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1.
J Dent Res ; 102(6): 616-625, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36951356

RESUMEN

Dentinogenesis imperfecta (DI) is the main orodental manifestation of osteogenesis imperfecta (OI) caused by COL1A1 or COL1A2 heterozygous pathogenic variants. Its prevalence varies according to the studied population. Here, we report the molecular analysis of 81 patients with OI followed at reference centers in Brazil and France presenting COL1A1 or COL1A2 variants. Patients were submitted to clinical and radiographic dental examinations to diagnose the presence of DI. In addition, a systematic literature search and a descriptive statistical analysis were performed to investigate OI/DI phenotype-genotype correlation in a worldwide sample. In our cohort, 50 patients had COL1A1 pathogenic variants, and 31 patients had COL1A2 variants. A total of 25 novel variants were identified. Overall, data from a total of 906 individuals with OI were assessed. Results show that DI was more frequent in severe and moderate OI cases. DI prevalence was also more often associated with COL1A2 (67.6%) than with COL1A1 variants (45.4%) because COL1A2 variants mainly lead to qualitative defects that predispose to DI more than quantitative defects. For the first time, 4 DI hotspots were identified. In addition, we showed that 1) glycine substitution by branched and charged amino acids in the α2(I) chain and 2) substitutions occurring in major ligand binding regions-MLRB2 in α1(I) and MLBR 3 in α2(I)-could significantly predict DI (P < 0.05). The accumulated variant data analysis in this study provides a further basis for increasing our comprehension to better predict the occurrence and severity of DI and appropriate OI patient management.


Asunto(s)
Cadena alfa 1 del Colágeno Tipo I , Colágeno Tipo I , Dentinogénesis Imperfecta , Osteogénesis Imperfecta , Humanos , Colágeno Tipo I/genética , Dentinogénesis Imperfecta/genética , Estudios de Asociación Genética , Mutación , Osteogénesis Imperfecta/diagnóstico por imagen , Osteogénesis Imperfecta/genética
2.
In. Ministerio de Salud de Argentina-MSALARG y Desarrollo Social. Secretaria de Salud. Becas de investigación Ramón Carrillo - Arturo Oñativia: anuario 2015. Ciudad Autónoma de Buenos Aires, Ministerio de Salud y Desarrollo Social. Secretaria de Salud, Diciembre 2018. p.35-35.
Monografía en Español | ARGMSAL, BINACIS | ID: biblio-987754

RESUMEN

INTRODUCCIÓN La conducta suicida es un problema de salud pública que impacta de manera directa en el conjunto de la comunidad. Dado que no se posee una notificación al respecto, no se percibe la real magnitud. Los factores asociados a la conducta suicida son importantes en el desencadenamiento de esta problemática. OBJETIVOS Caracterizar la conducta suicida en áreas sanitarias de Tucumán en 2014-2015. MÉTODOS Se realizó un estudio descriptivo transversal para estimar los factores desencadenantes de la conducta suicida en áreas sanitarias seleccionadas de Tucumán durante 2014-2015. La investigación se basó en la identificación de casos de conducta suicida a través de múltiples fuentes de información y apareamiento de los datos registrados en las planillas de conducta suicida. RESULTADOS Durante 2014-2015 se registró un total de 580 casos en las planillas de conducta suicida en el primer nivel de atención. El promedio mensual fue de 24 casos de conducta suicida. El 70% eran mujeres. El promedio de edad fue de 24 años, con un rango de 5 a 73 años. En cuanto al estado civil, hubo un 69% de pacientes solteros, un 23% de casados o en convivencia y un 7% de divorciados. Esto guarda relación directa con el grupo etario, ya que predominan los jóvenes de 10 a 19 años (49%). En lo que respecta al método empleado en el intento de suicidio, la mayoría de los casos registrados (75,5%) se reparten entre las categorías de intoxicación medicamentosa y ahorcamiento. Los casos de intoxicaciones medicamentosas registraron un 45%, con mayoría de mujeres, y el ahorcamiento representó un 31% (población masculina). En tercer lugar, aparecieron los cortes en muñecas (16%). El análisis de los factores desencadenantes mostró prevalencia de la categoría correspondiente a problemas familiares, con un 54% para esta variable. Discusión Es muy importante para la Salud Mental obtener datos claros y precisos sobre la provincia de Tucumán, ya que ellos permiten tener una práctica más sustentable y cercana a las características territoriales.


Asunto(s)
Suicidio , Factores de Riesgo
3.
Rev. argent. endocrinol. metab ; 55(3): 21-30, set. 2018. graf
Artículo en Español | LILACS | ID: biblio-1041741

RESUMEN

RESUMEN La Endotelina-1 (ET1) y Proteína C Reactiva ultrasensible (PCRus) como marcadores de disfunción endotelial (DE) e inflamación vascular en hipotiroidismo subclínico (HS) han mostrado resultados controvertidos. El rol del estrés oxidativo y defensa antioxidante (TRAP) es motivo de discusión. Objetivos Establecer si el HS y la autoinmunidad tiroidea (AIT), excluyendo otros factores de riesgo cardiovascular, pueden causar DE e inflamación vascular, evaluadas a través de ET1 y PCRus, respectivamente. Establecer si TRAP juega algún rol. Evaluar cambios en ET1 y PCRus luego del tratamiento con levotiroxina (LT4). Material y métodos Se evaluaron prospectivamente 70 pacientes divididos en 3 grupos: HS: 41 pacientes (T4 normal,TSH >4,2 y <10 mUI/L), AIT: 10 pacientes eutiroideos (TSH <4,2 mUI/L) con aTPO y/o aTg (+) y Control: 19 pacientes eutiroideos sin AIT. Se excluyeron otros factores de riesgo cardiovascular. Se midió basalmente ET1, PCRus y TRAP plasmáticos, y en HS bajo LT4 (n = 24): ET1 y PCRus. Resultados No hubo diferencias significativas en edad, IMC, perfil lipídico y TRAP. ET1 y PCRus fueron significativamente mayores en pacientes con HS (media ± DS 1,77 ± 0,85 pg/ml y 1,5 ± 0,6 mg/l vs. controles (0,8 ± 0,3 pg/ml y 0,5 ± 0,2 mg/l) p <0,0001 y <0,008 respectivamente. Del mismo modo en AIT (1,4 ± 0.4 pg/ml y 2,3 ± 1,3 mg/l) vs controles p <0,0001 y <0,034, respectivamente. La TSH fue mayor en el grupo AIT vs. Control 2,57 ± 0,88 vs. 1,64 ± 0,5 mUI/L; p = 0,002. En HS bajo LT4 (8,7 ± 3,8 meses) se observó descenso de ET1 (p <0,001). ET1 correlacionó con TSH (r = 0,5 p <0,0001). El punto de corte de ET1 mediante curva ROC fue 1,32 pg/ml (Sensibilidad 81,6%-Especificidad 75%). Conclusiones ET1 y PCRus resultaron marcadores útiles para evaluar DE e inflamación vascular asociadas a HS. La defensa antioxidante no ejercería un rol en estos mecanismos. El tratamiento con LT4 produjo una significativa caída de ET1, pudiendo necesitarse un período más largo de eutiroidismo para normalizarla. En AIT, niveles de TSH >2,5 mUI/L podrían sugerir un mínimo grado de hipotiroidismo justificando la elevación en ET1 y PCR, sin descartar el rol de la AIT "per se".


