277 research outputs found

    Dopamine D 4 Receptor-Deficient Mice Display Cortical Hyperexcitability

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    The dopamine D(4) receptor (D(4)R) is predominantly expressed in the frontal cortex (FC), a brain region that receives dense input from midbrain dopamine (DA) neurons and is associated with cognitive and emotional processes. However, the physiological significance of this dopamine receptor subtype has been difficult to explore because of the slow development of D(4)R agonists and antagonists the selectivity and efficacy of which have been rigorously demonstrated in vivo. We have attempted to overcome this limitation by taking a multidimensional approach to the characterization of mice completely deficient in this receptor subtype. Electrophysiological current and voltage-clamp recordings were performed in cortical pyramidal neurons from wild-type and D(4)R-deficient mice. The frequency of spontaneous synaptic activity and the frequency and duration of paroxysmal discharges induced by epileptogenic agents were increased in mutant mice. Enhanced synaptic activity was also observed in brain slices of wild-type mice incubated in the presence of the selective D(4)R antagonist PNU-101387G. Consistent with greater electrophysiological activity, nerve terminal glutamate density associated with asymmetrical synaptic contacts within layer VI of the motor cortex was reduced in mutant neurons. Taken together, these results suggest that the D(4)R can function as an inhibitory modulator of glutamate activity in the FC.Fil: Rubinstein, Marcelo. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular "Dr. Héctor N. Torres"; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; ArgentinaFil: Cepeda, Carlos. University of California at Los Angeles; Estados UnidosFil: Hurst, Raymond S.. University of California at Los Angeles; Estados UnidosFil: Flores Hernandez, Jorge. University of California at Los Angeles; Estados UnidosFil: Ariano, Marjorie A.. The Chicago Medical School; Estados UnidosFil: Falzone, Tomas Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular "Dr. Héctor N. Torres"; ArgentinaFil: Kozell, Laura B.. Oregon Health Sciences University; Estados UnidosFil: Meshul, Charles K.. Oregon Health Sciences University; Estados UnidosFil: Bunzow, James R.. Oregon Health Sciences University; Estados UnidosFil: Low, Malcolm J.. Oregon Health Sciences University; Estados UnidosFil: Levine, Michael S.. University of California at Los Angeles; Estados UnidosFil: Grandy, David K.. Oregon Health Sciences University; Estados Unido

    Statistical Distributions of Lightning Currents Associated With Upward Negative Flashes Based on the Data Collected at the Säntis Tower in 2010 and 2011

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    This paper presents statistical distributions of lightning current parameters based on the lightning current and current-derivative waveforms measured at the Säntis Tower site in 2010 and 2011. The total number of flashes analyzed in this study was 167, which includes nearly 2000 pulses. The statistical distributions refer to upward negative flashes. It is shown that negative flashes are mainly concentrated in the summer months during the convective season. Statistical data on the salient lightning current parameters, namely, peak current, peak current derivative, risetime, pulse charge, pulse duration, interpulse interval, and flash multiplicity are presented and discussed. The obtained data that constitute the largest dataset available to this date for upward negative flashes are also compared with other available statistical distributions

    A survey on wireless ad hoc networks

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    A wireless ad hoc network is a collection of wireless nodes that can dynamically self-organize into an arbitrary and temporary topology to form a network without necessarily using any pre-existing infrastructure. These characteristics make ad hoc networks well suited for military activities, emergency operations, and disaster recoveries. Nevertheless, as electronic devices are getting smaller, cheaper, and more powerful, the mobile market is rapidly growing and, as a consequence, the need of seamlessly internetworking people and devices becomes mandatory. New wireless technologies enable easy deployment of commercial applications for ad hoc networks. The design of an ad hoc network has to take into account several interesting and difficult problems due to noisy, limited-range, and insecure wireless transmissions added to mobility and energy constraints. This paper presents an overview of issues related to medium access control (MAC), routing, and transport in wireless ad hoc networks and techniques proposed to improve the performance of protocols. Research activities and problems requiring further work are also presented. Finally, the paper presents a project concerning an ad hoc network to easily deploy Internet services on low-income habitations fostering digital inclusion8th IFIP/IEEE International conference on Mobile and Wireless CommunicationRed de Universidades con Carreras en Informática (RedUNCI

    Cross-Boundary Coordination Under Organizational Stress: Communication Patterns and Resilience

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    Coordination is one of the key activities that organizations must carry out on a day-to-day basis to maintain reliable performance in the face of changing conditions. When organizations come under stress it is important that they continue to maintain high levels of coordination. Yet extensive evidence suggests that organizations and individuals within them respond differently to stress, in ways that are sometimes functional and sometimes dysfunctional. We study the Continental air control tower in Newark that was built to co-locate representatives from key airline functions and key external parties in order to facilitate communication among them. Initial research was based on informal interviews and site visits, as well as secondary analysis of company documents and industry reports. In addition, using communication network data, we explore how cross-boundary coordination occurs under conditions of predictable and unpredictable stress, and how co-location can facilitate adaptation to changing conditions

    Cirurgia colorretal laparoscópica mão assistida: experiência com uma técnica original

