1.Development of a new alternative method to inhalation exposure: intratracheal instillation studies using molecular dispersion.
Toshiki MORIMOTO ; Chinatsu NISHIDA ; Hiroto IZUMI ; Taisuke TOMONAGA ; Kazuma SATO ; Yasuyuki HIGASHI ; Ke-Yong WANG ; Takuma KOJIMA ; Kazuo SAKURAI ; Akihiro MORIYAMA ; Jun-Ichi TAKESHITA ; Kei YAMASAKI ; Hidenori HIGASHI ; Kazuhiro YATERA ; Yasuo MORIMOTO
Environmental Health and Preventive Medicine 2025;30():69-69
BACKGROUND:
Organic chemicals have been known to cause allergic diseases such as bronchial asthma and hypersensitivity pneumonitis; however, the possibility that they do not cause irreversible pulmonary fibrosis has not been considered. Polyacrylic acid (PAA), an organic chemical, has caused irreversible progressive pulmonary fibrosis in exposed workers, indicating its potential to induce pulmonary inflammation and fibrosis. Although intratracheal instillation studies are commonly used for evaluating lung pathology, traditional methods face challenges with chemical substances, particularly nanoparticles, which tend to aggregate in suspension and prevent uniform pulmonary distribution. Such aggregation alters the qualitative and quantitative responses to lung injury, limiting accurate assessment of lung pathology. To overcome this limitation, we developed a 'molecular dispersion method' that uses pH modification to negative charges to PAA particles, maintaining their dispersion. Using this method, we investigated the effects of PAA on pulmonary inflammation and fibrosis in a rat model.
METHODS:
F344 rats were intratracheally instilled with PAA using molecular dispersion (0.1 mg/rat, 1.0 mg/rat), PAA without molecular dispersion (1.0 mg/rat), and normal saline (control group). Rats were sacrificed at 3 days, 1 week, 1 month, 3 months, and 6 months after exposure to examine inflammatory and fibrotic responses.
RESULTS:
PAA caused persistent increases in neutrophil influx in the bronchoalveolar lavage fluid (BALF) from 3 days to 1 month following instillation. In histopathological findings, the group with molecular dispersion had almost no inflammatory masses in the lung tissue compared to the group without molecular dispersion, and exhibited relatively uniform dispersion.
CONCLUSION
Intratracheal instillation of dispersed PAA induced neutrophil inflammation and fibrosis in the rat lung, suggesting that PAA might have pulmonary inflammogenicity and fibrogenicity. Intrapulmonary dispersion of PAA particles following intratracheal instillation studies using the molecular dispersion method was similar to that following inhalation studies.
Animals
;
Rats, Inbred F344
;
Acrylic Resins/adverse effects*
;
Rats
;
Inhalation Exposure/adverse effects*
;
Male
;
Pulmonary Fibrosis/pathology*
;
Pneumonia/pathology*
;
Lung/pathology*
;
Bronchoalveolar Lavage Fluid/cytology*
2.Total Arch Replacement for Aortic Arch Thrombosis Combined with Severe Mitral Regurgitation
Masato SAITOH ; Takuma YAMASAKI ; Tomoaki TANABE ; Shuichi TOCHIGI ; Shoh TATEBE ; Imun TEI
Japanese Journal of Cardiovascular Surgery 2024;53(3):131-135
A 74-year-old male with exertional breathlessness was referred to our hospital by his general physician. Echocardiography revealed severe mitral regurgitation. An aortic and coronary computed tomography scan revealed aortic arch thrombosis and coronary artery stenosis in the left anterior descending (LAD) artery. In consideration of the risk of embolization, the patient underwent emergency surgery on the same day. The surgical procedure involved the replacement of the aortic arch with a fenestrated frozen elephant trunk, mitral valvuloplasty, and coronary artery bypass graft for the LAD artery. Blood tests revealed no underlying coagulopathy. The patient did not develop any postoperative complications. He was discharged home on his own on postoperative day 19. One year after the surgery, no recurrence of thrombosis or heart failure was observed. Severe mitral regurgitation complicated with intraaortic thrombosis is rare. This case report indicates that intraaortic thrombosis can occur even in patients without any underlying blood coagulation abnormalities. We report this case with a review of the literature.
3.Role of the Nurse Practitioner (NP) in Cardiovascular Surgery
Masato SAITOH ; Takuma YAMASAKI ; Tomoaki TANABE ; Shuichi TOCHIGI ; Shoh TATEBE ; Yuki ICHIMORI ; Imun TEI
Japanese Journal of Cardiovascular Surgery 2022;51(6):339-344
Background: Despite the recent increase in the number of institutions introducing nurse practitioners to perioperative management following cardiovascular surgery, limited reports have evaluated their performance. Objective: The current study aimed to evaluate nurse practitioners' intervention based on perioperative outcomes following cardiovascular surgery. Methods: We performed a retrospective visualization of perioperative data following open-heart surgeries conducted at our hospital from April 1, 2019 to May 31, 2021, with the NP (99 patients) and DR (109 patients) groups consisting of patients whose first assistant was a nurse practitioner and physician, respectively. Results: No significant differences in patient characteristics were observed between the two groups. There were no significant differences in the operative time (304.4±92.7 vs. 301.4±86.8: min; p=0.947), death within 30 days (n)(2 vs. 2; p=0.923), and ICU stay (5.72±4.42 vs. 6.65±5.43: days; p=0.302), between the two groups. No significant difference was observed in the occurrence of postoperative complications between the two groups. The NP group had significantly shorter hospital stay (18.6±6.7 vs. 23.0±9.8: days; p<0.001) and duration of ventilator management (19.7±22.6 vs. 28.8±50.2: h; p=0.047) than the DR group. Discussion: The NP and DR groups exhibited comparable surgical outcomes. Perioperative management by a team including nurse practitioners, rather than by physicians alone, has been considered to reduce the duration of time spent on ventilator management and enable earlier hospital discharge, resulting in shorter hospital stays. This suggests that nurse practitioners, including surgical assistants under the direct supervision of physicians, may be able to safely perform perioperative management.
4.The Effect of Simultaneous Antigravity Treadmill Training and Electrical Muscle Stimulation After Total Hip Arthroplasty: Short Follow-Up Time
Yukio MIKAMI ; Naoya ORITA ; Takuma YAMASAKI ; Yoshiichiro KAMIJO ; Hiroaki KIMURA ; Nobuo ADACHI
Annals of Rehabilitation Medicine 2019;43(4):474-482
OBJECTIVE: To assess the effectiveness of our devised hybrid physiotherapy regime using an anti-gravity treadmill and a low-frequency electrical stimulation device, as measured in patients with hip osteoarthritis after total hip arthroplasty (THA). METHODS: The outcomes of the postoperative rehabilitation in 44 patients who underwent THA for hip osteoarthritis were retrospectively examined. The conventional group (n=22) underwent the postoperative rehabilitation according to our protocol, while the hybrid group (n=22) underwent the same training, along with training on an anti-gravity treadmill and training using a low-frequency therapeutic device. The outcome measures were recorded and reviewed with the Numerical Rating Scale for pain, which rates pain on an 11-point scale from 0 to 10, surgical side knee joint extension force, 10-m walking test, Timed Up and Go test, and the 6-minute walking distance (6MD). The outcome measurement was taken 2 weeks after conducting pre-operation and antigravity treadmill training and electrical muscle stimulation, and compared the respective results. RESULTS: At the timeframe of 2 weeks from the surgery after conducting a devised hybrid physiotherapy, the values of knee extension muscle strength and 6MD were not worse in the hybrid group than conventional group. In the evaluation at 2 weeks after surgery, the knee extension muscle strength and 6MD values significantly decreased compared with the preoperative values only in the conventional group. CONCLUSION: Lower limb muscular strength and endurance were maintained in the hybrid group, which suggested that hybrid physiotherapy could maintain physical functions early after THA operation.
