• Toxicological Research
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• v.28 no.1
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• pp.19-24
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• 2012

In the present study, toxicity of silver nanoparticles (AgNPs) was investigated in the nematode, Caenohabditis elegans focusing on the upstream signaling pathway responsible for regulating oxidative stress, such as mitogen-activated protein kinase (MAPK) cascades. Formation of reactive oxygen species (ROS) was observed in AgNPs exposed C.elegans, suggesting oxidative stress as an important mechanism in the toxicity of AgNPs towards C. elegans. Expression of genes in MAPK signaling pathways increased by AgNPs exposure in less than 2-fold compared to the control in wildtype C.elegans, however, those were increased dramatically in sod-3 (gk235) mutant after 48 h exposure of AgNPs (i.e. 4-fold for jnk-1 and mpk-2; 6-fold for nsy-1, sek-1, and pmk-1, and 10-fold for jkk-1). These results on the expression of oxidative stress response genes suggest that sod-3 gene expression appears to be dependent on p38 MAPK activation. The high expressions of the pmk-1 gene 48 h exposure to AgNPs in the sod-3 (gk235) mutant can also be interpreted as compensatory mechanisms in the absence of important stress response genes. Overall results suggest that MAPK-based integrated stress signaling network seems to be involved in defense to AgNPs exposure in C.elegans.

• Journal of Chest Surgery
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• v.43 no.5
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• pp.542-545
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• 2010

Extramedullary hematopoiesis is a common compensatory mechanism of chronic anemia, but an asymptomatic posterior mediastinal mass is rarely diagnosed as an extramedullary hematopoiesis after surgical resection. The differential from neurogenic tumors is important, but fine needle aspiration biopsy is not recommended because of the difficulty of approach and risk of bleeding. Although diagnosis and treatment can involve resection via thoracotomy, video-assisted thoracic surgery may also be a useful strategy. We performed video-assisted thoracic surgery on a 59-year-old man for posterior mediastinal extramedullary hematopoiesis, with no evidence of recurrence or related hematologic diseases.

• The Korean Journal of Pharmacology
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• v.2 no.1 s.2
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• pp.99-109
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• 1966

It has been known that the pronounced hypotension resulting from hemorrhage gives rise to compensatory stimulation of the adrenosympathetic system, which leads to an increase of liberation of catecholamines from sympathetic nervous system and adrenal medulla. It is obvious, therefore, that numerous physiological and biochemical changes during the hemorrhagic hypotention might be mediated through the increased liberation of catecholamines. Although an extensive studies have been reported on changes of protein and carbohydrate metabolism in hemorrhagic shock a few studies on the changes of lipid metabolism have been reported. Levenson(1961) observed a marked increase of serum lipids content during hemorrhagic shock and also noticed a marked elevation of serum free fatty acids. He suggested that these effects were due to mobilization and accelerated metabolic breakdown of lipids which might be resulted by sympathetic stimulation as a cause. To elucidate the mechanism of this, author studied the change of serum free fatty acids and blood sugar with relation to catecholamines during experimentally induced hemorrhagic shock in dog. Healthy male mongrel dogs weighing approximately 15kg were used. Under the general anesthesia with pentobarbital, rapid hemorrhage was produced from the femoral artery maintaining blood pressure level of 40 mmHg measured by the manometer connected with the opposite femoral artery throughout the experiment. Serum free fatty acids(FFA) and blood sugar were measured by the methods of Dole(1956) and Folin-wu,(1920) respectively. Tissue catecholamine was measured by Shore and Olin method(1958) using Aminco-Bowman spectrophotofluorometer.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.7 no.1
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• pp.27-31
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• 1996

The voice of aged persons is known generally to be somewhat different from that of other adults, suggesting that laryngeal change occurs with advancing age. However, because knowledge of the voice characteristics of aged persons is limited, it is difficult to judge whether their voices arc normal. Chart review and laryngoscopic examination from ninety-one patients with hoarseness over the age of 60(1st group) and one hundred sixteen patients with hoarseness below the age of 50(2nd group) were done to define aging related voice disorders. The following results were obtained. 1) Associated diseases related to laryngeal disease were hypertension(12%), pulmonary disease(4.4%), thyroid disease(1.1%) in 1st group and hypertension(9.5%), thyroid disease(1.7%) in 2nd group. 2) The underlying diseases causing hoarseness in order of frequency were benign vocal fold lesion(37.7%), inflammatory disease(36.8%), functional dysphonia(17%) in 1st group and benign vocal fold lesion(43.6%), functional dysphonia(26.3%), inflammatory disease(16.5%) in 2nd group. 3) In stroboscopic findings, atrophy and sulcus of vocal cords are more prevalent in males than in females and edema of vocal cords is more common in females. Generally the voice characteristics of aged persons depend on the mass of the vocal folds which may be decreased through atrophy or be increased by edema. However, other factors such as systemic diseases, drug side effects and compensatory mechanism to presbylaryngis must be taken into account in diagnosing and treating voice disorders in aged persons.

• The Korean Journal of Physiology
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• v.30 no.2
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• pp.237-247
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• 1996

This study was carried out to determine the effect of $-6^{\circ}$ head-down bedrest on the cardiovascular and hormonal responses to orthostasis and to evaluate the mechanism of orthostatic intolerance. Ten healthy young men were changed the body position from $-6^{\circ}$ head-down or supine bedrest for 2 hr to $70^{\circ}$ head-up tilt for 20 min. During the bedrest, there were no differences in hemodynamic and hormonal changes between the head-down and the supine positions. However, the tendency of decreased end-diastolic volume and increased cardiac contractility during the later period of 2 hr showed that the cardiovascular adaptation could be accelerated within a relatively short period in the head-down bedrest. During the head-up tilt, presyncopal signs were developed in five subjects of the supine bedrest, and one of the same subjects of the head-down bedrest. In the tolerant subjects, the increase in cardiac contractility and plasma epinephrine level during the bend-up tilt was greater following the head-down bedrest than that following the supine bedrest to compensate for reduced venous return. The intolerant subjects showed the greater decrease in end-diastolic and stroke volume, and the greater increase in heart rate during the head-up tilt than the tolerant subjects. Cardiac contractility and plasma epinephrine level were remarkably increased. However, arterial pressure was not maintained at the level for the appropriate compensation of the reduced venous return. It seems that the tolerance to orthostasis is more effective after the short-term head-down bedrest than after the supine bedrest, and the secretion of epinephrine induces the higher cardiac performance as a compensatory mechanism fur the reduced venous return during the orthostasis following the head-down bedrest than the supine bedrest.

• Journal of Microbiology and Biotechnology
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• v.34 no.6
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• pp.1214-1221
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• 2024

The accumulating evidence substantiates the indispensable role of gut microbiota in modulating the pathogenesis of type 2 diabetes. Uncovering the intricacies of the mechanism is imperative in aiding disease control efforts. Revealing key bacterial species, their metabolites and/or metabolic pathways from the vast array of gut microorganisms can significantly contribute to precise treatment of the disease. With a high prevalence of type 2 diabetes in Inner Mongolia, China, we recruited volunteers from among the Mongolian population to investigate the relationship between gut microbiota and the disease. Fecal samples were collected from the Volunteers of Mongolia with Type 2 Diabetes group and a Control group, and detected by metagenomic analysis and untargeted metabolomics analysis. The findings suggest that Firmicutes and Bacteroidetes phyla are the predominant gut microorganisms that exert significant influence on the pathogenesis of type 2 diabetes in the Mongolian population. In the disease group, despite an increase in the quantity of most gut microbial metabolic enzymes, there was a concomitant weakening of gut metabolic function, suggesting that the gut microbiota may be in a compensatory state during the disease stage. β-Tocotrienol may serve as a pivotal gut metabolite produced by gut microorganisms and a potential biomarker for type 2 diabetes. The metabolic biosynthesis pathways of ubiquinone and other terpenoid quinones could be the crucial mechanism through which the gut microbiota regulates type 2 diabetes. Additionally, certain Clostridium gut species may play a pivotal role in the progression of the disease.

• Journal of Korean Orthopaedic Sports Medicine
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• v.3 no.1
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• pp.66-72
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• 2004

Purpose: To evaluate the compensatory mechanism in vivo and develop the treatment guide by performing the comprehensive functional tests of the posterior cruciate ligament (PCL) deficient subjects. Material and Methods: 10 PCL deficient subjects and 10 healthy control group were evaluated. Performed functional tests were range of motion, posterior drawer test, Telos, 30$^{\circ}$ flexion wt-bearing view, KT-1000 arthrometer, gait analysis, EMG test and isokinetic tests. Results: Physical, KT-1000, Telos posterior tests showed significant differences, but 300 full weight bearing lateral view, muscle strength test revealed no difference between two groups. Less knee flexion at initial contact and reduced maximum valgus moment were observed in PCL deficient group. In vertical drop landing, PCL group had increased plantar flexion angle at initial contact. Conclusion: Compensatory mechanisms such as reduced unstable components and absorbing the maximal load of the joint were occurred after PCL insufficiency, which result in good clinical and functional outcomes. Further investigations would be needed to understand the functional adaptations of PCL deficient subjects.

• BMB Reports
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• v.37 no.4
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• pp.454-459
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• 2004

Experimental hyperoxia represents a suitable in vitro model to study some pathogenic mechanisms related to oxidative stress. Moreover, it allows the investigation of the molecular pathophysiology underlying oxygen therapy and toxicity. In this study, a modified experimental set up was adopted to accomplish a model of moderate hyperoxia (50% $O_2$, 96 h culture) to induce oxidative stress in the human leukemia cell line, U-937. Spectrophotometric measurements of mitochondrial respiratory enzyme activities, NMR spectroscopy of culture media, determination of antioxidant enzyme activities, and cell proliferation and differentiation assays were performed. The data showed that moderate hyperoxia in this myeloid cell line causes: i) intriguing alterations in the mitochondrial activities at the levels of succinate dehydrogenase and succinate-cytochrome c reductase; ii) induction of metabolic compensatory adaptations, with significant shift to glycolysis; iii) induction of different antioxidant enzyme activities; iv) significant cell growth inhibition and v) no significant apoptosis. This work will permit better characterization the mitochondrial damage induced by hyperoxia. In particular, the data showed a large increase in the succinate cytochrome c reductase activity, which could be a fundamental pathogenic mechanism at the basis of oxygen toxicity.

• Reproductive and Developmental Biology
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• v.33 no.3
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• pp.163-169
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• 2009

Many biological systems are regulated by an intricate set of feedback loops that oscillate with a circadian rhythm of roughly 24 h. This circadian clock mediates an increase in body temperature, heart rate, blood pressure, and cortisol secretion early in the day. Recent studies have shown changes in the amplitude of the circadian clock in the hearts and livers of streptozotocin (STZ)-treated rats. It is therefore important to examine the relationships between circadian clock genes and growth factors and their effects on diabetic phenomena in animal models as well as in human patients. In this study, we sought to determine whether diurnal variation in organ development and the regulation of metabolism, including growth and development during the juvenile period in rats, exists as a mechanism for anticipating and responding to the environment. Also, we examined the relationship between changes in growth factor expression in the liver and clock-controlled protein synthesis and turnover, which are important in cellular growth. Specifically, we assessed the expression patterns of several clock genes, including Per1, Per2, Clock, Bmal1, Cry1 and Cry2 and growth factors such as insulin-like growth factor (IGF)-1 and -2 and transforming growth factor (TGF)-${\beta}1$ in rats with STZ-induced diabetes. Growth factor and clock gene expression in the liver at 1 week post-induction was clearly increased compared to the level in control rats. In contrast, the expression patterns of the genes were similar to those observed after 5 weeks in the STZ-treated rats. The increase in gene expression is likely a compensatory change in response to the obstruction of insulin function during the initial phase of induction. However, as the period of induction was extended, the expression of the compensatory genes decreased to the control level. This is likely the result of decreased insulin secretion due to the destruction of beta cells in the pancreas by STZ.

• Journal of The Korean Society of Integrative Medicine
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• v.1 no.1
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• pp.61-68
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• 2013

Purpose : The purpose of this study is to evaluate the stability and balance of the body, mobility complex exercise group and a student group for FMS tests to compare the differences between the two groups to identify its purpose. Method : The subjects of this study FMS measuring D University Physical Therapy, a student enrolled patients (7:7), and 7 patients total of 14 patients was conducted, compound exercise group weekly stretching 10 minutes, the 24 members who have run a complex exercise, 10 minutes of cool down stretching, 20-minute aerobic exercise were included in the study. Result : The results of this study, according to 1) Deep squat, Inline lunge, Trunk Stability Push-up there was significant difference(p<0.05), compound exercise group came out significantly higher. 2) Hurdle Step, Shoulder Mobility Reaching, Active Straight-leg Raise, Rotary stability in measured target these women flexibility because the test items that did not show a significant difference(p>0.05), the two groups averaged compared to the other items were higher. Complex exercise group, a statistically significant difference was overall average. Conclusion : FMS can not be resolved because of a compensatory mechanism to identify disparities and unbalanced movement patterns can help. Therefore, if the FMS and other tests conducted by splicing, will be utilized more profitably, and you will be able to suggest ways that can have a positive impact injury prevention is added to the side to expand the scope of the physical therapist.