241 research outputs found

    Acupuncture Muscle Channel in the Subcutaneous Layer of Rat Skin

    Get PDF
    AbstractUsing a mixed-dye injection technique, we found a novel kind of muscle fiber with a lumen, established its precise location in the subcutaneous muscle layer along the acupuncture muscle of the bladder line, and determined its detailed ultrastructure. The channels with flowing liquid were a novel kind of muscle fibers with lumens and they were located in the subcutaneous muscle layer of rat. Their detection was realized by using chrome-hematoxylin and a mixture of fluorescent nanoparticles and commercial Pelikan ink. These acupuncture muscle channels were hidden among the neighboring skin skeletal muscle fibers and were barely distinguishable from them with light microscopes. Only with a transmission electron microscope were their characteristic features shown to be different from normal skin skeletal muscle. These features included undifferentiated muscle fibers that resembled immature myofibrils without Z-lines and reassembled telophase nuclei

    Real-time bladder volume monitoring by the application of a new implantable bladder volume sensor for a small animal model

    Get PDF
    AbstractAlthough real-time monitoring of bladder volume together with intravesical pressure can provide more information for understanding the functional changes of the urinary bladder, it still entails difficulties in the accurate prediction of real-time bladder volume in urodynamic studies with small animal models. We studied a new implantable bladder volume monitoring device with eight rats. During cystometry, microelectrodes prepared by the microelectromechanical systems process were placed symmetrically on both lateral walls of the bladder, and the expanded bladder volume was calculated. Immunohistological study was done after 1 week and after 4 weeks to evaluate the biocompatibility of the microelectrode. From the point that infused saline volume into the bladder was higher than 0.6mL, estimated bladder volume was statistically correlated with the volume of saline injected (p<0.01). Additionally, the microelectromechanical system microelectrodes used in this study showed reliable biocompatibility. Therefore, the device can be used to evaluate changes in bladder volume in studies with small animals, and it may help to provide more information about functional changes in the bladder in laboratory studies. Furthermore, owing to its biocompatibility, the device could be chronically implanted in conscious ambulating animals, thus allowing a novel longitudinal study to be performed for a specific purpose

    Strength of Footing with Punching Shear Preventers

    Get PDF
    The punching shear failure often governs the strength of the footing-to-column connection. The punching shear failure is an undesirable failure mode, since it results in a brittle failure of the footing. In this study, a new method to increase the strength and ductility of the footing was proposed by inserting the punching shear preventers (PSPs) into the footing. The validation and effectiveness of PSP were verified through a series of experimental studies. The nonlinear finite element analysis was then performed to demonstrate the failure mechanism of the footing with PSPs in depth and to investigate the key parameters that affect the behavior of the footing with PSPs. Finally, the design recommendations for the footing with PSPs were suggested

    Use of Magnetic Nanoparticles to Visualize Threadlike Structures Inside Lymphatic Vessels of Rats

    Get PDF
    A novel application of fluorescent magnetic nanoparticles was made to visualize a new tissue which had not been detectable by using simple stereomicroscopes. This unfamiliar threadlike structure inside the lymphatic vessels of rats was demonstrated in vivo by injecting nanoparticles into lymph nodes and applying magnetic fields on the collecting lymph vessels so that the nanoparticles were taken up by the threadlike structures. Confocal laser scanning microscope images of cryosectioned specimens exhibited that the nanoparticles were absorbed more strongly by the threadlike structure than by the lymphatic vessels. Further examination using a transmission electron microscope revealed that the nanoparticles had been captured between the reticular fibers in the extracellular matrix of the threadlike structures. The emerging technology of nanoparticles not only allows the extremely elusive threadlike structures to be visualized but also is expected to provide a magnetically controllable means to investigate their physiological functions

    Pneumatization Pattern of the Frontal Recess: Relationship of the Anterior-to-Posterior Length of Frontal Isthmus and/or Frontal Recess with the Volume of Agger Nasi Cell

    Get PDF
    ObjectivesWe analyzed the pneumatization pattern of the frontal recess (FR) in a Korean population. We also determined the correlation between the volume of the agger nasi cell (ANC) and the anterior-to-posterior (A-P) length of the frontal isthmus (FI) and FR.MethodsMultiplanar paranasal sinus computed tomography (CT) images from 105 patients who underwent endoscopic sinus surgery were reviewed. The prevalence of frontal recess cells (FRCs), thickness of the frontal beak (FB), volume of the ANC, A-P length of the FI, and FR were evaluated.ResultsThe ANC was identified in 96% of the patients and frontal cells (FCs) in 32% (FC type 1, 24.2%; type 2, 4.2%; type 3, 3.1%; and type 4, 0%). The prevalences of frontal bullar, suprabullar, supraorbital ethmoidal, and interfrontal sinus septal cells were 10%, 7.8%, 3.6%, and 6.8%, respectively. The A-P lengths of the FR and FI were 10.1±3.1 and 8.4±2.9 mm, respectively. The thickness of the FB was 7.8±1.8 mm and the volume of the ANC averaged 394.1±240.5 mm3. The thickness of the FB did not correlate with the volume of the ANC. In contrast, the A-P length of the FI and FR were positively correlated with the volume of the ANC.ConclusionANCs and FCs were found in 96% and 32% of the cases in this series. FC type 4 was not seen. What appeared to be FC4 on conventional CT was identified as FBC from reconstructed parasagittal images. A large ANC increased the A-P length of the FI and FR, regardless of the thickness of the FB

    Prognosis according to the timing of percutaneous coronary intervention in non-ST segment elevation myocardial infarction, based on the Korean Acute Myocardial Infarction Registry (KAMIR)

    Get PDF
    Background: Patients with acute coronary syndrome without ST-segment elevation (ACS- -NSTE) are at risk for adverse cardiac events. Based on data in the Korean Acute Myocardial Infarction Registry (KAMIR), we analyzed the prognosis according to the timing of percutaneous coronary intervention (PCI) in patients with NSTEMI in Korea. Methods and results: 2,455 patients with NSTEMI in KAMIR were classified according to the time interval from the onset of cardiac symptoms to PCI. Patients in Group I underwent PCI within 24 hours of the onset of symptoms; in Group II between 24 and 48 hours; and in Group III after 48 hours. Major adverse cardiac events (MACEs) are defined as cardiac death, non-cardiac death, myocardial infarction, revascularization and coronary-artery bypass graft surgery. The MACEs were compared between groups. Of the 2,455 patients, 743 (30.2%) were assigned to Group I, 583 (23.7%) to Group II, and 1,129 (45.9%) to Group III. The total incidence of MACEs was higher in Group I than Group III, and similar between Groups I and II (Group I: 15.1%, Group II: 14.4%, Group III: 11.6%, p = 0.053). The incidence of MACEs in the intermediate TIMI risk score group had decreased as the intervention time was delayed. Conclusions: The prognosis according to the timing of PCI in patients with NSTEMI was similar based on the data in KAMIR. TIMI risk score was related to a high incidence of MACEs. (Cardiol J 2011; 18, 4: 421&#8211;429

    The Modified Chimney Technique With a Thoracic Aortic Stent Graft to Preserve the Blood Flow of the Left Common Carotid Artery for Treating Descending Thoracic Aortic Aneurysm and Dissection

    Get PDF
    While thoracic endovascular aortic repair is an effective treatment option for descending thoracic aorta pathology, it does have limitations. The main limitation is related to the anatomical difficulties when disease involves the aortic arch. A fenestrated, branched aortic stent graft and hybrid operation has been introduced to overcome this limitation, but it is a custom-made device and is time consuming to manufacture. Furthermore, these devices cannot be used in an emergency setting. We report two patients with massive descending thoracic aortic aneurysm and ruptured aortic dissection very near the aortic arch who underwent a procedure which we named the modified chimney technique. The modified chimney technique can be used as a treatment option in such an emergency situation or as a rescue procedure when aortic pathology is involved near the supra-aortic vessels
    corecore