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Abstract Tobacco is a valuable model system for investigating the origin of mitochondrial DNA (mtDNA) in amphidiploid plants and studying the genetic interaction between mitochondria and chloroplasts in the various functions of the plant cell. As a first step, we have determined the complete mtDNA sequence of Nicotiana tabacum. The mtDNA of N. tabacum can be assumed to be a master circle (MC) of 430,597 bp. Sequence comparison of a large number of clones revealed that there are four classes of boundaries derived from homologous recombination, which leads to a multipartite organization with two MCs and six subgenomic circles. The mtDNA of N. tabacum contains 36 protein-coding genes, three ribosomal RNA genes and 21 tRNA genes. Among the first class, we identified the genes rps1 and ψrps14, which had previously been thought to be absent in tobacco mtDNA on the basis of Southern analysis. Tobacco mtDNA was compared with those of Arabidopsis thaliana, Beta vulgaris, Oryza sativa and Brassica napus. Since repeated sequences show no homology to each other among the five angiosperms, it can be supposed that these were independently acquired by each species during the evolution of angiosperms. The gene order and the sequences of intergenic spacers in mtDNA also differ widely among the five angiosperms, indicating multiple reorganizations of genome structure during the evolution of higher plants. Among the conserved genes, the same potential conserved nonanucleotide-motif-type promoter could only be postulated for rrn18-rrn5 in four of the dicotyledonous plants, suggesting that a coding sequence does not necessarily move with the promoter upon reorganization of the mitochondrial genome. [ABSTRACT FROM AUTHOR]

Background: Knee osteoarthritis (KOA) is a chronic joint disease affecting activities of daily living (ADL) and quality of life due to pain and limited range of motion, afflicting a large number of patients worldwide. However, it is difficult to prevent the progression of the disease. Therapeutic strategies for KOA aim to maintain ADL and QOL by alleviating pain or managing locomotive function. Recently, intra-articular injection of platelet-rich plasma (PRP) has been gaining attention. In this study, the clinical results of PRP treatment in our institution were reported and compared between responders and non-responders using patient characteristics and imaging data assessed from plain X-rays and magnetic resonance imaging (MRI)., Methods: Participants in the study were KOA patients with varus deformity assessed as grade 2 or higher in the Kellgren-Lawrence classification who received PRP treatment from January 2022 to November 2023 and were followed up for at least three months. PRP was prepared with 27 mL of blood collected from the patient, and 2.7 mL of PRP was prepared using the PEAK©︎PRP System from DePuy Synthes (Raynham, MA). Intra-articular injections of PRP were performed under echo-guided procedures, and responders or non-responders were determined using the Osteoarthritis Research Society International Standing Committee for Clinical Trials Response Criteria Initiative (OMERACT-OARSI) criteria evaluated by the Japanese Knee Injury and Osteoarthritis Outcome Score (J-KOOS) at three months after PRP injection. The clinical efficacy of PRP treatment for KOA was assessed in this study, and a dichotomous analysis was performed comparing the responder group and the non-responder group using patient characteristics and assessed data from plain X-ray images and MRI to determine prognostic factors for PRP treatment., Results: The study population included 36 knees with a mean age of 70.6. ± 9.2 years, comprising six knees in men and 30 knees in women. The responder group consisted of 16 knees (44.4%), and the non-responder group consisted of 20 knees (55.6%). J-KOOS subscores at pre-treatment elicited that each subscale in the R group was significantly lower than that in the NR group at pretreatment. A dichotomous analysis for the two groups revealed the distribution of sex and past medical history of hyperlipidemia to be significantly different between the two groups. Multivariable logistic regression analysis showed that the coexistence of hyperlipidemia was the main prognostic factor for the efficacy of PRP therapy., Discussion: In this study, comparisons were conducted between responders and non-responders to estimate prognostic factors for the efficacy of PRP therapy. Surprisingly, responders to the treatment tended to show lower J-KOOS scores and to have hyperlipidemia. A literature review revealed conflicting reports on prognostic factors for PRP therapy in KOA, highlighting the need for further research., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2024, Ota et al.)

