Persona de Mediana Edad , Diente Supernumerario/etiología
18.
J Endod ; 23(7): 444-7, 1997 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9587299

RESUMEN

The purpose of this study was to investigate the effect of calcium hydroxide on substrate adherence capacity of rat inflammatory macrophages to determine if calcium hydroxide can alter macrophage function. Inflammatory macrophages were obtained from Wistar rats and resuspended in RPMI-1640 medium. Substrate adherence capacity assays were carried out in Eppendorf tubes for 15 min of incubation at 37 degrees C in a humidified atmosphere of 5% CO2. The adherence index (AI) was calculated. Results showed that calcium hydroxide decreased substrate adherence capacity of inflammatory macrophages in a time and dose-dependent manner. The lowest calcium hydroxide concentration that caused a significant inhibition of AI was 1 mM (p < 0.05), and the concentration of calcium hydroxide that caused half-maximal inhibition (IC50) was 1.54 mM (p < 0.01). We conclude that calcium hydroxide decreased substrate adherence capacity of macrophages. When adhesion as the first step in the phagocytic process and in antigen presentation is taken into account, calcium hydroxide could inhibit macrophage function and reduce inflammatory reactions in periapical tissues or in dental pulp when it is used in root-canals therapy or in direct pulp capping and pulpotomy, respectively. Moreover, this effect could explain, at least in part, the mineralized tissue-inducing property of calcium hydroxide.


Asunto(s)
Hidróxido de Calcio/farmacología , Macrófagos Peritoneales/efectos de los fármacos , Materiales de Obturación del Conducto Radicular/farmacología , Animales , Adhesión Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Concentración de Iones de Hidrógeno , Macrófagos Peritoneales/fisiología , Masculino , Ratas , Ratas Wistar , Factores de Tiempo
19.
J Endod ; 23(4): 205-8, 1997 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9594765

RESUMEN

The disodium salt of ethylenediamine tetraacetate (EDTA) is a calcium ion chelator used in endodontics to enlarge root canals. This study investigated the effect of EDTA on substrate adherence capacity of rat inflammatory macrophages to determine if EDTA leakage to periapical tissues during root canal therapy can alter macrophage function. Inflammatory macrophages were obtained from Wistar rats and resuspended in RPMI-1640 medium. Substrate adherence capacity assays were carried out in Eppendorf tubes for 15 min of incubation at 37 degrees C in a humidified atmosphere of 5% CO2. The adherence index (AI) was calculated. Results showed that EDTA decreased substrate adherence capacity of inflammatory macrophages in a time and dose-dependent manner. The lowest EDTA concentration that caused a significant inhibition of AI was 50 mM (p < 0.05), and the EDTA concentration that caused half-maximal inhibition (IC50) was 194 +/- 20 mM (p < 0.01). Calcium chloride (10 mM) increased the adherence index of macrophages by 17.1% (p < 0.05) and decreased the EDTA inhibitory effect on AI by 49.5% (p < 0.05). We conclude that an EDTA concentration lower than that used in endodontics decreased the substrate adherence capacity of macrophages significantly. Adhesion is the first step in the phagocytic process and in antigen presentation, but leakage of EDTA to periapical tissues during root canals preparation may inhibit macrophage function and reduce periapical inflammatory reactions.


Asunto(s)
Adhesión Celular/efectos de los fármacos , Ácido Edético/farmacología , Macrófagos/fisiología , Animales , Cloruro de Calcio/farmacología , Células Cultivadas , Relación Dosis-Respuesta a Droga , Extravasación de Materiales Terapéuticos y Diagnósticos , Activación de Macrófagos/efectos de los fármacos , Masculino , Tejido Periapical/efectos de los fármacos , Fagocitosis/efectos de los fármacos , Ratas , Ratas Wistar , Preparación del Conducto Radicular , Factores de Tiempo
20.
J Endod ; 23(12): 728-30, 1997 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9487846

RESUMEN

The purpose of this study was to investigate the "in vitro" effect of parachlorophenol and camphorated parachlorophenol, used in endodontics for the disinfection of root canals, on the substrate adherence capacity of macrophages. Inflammatory macrophages were obtained from Wistar rats and resuspended in RPMI-1640 medium. As a test of macrophage phagocytic function, the adherence capacity of macrophages to a plastic surface was determined. Assays were conducted in Eppendorf tubes for 15 min of incubation at 37 degrees C in a humidified atmosphere of 5% CO2. The adherence index was calculated. Results showed that parachlorophenol and camphorated parachlorophenol significantly decreased the substrate adherence capacity of inflammatory macrophages. Taking into account that adhesion is the first step in the phagocytic process of macrophages and in antigen presentation, parachlorophenol and camphorated parachlorophenol could inhibit macrophage function and modulate immune and inflammatory reactions in periapical tissues.


Asunto(s)
Antiinfecciosos Locales/farmacología , Alcanfor/farmacología , Clorofenoles/farmacología , Macrófagos Peritoneales/efectos de los fármacos , Irrigantes del Conducto Radicular/farmacología , Animales , Adhesión Celular/efectos de los fármacos , Separación Celular/métodos , Depresión Química , Relación Dosis-Respuesta a Droga , Combinación de Medicamentos , Macrófagos Peritoneales/fisiología , Ratas , Ratas Wistar
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA