Judul: Studi In-vitro dan In-vivo Efek Radioprotektif Rosela (Hibiscus Sabdariffa Linn.) terhadap Radiasi Ionisasi Radiodiagnostik Berulang
Abstrak: The purpose of this study is to determine the natural radioprotective effect of ethanolic extract of roselle (Hibiscus sabdariffa L.) through the in-vitro and invivo study of mice that were exposed by ionizing radiation from recurrent radiodiagnostic. In in-vitro study, splenic lymphocytes were cultured in different concentration of ethanolic extract of roselle. Splenic lymphocytes were divided in two groups; with radiation exposure and without radiation exposure. The numbers of lymphocyte were calculated at 1, 2 and 3 days after radiation of each group. In in-vivo study, mice supplemented with ethanolic extract of roselle dose 50 mg/kg body weight prior to radiation for 60 days and 30 days after recovery for clinical and pathological evaluation. Radiation from radiodiagnostic radiography exposure performs repeated every 2 days. Forty eight adult mice were divided in 4 groups; control (K), radiation (P), roselle (R) and roselle with radiation (RP). Clinical data were collected for live survival, body weight, and peripheral blood characteristic. Pathological data were collected for relative organ weight and histopathological finding of bone marrow and spleen at 4 and 8 weeks after radiation; 8 and 12 weeks after 30 days recovery. The in-vitro study clearly showed that roselle enhances the splenic lymphocyte proliferation and maintained amount of cells (p<0.05). The in-vivo study showed that roselle maintained peripheral blood characteristic (p<0.05), however did not affect the mice live survival and body weight (p>0.05). Pathological evaluation showed that relative organ weight, hematopoietic bone marrow cells, and white pulpa area of spleen were significant different between groups (p<0.05).
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Judul: Efek Radioprotektif Ekstrak Rosela (Hibiscus sabdariffa L.) terhadap Radiasi Ionisasi Radiodiagnostik Berulang: Studi Gambaran Eritrosit Darah Perifer Mencit (Mus musculus).
Abstrak: The aim of this study was to determine the radioprotective effect of ethanolic roselle extract (Hibiscus sabdariffa L.) in recurrent radiodiagnostic ionizing radiation on peripheral red blood cells of mice (Mus musculus). Fourty eight male mice were used in this study and divided into 4 group; K-(physiological saline without radiation), K+ (physiological saline with radiation), R- (roselle extract without radiation), R+ (roselle extract with radiation). The mice were treated with 50 mg per kg body weight ethanolic roselle extract prior to radiation exposure. Following these treatment, the mice were exposed with ionizing radiation at dose 0.2 mSv every two days for 8 weeks. Bloods sample were collected of each group at week 0 before treatment, 2, 4, 6, and 8 week after treatment. The blood samples were taken also at 4 and 8 week, which previously without radiation exposure for 30 days as recovery phase. The result showed that radiation exposure causes an increasing the number of Mean Corpuscular Volume (MCV), Mean Corpuscular Hemoglobin (MCH), Mean Corpuscular Hemoglobin Concentration (MCHC) and Howell Jolly Bodies in the peripheral blood tissue. However ethanolic roselle extract causes a decreasing number of the parameters. This result indicated that ethanolic roselle extract has radioprotective effect on of red blood cells repair process from ionizing radiation destruction (p<0.05).
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Judul: Closed Knight’s Tour pada Papan Catur Berbentuk Persegi Panjang dengan Ukuran Maksimal 8 × 8
Abstrak: Closed Knight’s Tour merupakan langkah kuda yang mengunjungi setiap kotak pada papan catur tepat satu kali dengan langkah kuda berawal dan berakhir pada kotak yang sama. Graf yang terbentuk dari closed knight’s tour dinotasikan sebagai graf G(m,n), dengan m adalah banyaknya baris dan n adalah banyaknya kolom. Graf tersebut memuat Hamiltonian cycle. Sebuah graf terhubung G adalah graf bipartite jika dan hanya jika graf tersebut tidak memiliki cycle dengan panjang ganjil. Papan catur yang memenuhi syarat cukup untuk memiliki closed knight’s tour adalah papan catur berukuran 5 × 6, 5 × 8, 6 × 6, 6 × 7, 6 × 8, 7 × 8, dan 8 × 8.
Keyword: bipartite, closed knight’s tour, hamiltonian cycle, knight’s tour, teori graf