sábado, 23 de julio de 2011

cancer de pulmon en uptodate n° 2

Overview of the initial evaluation, treatment and prognosis of lung cancer
 
Author
David E Midthun, MD Section Editor
James R Jett, MD Deputy Editor
Michael E Ross, MD 



Last literature review version 18.2: May 2010 | This topic last updated: May 6, 2010 (More)


INTRODUCTION — Lung cancer is the most common cause of cancer mortality worldwide for both men and women, causing approximately 1.2 million deaths per year [1]. In the United States, in 2009, there will have been an estimated 219,000 new cases of lung cancer and 159,000 deaths [2]. In contrast, colorectal, breast, and prostate cancers combined will have been responsible for only 118,000 deaths.

Both the absolute and relative frequency of lung cancer have risen dramatically. As an example, the age-adjusted death rates from lung cancer were similar to that of pancreatic cancer prior to 1930 for men and prior to 1960 for women (figure 1 and figure 2) [2]. Around 1953, lung cancer became the most common cause of cancer deaths in men, and in 1985 it became the leading cause of cancer deaths in women. Although lung cancer deaths have begun to decline in men, the death rate in women continues to rise, and almost one-half of all lung cancer deaths now occur in women. (See "Women and lung cancer".)

The term lung cancer, or bronchogenic carcinoma, refers to malignancies that originate in the airways or pulmonary parenchyma. Approximately 95 percent of all lung cancers are classified as either small cell lung cancer (SCLC) or non-small cell lung cancer (NSCLC). This distinction is required for staging, treatment, and prognosis. Other cell types comprise about 5 percent of malignancies arising in the lung.

This discussion will present an overview of diagnosis, treatment and prognosis of patients with NSCLC and SCLC. An overview of the risk factors, pathology, and clinical manifestations of lung cancer is presented separately. (See "Overview of the risk factors, pathology, and clinical manifestations of lung cancer".)

INITIAL EVALUATION — The three main issues to assess in a patient with a suspected lung cancer are the cell type (NSCLC versus SCLC), the stage of disease, and the functional status of the patient. These parameters are essential for appropriate patient management.



 • Whether a lung cancer is a NSCLC or an SCLC is critical for treatment planning, and a tissue diagnosis is necessary.

 • Staging for NSCLC is critical in determining the appropriate treatment for a patient with resectable disease and avoiding unnecessary surgery in advanced disease [3]. Staging of NSCLC utilizes the tumor, node, metastasis (TNM) system (table 1 and table 2 and table 3). (See "Diagnosis and staging of non-small cell lung cancer" and "Tumor node metastasis (TNM) staging system for non-small cell lung cancer".)

 • Staging of SCLC uses the Veterans Administration Lung Study Group designations of limited (confined to one hemithorax) or extensive (beyond one hemithorax) disease [4]. This distinction is important since patients with limited disease may benefit from thoracic radiation therapy in addition to systemic chemotherapy. (See "Pathobiology and staging of small cell carcinoma of the lung".)

 • Treatment of lung cancer, whether with surgery, chemotherapy, radiation therapy or a combination of these, can be associated with substantial toxicity. Patients with significant impairment due to their lung cancer or comorbid conditions may not be able to withstand resection or alternatively aggressive chemoradiotherapy. Performance status can be assessed by a variety of methods including the Karnofsky Performance Status (KPS) and the Eastern Cooperative Oncology Group Performance Scale (ECOG PS) (table 4 and table 5). The KPS was introduced in the 1940s and uses a 100-point scale and 11 measures to describe patient's abilities to pursue activities and perform work [5]. The ECOG PS uses a five-point scale and has been shown in a comparative study to be a better predictor of prognosis [6].

Diagnostic procedures and staging should be carried out simultaneously, even though it may be tempting to simply pursue a diagnosis when an obvious abnormality is present on imaging. As an example, in a patient with a 4 cm lung mass and mediastinal adenopathy on CT, a mediastinal node biopsy may provide a diagnosis and confirm N2 (IIIA) disease (figure 3A-B). In contrast, a transthoracic needle aspirate of the mass may provide a tissue diagnosis but does not stage the mediastinum. This can lead to the inappropriate assumption that mediastinal lymph nodes are involved or necessitate a second procedure. (See "Diagnosis and staging of non-small cell lung cancer" and "Tumor node metastasis (TNM) staging system for non-small cell lung cancer".)

NSCLC

Treatment — Surgical resection offers the best opportunity for long-term survival and cure in patients with resectable NSCLC. The appropriateness of surgical resection of candidates with known or suspected NSCLC includes preoperative staging and an assessment of performance status with concurrent comorbidities and pulmonary function to allow prediction of postoperative function.

A patient with lung cancer may be "resectable" by virtue of having a surgically removable NSCLC, but may not be "operable" due to poor pulmonary function or comorbidities. Advances in surgical technique, the role of limited resection, and postoperative care may provide the opportunity for surgical resection in patients who previously might not have been considered candidates for aggressive treatment. (See "Preoperative evaluation for lung resection".)



 • Patients with stage I or II NSCLC should be treated with complete surgical resection whenever possible (figure 4). Postoperative adjuvant chemotherapy has been shown to improve survival in patients with pathologic stage II disease and may have a role for patients with stage IB NSCLC (table 1). (See "Management of stage I and stage II non-small cell lung cancer" and "Adjuvant systemic therapy in resectable non-small cell lung cancer".)

 • Patients with stage I or II disease who are not candidates for surgical resection or who refuse surgery may be candidates for radiotherapy. Radiotherapy may be applied by conventional means, stereotactic radiosurgery, or radiofrequency ablation. Photodynamic therapy may also be useful as a primary treatment modality in carefully selected patients with superficial airway lesions (figure 4). (See "Management of stage I and stage II non-small cell lung cancer", section on 'Nonsurgical approaches' and "Photodynamic therapy of lung cancer".)

 • For patients with pathologically proven stage III disease prior to definitive therapy, a combined modality approach using concurrent chemotherapy is generally preferred. The role of surgery following chemoradiotherapy is an area of active investigation. Surgery may also retain a role for carefully selected patients with T3 or T4 lesions and negative mediastinal lymph nodes. (See "Management of stage III non-small cell lung cancer".)

 • In patients with clinical stage I or II disease, in whom tumor involvement of mediastinal lymph nodes (pathologic stage IIIA) is documented in the histologic evaluation of the surgical resection specimen, adjuvant chemotherapy has been shown to improve survival. (See "Adjuvant systemic therapy in resectable non-small cell lung cancer".)

 • Patients with stage IV disease are generally treated with systemic therapy or a symptom-based palliative approach. In appropriately selected patients, chemotherapy and/or molecularly targeted therapy may prolong survival without sacrificing quality of life. Radiation therapy and surgery may also be useful for symptom palliation in some patients. (See "Overview of the treatment of advanced non-small cell lung cancer".)

 • Patients with stage IV disease based upon the presence of an isolated metastasis (eg, brain, adrenal) may benefit from resection of the metastasis as well as aggressive treatment of the primary tumor [7]. (See "Treatment of brain metastases in favorable prognosis patients".)

 • Local palliative measures may be useful in patients with uncontrolled pulmonary disease [8]. Dyspnea due to bulky central airway involvement may be palliated by rigid or flexible bronchoscopic removal of tumor using laser for coagulation or cryotherapy. Stenting may be necessary to maintain airway patency and allow external beam radiation. Brachytherapy can be applied locally by a bronchoscopy-directed catheter placement and may be helpful for recurrent or persistent disease in the airway. This approach is usually pursued after maximal external beam radiation. (See "Diagnosis and management of central airway obstruction".)

Prognosis of NSCLC

Stage of disease — The TNM stage at presentation in patients with NSCLC has the greatest impact on the prognosis.

The most extensive data relating stage to prognosis come from a validation series of over 31,000 cases from the Surveillance, Epidemiology and End Results (SEER) database used to validate the 7th TNM staging system (table 1) [9]. Survival decreased progressively with more advanced disease from a median of 59 months for patients with stage IA disease to four months for those with stage IV disease (figure 5). (See "Diagnosis and staging of non-small cell lung cancer" and "Tumor node metastasis (TNM) staging system for non-small cell lung cancer".)

Clinical parameters — Other clinical factors that exist at the time of diagnosis that can predict survival independent of the disease stage. Most of these factors were identified in studies that primarily included patients with advanced or inoperable NSCLC:



 • Performance status — Poor performance status and weight loss have been associated with shortened survival [10-15]. Reduced appetite, a precursor of weight loss, also has negative prognostic implications [10].

 • Ethnicity — African American ethnicity does not appear to be an independent predictor of poorer survival. Although some studies suggested that African Americans have a worse prognosis even after correcting for stage and treatment, a multivariate analysis indicated that performance status and weight loss account for these results [11].