Background Platelet-rich plasma (PRP) is an autologous product prepared by centrifuging whole blood. PRP is reported to have high tissue repair potential and anti-inflammatory properties. Recently, PRP has become a potential treatment option for osteoarthritis, contributing to pain relief and locomotive improvement. However, the underlying therapeutic mechanisms and key biochemical factors in PRP remain unclear. This study aimed to estimate the major factors for tissue repair involved in PRP treatment by comparing between serum and PRP prepared from the same patients using the Luminex assay. Methodology Blood samples were collected from nine healthy volunteers, and serum and PRP were prepared. PRP was prepared using a PEAK ©︎  PRP SYSTEM kit of DePuy Synthes Mitek Sports Medicine (Raynham, Massachusetts, USA), which is a commercially available PRP preparation kit. The white blood cell count, hemoglobin level, and platelet count were automatically measured for both whole blood and PRP in the hospital's clinical laboratory using the XE-5000™ Automated Hematology System (Sysmex, Kobe, Japan). Comparative analysis of biological factors was then performed using the Luminex assay on serum and PRP. Results PRP was found to have significantly higher white blood cell and platelet counts and lower hemoglobin levels than whole blood. Furthermore, PRP contained significantly higher levels of various factors, including interleukin (IL)-1ra, IL-10, IL-13, C-C motif chemokine ligand (CCL)-2, CCL3, CCL4, CCL8, CCL13, CCL21, C-X-C motif chemokine ligand (CXCL)-10, matrix metalloproteinase (MMP)-3, MMP-9, cluster of differentiation (CD) 40 ligand, vascular endothelial growth factor (VEGF), VEGF-C, platelet-derived growth factor (PDGF)-AB, PDGF-BB, and bone morphogenic protein (BMP)-2. Additionally, IL-1ra and IL-4 showed significant correlations with white blood cell counts in PRP, whereas VEGF had a significant correlation with platelet counts. Conclusions PRP contains various factors in higher quantities than serum. Specifically, the notable increase in the anti-inflammatory cytokine IL-1ra is suggested to play a key role as a major therapeutic mechanism of PRP., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2023, Okumo et al.)

YcjT is a kojibiose phosphorylase found in Escherichia coli. We found that sucrose was a good acceptor of YcjT in reverse phosphorolysis using β-d-glucose 1-phosphate as a donor. The product was identified as β-d-fructofuranosyl α-d-glucopyranosyl-(1→2)-α-d-glucopyranoside. This sugar was also synthesized from sucrose and maltose using YcjT and maltose phosphorylase and promoted the growth of the probiotic Bifidobacterium breve., (© The Author(s) 2023. Published by Oxford University Press on behalf of Japan Society for Bioscience, Biotechnology, and Agrochemistry.)

A series of ( E )-1,2-diaryldigermenes, (Eind)ArGeGeAr(Eind) [Ar = phenyl (2), thiophen-2-yl (3), 9,9-dimethyl-2-fluorenyl (4) and 2,2'-bithiophen-5-yl (5)], supported by the fused-ring bulky 1,1,3,3,5,5,7,7-octaethyl- s -hydrindacen-4-yl (Eind) groups, have been obtained as yellow-orange to red crystalline solids by the reaction of 1,2-dibromodigermene, (Eind)BrGeGeBr(Eind) (1), with ArLi. In the crystals of 2-5, the digermene cores show a flexible nature adopting a trans -bent geometry with the trans -bent angles ( θ ) between the Ge-Ge vector and the C Eind -Ge-C Ar plane of 34.04(12)° (2), 38.3(3)° and 38.8(3)° (3), 33.69(12)° (4) and 39.30(13)° (5). In the UV-vis spectra, strong π-π* absorptions have been observed with an absorption maximum at 451 nm ( ε = 1.3 × 10 4 ) (2), 455 nm ( ε = 9.7 × 10 3 ) (3), 480 nm ( ε = 1.3 × 10 4 ) (4) and 497 nm ( ε = 1.4 × 10 4 ) (5), retaining the GeGe double bond in solution. The absorption data and DFT calculations provide evidence for the intrinsic π-conjugation between the GeGe chromophore and aromatic rings involving the narrowing of the HOMO-LUMO gaps (Δ E ) with the extension of the carbon π-electron systems.