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    INTRODUCCION: Hand-assisted laparoscopic colorectal surgery (HALS) is an alternative to straight laparoscopic approach (SL) that requires the use of a specific device to maintain the pneumoperitoneum. Our group has described an original double glove technique to replace it. Our purpose was to compare perioperative outcomes of patients undergoing HALS using this original technique vs SL. METHODS: Retrospective review of a prospective database including patients who underwent elective laparoscopic colorectal resections between 2004 to 2020 at the Hospital Italiano, Argentina. Logistic regression analysis, propensity score matching, and inverse probability weighting were used to estimate adjusted treatment effects for perioperative outcomes. RESULTS: HALS (n=458) and SL (n=1692) cases were demographically similar. HALS was associated with a shorter operative time (170.3 vs 206.9 minutes, p<0.001). Such difference was even more pronounced in obese (44.1 min), large patients (37.5 min), complex procedures (33.8 min) and surgeries carried out by non-trained surgeons (57,6 vs 31,6 minutes, p<0.001). Hand-assisted was associated with a lower conversion rate (5% vs 9.9%, p<0.001) with an adjusted odds ratio of 0.45 (95%CI 0.28-0.73). No difference in hospital stay, morbidity, and readmission rates was found. CONCLUSIONS: HALS with double-glove technique is comparable to SL in terms of postoperative outcomes keeping reduced operative time and conversion rates, especially in obese patients undergoing complex procedures.    INTRODUCCIÓN: La cirugía colorrectal laparoscópica mano asistida (CLMA) es un abordaje alternativo a la laparoscopia directa (LD) que requiere de un dispositivo específico para mantener el neumoperitoneo. Nuestro grupo describió una técnica original de doble guante como alternativa a este dispositivo. El objetivo del presente trabajo fue analizar los resultados de esta técnica comparándola con la técnica de LD.  MÉTODOS: Se analizó una serie consecutiva de pacientes sometidos a cirugías colorrectales laparoscópicas entre 2004 y 2020 en el Hospital Italiano de Bs, As, Argentina. Se realizó un modelo de regresión múltiple de selección progresiva y apareamiento por puntaje de propensión para analizar los resultados perioperatorios. RESULTADOS: Los casos de CLMA (n=458) y LD (n=1692) fueron demográficamente similares. CLMA se asoció a un menor tiempo operatorio (170,3 vs 206,9 minutos, p<0.001). Dicha reducción fue más marcada en obesos (44.1 min), pacientes grandes (37.5 min), cirugías complejas (33.8 min) y en procedimientos realizados por cirujanos no entrenados (57,6 vs 31,6 minutos, p<0.001). CLMA resultó tener menor índice de conversión (5% vs 9.9%, p<0.001) con una razón de probabilidades ajustada de 0,45. No se hallaron diferencias en cuanto a estadía hospitalaria, morbimortalidad y readmisión. CONCLUSIÓN: CLMA con doble guante es comparable a la LD manteniendo un tiempo operatorio reducido y bajo índice de conversión, particularmente en pacientes obesos sometidos a procedimientos complejos.   INTRODUÇÃO: A cirurgia colorretal laparoscópica assistida pela mão (CLMA) é uma abordagem alternativa para a laparoscopia direta (LD) que requer um dispositivo específico para manter o pneumoperitônio. Nosso grupo descreveu uma técnica original de luva dupla como alternativa a esse dispositivo. O objetivo do presente trabalho foi analisar os resultados desta técnica comparando-a com a técnica LD. MÉTODOS: Uma série consecutiva de pacientes submetidos a cirurgias colorretais laparoscópicas entre 2004 e 2020 no Hospital Italiano de Bs, As, Argentina foi analisada. Um modelo de regressão múltipla de seleção progressiva e correspondência de escore de propensão foi realizado para analisar os resultados perioperatórios. RESULTADOS: Os casos de CLMA (n = 458) e LD (n = 1692) foram demograficamente semelhantes. CLMA foi associado a um tempo operatório mais curto (170,3 vs 206,9 minutos, p <0,001). Essa redução foi mais acentuada em obesos (44,1 min), pacientes grandes (37,5 min), cirurgias complexas (33,8 min) e em procedimentos realizados por cirurgiões não treinados (57,6 vs 31,6 minutos, p <0,001). CLMA acabou tendo uma taxa de conversão mais baixa (5% vs 9,9%, p <0,001) com um odds ratio ajustado de 0,45. Não foram encontradas diferenças em termos de internação, morbimortalidade e readmissão. CONCLUSÃO: CLMA com luvas duplas é comparável ao LD, mantendo um tempo operatório reduzido e uma baixa taxa de conversão, principalmente em pacientes obesos submetidos a procedimentos complexos.