Pathologic and molecular factors — Older studies of patients with NSCLC have given conflicting results as to whether the distinction between adenocarcinoma and squamous cell carcinoma affects prognosis [16-20]. Other pathologic factors that have been linked to prognosis in some studies include the degree of differentiation [21,22] and lymphatic invasion [23-26]. (See "Pathology of lung malignancies".)

Each histologic subtype can vary in its degree of differentiation. The impact of tumor differentiation on resectable NSCLC is uncertain. Some studies indicate that poorly differentiated tumors have a worse prognosis than better differentiated tumors [21,22]. However, this finding has not been universal [18].

Lymphatic vessel invasion has a negative impact on outcome [23-25]. In one study of 244 patients who had resected stage I NSCLC, five-year cancer-free survival was higher among patients without lymphatic vessel invasion (74 versus 54 percent) [24]. In contrast, the prognostic significance of blood vessel invasion is uncertain, with only some studies demonstrating a negative impact on outcome [21,22,24-26].

Occult lymph node metastasis (ie, micrometastasis) can be identified by using reverse transcriptase polymerase chain reaction (RT-PCR) to detect tumor markers in lymph nodes from patients with NSCLC [27]. However, such studies are limited by lack of laboratory standardization and reproducibility. The clinical significance of such findings will remain uncertain until long-term studies are reported.

No single molecular marker has been identified that consistently predicts outcome. However, early data from gene expression profiling is promising. (See "Adjuvant systemic therapy in resectable non-small cell lung cancer", section on 'Molecular markers' and "Overview of gene expression profiling and proteomics in clinical oncology".)

PET and PET-CT — Positron emission tomography (PET), alone or integrated with computed tomography (CT), is useful in the initial staging to identify sites of tumor involvement. Integrated PET-CT has been shown to improve staging over PET scanning alone [28]. (See "Role of imaging in the staging of non-small cell lung cancer", section on 'Positron emission tomography'.)

A tumor's metabolic activity can be measured using the standardized uptake value (SUV) to assess the tumor uptake of fluorodeoxyglucose. A meta-analysis, based upon 21 retrospective studies that included 2637 patients with stages I to IV NSCLC, found that a high SUV was associated with a poor prognosis [29]. A second meta-analysis, limited to patients with stage I NSCLC, also found that a lower FDG uptake was associated with a better prognosis [30]. PET (or PET-CT) may also be useful in predicting response to chemotherapy [31-33].

Additional studies are needed to establish the role of SUV as a prognostic tool or in predicting the response to treatment.

Recurrence after complete resection — Patients who undergo a complete resection for NSCLC may develop recurrent and/or metastatic disease. Multiple factors influence survival following disease recurrence.

In a series of 1073 patients who underwent a complete resection, recurrent NSCLC was identified in 445 patients (41 percent) [34]. The median time to recurrence following surgery was 11.5 months, and the median survival following recurrence was 8.1 months. Multivariate analysis identified several factors that predicted shorter survival following recurrence. These included poor performance status, disease-free interval of one year or less, prior use of neoadjuvant chemotherapy or adjuvant radiation therapy, and distant metastases (as opposed to intrathoracic recurrence alone).

SCLC

Treatment — SCLC is a disseminated disease in most patients, even at presentation. Thus systemic chemotherapy is an integral part of the initial treatment.



 • Patients with limited stage disease are primarily treated with a combination of chemotherapy and radiation therapy, since the addition of radiation therapy has been shown to prolong survival compared to chemotherapy therapy alone. Surgery is not used except in the rare patient who presents with a solitary pulmonary nodule without metastases or regional lymph node involvement. (See "Thoracic radiotherapy in the treatment of limited stage small cell lung cancer" and "First-line chemotherapy for small cell lung cancer" and "Role of surgery in multimodality therapy for small cell lung cancer".)

 • For patients with extensive stage SCLC, chemotherapy alone is used as the initial therapy. (See "First-line chemotherapy for small cell lung cancer".)

 • Prophylactic radiation has been shown to decrease the incidence of brain metastases and prolong survival in patients with both limited and extensive stage SCLC who respond to their initial treatment. (See "Prophylactic cranial irradiation for patients with small cell lung cancer".)

