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Toshiyuki Takemori,1 Teruya Kawamoto,1,2 Hitomi Hara,1 Naomasa Fukase,1 Shuichi Fujiwara,1 Kazumichi Kitayama,1 Shunsuke Yahiro,1 Tomohiro Miyamoto,1 Yutaka Mifune,1 Yuichi Hoshino,1 Kenichiro Kakutani,1 Tomoyuki Matsumoto,1 Takehiko Matsushita,1 Takahiro Niikura,1 Ryosuke Kuroda,1 Toshihiro Akisue1,3 1Department of Orthopaedic Surgery, Kobe University Graduate School of Medicine, Kobe, Japan; 2Division of Orthopaedic Surgery, Kobe University Hospital International Clinical Cancer Research Center, Kobe, Japan; 3Department of Rehabilitation Science, Kobe University Graduate School of Health Sciences, Kobe, JapanCorrespondence: Teruya Kawamoto, Department of Orthopaedic Surgery, Kobe University Graduate School of Medicine, 7-5-1, Kusunoki-cho, Chuo-ku, Kobe, 650-0017, Japan, Tel +81-783825985, Fax +81-783516944, Email trykwmt@med.kobe-u.ac.jpPurpose: Soft tissue sarcomas (STSs) constitute a group of rare, heterogeneous tumors representing approximately 1% of all cancers. Owing to the rarity and pathological diversity of the disease, unplanned excision (UE) has often been performed for STS, resulting in an unfavorable prognosis. This study aimed to clarify clinical outcomes and prognostic factors in STS patients who underwent UE.Patients and Methods: In a retrospective review of the medical records of patients with STS who underwent surgery at our institution between 1999 and 2015, patients were enrolled to either a UE group or a planned excision (PE) group. An analysis was then conducted to identify factors associated with prognosis after UE.Results: Of 134 patients undergoing surgery for STS, 110 were enrolled to the PE group and 24 to the UE group. The median size of the primary tumor was significantly smaller, and more lesions were located in the superficial layer in the UE group than in the PE group. In addition, plastic reconstruction after additional radical resection was required significantly more often in the UE group than in the PE group. No significant difference in overall survival, local recurrence-free survival, or disease-free survival (DFS) between the UE and PE groups was observed; however, metastasis-free survival was significantly better in the UE group. In the UE group, poorer DFS was associated with older age (≥ 61 years) and a larger primary tumor (≥ 2.9 cm).Conclusion: A prognosis similar to that in patients undergoing PE could be achieved by appropriate additional surgeries in patients initially undergoing UE. However, UE for STS should be avoided, especially in older patients and those with a larger primary tumor.Keywords: unplanned excision, soft tissue sarcoma, survival, prognostic factor

Objective: In the largest avascular low-nutrient intervertebral disc, resident cells would utilize autophagy, a stress-response survival mechanism by self-digestion and recycling wastes. Our goal was to elucidate the involvement of autophagy in disc homeostasis through RNA interference of autophagy-related gene 5 (Atg5).Design: In vitro, small interfering RNAs (siRNAs) targeting autophagy-essential Atg5 were transfected into rat disc cells. Cell viability with levels of autophagy including Atg5 expression, apoptosis, and senescence was assessed under serum starvation and/or pro-inflammatory interleukin-1 beta (IL-1β) stimulation. In vivo, time-course autophagic flux was monitored following Alexa Fluor® 555-labeled Atg5-siRNA injection into rat tail discs. Furthermore, 24-h temporary static compression-induced disruption of Atg5 siRNA-injected discs was observed by radiography, histomorphology, and immunofluorescence.Results: In disc cells, three different Atg5 siRNAs consistently suppressed autophagy with Atg5 protein knockdown (mean 44.4% [95% confidence interval: -51.7, -37.1], 51.5% [-80.5, -22.5], 62.3% [-96.6, -28.2]). Then, Atg5 knockdown reduced cell viability through apoptosis and senescence not in serum-supplemented medium (93.6% [-0.8, 21.4]) but in serum-deprived medium (66.4% [-29.8, -8.6]) further with IL-1β (44.5% [-36.9, -23.5]). In disc tissues, immunofluorescence detected intradiscal signals for the labeled siRNA even at 56-d post-injection. Immunoblotting found 56-d autophagy suppression with prolonged Atg5 knockdown (33.2% [-52.8, -5.3]). With compression, Atg5 siRNA-injected discs presented radiographic height loss ([-43.9, -0.8]), histological damage ([-5.5, -0.2]), and immunofluorescent apoptosis ([2.2, 22.2]) and senescence ([4.1, 19.9]) induction compared to control siRNA-injected discs at 56 d.Conclusions: This loss-of-function study suggests Atg5-dependent autophagy-mediated anti-apoptosis and anti-senescence. Autophagy could be a molecular therapeutic target for degenerative disc disease. [ABSTRACT FROM AUTHOR]

The ablation phenomena in silica glass were investigated using a visible femtosecond laser and time-resolved pump-probe imaging. A pump pulse with a wavelength of 400 nm was employed. Only gentle ablation occurred at a peak fluence of 6.88 J/cm2, and gentle ablation and strong ablation occurred at a peak fluence of 8.23 J/cm2. At both peak fluences, reflectivity increased owing to excitation at a delay time of ~1 ps. At a delay time of ~30 ps, a decrease in reflectivity due to melting was observed only at the local fluence that generated strong ablation. The ablation that occurred after melting was considered to correspond to strong ablation. Similar changes in reflectivity were observed for two values of the local fluence that corresponded to gentle ablation. [ABSTRACT FROM AUTHOR]

The longitudinal electric field profile of coherent transition radiation (CTR), which is a radially polarized terahertz (THz) pulse from an electron bunch, was measured using a large-aperture photoconductive antenna (PCA) with a diameter of 8.8 mm and micro-structured concentric electrodes to detect THz light pulses. Photo-induced charge carriers were generated on the PCA by the irradiation of femtosecond laser pulses on the electrode plane. Pulsed light irradiation enabled time-resolved measurement of the THz light pulses, and time-domain measurement of CTR was conducted by measuring the electric-field-induced current output from the PCA by sweeping the timing of the laser irradiation. The frequency spectra obtained from the detected longitudinal electric field profiles of the CTR showed a reasonable response signal from the low-frequency region as low as 0.1 THz. In the present demonstration, the large-aperture PCA-detected THz wave from the CTR was from 0.1 to at least 1 THz. THz generation using the PCA was also performed and measured using a Michelson interferometer with a helium-cooled bolometer. Comparison of the THz pulse of the CTR detected using the PCA and that generated using the PCA revealed that time-domain measurement of the THz pulse using the PCA was limited by the response time of the charge carriers in the semiconductor. Enlargement of the aperture of the PCA enhanced the detectable frequency region toward a lower frequency. [ABSTRACT FROM AUTHOR]