Judul: Study of the BACE1 Gene Expression as Molecular Marker for Alzheimer's Disease in Long-tailed Macaques (Macaca fascicularis) Brain
Abstrak: Penyakit Alzheimer adalah gangguan neurodegenerative yang menyebabkan penurunan daya ingat dan fungsi kognitif pada penderitanya. Penggunaan monyet ekor panjang dilakukan karena secara anatomis maupun fisiologis memiliki kemiripan dengan manusia dibandingkan hewan coba lainnya. Penelitian ini menganalisis ekspresi gen Β-site Amyloid Precursor Protein Cleaving Enzyme 1 (BACE1) di otak sebagai marka molekuler penyakit Alzheimer. Sampel diekstraksi dan diolah menggunakan Reverse Transcription quantitative Polymerase Chain Reaction (RT-qPCR) berdasarkan regio otak hipokampus dan korteks prefrontal pada 6 monyet ekor panjang betina dengan kelompok usia dewasa dan tua. Level ekspresi mRNA gen BACE1 dibandingkan dengan gen housekeeping yaitu beta-actin (ACTB). Hasil analisis data statistik menunjukan tidak adanya perbedaan nyata antara ekspresi mRNA gen BACE1 pada perbedaan kelompok usia maupun regio otak. Namun, hasil perhitungan menunjukan kecenderungan lebih tinggi pada regio hipokampus dan kelompok usia dewasa dibandingkan korteks dan kelompok usia tua pada monyet ekor panjang., Alzheimer’s disease is is a neurodegenerative disorder that cause decline in memory, and cognitive function in the patient’s. The use long-tailed macaques is conducted due to their anatomical and physiological similarities to humans compared to other experimental animals. This study analyzed the expression of the Β-site Amyloid Precursor Protein Cleaving Enzyme 1 (BACE1) gene in the brain as molecular marker of Alzheimer's disease. Samples were extracted and processed using Reverse Transcription quantitative Polymerase Chain Reaction (RT-qPCR) from the hippocampus and prefrontal cortex regions of six female long-tailed macaques with adult and old age groups. The mRNA expression levels of the BACE1 gene were compared to the beta-actin (ACTB) as housekeeping gene. The data analysis showed no significant differences in the mRNA expression of the BACE1 gene between different age groups or brain regions. However, there was a tendency that mRNA expression levels in the hippocampus region and the adult age group higher than the cortex region and the old age group in the long-tailed macaques.
Keyword: BACE1, monyet ekor panjang, otak, penyakit Alzheimer, RT-qPCR, Alzheimer’s disease, BACE1, brain, long-tailed macaques, RT-qPCR

Judul: Quantification of APH1A Gene Expression as Alzheimer Molecular Marker in Long-Tailed Macaque (Macaca fascicularis)
Abstrak: Penyakit Alzheimer merupakan penyakit neurodegeneratif progresif yang ditandai akumulasi protein amyloid-β (Aβ) pada otak. Anterior pharynx defective-1 homolog A (APH1A) merupakan salah satu gen yang berperan dalam pembentukan Aβ. Untuk mengetahui patogenesis Alzheimer, monyet ekor panjang (Macaca fascicularis) telah digunakan sebagai hewan model karena memiliki kesamaan karakteristik dengan manusia penderita Alzheimer, yaitu pembentukan plak Aβ pada otak. Penelitian ini bertujuan untuk mengukur tingkat ekspresi gen APH1A sebagai marka molekuler Alzheimer pada otak M. fascicularis. Teknik reverse transcription-quantitative polymerase chain reaction (RT-qPCR) digunakan untuk kuantifikasi mRNA spesifik. Sampel yang digunakan berupa potongan hipokampus dan korteks yang berasal dari 8 ekor monyet yang dikelompokkan berdasarkan usia, yaitu muda dan tua. Data dianalisis berdasarkan kelompok usia, regio otak, dan regio otak pada kelompok usia. Secara keseluruhan, hasil tidak menunjukkan perbedaan nyata dalam ekspresi gen APH1A pada kelompok usia maupun di regio otak, meskipun jumlah transkripnya cenderung lebih tinggi pada usia muda dan korteks. Perbedaan yang menarik terlihat ketika membandingkan kelompok usia di wilayah hipokampus, dimana ekspresi gen APH1A signifikan lebih tinggi ditemukan pada kelompok usia muda. Studi ini menegaskan potensi M. fascicularis sebagai model untuk pemahaman molekuler penyakit Alzheimer dengan data penting ekspresi gen APH1A di otak, yang dapat membantu pengembangan terapi bertarget., Alzheimer's disease is a progressive neurodegenerative disorder characterized by amyloid-β (Aβ) accumulation in the brain. Anterior pharynx defective-1 homolog A (APH1A) gene plays role in Aβ formation. To study the disease's pathogenesis, long-tailed macaque (Macaca fascicularis) was used as animal models due to their Aβ plaque formation similarity to humans with Alzheimer's. The study aimed to measure APH1A gene expression as an Alzheimer's molecular marker in the M. fascicularis brain. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was used for specific mRNA quantification. Samples from the hippocampus and cortex of eight monkeys, grouped by age (young and old), were analyzed by age group, brain region, and brain region by age group. Overall, no significant differences in APH1A gene expression were observed in age groups or brain regions, though there was a tendency for higher transcripts in the young and cortex. However, an intriguing finding emerged when comparing age groups in the hippocampal region, where significantly higher APH1A gene expression was detected in the young monkeys. This study highlights the potential of M. fascicularis as a model for understanding Alzheimer's molecular aspects and provides crucial data on APH1A gene expression in the brain, which may contribute to the development of targeted therapies.
Keyword: Alzheimer's disease, APH1A, Long-tailed macaque

Judul: Hamiltonian formulation for linear waves motion in two layers fluid
Abstrak: The surface wave could be considered as a wave that separates two fluids, namely water and air. Based on this assumption, it is introduced the interfacial wave, a wave between two layers of fluid with different density. The formulation of interfacial waves motion begins with deriving the base equation of irrotational ideal fluid. Furthermore, according to irrotational fluid assumption, the base equation can be stated in velocity potential. In this derivation, the fluids domain is assumed to be restricted by rigid lid boundary conditions, both at the upper and lower limit. Therefore, the interfacial waves motion can be explained in a hamiltonian formulation. In the hamiltonian formulation, total energy is defined as the sum of kinetic and potential energy. The hamiltonian system is obtained from reduction of kinetic energy by using the Dirichlet Neumann Operator. The resulted kinetic energy equation is nonlinear. Therefore, this form is linearized by first part of the Taylor expansion. This linearization gives a dispersion relation of linear wave. Based on this dispersion relation, the phase speed of the linear wave depends on the density ratio of the two layers fluid.
Keyword: