Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 53
Filtrar
Más filtros

País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Cir Pediatr ; 30(3): 146-151, 2017 Jul 20.
Artículo en Español | MEDLINE | ID: mdl-29043692

RESUMEN

PURPOUSE: The aim of this study is to assess the diagnostic accuracy of ultrasound to differentiate appendicitis from nonspecific acute abdominal pain, that is the most common process requiring differential diagnosis in clinical practice. MATERIAL AND METHODS: Patients admitted for suspicion of appendicitis were prospectively evaluated in our hospital during two years (2013-2014). Cases of nonspecific acute abdominal pain and appendicitis assessed by ultrasound were enrolled in the study. The different variables collected were statistically analyzed by descriptive, univariate and diagnostic accuracy studies. RESULTS: A total of 275 patients were studied, 143 cases of nonspecific acute abdominal pain and 132 cases of appendicitis. Ultrasound sensitivity and specificity to differentiate appendicitis were 94.7% and 87.4% respectively, with a 12.6% rate of false positives and a 5.3% rate of false negatives. The rate of false negatives in perforated group was 17.4% and analysis according to Pediatric Appendicitis Score risk groups showed a 12.2% rate of false positives in low-risk group and a 6.3% rate of false negatives in high-risk group. CONCLUSIONS: The use of ultrasound in low clinical probability cases of appendicitis could rise unnecessary surgery rate, due to the significant number of false positives in this group of patients. In high probability clinical cases, ultrasound does not contribute too much to diagnosis and it could be a confusion factor by the significant number of false negative associated to perforated appendicitis.


OBJETIVO: El objetivo del estudio es evaluar el rendimiento diagnóstico de la ecografía para diferenciar la apendicitis del dolor abdominal agudo inespecífico, principal proceso con el que requiere diagnóstico diferencial en la práctica clínica. MATERIAL Y METODOS: Se evaluaron los pacientes atendidos por sospecha de apendicitis en nuestro centro durante 2 años (2013-2014), incorporando al estudio los casos de dolor abdominal agudo inespecífico y apendicitis en los que se realizó ecografía. Las diferentes variables recogidas se analizaron estadísticamente de manera descriptiva, univariante y con estudios de rendimiento diagnóstico. RESULTADOS: Se estudiaron 275 casos; 143 casos de dolor abdominal agudo inespecífico y 132 casos de apendicitis. La sensibilidad y especificidad de la ecografía para diferenciar apendicitis fue del 94,7% y 87,4%, respectivamente, con un porcentaje de falsos positivos del 12,6% y de falsos negativos del 5,3%. El porcentaje de falsos negativos en el grupo de apendicitis perforada alcanzó el 17,4% y el análisis según los grupos de riesgo establecidos por el Pediatric Appendicitis Score mostró un porcentaje de falsos positivos del 12,2% en el grupo de bajo riesgo y de falsos negativos del 6,3% en el grupo de alto riesgo. CONCLUSIONES: El uso de la ecografía en casos de baja probabilidad clínica de apendicitis podría incrementar la tasa de cirugía innecesaria, debido al significativo número de falsos positivos en este grupo de pacientes. En casos de alta probabilidad clínica de apendicitis, la ecografía aporta poco al diagnóstico, e incluso podría ser un factor de confusión por el significativo número de falsos negativos asociados a la apendicitis perforada.


Asunto(s)
Dolor Abdominal/diagnóstico por imagen , Dolor Agudo/diagnóstico por imagen , Apendicitis/diagnóstico por imagen , Ultrasonografía/métodos , Niño , Diagnóstico Diferencial , Reacciones Falso Negativas , Reacciones Falso Positivas , Femenino , Humanos , Masculino , Estudios Prospectivos , Factores de Riesgo , Sensibilidad y Especificidad
2.
Reprod Domest Anim ; 51(1): 123-9, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26661993