ABSTRACT The measurement of endothelin-1 (ET1) and high sensitivity C-reactive protein (hsCRP) as markers of endothelial dysfunction (ED) and vascular inflammation in subclinical hypothyroidism (SH) has shown controversial results. The role of oxidative stress and antioxidant defense (TRAP) is a matter of discussion. Objectives To establish if SH and thyroid autoimmunity (TAI), excluding other cardiovascular risk factors, may cause ED and vascular inflammation, evaluated through the measurement of ET1 and hsCRP respectively. To determine if TRAP could have some role. Additionally, changes in these parameters after treatment with levothyroxine (LT4) will be evaluated. Material and methods: 70 patients were prospectively evaluated. They were classified into: SH Group: 41 patients (normal T4, TSH> 4.2 and <10 mIU/L), TAI Group: 10 euthyroid patients (TSH <4.2 mUI/L) with positive aTPO and/or aTg and Control Group: 19 euthyroid patients without TAI. Other cardiovascular risk factors were excluded in patients and controls. Plasma ET1, hsCRP and TRAP were measured basally, and ET1 and hsCRP under LT4 therapy in the HS Group. Results There were no significant differences between the 3 groups in age, BMI, lipids and TRAP. ET1 and hsCRP were significantly higher in patients with SH (mean ± SD 1.77 ± 0.85 pg/ml and 1.5 ± 0.6 mg/l) vs. controls (0.8 ± 0.3 pg/ml y 0.5 ± 0.2 mg/l) p <0.0001 y <0.008 respectively. Similarly, in TAI patients (1.4 ± 0.4 pg/ml y 2.3 ± 1.3 mg/l) vs controls, p <0.0001 and <0.034, respectively. TSH was higher in the TAI patients versus control group (2.5 ± 0.88 versus 1.64 ± 0.5 mIU/L, p = 0.002). Twenty-four patients with SH showed a significant decrease in ET1 (p <0.001) under treatment with LT4 (8.7 ± 3.8 months). ET1 had a highly significant correlation (p <0.0001) with TSH (r = 0.5). The cut-off level of ET1 established by ROC curve was 1.32 pg/ml (Sensitivity 81.6%-Specificity 75%). Conclusions ET1 and hsCRP were useful markers to evaluate ED and vascular inflammation associated with SH. There were no differences in TRAP levels between patients and controls, so it does not appear that oxidative stress would have played any role. Treatment with LT4 produced a significant drop in ET1. Probably, a longer period of euthyroidism might be necessary to normalize ET1 levels. In TAI Group, TSH levels >2.5 mUI/L could suggest a "minimal degree" of hypothyroidism justifying the elevation in ET1 and hs CRP. The role of the TAI "per se" couldn't be completely ruled out.


Asunto(s)
Humanos , Masculino , Femenino , Persona de Mediana Edad , Anciano , Proteína C-Reactiva/efectos de los fármacos , Endotelina-1/efectos de los fármacos , Hipotiroidismo/complicaciones , Tiroxina/uso terapéutico , Proteína C-Reactiva/análisis , Autoinmunidad/efectos de los fármacos , Estudios de Casos y Controles , Endotelina-1/análisis , Antioxidantes/metabolismo
4.
Neurología (Barc., Ed. impr.) ; 32(4): 224-229, mayo 2017. ilus, graf
Artículo en Español | IBECS | ID: ibc-162026

RESUMEN

Introducción. El ictus es una patología neurológica tiempo dependiente. El Área V de salud de la Región de Murcia posee unas determinadas características demográficas y geográficas que hacen imprescindible la creación de propuestas de mejora concretas para garantizar un correcto funcionamiento del código ictus. Los objetivos de este estudio fueron valorar la opinión de los profesionales del Área respecto a la activación y la práctica del mismo y compartir esas propuestas de mejora con el grupo multidisciplinar de mejora del código ictus regional. Sujetos y método. Se realizó un estudio descriptivo transversal, utilizando la técnica Delphi para elaborar un cuestionario dirigido al personal médico y de enfermería de todos los niveles asistenciales. El cuestionario era anónimo y de cumplimentación telemática; se envió a 154 profesionales. El análisis se realizó con el método DAFO (debilidades, amenazas, fortalezas y oportunidades de mejora). Resultados. Se recogieron 51 cuestionarios. Las propuestas de mejora principales fueron: la formación, la comunicación con el neurólogo, la distancia, las pruebas de imagen, la motivación a los profesionales y la concienciación a la población general. Conclusiones. En la bibliografía actual, se recogen la mayoría de las intervenciones que propusieron los participantes. Las propuestas de mejora se transmitieron al grupo de Mejora del Código Ictus de la Región de Murcia (AU)


Introduction. Stroke is a time-dependent neurological disease. Health District V in the Murcia Health System has certain demographic and geographical characteristics that make it necessary to create specific improvement strategies to ensure proper functioning of code stroke (CS). The study objectives were to assess local professionals’ opinions about code stroke activation and procedure, and to share these suggestions with the regional multidisciplinary group for code stroke. Subjects and method. This cross-sectional and descriptive study used the Delphi technique to develop a questionnaire for doctors and nurses working at all care levels in Area V. An anonymous electronic survey was sent to 154 professionals. The analysis was performed using the SWOT method (Strengths, Weaknesses, Opportunities, and Threats). Results. Researchers collected 51 questionnaires. The main proposals were providing training, promoting communication with the neurologist, overcoming physical distances, using diagnostic imaging tests, motivating professionals, and raising awareness in the general population. Conclusions. Most of the interventions proposed by the participants have been listed in published literature. These improvement proposals were forwarded to the Regional Code Stroke Improvement Group (AU)


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Encuestas de Atención de la Salud , Accidente Cerebrovascular/epidemiología , Servicios Prehospitalarios , Atención Primaria de Salud/tendencias , España/epidemiología , Estudios Transversales/estadística & datos numéricos , Encuestas y Cuestionarios , Refuerzo Biomédico/estadística & datos numéricos
5.
Neurologia ; 32(4): 224-229, 2017 May.
Artículo en Inglés, Español | MEDLINE | ID: mdl-26778733

RESUMEN

INTRODUCTION: Stroke is a time-dependent neurological disease. Health District V in the Murcia Health System has certain demographic and geographical characteristics that make it necessary to create specific improvement strategies to ensure proper functioning of code stroke (CS). The study objectives were to assess local professionals' opinions about code stroke activation and procedure, and to share these suggestions with the regional multidisciplinary group for code stroke. SUBJECTS AND METHOD: This cross-sectional and descriptive study used the Delphi technique to develop a questionnaire for doctors and nurses working at all care levels in Area V. An anonymous electronic survey was sent to 154 professionals. The analysis was performed using the SWOT method (Strengths, Weaknesses, Opportunities, and Threats). RESULTS: Researchers collected 51 questionnaires. The main proposals were providing training, promoting communication with the neurologist, overcoming physical distances, using diagnostic imaging tests, motivating professionals, and raising awareness in the general population. CONCLUSIONS: Most of the interventions proposed by the participants have been listed in published literature. These improvement proposals were forwarded to the Regional Code Stroke Improvement Group.


Asunto(s)
Adhesión a Directriz/normas , Personal de Salud/educación , Accidente Cerebrovascular/diagnóstico , Estudios Transversales , Técnica Delphi , Humanos , Enfermeras y Enfermeros , Médicos , Encuestas y Cuestionarios , Factores de Tiempo
6.
Clin Chim Acta ; 447: 43-6, 2015 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-25979693

RESUMEN

BACKGROUND: We report a case of interference in thyroglobulin (Tg) measurement in a woman with differentiated thyroid cancer and rheumatoid arthritis history. Due to discordant Tg in relation to TSH concentrations and negative images, we investigated possible interference in the measurement of Tg. METHODS: During the follow-up we measured Tg by chemiluminescence (TgQL) using Immulite 2000 immunoassay system. To investigate possible interference in Tg measurement, we made serial dilutions, re-testing of Tg by an alternative method: electrochemiluminescence, Cobas 6000 analyzer (TgEQL), recovery test of Tg and polyethylene glycol (PEG) 6000 precipitation. RESULTS: During the patient follow-up, the TgQL ranged between <0.3 and 16.1ng/ml. In the evaluated serum samples very high titers of rheumatoid factor (RF) were found. When RF titers were lowered post PEG precipitation, Tg QL concentrations became undetectable. CONCLUSION: We describe an unusual case of interference in Tg assay due to RF. When disagreement among Tg concentrations, images and clinical features is observed, we suggest taking into account the evaluation of possible Tg interference to avoid unnecessary complementary exams and inappropriate treatment.


Asunto(s)
Análisis Químico de la Sangre/métodos , Factor Reumatoide/inmunología , Tiroglobulina/sangre , Adulto , Reacciones Falso Positivas , Femenino , Humanos , Inmunoensayo , Mediciones Luminiscentes , Neoplasias de la Tiroides/sangre , Neoplasias de la Tiroides/inmunología
7.
Rev. argent. endocrinol. metab ; 50(2): 63-70, jul. 2013. ilus, tab
Artículo en Español | LILACS | ID: lil-694891

RESUMEN

Ante la baja frecuencia del carcinoma medular de tiroides (CMT), en el Departamento de Tiroides de SAEM nos propusimos realizar un estudio de cohorte, observacional, retrospectivo y multicéntrico. Se incluyeron 219 pacientes con diagnóstico histológico de CMT. El 65 % fueron mujeres, la edad promedio fue de 39 ± 20 años (1 a 84 años); 44-% de los casos fueron familiares. Las formas de presentación más frecuentes fueron nódulo tiroideo (58 %) y pesquisa genética por antecedente familiar (22 %). Si bien la citología tiroidea fue diagnóstica de CMT en el 39 % de los casos, fue determinante de indicación quirúrgica en el 79 %. En el 47 % de los pacientes el diagnóstico de CMT se obtuvo previamente al tratamiento quirúrgico inicial por punción aspiración con aguja fina (PAAF), estudio genético o nivel de calcitonina (CT)). El 65 % se presentó en estadios avanzados (TNM III y IV). El estudio del protoncogen RET se realizó en 162 pacientes (74 %). En el 49 % se observó mutación siendo la más frecuente (76 %) en el codón 634. La forma hereditaria más frecuentemente observada fue el síndrome de neoplasia endocrina múltiple (NEM) 2A (57 % de los casos familiares), seguida por carcinoma medular familiar (25 %) y NEM 2B (13 %). Los casos familiares tuvieron menor edad al diagnóstico y mayor frecuencia de diagnóstico prequirúrgico. Los casos índice tuvieron mayor edad al momento del diagnóstico, mayores niveles de antígeno carcinoembrionario (CEA) y CT prequirúrgicos, mayor proporción de estadios III y IV y mayor porcentaje de evidencia de enfermedad al momento de la última consulta que aquellos detectados por pesquisa. En 143 pacientes (65 %) se obtuvieron registros completos de seguimiento en los que se analizaron los factores relacionados con la evolución. La mediana de seguimiento fue de 44 meses: fallecieron 21 pacientes (14,6 %) y 122 (86 %) viven; 76 de estos (54 %) se encuentran libres de enfermedad. El grupo con evidencia de enfermedad se presentó en estadios más avanzados. Resultaron factores de mayor riesgo para evidencia de enfermedad: sexo masculino, CMT esporádico, niveles elevados de CT prequirúrgicos, estadio IV y presencia de metástasis. Los niveles de CT posquirúrgicos fueron menores en aquellos pacientes que en la evolución final no presentaron evidencia de enfermedad. El principal factor pronóstico de la evolución de los pacientes con CMT fue el estadio de presentación, determinando la importancia del diagnóstico precoz con el fin de poder implementar un tratamiento quirúrgico curativo en estadios menos avanzados.


Due to the low frequency of medullary thyroid cancer (MTC), an observational, cohort, retrospective multicenter study was conducted at the Thyroid Department of the Endocrine and Metabolism Argentine Society (SAEM). We included 219 patients with histologically proven MTC, with a mean age of 39 ± 20 yr (range 1-84 years). Sixty five percent were women and 44% were familial cases. The most common presentations were thyroid nodule (58 %) and genetic screening due to family history (22 %). In 39 % of patients, diagnosis of MTC was made by fine needle aspiration, but cytology led to surgery in 79 %. In 47 % of patients, MTC was diagnosed by cytology, calcitonin (CT) levels or genetic studies prior to initial surgery. Sixty five percent of patients had advanced stages of the disease (TNM III or IV) at diagnosis. Proto-oncogene RET was studied in 162 patients (74 %). In 49% a mutation was reported, most frequently in codon 634 (76 %). Regarding hereditary forms of MTC, MEN 2A was the most frequent (57%), followed by familial MTC in 25 % and MEN 2B in 13 % of cases. Familial cases were younger subjects and had more frequently a pre-surgery diagnosis. Index cases were older, with higher CEA and CT levels, presented in more advanced stages and had more frequently evidence of disease at final assessment than patients who were diagnosed by genetic screening. Follow-up records of 143 patients were analyzed (65%); median time was 44 months; 21 patients died (14.6 %) and 122 survived (86 %), 76 showed no evidence of disease (NED) (54 %). High risk factors for evidence of disease at the final evaluation were: male gender, sporadic MTC, higher CT pre-surgery levels, stage IV and metastasis. Post surgery CT levels were lower in patients with NED. Stage at initial diagnosis was the main prognostic factor in patients with MTC, determining the importance of early detection for performing curative surgery in less advanced stages.

8.
Rev. argent. endocrinol. metab ; 50(2): 63-70, jul. 2013. ilus, tab
Artículo en Español | BINACIS | ID: bin-130696

RESUMEN

Ante la baja frecuencia del carcinoma medular de tiroides (CMT), en el Departamento de Tiroides de SAEM nos propusimos realizar un estudio de cohorte, observacional, retrospectivo y multicéntrico. Se incluyeron 219 pacientes con diagnóstico histológico de CMT. El 65 % fueron mujeres, la edad promedio fue de 39 ± 20 años (1 a 84 años); 44-% de los casos fueron familiares. Las formas de presentación más frecuentes fueron nódulo tiroideo (58 %) y pesquisa genética por antecedente familiar (22 %). Si bien la citología tiroidea fue diagnóstica de CMT en el 39 % de los casos, fue determinante de indicación quirúrgica en el 79 %. En el 47 % de los pacientes el diagnóstico de CMT se obtuvo previamente al tratamiento quirúrgico inicial por punción aspiración con aguja fina (PAAF), estudio genético o nivel de calcitonina (CT)). El 65 % se presentó en estadios avanzados (TNM III y IV). El estudio del protoncogen RET se realizó en 162 pacientes (74 %). En el 49 % se observó mutación siendo la más frecuente (76 %) en el codón 634. La forma hereditaria más frecuentemente observada fue el síndrome de neoplasia endocrina múltiple (NEM) 2A (57 % de los casos familiares), seguida por carcinoma medular familiar (25 %) y NEM 2B (13 %). Los casos familiares tuvieron menor edad al diagnóstico y mayor frecuencia de diagnóstico prequirúrgico. Los casos índice tuvieron mayor edad al momento del diagnóstico, mayores niveles de antígeno carcinoembrionario (CEA) y CT prequirúrgicos, mayor proporción de estadios III y IV y mayor porcentaje de evidencia de enfermedad al momento de la última consulta que aquellos detectados por pesquisa. En 143 pacientes (65 %) se obtuvieron registros completos de seguimiento en los que se analizaron los factores relacionados con la evolución. La mediana de seguimiento fue de 44 meses: fallecieron 21 pacientes (14,6 %) y 122 (86 %) viven; 76 de estos (54 %) se encuentran libres de enfermedad. El grupo con evidencia de enfermedad se presentó en estadios más avanzados. Resultaron factores de mayor riesgo para evidencia de enfermedad: sexo masculino, CMT esporádico, niveles elevados de CT prequirúrgicos, estadio IV y presencia de metástasis. Los niveles de CT posquirúrgicos fueron menores en aquellos pacientes que en la evolución final no presentaron evidencia de enfermedad. El principal factor pronóstico de la evolución de los pacientes con CMT fue el estadio de presentación, determinando la importancia del diagnóstico precoz con el fin de poder implementar un tratamiento quirúrgico curativo en estadios menos avanzados.(AU)


Due to the low frequency of medullary thyroid cancer (MTC), an observational, cohort, retrospective multicenter study was conducted at the Thyroid Department of the Endocrine and Metabolism Argentine Society (SAEM). We included 219 patients with histologically proven MTC, with a mean age of 39 ± 20 yr (range 1-84 years). Sixty five percent were women and 44% were familial cases. The most common presentations were thyroid nodule (58 %) and genetic screening due to family history (22 %). In 39 % of patients, diagnosis of MTC was made by fine needle aspiration, but cytology led to surgery in 79 %. In 47 % of patients, MTC was diagnosed by cytology, calcitonin (CT) levels or genetic studies prior to initial surgery. Sixty five percent of patients had advanced stages of the disease (TNM III or IV) at diagnosis. Proto-oncogene RET was studied in 162 patients (74 %). In 49% a mutation was reported, most frequently in codon 634 (76 %). Regarding hereditary forms of MTC, MEN 2A was the most frequent (57%), followed by familial MTC in 25 % and MEN 2B in 13 % of cases. Familial cases were younger subjects and had more frequently a pre-surgery diagnosis. Index cases were older, with higher CEA and CT levels, presented in more advanced stages and had more frequently evidence of disease at final assessment than patients who were diagnosed by genetic screening. Follow-up records of 143 patients were analyzed (65%); median time was 44 months; 21 patients died (14.6 %) and 122 survived (86 %), 76 showed no evidence of disease (NED) (54 %). High risk factors for evidence of disease at the final evaluation were: male gender, sporadic MTC, higher CT pre-surgery levels, stage IV and metastasis. Post surgery CT levels were lower in patients with NED. Stage at initial diagnosis was the main prognostic factor in patients with MTC, determining the importance of early detection for performing curative surgery in less advanced stages.(AU)

9.
Genet Couns ; 23(2): 313-8, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22876592

RESUMEN

We report on an 8-year-old girl with a typical Down syndrome phenotype and a 46,XX,rea(21)(qter-->p12::q21.2-->qter).ish rea(21)(qter-->pl2::q21.2-->qter)(LSI 21++,AML1++) karyotype; the mother had normal chromosomes but the father was unavailable. The great resemblance of the patient's rearranged chromosome to the rec(21)dup(q) from a parental pericentric inversion suggests that it would be better depicted as a recombinant-like chromosome. Altogether, 13 recombinant-like chromosomes of de novo or unknown (parents not karyotyped) origin have been described. Although these rearranged chromosomes should formally be described as derivatives because no parental inversion is identified, we underlie that the unofficial term recombinant-like would be more appropriate because no "multiple aberrations within a single chromosome" (as required by the ISCN) have been proved, not to mention that the term derivative usually designates abnormal chromosomes resulting from a translocation between non homologous chromosomes. Accordingly, we prefer to identify such rearrangements of a single chromosome precisely with the more neutral and sanctioned term rea (expanding its use to designate a rearranged chromosome) coupled with the lengthy description of the abnormal chromosome. We assume that the rea(21) chromosomes result from illegitimate recombination between non allelic homologous LCRs located in both the short and long arms.


Asunto(s)
Duplicación Cromosómica/genética , Cromosomas Humanos Par 21/genética , Síndrome de Down/genética , Terminología como Asunto , Niño , Aberraciones Cromosómicas , Deleción Cromosómica , Inversión Cromosómica , Femenino , Humanos , Hibridación Fluorescente in Situ , Cariotipo , Cariotipificación , Prohibitinas , Mapeo Restrictivo , Translocación Genética
10.
Plant Cell Environ ; 35(8): 1483-99, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22394204

RESUMEN

Nitric oxide (NO) regulates a wide range of plant processes from development to environmental adaptation. In this study, we investigated the production and/or function of NO in Arabidopsis thaliana leaf discs and plants elicited by oligogalacturonides (OGs) and challenged with Botrytis cinerea. We provided evidence that OGs triggered a fast and long lasting NO production which was Ca(2+) dependent and involved nitrate reductase (NR). Accordingly, OGs triggered an increase of both NR activity and transcript accumulation. NO production was also sensitive to the mammalian NO synthase inhibitor L-NAME. Intriguingly, we showed that L-NAME affected NO production by interfering with NR activity, thus questioning the mechanisms of how this compound impairs NO synthesis in plants. We further demonstrated that NO modulates RBOHD-mediated reactive oxygen species (ROS) production and participates in the regulation of OG-responsive genes such as anionic peroxidase (PER4) and a ß-1,3-glucanase. Mutant plants impaired in PER4 and ß-1,3-glucanase, as well as Col-0 plants treated with the NO scavenger cPTIO, were more susceptible to B. cinerea. Taken together, our investigation deciphers part of the mechanisms linking NO production, NO-induced effects and basal resistance to B. cinerea.


Asunto(s)
Arabidopsis/inmunología , Botrytis/patogenicidad , Ácidos Hexurónicos/metabolismo , Óxido Nítrico/biosíntesis , Botrytis/inmunología , Calcio/metabolismo , Transporte Iónico , Especies Reactivas de Oxígeno/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa
11.
Rev. argent. endocrinol. metab ; 48(3): 149-157, set. 2011. graf, tab
Artículo en Español | LILACS | ID: lil-642002

RESUMEN

Introducción: La presencia de nódulos tiroideos palpables en la población general, es uno de los signos clínicos tiroideos más frecuentes en la práctica diaria. Objetivos: 1) establecer la prevalencia de las distintas patologías en bocio nodular único palpable y analizar sus características y su relación con los resultados citológicos. 2) analizar la existencia de diferencias regionales en Argentina. Pacientes y Métodos: Estudio prospectivo de 739 pacientes con bocio nodular único palpable evaluados entre el 1/1/2000 y el 31/12/2001 en Centros de Buenos Aires, Bahía Blanca, Mendoza y La Pampa. Se recabaron datos de examen clínico, ecografía tiroidea, TSH, ATPO y citología por punción con aguja fina. (PAAF). Fue utilizado para el análisis estadístico Correlación de Pearson, X2 y Test de Fisher. Resultados: la edad (X ± DS) fue 46,3 ± 14 años, 93,1 % eran de sexo femenino. El 1,6 % tenía historia de radiación en cuello y el 29,9 % antecedentes familiares de patología tiroidea. Hallazgos clínicos: disfagia en el 7,9 %, disfonía 3,5 %, crecimiento nodular en los últimos 6 meses 19,2 %, consistencia dura el 24,7 %, fijeza a estructuras adyacentes 1,5 % y adenopatías en el 3 %. Hallazgos bioquímicos: TSH normal en el 81,2 % y ATPO positivos en el 30,3 % de los casos. Características Ecográficas: nódulos sólidos: 53,1 %, hipoecoicos: 63,8 %, microcalcificaciones 10,3 %, halo incompleto: 15 %, multinodular: 30,5 %, tiroides heterogénea: 60,2 % y adenopatías: 3,8 %. Hallazgos citológicos: En el 86,8 % de los casos fue necesario solo una punción para llegar al diagnóstico. Insatisfactorio (excluyendo quiste): 3,2 %: benignos: 77,3 %; sospechosos: 12,6 % y cáncer: 7 % (42 papilar, 2 medular y 3 sin especificar). Una correlación significativa (p<0,02) fue observada entre citología maligna y crecimiento rápido, dureza, fijeza a estructuras vecinas, nódulo sólido, halo incompleto y adenopatías aunque estos parámetros son más frecuentes en números absolutos en nódulos benignos. La mayoría de las cirugías fueron indicadas en base al hallazgo citológico. El diagnóstico histológico de los 96 pacientes que fueron operados mostró 51 carcinomas, de los cuales solo dos tenían citología benigna y 31 adenomas. Conclusión: Los nódulos palpables únicos fueron más frecuentes en mujeres eutiroideas en la edad media de la vida. Un tercio tenía historia familiar de patología tiroidea, similar al porcentaje hallado de ATPO positivos. Por ecografía los nódulos fueron predominantemente sólidos, hipoecoicos, únicos con resto de la glándula tiroides heterogénea. La PAAF fue predominantemente benigna. El crecimiento rápido, la dureza, la fijeza a estructuras adyacentes, el halo incompleto y la presencia de adenopatías fueron relacionados con malignidad, pero la benignidad fue más frecuente. En la mayoría de los pacientes la cirugía fue recomendada por los hallazgos citológicos. Nuestros resultados son similares a los reportados en otras áreas geográficas.


Introduction: the presence of palpable thyroid nodules in the general population is one of the most common clinical signs of thyroid disease in daily practice. Objectives: 1) To assess the prevalence of pathologies, clinical and cytological findings of single palpable thyroid nodules (SPTN) in Argentina. 2) Analyze the regional differences in Argentina. Methods: Prospective study of 739 patients with STPN were evaluated at centres in Buenos Aires, Bahía Blanca, Mendoza, and La Pampa between 1/1/00 and 12/31/01. Clinical examination, thyroid ultrasound scan (US), TSH, TPOAb and fine needle aspirations (FNA) were performed. Statistics: Pearson Correlation, X2 & Fisher Tests. Results: Age (X ± SD) 46 ± 14ys: 93.1 % were women. Previous history of neck radiation & familial thyroid disease were found in 1.6 and 29.9 % respectively. Clinical findings: dysphagia: 7.9 %; dysphonia: 3.5%; nodule growth: 19.2 %; hard consistence: 24.7 %; fixation to adjacent structure: 1.5 % and lymphadenopathies (ADP): 3 %. Biochemical findings: TSH was normal in 81.2 % & TPOAb+ in 30.3 %. US features: solid: 53.1 %; hypoechoic: 63.8 %; microcalcifications: 10.3 %; incomplete halo: 15 %; more than 1 nodule: 30.5 %; thyroid heterogeneity: 60.2 % and ADP: 3.8 %. Cytology: Only 1 FNA was needed in 86.8%. Unsatisfactory (excluding cysts): 3.2 %; benign: 77.2%; suspicious: 12.6 % and cancer: 7 % (42 papillary, 2 medullary and 3 non specified). A significant correlation (p<0.02) was established between malignant nodules and rapid growth, hard, fixed, solid nodule, incomplete halo and ADP, though these parameters were more frequent (in absolute number) in benign nodules. Surgery was mainly indicated based on FNA results. Histological diagnosis of 96 patients who underwent surgery showed 51 carcinomas, of which only 2 were cytologically benign and 31 adenomas. Conclusion: Palpable single nodules were more frequent in middle aged euthyroid women. One third had familial thyroid pathology, similar to the presence of TPOAb. On US, nodules were predominantly solid, hypoechoic, single with heterogeneous thyroid gland. FNA was predominantly benign. Rapid growth, hard, fixed, solid nodule, incomplete halo and ADP were associated with malignancy, but benignity was more common. In most of the patients surgery was recommended based on cytological findings. Our results are similar to those reported in other geographic areas.