Prognosis — The most important prognostic factor in patients with lung cancer is the stage of disease at presentation. The primary determinant of survival in patients with SCLC is the extent of disease at presentation. For patients with limited stage disease, median survivals range from 15 to 20 months, and the reported five-year survival rate is 10 to 13 percent. In contrast, for patients with extended stage disease, the median survival is 8 to 13 months, and the five-year survival rate is 1 to 2 percent. (See "First-line chemotherapy for small cell lung cancer", section on 'Benefit of therapy'.)

Clinical parameters also have prognostic importance in patients with SCLC [15]. Poor performance status and/or weight loss have been associated with shortened survival.

SIDE EFFECTS OF TREATMENT — Both curative and palliative treatment of lung cancer often involve multimodality approaches that may include surgery, radiation therapy, and systemic therapy with cytotoxic chemotherapy or molecularly targeted agents. (See 'SCLC' above.)

The side effects of systemic therapy are often of particular concern, because of their potential negative effects on quality of life both during and after treatment. The toxicities will vary depending upon the therapeutic regimen.

Common toxicities observed in patients being treated for lung cancer include the following:



 • Chemotherapy-induced nausea and vomiting of variable severity may be seen with most chemotherapy regimens (table 6), but can usually be prevented or managed effectively with aggressive therapy. (See "Pathophysiology and prediction of chemotherapy-induced nausea and vomiting" and "Prevention and treatment of chemotherapy-induced nausea and vomiting".)

 • Hematologic toxicity, including in particular anemia and neutropenia with an increased risk of infection, is seen with most cytotoxic chemotherapy regimens. (See "Hematologic consequences of malignancy: Anemia".)

 • Nephrotoxicity, especially with chemotherapy regimens containing cisplatin, can be severe. Intensive hydration is required to prevent this complication. (See "Cisplatin nephrotoxicity".)

 • Neurotoxicity, which is especially frequent with cisplatin and the taxanes (paclitaxel, docetaxel), is usually at least partially reversible after therapy is discontinued. (See "Neurologic complications of non-platinum cancer chemotherapy" and "Neurologic complications of platinum-based chemotherapy".)

 • Cutaneous toxicity, manifested as an acneiform rash, is frequent with erlotinib and gefitinib. Although this side effect is troublesome, the presence of a rash is correlated with a response to therapy. (See "Cutaneous complications of molecularly targeted therapy and other biologic agents used for cancer therapy", section on 'EGFR signal transduction inhibitors' and "Small molecule epidermal growth factor receptor inhibitors for advanced non-small cell lung cancer".)

 • Fatigue is frequent and may be due to systemic chemotherapy, radiation therapy, or the cancer itself. (See "Cancer-related fatigue: Prevalence, screening and clinical assessment".)

 • Anorexia and weight loss are common in patients with lung cancer, and may be due to the disease or its treatment. (See "Clinical features and pathogenesis of cancer cachexia" and "Pharmacologic management of cancer anorexia/cachexia".)

INFORMATION FOR PATIENTS — Educational materials on this topic are available for patients. (See "Patient information: Lung cancer risks, symptoms, and diagnosis".) We encourage you to print or e-mail this topic, or to refer patients to our public web site www.uptodate.com/patients, which includes this and other topics.

SUMMARY — Lung cancer is the most common cause of cancer mortality worldwide for both men and women.



 • The initial stage in management is to assess whether the patient has a NSCLC or a SCLC, the stage of the disease, and the overall performance status of the patient. (See 'Initial evaluation' above.)

 • For patients with NSCLC, management is largely determined by the stage of disease. For patients with early stage disease, surgical resection offers the best opportunity for cure, while concurrent chemoradiotherapy is preferred for those with more extensive intrathoracic disease. In contrast, patients with advanced disease are managed palliatively with systemic therapy and/or local palliative modalities. (See 'NSCLC' above.)

 • For patients with SCLC, systemic chemotherapy is an important component of treatment, because SCLC is disseminated at presentation in almost all patients. For those with limited stage disease, thoracic radiation therapy is used in combination with chemotherapy. Prophylactic cranial irradiation is often used to decrease the incidence of brain metastases and prolong survival. (See 'SCLC' above.)

