Absolutely Uncontrollable Weapons: An Ethical Approach to Defusing Nuclear Risks

To analyze “Ethics and Peace and Nuclear Weapons,” a critical appraisal ofthe various risks inherent in nuclear weapons systems is indispensable. The logicof deterrence, that nuclear weapons as absolute weapons can maintain peace andstability, has been heard for decades. Whatever rationale this logic may havehad, it has become less credible. Moreover, the unnecessary high-alert status ofnuclear weapons remains, posing the risk of accidental or unintentional nuclearwar. In addition, concerns for proliferation increase as some key technologiesand fissile materials can be used for both civilian and military purposes. Evenlimited or regional nuclear war resulting from proliferation would be disastrousto large populations and the global environment. When considering nuclearrisks, the weaponization of nuclear facilities such as power plants should beaddressed. Weaponization in this context refers to an attack on a nuclear facilityin war or by terrorists to release radioactive material into populated areas andthe environment. Given these nuclear imperatives, this article will (1) review theuncontrollability of risks posed by both military and civilian nuclear systems, (2)describe the inadequacy of humanitarian responses to deal with nuclear risks,and (3) discuss the necessity of the “Ethical Empowerment” of civil society toreframe our arguments on nuclear issues in humanitarian terms and to makenuclear imperatives controllable and ultimately to resolve them

The Third Nuclear Age: Strategies to avoid catastrophic risk

departmental bulletin pape

Crocetin reduces the oxidative stress induced reactive oxygen species in the stroke-prone spontaneously hypertensive rats (SHRSPs) brain

Crocetin is a natural carotenoid compound of gardenia fruits and saffron, which has various effects in biological systems. In this study, we investigated the antioxidant effects of crocetin on reactive oxygen species such as hydroxyl radical using in vitro X-band electron spin resonance and spin trapping. Crocetin significantly inhibited hydroxyl radical generation compared with the control. Moreover, we performed electron spin resonance computed tomography ex vivo with the L-band electron spin resonance imaging system and determined the electron spin resonance signal decay rate in the isolated brain of stroke-prone spontaneously hypertensive rats, a high-oxidative stress model. Crocetin significantly reduced oxidative stress in the isolated brain by acting as a scavenger of reactive oxygen species, especially hydroxyl radical, as demonstrated by in vitro and ex vivo electron spin resonance analysis. The distribution of crocetin was also determined in the plasma and the brain of stroke-prone spontaneously hypertensive rats using high-performance liquid chromatography. After oral administration, crocetin was detected at high levels in the plasma and the brain. Our results suggest that crocetin may participate in the prevention of reactive oxygen species-induced disease due to a reduction of oxidative stress induced by reactive oxygen species in the brain

A possible role for Ca2+/calmodulin-dependent protein kinase IV during pancreatic acinar stimulus–secretion coupling

AbstractCa2+/calmodulin-dependent protein kinases (CaMKs) are important intracellular mediators in the mediation of stimulus–secretion coupling and excitation–contraction coupling in a wide variety of cell types. We attempted to identify and characterize the functional roles of CaMK in mediating pancreatic enzyme secretion. Immunoprecipitation and immunoblotting studies using a CaMKII or CaMKIV antibody showed that rat pancreatic acini expressed both CaMKII and CaMKIV. Phosphotransferase activities of CaMKs were measured by a radioenzyme assay (REA) using autocamtide II, peptide γ and myosin P-light chain as substrates. Although CaMKII and CaMKIV use autocamtide II as a substrate, peptide γ is more efficiently phosphorylated by CaMKIV than by CaMKII. Intact acini were stimulated with cholecystokinin (CCK)-8, carbachol (CCh) and the high-affinity CCK-A receptor agonist, CCK-OPE, and the cell lysates were used for REA. CCK-8, CCh and CCK-OPE caused a concentration-dependent increase in CaMKs activities. When autocamtide II was used, maximal increases were 1.5–1.8-fold over basal (20.2±2.0 pmol/min/mg protein), with peaks occurring at 20 min after cell stimulation. In separate studies that used peptide γ, CCK-8, CCh and CCK-OPE dose-dependently increased CaMKIV activities. Maximal increases were 1.5–2.4-fold over basal (30.7±3.2 pmol/min/mg protein) with peaks occurring at 20 min after cell stimulation. Peak increases after cell stimulation induced by peptide γ were 1.8–2.8-fold higher than those induced by autocamtide II. CCK-8, CCh and CCK-OPE also significantly increased phosphotransferase activities of myosin light chain kinase (MLCK) substrate (basal: 4.4±0.7 pmol/min/mg protein). However, maximal increases induced by MLCK substrate were less than 10% of those occurring in peptide γ. Characteristics of the phosphotransferase activity were also different between autocamtide II and peptide γ. When autocamtide II was used, elimination of medium Ca2+ in either cell lysates or intact cells resulted in a significant decrease in the activity, whereas it had no or little effect when peptide γ was used. This suggests that Ca2+ influx from the extracellular space is not fully required for CaMKIV activity and Ca2+ is not a prerequisite for phosphotransferase activity once CaMKIV is activated by either intracellular Ca2+ release or intracellular Ca2+ oscillations. The specific CaMKII inhibitor KN-62 (50 μM) had no effect on the CaMKIV activity and pancreatic enzyme secretion elicited by CCK-8, CCh and CCK-OPE. The specific MLCK inhibitor, ML-9 (10 μM), also did not inhibit CCK-8-stimulated pancreatic amylase secretion. In contrast, wide spectrum CaMK inhibitors, K-252a (1 μM) and KT5926 (3 μM), significantly inhibited CaMKIV activities and enzyme secretion evoked by secretagogues. Thus, CaMKIV appears to be an important intracellular mediator during stimulus–secretion coupling of rat pancreatic acinar cells

