iwan setiawan - Academia.edu (original) (raw)

Papers by iwan setiawan

International Journal of Applied Business Research

Islamic bank can play a role in improving the welfare of the community. Through the intermediary ... more Islamic bank can play a role in improving the welfare of the community. Through the intermediary function, Islamic banks raise funds deposits and channel financing for productive purposes. The purpose of this study is to examine the role of Islamic bank financing to increase economic productivity and job creation. This study uses simultaneous panel estimation technique with Two Stage Least Square (TSLS) method, using secondary data from 2005-2016. The results of this study reveal that the financing of Islamic banks play a role in increasing economic activity and employment, the role of Islamic banks finance large from the role of conventional bank credit, although the contribution is not too large. Regression result per sector of economy indicates that financing of syariah bank give positive role to increase economic activity in each. The role of financing for job creation by economic sector shows different results. Most Shariah banking financing in the economic sector (7 sectors) p...

Molecular Reproduction and Development, 2004

Transgenic mice targeted for the c-ros gene, which are fertile when heterozygous (HET), but infer... more Transgenic mice targeted for the c-ros gene, which are fertile when heterozygous (HET), but infertile when homozygous (knockout, KO) and associated with failure in pubertal differentiation of the epididymal initial segment, provide a model for studying the role of the epididymal luminal environment in sperm development. Luminal fluid from the cauda epididymidis was measured by both ion-selective microelectrodes and pH strips to be 0.3 pH units higher in the KO than HET. Of the genes responsible for luminal acidification, expression of mRNA of vacuolar H+-ATPase was found in all epididymal regions, but with no difference between KO and HET. Immunohistochemistry showed its presence in epithelial apical cells and clear cells. The Na+–hydrogen exchanger NHE2 was expressed at mRNA and protein levels in the caput but only marginally detectable if at all in the distal epididymis. This was compensated for by NHE3 which was expressed strongest in the cauda region, in agreement with immunohistochemical staining. Quantification of Western blot data revealed slight, but significant, decreases of NHE2 in the caput and of NHE3 in the cauda in the KO mice. The increase in luminal fluid pH in the KO mice could also be contributed to by other epithelial regulating factors including the Na+-dependent glutamate transporter EAAC1 formerly reported to be down regulated in the KO. Mol. Reprod. Dev. 68: 159–168, 2004. © 2004 Wiley-Liss, Inc.

Comparative Biochemistry and Physiology A-molecular & Integrative Physiology, 2001

Cellular Physiology and Biochemistry, 2004

The epithelial Ca2&am... more The epithelial Ca2+ channel TRPV5 (ECaC1) plays a key role in renal and intestinal Ca2+ (re)absorption and is thus regulated by 1,25(OH) 2D3. The present study aims to explore whether TRPV5 is regulated by the serum and glucocorticoid inducible kinase SGK1, a kinase transcriptionally upregulated by 1,25(OH) 2D3. To this end cRNA encoding TRPV5 has been injected into Xenopus oocytes

Journal of Physiology-london, 2002

Volume regulation by spermatozoa has been demonstrated to be crucial in both mice and men for tra... more Volume regulation by spermatozoa has been demonstrated to be crucial in both mice and men for transport in the female tract. In order to determine the nature of osmolytes used by spermatozoa, they were released from the cauda epididymis of fertile c-ros heterozygous mice into incubation medium of uterine osmolality (representing an osmotic challenge), containing increasing concentrations of compounds that are major epididymal fluid components and known osmolytes in somatic cells. This should nullify the concentration gradients for osmolytes that mediate volume regulation, prevent osmolyte efflux, and lead to swelling. Of the osmolytes tested, K ϩ caused the most rapid and extensive volume increases; glutamate, taurine, L-carnitine, and myo-inositol also were effective, but glycerophosphocholine was not. Such effects were not observed in cauda sperm from the infertile knockout mice, demonstrating a defect in normal volume regulation. K ϩ concentrations in cauda epididymal fluid were 21 mM higher in the knockout than the heterozygous mice, but no differences were found in caudal fluid glutamate, carnitine, or myo-inositol. The carnitine content of cauda sperm from knockout males was not different from that of fertile males, but lower amounts of glutamate and inositol were found that could explain the poor volume regulation. In heterozygous mice, cauda but not caput sperm responded to the K ϩ channel blocker quinine by swelling, demonstrating development of volume regulation during epididymal transit, whereas knockout cauda sperm showed no response, as with the osmolytes. Major epididymal secretions could serve as osmolytes in murine spermatozoa for volume regulation in response to physiological osmotic challenge in the normal fertile mice; the reduced sperm content of inositol and glutamate in the c-ros knockout mice might reflect maturational abnormalities in volume regulation.

Comparative Biochemistry and Physiology A-molecular & Integrative Physiology, 2000

Regulation of the epithelial brush border Na/H exchanger (NHE) NHE3 has been studied in intact ti... more Regulation of the epithelial brush border Na/H exchanger (NHE) NHE3 has been studied in intact tissue, polarized epithelial cells and when expressed in a fibroblast model, PS I20 cells. In intact ileum, agents which elevate CAMP inhibit NHE3, including secretin, VIP, and cholera toxin; while agents which elevate cGMP also inhibit NHE3. including guanylin and heat stable E. coli enterotoxin.

Kidney & Blood Pressure Research, 2002

Expression of the constitutively active form of serum and glucocorticoid-dependent kinase ((S422D... more Expression of the constitutively active form of serum and glucocorticoid-dependent kinase ((S422D)SGK1) in Xenopus oocytes has recently been shown to upregulate endogenous Na(+)/K(+)-ATPase activity, an effect presumably participating in the regulation of cellular K(+) uptake and transepithelial Na(+) transport. SGK1 and the two isoforms SGK2 and SGK3 are stimulated by insulin and insulin-like growth factor-1 (IGF-1), which have been shown to enhance Na(+)/K(+)-ATPase activity in a variety of cells. The present experiments have been performed to elucidate whether or not wild-type SGK1, SGK2 and SGK3 are similar to (S422D)SGK1 in being effective regulators of Na(+)/K(+)-ATPase. To this end, dual-electrode voltage clamp experiments were performed in Xenopus oocytes injected either with water or with mRNA of constitutively active (S422D)SGK1 and wild-type SGK1, SGK2 or SGK3. Na(+)/K(+)-ATPase activity was estimated from the outward-directed current created by readdition of extracellular K(+) in the presence of K(+) channel blocker Ba(2+) following a 10-min exposure to K(+)-free extracellular fluid. The outward-directed current was fully abolished by incubation with 1 mM ouabain and was significantly larger in oocytes expressing (S422D)SGK1, SGK1, SGK2 or SGK3, as compared to those injected with water. The stimulating effect of SGK1 on the Xenopus oocyte Na(+)/K(+)-ATPase is mimicked by the isoforms SGK2 and SGK3. Thus, all three kinases may participate in the regulation of Na(+)/K(+)-ATPase activity by hormones such as insulin and IGF-1.

Cellular Physiology and Biochemistry, 2000

The oocytes of the South African clawed frog X. laevis are widely used for the expression of hete... more The oocytes of the South African clawed frog X. laevis are widely used for the expression of heterologous proteins. The functional characterization of membrane proteins in particular has significantly profited from the use of this expression system. Heterologous cRNA can easily be ...

Pflugers Archiv-european Journal of Physiology, 2001

Extracellular pH has been shown previously to influence transport via type-II Na+/phosphate (NaPi... more Extracellular pH has been shown previously to influence transport via type-II Na+/phosphate (NaPi) transporters by modifying the affinity of the carrier for Na+ and by altering the availability of divalent and monovalent phosphate. As the transport of monovalent phosphate would be expected to acidify, and that of divalent phosphate to alkalinize the cell interior, the effect of phosphate transport on cytosolic pH was studied using ion selective microelectrodes in Xenopus oocytes expressing NaPi-3 or NaPi-5. At an alkaline extracellular pH (pHe) of 8.0, addition of phosphate elicited a strong inward current, depolarization of the cell membrane and cytosolic alkalinization. At pHe 6.0 the phosphate-induced inward current and depolarization were reduced and the alkalinization completely abolished. In conclusion, at alkaline pHe phosphate transport is enhanced and the transport of divalent phosphate prevails. At pHe 6.0, phosphate transport is attenuated and is accomplished by transport of both divalent and monovalent phosphate.

