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PENGGUNAAN [3H]-LEUSIN UNTUK MEMPELAJARI SENYAWA KOMPLEKS PERSEITOL·K+ YANG DIISOLASI DARI BENALU ALUS Scurrula fusca SEBAGAI INHIBITOR SINTESIS PROTEIN PADA SEL
No full textTelah dilakukan pengujian aktivitas senyawa perseitol·K+ (2) yang diisolasi dari benalu alus Scurrula fusca (BL.) G. DON terhadap inhibisi sintesis protein oleh sel kanker Ehrlich ascites dari tikus. Pengujian dilakukan dengan menggunakan L-[3,4,5-3H(N)] leusin dan pengukuran dilakukan dengan pencacah sintilasi cair. Hasil percobaan menunjukkan bahwa senyawa isolat tersebut mnunjukkan aktivitas inhibisi sebesar 13% pada konsentrasi sampel 10-7 M. Aktivitas ini lebih tinggi dibandingkan senyawa perseitol (3) tanpa ion K+ yang hanya menunjukkan aktivitas inhibisi sebesar 5%. Keberadaan ion K+ dalam senyawa kompleks merupakan faktor esensial dalam aktivitasnya sebagai inhibitor sintesis protein oleh sel kanker. Percobaan yang sama yang dilakukan terhadap berbagai komposisi campuran senyawa perseitol (3) dan ion K+ dengan perbandingan molar 24:1, 22:1, 20:1, dan 18:1 menunjukkan bahwa komposisi perseitol : K+ = 20:1 memberikan aktivitas inhibisi tertinggi terhadap sintesis protein yaitu 40% pada konsentrasi 10-4 M. Aktivitas inhibisi ini lebih tinggi dibandingkan cycloheximide sebagai kontrol positif (25% inhibisi pada 0.5×10-6 M). Hal ini diduga pada komposisi perbandingan molar tersebut, perseitol (3) dan ion K+ membentuk senyawa kompleks perseitol·K+ seperti isolat benalu alus. Selain pengaruh keberadaan ion K+, perbandingan molar 20:1 merupakan faktor yang sangat berperan dalam aktivitasnya sebagai inhibitor sintesis protein oleh sel kanker
 
PENGGUNAAN [3H]-LEUSIN UNTUK MEMPELAJARI SENYAWA KOMPLEKS PERSEITOL·K+ YANG DIISOLASI DARI BENALU ALUS Scurrula fusca SEBAGAI INHIBITOR SINTESIS PROTEIN PADA SEL
Full text linkTelah dilakukan pengujian aktivitas senyawa perseitol·K+ (2) yang diisolasi dari benalu alus Scurrula fusca (BL.) G. DON terhadap inhibisi sintesis protein oleh sel kanker Ehrlich ascites dari tikus. Pengujian dilakukan dengan menggunakan L-[3,4,5-3H(N)] leusin dan pengukuran dilakukan dengan pencacah sintilasi cair. Hasil percobaan menunjukkan bahwa senyawa isolat tersebut mnunjukkan aktivitas inhibisi sebesar 13% pada konsentrasi sampel 10-7 M. Aktivitas ini lebih tinggi dibandingkan senyawa perseitol (3) tanpa ion K+ yang hanya menunjukkan aktivitas inhibisi sebesar 5%. Keberadaan ion K+ dalam senyawa kompleksmerupakan faktor esensial dalam aktivitasnya sebagai inhibitor sintesis protein oleh sel kanker. Percobaan yang sama yang dilakukan terhadap berbagai komposisi campuran senyawa perseitol (3) dan ion K+ dengan perbandingan molar 24:1, 22:1, 20:1, dan 18:1 menunjukkan bahwa komposisi perseitol : K+ = 20:1 memberikan aktivitas inhibisi tertinggi terhadap sintesis protein yaitu 40% pada konsentrasi 10-4 M. Aktivitas inhibisi ini lebih tinggi dibandingkan cycloheximide sebagai kontrol positif (25% inhibisi pada 0.5×10-6 M). Hal ini diduga pada komposisi perbandingan molar tersebut, perseitol (3) dan ion K+ membentuk senyawa kompleks perseitol·K+ seperti isolat benalu alus. Selain pengaruh keberadaan ion K+, perbandingan molar 20:1 merupakan faktor yang sangat berperan dalam aktivitasnya sebagai inhibitor sintesis protein oleh sel kanke
Safety Evaluation of the Ethyl Acetate Extract on Irradiated Tea Parasite: Acute Toxicity Study on Mice
Full text linkMany studies of the pharmacological efficacy of tea parasite and the use of ionizing radiation for decontamination of microbes and extending shelf life have been reported, but there is no information on its safety, such as the acute toxicity. In this study, the acute toxicity of two ethyl acetate extracts from unirradiated and irradiated (irradiation dose of 10 kGy) tea parasites Scurrula atropurpurea on Swiss Webster mice have been examined. The observation was done after the treatment of a single oral dose of ethyl acetate extract in various dose groups, i.e.: control (0 g/kg of mice body weight), D1 (0.625 g/kg), D2 (1.25 g/kg), D3 (2.5 g/kg) D4 (5 g/kg), D5 (10 g/kg) by observing the effect on behavioral response (pharmacological profile), the body weight gains and mortality until the day 14 th . At the last day, the observation of vital organs has also been done. The result showed thatno acute toxicity was found in mice treated with a single oral dose of ethyl acetate extract from unirradiated tea parasite and irradiated tea parasite at the dose of 10 kGy. At the dose up to 10 g/kg (equivalent to 77.6 g of extract which administered to human), the normal body weight gains were observed in mice of all dose groups, no mice deaths in any of the dose groups, and no significant change (p > 0.05) in organ weights relative to the body weight i.e.: liver, spleen, kidneys, lung, heart, testes and seminal vesicle (for male), and ovaries and uterus (for female). The approximate lethal doses for male and female mice were determined to be higher than 10 g/kg of mice body weight. It is suggested that the treatment of ethyl acetate extract from unirradiated and irradiated tea parasites until dose up to 10 g/kg of mice body weight was stillsafe
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Aplikasi Hidrogel Poli-(akrilamida) Hasil Iradiasi Gamma untuk Adsorpsi Zat Warna Biru Metilen dalam Larutan
No full text
The aim of theresearch is to study the capacity of poly(acrylamide)(PAAM) hydrogel to adsorp a syntheticdye of methylene blue (MB). PAAM hydrogel was synthesized by varying gamma radiationdoses (20-40 kGy), and was then processed to dried powder (120 mesh) and used to adsorbMB dye from the aqueous solution. The batch adsorption experiment was carried out byvarying contact time (0-120 min.), initial concentration of MB (2-10 mg/L), adsorbent dose (0-120 mg), and the chemical changes of hydrogels were characterized by Fourier Transforminfra red (FTIR). The adsorption process of MB was examined with Langmuir and Freundlichisotherm models. The results showed that the hydrogel prepared at 20 kGy had higheradsorption capacities onto MB compare to the hydrogel at 30 and 40 kGy. With increasinghydrogel doses, the MB adsorbed increase. The results of Langmuir and Freundlich isothermexamination obtained the coefficient correlation (R2) of 0,9914 and 0,9964 with maximumadsorption capacity 1.67 mg/g at a solution pH of 6.5. Modification of PAAM hydrogels willbe potentially as dyes adsorbent.
IRRADIATION EFFECTS ON INSECTICIDES AS A POLLUTANT MODEL IN AQUEOUS SOLUTION
Full text linkDegradation of some insecticides i.e.: fenitrothion, prothiofos, and cypermetrin as a model pollutant was carried out using gamma irradiation of 60Co. Irradiation-induced of fenitrothion in solution acid medium gave the significant effect on the decrease of its concentration. The optimum condition for degradation of fenitrothion (55.5 mg/L) was irradiation at 6 kGy with aeration in initial pH 5.6. At this condition, the concentration of fenitrothion decreased up to 97%. Determination of organic acids in irradiated product by HPLC method showed that oxalic acid and formic acid were clarified as organic acid-degraded products of fenitrothion with the concentration of 23.0 mg/L and 2.5 mg/L respectively. The irradiation of prothiofos in aqueous solution (50 mg/L), showed that irradiation at a dose of 8 kGy and initial pH 7 gave the optimum degradation. At this condition, the concentration of prothiofos decreased up to 98%. Determination of irradiated product by HPLC method showed that oxalic acid (18 mg/L) was clarified as organic acid-degraded product of prothiofos. In the case of cypermetrin, the optimum condition for its degradation was irradiation with aeration of cypermetrin (40 mg/L) at a dose of 20 kGy, initial pH 11, and adding the catalyst 0.05% of FeCl3. At that condition, cypermetrin decreased up to 87% and COD of solution decreased up to 78%. The organic acid detected at optimum condition as degradation products were oxalic acid (1.1 g/L), maleic acid (9.0 g/L), formic acid (127.0 g/L), and acetic acid (286.0 g/L). From these results, it could be concluded that ionizing radiation can be used as a tool to degrade insecticides as organic pollutants
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