Direct assessment by electron spin resonance spectroscopy of the antioxidant effects of French maritime pine bark extract in the maxillofacial region of hairless mice

Flavangenol, one of extract of French maritime pine bark, is a complex mixture of bioflavonoids with oligometric proanthocyanidins as the major constituents. These constituents, catechin and procyanidin B1, are water-soluble derivatives of flavangenol. In this study, we investigated the antioxidant effects of flavangenol on reactive oxygen species such as hydroxyl radical, superoxide anion and singlet oxygen using electron spin resonance and spin trapping. The effect of flavangenol on oxidative stress in the skin from the maxillofacial region of hairless mice was investigated using an in vivo L-band electron spin resonance imaging system. Flavangenol attenuated oxidative stress in the maxillofacial skin by acting as a reactive oxygen species scavenger, as demonstrated by in vitro and in vivo electron spin resonance imaging analysis. The absorption and metabolism of flavangenol were also examined. After oral administration of flavangenol in human and rat, most of the catechin in plasma was in the conjugated form, while 45% to 78% of procyanidin B1 was unconjugated, indicating that non-conjugated procyanidin B1 would be active in the circulation. The ability of flavangenol to reduce reactive oxygen species levels in the circulation of the maxillofacial region suggests that this extract may be beneficial for skin protection from exposure to ultraviolet irradiation

ニューラル・ネットワーク・モデルによる日本語文節の識別の試み

Recognizing that clauses in Japanese tend to end with a relatively limited number of letters, this study attempted to recognize ends of clauses in written Japanese by a neural network model with back propagation. Focusing on ten letters which are most likely to be used as a last letter in Japanese clauses, this study set up a neural network model to learn to tell whether or not an encountered letter (target letter) was used as an ending letter of a clause. Although only a partial tests were attempted due to the relatively small sizes of the data sets, the obtained results were quite encouraging. Based on the findings, this study suggests four points of further improvement: (1) an enlargement of volume of data set, (2) an improvement of data generation method, (3) an examination of cases which were not properly recognized, and (4) a possible use of a certain type of dictionary as well as an inclusion of grammatical rules

Image-guided core needle biopsy for musculoskeletal lesions

Background: Image-guided percutaneous core needle biopsy (CNB) has been an important diagnostic procedure for musculoskeletal lesions. Here we surveyed the variety of diagnostic strategies available and assessed the clinical usefulness and limitations of image-guided CNB carried out by a multidisciplinary team comprising specialists in various fields. Methods: We conducted a retrospective study of 284 image-guided CNBs among 1899 consecutive biopsy procedures carried out at our institution for musculoskeletal tumorous conditions, focusing on their effectiveness including diagnostic accuracy and utility for classification of specimens according to malignant potential and histological subtype as well as their correlation with biopsy routes. Results: Among the 284 studied biopsies, 252 (88.7%) were considered clinically “effective”. The sensitivity for detection of malignancy was 94.0% (110/117) and the specificity was 95.3% (41/43). The diagnostic accuracy for detection of malignancy was 94.4% (151/160) and that for histological subtype was 92.3% (48/52). The clinical effectiveness of the procedure was correlated with the complexity of the biopsy route (P = 0.015); the trans-pedicular, trans-retroperitoneal and trans-sciatic foramen approaches tended to yield ineffective results. Repeat biopsy did not have a significant impact on the effectiveness of image-guided CNB (P = 0.536). Conclusions: The diagnostic accuracy rates of image-guided CNB performed at multidisciplinary sarcoma units were usable even for patients who have variety of diagnostic biopsy procedures. It is important to establish and implement diagnostic strategies based on an understanding that complicated routes, especially for spine and pelvic lesions, may be associated with ineffectiveness and/or complications