12.
Rev. argent. endocrinol. metab ; 47(3): 18-24, jul.-set. 2010. ilus, tab
Artículo en Español | LILACS | ID: lil-641974

RESUMEN

El carcinoma diferenciado de tiroides en quiste tirogloso (CaQT) es una rara entidad. En diferentes series de pacientes operados por quistes tiroglosos su incidencia fue del 0.7 al 1.07%. Luego de la extirpación del quiste por el procedimiento de Sistrunk, no hay consenso sobre la indicación de tiroidectomía total, radioablación y/o terapéutica supresiva con levotiroxina. El objetivo del Departamento de tiroides de SAEM, fue evaluar: formas de presentación, evolución clínica, métodos diagnósticos de utilidad y tratamiento para consensuar futuras conductas. Material y Métodos: Estudio multicéntrico, retrospectivo en 22 pacientes entre 10 a 69 años, 15 mujeres y 7 varones. Resultados: El tamaño de los quistes osciló entre 1 y 8 cm (Mediana= 3.0 cm, Χ ± DS= 3.7 ± 2.2 cm). La mitad de los pacientes presentó crecimiento del quiste en los 6 meses previos a la cirugía. La punción resultó sospechosa en 2/5 quistes y positiva en uno. La ecografía tiroidea evidenció nódulos en 4/13 casos (30%). Se realizó tiroidectomía en 17/22 pacientes (total: 15 y subtotal: 2). La histología del CaQT demostró carcinoma papilar en 21 y carcinoma folicular en uno. Hubo coexistencia de cáncer intratiroideo en el 23.5% de los casos, ninguno multicéntrico. Dos pacientes presentaron metástasis ganglionares y otro tuvo compromiso muscular (ninguno de ellos coexistió con cáncer intratiroideo). Se radioablacionó a 13 pacientes. En 9/11 pacientes la tiroglobulina permaneció indetectable durante el seguimiento (1 a 14 años). Conclusiones: 1) Realizar ecografía de cuello y punción ecoguiada a todo paciente con quiste tirogloso. 2) En caso de CaQT combinar simultáneamente tiroidectomía total y procedimiento de Sistrunk. 3) Evaluar radioablación complementaria y tratamiento supresivo con levotiroxina en cada caso. 4) Efectuar el seguimiento tal como en los carcinomas ortotópicos.


Differentiated thyroid carcinoma (DTC) in thyroglosal duct cyst (TGDC) is rare, ranging from 0.7 to 1.07% in different series. After the surgery of choice (Sistrunk procedure) the other alternative treatments such as thyroidectomy (Tx), radioiodine and L-T4 therapy are controversial. OBJECTIVE: to evaluate several and controversial aspects in the largest series of DTC in TGDC reported in the literature. Subjects and methods: retrospective multicentric study: n= 22, aged 10-69 yrs. (15 females and 7 men) who underwent the Sistrunk procedure for TGDC. Results: none of the TGDC was less than 1 cm (median 3.0 cm, Χ±SD= 3.7 ± 2.2cm). In half of them there was an increased cystic size in the last 6 months before surgery. Cyst FNA was suspicious in 2/5 and positive in one, whereas the histological diagnosis of the operated TGCD was papillary cancer in 21 and 1 follicular carcinoma. Thyroid ultrasound (US) (n=13) showed nodules in 30% of the cases. Tx was performed in 17/22 (total: 15, subtotal: 2). Thyroid DTC coexisted in 4/17 (23.5%), and was unilateral in all of them. Lymph node metastases were present in 2 adults and muscle involvement was found in the 10-year old girl. None of these 3 patients had overt thyroid lesions. 131-I therapy was performed in 10 patients. In 9 out of 11 subjects Tg remained undetectable during follow-up (1-14yrs.). Persistent high Tg was present in one case without thyroid DTC. Conclusions: 1) Ultrasonography and FNAB should be performed to every patient with thyroglossal duct cyst 2) In case of TGDC, total Tx and Sistrunk's procedure should be simultaneously combined 3) 131-I therapy and L-T4 suppressive treatment should be evaluated in every case 4) Follow-up as in the DTC.


Asunto(s)
Humanos , Masculino , Femenino , Niño , Adolescente , Adulto , Persona de Mediana Edad , Anciano , Quiste Tirogloso/cirugía , Quiste Tirogloso/diagnóstico , Neoplasias de la Tiroides/diagnóstico , Neoplasias de la Tiroides/terapia , Terapia Recuperativa/métodos
13.
J Comp Neurol ; 504(4): 363-78, 2007 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-17663442

RESUMEN

The types of sodium channels that are expressed by neurons shape the rising phase of action potentials and influence patterns of action potential discharge. With regard to the enteric nervous system (ENS), there is uncertainty about which channels are expressed, and in particular it is unknown whether Na(v)1.7 is present. We designed specific probes for the guinea pig Na(v)1.7 alpha subunit as well as for the other tetrodotoxin (TTX)-sensitive alpha subunits (Na(v)1.1, Na(v)1.2, Na(v)1.3, and Na(v)1.6) in order to perform in situ hybridization (ISH) histochemistry on guinea pig myenteric ganglia. We established that only Na(v)1.7 mRNA and Na(v)1.3 mRNA are expressed in these ganglia. The ISH signal for Na(v)1.7 transcripts was found in seemingly all the myenteric neurons. The expression of the Na(v)1.3 alpha subunit was confirmed by immunohistochemistry in a large proportion (62%) of the myenteric neuron population. This population included enteric sensory neurons. Na(v)1.6 immunoreactivity, absent from myenteric neurons, was detected in glial cells only when a high anti-Na(v)1.6 antibody concentration was used. This suggests that the Na(v)1.6 alpha subunit and mRNA are present only at low levels, which is consistent with the fact that no Na(v)1.6 mRNA could be detected in the ENS by ISH. The fact that adult myenteric neurons are endowed with only two TTX-sensitive alpha subunits, namely, Na(v)1.3 and Na(v)1.7, emphasizes the singularity of the ENS. Both these subunits, known to have slow-inactivation kinetics, are well adapted for generating action potentials from slow excitatory postsynaptic potentials, a mode of synaptic transmission that applies to all ENS neuron types.


