• Biomolecules & Therapeutics
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• v.19 no.4
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• pp.390-397
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• 2011

G protein-coupled receptor kinases (GRKs) and ${\beta}$-arrestins have been known as regulators of G protein-coupled receptors. However, it has been recently reported that GRKs and ${\beta}$-arrestins mediate receptor-mediated cellular responses in a G proteinin-dependent manner. In this scheme, GRKs work as a mediator or a scaffold protein. Among 7 members of the GRK family (GRK1-GRK7), GRK2 is the most extensively studied in vitro and in vivo. GRK2 is involved in cellular migration, insulin signaling, and cardiovascular disease. GRK6 in concert with ${\beta}$-arrestin 2 mediates chemoattractant-stimulated chemotaxis of T and B lymphocytes. GRK5 shuttles between the cytosol and nucleus, and regulates the activities of transcription factors. GRK3 and GRK4 do not seem to have striking effects on cellular responses other than receptor regulation. GRK1 and GRK7 play specific roles in regulation of rhodopsin function. In this review, these newly discovered functions of GRKs are briefly described.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1996.11a
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• pp.75-84
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• 1996

Platelets from a patient with a mild inherited bleeding disorder and abnormal platelet aggregation and secretion show reduced generation of inositol 1,4,5-trisphosphate (IP$_3$), mobilization of intracellular Ca$\^$2+/, and phosphorylation of pleckstrin in response to several G protein mediated agonists, suggesting a possible defect at the level of phospholipase C (PLC) activation. A procedure was developed that allows quantitation of platelet PLC isozymes. After fractionation of platelet extracts by high-performance liquid chromatography, seven, out often known PLC isoforms were detected by immunoblot analysis. The amount of these isoforms in normal platelets decreased in the order PLC-${\gamma}$2 > PLC-${\beta}$2 > PLC-${\beta}$3 > PLC-${\beta}$l > PLC-${\gamma}$ > PLC-$\delta$1 > PLC-${\beta}$4. Compared with normal platelets, platelets from the patient contained approximately one-third the amount of PLC-${\beta}$2, whereas PLC-${\beta}$4 was increased threefold. These results suggest that the impaired platelet function in the patient in response to multiple G protein mediated agonists is attributable to a deficiency of PLC-${\beta}$2. They document for the first time a specific PLC isozyme deficiency in human platelets and provide an unique opportunity to understand the role of different PLC isozymes in normal platelet function.

• The Korean Journal of Pesticide Science
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• v.8 no.2
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• pp.137-144
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• 2004

[ $\beta$ ]-Ketoacetoanilide chloride derivatives containing a substituent at 4 in phenyl group (para) reduced specifically the development of tomato late blight caused by Phytophthora infestans. Among $\beta$ketoacetoanilide chloride derivatives, five (KIST163, KIST170, KIST260, KIST263, and KIST267) were selected and tested for their protective, curative, systemic, persistent activities, and disease control efficacy against tomato late blight on adult plants. They exhibited a strong l-day protective activity and $EC_{50}$ of KIST163 and KIST170 were 21.9 and $14.5{\mu}g/mL$, respectively. However, they had little curative and systemic activities. Good persistence of KIST163 and KIST170 on tomato plants were observed against P. infestans; both KIST163 and KIST170 at $100{\mu}g/mL$ showed control values more than 75% in a 7-day protective applications. In addition, the two chemicals effectively controlled the occurrence of P. infestans on adult tomato plants. These results indicate that five $\beta$-ketoacetoanilide chloride derivatives are foliar fungicides with a preventive action and KIST163 and KIST170 have a potential for the control of tomato late blight in the fields.

• Journal of applied mathematics & informatics
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• v.26 no.1_2
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• pp.275-282
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• 2008

Our aim in this paper is to investigate the global attractivity of the recursive sequence $x_{n+1}$ = $\frac{\alpha-{\beta}x_{n-1}}{\gamma+g(x_n)}$ under specified conditions. We show that the positive (or zero for $\alpha$ = 0) equilibrium point of the equation is a global attractor with a basin that depends on certain conditions posed on the coefficients and the function g(x).

