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Dive into the research topics where Raymond R. Tjandrawinata is active.

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Featured researches published by Raymond R. Tjandrawinata.


British Journal of Cancer | 1997

Induction of cyclo-oxygenase-2 mRNA by prostaglandin E2 in human prostatic carcinoma cells.

Raymond R. Tjandrawinata; R. Dahiya; Millie Hughes-Fulford

Prostaglandins are synthesized from arachidonic acid by the enzyme cyclo-oxygenase. There are two isoforms of cyclooxygenases: COX-1 (a constitutive form) and COX-2 (an inducible form). COX-2 has recently been categorized as an immediate-early gene and is associated with cellular growth and differentiation. The purpose of this study was to investigate the effects of exogenous dimethylprostaglandin E2 (dmPGE2) on prostate cancer cell growth. Results of these experiments demonstrate that administration of dmPGE2 to growing PC-3 cells significantly increased cellular proliferation (as measured by the cell number), total DNA content and endogenous PGE2 concentration. DmPGE2 also increased the steady-state mRNA levels of its own inducible synthesizing enzyme, COX-2, as well as cellular growth to levels similar to those seen with fetal calf serum and phorbol ester. The same results were observed in other human cancer cell types, such as the androgen-dependent LNCaP cells, breast cancer MDA-MB-134 cells and human colorectal carcinoma DiFi cells. In PC-3 cells, the dmPGE2 regulation of the COX-2 mRNA levels was both time dependent, with maximum stimulation seen 2 h after addition, and dose dependent on dmPGE2 concentration, with maximum stimulation seen at 5 microg ml(-1). The non-steroidal anti-inflammatory drug flurbiprofen (5 microM), in the presence of exogenous dmPGE2, inhibited the up-regulation of COX-2 mRNA and PC-3 cell growth. Taken together, these data suggest that PGE2 has a specific role in the maintenance of human cancer cell growth and that the activation of COX-2 expression depends primarily upon newly synthesized PGE2, perhaps resulting from changes in local cellular PGE2 concentrations.


Advances in Experimental Medicine and Biology | 1997

Up-regulation of cyclooxygenase-2 by product-prostaglandin E2

Raymond R. Tjandrawinata; Millie Hughes-Fulford

The development of prostate cancer has been linked to high level of dietary fat intake. Our laboratory investigates the connection between cancer cell growth and fatty acid products. Studying human prostatic carcinoma PC-3 cells, we found that prostaglandin E2 (PGE2) increased cell growth and up-regulated the gene expression of its own synthesizing enzyme, cyclooxygenase-2 (COX-2). PGE2 increased COX-2 mRNA expression dose-dependently with the highest levels of stimulation seen at the 3-hour period following PGE2 addition. The NSAID flurbiprofen (5 microM), in the presence of exogenous PGE2, inhibited the up-regulation of COX-2 mRNA and cell growth. These data suggest that the levels of local intracellular PGE2 play a major role in the growth of prostate cancer cells through an activation of COX-2 gene expression.


Phytomedicine | 2011

Olive (Olea europaea) leaf extract effective in patients with stage-1 hypertension: Comparison with Captopril

Endang Susalit; Nafrialdi Agus; Imam Effendi; Raymond R. Tjandrawinata; Dwi Nofiarny; Tania Perrinjaquet-Moccetti; Marian Verbruggen

A double-blind, randomized, parallel and active-controlled clinical study was conducted to evaluate the anti-hypertensive effect as well as the tolerability of Olive leaf extract in comparison with Captopril in patients with stage-1 hypertension. Additionally, this study also investigated the hypolipidemic effects of Olive leaf extract in such patients. It consisted of a run-in period of 4 weeks continued subsequently by an 8-week treatment period. Olive (Olea europaea L.) leaf extract (EFLA(®)943) was given orally at the dose of 500 mg twice daily in a flat-dose manner throughout the 8 weeks. Captopril was given at the dosage regimen of 12.5 mg twice daily at start. After 2 weeks, if necessary, the dose of Captopril would be titrated to 25 mg twice daily, based on subjects response to treatment. The primary efficacy endpoint was reduction in systolic blood pressure (SBP) from baseline to week-8 of treatment. The secondary efficacy endpoints were SBP as well as diastolic blood pressure (DBP) changes at every time-point evaluation and lipid profile improvement. Evaluation of BP was performed every week for 8 weeks of treatment; while of lipid profile at a 4-week interval. Mean SBP at baseline was 149.3±5.58 mmHg in Olive group and 148.4±5.56 mmHg in Captopril group; and mean DBPs were 93.9±4.51 and 93.8±4.88 mmHg, respectively. After 8 weeks of treatment, both groups experienced a significant reduction of SBP as well as DBP from baseline; while such reductions were not significantly different between groups. Means of SBP reduction from baseline to the end of study were -11.5±8.5 and -13.7±7.6 mmHg in Olive and Captopril groups, respectively; and those of DBP were -4.8±5.5 and -6.4±5.2 mmHg, respectively. A significant reduction of triglyceride level was observed in Olive group, but not in Captopril group. In conclusion, Olive (Olea europaea) leaf extract, at the dosage regimen of 500 mg twice daily, was similarly effective in lowering systolic and diastolic blood pressures in subjects with stage-1 hypertension as Captopril, given at its effective dose of 12.5-25 mg twice daily.