Eugenol is contained in several plants including clove and is thought to exert an analgesic effect. It has been suggested that the slow ventral root potential induced by ipsilateral dorsal root stimulation in the isolated (typically lumbar) spinal cord of newborn rats reflects the nociceptive response, and this in vitro experimental model is useful to assess the actions of analgesics. To further elucidate neuronal mechanisms of eugenol-induced analgesia, we examined the effects of extracellularly applied eugenol on the nociceptive spinal reflex response. To evaluate the effects of eugenol on putative nociceptive responses, the ipsilateral fifth lumbar (L5) dorsal root was stimulated using a glass suction electrode, and the induced reflex responses were recorded from the L5 and twelfth thoracic (Th12) ventral roots in spinal cord preparations (Th10-L5) from newborn rats (postnatal day 0-3). We found that eugenol (0.25-1.0 mM) caused dose-dependent attenuation of the reflex response and also depressed spontaneous ventral root activity. We also found that the slow ventral root potential was further divided into two components: initial and late components. A lower concentration of eugenol selectively depressed the late component. The inhibitory effects by 1.0 mM eugenol were not reversed by 10 µM capsazepine (TRPV1 antagonist) or 40 µM HC-030031 (TRPA1 antagonist). The depressive effect of eugenol on the reflex response was also confirmed by optical recordings using voltage-sensitive dye. Our report provides additional evidence on the basic neuronal mechanisms of eugenol to support its clinical use as a potential analgesic treatment.

Tobacco is a valuable model system for investigating the origin of mitochondrial DNA (mtDNA) in amphidiploid plants and studying the genetic interaction between mitochondria and chloroplasts in the various functions of the plant cell. As a first step, we have determined the complete mtDNA sequence of Nicotiana tabacum. The mtDNA of N. tabacum can be assumed to be a master circle (MC) of 430,597 bp. Sequence comparison of a large number of clones revealed that there are four classes of boundaries derived from homologous recombination, which leads to a multipartite organization with two MCs and six subgenomic circles. The mtDNA of N. tabacum contains 36 protein-coding genes, three ribosomal RNA genes and 21 tRNA genes. Among the first class, we identified the genes rps1 and psirps14, which had previously been thought to be absent in tobacco mtDNA on the basis of Southern analysis. Tobacco mtDNA was compared with those of Arabidopsis thaliana, Beta vulgaris, Oryza sativa and Brassica napus. Since repeated sequences show no homology to each other among the five angiosperms, it can be supposed that these were independently acquired by each species during the evolution of angiosperms. The gene order and the sequences of intergenic spacers in mtDNA also differ widely among the five angiosperms, indicating multiple reorganizations of genome structure during the evolution of higher plants. Among the conserved genes, the same potential conserved nonanucleotide-motif-type promoter could only be postulated for rrn18-rrn5 in four of the dicotyledonous plants, suggesting that a coding sequence does not necessarily move with the promoter upon reorganization of the mitochondrial genome.

Purpose: Myocardial opacification is not always homogeneous even in a normal heart. The aim of this study is to clarify why myocardial opacification is faint at the lateral side of the field or at the part far from the focus point., Methods: In canine study, videointensity of the opacification at septal and lateral walls of the short axis view was examined by using both electric and mechanical transducers. In in vitro study, acoustic pressure at several points away from the beam direction was measured using a hydrophone in a water tank. In particular, the effect of position of focus point was evaluated with an electronic transducer., Results: In canine experiment, myocardial opacification of the lateral wall was faint with the electronic transducer, however the mechanical one obtained homogeneous opacification. In vitro, using the electronic type the acoustic pressure was low as the beam shifted, laterally, whereas it was almost uniform in the mechanical type. With the electronic type, moreover, the beam width at the near field was not sharp when the focus point was far, resulting in execessive acoustic pressure., Conclusion: To obtain homogeneous opacifiction, a homogeneous acoustic field is indispensable.

