27 research outputs found
Design of Picosecond Modelocked Nd : YAG Laser
Infrared picosecond puIse trains(~7 ns pulse separation) have been obtained from a passive modelocked Nd : YAG laser, Modelocking is achieved by a saturable absorber dye(NDL l12)in 1,2-dichloroethane. The pulse duration is measured by TPF technique to be~30 ps. The efficiency with which energy is transfered from a lamp to the Nd : YAG rod is determined by the delay time of emission from a krypton flashlamp. By varying the impedance characteristics of the krypton flashlamp, the optimum delay time (~105 μs) is obtained. In order to generate the stable picosecond pulse ( ~3 percent fluctuation), the output voltage fluctuation of Power supply must be held within ~2 percent. The SHG (532 nm) and the THG (355 nm) of picosecond pulses from the Nd : YAG laser were also obtained by using KDP(KH₂ P0₄)crystals of Type I and Type II Phase-matching, respectively
Syncope and loss of consciousness after implantation of a cardioverter-defibrillator in patients with Brugada syndrome: Prevalence and characteristics in long-term follow-up
Background Syncope is a significant prognostic factor in patients with Brugada syndrome (BrS). However, the risk of ventricular arrhythmia in patients with nonarrhythmic loss of consciousness (LOC) is similar to that in asymptomatic patients. LOC events after implantable cardioverter-defibrillator (ICD) implantation may provide insights into underlying causes of the initial LOC episode.
Objective The purpose of this study was to examine LOC characteristics following ICD implantation.
Methods We retrospectively analyzed 112 patients with BrS (mean age 47 years; 111 men) who were treated with an ICD. The patients were classified into 3 groups based on symptoms at implantation: asymptomatic (35 patients); LOC (46 patients); and ventricular tachyarrhythmia (VTA) (31 patients). We evaluated the incidence and cause of LOC during long-term follow-up after ICD implantation.
Results During mean follow-up of 12.2 years, 41 patients (37%) experienced LOC after ICD implantation. Arrhythmic LOC occurred in 5 asymptomatic patients, 14 LOC patients, and 16 patients with VTA. Nonarrhythmic LOC, similar to the initial episode, occurred after ICD implantation in 6 patients with prior LOC (2 with neurally mediated syncope and 4 with epilepsy). Most epileptic patients experienced LOC during rest or sleeping, and did not show an abnormal encephalogram during initial evaluation of the LOC episodes.
Conclusion After ICD implantation, 13% of patients had nonarrhythmic LOC similar to the initial episode. Accurate classification of LOC based on a detailed medical history is important for risk stratification, although distinguishing arrhythmic LOC from epilepsy-related LOC episodes can be challenging depending on the circumstances and characteristics of the LOC event
Significant Delayed Activation on the Right Ventricular Outflow Tract Represents Complete Right Bundle-Branch Block Pattern in Brugada Syndrome
Background: The appearance of complete right bundle-branch block (CRBBB) in Brugada syndrome (BrS) is associated with an increased risk of ventricular fibrillation. The pathophysiological mechanism of CRBBB in patients with BrS has not been well established. We aimed to clarify the significance of a conduction delay zone associated with arrhythmias on CRBBB using body surface mapping in patients with BrS.
Methods and Results: Body surface mapping was recorded in 11 patients with BrS and 8 control patients both with CRBBB. CRBBB in control patients was transiently exhibited by unintentional catheter manipulation (proximal RBBB). Ventricular activation time maps were constructed for both of the groups. We divided the anterior chest into 4 areas (inferolateral right ventricle [RV], RV outflow tract [RVOT], intraventricular septum, and left ventricle) and compared activation patterns between the 2 groups. Excitation propagated to the RV from the left ventricle through the intraventricular septum with activation delay in the entire RV in the control group (proximal RBBB pattern). In 7 patients with BrS, excitation propagated from the inferolateral RV to the RVOT with significant regional activation delay. The remaining 4 patients with BrS showed a proximal RBBB pattern with the RVOT activation delay. The ventricular activation time in the inferolateral RV was significantly shorter in patients with BrS without a proximal RBBB pattern than in control patients.
