RESUMO
Mitochondrial DNA (mtDNA) is a genome possessed by mitochondria. Since reactive oxygen species (ROS) are generated during aerobic respiration in mitochondria, mtDNA is commonly exposed to the risk of DNA damage. Mitochondrial disease is caused by mitochondrial dysfunction, and mutations or deletions on mitochondrial tRNA (mt tRNA) genes are often observed in mtDNA of patients with the disease. Hence, the correlation between mt tRNA activity and mitochondrial dysfunction has been assessed. Then, cybrid cells, which are constructed by the fusion of an enucleated cell harboring altered mtDNA with a ρ(0) cell, have long been used for the analysis due to difficulty in mtDNA manipulation. Here, we propose a new method that involves mt tRNA cleavage by a bacterial tRNA-specific ribonuclease. The ribonuclease tagged with a mitochondrial-targeting sequence (MTS) was successfully translocated to the mitochondrial matrix. Additionally, mt tRNA cleavage, which resulted in the decrease of cytochrome c oxidase (COX) activity, was observed.
Assuntos
Proteínas de Escherichia coli/metabolismo , RNA de Transferência/metabolismo , RNA/metabolismo , Sequência de Bases , DNA Mitocondrial/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Células HeLa , Humanos , Mitocôndrias/genética , Mitocôndrias/metabolismo , Doenças Mitocondriais/genética , Dados de Sequência Molecular , RNA/genética , RNA Mitocondrial , RNA de Transferência/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismoRESUMO
Background: Giant malignant tumors have an increased risk of intraoperative rupture, which might lead to a worse disease condition and tumor recurrence. We performed a clinical study on patients with a giant ovarian mass who underwent laparoscopy combined with an Aron Alpha method. Methods: This retrospective clinical study spanned from January 2016 to September 2022 and included 23 patients with giant ovarian tumors treated with an Aron Alpha method. Results: The mean age of the subjects was 47.6 ± 17.8 years, mean tumor diameter 20.4 ± 5.8 cm, mean surgical duration 87.2 ± 33.1 min, and mean hemorrhage volume 94.1 ± 92.2 mL. No patient experienced intraoperative tumor rupture or surgery-related symptoms. Histopathology of excised samples revealed serous cyst adenoma and mucinous cystadenoma, mucinous cystadenoma of borderline malignancy and mature cystic teratoma, and endometriotic cyst adenoma in 6, 4, and 3 patients, respectively. The mean hospitalization period was 6.0 ± 1.2 days, and the hospitalization period was not extended in any subject. Conclusion: The Aron Alpha method allows tumor resection without capsular rupture and is a useful, minimally invasive surgical method for resecting giant ovarian tumors in which malignancy cannot be ruled out.
RESUMO
Multiple sensors and actuators integrated in a small space, especially an elongated thin structure, require equivalent number of signal lines between microdevices, but there is limited space for signal wires. Thus, we propose a mechanism using a single microchannel where a liquid metal droplet moves and shuttles. A shuttling droplet switches multiple terminals of signal lines along a microchannel based on a traditional switching mechanism using a liquid metal droplet. Electrically conductive gallium alloy liquid metals (Galinstan) can flow in a microchannel due to their fluidity. The terminals consist of opposing electrode pairs in a microchannel. A change in a variable impedance connected to a terminal as a pseudo sensor can be read when a droplet flows in and connects electrode pairs. This paper presents switching and addressing objective terminals of chromium electrodes by a shuttling conductive droplet (500 µm in diameter and 10 mm long) in a microchannel (500 µm in diameter and 100 mm long). A demonstrated simple mechanism enables communication between multiple microdevices along a microchannel. We anticipate wide application of proposed mechanism toward a multiplexer, especially in microfluidic devices because of the advantages of utilizing microchannels as common microstructures for both microdevices and signal lines.
RESUMO
Human-robot interaction technology has contributed to improving sociality for humanoid robots. At scales far from human scales, a microrobot can interact with an environment in a small world. Microsensors have been applied to measurement of forces by flying or walking insects. Meanwhile, most previous works focused on the measurement of the behavior of insects. Here, we propose microrobot-insect interactions by soft microfingers integrated with artificial muscle actuators and tactile sensors, which has been developed for a haptic teleoperation robot system. A soft pneumatic balloon actuator acts as the artificial muscle, and a flexible strain sensor using a liquid metal provides tactile sensing. Force interaction between a pill bug and the microfinger could be accomplished. The microfinger (12 mm × 3 mm × 490 µm) can move and touch an insect, and it can detect reaction force from an insect. The measured reaction force from the legs of a pill bug as a representative insect was less than 10 mN. This paper presents a microfinger as an end effector for the active sensing of reaction force from a small insect. We anticipate that our results will lead to further evaluation of small living things as well as technology development for human-environment interaction.
