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Background: There is no consensus regarding the choice of anesthetic method for patients with pulmonary hypertension (PH). We report two cases in which neuraxial anesthesia was safely performed without general anesthesia during open abdominal surgery in patients with severe PH. Case presentation: Case 1: A 59-year-old woman had an atrial septal defect and a huge abdominal tumor with a mean pulmonary arterial pressure (PAP) of 39 mmHg and pulmonary vascular resistance (PVR) of 3.5 Wood units. Case 2: A 23-year-old woman who had hereditary pulmonary artery hypertension (mean PAP, 65 mmHg; PVR, 16.45 Wood units). Both patients underwent open abdominal surgery under neuraxial anesthesia without circulatory collapse with intraoperative administration of vasoconstrictors. Conclusion: Although anesthetic care must be personalized depending on the pathology and severity of PH, neuraxial anesthesia may be an option for patients with severe PH undergoing abdominal surgery. [ABSTRACT FROM AUTHOR]

This study presents a novel mechanism for the control of a wheeled robot maneuvering with a single actuator. Elements of snakeboard and two-wheeled skateboard propulsion are applied to the design. Two passive wheels, i.e., casters whose orientation can be controlled, are attached in the back and front of the robot body, and a rotor rotates above the body to induce body propulsion using its counter torque. Three degrees of freedom of motion, i.e., the orientation of the rotor and each of the two casters, are mechanically coupled to the single actuator via a torque limiter. The stoppers are set to restrict the angle of the caster orientation, and a torque limiter allows the rotor to continue rotating without being affected by the stopper's restriction to the range of motion. Experiments demonstrate that the sinusoidal rotor rotation can propel this robot forward and that adding the increasing or decreasing offset to the sinusoidal rotor rotation can curve the robot's motion. Next, a method to position the robot at a specified goal position is proposed, assuming that the current position of the robot is detectable in every control cycle. This method adjusts the rate of increase or decrease of the offset in sinusoidal rotor rotation depending on the direction of the goal position. Introducing the motion capture system enables the robot to successfully reach the specified goal positions. [ABSTRACT FROM AUTHOR]

Background: Differentiation between primary ocular adnexal mucosa-associated lymphoid tissue (POA-MALT) lymphoma and reactive lymphoid hyperplasias sometimes may be difficult. We have examined the treatment-associated mortality of POA-MALT lymphoma after confirmed diagnosis and evaluated their proper treatments. Patients and methods: From 1991 through 2016, cases of POA-MALT lymphoma were retrospectively analyzed based on their pathological and molecular/immunological diagnoses. Results: A total of 78 cases with POA-MALT lymphoma with a median age of 66 years were analyzed over median/mean observations of 6.4/7.1 years. Forty-four patients (56%) were diagnosed with IgH gene clonality and 10 patients (13%) were diagnosed with flow cytometric analysis in addition to the pathological decision. The rest (24 patients, 31%) were diagnosed employing pathological decisions of hemato-pathologists and clinical decisions. All patients, except cases of watchful waiting, achieved complete remission. After initial treatment, 68 patients (87%) presented disease-free during the observation period. As treatment, a radiotherapy-based strategy was followed with 15 patients (19%, group A). Immuno-chemotherapy was administered to 24 patients (31%, B). Surgical extraction only was selected for 36 patients (46%, C). Watchful waiting was selected with three patients (4%). Recurrence after the initial treatment was found in one patient (7%) out of A, in three patients (13%) out of B, and in six patients (17%) out of C, respectively. Progression-free survivals at 5 and 10 years were 100 and 100% in A, 95 and 75% in B, and 88 and 81% in C, respectively. The recurrence rates between the patients who were diagnosed with only pathological decision (n = 24) and the patients who were diagnosed with molecular and immunological procedures (n = 54) did not show any statistical differences. Conclusion: Our results indicate that radiotherapy-based treatment strategies for patients with POA-MALT lymphoma show a low rate of recurrence and may improve their prognosis even after the accurate diagnosis. However, contamination of the cases with reactive (polyclonal) lymphoid hyperplasia into those with MALT lymphoma should be carefully removed to avoid unnecessary treatment for malignancies that do not exist. [ABSTRACT FROM AUTHOR]

The numerical analysis of a turbulent sonic jet from a two-dimensional convergent nozzle has been carried out using the compressible k-ɛ turbulence model and TVD finite difference scheme. Numerical conditions have been varied over a range of operating pressure ratios from 1.893 to 6.0 which cover the jet flow conditions from correctly expanded to underexpanded. Numerical flow visualization of sonic jet structure using the computer schlieren, a relation between shock cell length in the jet with the operating pressure ratio and the pressure distribution along jet centerline are obtained. Also, a transition process of a two-dimensional sonic jet from correctly expanded to underexpanded conditions is shown in detail and a flow model of jet structure is proposed. [ABSTRACT FROM AUTHOR]