Conclusions: The CRBBB morphology in patients with BrS consisted of 2 mechanisms: (1) significantly delayed conduction in the RVOT and (2) proximal RBBB with RVOT conduction delay. Significant RVOT conduction delay without proximal RBBB resulted in CRBBB morphology in patients with BrS
Combination chemotherapy of advanced non-Hodgkin's lymphoma with adriamycin, vincristine, ifosfamide and prednisolone (AVIP): a preliminary report
Eighteen patients with advanced non-Hodgkin's lymphoma other than the diffuse histiocytic type were treated with a combination of adriamycin, vincristine, ifosfamide and prednisolone (AVIP). The objective response rate was 83% (15/18); 61% (11/18) achieved complete remission. The median duration of complete remission was 11 months ranging from 2 to 39+ months. Eleven of the 18 patients are still alive during the median follow-up time of 13 months. The median survival was 14+ months for complete responders, and 9.5 months for partial and nonresponders. A myelosuppressive toxicity was well tolerated. AVIP offers some hope as treatment of advanced non-Hodgkin's lymphoma.</p
Phase II study of ifosfamide, cisplatin, and vindesine combination in advanced non-small cell lung cancer.
Twenty-seven previously untreated patients with unresectable non-small cell lung cancer were treated with a 3-drug combination of ifosfamide, cisplatin, and vindesine as a phase II study. Patients received ifosfamide, 1.3g/m2, on days 1 to 5; cisplatin, 20mg/m2, on days 1 to 5; and vindesine, 3mg/m2, on days 1 and 8; with a sufficient parenteral hydration. Courses were repeated every 4 weeks. Twenty males and seven females with a median age of 61 years were treated and fully evaluated. Five patients had stage IIIA, seven had stage IIIB, and 15 had stage IV disease. One patient with adenocarcinoma achieved a complete response and 16 achieved a partial response, for an overall response rate of 63% (95% confidence limit: 45% to 81%). The median duration of response was 34 weeks (range: 9 to 52 weeks). The median survival time was 58 weeks for patients with IIIA/B disease, and 33 weeks for those with IV disease. The major toxicity was myelosuppression, however, it was generally well-tolerated. These results indicate that the 3-drug combination is active against non-small cell lung cancer and warrants further clinical trials.</p
Survey of Period Variations of Superhumps in SU UMa-Type Dwarf Novae
We systematically surveyed period variations of superhumps in SU UMa-type
dwarf novae based on newly obtained data and past publications. In many
systems, the evolution of superhump period are found to be composed of three
distinct stages: early evolutionary stage with a longer superhump period,
middle stage with systematically varying periods, final stage with a shorter,
stable superhump period. During the middle stage, many systems with superhump
periods less than 0.08 d show positive period derivatives. Contrary to the
earlier claim, we found no clear evidence for variation of period derivatives
between superoutburst of the same object. We present an interpretation that the
lengthening of the superhump period is a result of outward propagation of the
eccentricity wave and is limited by the radius near the tidal truncation. We
interpret that late stage superhumps are rejuvenized excitation of 3:1
resonance when the superhumps in the outer disk is effectively quenched. Many
of WZ Sge-type dwarf novae showed long-enduring superhumps during the
post-superoutburst stage having periods longer than those during the main
superoutburst. The period derivatives in WZ Sge-type dwarf novae are found to
be strongly correlated with the fractional superhump excess, or consequently,
mass ratio. WZ Sge-type dwarf novae with a long-lasting rebrightening or with
multiple rebrightenings tend to have smaller period derivatives and are
excellent candidate for the systems around or after the period minimum of
evolution of cataclysmic variables (abridged).Comment: 239 pages, 225 figures, PASJ accepte
Adult-Onset Neuronal Ceroid Lipofuscinosis in a Shikoku Inu
A two-year-and-eleven-month-old male Shikoku Inu was referred for evaluation of progressive gait abnormality that had begun three months prior. Neurological examination revealed ventral flexion of the neck, a wide-based stance in the hindlimb, wide excursions of the head from side to side, tremor in all four limbs, hypermetria in all four limbs, proprioceptive deficits in all four limbs, reduced patellar reflex in both hindlimbs, and postural vertical nystagmus. Later, behavioral and cognitive dysfunction, ataxia, and visual deficits slowly progressed. Magnetic resonance imaging revealed symmetrical progressive atrophy of the whole brain and cervical spinal cord. Bilateral retinal degeneration was observed, and both flush and flicker electroretinograms were bilaterally non-recordable at the age of five years and eight months, and the dog was euthanized. Histopathologically, faint-to-moderate deposition of light-brown pigments was frequently observed in the cytoplasm of neurons throughout the cerebrum, cerebellum, and nuclei of the brainstem. The pigments were positive for Luxol fast blue, periodic acid–Schiff, and Sudan black B, and exhibited autofluorescence. Electron microscopic examination revealed the accumulation of membranous material deposition in the neuronal cytoplasm. Small foci of pigment-containing macrophages were frequently observed around the capillary vessels. Based on these clinical and pathological findings, the animal was diagnosed with adult-onset neuronal ceroid lipofuscinosis