Hepatic encephalopathy due to extrahepatic portosystemic shunt

Clinicians should recognize extrahepatic portosystemic shunt as a cause of refractory or intermittent hepatic encephalopathy. Treatment strategies should be individualized according to patients' anatomic and hemodynamic status

Comparison of anti-scatter grids for digital imaging with use of a direct-conversion flat-panel detector

Our purpose in this study was to establish a selection standard for anti-scatter grids for a direct conversion flat-panel detector (FPD) system. As indices for grid evaluation, we calculated the selectivity, Bucky factor, and the signal-to-noise ratio improvement factor (SIF) by measuring rates of scatter transmission, primary transmission, and total transmission (based on the digitally displayed measurement values of the FPD system), using 4 acrylic phantoms of different thicknesses. The results showed that the SIF was less than 1.0 when the phantom thickness was 5 cm. When the phantom thickness was 25 cm and the grid ratio was 16:1, the SIF was 1.505 and 1.518 (maximum value) at 90 and 120 kV, respectively. Compared with the grid ratio of 12:1, the SIF at the grid ratio 16:1 was improved by 6.1% at 90 kV, and by 7.0% at 120 kV. In a direct-conversion FPD system, the grid ratio of 16:1 is considered adequate for eliminating the scattered-radiation effect when much scattered radiation is present, such as with a thick imaged object or a high X-ray tube voltage. © Japanese Society of Radiological Technology and Japan Society of Medical Physics 2011.Thesis of Mizuta, Masayoshi / 水田 正芳 博士学位論文(金沢大学 / 大学院医薬保健学総合研究科

全身麻酔時に発生した小児気管支異物の1例

京都府立医科大学附属北部医療センター　耳鼻咽喉科Department of Otolaryngology, North Medical Center, Kyoto Prefectural University of Medicine6歳、男児。扁桃肥大、睡眠時無呼吸症候群に対して、全身麻酔下にて両側口蓋扁桃摘出術施行予定であったが、麻酔導入のマスク換気時に上顎の乳歯が消失した。挿管前後、術中も発見に至らず、気管支ファイバーにて右上葉気管支B2 に陥頓する乳歯を確認。様々な器具を用いたが、最終的にバスケット鉗子にて摘出できた。その後特に合併症なく4 日後に退院した

Present developments in reaching an international consensus for a model-based approach to particle beam therapy

Particle beam therapy (PBT), including proton and carbon ion therapy, is an emerging innovative treatment for cancer patients. Due to the high cost of and limited access to treatment, meticulous selection of patients who would benefit most from PBT, when compared with standard X-ray therapy (XRT), is necessary. Due to the cost and labor involved in randomized controlled trials, the model-based approach (MBA) is used as an alternative means of establishing scientific evidence in medicine, and it can be improved continuously. Good databases and reasonable models are crucial for the reliability of this approach. The tumor control probability and normal tissue complication probability models are good illustrations of the advantages of PBT, but pre-existing NTCP models have been derived from historical patient treatments from the XRT era. This highlights the necessity of prospectively analyzing specific treatment-related toxicities in order to develop PBT-compatible models. An international consensus has been reached at the Global Institution for Collaborative Research and Education (GI-CoRE) joint symposium, concluding that a systematically developed model is required for model accuracy and performance. Six important steps that need to be observed in these considerations include patient selection, treatment planning, beam delivery, dose verification, response assessment, and data analysis. Advanced technologies in radiotherapy and computer science can be integrated to improve the efficacy of a treatment. Model validation and appropriately defined thresholds in a cost-effectiveness centered manner, together with quality assurance in the treatment planning, have to be achieved prior to clinical implementation

Model experiment of magnetic field amplification in laser-produced plasmas via the Richtmyer-Meshkov instability

A model experiment of magnetic field amplification (MFA) via the Richtmyer-Meshkov instability (RMI) in supernova remnants (SNRs) was performed using a high-power laser. In order to account for very-fast acceleration of cosmic rays observed in SNRs, it is considered that the magnetic field has to be amplified by orders of magnitude from its background level. A possible mechanism for the MFA in SNRs is stretching and mixing of the magnetic field via the RMI when shock waves pass through dense molecular clouds in interstellar media. In order to model the astrophysical phenomenon in laboratories, there are three necessary factors for the RMI to be operative: a shock wave, an external magnetic field, and density inhomogeneity. By irradiating a double-foil target with several laser beams with focal spot displacement under influence of an external magnetic field, shock waves were excited and passed through the density inhomogeneity. Radiative hydrodynamic simulations show that the RMI evolves as the density inhomogeneity is shocked, resulting in higher MFA

Effect of BNT162b2 mRNA COVID-19 vaccine on sperm morphokinetics and DNA integrity: A prospective observational study in Japan

Objective: To assess whether the coronavirus disease 2019 (COVID-19) mRNA vaccine affects sperm morphokinetics using a computer-assisted semen analyzer and other semen parameters using a sperm chromatin structure assay. Methods: Healthy male volunteers in two Japanese clinics between May 2021 and December 2021 were prospectively analyzed. Participants donated sperm twice, two days apart, in the following phases: before vaccination, 2 weeks after the first vaccine dose, and 2, 4, and 12 weeks after the second dose. Basic sperm parameters, sperm motility characteristics, and the percentage of DNA-damaged sperm were compared among the different phases. Results: Ninety-six semen samples from ten volunteers, who were vaccinated with the BNT162b2 mRNA vaccine, were evaluated. There were no significant differences between any phases in basic semen findings and parameters of the sperm chromatin structure assays. Regarding sperm motion characteristics, the average linear velocity, beat-cross frequency, and sperm motility index significantly decreased after the second vaccine dose (P=0.018, P=0.003, and P=0.027, respectively), with no significant differences between any two phases by post-hoc pairwise comparisons. Conclusions: After COVID-19 mRNA vaccination, while sperm motion characteristics might fluctuate, no apparent deterioration of basic sperm parameters or sperm DNA integrity was observed. Given the adverse effects of COVID-19 on sperm, our findings suggest that there might be no reason to refrain from vaccination for healthy individuals

Characteristics of limb kinematics in the gait disorders of post-stroke patients

Abstract Post-stroke gait disorders involve altered lower limb kinematics. Recently, the endpoint of the lower limb has been used as a control variable to understand gait kinematics better. In a cross-sectional study of sixty-seven post-stroke patients, the limb extension angle and effective limb length during gait were used as input variables with a mixed Gaussian model-based probabilistic clustering approach to identify five distinct clusters. Each cluster had unique characteristics related to motor paralysis, spasticity, balance ability, and gait strategy. Cluster 1 exhibited high limb extension angle and length values, indicating increased spasticity. Cluster 2 had moderate extension angles and high limb lengths, indicating increased spasticity and reduced balance ability. Cluster 3 had low limb extension angles and high limb length, indicating reduced balance ability, more severe motor paralysis, and increased spasticity. Cluster 4 demonstrated high extension angles and short limb lengths, with a gait strategy that prioritized stride length in the component of gait speed. Cluster 5 had moderate extension angles and short limb lengths, with a gait strategy that prioritized cadence in the component of gait speed. These findings provide valuable insights into post-stroke gait impairment and can guide the development of personalized and effective rehabilitation strategies