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"Background: There is a growing interest In the potential biological effects of electromagnetic fields (EMFS) on human. Mobile phone is currently known as one of the most world wide used tool which emitted, up to certain extent, EMFS. We try to explore the possible adverse effects of mobile phone on the function of the reproductive system, particularly focused on serum testosterone level, as one of the most important parameter of reproductive function. Objective: To evaluate the biological effect of RFEMR of mobile phone on serum testosterone level. Method: As a model, we exposed 9 New Zealand Rabbits to RFEMR of mobile phone, Nokia 8110, 900 MHz, built in antena,with Specific Absorption Rate (SAR) of 0.6 mW/cm2 • Total serum testosterone level was evaluated from 2 ml of rabbit blood collected prior and after the exposure. Group A exposed to 10 calls per day, group B exposed to 20 calls per day,and group C exposed to 30 calls per day ; duration of each call was 120 seconds, within 7 consecutive days. Result: Statistical analysis show a significant correlation was shown between RFEMR of mobile phone and serum total testosterone level (p = 0.0208; a < 0.15) as well as between intensity of radiation and serum total testosterone level (p = 0.0753; a < 0.15 ). Conclusion: RFEMR of mobile phone has an impact on serum total testosterone level."

"Nama : Irena UjiantiProgram Studi : Program Magister Ilmu BiomedikJudul Tesis :Dampak Restriksi Vitamin B12 Terhadap Kadar Homosistein, Resistensi Insulin Dan Gambaran NAFLDPembimbing : dr. Imelda Rosalyn Sianipar, M.Biomed, Ph.D dan Dr. dr. Dewi Irawati Soeria Santoso, MS Latar Belakang: Perlemakan hati merupakan penyakit hati kronik terbesar di dunia. Kondisi yang mendasari terjadinya perlemakan hati dimulai dari kondisi resistensi insulin. Salah satu patogenesis terjadinya resistensi insulin adalah gangguan pada pensinyalan insulin oleh zat toksik tertentu yang akan berinteraksi dengan protein yang menyusun jalur pensinyalan insulin. Peningkatan homosistein dikaitkan dengan resistensi insulin. Homosistein akan meningkat sejalan dengan terganggunya jalur metilasi dari siklus metionin. Pemberian diet restriksi vitamin B12 akan memicu terjadinya resistensi insulin lewat jalur stres oksidatif yang ditimbulkan oleh homosistein.Bahan dan Metode: Penelitian ini menggunakan metode eksperimental terhadap 24 tikus Sprague Dawley jantan Rattus norvegicus, 300-350 gram, usia 35-40 minggu , terbagi ke dalam 4 kelompok yaitu kontrol K , Kelompok perlakuan 4 minggu P-1 , Kelompok Perlakuan 8 minggu P-2 dan kelompok perlakuan 12 minggu P-3 . Pada Kelompok kontrol, diberikan diet standar AIN-93M sedangkan kelompok perlakuan diberikan pakan modifikasi restriksi vitamin B12 AIN-93 sesuai usia perlakuan.Hasil: Kelompok perlakuan 8 minggu paling baik dalam menggambarkan kondisi perlemakan hati dibandingkan kelompok kontrol dan perlakuan 4 minggu, sedangkan kelompok perlakuan 12 minggu telah mempresentasikan kondisi NASH Non Alcoholic Steatohepatitis . Hasil ini sejalan dengan kondisi peningkatan homosistein plasma pada kelompok kontrol dan masing-masing usia perlakuan.Kesimpulan: Peningkatan homosistein akibat diet restriksi vitamin B12 mengakibatkan kondisi steatosis dan steatohepatitits pada hati, sebagai akibat dari kondisi resistensi insulin dan kerusakan sebagian dari sel beta pankreas. Kata kunci: Homosistein, Restriksi vitamin B12, NAFLD, Resistensi Insulin

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ABSTRACT Name Irena UjiantiStudy Program Master Program of Biomedical SciencesThesis Title Impact of Vitamin B12 Restriction on Homocysteine Levels, Insulin Resistance and NAFLDCounselor dr. Imelda Rosalyn Sianipar, M.Biomed, Ph.D. dr. Dewi Irawati Soeria Santoso, MS Background The fatty liver is the biggest chronic liver disease in the world. The underlying condition of fatty liver starts from the condition of insulin resistance. One of the pathomechanisms of insulin resistance is the disturbance in insulin signaling by certain toxic substances that will interact with one of the proteins that make up the insulin signaling pathway. Increased homosisteine is associated with insulin resistance. Homosisteine will increase in line with the disruption of the methionin metionin pathway. Dietary vitamin B12 deficiency will trigger insulin resistance through the path of oxidative stress generated by homocysteine.Materials and Methods This study used an experimental method of 24 male Sprague Dawley rats Rattus norvegicus, 300 400 gram, age 7 8 months , divided into 4 groups kontrol K , 4 weeks treatment group P 1 , 8 weeks treatment group P 2 and 12 week treatment group P 3 . In the kontrol group, a standard AIN 93 diet was administered while the feeding group was administered vitamin A deficiency deficiency AIN 93M according to treatment age.Results The best 8 weeks treatment group described the conditions of fatty liver compared to the 4 week kontrol and treatment group, while the 12 week treatment group presented the NASH condition. These results are consistent with the elevated plasma homocysteine conditions in the kontrol group and each treatment age.Conclusion Increased homocysteine due to dietary vitamin B12 deficiency is able to induce the condition of steatosis and steatohepatitits in the liver, as a result of the condition of insulin resistance and beta cell pancrease damage as the underlying patomechanism. Keywords Homocysteine, vitamin B12 Deficiency, NAFLD, Insulin Resistance "

"Pendahuluan: Stres oksidatif adalah kondisi yang terjadi saat ada gangguan keseimbangan antara sintesis dan detoksifikasi reactive oxygen species (ROS) di dalam sel dan jaringan tubuh. Kedua jenis ROS, yaitu eksogen dan endogen menyebabkan modifikasi oksidatif pada makromolekul seluler utama. Salah satu biomarker yang dapat digunakan adalah malondialdehid (MDA), hasil dari peroksidasi lipid. Puasa adalah salah satu bentuk restriksi kalori, dan hasil dari penelitian mengenai puasa menunjukkan dampak positif pada subjek penelitian. Namun, penelitian ini belum banyak dilakukan pada hewan dengan level yang lebih tinggi, seperti kelinci. Khususnya, ROS memiliki dampak negatif pada regulasi kalsium di jantung yang dapat menyebabkan aritmia dan cardiac remodeling. Penelitian ini akan menelusuri dampak dari puasa intermiten dan puasa berkepanjangan terhadap kadar MDA sebagai biomarker stres oksidatif pada jantung kelinci New Zealand white. Metode: Sampel jantung kelinci New Zealand white dengan berat masing-masing 100 mg dihomogenisasi dengan 1 ml phosphate-buffered saline (PBS). Analisis MDA diukur dengan metode Will’s dengan menambahkan TBA 0.67% pada setiap sampel dan diinkubasi dalam water bath 100° C selama 10 menit. Reaksi antara MDA dan TBA menghasilkan warna merah muda. Absorbansi dibaca pada 530 nm dengan spektrofotometer yang mencerminkan konsentrasi MDA. Nilai konsentrasi MDA dapat ditetapkan dengan menggunakan kurva linear. Analisis data dilakukan dengan software IBM SPSS Statistics. Hasil: Rata-rata konsentrasi MDA pada grup kontrol (JK), puasa intermiten (JIF), dan puasa berkepanjangan (JPF) berturut-turut adalah 0.215 nmol/ml, 0.094 nmol/ml, dan 0.090 nmol/ml. Terdapat perbedaan yang signifikan antara JK dengan JIF dan JK dengan JPF (p = 0.006 dan p = 0.005). Namun, tidak terdapat perbedaan signifikan antara JIF dengan JPF (p = 0.936). Kesimpulan: Penelitian ini menemukan bahwa kadar MDA pada grup puasa intermiten dan berkepanjangan lebih rendah bermakna daripada grup kontrol. Sebagai bentuk restriksi kalori, bisa disimpulkan bahwa puasa memiliki efek dalam menurunkan level stres oksidatif dengan menggunakan MDA sebagai biomarker. Tidak ada perbedaan yang signifikan antara puasa intermiten dan puasa berkepanjangan. Ini bisa menandakan bahwa hasil yang serupa dapat didapat dengan periode puasa yang lebih singkat.

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Introduction: Oxidative stress is defined as the condition in which there is disrupted balance between the synthesis and detoxification of reactive oxygen species (ROS) in bodily cells and tissues. Both exogenous and endogenous ROS are responsible for oxidative modification of the major cellular macromolecules. One of the biomarkers that can be used is malondialdehyde (MDA), which is a result of lipid peroxidation. Fasting is a form of calorie restriction, with results showing many of the subjects benefitting from said fasting. However, the studies have not been conducted on higher-level animals (i.e. rabbits). In particular, ROS have negative effect on calcium regulation in the heart which can lead to arrhythmia and cardiac remodeling. This research will therefore explore the impact of intermittent and prolonged fasting towards MDA as the biomarker for oxidative stress in the heart of New Zealand White rabbit.

Methods: Samples of New Zealand white rabbit heart tissues weighing 100 mg each were homogenized in 1 ml of phosphate-buffered saline (PBS). MDA analysis was performed using Will’s method by adding TBA 0.67% into each sample and incubating in 100° C water bath for 10 minutes. The reaction between the MDA and TBA produced the color pink. The absorbance was read at 530 nm using spectrophotometer, which reflects the concentration of the MDA by plotting the absorbance into a linear curve. Finally, data analysis was performed using IBM SPSS Statistics software.

Results: The averages for the MDA concentration in control (JK), intermittent fasting (JIF), and prolonged fasting (JPF) groups respectively were 0.215 nmol/ml, 0.094 nmol/ml, and 0.090 nmol/ml. There were significant differences between JK with JIF as well as JK with JPF (p = 0.006 and p = 0.005, respectively). However, there was not a significant difference between JIF and JPF (p = 0.936).

Conclusion: Our study found that there were significantly lower levels of MDA in intermittent fasting and prolonged fasting groups compared to the control group. As a form of calorie restriction, it can be concluded that fasting has an effect in reducing oxidative stress, on the basis of using MDA as its biomarker. There was no significant difference between the intermittent fasting and prolonged fasting groups, which implies that similar results can be achieved with shorter fasting periods."

"ABSTRAKPaduan aluminium (AlMg3) digunakan pada reaktor nuklir terutama pada tangkireaktor, beam tube dan komponen lainnya yang ada didalam kolam reaktor. Salahsatu reaktor yang menggunakan material AlMg3 adalah reaktor yang ada di Serpong.Kolam reaktor berisi air sebagai media pendingin. Media pendingin didalam kolamdisebut Primer menggunakan air non mineral (air demin). Kualitas air yangdigunakan akan sangat berpengaruh terhadap integritas struktur, sistem dankomponen reaktor. PH air pendingin primer sekitar 5,8