Assuntos
Robótica , Percepção do Tato , Animais , Humanos , Insetos , Fenômenos Mecânicos , TatoRESUMO
BACKGROUND: Hypermenorrhea is characterized by excessive menstrual bleeding that causes severe anemia and interferes with everyday life. This condition can restrict women's social activities and decrease their quality of life. Microwave endometrial ablation (MEA) using a 2.45-GHz energy source is a minimally invasive alternative to conventional hysterectomy for treating hypermenorrhea that is resistant to conservative treatment, triggered by systemic disease or medications, or caused by uterine myomas and fibrosis. The popularity of MEA has increased worldwide. Although MEA can safely and effectively treat submucous myomas, some patients may still experience recurrent hypermenorrhea postoperatively and may require additional treatment. AIM: To investigate the efficacy of MEA combined with transcervical resection (TCR). METHODS: Participants underwent cervical and endometrial evaluations. Magnetic resonance imaging and hysteroscopy were performed to evaluate the size and location of the myomas. TCR was performed before MEA using a hystero-resectoscope. MEA was performed using transabdominal ultrasound. The variables included operation time, number of ablation cycles, length of hospital stay, and visual analog scale cores for hypermenorrhea, dysmenorrhea, and treatment satisfaction at 3 and 6 mo postoperatively. The postoperative incidence of amenorrhea, changes in hemoglobin concentrations, and MEA-related complications were evaluated. RESULTS: A total of 34 women underwent a combination of MEA and TCR during the study period. Two patients were excluded from the study as their histopathological tests identified uterine malignancies (uterine sarcoma and endometrial cancer). The 32 eligible women (6 nulliparous, 26 multiparous) had a mean age of 45.2 ± 4.3 years (range: 36-52 years). Patients reported very severe hypermenorrhea (10/10 points on the visual analog scale) before the procedure. However, after the procedure, the hypermenorrhea scores decreased to 1.2 ± 1.3 and 0.9 ± 1.3 at 3 and 6 mo, respectively (P < 0.001). The mean follow-up duration was 33.8 ± 16.8 mo. Although 10 women (31.3%) developed amenorrhea during this period, none experienced a recurrence of hypermenorrhea. No surgical complications were observed. CONCLUSION: Reducing the size of uterine myomas by combining MEA and TCR can safely and effectively treat hypermenorrhea in patients with submucous myomas.
RESUMO
Motion capture of a robot and tactile sensing for a robot require sensors. Strain sensors are used to detect bending deformation of the robot finger and to sense the force from an object. It is important to introduce sensors in effective combination with actuators without affecting the original performance of the robot. We are interested in the improvement of flexible strain sensors integrated into soft microrobot fingers using a pneumatic balloon actuator (PBA). A strain sensor using a microchannel filled with liquid metal was developed for soft PBAs by considering the compatibility of sensors and actuators. Inflatable deformation generated by PBAs, however, was found to affect sensor characteristics. This paper presents structural reinforcement of a liquid metal-based sensor to solve this problem. Parylene C film was deposited into a microchannel to reinforce its structure against the inflatable deformation caused by a PBA. Parylene C deposition into a microchannel suppressed the interference of inflatable deformation. The proposed method enables the effective combination of soft PBAs and a flexible liquid metal strain sensor for use in microrobot fingers.
RESUMO
Brain-derived neurotrophic factor (BDNF), a member of the neurotrophin family, plays an important role in cognitive abilities, including memory and learning. We demonstrated that soybean protein hydrolysate (SPH) diet suppresses age-related cognitive decline via the upregulation of BDNF in a mouse model of senescence. Our purpose was to identify novel bioactive peptides in SPH, which enhance BDNF expression. We treated mouse primary astrocytes with SPH as well as with its positively charged chromatographic fraction. Significant increases in the expression of BDNF were observed in the treatment with positively charged fraction of SPH. Among the synthesized peptides, the dipeptide glycine-arginine (GR) increased BDNF expression in vitro, and LC-TOF-MS analysis showed the presence of GR in the SPH. Furthermore, its administration in vivo increased the expression of BDNF in the cerebral cortex and the number of neurons in hippocampus and cerebral cortex. These data indicate that GR might promote neurogenesis by upregulating BDNF levels.