81 research outputs found
Hydrated Seal Lip for Live Center in Machine Tools
When performing a cutting operation, a water-soluble cutting fluid may be used for cooling. Labyrinth and oil seals are commonly used in the rotating centers of machine tools to prevent the cutting fluid and dust from entering the inner parts. However, these seals do not demonstrate adequate functionality in a water-based environment. Therefore, a new rotary shaft seal was devised to separate the water-soluble cutting fluid from interacting with air. The rotary shaft seal was made from polyvinyl formal (PVF). Because PVF is a hydrophilic material, it is expected to provide suitable functionality as a seal in a water-based environment. Performance evaluations of PVF and oil seals were experimentally obtained and compared from the point of view of frictional torque, water-soluble cutting fluid leakage volume, and service life as a seal
Characterization of Swallowing Sound : Preliminary Investigation of Normal Subjects
Objective
The purpose of this study was to characterize the swallowing sound and identify the process of sound generation during swallowing in young healthy adults.
Methods
Thirty-three healthy volunteers were enrolled and allocated into three experimental groups. In experiment 1, a microphone was attached to one of eight cervical sites in 20 subjects, participants swallowed 5 ml water, and the sound waveform was recorded. In experiment 2, 10 subjects swallowed either 0, 5, 10, or 15 ml water during audio recording. In addition, participants consumed the 5 ml bolus in two different cervical postures. In experiment 3, the sound waveform and videofluoroscopy were simultaneously recorded while the three participants consumed 5 ml iopamidol solution. The duration and peak intensity ratio of the waveform were analyzed in all experimental groups.
Results
The acoustic analysis of the waveforms and videofluoroscopy suggested that the swallowing sound could be divided into three periods, each associated with a stage of the swallowing movement: the oral phase comprising posterior tongue and hyoid bone movement; the pharyngeal phase comprising larynx movement, hyoid bone elevation, epiglottis closure, and passage of the bolus through the esophagus orifice; and the repositioning phase comprising the return of the hyoid bone and larynx to their resting positions, and reopening of the epiglottis.
Conclusion
Acoustic analysis of swallowing sounds and videofluoroscopy suggests that the swallowing sound could be divided into three periods associated with each process of the swallowing movement: the oral phase comprising the posterior movement of the tongue and hyoid bone; the pharyngeal phase comprising the laryngeal movement, hyoid bone elevation, epiglottis closure, and the bolus passage to the esophagus orifice; and the repositioning phase comprising the repositioning of the hyoid bone and larynx, and reopening of the epiglottis
超音波検査を用いた嚥下音産生機序の解明
Background: Cervical auscultation is a technique frequently used for the screening of dysphagia. However, this method is difficult to evaluate objectively and it is unclear how sound is generated during the swallowing process. The aim of this study was to analyze the waveform of swallowing sound and clarify the sound production process using recordings of swallowing sounds and ultrasound images (USI), performed simultaneously.
Materials and Methods: Commercial natural spring water and natural carbonated water were used in experiments 1 and 2, respectively. In experiment 1, a microphone was attached to the skin of the neck of 20 young participants and swallowing sounds were recorded and analyzed. In experiment 2, swallowing processes in three participants were recorded by a medical ultrasonography apparatus. The ultrasonic probe was placed on the skin over one of the thyroid cartilages or the thyroid gland.
Results: The swallowing sound wave (SSW) was divided into three sectional periods. The mean duration of the first, second, and third SSW was 210 ± 147 ms, 458 ± 113 ms, and 91 ± 61 ms, respectively. The mean intensity ratio of the first, second, and third SSW was 7.8 ± 5.2, 29.2 ± 16.5, and 5.8 ± 5.1, respectively. When the ultrasonic probe was placed on the skin over one of the thyroid cartilages, in the phase between the production of the second SSW and the silent period, the USI revealed an accumulation of swallowed material around the valleculae and oropharynx. In the silent period of the second SSW, the swallowed material accumulated around the hypopharynx. When the ultrasonic probe was placed on the skin over the thyroid gland, in the silent period of the second SSW, the USI revealed that the swallowed material had passed through esophagus.