The FASEB Journal | 1997

Vibrational force alters mRNA expression in osteoblasts.

Raymond R. Tjandrawinata; V L Vincent; Millie Hughes-Fulford

Serum‐deprived mouse osteoblastic (MC3T3E1) cells were subjected to a vibrational force modeled by NASA to simulate a space shuttle launch (7.83 G rms). The mRNA levels for eight genes were investigated to determine the effect of vibrational force on mRNA expression. The mRNA levels of two growth‐related protooncogenes, c‐fos and c‐myc, were up‐regulated significantly within 30 min after vibration, whereas those of osteocalcin as well as transforming growth factor‐β1 were decreased significantly within 3h after vibration. No changes were detected in the levels of β‐actin, histone H4, or cytoplasmic phospholipase A2 after vibration. No basal levels of cyclooxygenase‐2 expression were detected. In addition, the extracellular concentrations of prostaglandin E2 (PGE2), a potent autocrine/paracrine growth factor in bone, were not significantly altered after vibration most likely due to the serum deprivation state of the osteoblasts. In comparison with the gravitational launch profile, vibrational‐induced changes in gene expression were greater both in magnitude and number of genes activated. Taken together, these data suggest that the changes in mRNA expression are due to a direct mechanical effect of the vibrational force on the osteoblast cells and not to changes in the local PGE2 concentrations. The finding that launch forces induce gene expression is of utmost importance since many of the biological experiments do not dampen vibrational loads on experimental samples. This lack of dampening of vibrational forces may partially explain why 1‐G onboard controls sometimes do not reflect 1‐G ground controls. These data may also suggest that scientists use extra ground controls that are exposed to launch forces, have these forces dampened on launched samples, or use facilities such as Biorack that provide an onboard 1‐G centrufuge in order to control for space shuttle launch forces.—Tjandrawinata, R. R., Vincent, V. L., Hughes‐Fulford, M. Vibrational force alters mRNA expression in osteoblasts. FASEB J. 11, 493–497 (1997)


International Journal of Pharmaceutics | 2016

Physicochemical and mechanical properties of paracetamol cocrystal with 5-nitroisophthalic acid

Stevanus Hiendrawan; Bambang Veriansyah; Edward Widjojokusumo; Sundani Nurono Soewandhi; Saleh Wikarsa; Raymond R. Tjandrawinata

We report novel pharmaceutical cocrystal of a popular antipyretic drug paracetamol (PCA) with coformer 5-nitroisophhthalic acid (5NIP) to improve its tabletability. The cocrystal (PCA-5NIP at molar ratio of 1:1) was synthesized by solvent evaporation technique using methanol as solvent. The physicochemical properties of cocrystal were characterized by powder X-ray diffraction (PXRD), differential scanning calorimetry (DSC), thermogravimetry analysis (TGA), fourier transform infrared spectroscopy (FTIR), hot stage polarized microscopy (HSPM) and scanning electron microscopy (SEM). Stability of the cocrystal was assessed by storing them at 40°C/75% RH for one month. Compared to PCA, the cocrystal displayed superior tableting performance. PCA-5NIP cocrystal showed a similar dissolution profile as compared to PCA and exhibited good stability. This study showed the utility of PCA-5NIP cocrystal for improving mechanical properties of PCA.


