C. Molina

Differential expression of matrix metalloproteinases in labial salivary glands of patients with primary Sjögren's syndrome: Mechanisms of exocrine parenchyma destruction

OBJECTIVEnTo determine the enzymatic activity and cellular localization of matrix metalloproteinases (MMPs) 2, 3, and 9 in labial salivary glands from patients with different degrees of severity of primary Sjogrens syndrome (primary SS).nnnMETHODSnGelatinase activity was determined by zymography and quantified by densitometry. The specificity of MMPs was determined using protease inhibitors and chelators, as well as activators of the latent forms of these enzymes. The cellular localization of MMPs was carried out using monoclonal antibodies that recognize their latent and active forms.nnnRESULTSnLabial glands from control subjects and patients showed gelatinase activity for MMP-2 and MMP-9. Activation studies revealed that both enzymes were predominantly present in their latent forms. The highest levels of MMP-9 activity were detected in patients with severe, active, primary SS (except for patients with severe clinical symptoms for extended periods) and correlated with structural and functional glandular changes. MMP-2 activity was almost the same in patients and controls. MMPs were detected by immunolocalization only in acinar and ductal cells and were homogeneously distributed throughout patients glands. MMP-2 and MMP-9 expression paralleled their gelatinase activity. MMP-3, detectable only with immunologic methods, was absent in control subjects but abundantly expressed in patients. Importantly, MMP protein levels in acinar and ductal cells were independent of either the presence or the proximity of mononuclear infiltrate cells.nnnCONCLUSIONnMMP-3 and MMP-9 expression, as well as MMP-9 catalytic activity, were increased in tissue samples from SS patients in a manner that correlated with the severity of the disease. Most important, increased MMP activity stemmed from exocrine epithelial cells and was not due to infiltrating lymphocytes. Thus, changes in salivary glands as a consequence of proteolysis may lead to severe glandular destruction.

Guías de actuación clínica en la hemorragia intracerebral

Intracerebral haemorrhage accounts for 10%-15% of all strokes; however it has a poor prognosis with higher rates of morbidity and mortality. Neurological deterioration is often observed during the first hours after onset and determines poor prognosis. Intracerebral haemorrhage, therefore, is a neurological emergency which must be diagnosed and treated properly as soon as possible. In this guide we review the diagnostic procedures and factors that influence the prognosis of patients with intracerebral haemorrhage and we establish recommendations for the therapeutic strategy, systematic diagnosis, acute treatment and secondary prevention for this condition.

Guía para el tratamiento preventivo del ictus isquémico y AIT (I). Actuación sobre los factores de riesgo y estilo de vida

OBJECTIVEnTo update the ad hoc Committee of the Cerebrovascular Diseases Study Group of The Spanish Neurological Society guidelines on prevention of ischaemic stroke (IS) and transient ischaemic attack (TIA).nnnMETHODSnWe reviewed available evidence on risk factors and means of modifying them to prevent ischaemic stroke and TIA. Levels of evidence and recommendation grades are based on the classification of the Centre for Evidence-Based Medicine.nnnRESULTSnThis first section summarises the recommendations for action on the following factors: blood pressure, diabetes, lipids, tobacco and alcohol consumption, diet and physical activity, cardio-embolic diseases, asymptomatic carotid stenosis, hormone replacement therapy and contraceptives, hyperhomocysteinemia, prothrombotic states and sleep apnea syndrome.nnnCONCLUSIONSnChanges in lifestyle and pharmacological treatment for hypertension, diabetes mellitus and dyslipidemia, according to criteria of primary and secondary prevention, are recommended for preventing ischemic stroke.

Guía para el tratamiento preventivo del ictus isquémico y AIT (II). Recomendaciones según subtipo etiológico

BACKGROUND AND OBJECTIVEnTo update the ad hoc Committee of the Cerebrovascular Diseases Study Group of The Spanish Neurological Society guidelines on prevention of ischaemic stroke (IS) and Transient Ischaemic Attack (TIA).nnnMETHODSnWe reviewed the available evidence on ischaemic stroke and TIA prevention according to aetiological subtype. Levels of evidence and recommendation levels are based on the classification of the Centre for Evidence-Based Medicine.nnnRESULTSnIn atherothrombotic IS, antiplatelet therapy and revascularization procedures in selected cases of ipsilateral carotid stenosis (70%-90%) reduce the risk of recurrences. In cardioembolic IS (atrial fibrillation, valvular diseases, prosthetic valves and myocardial infarction with mural thrombus) prevention is based on the use of oral anticoagulants. Preventive therapies for uncommon causes of IS will depend on the aetiology. In the case of cerebral venous thrombosis oral anticoagulation is effective.nnnCONCLUSIONSnWe conclude with recommendations for clinical practice in prevention of IS according to the aetiological subtype presented by the patient.

Aberrant localization of ezrin correlates with salivary acini disorganization in Sjögren’s Syndrome

OBJECTIVESnTo analyse whether the alterations in the structure and organization of microvilli in salivary acinar cells from SS patients are linked to changes in the expression and/or cellular localization of ezrin.nnnMETHODSnSalivary gland (SG) acini from controls and SS patients were used to evaluate ezrin expression by western blot and localization of total and activated (phospho-Thr567) ezrin by IF and EM.nnnRESULTSnIn acini from control labial SGs, ezrin was located predominantly at the apical pole and to a lesser extent at the basal region of these cells. Conversely, in acini extracts from SS patients, ezrin showed significantly elevated levels, which were accompanied with localization mostly at the basal region. Moreover, F-actin maintained its distribution in both the apical region and basolateral cortex; however, it was also observed in the acinar cytoplasm. Phospho-ezrin (active form) was located exclusively at the apical pole of acinar cells from control subjects and abundantly located at the basal cytoplasm in SS samples. These results were confirmed by immunogold studies.nnnCONCLUSIONSnThe decrease of ezrin and phospho-ezrin at the apical pole and the cytoplasmic redistribution of F-actin suggest an altered interaction between the F-actin-cytoskeleton and plasma membrane in SS patient acini, which may explain the microvilli disorganization. These alterations could eventually contribute to SG hyposecretion in SS patients.

Doble inervación del músculo braquial en la población chilena

La doble inervacion del musculo braquial esta dada por el nervio musculocutaneo y por ramos provenientes del nervio radial segun lo describen algunos textos anatomicos y numerosos trabajos cientificos. Sin embargo, no existe consenso en la frecuencia con la que esta se presenta. El objetivo de este estudio es verificar la presencia y determinar la frecuencia de la contribucion del nervio radial en la inervacion del musculo braquial. En el presente trabajo se utilizaron 30 miembros superiores previamente fijados con solucion fijadora y conservadora. Se realizo diseccion de la region braquial para determinar la presencia de ramos del nervio radial inervando al musculo braquial, verificando la presencia de ramos que penetraban en el musculo y tomando muestras de estos ramos en el sitio donde perforaban al musculo para su estudio histologico. Fue posible observar la presencia de ramos del nervio radial que penetraban en el musculo braquial en un 90% de los casos; en ellos el punto motor de estos ramos se ubico siempre en el tercio distal del musculo. De acuerdo a los resultados obtenidos en el presente trabajo, la doble inervacion del musculo braquial observada por autores clasicos y reportada en estudios en diversas poblaciones, esta presente en alto porcentaje de la muestra. Estos hallazgos pueden servir de referencia para procedimientos quirurgicos, estudios electromiograficos y sonograficos.

Frequency and outcome of total anterior circulation strokes without intracranial large‐vessel occlusion

The percentage of patients with clinical total anterior circulation infarct (TACI) syndrome treated with reperfusion therapies in the absence of intracranial large‐vessel occlusion (ILVO) was determined and their characteristics and outcome are described.

Prevalence of the sternalis muscle in Chilean population: A computed tomography study

The sternalis muscle is an anatomic variation that was first described in 1604. It has been studied in different populations worldwide, showing a widespread prevalence. The clinical importance of this muscle depends on mammographic evaluation that can lead to an erroneous diagnosis of breast cancer. Our objective is to determine the prevalence of sternalis muscle in Chilean population, characterizing it by gender and side of presentation using computerized tomography. To our current knowledge, there are no studies determining its prevalence using this method. No institutional review board approval was required for this analysis, which involved data made anonymous from men and women who underwent computerized tomography imaging for diagnostic purpose between January 2012 and February 2014. A retrospective radiological identification of the sternalis muscle was performed in 2288 axial computerized tomographies to determine the overall gender and side distribution. Data were analyzed using chi-square test. The sternalis muscle was present in 20 out of 2288 computerized tomographies, and its prevalence in the Chilean population was 0.87%. This muscle was found in male (12/1064, 1.12%) and female subjects (8/1224, 0.65%), no statistical difference between genders was found. Among people with the sternalis muscle, 12 (0.52%) presented it on the left side, 6 (0.26%) on the right side, and only 2 (0.09%) had bilateral sternalis muscle. The Chilean population has the lowest prevalence of sternalis muscle ever reported.

Inervación de la Cabeza Larga del Músculo Tríceps Braquial

RESUMEN: Clásicamente, la inervación del músculo tríceps braquial se atribuye al nervio radial. Sin embargo, reportes clínicos han observado parálisis de la cabeza larga del músculo tríceps braquial posterior a lesiones del nervio axilar, ocurridas luego de una luxación de la articulación glenohumeral, poniendo en duda la inervación de la cabeza larga del músculo tríceps braquial. El objetivo del pres ente studio es verificar la inervación de la cabeza larga del músculo tríceps braquial por parte del nervio axilar. Se disecaron 12 regiones p osteri r de hombro y brazo, previamente fijadas en solución fijadora conservadora, identificando ramos de inervación del nervio axilar hacia la ca beza larga del músculo tríceps braquial, luego se obtuvieron muestras para estudio histológico con Hematoxilina-Eosina. Fue posible identifica r en todos los casos ramos del nervio axilar, penetrando en la mitad superior de la cabeza larga del músculo tríceps braquial. El estudio hist ológico mo ró una imagen compatible con tejido nervioso en todas las muestras analizadas. Estos resultados contrastan con las descripciones reali zadas n t xtos clásicos respecto a la inervación del músculo tríceps braquial, el cual podría presentar una doble inervación proveniente de lo s nervios radial y axilar, o una inervación diferente para cada cabeza. Los hallazgos presentados aportan información a la hora de analizar las le siones del n rvio axilar post luxaciones de hombro, al realizar procedimientos quirúrgicos en esta región o en la planificación de la rehabilitac ión de estos pacientes.