Asunto(s)
Sistema Nervioso Entérico/metabolismo , Canales de Sodio/metabolismo , Animales , Encéfalo/citología , Encéfalo/metabolismo , Sistema Nervioso Entérico/citología , Ganglios Espinales/citología , Ganglios Espinales/metabolismo , Cobayas , Inmunohistoquímica , Hibridación in Situ/métodos , Neuronas Aferentes/metabolismo , Sondas de Oligonucleótidos , Subunidades de Proteína/clasificación , Subunidades de Proteína/genética , ARN Mensajero/análisis , Nervio Ciático/citología , Nervio Ciático/metabolismo , Sensibilidad y Especificidad , Canales de Sodio/efectos de los fármacos , Canales de Sodio/genética , Tetrodotoxina , Distribución Tisular
14.
Thyroid ; 12(1): 63-8, 2002 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11838732

RESUMEN

We studied the evolution of 150 pregnancies corresponding to 114 women (16-39 years old) with primary hypothyroidism. Fifty-one pregnancies (34%) were conceived under hypothyroidism: 16 overt (X +/- standard deviation [SD], thyroxine [T4]: 2.44 +/- 0.7 microg/dL; thyrotropin [TSH]: 33.4 +/- 8.82 mIU/L), and 35 subclinical hypothyroidism (T4: 6.93 +/- 1.88 microg/dL; TSH: 12.87 +/- 8.43 mIU/L); 99 pregnancies were conceived under euthyroidism while undergoing thyroid therapy. When treatment with levothyroxine was inadequate, the outcome of pregnancy was abortion in 60% of overtly hypothyroid patients and in 71.4% of subclinically hypothyroid patients, premature delivery in 20% and 7.2% respectively, and term delivery in 20% and 21.4%, respectively. When treatment was adequate, 100% of overtly hypothyroid patients and 90.5% of subclinically hypothyroid patients carried pregnancies to term; there were no abortions in any of the groups. Abortions, premature and term deliveries in patients who were euthyroid on levothyroxine at the time of conception were 4%, 11.1% and 84.9% respectively. Of the patients receiving levothyroxine therapy before conception, 69.5% had to increase the dose (mean increase 46.2 +/- 29.6 microg/d). Of 126 evaluated newborns, 110 were delivered at term while 16 were premature. Eight newborns, 4 were premature, had congenital malformations (6.3%), and 4 died. Our results show that the evolution of pregnancies did not depend on whether the hypothyroidism was overt or subclinical but mainly on the treatment received. The adequate treatment of hypothyroidism during gestation minimizes risks and generally, makes it possible for pregnancies to be carried to term without complications.


Asunto(s)
Hipotiroidismo/complicaciones , Complicaciones del Embarazo , Aborto Espontáneo/epidemiología , Adolescente , Adulto , Anomalías Congénitas/epidemiología , Hipotiroidismo Congénito , Femenino , Edad Gestacional , Humanos , Hipertiroidismo/epidemiología , Hipotiroidismo/tratamiento farmacológico , Recién Nacido , Recien Nacido Prematuro , Embarazo , Resultado del Embarazo , Tirotropina/sangre , Tiroxina/administración & dosificación , Tiroxina/sangre , Tiroxina/uso terapéutico
15.
Eur J Neurosci ; 14(12): 1953-60, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11860490

RESUMEN

Glutamatergic transmission is mediated by ionotropic receptors that directly gate cationic channels and metabotropic receptors that are coupled to second messenger generating systems and to ionic channels via heterotrimeric guanine-nucleotide binding- (G) proteins. This distinction cannot be made for the ionotropic receptor subclass activated by alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA), which has been shown to be physically associated with the alpha-subunit of Gi1 protein and activates this G-protein. Here, we report that, in addition to a Ca2+ influx, AMPA induces the mobilization of Ca2+ from the mitochondrial pool by reversing the mitochondrial Na+/Ca2+ exchanger in mouse neurons in primary culture. Both processes required the activation of tetrodotoxin-sensitive Na+ channels. AMPA receptor activation modified the gating properties of the Na+ channel, independently of the AMPA current, suggesting a G-protein-mediated process. Indeed, co-immunoprecipitation experiments indicated that AMPA receptor activation induced the association of Gbeta with the alpha-subunit of the Na+ channel. These results suggest that, in addition to its ionic channel function, the AMPA receptor is coupled to Na+ channels through G-proteins and that this novel metabotropic function is involved in the control of neuronal excitability.


Asunto(s)
Señalización del Calcio/fisiología , Sistema Nervioso Central/metabolismo , Proteínas de Unión al GTP Heterotriméricas/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Neuronas/metabolismo , Receptores AMPA/metabolismo , Canales de Sodio/metabolismo , Transmisión Sináptica/fisiología , Animales , Calcio/metabolismo , Señalización del Calcio/efectos de los fármacos , Células Cultivadas , Agonistas de Aminoácidos Excitadores/farmacología , Antagonistas de Aminoácidos Excitadores/farmacología , Femenino , Feto , Proteínas de Unión al GTP Heterotriméricas/efectos de los fármacos , Inmunohistoquímica , Potenciales de la Membrana/efectos de los fármacos , Potenciales de la Membrana/fisiología , Ratones , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Canal de Sodio Activado por Voltaje NAV1.1 , Proteínas del Tejido Nervioso/efectos de los fármacos , Inhibición Neural/efectos de los fármacos , Inhibición Neural/fisiología , Embarazo , Receptores AMPA/efectos de los fármacos , Canales de Sodio/efectos de los fármacos , Intercambiador de Sodio-Calcio/efectos de los fármacos , Intercambiador de Sodio-Calcio/metabolismo , Transmisión Sináptica/efectos de los fármacos , Tetrodotoxina/farmacología
16.
Appl Microbiol Biotechnol ; 53(4): 476-9, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10803906

RESUMEN

The combined effect of redox potential (RP) (from -200 to 500 mV) and pH (from 5.0 to 7.0) on the heat resistance and growth recovery after heat treatment of Escherichia coli was tested. The effect of RP on heat resistance was very different depending on the pH. At pH 6.0, there was no significant difference, whereas at pH 5.0 and 7.0 maximum resistance was found in oxidizing conditions while it fell in reducing ones. In sub-lethally heat-damaged cells, low reducing and acid conditions allowed growth ability to be rapidly regained, but a decrease in the redox potential and pH brought about a longer lag phase and a slower exponential growth rate, and even led to growth failure (pH 5.0, < or =-100 mV).