Biochimica et Biophysica Acta | 1994

Selective putrescine export is regulated by insulin and ornithine in Reuber H35 hepatoma cells

Leo Hawel; Raymond R. Tjandrawinata; Craig V. Byus

Cultured Reuber H35 rat hepatoma cells under highly viable serum-free conditions were found to selectively export putrescine from inside the cell into the culture medium, but not spermidine, spermine, or their acetylated derivatives. Even untreated cells, with very low intracellular putrescine levels, constitutively exported significant amounts of only putrescine for a 12 h period. Administration of the phorbol ester TPA (12-O-tetradecanoylphorbol 13-acetate) which markedly elevates ornithine decarboxylase (ODC), did not potentiate putrescine export over what was measured in the unstimulated cultures. However, addition of 1 mM ornithine to the cultures resulted in increased intracellular putrescine (maximum at 4 h) with a marked concomitant increase in putrescine export between 0 and 8 h, after which putrescine export again stopped. Treatment with 10(-7) M insulin yielded intracellular putrescine levels that remained elevated for 36 along with a continuous and more rapid export of putrescine over the same 36 h time period. When insulin and ornithine were administered together, even higher levels of intracellular putrescine and putrescine export were observed, with putrescine efflux proceeding over the 36 h time-course at the highest observed rates of 1.5 (0-12 h) and 1.0 (12-36 h) nmol/mg total protein per h. Exposure to DFMO, an inhibitor of ODC, depleted intracellular putrescine stores and effectively suppressed putrescine export. There was not a positive correlation between the time-dependent decreases in the intracellular putrescine concentrations and the respective alterations in the rate of putrescine export under a variety of conditions. Furthermore, the drug verapamil was capable of completely inhibiting putrescine export (IC50 approx. 1 microM) without any change in the level of intracellular putrescine. This data was not consistent with the involvement of simple diffusion of putrescine through the membrane as the major mechanism for putrescine export. The potential mechanisms involved in putrescine export and the role of this process in regulating intracellular polyamine levels, as well as, possible functions of extracellular putrescine are discussed.


principles and practice of constraint programming | 2008

Symptomatic treatment of acute tonsillo-pharyngitis patients with a combination of Nigella sativa and Phyllanthus niruri extract.

Dirjomuljono M; Kristyono I; Raymond R. Tjandrawinata; Dwi Nofiarny

Acute tonsillopharyngitis is characterized by tonsil or pharyngeal inflammation and mostly is a virus in origin; thus, treatment that covers both the inflammation and inadequate immune response against the pathogenic organism is needed. NSPN extract containing Nigella sativa and Phyllanthus niruri extracts has both antiinflammatory and immunomodulatory effects. A comparative, parallel, randomized, double-blind, placebo-controlled study with a treatment period of 7 days was conducted to examine clinical effectiveness of Nigella sativa and Phyllanthus niruri extract (NSPN extract). Of 200 enrolled patients, 186 patients completed the study, 12 patients withdrew and 2 patients were principally screened failure but inadvertently included. NSPN capsules, each containing 360 mg Nigella sativa and 50 mg Phyllanthus niruri extracts, were orally administered 3 times 1 capsule daily for 7 days. At Hour 5 or 6 of the first dosing of study medication, the sore throat assessed as swallowing pain and difficulty, was markedly alleviated in the NSPN group. In line with the significant alleviation of pain, from Days 0 to 2 of treatment, subjects in the NSPN group also needed significantly less escape âanalgesicâ therapy (paracetamol tablets) than those in the placebo group. At the end of treatment (Day 7), a significantly greater proportion of patients in the NSPN group than in the placebo group had their sore throat completely relieved. NSPN extract was also found to be safe and well tolerated in acute tonsillopharyngitis patients. This study proved significant benefits of NSPN extract in the treatment of acute tonsillopharyngitis as compared to placebo.


