Diverse Inflammatory Response After Cerebral Microbleeds Includes Coordinated Microglial Migration and Proliferation.

BACKGROUND AND PURPOSE:Cerebral microbleeds are linked to cognitive decline, but it remains unclear how they impair neuronal function. Infarction is not typically observed near microbleeds, suggesting more subtle mechanisms, such as inflammation, may play a role. Because of their small size and largely asymptomatic nature, real-time detection and study of spontaneous cerebral microbleeds in humans and animal models are difficult. METHODS:We used in vivo 2-photon microscopy through a chronic cranial window in adult mice to follow the inflammatory response after a cortical microhemorrhage of ≈100 µm diameter, induced by rupturing a targeted cortical arteriole with a laser. RESULTS:The inflammatory response included the invasion of blood-borne leukocytes, the migration and proliferation of brain-resident microglia, and the activation of astrocytes. Nearly all inflammatory cells responding to the microhemorrhage were brain-resident microglia, but a small number of CX3CR1+ and CCR2+ macrophages, ultimately originating from the invasion of blood-borne monocytes, were also found near the lesion. We found a coordinated pattern of microglia migration and proliferation, where microglia within 200 µm of the microhemorrhage migrated toward the lesion over hours to days. In contrast, microglia proliferation was not observed until ≈40 hours after the lesion and occurred primarily in a shell-shaped region where the migration of microglia decreased their local density. These data suggest that local microglia density changes may trigger proliferation. Astrocytes activated in a similar region as microglia but delayed by a few days. By 2 weeks, this inflammatory response had largely resolved. CONCLUSIONS:Although microhemorrhages are small in size, the brain responds to a single bleed with an inflammatory response that involves brain-resident and blood-derived cells, persists for weeks, and may impact the adjacent brain microenvironment

Adaptive Navigation Control for Swarms of Autonomous Mobile Robots

This paper was devoted to developing a new and general coordinated adaptive navigation scheme for large-scale mobile robot swarms adapting to geographically constrained environments. Our distributed solution approach was built on the following assumptions: anonymity, disagreement on common coordinate systems, no pre-selected leader, and no direct communication. The proposed adaptive navigation was largely composed of four functions, commonly relying on dynamic neighbor selection and local interaction. When each robot found itself what situation it was in, individual appropriate ranges for neighbor selection were defined within its limited sensing boundary and the robots properly selected their neighbors in the limited range. Through local interactions with the neighbors, each robot could maintain a uniform distance to its neighbors, and adapt their direction of heading and geometric shape. More specifically, under the proposed adaptive navigation, a group of robots could be trapped in a dead-end passage,but they merge with an adjacent group to emergently escape from the dead-end passage. Furthermore, we verified the effectiveness of the proposed strategy using our in-housesimulator. The simulation results clearly demonstrated that the proposed algorithm is a simple yet robust approach to autonomous navigation of robot swarms in highlyclutteredenvironments. Since our algorithm is local and completely scalable to any size, it is easily implementable on a wide variety of resource-constrained mobile robots andplatforms. Our adaptive navigation control for mobile robot swarms is expected to be used in many applications ranging from examination and assessment of hazardous environments to domestic applications

Relationships between performance and kinematic/kinetic variables of stair descent in patients with medial knee osteoarthritis: An evaluation of dynamic stability using an extrapolated center of mass

Background: The ability to descend stairs independently is impaired from a relatively early stage in patients with knee osteoarthritis. The purpose of this study was to evaluate the performance in patients with knee osteoarthritis when stepping down a step by evaluating the dynamic stability using the extrapolated center of mass. Methods: Twenty-three individuals with medial knee osteoarthritis were evaluated during step descent without any assistance. Kinematic/kinetic data were collected using a three-dimensional motion analysis system and force platforms. The extrapolated center of mass and its deviation from the anterior boundary on the base of support (margin of stability) were calculated at the initiation of descent. Joint angles and internal joint moments were collected at the stance limb. The relationship between patients' dynamic stability control, which was measured by the timed up and go test, and the length of margin of stability was analyzed. Relationships between the length of the margin of stability and each kinematic/kinetic variable were also evaluated. Findings: The margin of stability positively correlated with the time taken for a timed up and go test. A positive correlation was additionally observed between the ankle dorsiflexion angle and the margin of stability. It was also found that a higher ratio of ankle plantar flexion moment by support moment was associated with a larger margin of stability. Interpretation: Patients with knee osteoarthritis who had high ability in dynamic stability control were observed to move their center of mass anteriorly at the initiation of stepping down. It was also suggested that these patients could dorsiflex their ankle joint and generate sufficient ankle plantar flexor torque