RESUMEN

With the development of the non-surgical deep uterine (NsDU) embryo transfer (ET) technology, the commercial applicability of ET in pigs is now possible. There are, nevertheless, many factors that influence NsDU-ET effectiveness that need to be addressed. The aim of this study was to evaluate the effects of the weaned recipients' parity on fertility and prolificacy following NsDU-ET. The recipients (n = 120) were selected based on their reproductive history and body condition and grouped into three categories according to their parity: primiparous sows, sows of parity 2 and sows of parities from 3 to 5. Thirty fresh embryos (morulae and unhatched blastocysts) were non-surgically transferred into one uterine horn of each recipient. It was possible to insert the NsDU-ET catheter through the cervix along a uterine horn in 98.3% of the recipients. The parity had no influence on the difficulty grade of the insertions or on the percentage of correct insertions. The cervix and uterine wall were not perforated during the insertions, and vaginal discharge was not observed after transfer in any of the recipients. There were no differences in the pregnancy rates (74.8%), farrowing rates (71.2%) or litter sizes (9.6 ± 3.3) between groups. Also, there were no differences between groups regarding to the piglets' birthweights or piglet production efficiency. In conclusion, these results demonstrate that weaned sows from parity 1 to 5 are appropriate to be used as recipients in NsDU-ET programs, which increase the possibilities for the utilization of ET in the recipient farms.


Asunto(s)
Transferencia de Embrión/veterinaria , Paridad/fisiología , Reproducción/fisiología , Sus scrofa/fisiología , Útero , Animales , Peso al Nacer , Transferencia de Embrión/métodos , Femenino , Fertilidad , Embarazo , Destete
3.
Proc Natl Acad Sci U S A ; 107(38): 16459-64, 2010 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-20823259

RESUMEN

The goal of this paper is to state the optimal decay rate for solutions of the nonlinear fast diffusion equation and, in self-similar variables, the optimal convergence rates to Barenblatt self-similar profiles and their generalizations. It relies on the identification of the optimal constants in some related Hardy-Poincaré inequalities and concludes a long series of papers devoted to generalized entropies, functional inequalities, and rates for nonlinear diffusion equations.

4.
Exp Neurol ; 370: 114581, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37884190

RESUMEN

Dravet syndrome is a rare form of severe genetic epilepsy characterized by recurrent and long-lasting seizures. It appears around the first year of life, with a quick evolution toward an increase in the frequency of the seizures, accompanied by a delay in motor and cognitive development, and does not respond well to antiepileptic medication. Most patients carry a mutation in the gene SCN1A encoding the α subunit of the voltage-gated sodium channel Nav1.1, resulting in hyperexcitability of neural circuits and seizure onset. In this work, we applied transcranial static magnetic stimulation (tSMS), a non-invasive, safe, easy-to-use and affordable neuromodulatory tool that reduces neural excitability in a mouse model of Dravet syndrome. We demonstrate that tSMS dramatically reduced the number of crises. Furthermore, crises recorded in the presence of the tSMS were shorter and less intense than in the sham condition. Since tSMS has demonstrated its efficacy at reducing cortical excitability in humans without showing unwanted side effects, in an attempt to anticipate a possible use of tSMS for Dravet Syndrome patients, we performed a numerical simulation in which the magnetic field generated by the magnet was modeled to estimate the magnetic field intensity reached in the cerebral cortex, which could help to design stimulation strategies in these patients. Our results provide a proof of concept for nonpharmacological treatment of Dravet syndrome, which opens the door to the design of new protocols for treatment.


Asunto(s)
Epilepsias Mioclónicas , Canal de Sodio Activado por Voltaje NAV1.1 , Animales , Ratones , Humanos , Canal de Sodio Activado por Voltaje NAV1.1/genética , Epilepsias Mioclónicas/genética , Epilepsias Mioclónicas/terapia , Convulsiones/terapia , Convulsiones/genética , Estimulación Magnética Transcraneal , Modelos Animales de Enfermedad , Fenómenos Magnéticos
5.
Theriogenology ; 71(1): 80-8, 2009 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-18977521

RESUMEN

Several hundred thousand offspring of preselected sex of various species have been born since sperm sexing technology based on flow cytometric sorting of X- and Y-chromosome-bearing sperm and DNA was first demonstrated in 1989. The advantages derived from application of sexing technology to commercial dairy cattle production have been demonstrated worldwide. Utilizing sex-sorting technology for pig production systems offers many similar advantages. However, several factors currently limit implementation of sexing technology in pigs. Anatomical and physiological features inherent to the female pig, together with the relatively low sperm output of a flow sorter, are the main limitations to widespread use of this technology in pig production systems. This review analyzes the factors that limit the efficiency of sperm sorting technology for commercial swine production. In addition, this review discusses recent innovations in technical instrumentation and applied reproductive techniques that may help to overcome some of these limitations.