Arthroplasty, Replacement, Hip
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Electric Stimulation
;
Follow-Up Studies
;
Humans
;
Knee
;
Knee Joint
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Lower Extremity
;
Muscle Strength
;
Osteoarthritis, Hip
;
Outcome Assessment (Health Care)
;
Rehabilitation
;
Retrospective Studies
;
Walking
5.A Case of Total Arch Replacement for Non-anastomotic Pseudoaneurysm by Proximal Stent Graft Induced-Vascular Graft Perforation in Loeys-Dietz Syndrome after Total Aortic Replacement
Yu HOHRI ; Takuma YAMASAKI ; Yuichi MATSUZAKI ; Takeshi HIRAMATSU
Japanese Journal of Cardiovascular Surgery 2018;47(2):82-87
A 26-year-old lady with Loeys Dietz syndrome had undergone 5 consecutive operations from 2007 to 2014. Finally, her total aorta was replaced by vascular grafts and stent grafts. The patient was admitted to our hospital with headache and dizziness in 2016. Computed tomography showed a giant pseudoaneurysm at the aortic arch with extravasation from the vascular graft. The proximal flares of thoracic stent grafts caused perforation of thoracic vascular grafts. Cerebral perfusion was not sufficient, because this aneurysm compressed the innominate, left carotid and left subclavian arteries. Decreasing of cerebral perfusion caused headache and dizziness. We performed total arch replacement. We started extracorporeal circulation before median sternotomy but the aneurysm ruptured during median sternotomy. We controlled the bleeding by manual compression and immediately started selective cerebral perfusion and induced cardiac arrest. After opening the distal portion, we cut down the proximal flares of thoracic stent graft and inserted an elephant trunk into the stent graft. We sutured between the new vascular graft and the stent graft and covered the suture line with another short vascular graft. As a result we could protect the vascular graft from the stent graft. Computed tomography demonstrated that the pseudoaneurysm and extravasation disappeared. Cerebral perfusion increased and the patient's symptoms improved. Postoperatively the patient was discharged from our hospital without any major complications at POD 11.
6.Rotational Acetabular Osteotomy.
Yuji YASUNAGA ; Jiro FUJII ; Ryuji TANAKA ; Shinji YASUHARA ; Takuma YAMASAKI ; Nobuo ADACHI ; Mitsuo OCHI
Clinics in Orthopedic Surgery 2017;9(2):129-135
Hip dysplasia is the most common cause of secondary osteoarthritis (OA). To prevent the early onset of secondary OA, Nishio's transposition osteotomy, Steel's triple osteotomy, Eppright's dial osteotomy, Wagner's spherical acetabular osteotomy, Tagawa's rotational acetabular osteotomy (RAO), and Ganz' periacetabular osteotomy (PAO) have been proposed. PAO and RAO are now commonly used in surgical treatment of symptomatic acetabular dysplasia in Europe, North America, and Asia. The aim of this paper is to present the followings: the patient selection criteria for RAO; the surgical technique of RAO; the long-term outcome of RAO; and the future perspectives.
Acetabulum*
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Asia
;
Europe
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Hip Dislocation
;
North America
;
Osteoarthritis
;
Osteotomy*
;
Patient Selection
7.An Acute Type A Aortic Dissection Complicated with Malperfusion of the Left Main Coronary Artery
Takuma Yamasaki ; Eisei Koh ; Yuji Kaku ; Shuhei Fujita ; Junko Katagiri
Japanese Journal of Cardiovascular Surgery 2016;45(2):89-93
A 64-year-old woman was admitted to our hospital with sudden chest and back pain. Computed tomography showed acute type A aortic dissection complicated with malperfusion of the left main coronary artery (LMT). Immediately after the CT, the patient went into sudden shock. Electrocardiogram showed ventricular tachycardia and ventricular fibrillation. Percutaneous cardio-pulmonary support was administered and coronary arteriogram (CAG) was performed. CAG revealed LMT stenosis and intravascular ultrasound showed mobile intimal flap at the LMT. Percutaneous coronary intervention of the LMT was performed. The patient recovered from shock and was treated with ascending aorta replacement with CABG. The patient was discharged from the hospital without any major complication.
8.A Case of Primary Cardiac Lymphoma with Rapid Growth
Hidetake Kawajiri ; Eisei Koh ; Noriyasu Masuda ; Takuma Yamasaki
Japanese Journal of Cardiovascular Surgery 2013;42(4):312-315
A 76-year-old woman, suffering from rapidly worsening dyspnea, and general fatigue was referred for evaluation and treatment of cardiac tumor. Echocardiography and computed tomography revealed a large tumor occupying the right atrium and inferior vena cava. We performed partial resection with cardiopulmonary bypass, in order to improve hemodynamics. The pathological examination suggested malignant lymphoma, diffuse large B-cell type. The patient was treated with cyclophosphamide, cyosine, arabinoside, etoposide, dexamethasone and rituximab (CHASER) postoperatively and gained complete response.


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