Conclusion: Waveform and USI findings from this study suggest that swallowing sound can be divided into three sectional periods: an oral phase, a pharyngeal phase, and a repositioning phase
Anesthetic Care of a Patient with AFE
Two types of amniotic fluid embolism (AFE) have been described : cardiopulmonary collapse type and disseminated intravascular coagulation (DIC) type, with the latter proposed as uterine type. This report describes a healthy 28-year-old woman who developed AFE during a cesarean section. Because of a previous cesarean section, the patient underwent an elective cesarean section, under combined spinal-epidural anesthesia, at 38 weeks of pregnancy. She began coughing 5 minutes after delivery of the fetus, subsequently becoming unconscious and developing glossoptosis and bradycardia. Her blood pressure decreased to 76/43 mmHg, and AFE was suspected. Her uterus was atonic, and she experienced persistent noncoagulant bleeding, with a final blood loss of 6300 ml. Considerable blood transfusion was required. The patient survived, and she and her baby were discharged without any sequelae on the eighth postoperative day. This patient met the Japanese criteria for clinical AFE, with an obstetrical DIC score of 21 meeting the criteria for obstetrical DIC. Early diagnosis and treatment likely resulted in patient survival
Haploinsufficiency of SAMD9L, an Endosome Fusion Facilitator, Causes Myeloid Malignancies in Mice Mimicking Human Diseases with Monosomy 7
SummaryMonosomy 7 and interstitial deletion of 7q (−7/7q−) are well-recognized nonrandom chromosomal abnormalities frequently found among patients with myelodysplastic syndromes (MDSs) and myeloid leukemias. We previously identified candidate myeloid tumor suppressor genes (SAMD9, SAMD9-like = SAMD9L, and Miki) in the 7q21.3 subband. We established SAMD9L-deficient mice and found that SAMD9L+/− mice as well as SAMD9L−/− mice develop myeloid diseases resembling human diseases associated with −7/7q−. SAMD9L-deficient hematopoietic stem cells showed enhanced colony formation potential and in vivo reconstitution ability. SAMD9L localizes in early endosomes. SAMD9L-deficient cells showed delays in homotypic endosome fusion, resulting in persistence of ligand-bound cytokine receptors. These findings suggest that haploinsufficiency of SAMD9L and/or SAMD9 gene(s) contributes to myeloid transformation
Asymptomatic coronary heart disease in patients with type 2 diabetes with vascular complications: a cross-sectional study
The effect of midazolam administration for the prevention of emergence agitation in pediatric patients with extreme fear and non-cooperation undergoing dental treatment under sevoflurane anesthesia, a double-blind, randomized study
Background: Sevoflurane is generally the preferred anesthetic agent for general anesthesia in pediatric patients, due to its rapid induction and recovery characteristics. However, it has been recognized that a major complication is emergence agitation when awakening from general anesthesia. The aim of this study was to evaluate the occurrence rate of emergence agitation in the operating room and postoperative recovery area following intraoperative administration of midazolam to pediatric patients under general anesthesia. Patients and methods: One hundred and twenty pediatric patients undergoing dental treatment under sevoflurane anesthesia were enrolled in this study. The patients were divided into three groups (n=40 each in the 0.1 mg/kg midazolam, 0.05 mg/kg midazolam, and control with saline groups). Midazolam or saline was injected intravenously approximately 30 minutes before the end of the dental treatment. We used the Richmond Agitation and Sedation Scale (RASS) to assess the level of sedation and drowsiness at emergence phase in the operating room. We also used the Pediatric Anesthesia Emergence Delirium Scale (PAED) to assess the level of agitation and delirium at the full recovery phase from anesthesia in the recovery area. Results:At the emergence phase, the incidence of emergence agitation in the 0.1 mg/kg midazolam group was significantly lower than in the other groups (p=0.0010). At the recovery phase, there was no significant difference among the three groups. The odds ratio between PAED score and RASS score was 4.0 using logistic regression analysis. The odds ratio between PAED score and Disability was 2.5. Conclusion: Administration of a single dose of 0.1 mg/kg midazolam dose significantly decreases the incidence of severe emergence agitation at the emergence after sevoflurane anesthesia, but not at the recovery phase. Furthermore, the evaluation of sedative and agitation condition using RASS score at emergence from anesthesia is useful to predict occurrence of agitation in the recovery phase
Mice with Calr mutations homologous to human CALR mutations only exhibit mild thrombocytosis
Shide, K., Kameda, T., Kamiunten, A. et al. Mice with Calr mutations homologous to human CALR mutations only exhibit mild thrombocytosis. Blood Cancer J. 9, 42 (2019). https://doi.org/10.1038/s41408-019-0202-
DOCK2 is involved in the host genetics and biology of severe COVID-19
「コロナ制圧タスクフォース」COVID-19疾患感受性遺伝子DOCK2の重症化機序を解明 --アジア最大のバイオレポジトリーでCOVID-19の治療標的を発見--. 京都大学プレスリリース. 2022-08-10.Identifying the host genetic factors underlying severe COVID-19 is an emerging challenge. Here we conducted a genome-wide association study (GWAS) involving 2, 393 cases of COVID-19 in a cohort of Japanese individuals collected during the initial waves of the pandemic, with 3, 289 unaffected controls. We identified a variant on chromosome 5 at 5q35 (rs60200309-A), close to the dedicator of cytokinesis 2 gene (DOCK2), which was associated with severe COVID-19 in patients less than 65 years of age. This risk allele was prevalent in East Asian individuals but rare in Europeans, highlighting the value of genome-wide association studies in non-European populations. RNA-sequencing analysis of 473 bulk peripheral blood samples identified decreased expression of DOCK2 associated with the risk allele in these younger patients. DOCK2 expression was suppressed in patients with severe cases of COVID-19. Single-cell RNA-sequencing analysis (n = 61 individuals) identified cell-type-specific downregulation of DOCK2 and a COVID-19-specific decreasing effect of the risk allele on DOCK2 expression in non-classical monocytes. Immunohistochemistry of lung specimens from patients with severe COVID-19 pneumonia showed suppressed DOCK2 expression. Moreover, inhibition of DOCK2 function with CPYPP increased the severity of pneumonia in a Syrian hamster model of SARS-CoV-2 infection, characterized by weight loss, lung oedema, enhanced viral loads, impaired macrophage recruitment and dysregulated type I interferon responses. We conclude that DOCK2 has an important role in the host immune response to SARS-CoV-2 infection and the development of severe COVID-19, and could be further explored as a potential biomarker and/or therapeutic target
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