Asunto(s)
Citometría de Flujo/veterinaria , Preselección del Sexo/veterinaria , Espermatozoides/fisiología , Animales , Femenino , Inseminación Artificial/veterinaria , Masculino , Embarazo , Porcinos
6.
Theriogenology ; 70(8): 1216-24, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18674810

RESUMEN

New nonsurgical procedures for inseminating swine with a low number of spermatozoa have been developed and/or evaluated over the last few years. These procedures allow the deposition of the insemination dose into the uterine body (post-cervical insemination) or directly into the uterine horn (deep intrauterine insemination). With the use of the post-cervical insemination, a threefold reduction in the number of fresh sperm has been successfully used to achieve pregnancy. Using deep intrauterine insemination (DUI), up to a 20-fold reduction in the number of fresh spermatozoa or a sixfold reduction in the number of frozen/thawed spermatozoa can be achieved, with reproductive performance very similar to that obtained after standard AI. Complementing these nonsurgical insemination techniques, a new procedure for depositing spermatozoa into the oviduct by laparoscopy has been recently described. This laparoscopic technique has proven to be applicable to diluted and sex-sorted spermatozoa. The development of new insemination procedures will help achieve more efficient application of currently available sperm technologies. Using appropriate insemination procedures, it is now feasible to achieve high fertility rates with cooled, frozen-thawed, or sex-sorted semen.


Asunto(s)
Inseminación Artificial/veterinaria , Porcinos/fisiología , Crianza de Animales Domésticos , Animales , Femenino , Inseminación Artificial/métodos , Masculino , Embarazo , Espermatozoides/fisiología
7.
Reprod Domest Anim ; 43 Suppl 2: 347-54, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18638145

RESUMEN

Low-dose AI procedures are required by the pig industry to efficiently utilize emerging sperm technologies, such as cryopreservation and sex-sorting. Currently, several different procedures for inseminating with a low or very low number of spermatozoa have been described. Deep intrauterine insemination allows the deposition of the spermatozoa in the depth of the uterine horn, allowing a significant reduction in the number of spermatozoa inseminated with maintenance of optimal reproductive performance. Intra-oviductal laparoscopic insemination has been recently applied in pigs. This technique has proved to be applicable with diluted and sex-sorted spermatozoa. This review discusses several problems encountered during the development of deep intrauterine insemination and intra-oviductal laparoscopic insemination of pigs and provides potential solutions for the practical application of both the technologies.


Asunto(s)
Inseminación Artificial/veterinaria , Preservación de Semen/veterinaria , Preselección del Sexo/veterinaria , Recuento de Espermatozoides/veterinaria , Espermatozoides/fisiología , Porcinos/fisiología , Animales , Criopreservación/veterinaria , Femenino , Histeroscopía/métodos , Histeroscopía/veterinaria , Inseminación Artificial/instrumentación , Inseminación Artificial/métodos , Masculino , Embarazo , Preservación de Semen/métodos , Preselección del Sexo/métodos , Útero
8.
Reprod Domest Anim ; 43 Suppl 4: 1-8, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18803751

RESUMEN

The sorting of X- and Y-chromosome-bearing spermatozoa by flow cytometry is nowadays one of the most apt assisted-reproduction technologies in livestock production. Potential economic and biological benefits, as well as those related to easier management of herds, have been reported arising out of the application of this technique, especially in cattle. Yet, the sex-sorting procedure induces damage to spermatozoa, affecting their function and fertilizing ability. Different species present varying degrees of susceptibility to damage from the sorting process and each has its own requirements for sex-sorted insemination procedures. Thus, several new protocols and strategies have been designed for the handling of sorted spermatozoa, with the main objective of optimizing their fertilizing ability and the consequent application of flow-cytometric sex-sorting technology. This article reviews current advances in this technology, pointing out the components to be improved before this technology may be widely applied in different domestic species.