Objectives: Myocardial contrast echocardiography observes heterogeneous opacification between regions near and far from the transducer depending on the depth of the focus point. The efficacy of the multi-focus setting was investigated for the improvement of this heterogeneous opacification of the myocardium in myocardial contrast echocardiography., Methods: Myocardial contrast echocardiography was performed in five closed-chest dogs using triggered (every fourth cardiac cycle) second harmonic technology (1.8/3.6 MHz) following intravenous injection of 0.1 ml of Optison. The short-axis view of the left ventricle was recorded and baseline subtracted video intensity (peak intensity) was calculated in the anterior, septal and posterior left ventricular walls to evaluate myocardial opacification. Three different single foci at near (2 cm), middle (4 cm), and far (6 cm) points were examined, as well as the multi-focus setting combining the near and far foci., Results: Using any single focus point, the peak intensities of segments far from the focus points were decreased and heterogeneous myocardial opacification was observed. Only the multi-focus setting demonstrated absence of differences in peak intensities between each segment with sufficient myocardial opacification of all segments., Conclusions: The multi-focus setting may be advantageous for improving the heterogeneity of myocardial opacification in myocardial contrast echocardiography.

Objectives: Levovist can opacify the myocardium via venous injection, and is widely used in the clinical field. However, left ventricular opacification deteriorates during oxygen inhalation using Albunex, one of the first generation of contrast agents. This study examines the effect of blood oxygen pressure on the myocardial opacification by Levovist., Methods: Myocardial contrast echocardiography (Toshiba Power Vision 6000) was performed using second harmonic imaging, intermittent exposure of ultrasound (every 4 cardiac beats) and acoustic power of 1.4 mechanical index. The video intensity of the ventricular septum after venous injection of Levovist (0.5 ml of 300 mg/ml) was measured under various respiratory conditions by manipulating the respirator and oxygen inhalation. Arterial blood gas was measured and correlated with the myocardial video intensity., Results: The video intensity of myocardial opacification was lower with higher oxygen pressure in the arterial blood. Visual recognition of myocardial opacification was only 14% under high oxygen pressure over 200 mmHg. Microbubbles of Levovist form from normal air, and are easily affected by the gas concentration of the surrounding blood., Conclusions: Myocardial opacification using Levovist is deteriorated under high oxygen pressure at examination.

Objectives: Myocardial contrast echocardiography is useful to assess myocardil perfusion, but myocardial opacification is affected by the setup of the ultrasonic equipment. The optimal setting of focus points for adequate opacification of the myocardium was examined in myocardial contrast echocardiography., Methods: Myocardial contrast echocardiography was performed in six dogs using triggered second harmonic technology following intravenous administration of Optison(FS-69). The short-axis view was recorded and baseline subtracted video intensity(peak intensity: PI) was calculated at three regions of the left ventricular wall, the anterior, septum, and posterior walls, to evaluate myocardial opacification. The focus point was set at near(2 cm), middle(4 cm) and far(6 cm)points. The myocardial opacification was evaluated at each focus setting. The effect of the acoustic power was also examined by changing the mechanical index to 1.6, 1.2 or 0.8., Results: Myocardial opacification was recognized at all focus points, and segments near the focus points had high PI. However, the PI of the posterior wall was lowest at near focus, whereas the PI of the anterior wall was lowest at far focus. The difference of PI between the anterior and posterior walls was significant (p < 0.05, p < 0.01, respectively) at either focus point. Adequate myocardial opacification of all segments was observed when the focus was set at the middle point. The PI of the whole left ventricle increased relative to mechanical index., Conclusions: Setting up of focus points at the middle of the left ventricle provides more homogeneous myocardial opacification of the whole left ventricle in myocardial contrast echocardiography, and high acoustic power possibly improves myocardial opacification. Inadequate setting of focus points leads to inadequate estimation of myocardial perfusion by myocardial contrast echocardiography.

Objectives: Few intravenous myocardial contrast echocardiography trials have evaluated myocardial perfusion in small animals. The feasibility of using intravenous myocardial contrast echocardiography to assess the ischemic area in rats was investigated., Methods: Fourteen open chest Wister male rats were examined. Intravenous myocardial contrast echocardiography was performed by fundamental and intermittent mode using a high frequency (5-12 MHz) transducer (SONOS 5500) with injection of NC100100 (20% dilution) into the femoral vein. The mechanical index was set to 1.6. Baseline-subtracted video intensity (256 level) was measured in the anterior, posterior, septal and lateral walls of the left ventricle. The left anterior descending artery was ligated in 16 rats. The area at risk was evaluated by myocardial contrast echocardiography and compared to the area of defect by Evans Blue staining., Results: All wall segments were clearly opacified (anterior 63.8 +/- 24.7, posterior 27.0 +/- 11.0, septal 44.5 +/- 11.6, lateral 52.3 +/- 19.1), although the baseline-subtracted video intensity of the posterior wall was low. The area at risk was clearly observed, and there was a good correlation with the nonperfused area by Evans Blue staining (y = 1.13x-3.54, r = 0.98)., Conclusions: Intravenous myocardial contrast echocardiography can detect the perfusion defect even in rats using a high frequency transducer and suitable setup of equipment.

Background: In the Japan Air Self Defense Force (JASDF), new vision standards for student pilots allow lower uncorrected monocular acuity (from 1.0 to 0.8). In flight environments, where the use of corrective lenses may present problems, the risk of decreasing visual acuity in pilots who should wear corrective lenses must be defined., Methods: We conducted a 25-yr prospective study of visual acuity with regard to distance vision in 752 JASDF nonaviation personnel followed from ages 20 to 45. The test subjects were divided into four groups according to their right monocular visual acuity at entry: > or =1.0, between 0.9 and 0.7, between 0.6 and 0.2, and <0.2., Results: At entry, 94.1% of all subjects had visual acuity > or =0.7. The proportion of subjects who required corrective lenses for distance increased with age from 15.8% to 37.1%. After 25-yr, 30.2% of subjects with visual acuity > or =1.0 at entry and 62.7% of subjects with visual acuity between 0.9 and 0.7 at entry required corrective lenses., Conclusions: Over 25 yr, the population with the best eyesight at age 20 had a lower increase in the need for corrective lenses than the population with visual acuity between 0.9 and 0.7 at age 20. These results suggest an increased risk of visual acuity loss in pilots over time as a result of the lower vision standards for student pilots in the JASDF.

High altitude hypoxia is known to cause pulmonary hypertension in humans. Altitudes of 5500 m and 4000 m above sea level are considered to be the upper limits for short-term human survival and long-term human residence, respectively. To study the effects of hypobaric-hypoxic environments on pulmonary vascular beds, the physiologic and morphometric differences occurring in the pulmonary arteries of rats at the equivalent of these two altitude levels were compared. One hundred and ninety male rats were housed in a double-roomed mechanical chamber and subjected for 12 weeks to hypobaric-hypoxic environments equivalent to an altitude level of 5500 m or 4000 m. After 6-8 weeks, mean pulmonary arterial pressure (PAPm) was significantly higher in rats at the 5500 m level than in those at 4000 m. The external diameter of muscular arteries (M) and of partially muscular arteries (PM) in the lungs of rats at 8 and 12 weeks, and those of nonmuscular arteries (NM) around the alveolar sacs at 2 and 8 weeks were each significantly less in rats exposed to the 5500 m level than in those at 4000 m. At 4 weeks, the ratio of medial thickness to external diameter for M and PM around the alveolar ducts and alveolar sacs were greater in rats exposed to the 5500 m level than in those at 4000 m. Erythrocyte count, hemoglobin and hematocrit tests showed polycythemic patterns during the initial hypobaric period in both 5500 m-, and 4000 m-level rats. However, from 4 to 12 weeks, the hematologic values of the 4000 m-level rats declined progressively toward the upper end of the normal range. This study suggests (i) that elevated PAPm in rats exposed to hypobaric-hypoxic environments results from structural remodeling of all M, PM and NM within the lobule, and (ii) that an environment equivalent to the 5500 m level causes more severe pulmonary vascular changes than one equivalent to the 4000 m level. The hematologic results suggest that rats exposed to the equivalent of the upper limit for long-term human residence can acquire acclimatization, but not those exposed to the equivalent of the upper limit for short-term human survival.

1. The present study was undertaken to investigate the effects of hypobaric hypoxia, equivalent to an altitude of 5500 m, on antioxidant enzymes in rats. 2. Malondialdehyde levels in serum, heart, lung, liver and kidney of hypobaric-hypoxic rats were all significantly higher than in control rats by day 21 of exposure (P < 0.05), indicating increased oxidative stress. 3. Superoxide dismutase (SOD) catalyses the conversion of the superoxide anion to H2O2 and O2. The concentration of immunoreactive Mn-SOD in the serum of hypobaric-hypoxic rats was raised significantly from day 5 onwards, whereas in liver and lung, it had decreased significantly by day 21 (P < 0.05). 4. Glutathione peroxidase (GSH-Px) catalyses H2O2 and certain lipid peroxides. By day 21, GSH-Px activity had increased significantly in the heart and lungs, but decreased significantly in the liver (P < 0.05). 5. Catalase catalyses H2O2. Catalase activity in the liver and kidney of hypobaric-hypoxic rats was significantly decreased on day 1 (P < 0.05) though levels then recovered. 6. Mn-SOD mRNA in the liver of hypobaric-hypoxic rats was induced during the experiment, the effect being exceptionally marked, especially during the first 3 days of exposure to hypobaric hypoxia. 7. These results suggest that the liver may be more vulnerable than the other organs tested to oxidative stress under hypobaric hypoxia.

The introduction of the F-15 Eagle to the Japan Air Self Defense Force (JASDF) in the early 1980's seemed to increase musculoskeletal problems of the spinal column among pilots. The neck is the body part most vulnerable to high-G force injuries, and serious cases of neck injury have been reported. We surveyed 129 F-15 pilots from different air bases by means of a questionnaire. The occurrence rate of musculoskeletal problems in different types of aircraft was analyzed according to the pilots' flying experience. Of the surveyed pilots, 115 (89.1%) reported muscle pains related to flying. Of those who experienced pain, each averaged 7.6 events, 95% of which occurred in the F-15. Of these 115, 30% experienced pain in the F-4 and 15% in the F-1. The "checking six" position was the most common posture at the time of injury, followed by "forward bend." Of the 115 pilots, 44 stated that their symptoms adversely affected flight duty performance, and 50 pilots stated that their symptoms adversely affected daily life. The effectiveness of muscle training as a preventive measure was supported by 62%. Some oriental therapeutic methods (acupuncture, moxa cautery, and finger-pressure massage) were preferred by pilots for pain treatment. G-related problems of the spinal column still exist as a major medical concern in JASDF.

The Japanese Air Self Defense Force has been conducting high-G training to enhance the +Gz tolerance of F-15 and F-4 fighter pilots since 1981. All the trainees have received ECG monitoring during the +Gz stress, both for safety and for medical evaluation. Various arrhythmias have been found previously, but most of the pilots who developed them were qualified for fighter aircraft because these arrhythmias were considered as non-hazardous for flight safety. Rarely, cases of aeromedically "serious" arrhythmias were observed with alteration of consciousness during the centrifuge ride. Three cases of sinoatrial block and one case of ventricular tachycardia were reviewed with their aeromedical dispositions. Imbalance of autonomic nerves induced by high +Gz is discussed as a possible etiology. The importance of ECG monitoring during centrifuge training is reemphasized as a means of medical evaluation of fighter pilots.