• Clinical and Experimental Pediatrics
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• v.50 no.4
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• pp.369-375
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• 2007

Purpose : There have been numerous researches on urine ${\beta}_2$-microglobulin (${\beta}_2$-M) concerned with primary nephrotic syndrome and other glomerular diseases, but not much has been done in relation to pediatric age groups. Thus, our hospital decided to study the relations between the analysis of the test results we have conducted on pediatric patients and renal functions. Methods : Retrospective data analysis was done to 102 patients of ages 0 to 4 with renal diseases with symptoms such as hematuria, edema, and proteinuria who were admitted to Chung-Ang Yongsan Hospital and who participated in 24-hour urine and urine ${\beta}_2$-M excretion test between January of 2003 and January of 2006. Each disease was differentiated as independent variables, and the statistical difference of the results of urine ${\beta}_2$-M excretion of several groups of renal diseases was analyzed with student T-test by using test results as dependent variables. Results : Levels of urine ${\beta}_2$-M excretion of the 102 patients were as follows : 52 had primary nephrotic syndrome [MCNS (n=45, $72{\pm}45{\mu}g/g$ creatinine, ${\mu}g/g-Cr$), MPGN (n=3, $154{\pm}415{\mu}g/g-Cr$), FSGS (n=4, $188{\pm}46{\mu}g/-Cr$], six had APSGN ($93{\pm}404{\mu}g/g-Cr$), seven had IgA nephropathy ($3,414{\pm}106{\mu}g/g-Cr$), 9 had APN ($742{\pm}160{\mu}g/g-Cr$), 16 had cystitis ($179{\pm}168{\mu}g/g-Cr$), and 12 had HSP nephritis ($109{\pm}898{\mu}g/g-Cr$). IgA nephropathy (P<0.05) and APN (P<0.05) were significantly higher than in other renal diseases. Among primary nephrotic syndrome, FSGS with higher results of ${\beta}_2$-microglobulin test had longer treatment period (P<0.01) when compared to the lower groups, but no significant differences in Ccr, BUN, or Cr were observed. Conclusion : IgA nephropathy and APN groups showed significantly higher level of ${\beta}_2$-M excretion value than other groups. Although ${\beta}_2$-microglobulin value is not appropriate as an indicator of general renal function and pathology, it seems to be sufficient in the differential diagnosis of the UTI and in the prediction of the treat-ment period of nephrotic syndrome patients.

• Biomolecules & Therapeutics
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• v.24 no.5
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• pp.517-522
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• 2016

${\beta}$-Arrestins are one of the protein families that interact with G protein-coupled receptors (GPCRs). The roles of ${\beta}$-arrestins are multifaceted, as they mediate different processes including receptor desensitization, endocytosis, and G protein-independent signaling. Thus, determining the GPCR regions involved in the interactions with ${\beta}$-arrestins would be a preliminary step in understanding the molecular mechanisms involved in the selective direction of each function. In the current study, we determined the roles of the N-terminus, intracellular loops, and C-terminal tail of a representative GPCR in the interaction with ${\beta}$-arrestin2. For this, we employed dopamine $D_2$ and $D_3$ receptors ($D_2R$ and $D_3R$, respectively), since they display distinct agonist-induced interactions with ${\beta}$-arrestins. Our results showed that the second and third intracellular loops of $D_2R$ are involved in the agonist-induced translocation of ${\beta}$-arrestins toward plasma membranes. In contrast, the N- and C-termini of $D_2R$ exerted negative effects on the basal interaction with ${\beta}$-arrestins.