Asunto(s)
ADN/análisis , Inseminación Artificial/veterinaria , Análisis para Determinación del Sexo/veterinaria , Preselección del Sexo/veterinaria , Espermatozoides/fisiología , Animales , Femenino , Citometría de Flujo/métodos , Citometría de Flujo/veterinaria , Inseminación Artificial/métodos , Masculino , Análisis para Determinación del Sexo/métodos , Preselección del Sexo/métodos , Especificidad de la Especie
9.
Hear Res ; 229(1-2): 171-9, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17317055

RESUMEN

Theories of temporal coding by cortical neurons are supported by observations that individual neurons can respond to sensory stimulation with millisecond precision and that activity in large populations is often highly correlated. Synchronization is highest between neurons with overlapping receptive fields and modulated by both sensory stimulation and behavioral state. It is not yet clear whether cortical synchronization is an epiphenomenon or a critical component of efficient information transmission. Experimental manipulations that generate receptive field plasticity can be used to test the relationship between synchronization and receptive fields. Here we demonstrate that increasing receptive field size in primary auditory cortex by repeatedly pairing a train of tones with nucleus basalis (NB) stimulation increases synchronization, and decreasing receptive field size by pairing different tone frequencies with NB stimulation decreases synchronization. These observations seem to support the conclusion that neural synchronization is simply an artifact caused by common inputs. However, pairing tone trains of different carrier frequencies with NB stimulation increases receptive field size without increasing synchronization, and environmental enrichment increases synchronization without increasing receptive field size. The observation that receptive fields and synchronization can be manipulated independently suggests that common inputs are only one of many factors shaping the strength and temporal precision of cortical synchronization and supports the hypothesis that precise neural synchronization contributes to sensory information processing.


Asunto(s)
Corteza Auditiva/fisiología , Estimulación Acústica , Animales , Núcleo Basal de Meynert/fisiología , Sincronización Cortical , Estimulación Eléctrica , Femenino , Microelectrodos , Plasticidad Neuronal , Ratas , Ratas Sprague-Dawley
10.
World J Gastroenterol ; 13(46): 6213-8, 2007 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-18069762

RESUMEN

AIM: To identify the anthropometric, metabolic and mood state in hepatitis C virus (HCV)-infected patients from the west of Mexico and to evaluate the effect of Breathwalk (BW), a combination of walking, synchronized breathing and focussed attention, on those patients. METHODS: In an experimental study, 17 patients with serological and molecular diagnosis of HCV, not receiving pharmacological treatment, were studied. One hour sessions of BW were practiced 3 times at week for six months. Body composition was assessed by electric impedance. Biochemical profiles and insulin resistance (IR) risk was assessed by conventional methods. Mood state was evaluated with specific and open questions at the beginning and at the end of the program. RESULTS: Seventy percent of patients were overweight or obese, and 77% of the patients presented with IR at the beginning of the study. Improvements were observed at the 3rd mo, and statistically significant differences were recorded at the 6th mo using the fitness score (76 vs 83, P < 0.01), in alanine aminotransferase (ALT) (106 +/- 93 U/L vs 59 +/- 32 U/L, P < 0.01), total bilirubin (0.09 +/- 1 mg/dL vs 0.62 +/- 0.2 mg/dL, P < 0.01), ALT/AST ratio (1.04 vs 0.70, P < 0.01), triglycerides (165 +/- 86 mg/dL vs 124 +/- 49 mg/dL, P < 0.01) and the IR risk (4.0 vs 2.7). Most patients (88%) indicated to feel better at the end of BW (P < 0.01). CONCLUSION: Breathwalk has an important effect on body composition, lipid profile and liver enzymes. It is also easy, inexpensive and has a beneficial effect on metabolic and mood state in HCV patients.


