Implementation of Dimer-based Screening System in Escherichia coli BL21(DE3) for Selection of Actinomycetes Compounds as Anti-HIV Candidate

Actinomycetes are reported to have inhibitory activity against several types of Human Immunodeficiency Virus proteases, enzyme with major role in the process of maturation of the virus thus it can infect new cells. Therefore, exploration of Indonesia’s actinomycetes species is expected to be a breakthrough for HIV treatment. In this study, selection of anti-HIV candidate compounds was conducted using a dimer-based screening system on recombinant Escherichia coli BL21(DE3). The construct includes the fusion of the AraC DNA binding domain + HIV-1 protease as the regulator and the green fluorescence protein as the reporter. Confirmation of the plasmid construct was carried out by PCR which showed size of ~1,076 bp. Sequencing analysis proved 100% similarity and identity between construct used in this study and one previously designed. SDS-PAGE showed the presence of band in the size of ~24 kDa equal to the size of the fusion protein. Compounds BLH 1-12 (2) EA, MAE 1-13 EA, BLH 1-1 EA, BLH 7-5 MetA, LC 98 (1) EA, exhibited consistent and significant protease-HIV inhibitory activity at certain concentrations. Thus, in this study, dimer-based screening system is considered to be able to detect actinomycetes as a new anti-HIV candidate for the protease inhibitor group

Kemampuan Representasi Siswa Sma Berdasarkan Gaya Belajar (Vark) Dan Hubungannya Dengan Penguasaan Konsep Pada Materi Pertumbuhan Dan Perkembangan Tumbuhan

Penelitian ini berjudul kemampuan representasi siswa SMA berdasarkan gaya belajar visual, aural, read/write, dan kinesthetic (VARK) dan hubungannya dengan penguasaan konsep pada materi pertumbuhan dan perkembangan tumbuhan. Penelitian ini bertujuan untuk memperoleh gambaran mengenai profil kemampuan representasi siswa SMA berdasarkan gaya belajar VARK dan mengetahui hubungan antara kemampuan representasi siswa dengan penguasaan konsepnya pada materi pertumbuhan dan perkembangan tumbuhan. Penelitian ini bersifat deskriptif. Instrumen yang digunakan berupa kuesioner gaya belajar untuk menjaring data gaya belajar siswa, soal pilihan berganda untuk menjaring data penguasaan konsep siswa, soal uraian untuk menjaring data kemampuan representasi siswa, dan kuesioner tanggapan siswa untuk mengetahui penggunaan bentuk-bentuk representasi oleh siswa dalam pembelajaran biologi. Hasil analisis data menunjukkan bahwa siswa dengan gaya belajar visual dan read/write memiliki kemampuan representasi yang kurang, sedangkan siswa dengan gaya belajar aural dan kinesthetic memiliki kemampuan representasi yang sangat kurang. Terdapat hubungan yang positif dan berkekuatan sedang antara kemampuan representasi dengan penguasaan konsep siswa visual dan siswa aural, hubungan yang positif dan berkekuatan lemah antara kemampuan representasi dengan penguasaan konsep siswa read/write, dan hubungan yang negatif dan berkekuatan lemah antara kemampuan representasi dengan penguasaan konsep siswa kinesthetic. Kesimpulan yang dapat diambil adalah terdapat perbedaan kemampuan representasi pada setiap kelompok gaya belajar dan adanya hubungan yang berbeda pula antara kemampuan representasi siswa dengan penguasaan konsepnya pada masing-masing kelompok gaya belajar. Kata kunci : gaya belajar VARK, kemampuan representasi, penguasaan konsep

Implementation of Dimer-based Screening System in Escherichia coli BL21(DE3) for Selection of Actinomycetes Compounds as Anti-HIV Candidate

Actinomycetes are reported to have inhibitory activity against several types of Human Immunodeficiency Virus proteases, enzyme with major role in the process of maturation of the virus thus it can infect new cells. Therefore, exploration of Indonesia’s actinomycetes species is expected to be a breakthrough for HIV treatment. In this study, selection of anti-HIV candidate compounds was conducted using a dimer-based screening system on recombinant Escherichia coli BL21(DE3). The construct includes the fusion of the AraC DNA binding domain + HIV-1 protease as the regulator and the green fluorescence protein as the reporter. Confirmation of the plasmid construct was carried out by PCR which showed size of ~1,076 bp. Sequencing analysis proved 100% similarity and identity between construct used in this study and one previously designed. SDS-PAGE showed the presence of band in the size of ~24 kDa equal to the size of the fusion protein. Compounds BLH 1-12 (2) EA, MAE 1-13 EA, BLH 1-1 EA, BLH 7-5 MetA, LC 98 (1) EA, exhibited consistent and significant protease-HIV inhibitory activity at certain concentrations. Thus, in this study, dimer-based screening system is considered to be able to detect actinomycetes as a new anti-HIV candidate for the protease inhibitor group.</jats:p

Evaluation of in-house dengue real-time PCR assays in West Java, Indonesia

Dengue is an infectious disease caused by infection of dengue virus (DENV) transmitted by Aedes aegypti and Aedes albopictus. In Indonesia, dengue commonly occurs with an increasing incidence rate annually. It is known that early detection of dengue infection is one of the keys to controlling this disease outbreak. Rapid and accurate early detection to diagnose dengue can be achieved by molecular tests, one of which is through a real-time PCR method. However, real-time PCR assay for dengue developed based on Indonesian DENV sequences has not been available. Therefore, we developed in-house dengue real-time PCR (SYBR- and TaqMan-based) assays and evaluated those assays in routine clinical testing in the community. These assays target the 3′ UTR region of the four DENV serotypes and was found to be specific for DENV. The most sensitive assay was the TaqMan assay with the LOD95% of 482 copy/ml, followed by the SYBR assay with the LOD95% of 14,398 copy/ml. We recruited dengue suspected patients from three primary health care services in West Java, Indonesia to represent the community testing setting. Dengue infection was examined using the two in-house real-time PCR assays along with NS1, IgM, and IgG rapid diagnostic tests (RDT). In total, as many as 74 clinical specimens of dengue suspected patients were included in this study. Among those patients, 21 were positive for TaqMan assay, 17 were positive for SYBR assay, nine were positive for NS1 test, six were positive for both IgG and IgM tests, and 22 were positive for IgG test only. Compared with our in-house TaqMan assay, the sensitivity of NS1 test, IgM test, and IgG test were 42.86%, 14.29%, and 28.57% respectively. Among these three RDT tests, NS1 showed 100% specificity. Thus, our study confirmed that NS1 test showed high specificity, indicating that a positive result of NS1 can be confidently considered a dengue case. However, NS1, IgM, and IgG tests with RDT are not enough to diagnose a dengue case. We suggest applying the high sensitivity and specificity rRT-PCR test as the gold standard for early detection and antibody test as a follow-up test for rRT-PCR negative cases