The Influence of Polyploidy and Genome Composition on Genomic Imprinting in Mice

Genomic imprinting is an epigenetic mechanism that switches the expression of imprinted genes involved in normal embryonic growth and development in a parent-of-origin-specific manner. Changes inDNAmethylation statuses from polyploidization are a well characterized epigenetic modification in plants. However, how changes in ploidy affect both imprinted gene expression and methylation status in mammals remains unclear. To address this, we used quantitative real time PCR to analyze expression levels of imprinted genes in mouse tetraploid fetuses. We used bisulfite sequencing to assess the methylation statuses of differentially methylated regions (DMRs) that regulate imprinted gene expression in triploid and tetraploid fetuses. The nine imprinted genes H19, Gtl2, Dlk1, Igf2r, Grb10, Zim1, Peg3, Ndn, and Ipw were all unregulated; in particular, the expression of Zim1 was more than 10-fold higher, and the expression of Ipw was repressed in tetraploid fetuses. The methylation statuses of four DMRs H19, intergenic (IG), Igf2r, and Snrpn in tetraploid and triploid fetuses were similar to those in diploid fetuses. We also performed allele-specific RT-PCR sequencing to determine the alleles expressing the three imprinted genes Igf2, Gtl2, and Dlk1 in tetraploid fetuses. These three imprinted genes showed monoallelic expression in a parent-of-origin-specific manner. Expression of non-imprinted genes regulating neural cell development significantly decreased in tetraploid fetuses, which might have been associated with unregulated imprinted gene expression. This study provides the first detailed analysis of genomic imprinting in tetraploid fetuses, suggesting that imprinted gene expression is disrupted, but DNA methylation statuses of DMRs are stable following changes in ploidy in mammals

Development of a Prelude Satellite Equipped with Electric Field and Plasma Measurement Sensors Based on Statistical Evaluation of Seismic Precursors Using Artificial VLF Radio Waves Obtained from In-Orbit Observations

In this paper, we focus on the artificial VLF radio wave and show the result of the evaluation of the signal intensity decrease by the effect of ionospheric fluctuation, which is regarded as a sign phenomenon of earthquake occurrence. This paper also describes the mission design of Prelude (Precursor electric field observation CubeSat demonstrator) which is aiming at elucidation of the precursory mechanism of earthquake, and the development situation of hybrid sensor (electric field and plasma measurement) which is a mission instrument. We focused on the artificial VLF wave, in which the electromagnetic wave itself does not affect the ionosphere, and examined the relationship between the degree of electric field intensity decrease by the artificial VLF wave and the magnitude of the earthquake. And, by using lightning data of WWLLN (World Wide Lightning Location Network), the relation between change of generation number and energy and earthquake was evaluated. We have developed a CubeSat (6U Size) that is easy to mass-produce. However, the electric field measuring instrument and plasma measuring instrument mounted on the Demeter (130 kg large satellite) are each more than 1U in size. There are also no sensors for CubeSats that can be observed simultaneously. Therefore, we are working on the development of the hybrid sensor of 1U size or less which can measure electric field and plasma simultaneously on the orbit

Design and Development of Prelude, Satellite for Seismic Precedence Detection and Verification Using VLF Radio Waves for Navigation Obtained in Orbit

In this study, we analyzed the ionospheric anomaly in the D region, which precedes the occurrence of earthquakes, by focusing on the VLF radio wave for navigation, which is used for military communication, among the observation data of the earth observation satellite DEMETER (Detection of Electro-Magnetic Emissions Transmitted from Earthquake Regions). We analyzed the ionospheric anomaly in the D region that occurs prior to an earthquake. Next, based on the results, we propose the design of a 6U nano-satellite dedicated to the detection of earthquake precursory phenomena using navigational VLF radio waves: Prelude (Precursory electric field observation CubeSat demonstrator). The design of Prelude (Precursory electric field observation CubeSat demonstrator) is proposed. In a previous study, the authors of Němec, Kamogawa et al. attributed this decrease in intensity to an increase in electron density in the D region. Kamogawa et al. attributed this decrease to an increase in electron density in the D region. Based on these results, our proposed satellite mission will be to observe ionospheric anomalies in the D-region that precede earthquakes for the purpose of short-term earthquake prediction in the future. Němec et al. and Kamogawa et al. have studied the variation of electron density in the D region by analyzing the radio waves generated by lightning. However, the accuracy of this method is limited for the following three reasons: 1) the frequency of lightning is different depending on the season, 2) the frequency range of lightning is wider than that of thunderstorms, and 3) there are dispersion characteristics of radio waves due to ionospheric plasma. Therefore, in this study, we focused on the variation of electron density in the D region by focusing on the VLF charged wave for navigation, which has a constant frequency, continuous transmission, and temporal and spatial continuity. As a case study analysis, we confirmed the validity of the analysis of navigational VLF waves by focusing on the earthquake in southern Sumatra. The results show that the navigational VLF signal intensity decreases significantly before the earthquake compared to the trajectories in the comparison counties. This suggests that the effects of ionospheric fluctuations shown by Němec In addition, we found that the VLF radio wave strength of Prelude was significantly reduced before the earthquake. Furthermore, this study showed the effectiveness of navigational VLF radio waves as a new analysis target for Prelude\u27s mission analysis. Therefore, we considered that there is a room to introduce a flexible system for the design and development of the science mission during the design and development of this satellite by using Systems Modeling

Musculo-cutaneous flap for reconstruction surgery for deep surgical site infection after total en bloc spondylectomy: A technical note

BackgroundTotal en bloc spondylectomy (TES) is potential radical resection surgery for spinal tumors. Surgical procedure of TES includes extremely wide detachment of surrounding soft tissue from pathological vertebra, resulting in impairment of blood supply. Moreover, massive dead space inevitably is made after vertebral body resection. Therefore deep surgical site infection (SSI) after TES could be intractable. To date, suitable treatment for deep SSI after TES has not been established.Case descriptionA 72 years old man underwent TES of 12th thoracic level via single posterior approach for primary leiomyosarcoma. Postoperative additional irradiation was performed. One year after surgery, late infection around the cage occurred. We removed the cage followed by autologous iliac bone grafting, we treat the wound by open therapy and daily irrigation, followed by negative pressure wound therapy. Four-month later, we performed musculo-cutaneous flap using latissimus dorsi muscle with plastic surgeons. At the follow-up visit one year after flap surgery, no evidence of recurrence of infection was observed.ConclusionMusculo-cutaneous flap is one of treatment options to fill the dead space and to control deep SSI after TES

Limitations in the use of rifampicin-gelatin grafts against virulent organisms

AbstractObjective: Efficacy and duration of antibacterial activity of rifampicin-gelatin grafts against virulent organisms were evaluated in an animal model. Materials and Methods: Rifampicin-gelatin grafts were prepared with impregnation of Gelseal (Vascutek Ltd, Scotland) graft in 1 mg/mL rifampicin solution. Rifampicin-gelatin grafts (6 cm long; n = 24) and plain Gelseal grafts as controls (n = 4) were implanted into the canine abdominal aorta with inoculation of Staphylococcus epidermidis, Escherichia coli, or methicillin-resistant Staphylococcus aureus (MRSA), and the rifampicin-gelatin grafts were retrieved after 1 to 4 weeks. Disks cut from the retrieved rifampicin-gelatin grafts were placed on agar plates streaked with one of the organisms, and the graft antibacterial activity was assessed with the width of the inhibition zone. Results: In in vitro tests, initial inhibition zones (inhibition zone of 24 hours after incubation) of rifampicin-gelatin grafts against S epidermidis, MRSA, and E coli were 40.0 ± 0.3 mm, 36.0 ± 0.2 mm, and 11.8 ± 0.1 mm, respectively. In the implantation, S epidermidis -inoculated rifampicin-gelatin grafts had no findings of graft infection, and no colony growth was recognized on the plates streaked with the perigraft fluids. Initial inhibition zones of S epidermidis -inoculated rifampicin-gelatin grafts retrieved at 1 or 2 weeks were 20.1 ± 1.1 mm and 7.6 ± 1.0 mm, respectively. In E coli -inoculated and MRSA-inoculated rifampicin-gelatin grafts, all of the eight animals had perigraft abscess, and blood culture test results probed septicemia in five animals with patent grafts at death. Inhibition zones against E coli or MRSA were not formed on the plates streaked with the same organism, whereas initial inhibition zones of E coli -inoculated and MRSA-inoculated rifampicin-gelatin grafts on S epidermidis -streaked plates were 8.0 ± 0.2 mm and 18.5 ± 0.5 mm, respectively. In the MRSA group, however, recolonization of high minimal inhibitary concentration strains developed within the inhibition zones as early as 24 hours. Histologically, neither organisms nor inflammatory cells were found in S epidermidis -inoculated rifampicin-gelatin grafts and tissue ingrowth was recognized at 2 to 4 weeks, whereas E coli -inoculated and MRSA-inoculated rifampicin-gelatin grafts had aggressive neutrophil infiltration into the graft interstices, revealing establishment of uncontrollable graft infection. Conclusion: These results suggested that rifampicin-gelatin grafts are clearly valid for S epidermidis infection, whereas no efficacy was recognized against either MRSA or E coli graft infection because of early development of high minimal inhibitary concentration MRSA strains or poor susceptibility. (J Vasc Surg 2002;35:779-85.