Asunto(s)
Afecto/fisiología , Composición Corporal/fisiología , Metabolismo Energético/fisiología , Terapia por Ejercicio/métodos , Hepatitis C Crónica/fisiopatología , Hepatitis C Crónica/psicología , Resistencia a la Insulina/fisiología , Adulto , Alanina Transaminasa/metabolismo , Aspartato Aminotransferasas/metabolismo , Atención/fisiología , Ejercicios Respiratorios , Femenino , Hepatitis C Crónica/terapia , Humanos , Lípidos/sangre , Hígado/enzimología , Hígado/fisiopatología , Masculino , Persona de Mediana Edad , Obesidad/sangre , Obesidad/fisiopatología , Obesidad/psicología , Caminata/fisiología
11.
Theriogenology ; 68(5): 771-8, 2007 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-17662382

RESUMEN

The sex sorting of spermatozoa by flow cytometry induces damage, since sperm cells are highly diluted, affecting their functionality and fertilizing ability. In this work it was investigated whether the concentration of sex sorted spermatozoa by the sedimentation method, rather than centrifugation, in combination with the presence of the seminal plasma protein PSP-I/PSP-II heterodimer may improve their fertilizing ability. Spermatozoa were sorted by flow cytometry and collected in BTS with 10% of seminal plasma (group C: control) or with 1.5mg/mL of PSP-I/PSP-II heterodimer (group H). Collected spermatozoa from each medium were split into two aliquots. One aliquot of each group was centrifuged (800 x g/5 min) just after sorting and stored 16-18 h at 17 degrees C (groups Cc and Hc) at 6 x 10(6)sperm/mL. The second aliquot was directly stored at 17 degrees C for 16-18 degrees C (group Cs and Hs). After storage the supernatant was discarded and the sedimented pellet adjusted to 6 x 10(6)sperm/mL. Membrane integrity, acrosome status and motility characteristics of spermatozoa from all groups were assessed. Post-weaning pre-ovulatory sows were inseminated by laparoscopy into the oviduct with 0.3 x 10(6) sex sorted spermatozoa to assess their ability to penetrate oocytes in vivo. Putative zygotes were collected 18 h after insemination by washing the oviduct. Penetration and monospermic rates were evaluated. After 16-18 h of storage, centrifuged spermatozoa collected with 10% seminal plasma or 1.5 mg/mL PSP-I/PSP-II heterodimer after sex sorting showed lower (p<0.05) percentages of membrane integrity, motility and fertilization than sedimented spermatozoa. Overall, the presence of 10% seminal plasma or PSP-I/PSP-II heterodimer did not affect the results. However, a positive effect of PSP-I/PSP-II heterodimer (p<0.05) was observed in sedimented spermatozoa. Hence, our results indicate that the sedimentation method in the presence of PSP-I/PSP-II heterodimer improves the in vivo fertilizing ability of sex sorted boar spermatozoa.


Asunto(s)
Separación Celular/métodos , Eficiencia , Fertilización/fisiología , Preñez , Espermatozoides/citología , Sus scrofa , Animales , Precipitación Química , Dimerización , Embrión de Mamíferos/citología , Femenino , Fertilización/efectos de los fármacos , Citometría de Flujo , Inseminación Artificial/veterinaria , Masculino , Embarazo , Proteínas de Secreción de la Vesícula Seminal/metabolismo , Proteínas de Secreción de la Vesícula Seminal/farmacología , Factores Sexuales , Recuento de Espermatozoides , Espermatozoides/efectos de los fármacos
12.
Theriogenology ; 87: 316-320, 2017 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-27707545

RESUMEN

Recent advances in nonsurgical deep uterine (NsDU) embryo transfer (ET) technology allow the noninvasive transfer of porcine embryos into recipients, overcoming the most important impediment for commercial ET in this species. Although many factors in the porcine ET-field have been recently evaluated, many others remain to be explored. We investigated here the future reproductive performance of donors and recipients after artificial insemination subsequent to the default surgical embryo recovery approach and to the NsDU-ET procedure, respectively. Although surgical embryo collection did not influence subsequent farrowing rates (90.5%), litter size decreased severely (8.9 ± 0.8 piglets) compared to presurgery (10.8 ± 0.3 piglets) and control group (10.7 ± 0.3 piglets). In contrast, NsDU-ETs did neither affect fertility nor prolificacy of recipients in the cycle subsequent to ET, regardless of whether they were pregnant after NsDU-ET or not. These results indicate that while the surgical embryo collection procedure compromises the reproductive future of donor sows, the NsDU-ET approach does not affect the reproductive potential of the recipients after reintroduction to the breeding stock of the farm. Further research is thus needed to improve surgical embryo collection.


Asunto(s)
Transferencia de Embrión/veterinaria , Recolección de Tejidos y Órganos/veterinaria , Animales , Transferencia de Embrión/métodos , Femenino , Tamaño de la Camada , Embarazo , Porcinos , Recolección de Tejidos y Órganos/métodos
13.
Animal ; 11(8): 1330-1335, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28219466

RESUMEN

The improvement in porcine embryo preservation and non-surgical embryo transfer (ET) procedures achieved in recent years represents essential progress for the practical use of ET in the pig industry. This study aimed to evaluate the effects of parity, weaning-to-estrus interval (WEI) and season on reproductive and embryonic parameters at day 6 after insemination of donor sows superovulated after weaning. The selection of donor sows was based on their reproductive history, body condition and parity. The effects of parity at weaning (2 to 3, 4 to 5 or 6 to 7 litters), season (fall, winter and spring), and WEI (estrus within 3 to 4 days), and their interactions on the number of corpus luteum, cysts in sows with cysts, number and quality of viable and transferable embryos, embryo developmental stage and recovery and fertilization rates were evaluated using linear mixed effects models. The analyses showed a lack of significant effects of parity, season, WEI or their interactions on any of the reproductive and embryonic parameters examined. In conclusion, these results demonstrate that fertilization rates and numbers of viable and transferable embryos collected at day 6 of the cycle from superovulated donor sows are not affected by their parity, regardless of the time of the year (from fall to spring) and WEI (3 or 4 days).


Asunto(s)
Transferencia de Embrión/veterinaria , Porcinos/fisiología , Animales , Estro , Femenino , Paridad , Embarazo , Factores de Tiempo , Destete
14.
J Thromb Haemost ; 15(11): 2188-2197, 2017 11.
Artículo en Inglés | MEDLINE | ID: mdl-28834196

RESUMEN

Essentials The Royal disease (RD) is a form of hemophilia B predicted to be caused by a splicing mutation. We generated an iPSC-based model of the disease allowing mechanistic studies at the RNA level. F9 mRNA analysis in iPSC-derived hepatocyte-like cells showed the predicted abnormal splicing. Mutated F9 mRNA level was very low but we also found traces of wild type transcripts. SUMMARY: Background The royal disease is a form of hemophilia B (HB) that affected many descendants of Queen Victoria in the 19th and 20th centuries. It was found to be caused by the mutation F9 c.278-3A>G. Objective To generate a physiological cell model of the disease and to study F9 expression at the RNA level. Methods Using fibroblasts from skin biopsies of a previously identified hemophilic patient bearing the F9 c.278-3A>G mutation and his mother, we generated induced pluripotent stem cells (iPSCs). Both the patient's and mother's iPSCs were differentiated into hepatocyte-like cells (HLCs) and their F9 mRNA was analyzed using next-generation sequencing (NGS). Results and Conclusion We demonstrated the previously predicted aberrant splicing of the F9 transcript as a result of an intronic nucleotide substitution leading to a frameshift and the generation of a premature termination codon (PTC). The F9 mRNA level in the patient's HLCs was significantly reduced compared with that of his mother, suggesting that mutated transcripts undergo nonsense-mediated decay (NMD), a cellular mechanism that degrades PTC-containing mRNAs. We also detected small proportions of correctly spliced transcripts in the patient's HLCs, which, combined with genetic variability in splicing and NMD machineries, could partially explain some clinical variability among affected members of the European royal families who had lifespans above the average. This work allowed the demonstration of the pathologic consequences of an intronic mutation in the F9 gene and represents the first bona fide cellular model of HB allowing the study of rare mutations at the RNA level.