Two Cases of Transfusion-related Acute Lung Injury Triggered by HLA and Anti-HLA Antibody Reaction

Transfusion-related acute lung injury (TRALI) is a serious adverse transfusion reaction that is presented as acute hypoxemia and non-cardiogenic pulmonary edema, which develops during or within 6 hr of transfusion. Major pathogenesis of TRALI is known to be related with anti-HLA class I, anti-HLA class II, or anti-HNA in donor's plasma. However, anti-HLA or anti-HNA in recipient against transfused donor's leukocyte antigens also cause TRALI in minor pathogenesis and which comprises about 10% of TRALI. Published reports of TRALI are relatively rare in Korea. In our cases, both patients presented with dyspnea and hypoxemia during transfusion of packed red blood cells and showed findings of bilateral pulmonary infiltrations at chest radiography. Findings of patients' anti-HLA antibodies and recipients' HLA concordance indicate that minor pathogenesis may be not as infrequent as we'd expected before. In addition, second case showed that anti-HLA class II antibodies could be responsible for immunopathogenic mechanisms, alone

Maintenance of nitric oxide inhalation to a patient with hemoperitonium and acute respiratory distress syndrome during anesthesia -A case report-

Inhaled nitric oxide (NO) is occasionally used to treat hypoxemia for patients with acute respiratory distress syndrome (ARDS) in the intensive care unit (ICU). However, it is controversial whether or not to maintain inhalation of NO during general anesthesia because of complications, such as nitrogen dioxide (NO2) production, methemoglobinemia, and inhibition of platelet aggregation. In this case, a 67-year-old male fell from a roof and was brought to an emergency care center. During management, he vomited gastric contents and aspirated. In spite of tracheal intubation and mechanical ventilation with high oxygen therapy, the hypoxia did not improve. NO inhalation with mechanical ventilation was performed to treat hypoxemia due to ARDS in the ICU. We maintained the NO inhalation during the surgery for a hemoperitonium. The surgery was completed without intra-operative hemodynamic instability or any complications

Primary Pancreatic Lymphoma in Korea-A Single Center Experience

The aim of this study was to report a single center experience of primary pancreatic lymphoma (PPL) in Korea. We analyzed the clinicopathological data from four PPL patients (three male, median age 36 yr) diagnosed from 1997 to 2007 at Seoul National University Hospital. The diagnoses were: diffuse large B cell lymphoma (n=2), Ki-1 (+) anaplastic large cell lymphoma (n=1), and Burkitt lymphoma (n=1). Presenting symptoms and signs were: abdominal pain (n=4), pancreatitis (n=2), weight loss (n=2) and abdominal mass (n=1). No patient underwent surgery. The Ann Arbor stages of the patients were: IEA (n=1), IIEA (n=1), and IVEB (n=2). Two patients underwent treatment. The stage IEA patient underwent chemotherapy and radiation therapy that resulted in a complete remission. The stage IVEB patient who underwent chemotherapy relapsed. This patient underwent subsequent peripheral blood stem cell transplantation and is alive at 30 months. Two patients (stages IVEB and IIEA) without treatment died at 0.8 and 7.0 months, respectively. For PPL patients, chemotherapy-based treatment, and addition of radiation therapy, if possible, may offer good prognosis

Boson Stars: Alternatives to primordial black holes?

The present surge for the astrophysical relevance of boson stars stems from the speculative possibility that these compact objects could provide a considerable fraction of the non-baryonic part of dark matter within the halo of galaxies. For a very light `universal' axion of effective string models, their total gravitational mass will be in the most likely range of \sim 0.5 M_\odot of MACHOs. According to this framework, gravitational microlensing is indirectly ``weighing" the axion mass, resulting in \sim 10^{-10} eV/c^2. This conclusion is not changing much, if we use a dilaton type self-interaction for the bosons. Moreover, we review their formation, rotation and stability as likely candidates of astrophysical importance.Comment: 14 pages, uses REVTeX, 1 postscript figur