Asunto(s)
Escherichia coli/crecimiento & desarrollo , Calor , Medios de Cultivo , Concentración de Iones de Hidrógeno , Oxidación-Reducción
17.
J Bacteriol ; 182(3): 620-6, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10633094

RESUMEN

Wild-type Escherichia coli K-12 ferments glucose to a mixture of ethanol and acetic, lactic, formic, and succinic acids. In anoxic chemostat culture at four dilution rates and two different oxidoreduction potentials (ORP), this strain generated a spectrum of products which depended on ORP. Whatever the dilution rate tested, in low reducing conditions (-100 mV), the production of formate, acetate, ethanol, and lactate was in molar proportions of approximately 2.5:1:1:0.3, and in high reducing conditions (-320 mV), the production was in molar proportions of 2:0.6:1:2. The modification of metabolic fluxes was due to an ORP effect on the synthesis or stability of some fermentation enzymes; thus, in high reducing conditions, lactate dehydrogenase-specific activity increased by a factor of 3 to 6. Those modifications were concomitant with a threefold decrease in acetyl-coenzyme A (CoA) needed for biomass synthesis and a 0.5- to 5-fold decrease in formate flux. Calculations of carbon and cofactor balances have shown that fermentation was balanced and that extracellular ORP did not modify the oxidoreduction state of cofactors. From this, it was concluded that extracellular ORP could regulate both some specific enzyme activities and the acetyl-CoA needed for biomass synthesis, which modifies metabolic fluxes and ATP yield, leading to variation in biomass synthesis.


Asunto(s)
Escherichia coli/fisiología , Ácido Acético/metabolismo , Acetilcoenzima A/metabolismo , Alcohol Deshidrogenasa/metabolismo , Carbono , Dióxido de Carbono/metabolismo , Electrones , Escherichia coli/metabolismo , Etanol/metabolismo , Fermentación , Formiatos/metabolismo , Ácido Láctico/metabolismo , Modelos Químicos , NAD/metabolismo , Oxaloacetatos/metabolismo , Oxidación-Reducción , Fosfoenolpiruvato/metabolismo , Fosfoenolpiruvato Carboxilasa/metabolismo , Piruvato Quinasa/metabolismo , Ácido Succínico/metabolismo
18.
Eur J Biochem ; 262(2): 595-9, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10336647

RESUMEN

The pH homeostasis and proton-motive force (Deltap) of Escherichia coli are dependent on the surrounding oxidoreduction potential (ORP). Only the internal pH value and, thus, the membrane pH gradient (DeltapH) component of the Deltap is modified, while the membrane potential (DeltaPsi) does not change in a significant way. Under reducing conditions (Eh < 50 mV at pH 7.0), E. coli decreases its Deltap especially in acidic media (21% decrease at pH 7.0 and 48% at pH 5.0 for a 850-mV ORP decrease). Measurements of ATPase activity and membrane proton conductance (CH+m) depending on ORP and pH have shown that the internal pH decrease is due to an increase in membrane proton permeability without any modification of ATPase activity. We propose that low ORP values de-energize E. coli by modifying the thiol : disulfide balance of proteins, which leads to an increase in the membrane permeability to protons.


Asunto(s)
Escherichia coli/metabolismo , Adenosina Trifosfatasas/metabolismo , Concentración de Iones de Hidrógeno , Potenciales de la Membrana , Oxidación-Reducción , Protones
19.
Eur J Neurosci ; 10(9): 2757-67, 1998 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9758146

RESUMEN

Expression of the voltage-dependent sodium channel has been analysed in adult rat central nervous system by Northern blotting and in situ hybridization. Northern blots showed that all the territories studied express beta 2 transcripts, albeit with widely varying levels (with cerebellum >> hippocampus > brain > brainstem > spinal cord). In situ hybridization confirmed that in these structures, all the neuronal cell bodies contain beta 2 mRNA; expression was particularly high in the granule cells of the cerebellum, in both pyramidal cell layer and dentate gyrus in the hippocampus, and in spinal cord motor neurons. Northern blots also showed that RNA extracted from optic nerve and cultured cortical astrocytes contained beta 2 mRNA, while it was totally absent from sciatic nerve. In situ hybridization evidenced the presence of a numerous population of beta 2-positive cells in cerebellum white matter, spinal cord white matter, and in corpus callosum, where frontal sections showed labelled cells arranged in the chain-like or row pattern typical of interfascicular oligodendrocytes. Combination of antiglial fibrillary acid protein (GFAP) immunofluorescent histochemistry with detection of beta 2 mRNA evidenced that expression of the transcripts was indeed restricted to GFAP-negative cells in white matter.


Asunto(s)
Sistema Nervioso Central/química , Sistema Nervioso Central/citología , ARN Mensajero/biosíntesis , Canales de Sodio/genética , Animales , Animales Recién Nacidos , Astrocitos/química , Astrocitos/citología , Northern Blotting , Células Cultivadas , Cerebelo/química , Cerebelo/citología , Corteza Cerebral/química , Corteza Cerebral/citología , Cuerpo Calloso/química , Cuerpo Calloso/citología , Expresión Génica , Proteína Ácida Fibrilar de la Glía/análisis , Hipocampo/química , Hipocampo/citología , Hibridación in Situ , Vaina de Mielina/química , Neuronas/química , Neuronas/citología , Oligodendroglía/citología , ARN Mensajero/análisis , Ratas , Ratas Wistar , Sodio/metabolismo , Canales de Sodio/análisis , Médula Espinal/química , Médula Espinal/citología
20.
Surgery ; 123(6): 632-6, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9626313

RESUMEN

BACKGROUND: This work summarizes the experience obtained during 25 years in the management of intestinal perforations caused by Salmonella typhi with a directed resection and anastomosis at the General Hospital of México City. METHODS: A total of 352 cases of perforation of the ileum caused by Salmonella typhi seen during the course of 25 years were studied. Patients were divided into two groups; group A had 236 patients and group B had 116 patients. All patients underwent either conventional resection and anastomosis or primary closure (group A) or directed intestinal resection of 10 cm at each side of the perforation on the basis of anatomopathologic studies with serial sections (group B). RESULTS: Morbidity and mortality for group B were each of 1.72%, significantly lower than the 33.47% morbidity and 7.20% mortality in group A. CONCLUSIONS: Primary closure should be discouraged, even for a single perforation. Instead directed intestinal resection is recommended as elective surgery for all cases of typhoid fever complicated with intestinal perforation, resecting 10 cm at each side of the distal and proximal perforation.


Asunto(s)
Enfermedades del Íleon/cirugía , Perforación Intestinal/cirugía , Fiebre Tifoidea/complicaciones , Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
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