    R-Spondin3 is associated with basal-progenitor behavior in normal and tumor mammary cells

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    R-spondin3 (RSPO3) is a member of a family of secreted proteins that enhance Wnt signaling pathways in diverse processes, including cancer. However, the role of RSPO3 in mammary gland and breast cancer development remains unclear. In this study, we show that RSPO3 is expressed in the basal stem cell–enriched compartment of normal mouse mammary glands but is absent from committed mature luminal cells in which exogenous RSPO3 impairs lactogenic differentiation. RSPO3 knockdown in basal-like mouse mammary tumor cells reduced canonical Wnt signaling, epithelial-to-mesenchymal transition-like features, migration capacity, and tumor formation in vivo. Conversely, RSPO3 overexpression, which was associated with some LGR and RUNX factors, highly correlated with the basal-like subtype among patients with breast cancer. Thus, we identified RSPO3 as a novel key modulator of breast cancer development and a potential target for treatment of basal-like breast cancers. Significance: These findings identify RSPO3 as a potential therapetuic target in basal-like breast cancers. Graphical Abstract: http://cancerres.aacrjournals.org/content/canres/78/16/4497/F1.large.jpg.Fil: Tocci, Johanna Melisa. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Fisiología, Biología Molecular y Neurociencias. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Fisiología, Biología Molecular y Neurociencias; ArgentinaFil: Felcher, Carla María. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Fisiología, Biología Molecular y Neurociencias. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Fisiología, Biología Molecular y Neurociencias; ArgentinaFil: Garcia Sola, Martin Emilio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Fisiología, Biología Molecular y Neurociencias. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Fisiología, Biología Molecular y Neurociencias; ArgentinaFil: Goddio, Maria Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Fisiología, Biología Molecular y Neurociencias. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Fisiología, Biología Molecular y Neurociencias; ArgentinaFil: Zimberlin, Maria Noel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Fisiología, Biología Molecular y Neurociencias. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Fisiología, Biología Molecular y Neurociencias; ArgentinaFil: Rubinstein, Natalia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Fisiología, Biología Molecular y Neurociencias. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Fisiología, Biología Molecular y Neurociencias; ArgentinaFil: Srebrow, Anabella. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Fisiología, Biología Molecular y Neurociencias. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Fisiología, Biología Molecular y Neurociencias; ArgentinaFil: Coso, Omar Adrian. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Fisiología, Biología Molecular y Neurociencias. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Fisiología, Biología Molecular y Neurociencias; ArgentinaFil: Abba, Martín Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Fisiología, Biología Molecular y Neurociencias. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Fisiología, Biología Molecular y Neurociencias; ArgentinaFil: Meissl, Roberto Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Fisiología, Biología Molecular y Neurociencias. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Fisiología, Biología Molecular y Neurociencias; ArgentinaFil: Kordon, Edith Claudia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Fisiología, Biología Molecular y Neurociencias. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Fisiología, Biología Molecular y Neurociencias; Argentin

    A survey on wireless ad hoc networks

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    A wireless ad hoc network is a collection of wireless nodes that can dynamically self-organize into an arbitrary and temporary topology to form a network without necessarily using any pre-existing infrastructure. These characteristics make ad hoc networks well suited for military activities, emergency operations, and disaster recoveries. Nevertheless, as electronic devices are getting smaller, cheaper, and more powerful, the mobile market is rapidly growing and, as a consequence, the need of seamlessly internetworking people and devices becomes mandatory. New wireless technologies enable easy deployment of commercial applications for ad hoc networks. The design of an ad hoc network has to take into account several interesting and difficult problems due to noisy, limited-range, and insecure wireless transmissions added to mobility and energy constraints. This paper presents an overview of issues related to medium access control (MAC), routing, and transport in wireless ad hoc networks and techniques proposed to improve the performance of protocols. Research activities and problems requiring further work are also presented. Finally, the paper presents a project concerning an ad hoc network to easily deploy Internet services on low-income habitations fostering digital inclusion8th IFIP/IEEE International conference on Mobile and Wireless CommunicationRed de Universidades con Carreras en Informática (RedUNCI

    Acute mesenteric ischemia : guidelines of the World Society of Emergency Surgery

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    Acute mesenteric ischemia (AMI) is typically defined as a group of diseases characterized by an interruption of the blood supply to varying portions of the small intestine, leading to ischemia and secondary inflammatory changes. If untreated, this process will eventuate in life threatening intestinal necrosis. The incidence is low, estimated at 0.09-0.2% of all acute surgical admissions. Therefore, although the entity is an uncommon cause of abdominal pain, diligence is always required because if untreated, mortality has consistently been reported in the range of 50%. Early diagnosis and timely surgical intervention are the cornerstones of modern treatment and are essential to reduce the high mortality associated with this entity. The advent of endovascular approaches in parallel with modern imaging techniques may provide new options. Thus, we believe that a current position paper from World Society of Emergency Surgery (WSES) is warranted, in order to put forth the most recent and practical recommendations for diagnosis and treatment of AMI. This review will address the concepts of AMI with the aim of focusing on specific areas where early diagnosis and management hold the strongest potential for improving outcomes in this disease process. Some of the key points include the prompt use of CT angiography to establish the diagnosis, evaluation of the potential for revascularization to re-establish blood flow to ischemic bowel, resection of necrotic intestine, and use of damage control techniques when appropriate to allow for re-assessment of bowel viability prior to definitive anastomosis and abdominal closure.Peer reviewe
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