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Genética y la enfermedad de Parkinson: Revisión de actualidades

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Resumen

La Enfermedad de Parkinson (EP) se define como un desorden neurodegenerativo que surge como resultado de la pérdida de células dopaminérgicas en la sustancia pars nigra compacta. Clínicamente, la EP se caracteriza por temblor en reposo, rigidez, bradicinesia e inestabilidad postural. La EP es la forma más frecuente de parkinsonismo y el segundo desorden neurodegenerativo más frecuente, después de la enfermedad de Alzheimer. Se estima que la EP afecta de 1% a 3% de la población mayor de 60 años. La incidencia en general es de 13.4 por 100 000 personas. La EP es una enfermedad con etiología compleja en la que se requiere del efecto aditivo de factores genéticos y ambientales. A pesar de que existen formas monogénicas, se cree que la gran mayoría de los casos se deben a causas multifactoriales. Más de 10 loci han sido relacionados con la EP y se han logrado definir patrones de herencia dominantes y recesivos según el gen implicado así como el cuadro clínico asociado. Este conocimiento ha permitido mayor comprensión acerca de la fisiopatología del padecimiento explicando la existencia de daño neuronal, muerte de neuronas dopaminérgicas, daño por estrés oxidativo, daño por acumulación de sustancias tóxicas, entre otras. Aun así, los conocimientos genéticos actuales permiten explicar poco menos de 10% de todos los casos de EP y es por eso de gran importancia brindar asesoramiento genético individualizado tanto al paciente como a sus familiares. La genética médica proporciona un campo amplio de investigación al respecto de esta enfermedad neurodegenerativa, no sólo para una mejor comprensión de su patogenia sino para elucidar vías terapéuticas más eficientes y de mejor beneficio para los pacientes con EP.
Palabras clave Enfermedad de Parkinson, herencia compleja, genética, México.

Identidad aumentada y madurez como internautas: somos auténticos en las redes sociales


El caparazón: Identidad aumentada y madurez como internautas: somos auténticos en las redes sociales

Link to El caparazon


Posted: 22 Jul 2011 11:03 PM PDT
Escribiendo sobre autenticidad encuentro la investigación que os presento hoy.
Se supone muchas veces que los perfiles en redes sociales crean y comunican una imagen idealizada de nosotros mismos (Manago, Graham, Greenfield, & Salimkhan, 2008), que de algún modo fingimos en internet lo que no somos.  De acuerdo con esta hipótesis sobre la identidad virtual idealizada, los propietarios de perfiles reflejan características idealizadas, que no reflejarían sus personalidades reales.
La visión alternativa defiende que sí reflejamos nuestras verdaderas identidades en internet, que  las redes sociales constituyen ya parte de nuestro contexto social extendido en el que expresar características de personalidad reales, capaces de transmitir percepciones interpersonales que lo que menos queremos es que lleven a cualquier tipo de engaño.
De hecho, lo que se transmite en redes sociales es una integración de varias fuentes de información personal similares (o incluso más reveladoras) a las que compartimos en el mundo no virtual: pensamientos privados, imágenes de la cara, relatos de nuestro comportamiento social,  cosas que contienen información válida acerca de nuestra personalidad. (Ambady & Skowronski, 2008; Funder, 1999; Hall & Bernieri, 2001; Kenny, 1994; Vazire & Gosling, 2004).
Esta sería la conclusión del estudio, lógica y que concuerda con algunas intuiciones al respecto:
-Es difícil crear identidades idealizadas en el estado  actual de la web social, sobre todo si recordamos que no somos los dueños exclusivos de esta, que como dice Bauman, «La construcción de identidad implica el triple desafío (y riesgo) de confiar en uno mismo, en otros y también en la sociedad.».
-La propia relación que establecemos en internet, donde no nos vemos las caras, donde la confianza, elemento esencial en el que basar nuestros juicios y decisiones debe traducirse a lo virtual, provoca que exijamos responsabilidad sobre sus perfiles a nuestros contactos, que además pueden conversar, interactuar con nuestras auto-definiciones para también ajustarlas a la realidad.
Como escribía hace un tiempo en Cyborgs en Las Ramblas:
“el carácter textual de la comunicación en red aporta sentimientos de seguridad, de palabras que no se lleva el viento. En este tipo de interacciones, dadas las posibilidades para registrar conversaciones, se activan en mayor medida expectativas y auto exigencias de temas como la coherencia o la autenticidad de lo comunicado.
El hecho de comunicar por escrito nos confronta con cosas de nosotros mismos que no conocíamos, nos obliga y facilita (sobretodo en la comunicación asíncrona) la introspección, otra vez la coherencia, facilitando la resolución de distorsiones cognitivas (Meichenbaum y psicólogos cognitivos en general).”
Volviendo al estudio en cuestión, de  Back et al (2010),  pone a prueba ambas hipótesis, confirmando la de la extensión vital.  Los investigadores del estudio plantean que si esta es cierta, los contactos en redes sociales, observadores en el experimento, deberían ser capaces de inferir de forma precisa las características de las personalidades reales de los propietarios de perfiles en redes sociales.

transparencia

Y los resultados son claros:  se percibe la personalidad real e incluso cuando se introducen autovaloraciones de forma controlada, el efecto de la personalidad real es elevado.  No nos es fácil (ni nos gusta), ni en la vida offline ni en redes sociales virtuales, librarnos de nosotros mismos Sonrisa, sobre todo, como apuntan algunas peculiaridades del estudio, si somos extrovertidos (los resultados son similares para encuentros cara a cara) y abiertos (también con resultados similares en los entornos reales).
La precisión fue algo más baja en el caso de existir elementos de neuroticismo, lo cual es consistente con investigaciones previas, que muestran cómo el neuroticismo es difícil de detectar en todos los contextos (Funder, 1999; Kenny, 1994).

Quería dejar estos datos pero también recordar que tal vez lo que estemos observando sea efecto de la madurez, tanto de la web social, como de nuestra condición de internautas.  Ya sabéis que me siento y os siento más grandes gracias a la web social.

Del obscurantismo a una Identidad madura, transparente y aumentada
Cabe recuperar, en este sentido, la imagen que acompaña este post y que me sirve para explicar cómo vamos evolucionando hacia la sociedad de la transparencia:  la parte izquierda, cuando el perro le decía al otro perro que “nadie sabe que eres un perro en internet”, es propia de finales de los 90, de un primer momento de internet en el que percibíamos sus chats, sus mundos virtuales como juego, como mundo paralelo, como teatro (diría Goffman) y por tanto lugar seguro en el que podíamos experimentar roles o identidades ficticias.
Lo escribía en Cyborgs en las Ramblas (segunda parte del ebook que os enlazo):
Centrándonos ya en los IRC (similares a los chats) y similares, internet se convierte en un entorno de potencial liberación, en una plataforma, sociedad o escenario (Goffman) que contiene, dentro de su complejidad, tanto los deseos como las satisfacciones idóneas para tipos múltiples de individuos. Así, valiéndome de la metáfora psicoanalítica, la red resulta un lugar de ensueño, de alucinación colectiva y no consensual (STONE, 1992), donde el yo auténtico o esencial  tiene la ocasión de desarrollarse sin la amenaza de un superego que en la red es débil y difuso (el anonimato era, sin metáfora psicoanalítica, una forma de escapar al control social).
El ego, o aquella fracción inconsciente y vencida por la sociedad en la que todos nos hemos socializado, se despereza y desmarca ahora desde el espacio de los sueños al que venía estando relegado, al nuevo territorio que la tecnología le ofrece. Así, la interacción en red se relatará en muchas ocasiones como una experiencia de Flujo (en el sentido de CSIKSZENTMUHALY, M, 1996), de estado alterado de conciencia, de fase REM (SULER y cols. 1996), de espacio lúdico-terapéutico en el que expresar y satisfacer tanto las viejas necesidades creadas durante la socialización primaria como las nuevas (Teorías sobre economía del deseo, VAN DER LEUN, 1996), surgidas en ocasiones en la propia red.

Nos situamos hoy en la parte derecha de la imagen, en la que también podríamos dibujar al perro que encabeza el post, con ropajes humanos y que ha decidido ser persona, que se ha atrevido a ser quien quiere ser en el mundo “real”.
Y es que hay mucho de empoderamiento, de aprendizaje de la diversidad, de liberación favorable a la autoexpresión, de acercamiento entre lo que queremos ser y lo que somos en realidad en el viaje que hacemos a través de la red hacia nosotros mismos, en el proceso de madurez que intento describir.  Dicho en otras palabras, la identidad del individuo conectado es aumentada, mucho más potente, como decíamos al hablar del 15M, que antes del ejercicio de auto-conocimiento, auto-expresión y auto-realización que supone una interacción en redes sociales bien aprovechada.

Nunca me atrevo a decirlo, nunca lo tengo claro pero creo que sí, que las revoluciones sociales que vivimos eran previsibles, que sintiéndonos más grandes en la web teníamos que, necesariamente, terminar por reflejarlo en el exterior. Escribía en la prehistoria de 2003:
Cada cyborg será, una vez que se integre en la nueva sociedad, mejor. ¿Control Social? ¿Reproducción de jerarquías y normas? No niego sus manifestaciones, como reproducción de los que se producen en la sociedad real y con tendencia a aumentar, conforme a la propia madurez de la red, pero lo que no puede negarse es que para entonces habremos tenido ocasión, gracias a ella, de ampliar nuestro sentido democrático, nuestro ejercicio del derecho a la libertad de expresión, de una forma a la que será difícil que podamos renunciar.

ResearchBlogging.orgBack MD, Stopfer JM, Vazire S, Gaddis S, Schmukle SC, Egloff B, & Gosling SD (2010). Facebook profiles reflect actual personality, not self-idealization. Psychological science, 21 (3), 372-4 PMID: 20424071


Posted: 22 Jul 2011 03:09 AM PDT
Os dejo la interesante entrevista que me havía ayer Blanca Salvatierra para Publico.es, con las correspondientes respuestas.
Las mias han salido hoy publicada junto a otras opiniones en un artículo llamado La maraña de las redes sociales que dejo enlazado aquí.
Con la aparición de Google+ y los rumores sobre que Microsoft está planificando su propia red social, la pregunta es ¿cuántas redes sociales puede manejar una persona sin volverse loco (Google+, Facebook, Twitter, Linkedin, etc)?
No sé si hay respuesta a cuántas redes sociales podemos manejar, más cuando evolucionarán las herramientas que unifiquen la experiencia de usuario, que permitan manejarlas todas a la vez. Lo que sí parece, según algunos estudios, es que existe un número, el denominado número de Dunbar en honor al antropólogo que lo formuló, máximo de contactos con los que podemos manejar, a nivel cognitivo, una relación significativa.
Quizás sea un número conservador y nuestros cerebros estén evolucionando con las posibilidades que van apareciendo, es pronto para medirlo, pero está claro que sí existe un límite para las relaciones más tradicionales. Otro tema es que estemos ampliando el tipo de relaciones que podemos establecer. No tiene porqué ser menos importante un contacto débil en red social virtual pero que me informa magníficamente que un vecino físico, por ejemplo.

¿Hay sitio para todas ellas o el lanzamiento de una nueva con éxito implica el comienzo del declive de otra (como en el caso de MySpace)?
Hemos pensado muchas veces que había límite pero nos han ido sorprendiendo. La sociabilidad del ser humano parece ilimitada, en número de redes y tipos de relaciones que somos capaces de establecer, inventar o reinventar.

¿Los 18 millones de usuarios que ha conseguido Google+ en tres semanas y las buenas críticas recibidas pueden hacer temblar los cimientos de la tan asentada Facebook?
Evidentemente le robarán cuota de mercado pero creo que iniciamos un largo periodo de convivencia, al estilo de lo que ocurre con los sistemas operativos (Microsoft, Apple, Linux, etc.) entre Facebook, Twitter y Plus como principales agentes mundiales.

¿Crees que es el lanzamiento definitivo para Google en cuanto a redes sociales tras el fiasco de Buzz?
Creo que es un intento fuerte, trabajado, con mayor inversión que los de Buzz o Wave pero internet es un buen lugar para el ensayo error y Google tiene muy clara la importancia del grafo social, no va a dejar de intentar conquistarlo porque sabe que es el el filtro natural de la información para el ser humano.
Otro de sus puntos fuertes de Plus que no quería dejar de observar es la polivalencia, la flexibilidad con que parece poder adaptarse a los muchos tipos de relación que podemos preferir. Pero una vez más, cada usuario decide, incluso si prefiere o se siente más seguro en redes sociales menos versátiles.

En fin… dejo contacto en Google Plus, por si os animáis.

Education review


TRAINING DAYS A video camera captures Tayo Adeeko teaching her third graders, for later critique.
Michael Nagle for The New York Times
TRAINING DAYS A video camera captures Tayo Adeeko teaching her third graders, for later critique.
New models for teacher preparation are thinking outside the box. Are they too far out?
Doctoral students at the American Museum of Natural History include Edward Stanley (with lizards), Dawn Roje (with flatfish) and Phil Barden (with ants, collected by sucking on tube).

The Critter People

Dinosaur eggs, iguanas and ooh, look, a grad student. Inside the new school at the Natural History Museum

The Master’s as the New Bachelor’s

Call it credentials inflation. A four-year degree may not cut it anymore.

For-Profit College Company Settles Whistle-Blower Suit

Kaplan Inc., which agreed Friday to settle a whistle-blower lawsuit for $1.6 million, has come under federal scrutiny over recruiting practices and students’ loan default rates.