Asunto(s)
Factor IX/genética , Hemofilia B/genética , Hepatocitos/metabolismo , Células Madre Pluripotentes Inducidas/metabolismo , Mutación , ARN Mensajero/genética , Adolescente , Empalme Alternativo , Diferenciación Celular , Línea Celular , Factor IX/metabolismo , Femenino , Predisposición Genética a la Enfermedad , Hemofilia B/sangre , Hemofilia B/diagnóstico , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Masculino , Fenotipo , ARN Mensajero/metabolismo , Análisis de Secuencia de ARN
15.
J Phys Chem B ; 110(47): 24021-9, 2006 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-17125373

RESUMEN

Cobalt oxide (Co3O4) and copper-doped cobalt oxide (CuxCo(3-x)O4) films have been prepared onto titanium support by the thermal decomposition method. The electrodes have been characterized by different techniques such as cyclic voltammetry, scanning electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy (XPS). The effect on the electrochemical and crystallographic properties and surface morphology of the amount of copper in the oxide layer has been analyzed. The XPS spectra correspond to a characteristic monophasic Cu-Co spinel oxides when x is below 1. However, when the copper content exceeds that for the stoichiometric CuCo2O4 spinel, a new CuO phase segregates at the surface. The analysis of the surface cation distribution indicates that Cu(II) has preference for octahedral sites.


Asunto(s)
Cobalto/química , Cobre/química , Nanotecnología/métodos , Óxidos/química , Cationes Bivalentes , Electroquímica , Electrodos , Microanálisis por Sonda Electrónica , Microscopía Electrónica de Rastreo , Espectrometría por Rayos X , Difracción de Rayos X
16.
Eur J Surg Oncol ; 31(2): 205-7, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15698739

RESUMEN

We herein describe a 19-year-old woman who presented with pericardial effusion that resulted in heart tamponade. The clinicopathological study revealed papillary carcinoma of the thyroid metastasized to the heart. Although malignant pericardial effusion is a known complication of thyroid cancer, it is rarely the first manifestation and shows a relatively favourable prognosis despite widespread metastases if adequate treatment is given.


Asunto(s)
Carcinoma Papilar/diagnóstico , Taponamiento Cardíaco/diagnóstico , Neoplasias de la Tiroides/diagnóstico , Adulto , Carcinoma Papilar/patología , Taponamiento Cardíaco/etiología , Diagnóstico Diferencial , Ecocardiografía , Femenino , Neoplasias Cardíacas/diagnóstico , Neoplasias Cardíacas/secundario , Humanos , Derrame Pericárdico/complicaciones , Derrame Pericárdico/diagnóstico , Radiografía Torácica , Neoplasias de la Tiroides/patología
17.
Microb Drug Resist ; 6(2): 111-7, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10990265

RESUMEN

Spontaneous mutants resistant to fluoroquinolones were obtained by exposing Serratia marcescens NIMA (wild-type strain) to increasing concentrations of ciprofloxacin both in liquid and on solid media. Frequencies of mutation ranged from 10(-7) to 10(-9). Active expulsion of antibiotic was explored as a possible mechanism of resistance in mutants as well as changes in topoisomerase target genes. The role of extrusion mechanisms in determining the emergence of multidrug-resistant bacteria was also examined. Mutants resistant to high concentrations of fluoroquinolones had a single mutation in their gyrA QRDR sequences, whereas the moderate resistance in the rest of mutants was due to extrusion of the drug.


Asunto(s)
Antiinfecciosos/farmacología , Permeabilidad de la Membrana Celular , Ciprofloxacina/farmacología , Serratia marcescens/efectos de los fármacos , Antibacterianos/farmacología , Antiinfecciosos/metabolismo , Proteínas de la Membrana Bacteriana Externa/metabolismo , Secuencia de Bases , Ciprofloxacina/metabolismo , Medios de Cultivo , Girasa de ADN , ADN-Topoisomerasas de Tipo II/genética , Farmacorresistencia Microbiana/genética , Resistencia a Múltiples Medicamentos/genética , Humanos , Lipopolisacáridos/metabolismo , Pruebas de Sensibilidad Microbiana , Datos de Secuencia Molecular , Mutación , Serratia marcescens/genética , Serratia marcescens/crecimiento & desarrollo , Serratia marcescens/metabolismo
18.
Photochem Photobiol ; 73(1): 14-9, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11202360

RESUMEN

A fluorescence titration method was applied for the determination of pKa of ciprofloxacin (CPX) in solution. Values of 6.18 +/- 0.05 and 8.76 +/- 0.03 were obtained for pKa1 and pKa2, respectively. The method was used to determine the ionization constants in the presence of liposomes of dipalmitoylphosphatidylcholine (DPPC) and DPPC with 10 mol% of dipalmitoylphosphatidylglycerol. A dependence on the surface charge of liposomes was found which supported the existence of a basic electrostatic interaction between CPX and the phospholipid bilayer. Both pK values for the N-4 butyl-piperazinyl derivative (BCPX) of the parent compound were also determined in solution and in the presence of liposomes. The competition of both drugs for the same binding site as 1-anilino-8-naphtalene sulfonate demonstrate that the interaction is governed by electrostatic forces.


Asunto(s)
Ciprofloxacina/química , Antiinfecciosos/química , Ciprofloxacina/análogos & derivados , Concentración de Iones de Hidrógeno , Liposomas , Fotoquímica , Soluciones , Espectrometría de Fluorescencia , Electricidad Estática
19.
Int J Pharm ; 220(1-2): 53-62, 2001 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-11376967

RESUMEN

Partitioning of a fluoroquinolone antibiotic, ciprofloxacin, and its N-piperazinyl alkyl derivatives, between octanol or Escherichia coli lipid membrane extract and aqueous buffer pH 7.4, was studied. The experimental partition coefficients (Pexp) were corrected at this pH using an expression that includes the microconstant values of each compound. The relationship between the corrected partition coefficients expressed as logP (thermodynamic partition coefficient) and the diffusion through the lipid bilayers ('hydrophobic pathway') of entry has been considered here. In this work, we have explored the possibility of using our model to provide physicochemical evidences to support such a via. The correlation between logP values and antibacterial activities (expressed as minimal inhibitory concentration (MIC) values) of the homologous series of antibiotics against different bacteria were studied. A parabolic behaviour was observed which evidenced that the only increase in lipophilicity does not result in an enhanced antimicrobial activity for the homologous family studied.


Asunto(s)
Antiinfecciosos/farmacología , Ciprofloxacina/farmacología , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Piperazinas/farmacología , Alquilación , Ciprofloxacina/análogos & derivados , Modelos Lineales , Pruebas de Sensibilidad Microbiana , Relación Estructura-Actividad
20.
Transplant Proc ; 36(3): 775-7, 2004 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15110659

RESUMEN

INTRODUCTION: Because of an increased organ shortage, one of the most controversial questions is whether hepatic retransplantation should be offered to transplant recipients with hepatitis C virus (HCV)-related graft failure because of their worse survival and the inevitable denial of other patients to access to primary transplantation. The objective of the present study was to review our experience with HCV-infected transplant recipients undergoing re-orthotopic liver transplantation (OLT) for HCV graft cirrhosis and receiving pegylated interferon and ribavirin on a prophylactic basis. RESULTS: With a median follow-up of 26 months, all 5 patients are alive with stable graft function. Four patients are still receiving pegylated interferon at a mean duration of 20 months (range, 15-32 months). Although none of the patients has cleared HCV RNA by polymerase chain reaction the mean serum levels have decreased significantly when compared with pre-retransplantation amounts. One year after re-OLT, both grade and fibrosis stage had significantly decreased; the rate of post-retransplantation fibrosis progression was significantly lower than that pre-retransplantation (3.4 +/- 0.2 vs 0.6 +/- 0.3; P <.05).


Asunto(s)
Hepatitis C/tratamiento farmacológico , Interferón-alfa/uso terapéutico , Trasplante de Hígado , Adulto , Femenino , Hepacivirus/genética , Hepacivirus/aislamiento & purificación , Hepatitis C/cirugía , Humanos , Interferón alfa-2 , Cirrosis Hepática/etiología , Cirrosis Hepática/cirugía , Pruebas de Función Hepática , Masculino , Persona de Mediana Edad , Selección de Paciente , Polietilenglicoles , ARN Viral/análisis , Proteínas Recombinantes , Reoperación , Resultado del Tratamiento
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA