Astaxanthin (AX) is a red carotenoid widely distributed in nature and possesses excellent antioxidant activity by quenching singlet oxygen and inhibiting lipid peroxidation. Recently, numerous biological activities of AX are reported. AX has been used for health supplements and cosmetics and is receiving increasing attention for complementary and alternative medicine. In this paper, we would like to clarify aspects of AX by presenting the origin, chemical properties, comparison with other carotenoids. Furthermore, we report the results of in vitro, in vivo analysis and clinical studies related to anti-lipid peroxidation, anti-inflammatory effects, blood flow improvement, effects on metabolic syndrome, anti-eye fatigue, effects on Helicobacter pylori, improved lipid metabolism, muscle endurance, effects on skin health, male infertility, pharmacokinetics, and safety.

A long-term safety study was conducted with astaxanthin derived from Haematococcus pluvialis algae extract. Fifteen healthy volunteers took 9 mg of astaxanthin daily for 12 weeks. Physiological (including doctor’s consultation), haematological, biochemical, and urinary markers were examined at weeks 0, 4, 8 and 12. No adverse effects or clinical changes were observed throughout the test period. It was concluded that a healthy adult can consume 9 mg of astaxanthin derived from Haematococcus pluvialis algae extract for 12 weeks without any safety concern.

A lower abdominal tumor with thrill and bruit was pointed out in a 59-year-old female. Angiography showed a pelvic arteriovenous malformation (AVM) with remarkably dilated vessels resembling an aneurysm. Feeding arteries for this AVM originated from the right internal iliac artery, right lumbar artery and right renal artery, and drainage blood flowed into the inferior vena cava from the dilated vessel via a large vein. At operation the right internal iliac artery and right lumbar artery were ligated and the dilated vessel with AVM, which connected with the right renal artery, was resected. An angiography 16 days after the operation revealed the normal arteries without AVM and the right internaal iliac artery filled through collateral arteries. Recently catheter embolization in frequently the first choice for treatment of AVM. However, in the case of AVM with aneurysmal dilated vessels, surgical resection should be selected.

Astaxanthin, a red carotenoid, has been known to possess excellent antioxidant activity and various biological activities, thereby attracting attention as a functional food material.The safety of astaxanthin administered orally has been demonstrated in human clinical studies for about ten years.In this review, we summarized the clinical studies related to safety, as well as studies on genotoxicity, and acute and subchronic toxicity, with a focus on AstaREAL, an astaxanthin product derived from Haematococcus pluvialis which has been reported in numerous human clinical studies to be safe and to have multiple health benefits.Furthermore, based on the latest research, we reviewed the effect of astaxanthin on drug-metabolizing enzymes involved in drug interactions, and concluded that the safety of H. pluvialis-derived astaxanthin, AstaREAL has been widely confirmed.

We treated 162 patients by isolated CABG with a left internal thoracic artery (LITA) anastomosed to the left anterior descending artery and a radial artery anastomosed to the circumflex artery between August 1996 and December 2002. Late angiograms were performed 6 to 65 months (21.7±15.8) after the operation. The purpose of this study was to compare midterm results of radial arteries anastomosed to the side wall of LITA (group Y) with those anastomosed to the aorta (group AC). There were no operative deaths in either group and no difference in the postoperative complication rate including cerebral infarction. The early patency of group Y was lower than that of group AC (group AC: 97.8%, group Y: 87.1%, p=0.017), and also the late patency of group Y was significantly lower than that of group AC (group AC: 90.9%, group Y: 36.4%, p=0.0008). All of the early patent radial artery grafts in group AC were patent on late angiograms, but 3 of the 25 anastomoses in group Y which were clearly patent on early angiograms later showed a string sign later. When using a radial artery graft in circumflex artery territory, we recommend an aorto-coronary bypass graft rather than Y-graft.

Scrotal hematocele is defined as retention of blood in the tunica vaginalis. Although it is usually an acute change, it can also have a chronic course. A 55-year-old man was being treated for hypertension and diabetes in the Department of Internal Medicine at our hospital. He visited the hospital’s Department of Urology because 3 months earlier he had noticed enlargement of the right scrotum without trauma to the perineum. The right scrotum was swollen to the size of a small child’s head. Imaging examination showed no testicular tumor. Puncture yielded 550 ml of bloody fluid. Surgery was performed to find and treat the source of bleeding. The tunica vaginalis was highly irregular and thickened. Considering the possibility of mesothelioma or other malignancy, we removed the testis after transection of the spermatic cord as proximally as possible. The histopathological diagnosis was encapsulated hematoma with cholesterin granuloma, which was diagnosed as chronic scrotal hematocele.

Our extensive basic research on photodynamic therapy (PDT) application in models of intracranial malignant astrocytoma led to its clinical application for intracranial malignant astrocytoma in Japan. Having considered the safety and effectiveness of this pathology, we initiate a first-in-human clinical study of PDT for spinal cord malignant astrocytoma. This study has an open-label, single-arm design. The initial follow-up period is 12 months, at the end of which we will quantify survival after PDT for spinal cord malignant astrocytoma as primary objective. The secondary objective is to quantify the overall progression-free survival of treated patients and the percentage of patients surviving 6 months after PDT without recurrence. Twenty patients suffering from spinal cord malignant astrocytoma will be recruited. In particular, 10 of those should be newly diagnosed World Health Organization grade 4. After obtaining consent, each patient will receive a single intravenous injection of talaporfin sodium (40 mg/m2) 1 day before tumor resection. One day after completing tumor removal, the residual lesion and/or resection cavity will be irradiated using a 664-nm semiconductor laser with a radiation power density of 150 mW/cm2 and a radiation energy density of 27 J/cm2. The procedure will be performed 22–26 hours after talaporfin sodium administration. This study protocol has been reviewed and approved by the Certified Committee in the Japanese Ministry of Health, Labor, and Welfare University Hospital Medical Information Network Clinical Trials Registry (Japan Registry of Clinical Trials number, jRCT2021220040).

Our extensive basic research on photodynamic therapy (PDT) application in models of intracranial malignant astrocytoma led to its clinical application for intracranial malignant astrocytoma in Japan. Having considered the safety and effectiveness of this pathology, we initiate a first-in-human clinical study of PDT for spinal cord malignant astrocytoma. This study has an open-label, single-arm design. The initial follow-up period is 12 months, at the end of which we will quantify survival after PDT for spinal cord malignant astrocytoma as primary objective. The secondary objective is to quantify the overall progression-free survival of treated patients and the percentage of patients surviving 6 months after PDT without recurrence. Twenty patients suffering from spinal cord malignant astrocytoma will be recruited. In particular, 10 of those should be newly diagnosed World Health Organization grade 4. After obtaining consent, each patient will receive a single intravenous injection of talaporfin sodium (40 mg/m2) 1 day before tumor resection. One day after completing tumor removal, the residual lesion and/or resection cavity will be irradiated using a 664-nm semiconductor laser with a radiation power density of 150 mW/cm2 and a radiation energy density of 27 J/cm2. The procedure will be performed 22–26 hours after talaporfin sodium administration. This study protocol has been reviewed and approved by the Certified Committee in the Japanese Ministry of Health, Labor, and Welfare University Hospital Medical Information Network Clinical Trials Registry (Japan Registry of Clinical Trials number, jRCT2021220040).

Our extensive basic research on photodynamic therapy (PDT) application in models of intracranial malignant astrocytoma led to its clinical application for intracranial malignant astrocytoma in Japan. Having considered the safety and effectiveness of this pathology, we initiate a first-in-human clinical study of PDT for spinal cord malignant astrocytoma. This study has an open-label, single-arm design. The initial follow-up period is 12 months, at the end of which we will quantify survival after PDT for spinal cord malignant astrocytoma as primary objective. The secondary objective is to quantify the overall progression-free survival of treated patients and the percentage of patients surviving 6 months after PDT without recurrence. Twenty patients suffering from spinal cord malignant astrocytoma will be recruited. In particular, 10 of those should be newly diagnosed World Health Organization grade 4. After obtaining consent, each patient will receive a single intravenous injection of talaporfin sodium (40 mg/m2) 1 day before tumor resection. One day after completing tumor removal, the residual lesion and/or resection cavity will be irradiated using a 664-nm semiconductor laser with a radiation power density of 150 mW/cm2 and a radiation energy density of 27 J/cm2. The procedure will be performed 22–26 hours after talaporfin sodium administration. This study protocol has been reviewed and approved by the Certified Committee in the Japanese Ministry of Health, Labor, and Welfare University Hospital Medical Information Network Clinical Trials Registry (Japan Registry of Clinical Trials number, jRCT2021220040).

Small cell carcinoma of the prostate is a rare, highly malignant disease with a poor prognosis that often presents with metastatic lesions at the time of diagnosis. A previous study reported that neuroendocrine differentiation occurred during hormonal therapy for prostate cancer and progressed to small cell carcinoma. We encountered one case in which small cell carcinoma was diagnosed at the first visit and another case involving possible neuroendocrine differentiation.