International Journal of General Medicine | 2011

Symptomatic treatment of premenstrual syndrome and/or primary dysmenorrhea with DLBS1442, a bioactive extract of Phaleria macrocarpa

Raymond R. Tjandrawinata; Dwi Nofiarny; Liana W Susanto; Prihatini Hendri; Audrey Clarissa

Background: DLBS1442, a proprietary and standardized semipolar bioactive extract of the fruit Phaleria macrocarpa, is preclinically proven to have anti-inflammatory properties. The current clinical study evaluated the efficacy and safety of DLBS1442 in alleviating symptoms of premenstrual syndrome and primary dysmenorrhea. Methods: This was an open study over four menstrual cycles (with two control cycles, followed by two treatment cycles). Women with premenstrual syndrome and/or primary dysmenorrhea, 18–40 years of age, and with a regular menstrual cycle were included in the study. In the treatment cycles, DLBS1442 extract was given as a 100 mg capsule two or three times daily (for those with mild and moderate-to-severe baseline abdominal pain, respectively), for an average of six days, ie, three days before until the end of the first three days of the menstrual period. Throughout all four study cycles, daily self-assessment of symptoms related to premenstrual syndrome was made by each subject using a visual analog scale (VAS). Data were descriptively analyzed and profiled in curves of VAS score versus time point evaluation starting from day 5 before menstruation to day 5 of menstruation. Results: Twenty-three subjects of mean age 27.35 ± 5.73 years were evaluable for the intention to treat analysis. Most subjects experienced the primary efficacy variable (abdominal pain), peaking on days 1–2 of the menstrual phase, with a mean VAS score of 36.8 ± 24.3 mm and 30.0 ± 29.6 mm, respectively, during control cycles. DLBS1442 markedly reduced VAS scores by 13.76 ± 28.27 mm (37.46%) and 13.28 ± 29.06 mm (44.28%), respectively. Other symptoms of premenstrual syndrome were also markedly alleviated by DLBS1442. Some mild adverse events were observed and resolved by the end of the study. Conclusion: This preliminary study indicates the effectiveness of DLBS1442 in alleviating primary dysmenorrhea and abdominal pain, as well as other symptoms related to premenstrual syndrome. DLBS1442 was safe and well tolerated in women with premenstrual syndrome and/or dysmenorrhea.


Cancer Biology & Therapy | 2010

Induction of cellular apoptosis in human breast cancer by DLBS1425, a Phaleria macrocarpa compound extract, via down-regulation of PI3-kinase/AKT pathway

Olivia Mayasari Tandrasasmita; Jason S. Lee; Sung Hee Baek; Raymond R. Tjandrawinata

Phaleria macrocarpa, also known as Mahkota dewa, is an Indonesian native plant that has been used as a remedy for many diseases. However, the molecular mechanism of Phaleria macrocarpa is still limited. In this study, we evaluate its molecular mechanism using a bioactivity-guided DLBS1425, an extract of Phaleria macrocarpa on MDA-MB-231 breast cancer cell line. DLBS1425 exhibited inhibition of proliferative, migratory and invasive potential of MDA-MB-231 in a dose-dependent manner, and significantly reduced phosphoinositide-3 (PI3)-kinase/protein kinase B (AKT) signalling by reducing PI3K transcript level and subsequent reduction in AKT phosphorylation. Further, it induced pro-apoptotic genes including BAX, BAD and PUMA and consequently induces cellular death signal by caspase-9 activation, promoting PARP cleavage and DNA fragmentation. Our results suggest that DLBS1425 is a potential anticancer agent which targets genes involved in both cell survival and apoptosis in MDA-MB-231 breast cancer cells.


Biochemical Pharmacology | 1994

Characterization of putrescine and cadaverine export in mammalian cells

Raymond R. Tjandrawinata; Leo Hawell; Craig V. Byus

We characterized the mechanism(s) involved in the efflux of putrescine/cadaverine from cultured mammalian cells using various pharmacological agents. Verapamil and quinine inhibited putrescine and cadaverine export in monocytic-leukemic RAW 264 and H35 hepatoma cells in a concentration-dependent manner with an IC50 in the micromolar range. Verapamil, which inhibits L-type calcium channels, inhibited putrescine export, regardless of whether calcium was present in the extracellular medium or not. Furthermore, the export of putrescine in the absence of verapamil did not appear to depend upon extracellular calcium. Neither intracellular calcium, external sodium, changes in intracellular pH nor phosphorylation affected the levels of putrescine export independently from changes in intracellular putrescine levels. The data suggest that verapamil and quinine inhibit putrescine/cadaverine efflux from the cell by binding directly to an integral membrane protein.

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Bambang Veriansyah

Korea Institute of Science and Technology

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Heni Rachmawati

Bandung Institute of Technology

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Stevanus Hiendrawan

Bandung Institute of Technology

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Debbie S. Retnoningrum

Bandung Institute of Technology

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Craig V. Byus

University of California

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