Journal of The American Society of Nephrology, 2002

Mineralocorticoids stimulate Na ϩ reabsorption and

Nephron, 2002

rBAT, together with its subunit b(0,+) AT mediates the hetero- and homoexchange of neutral and di... more rBAT, together with its subunit b(0,+) AT mediates the hetero- and homoexchange of neutral and dibasic amino acids. Since the heteroexchange of dibasic amino acids against neutral amino acids is coupled to net transport of positive charge, this transport is electrogenic. Extracellular addition of histidine could create an inward or an outward current depending on extracellular pH (pH(e)) and cell membrane potential. It has been concluded that histidine may be transported in both its protonated and its neutral form. In this study measurements of cytosolic pH (pH(i)) were performed to test this hypothesis. As a result, addition of protonated histidine at acidic pH(e) to Xenopus oocytes expressing rBAT creates an inward current which is paralleled by cytosolic acidification. Both can be reduced by increase of pH(e). At alkaline pH(e) and simultaneous depolarization of the cell membrane the effect of histidine on pH(i) is virtually abolished. The neutral amino acid leucine does not alter cytosolic pH at neither pH 6.0 nor at pH 8.0. In conclusion, histidine can be transported in either its neutral or its protonated form. Transport of the protonated form is facilitated by extracellular acidification and hyperpolarization of the cell membrane.

Pflugers Archiv-european Journal of Physiology, 2001

Transfer of glutamine between astrocytes and neurons is an essential part of the glutamate–glutam... more Transfer of glutamine between astrocytes and neurons is an essential part of the glutamate–glutamine cycle in the brain. Here we have investigated how the neural glutamine transporter (rATA1/GlnT) works. Rat ATA1 was expressed in Xenopus laevis oocytes and examined using two-electrode voltage-clamp recordings, ion-sensitive microelectrodes and tracer flux experiments. Glutamine transport via rATA1 was electrogenic and caused inward currents that did not reverse at positive holding potentials. Currents were induced by a variety of neutral amino acids in the following relative order Ala>Ser/Gln/Asn/His/Cys/Met >MeAIB/Gly>Thr/Pro/Tyr/Val, where MeAIB is the amino acid analogue N-methylaminoisobutyric acid. The uptake of glutamine and the corresponding currents depended on Na+ and pH. Hill-coefficient and flux studies with 22NaCl indicated a cotransport stoichiometry 1 Na+ per transport cycle. The transporter also showed uncoupled Na+ transport, particularly when alanine was used as the substrate. Although substrate uptake increased strongly with increasing pH, no change of intracellular pH was observed during transport. A decrease of the intracellular pH similarly inhibited glutamine transport via ATA1, suggesting that the pH dependence was an allosteric effect on the transporter.

Biochemical and Biophysical Research Communications, 2003

The amino acid transporter SN1 with substrate specificity identical to the amino acid transport s... more The amino acid transporter SN1 with substrate specificity identical to the amino acid transport system N is expressed mainly in astrocytes and hepatocytes where it accomplishes Na þ -coupled glutamine uptake and efflux. To characterize properties and regulation of SN1, substrate-induced currents and/or radioactive glutamine uptake were determined in Xenopus oocytes injected with cRNA encoding SN1, the ubiquitin ligase Nedd4-2, and/or the constitutively active serum and glucocorticoid inducible kinase S422D SGK1, its isoform SGK3, and the constitutively active protein kinase B T308D;S473D PKB. The substrate-induced currents were enhanced by increasing glutamine and/or Na þ concentrations, hyperpolarization, and alkalinization (pH 8.0). They were inhibited by acidification (pH 6.0). Coexpression of Nedd4-2 downregulated SN1-mediated transport, an effect reversed by coexpression of S422D SGK1, SGK3, and T308D;S473D PKB. It is concluded that SN1 is a target for the ubiquitin ligase Nedd4-2, which is inactivated by the serum and glucocorticoid inducible kinase SGK1, its isoform SGK3, and protein kinase B.

International Journal of Applied Business Research

Islamic bank can play a role in improving the welfare of the community. Through the intermediary ... more Islamic bank can play a role in improving the welfare of the community. Through the intermediary function, Islamic banks raise funds deposits and channel financing for productive purposes. The purpose of this study is to examine the role of Islamic bank financing to increase economic productivity and job creation. This study uses simultaneous panel estimation technique with Two Stage Least Square (TSLS) method, using secondary data from 2005-2016. The results of this study reveal that the financing of Islamic banks play a role in increasing economic activity and employment, the role of Islamic banks finance large from the role of conventional bank credit, although the contribution is not too large. Regression result per sector of economy indicates that financing of syariah bank give positive role to increase economic activity in each. The role of financing for job creation by economic sector shows different results. Most Shariah banking financing in the economic sector (7 sectors) p...

Molecular Reproduction and Development, 2004

Transgenic mice targeted for the c-ros gene, which are fertile when heterozygous (HET), but infer... more Transgenic mice targeted for the c-ros gene, which are fertile when heterozygous (HET), but infertile when homozygous (knockout, KO) and associated with failure in pubertal differentiation of the epididymal initial segment, provide a model for studying the role of the epididymal luminal environment in sperm development. Luminal fluid from the cauda epididymidis was measured by both ion-selective microelectrodes and pH strips to be 0.3 pH units higher in the KO than HET. Of the genes responsible for luminal acidification, expression of mRNA of vacuolar H+-ATPase was found in all epididymal regions, but with no difference between KO and HET. Immunohistochemistry showed its presence in epithelial apical cells and clear cells. The Na+–hydrogen exchanger NHE2 was expressed at mRNA and protein levels in the caput but only marginally detectable if at all in the distal epididymis. This was compensated for by NHE3 which was expressed strongest in the cauda region, in agreement with immunohistochemical staining. Quantification of Western blot data revealed slight, but significant, decreases of NHE2 in the caput and of NHE3 in the cauda in the KO mice. The increase in luminal fluid pH in the KO mice could also be contributed to by other epithelial regulating factors including the Na+-dependent glutamate transporter EAAC1 formerly reported to be down regulated in the KO. Mol. Reprod. Dev. 68: 159–168, 2004. © 2004 Wiley-Liss, Inc.

Comparative Biochemistry and Physiology A-molecular & Integrative Physiology, 2001

Cellular Physiology and Biochemistry, 2004

The epithelial Ca2&am... more The epithelial Ca2+ channel TRPV5 (ECaC1) plays a key role in renal and intestinal Ca2+ (re)absorption and is thus regulated by 1,25(OH) 2D3. The present study aims to explore whether TRPV5 is regulated by the serum and glucocorticoid inducible kinase SGK1, a kinase transcriptionally upregulated by 1,25(OH) 2D3. To this end cRNA encoding TRPV5 has been injected into Xenopus oocytes

Journal of Physiology-london, 2002

Volume regulation by spermatozoa has been demonstrated to be crucial in both mice and men for tra... more Volume regulation by spermatozoa has been demonstrated to be crucial in both mice and men for transport in the female tract. In order to determine the nature of osmolytes used by spermatozoa, they were released from the cauda epididymis of fertile c-ros heterozygous mice into incubation medium of uterine osmolality (representing an osmotic challenge), containing increasing concentrations of compounds that are major epididymal fluid components and known osmolytes in somatic cells. This should nullify the concentration gradients for osmolytes that mediate volume regulation, prevent osmolyte efflux, and lead to swelling. Of the osmolytes tested, K ϩ caused the most rapid and extensive volume increases; glutamate, taurine, L-carnitine, and myo-inositol also were effective, but glycerophosphocholine was not. Such effects were not observed in cauda sperm from the infertile knockout mice, demonstrating a defect in normal volume regulation. K ϩ concentrations in cauda epididymal fluid were 21 mM higher in the knockout than the heterozygous mice, but no differences were found in caudal fluid glutamate, carnitine, or myo-inositol. The carnitine content of cauda sperm from knockout males was not different from that of fertile males, but lower amounts of glutamate and inositol were found that could explain the poor volume regulation. In heterozygous mice, cauda but not caput sperm responded to the K ϩ channel blocker quinine by swelling, demonstrating development of volume regulation during epididymal transit, whereas knockout cauda sperm showed no response, as with the osmolytes. Major epididymal secretions could serve as osmolytes in murine spermatozoa for volume regulation in response to physiological osmotic challenge in the normal fertile mice; the reduced sperm content of inositol and glutamate in the c-ros knockout mice might reflect maturational abnormalities in volume regulation.

Comparative Biochemistry and Physiology A-molecular & Integrative Physiology, 2000

Regulation of the epithelial brush border Na/H exchanger (NHE) NHE3 has been studied in intact ti... more Regulation of the epithelial brush border Na/H exchanger (NHE) NHE3 has been studied in intact tissue, polarized epithelial cells and when expressed in a fibroblast model, PS I20 cells. In intact ileum, agents which elevate CAMP inhibit NHE3, including secretin, VIP, and cholera toxin; while agents which elevate cGMP also inhibit NHE3. including guanylin and heat stable E. coli enterotoxin.

Kidney & Blood Pressure Research, 2002

Expression of the constitutively active form of serum and glucocorticoid-dependent kinase ((S422D... more Expression of the constitutively active form of serum and glucocorticoid-dependent kinase ((S422D)SGK1) in Xenopus oocytes has recently been shown to upregulate endogenous Na(+)/K(+)-ATPase activity, an effect presumably participating in the regulation of cellular K(+) uptake and transepithelial Na(+) transport. SGK1 and the two isoforms SGK2 and SGK3 are stimulated by insulin and insulin-like growth factor-1 (IGF-1), which have been shown to enhance Na(+)/K(+)-ATPase activity in a variety of cells. The present experiments have been performed to elucidate whether or not wild-type SGK1, SGK2 and SGK3 are similar to (S422D)SGK1 in being effective regulators of Na(+)/K(+)-ATPase. To this end, dual-electrode voltage clamp experiments were performed in Xenopus oocytes injected either with water or with mRNA of constitutively active (S422D)SGK1 and wild-type SGK1, SGK2 or SGK3. Na(+)/K(+)-ATPase activity was estimated from the outward-directed current created by readdition of extracellular K(+) in the presence of K(+) channel blocker Ba(2+) following a 10-min exposure to K(+)-free extracellular fluid. The outward-directed current was fully abolished by incubation with 1 mM ouabain and was significantly larger in oocytes expressing (S422D)SGK1, SGK1, SGK2 or SGK3, as compared to those injected with water. The stimulating effect of SGK1 on the Xenopus oocyte Na(+)/K(+)-ATPase is mimicked by the isoforms SGK2 and SGK3. Thus, all three kinases may participate in the regulation of Na(+)/K(+)-ATPase activity by hormones such as insulin and IGF-1.

Cellular Physiology and Biochemistry, 2000

The oocytes of the South African clawed frog X. laevis are widely used for the expression of hete... more The oocytes of the South African clawed frog X. laevis are widely used for the expression of heterologous proteins. The functional characterization of membrane proteins in particular has significantly profited from the use of this expression system. Heterologous cRNA can easily be ...

Pflugers Archiv-european Journal of Physiology, 2001

Extracellular pH has been shown previously to influence transport via type-II Na+/phosphate (NaPi... more Extracellular pH has been shown previously to influence transport via type-II Na+/phosphate (NaPi) transporters by modifying the affinity of the carrier for Na+ and by altering the availability of divalent and monovalent phosphate. As the transport of monovalent phosphate would be expected to acidify, and that of divalent phosphate to alkalinize the cell interior, the effect of phosphate transport on cytosolic pH was studied using ion selective microelectrodes in Xenopus oocytes expressing NaPi-3 or NaPi-5. At an alkaline extracellular pH (pHe) of 8.0, addition of phosphate elicited a strong inward current, depolarization of the cell membrane and cytosolic alkalinization. At pHe 6.0 the phosphate-induced inward current and depolarization were reduced and the alkalinization completely abolished. In conclusion, at alkaline pHe phosphate transport is enhanced and the transport of divalent phosphate prevails. At pHe 6.0, phosphate transport is attenuated and is accomplished by transport of both divalent and monovalent phosphate.

Journal of The American Society of Nephrology, 2002

Mineralocorticoids stimulate Na ϩ reabsorption and

Nephron, 2002

rBAT, together with its subunit b(0,+) AT mediates the hetero- and homoexchange of neutral and di... more rBAT, together with its subunit b(0,+) AT mediates the hetero- and homoexchange of neutral and dibasic amino acids. Since the heteroexchange of dibasic amino acids against neutral amino acids is coupled to net transport of positive charge, this transport is electrogenic. Extracellular addition of histidine could create an inward or an outward current depending on extracellular pH (pH(e)) and cell membrane potential. It has been concluded that histidine may be transported in both its protonated and its neutral form. In this study measurements of cytosolic pH (pH(i)) were performed to test this hypothesis. As a result, addition of protonated histidine at acidic pH(e) to Xenopus oocytes expressing rBAT creates an inward current which is paralleled by cytosolic acidification. Both can be reduced by increase of pH(e). At alkaline pH(e) and simultaneous depolarization of the cell membrane the effect of histidine on pH(i) is virtually abolished. The neutral amino acid leucine does not alter cytosolic pH at neither pH 6.0 nor at pH 8.0. In conclusion, histidine can be transported in either its neutral or its protonated form. Transport of the protonated form is facilitated by extracellular acidification and hyperpolarization of the cell membrane.

Pflugers Archiv-european Journal of Physiology, 2001

Transfer of glutamine between astrocytes and neurons is an essential part of the glutamate–glutam... more Transfer of glutamine between astrocytes and neurons is an essential part of the glutamate–glutamine cycle in the brain. Here we have investigated how the neural glutamine transporter (rATA1/GlnT) works. Rat ATA1 was expressed in Xenopus laevis oocytes and examined using two-electrode voltage-clamp recordings, ion-sensitive microelectrodes and tracer flux experiments. Glutamine transport via rATA1 was electrogenic and caused inward currents that did not reverse at positive holding potentials. Currents were induced by a variety of neutral amino acids in the following relative order Ala>Ser/Gln/Asn/His/Cys/Met >MeAIB/Gly>Thr/Pro/Tyr/Val, where MeAIB is the amino acid analogue N-methylaminoisobutyric acid. The uptake of glutamine and the corresponding currents depended on Na+ and pH. Hill-coefficient and flux studies with 22NaCl indicated a cotransport stoichiometry 1 Na+ per transport cycle. The transporter also showed uncoupled Na+ transport, particularly when alanine was used as the substrate. Although substrate uptake increased strongly with increasing pH, no change of intracellular pH was observed during transport. A decrease of the intracellular pH similarly inhibited glutamine transport via ATA1, suggesting that the pH dependence was an allosteric effect on the transporter.

Biochemical and Biophysical Research Communications, 2003

The amino acid transporter SN1 with substrate specificity identical to the amino acid transport s... more The amino acid transporter SN1 with substrate specificity identical to the amino acid transport system N is expressed mainly in astrocytes and hepatocytes where it accomplishes Na þ -coupled glutamine uptake and efflux. To characterize properties and regulation of SN1, substrate-induced currents and/or radioactive glutamine uptake were determined in Xenopus oocytes injected with cRNA encoding SN1, the ubiquitin ligase Nedd4-2, and/or the constitutively active serum and glucocorticoid inducible kinase S422D SGK1, its isoform SGK3, and the constitutively active protein kinase B T308D;S473D PKB. The substrate-induced currents were enhanced by increasing glutamine and/or Na þ concentrations, hyperpolarization, and alkalinization (pH 8.0). They were inhibited by acidification (pH 6.0). Coexpression of Nedd4-2 downregulated SN1-mediated transport, an effect reversed by coexpression of S422D SGK1, SGK3, and T308D;S473D PKB. It is concluded that SN1 is a target for the ubiquitin ligase Nedd4-2, which is inactivated by the serum and glucocorticoid inducible kinase SGK1, its isoform SGK3, and protein kinase B.