• Journal of applied mathematics & informatics
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• v.29 no.5_6
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• pp.1421-1433
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• 2011

In this paper, using a fixed point approach, the generalized Hyeres-Ulam stability of the following quadratic functional equation $f(x+y+z)+f(x+{\sigma}(y))+f(y+{\sigma}(z))+f(x+{\sigma}(z))=3(f(x)+f(y)+f(z))$ will be studied, where f is a function from abelian group G into a quasi-${\beta}$-normed space and ${\sigma}$ is an involution on the group G. Next, we consider its pexiderized equation of the form $f(x+y+z)+f(x+{\sigma}(y))+f(y+{\sigma}(z))+f(x+{\sigma}(z))=g(x)+g(y)+g(z)$ and its generalized Hyeres-Ulam stability.

• Korean Journal of Food Science and Technology
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• v.28 no.4
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• pp.689-695
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• 1996

In order to prove physiological function of ${\beta}-Glucan$ isolated from barley flour by enzymatic method, in vitro experiments simulating the passive membrane transport of gastrointestinal tract were carried out using dialysis membrane. The yield of ${\beta}-Glucan$ from barley flour was $6.2{\%}$ and its constituents were determined to give $81.6{\%}$ total dietary fiber, $72.9{\%}$ soluble dietary fiber, $8.7{\%}$ insoluble dietary fiber, $8.5{\%}$ moisture, $2.5{\%}$ protein and $7.4{\%}$ ash. The water holding capacity of the ${\beta}-Glucan$ preparation was 6 g water/g dry material. The glucose retardation index after 30 minute dialysis was $13.5{\%}$ in the presence of $3{\%}$ ${\beta}-Glucan$. As the dialysis period became longer, the retarding effect toward glucose absorption decreased and the effect was close to zero after 2 hour dialysis. The bile acid retardation index after 30 minute dialysis was 3, 12 and $18{\%}$ in the presence of 1, 3 and $5{\%}$ ${\beta}-Glucan$, respectively. The effect was higher than the glucose retardation index and decreased as the dialysis time elapsed.

• Bulletin of the Korean Mathematical Society
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• v.42 no.3
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• pp.563-569
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• 2005

In [2], Jahangiri studied the harmonic starlike functions of order $\alpha$, and he defined the class T$_{H}$($\alpha$) consisting of functions J = h + $\bar{g}$ where hand g are the analytic and the co-analytic part of the function f, respectively. In this paper, we introduce the class T$_{H}$($\alpha$, $\beta$) of analytic functions and prove various coefficient inequalities, growth and distortion theorems, radius of convexity for the function h, if the function J belongs to the classes T$_{H}$($\alpha$) and T$_{H}$($\alpha$, $\beta$).

• Preventive Nutrition and Food Science
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• v.14 no.2
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• pp.102-108
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• 2009

The comparative immunomodulatory effects of ${\beta}$-glucans isolated from mushroom fungi (Coriolus versicol), yeast (Saccharomyces cerevisiae) and bacteria (Agrobacterium) on the major functions of macrophages were evaluated. As parameters of macrophage functions, we examined tumoricidal activity, phagocytosis, nitric oxide (NO) production, and the induction of inducible NO synthetase (iNOS) in RAW264.7 cells, following treatments with ${\beta}$-glucans from the three different sources. The results indicated that all ${\beta}$-glucan treatments significantly induced tumoricidal activity in the RAW264.7 cells, with a remarkable effect shown by the beta-glucan from Agrobacterium at a concentration of $10{\mu}g/mL$. There was also a significant increase in iNOS-NO system activity in macrophages treated with ${\beta}$-glucans extracted from yeast; however, iNOS-NO system activity was not markedly changed by the treatment of ${\beta}$-glucans from C. versicolor mushroom fungi or Agrobacterium. Furthermore, the ${\beta}$-glucans from C. versicolor had a significant phagocytotic effect at concentrations of 1, 10, and $100{\mu}g/mL$. Taken together, the present data suggest that these ${\beta}$-glucans, isolated from three different sources, have different effects on macrophage function, and therefore, may have different clinical uses in different for various types of diseases.