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S-Adenosylmethionine (SAM) Regulates Antibiotic Biosynthesis in Streptomyces spp. in a Mode Independent of Its Role as a Methyl Donor

  • Zhao Xin-Qing;Jin Ying-Yu;Kwon Hyung-Jin;Yang Young-Yell;Suh Joo-Won
    • Journal of Microbiology and Biotechnology
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    • v.16 no.6
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    • pp.927-932
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    • 2006
  • S-Adenosylmethionine (SAM) is a ubiquitous biomolecule serving mainly as a methyl donor. Our recent studies revealed that SAM controls antibiotic production in Streptomyces. In this study, the functional mode of SAM was studied in S. coelicolor and S. antibioticus ATCC11891, employing S-adenosylhomocysteine (SAH), a methylation reaction product of SAM. Actinorhodin biosynthesis did not require SAM as a methyl donor, whereas SAH enhanced the actinorhodin biosynthesis up to the level comparable to SAM, and the most effective concentration of SAH was higher than that of SAM. In the case of oleandomycin that requires SAM for its biosynthesis, both SAM and SAH at the concentration as low as 100 mM showed comparable efficacy in enhancing the production; SAM at 1 mM concentration additionally stimulated to give a 5-fold enhancement of oleandomycin production. In vitro autophosphorylation of protein kinase AfsK was found to be activated by both SAM and SAH, as well as other structurally related compounds. Our studies demonstrate that SAM regulates antibiotic biosynthesis in a mode independent of its role as a methyl donor and suggest that SAM acts directly as an intracellular signaling molecule for Streptomyces.

Comparative Analysis of Wind Power Energy Potential at Two Coastal Locations in Bangladesh

  • Islam, Asif;Rahman, Mohammad Mahmudur;Islam, Mohammad Shariful;Bhattacharya, Satya Sundar;Kim, Ki-Hyun
    • Asian Journal of Atmospheric Environment
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    • v.9 no.4
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    • pp.288-297
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    • 2015
  • In this study, wind conditions and its energy potential have been assessed by conducting a Weibull analysis of the wind speed data (over the period of 2002-2011) measured from a port city (Mongla) and an isolated island (Sandwip) in Bangladesh. The monthly mean wind speed at Mongla ranged from 1.60 m/s (December) to 2.47 m/s (April). The monthly values of Weibull shape parameter (k) were from 1.27 to 2.53. In addition, the values of the scale parameter (c) and the monthly wind power density ranged from 1.76 to 2.79 m/s and 3.95 to $17.45W/m^2$, respectively. The seasonal mean wind speed data varied from 1.72 (fall) to 2.29 m/s (spring) with the wind power density from 5.33 (fall) to $14.26W/m^2$ (spring). In the case of Sandwip, the results were comparable to those of Mongla, but moderate reductions in all the comparable variables were observed. The wind data results of these two areas have been compared with those of eight other locations in the world with respect to wind power generation scale. According to this comparison, the wind power generation scale for Mongla and Sandwip was adequate for stand-alone small/micro-scale applications such as local household consumption, solar-wind hybrid irrigation pumps, and battery charging.

Comparison of Reaction Times of Ankle Joint Muscles in the Elderly Men and Women (고령자 남녀의 발목관절 근육 반응시간의 비교)

  • Kim, Ji-Won;Jeong, Hong-Young;Kim, Hyo-Hee;Kwon, Yu-Ri;Eom, Gwang-Moon;Lee, Jeong-Whan;Kim, Kyung-Seoup;Jun, Jae-Hoon;Park, Byung Kyu
    • Journal of Biomedical Engineering Research
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    • v.33 no.4
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    • pp.163-168
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    • 2012
  • Elderly women are reported to have greater risk of falls. The purpose of this paper was to investigate the possible gender differences in the reaction performance of ankle joint muscles, which have dominant role in the control of sagittal plane balance. Twenty-six elderly men and women with comparable mean age participated in this study. Reaction times to the audible beeps were measured in the tibialis anterior muscle and gastrocnemius muscle. Reaction time variables included premotor time, electromechanical delay and total reaction time. Gender difference in each reaction time was investigated by independent t-test. In both muscles, premotor time was longer in men but the electromechanical delay was longer in women (p < 0.05). Resulting total reaction time was longer in men in tibialis anterior muscle (p < 0.01) and it tended to be longer in men also in gastrocnemius muscle (p = 0.25). The results demonstrates that the overall reaction performances of elderly women is better than or comparable to those of elderly men in ankle joint muscles. This suggests that the reaction performance of ankle muscles is hardly the cause of the greater risk of falls in elderly women.

CELLULAR ATTACHMENT AND GENE EXPRESSION OF OSTEOBLAST-LIKE CELLS ON ZIRCONIA CERAMIC SURFACES

  • Pae, Ah-Ran;Lee, Hee-Su;Kim, Hyeong-Seob; Baik, Jin;Woo, Yi-Hyung
    • The Journal of Korean Academy of Prosthodontics
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    • v.46 no.3
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    • pp.227-237
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    • 2008
  • STATEMENT OF PROBLEM: Zirconium oxide can be a substitute to titanium as implant materials to solve the esthetic problems of dark color in the gingival portion of implant restorations. PURPOSE: This study was performed to define attachment and growth behavior of osteoblast- like cells cultured on grooved surfaces of zirconium oxide and evaluate the genetic effect of zirconium oxide surfaces using the reverse transcriptase-polymerase chain reaction (RT-PCR). MATERIAL AND METHODS: MC3T3-E1 cells were cultured on (1) commercially pure titanium discs with smooth surface (T group), (2) yttrium-stabilized tetragonal zirconia polycrystal (Y-TZP) with machined surface (ZS group), and (3) Y-TZP with $100{\mu}m$ grooves (ZG group). Cell proliferation activity was evaluated through MTT assay and cell morphology was examined by SEM. The mRNA expression of Runx2, alkaline phosphatase, osteocalcin, TGF-${\beta}1$, IGF-1, G3PDH in E1 cells were evaluated by RT-PCR. RESULTS: From the MTT assay, after 48 hours of adhesion of MC3T3-E1 cells, the mean optical density value of T group and ZG group significantly increased compared to the ZS group. SEM images of osteoblast-like cells showed that significantly more cells were observed to attach to the grooves and appeared to follow the direction of the grooves. After 24 hours of cell adhesion, more spreading and flattening of cells with active filopodia formation occurred. Results of RT-PCR suggest that T group, ZS group, and ZG group showed comparable osteoblast-specific gene expression after 24 hours of cell incubation. CONCLUSION: Surface topography and material of implants can play an important role in expression of osteoblast phenotype markers. Zirconia ceramic showed comparable biological responses of osteoblast-like cells with titanium during a short-time cell culture period. Also, grooves influence cell spreading and guide the cells to be aligned within surface grooves.

Systematic Review and Comparative Meta-Analysis of Outcomes Following Pedicled Muscle versus Fasciocutaneous Flap Coverage for Complex Periprosthetic Wounds in Patients with Total Knee Arthroplasty

  • Economides, James M.;DeFazio, Michael V.;Golshani, Kayvon;Cinque, Mark;Anghel, Ersilia L.;Attinger, Christopher E.;Evans, Karen Kim
    • Archives of Plastic Surgery
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    • v.44 no.2
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    • pp.124-135
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    • 2017
  • Background In cases of total knee arthroplasty (TKA) threatened by potential hardware exposure, flap-based reconstruction is indicated to provide durable coverage. Historically, muscle flaps were favored as they provide vascular tissue to an infected wound bed. However, data comparing the performance of muscle versus fasciocutaneous flaps are limited and reflect a lack of consensus regarding the optimal management of these wounds. The aim of this study was to compare the outcomes of muscle versus fasciocutaneous flaps following the salvage of compromised TKA. Methods A systematic search and meta-analysis were performed to identify patients with TKA who underwent either pedicled muscle or fasciocutaneous flap coverage of periprosthetic knee defects. Studies evaluating implant/limb salvage rates, ambulatory function, complications, and donor-site morbidity were included in the comparative analysis. Results A total of 18 articles, corresponding to 172 flaps (119 muscle flaps and 53 fasciocutaneous flaps) were reviewed. Rates of implant salvage (88.8% vs. 90.1%, P=0.05) and limb salvage (89.8% vs. 100%, P=0.14) were comparable in each cohort. While overall complication rates were similar (47.3% vs. 44%, P=0.78), the rates of persistent infection (16.4% vs. 0%, P=0.14) and recurrent infection (9.1% vs. 4%, P=0.94) tended to be higher in the muscle flap cohort. Notably, functional outcomes and ambulation rates were sparingly reported. Conclusions Rates of limb and prosthetic salvage were comparable following muscle or fasciocutaneous flap coverage of compromised TKA. The functional morbidity associated with muscle flap harvest, however, may support the use of fasciocutaneous flaps for coverage of these defects, particularly in young patients and/or high-performance athletes.

Dechlorination of High Concentrations of Tetrachloroethylene Using a Fixed-bed Reactor

  • Chang, Young-C.;Park, Chan-Koo;Jung, Kweon;Kikuchi, Shintaro
    • Journal of Environmental Health Sciences
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    • v.36 no.4
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    • pp.323-336
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    • 2010
  • We evaluated the properties of a fixed-bed column reactor for high-concentration tetrachloroethylene (PCE) removal. The anaerobic bacterium Clostridium bifermentans DPH-1 was able to dechlorinate PCE to cis-1,2-dichloroethylene (cDCE) via trichloroethylene (TCE) at high rates in the monoculture biofilm of an upflow fixed-bed column reactor. The first-order reaction rate of C. bifermentans DPH-1 was relatively high at $0.006\;mg\;protein^{-1}{\cdot}l{\cdot}h^{-1}$, and comparable to rates obtained by others. When we gradually raised the influent PCE concentration from $30\;{\mu}M$ to $905\;{\mu}M$, the degree of PCE dechlorination rose to over 99% during the operation period of 2,000 h. In order to maintain efficiency of transformation of PCE in this reactor system, more than 6 h hydraulic retention time (HRT) is required. The maximum volumetric dechlorination rate of PCE was determined to be $1,100\;{\mu}mol{\cdot}d^{-1}l$ of reactor $volume^{-1}$, which is relatively high compared to rates reported previously. The results of this study indicate that the PCE removal performance of this fixed-bed reactor immobilized mono-culture is comparable to that of a fixed-bed reactor mixture culture system. Furthermore, our system has the major advantage of a rapid (5 days) start-up time for the reactor. The flow characteristics of this reactor are intermediate between those of the plug-flow and complete-mix systems. Biotransformation of PCE into innocuous compounds is desirable; however, unfortunately cDCE, which is itself toxic, was the main product of PCE dechlorination in this reactor system. In order to establish a system for complete detoxification of PCE, co-immobilization of C. bifermentans DPH-1 with other bacteria that degrade cDCE aerobically or anaerobically to ethene or ethane may be effective.

Effect of Partial Replacement of Dietary Protein by a Leaf Meal Mixture Containing Leucaena leucocephala, Morus alba and Azadirachta indica on Performance of Goats

  • Patra, A.K.;Sharma, K.;Dutta, Narayan;Pattanaik, A.K.
    • Asian-Australasian Journal of Animal Sciences
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    • v.15 no.12
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    • pp.1732-1737
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    • 2002
  • This study was conducted to examine the effect of Leucaena leucocephala-Morus alba-Azadirachta indica (2:1:1) based leaf meal mixture as nitrogen source to partially replace (50%) soybean meal in conventional supplements on the performance of goats. Twelve non-descript female goats were divided into two equal groups in a completely randomized design to receive either the leaf meal mixture based supplement (LMAM) or soybean meal incorporated concentrate (SBM) and wheat straw for ad libitum intake for a two month period. The goats given LMAM and SBM concentrate had similar dry matter intake ($50.2{\pm}1.67g/kg\;W^{0.75}$) and nutrient digestibility. Nitrogen intake and its faecal and urinary excretion were similar irrespective of diets. The balance of nitrogen was positive and comparable ($1.63{\pm}0.08g/d$) in both dietary treatments. The plane of nutrition on both diets was comparable and the digestible crude protein and total digestible nutrients values of the composite diets offered did not differ significantly between the dietary supplements. The serum concentration of enzymes alanine aminotransferase and aspartate aminotransferase were statistically similar in both the groups, while haemoglobin and serum urea levels were significantly (p<0.05) higher in LMAM and SBM treatments, respectively. It was concluded that the leaf meal mixture of Leucaena leucocephala-Morus alba-Azadirachta indica could be used as a vegetable protein supplement to wheat straw based diet of goats.

Features of Malignancy Prevalence among Children in the Aral Sea Region

  • Mamyrbayev, Arstan;Dyussembayeva, Nailya;Ibrayeva, Lyazzat;Satenova, Zhanna;Tulyayeva, Anara;Kireyeva, Nurgul;Zholmukhamedova, Dinara;Rybalkina, Dina;Yeleuov, Galymzhan;Yeleuov, Almasbek
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.12
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    • pp.5217-5221
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    • 2016
  • Objective: A study of primary cancer morbidity among children and subsequent calculation of average annual incidence were carried out for boys and girls, and young men and women in Kazakhstan. Methods: The investigated population lived in three areas of the Aral Sea region: designated catastrophe (Aral, Kazalt, Shalkar regions), crisis (Zhalagash, Karmakshy, Shiely regions), pre-crisis (Irgiz, Arys, Ulytau regions). Zhanaarka region of Karaganda oblast was applied as a control. Parameters were retrospective analyzed for the 10 years from 2004 to 2013. Result: The results indicate that indices of children cancer morbidity were slightly higher in the Aral Sea region than in the control district, but they were comparable with similar data from studies in other regions. In all areas of the Aral Sea region, except for Ulytau, primary cancer morbidity exceeded the control level by 1.3-2.7 times (4.7%000). Hematological malignancies, including solid tumors - tumors of musculoskeletal system and skin, digestive system, brain and central nervous system predominated. Stress levels in zones of the Aral Sea region were slightly higher in the crisis zone than in the catastrophe zone that can be explained by the phenomenon of wave-like dynamics of disease growth risk. Gender differences in characteristics of malignancy formation were not more pronounced in the studied region. Conclusion: Indices of children cancer are slightly higher in the Aral Sea region than in the control area of Kazakhstan, but they are comparable to results for other regions.

The value of prophylactic cranial irradiation in limited-stage small cell lung cancer: should it always be recommended?

  • Koh, Minji;Song, Si Yeol;Jo, Ji Hwan;Park, Geumju;Park, Jae Won;Kim, Su Ssan;Choi, Eun Kyung
    • Radiation Oncology Journal
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    • v.37 no.3
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    • pp.156-165
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    • 2019
  • Purpose: Prophylactic cranial irradiation (PCI) is a standard treatment for limited-stage small cell lung cancer (LS-SCLC) showing a response to initial treatment, but many patients do not receive PCI due to comorbidities or refusal. This study aims to define the patient group for whom PCI can be omitted with minimal risk. Materials and Methods: Patients with LS-SCLC who underwent radiotherapy with curative aim at our institution between January 2004 and December 2015 were retrospectively reviewed. Patients who did not receive PCI were evaluated for brain metastasis-free survival (BMFS), progression-free survival (PFS), overall survival (OS), and prognostic factors for survival, and treatment outcomes were compared with a patient cohort who received PCI. Results: A total of 350 patients achieved a response following thoracic radiotherapy, and 190 of these patients did not receive PCI. Stage I-II and a complete response (CR) to initial therapy were good prognostic factors for BMFS and OS on univariate analysis. Patients with both stage I-II and a CR who declined PCI showed comparable 2-year BMFS to those who received PCI (92% vs. 89%). In patients who achieved CR, PCI did not significantly improve OS or PFS. Conclusion: There should be less concern about omitting PCI in patients with comorbidities if they have stage I-II or a CR, with brain metastasis control being comparable to those patients who receive PCI.

Serum Liver Enzyme Pattern in Birth Asphyxia Associated Liver Injury

  • Chhavi, Nanda;Zutshi, Kiran;Singh, Niranjan Kumar;Awasthi, Ashish;Goel, Amit
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.17 no.3
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    • pp.162-169
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    • 2014
  • Purpose: To study temporal pattern of serum liver enzymes levels in newborns with hepatic injury associated with birth asphyxia (BA). Methods: Singleton term newborns with BA and ${\leq}72$ hours of age admitted to neonatal intensive care unit were prospectively enrolled. Term newborns with physiological jaundice and without BA were studied as controls. Serum liver enzymes were measured at <24 hours, 24-72 hours, and at 6-12 days of age for cases and at 1-6 days of age for controls. BA was defined by 1 minute Apgar score <7 or delayed or absent cry with hypoxic ischemic encephalopathy. BA-associated liver injury was defined as serum alanine aminotransferase (ALT) elevation beyond +2 standard deviation (ALT > +2 SD) above the mean of control subjects at any of the three time points. Results: Sixty controls and 62 cases were enrolled. Thirty-five cases (56%) developed BA-associated liver injury (ALT>81 IU/L). They had higher serum levels of ALT, aspartate aminotransferase, lactate dehydrogenase than the control infants, with peak at 24-72 hours. In controls, serum liver enzyme levels were significantly higher in appropriate-for-date (AFD) babies than small-for-date (SFD) babies. Serum enzyme pattern and extent of elevation were comparable between SFD and AFD babies. Degree of serum liver enzyme elevation had no relationship with severity of hypoxic encephalopathy. Conclusion: Serum liver enzyme elevation is common in BA; it peaks at 24-72 hours followed by a sharp decline by 6-12 days of age. Pattern and extent of enzyme elevation are comparable between SFD and AFD babies.