Training with Hybrid Assistive Limb for walking function after total knee arthroplasty

BackgroundThe Hybrid Assistive Limb (HAL, CYBERDYNE) is a wearable robot that provides assistance to patients while walking, standing, and performing leg movements based on the intended movement of the wearer. We aimed to assess the effect of HAL training on the walking ability, range of motion (ROM), and muscle strength of patients after total knee arthroplasty (TKA) for osteoarthritis and rheumatoid arthritis, and to compare the functional status after HAL training to the conventional training methods after surgery.MethodsNine patients (10 knees) underwent HAL training (mean age 74.1 ± 5.7 years; height 150.4 ± 6.5 cm; weight 61.2 ± 8.9 kg), whereas 10 patients (11 knees) underwent conventional rehabilitation (mean age 78.4 ± 8.0 years; height 150.5 ± 10.0 cm; weight 59.1 ± 9.8 kg). Patients underwent HAL training during 10 to 12 (average 14.4 min a session) sessions over a 4-week period, 1 week after TKA. There was no significant difference in the total physical therapy time including HAL training between the HAL and control groups. Gait speed, step length, ROM, and muscle strength were evaluated.ResultsThe nine patients completed the HAL training sessions without adverse events. The walking speed and step length in the self-selected walking speed condition, and the walking speed in the maximum walking speed condition were greater in the HAL group than in the control group at 4 and 8 weeks (P < 0.05). The step length in the maximum walking speed condition was greater in the HAL group than in the control group at 2, 4, and 8 weeks (P < 0.05). The extension lag and knee pain were lower in the HAL group than in the control group at 2 weeks (P < 0.05). The muscle strength of knee extension in the HAL group was greater than that in the control group at 8 weeks (P < 0.05).ConclusionHAL training after TKA can improve the walking ability, ROM, and muscle strength compared to conventional physical therapy for up to 8 weeks after TKA. Since the recovery of walking ability was earlier in the HAL group than in the control group and adverse events were not observed in this pilot study, HAL training after TKA can be considered a safe and effective rehabilitation intervention

High accumulation of plasminogen and tissue plasminogen activator at the flow surface of mural fibrin in the human arterial system

AbstractPurpose: We assessed the fibrinolytic activity of the organized mural thrombus lining of aneurysms and prosthetic grafts. Methods: Between May 1995 and April 1998, the full-thickness mural thrombi of aneurysms and the pseudointima lining of vascular grafts were obtained from 12 patients, ranging from 55 to 78 years in age, who underwent elective surgery. These included five aortic arch aneurysms, four abdominal aortic aneurysms, and three patent synthetic vascular grafts. The specimens were subjected to sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE)/immunoblot and immunohistochemistry for human plasmin/plasminogen, tissue plasminogen activator (tPA), and fibrin degradation product (D-dimer). Results: In the SDS-PAGE/immunoblot, 25- and 27-kd bands appeared specifically in experimental fibrin plates after limited digestion by plasmin and were also recognized in the mural thrombi. The presence of bands at 25 and 27 kd, which were most prominent in sections near the flow surface layer, was consistent with the hypothesis that the mural fibrin was digested by the endogenous plasmin. Apparent immunoreactivity was found at the flow surface of the masses at a thickness of 10 to 400 μm, suggesting the presence of a plasminogen and tPA-rich layer, with D-dimer as a consequential product of fibrinolysis. Conclusion: The hypothesis that fibrin surfaces in the arterial system acquire fibrinolytic activity because of digestion by circulating endogenous plasmin was confirmed; this may contribute to the antithrombogenicity of these flow surfaces. (J Vasc Surg 2000;32:374-82.