Judge Rules Against Union on City Plan to Close Schools

New York City may proceed with plans to close 22 schools for poor performance and place 15 charter schools in the buildings of traditional schools.

Bronx Charter School Disciplined Over Admissions Methods

Academic Leadership Charter School is the first New York City charter disciplined for violating admissions rules, which require purely random selection.

Training of Teachers Is Flawed, Study Says

The National Council on Teacher Quality is drawing criticism over its plans to publish its rankings of schools of education.
FINDINGS
LIVE AND LEARN A bad fall may mean a child is less likely to have a fear of heights later in life.

Can a Playground Be Too Safe?

Efforts to regulate playground equipment to prevent injuries may stunt emotional development, a new study suggests.

School Discipline Study Raises Fresh Questions

A Texas study tracked nearly a million students from seventh grade into high school.

New Approach Proposed for Science Curriculums

A new approach for improving American science education includes focusing on core ideas and problem-solving.
Aaron Swartz, who downloaded 4.8 millions files from JSTOR, has fought against keeping scholarly material behind pay walls.

Open-Access Advocate Is Arrested for Huge Download

Harvard researcher and Internet folk hero Aaron Swartz has been arrested for allegedly hacking into networks at the Massachusetts Institute of Technology to download articles.

Geography Report Card Finds Students Lagging

Even as schools aim to better prepare students for a global work force, fewer than one in three American students are proficient in geography.
CITY ROOM

Bloomberg Pledges Money and Land for Engineering School

Signaling how serious he is about developing a high-tech university campus in New York City, the mayor said the city would provide up to $100 million and a site for a new school of engineering and applied sciences.
AWARDS From left, Shree Bose, Naomi Shah and Lauren Hodge took first prize in their age groups out of 15 finalists at the Google Science Fair.

First-Place Sweep by American Girls at First Google Science Fair

A 17-year-old from Fort Worth won the $50,000 grand prize at Google’s science fair last week.

Schools Dropping 413 From Staff

The District of Columbia public schools has sent termination notices to 413 teachers and other school employees under an evaluation system that has become a national model.
Founders of a proposed Mandarin-immersion charter school meeting in a South Orange, N.J., home. From left, Jutta Gassner-Snyder, Nancy Chu, Tom Piskula and Tiffany Boyd Hodgson.

Charter School Battle Shifts to Affluent Suburbs

Charters, normally thought of as a way to help poor areas, are being proposed in places that have good schools.

Law School Economics: Ka-Ching!

Despite fewer high-paying jobs, students continue to pour into law school. And the schools keep charging higher tuition and admitting more students.
Deutsche Bank put up 12 million euros to finance a research institute that applied advanced mathematical techniques to the world of finance, but the agreement was to be secret.

Cash Tempts the Ivory Tower’s Guardians

Two German universities secretly gave Deutsche Bank a big say at a research institute, raising eyebrows.

School Officials and Union Agree on Pilot Program for Teacher Evaluations

Teachers in 33 schools will be rated as either ineffective, developing, effective or highly effective, rather than simply satisfactory or unsatisfactory.

California to Require Gay History in Schools

California will become the first state to require public schools to include the works of gays and lesbians in social science instruction and in textbooks.
Tom Vander Ark, the former executive director of education for the Gates Foundation, says a weak economy hurt efforts by City Prep Academies to start schools in New York and New Jersey.

Tom Vander Ark’s New York-Area Charter Schools Falter

A former top official with the Gates Foundation found that opening innovative schools in the New York area was harder than he had anticipated.
EDUCATION LIFE
Beyond the B.A.
With more Americans than ever in grad school, a special issue devoted to all things postgraduate.
From Opinion
ROOM FOR DEBATE

The Case Against Law School

Should the standard three-year law school model, followed by passage of the bar exam, be the only path to a legal career?
Sunday Magazine
FIRST

No, Seriously: No Excuses

What the education-reform movement needs to do next.
Multimedia
New York School Test Scores
A complete summary of demographics and student performance over the past decade for every school in New York.
Multimedia
Timeline: Dennis M. Walcott
The life and career of the new chancellor for New York City schools.

Michael Winerip

“On Education” looks beyond the discourse to the teachers, principals and students at the heart of learning.

The Motherlode

Lisa Belkin writes about homework, friends, grades, bullying, baby sitters, the work-family balance and much more.