• IMMUNE NETWORK
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• v.2 no.2
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• pp.72-78
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• 2002

Background: The precise mechanism by which CTLA-4 regulates T cell immune responses is still not fully understood. Previously we proposed that CTLA-4 could downregulate T cell function by modulating a signaling cascade initiated from the T cell receptor complex. The evidence for this notion comes from our findings that CTLA-4 associated with the T cell receptor zeta (TCR zeta) chain, and hence regulated TCR zeta phosphorylation by co-associated SHP-2 tyrosine phosphatase (1). In this report, we investigated whether any other signaling molecules could be involved in the CTLA-4 signaling pathway. Methods: We have taken biochemical approaches, such as immunoprecipitation followed by autoradiography or immunoblotting, to identify the molecules associated with CTLA-4. To perform these assays, we used activated primary T cells and ectopically transfected 293 cells. Various truncation mutants of CTLA-4 were used to map the interaction site on CTLA-4. Results: We found that in addition to TCR zeta and SHP-2, a recently cloned small adaptor molecule, SAP (SLAM-associated protein), was also able to associate with CTLA-4. We identified the domain of SAP association in CTLA-4 being a motif involving GVYVKM. This motif has been previously found to bind SHP-2 through its phosphorylated tyrosine interaction with SH-2 domain of SHP-2. Indeed, co-expression of SAP and SHP-2 reduced their binding to CTLA-4 significantly, suggesting that SAP and SHP-2 compete for the common binding site, GVYVKM. Thus, by blocking SHP-2 recruitment SAP could function as a negative regulator of CTLA-4. Conclusion: Taken together, our data suggest the existence of complicate signaling cascade in regulating CTLA-4 function, and further provide evidence that SAP can act either as a positive or negative regulator depending on the nature of the associating receptors.

• Korean Journal of Agricultural Science
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• v.45 no.3
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• pp.485-492
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• 2018

Two experiments were conducted to investigate the effect of feeding a diet supplemented with swine hair protein (SHP) on the nutrient digestibility of Korean native chickens and their egg production as well as on egg quality. In experiment 1, twenty roosters of the Hanhyup-3 strain were assigned to an individual cage to give 10 replicates per treatment (i.e., 0 and 10% of SHP), and the nutrient digestibility in response to the SHP supplementation was measured. In experiment 2, fifty-four layers of the Hy-Line strain were assigned to an individual cage to give 27 replicates per treatment (i.e., 0 and 10% of SHP), and egg production and egg quality were measured. In experiment 1, no significant difference (p > 0.05) was found in the digestibility of crude protein, crude fat, nitrogen-free extract (NFE), and crude fiber in response to the diet supplemented with SHP. In experiment 2, although no significant difference (p > 0.05) was found with the dietary treatments, the 10% SHP supplemented diet decreased (p < 0.05) the feed intake of laying hens. However, the SHP supplemented diet did not affect (p > 0.05) the laying rate, egg weight and feed conversion ratio of those fed the diet. Eggshell thickness and yolk color decreased (p < 0.05); however, eggshell strength, eggshell color, albumen height and Haugh units increased (p < 0.05) by feeding layers a diet supplemented with SHP. In conclusion, the results suggest that 10% SHP supplemented in a poultry diet could be a useful protein source.

• Journal of Pharmacopuncture
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• v.11 no.1
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• pp.71-82
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• 2008

Objectives : The purpose of this study is to investigate the effects of Spirodelae Herba pharmacopuncture(SHP) on the adipogenesis in 3T3 cells, lipolysis in rat epididymal adipocytes and histological changes in porcine adipose tissue. Methods : Inhibition of preadipocyte differentiation and/or stimulation of lipolysis play important roles in reducing obesity. 3T3 preadipocytes were differentiated with adipogenic reagents by incubating for 3 days in the absence or presence of SHP ranging from 0.01 to $1.0mg/m{\ell}$. The effect of SHP on adipogenesis was examined by measuring glycerol-3-phosphate dehydrogenase(GPDH) activity and by Oil Red O staining. Mature adipocytes from rat epididymal fat pad was incubated with SHP ranging from 0.01 to $1.0mg/m{\ell}$ for 3 days. The effect of SHP on lipolysis was examined by measuring free glycerol released. Fat tissue from porcine skin was injected with SHP ranging from 0.1 to $10.0mg/m{\ell}$ to examine the effect of SHP onhistological changes under light microscopy. Results : Following results were obtained from the preadipocyte proliferation and lipolysis adipocyte and histologic investigation of fat tissue 1. SHP showed the effect of decreased preadipocyte proliferation on the high dosage($1mg/m{\ell}$). 2. SHP showed the effect of decreased the activity of glycerol-3-phosphate dehydrogenase (GPDH) on the high dosage($1mg/m{\ell}$). 3. Investigated the changes in lipolysis of differentiated adipocyte after treated SHP, we knew that these pharmacopuncture showed increasing the effect of lipolysis in all concentration significantly. 4. Investigated the histological changes in porcine fat tissue after treated SHP, we knew that these pharmacopuncture showed significant activity to the lysis of extensive cell membranes on high dosage($10.0mg/m{\ell}$). Conclusions : These results suggest that SHP efficiently induces diminishing proliferation of preadipocyte and lipolysis in adipose tissue.

• ETRI Journal
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• v.34 no.4
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• pp.485-491
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• 2012

In this paper, the implementations of a $0.1{\mu}m$ gallium arsenide (GaAs) pseudomorphic high electron mobility transistor process for a low noise amplifier (LNA), a subharmonically pumped (SHP) mixer, and a single-chip receiver for 70/80 GHz point-to-point communications are presented. To obtain high-gain performance and good flatness for a 15 GHz (71 GHz to 86 GHz) wideband LNA, a five-stage input/output port transmission line matching method is used. To decrease the package loss and cost, 2nd and 4th SHP mixers were designed. From the measured results, the five-stage LNA shows a gain of 23 dB and a noise figure of 4.5 dB. The 2nd and 4th SHP mixers show conversion losses of 12 dB and 17 dB and input P1dB of -1.5 dBm to 1.5 dBm. Finally, a single-chip receiver based on the 4th SHP mixer shows a gain of 6 dB, a noise figure of 6 dB, and an input P1dB of -21 dBm.

• IMMUNE NETWORK
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• v.6 no.2
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• pp.67-75
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• 2006

Background: Cytotoxic function of killer cells is inhibited by specific recognition of class I MHC molecules on target cells by inhibitory killer Ig-like receptors (KIR) expressed on NK cells and some cytotoxic T cells. The inhibitory effect of KIR is accomplished by recruitment of SH2-containing protein tyrosine phosphatase (SHP) to the phosphotyrosine residues in the cytoplasmic tail. Methods: By in vitro coprecipitation experiments and transfection analysis, we investigated the association of KIR with an adaptor protein Shc in Jurkat T cells. Results: The cytoplasmic tail of KIR appeared to associate with an adaptor protein Shc in Jurkat T celilysates. Similar in vitro experiments showed that phosphorylated KIR cytoplasmic tail bound SHP-1 and Shc in Jurkat T cell lysates. The association of KIR with Shc was further confirmed by transfection analysis in 293T cells. Interestingly, however, Shc appeared to be replaced by SHP-2 upon engagement of KIR in 293T cells. Conclusion: Our data indicate that KIR associate with an adaptor protein Shc in Jurkat T cells, and suggest that KIR might have an additional role which is mediated by this adaptor protein.

• Clinical and Experimental Reproductive Medicine
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• v.28 no.2
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• pp.141-145
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• 2001

Objective: We inversigated Small Heterodimer Partner (SHP) gene mutation in Korean Polycystic Ovarian Syndrome (PCOS) patients. SHP protein regulates the activity of nuclear receptors which regulate the cellular development and differentiation. Recently, the mutation of SHP gene was found in the obesity and diabetes patients in Japanese group, and suggested that its mutation may involved in pathogenic mechanism of PCOS. Methods: This study was performed in 20 PCOS patients and 20 normal women. The DNAs were extracted from the peripheral bloods, and amplified at each exon (1 and 2) of SHP gene by PCR method. Subsequently, each PCR product was digested with the restriction enzyme indicated below for studying restriction fragment length polymorphism (RFLP). After enzyme digestion, the results of RFLP were compared PCOS patients with control women to find any sequence variation. Results: We examined 9 regions of exon 1 with Msp I, Pvu II, Dde I and 3 regions of exon 2 with Pst I, Dde I. There is no heterozygous or homozygous mutation in patients and control women at these restriction sites. Conclusion: The genetic analysis at our restriction sites in the SHP gene did not show any genetic variation in Korean PCOS patients. Our PCR-RFLP analysis was not covered the entire SHP gene (68 bp/1,006 bp), we need to further analysis of the entire SHP gene.

• Journal of IKEEE
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• v.3 no.1 s.4
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• pp.69-78
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• 1999

In this paper, direct conversion receiver was designed to even harmonic anti-paralled diode pair ring mixer. Using a second harmonic component of LO instead of LO signal and RF signal are mixed by SHP(Sub Harmonic Pumped) mixer with anti-parallel diode pair. Canceling the harmonics of LO signal in ring mixer, SHP mixer using anti-parallel diode pair could mostly reduce the radiation of LO signal through a input port the most, good isolation characteristic, and low spurious characteristic by LO signal was shown over broad band. The produced SHP mixer showed LO/IF, RF/IF and LO/RF isolation was 24.6dB,36.2dB and 22.5dB respectively. And conversion loss was measured 15.6dB, IF output -35.6dBm with -20dBm RF input and 5.5dBm LO signal. 1dB compression point of If signal, in respect to RF signal, was found at the 0dbm RF signal.

• Journal of Navigation and Port Research
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• v.28 no.10 s.96
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• pp.875-879
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• 2004

In this paper, sub-harmonic pumped(SHP) mixer using anti-parallel diode pair(APDP) is designed for 5 GHz band wireless communication system. Conventional mixers mix LO with RF, and obtain IF signal from the difference between LO and RF. As the frequency increase, LO signal requires higher LO power, better phase noise characteristics, more stable La. However, using APDP, the SHP mixer mixes the 2nd harmonics of LO signal. Therefore, the SHP mixer has an advantage that the LO signal frequency required for IF signal is reduced at half value of LO fundamental frequency. When LO power is 3 dBm, the conversion loss of manufactured SHP mixer is 12.83 dB. The isolation of LO/IF, 2LO/IF, RF/1F and LO/RF is 39.17 dB, 58 dB, 34 dB, and 67.9 dB. respectively. For this case, IP3 at input is 8 dBm.

• Water Engineering Research
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• v.2 no.1
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• pp.11-19
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• 2001

A performance prediction model for Small Hydro Power(SHP) sites has been studied and developed. Twelve SHP sites were selected and the performance characteristics were analyzed by using the developed model. Also, primary design specifications such as design flowrate, plant capacity, operational rate were suggested and feasibility for small hydro power sites were estimated. It was found that the design flowrate is most important parameter to exploit SHP plant and the methodology developed in this study can be a useful tool to analyze the performance of SHP sites.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.6
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• pp.2533-2539
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• 2014

Aim: To take a deeper insight into the relationship between the root of the inferior mesenteric artery (IMA) and the autonomic nerve plexuses around it by cadaveric anatomy and explore anatomical evidence of autonomic nerve preservation in high ligation of the IMA in laparoscopic surgery for colorectal cancer. Methods: Anatomical dissection was performed on 11 formalin-fixed cadavers and 12 fresh cadavers. Anatomical evidence-based autonomic nerve preservation in high ligation of the IMA was performed in 22 laparoscopic curative resections of colorectal cancer. Results: As the upward continuation of the presacral nerves, the bilateral trunks of SHP had close but different relationships with the root of the IMA. The right trunk of SHP ran relatively far away from the root of IMA. When the apical lymph nodes were dissected close to the root of the IMA along the fascia space in front of the anterior renal fascia, the right trunk of SHP could be kept in suit under the anterior renal fascia. The left descending branches to SHP constituted a natural and constant anatomical landmark of the relationship between the root of IMA and the left autonomic nerves. Proximal to this, the left autonomic nerves surrounded the root of the IMA. Distally, the left trunk of the SHP departed from the root of IMA under the anterior renal fascia. When high ligation of the IMA was performed distal to it, the left trunk of SHP could be preserved. The distance between the left descending branches to SHP and the origin of IMA varied widely from 1.3 cm to 2.3 cm. Conclusions: The divergences of the bilateral autonomic nerve preservation around the root of the IMA may contribute to provide anatomical evidence for more precise evaluation of the optimal position of high ligation of the IMA in the future.