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Biomedical subjects

Hui Chen

Publications and source records attributed to Hui Chen.

At least 73 records · Page 4Linked to original sources

[Clinical application of the distally based sural island flap and myofasciocutaneous flap].

OBJECTIVE: To investigate the clinical efficiency of the distally based sural island flap and myofasciocutaneous flap in reconstruction of defect and osteomyelitic cavity of the ankle and foot. METHODS: From June 1997 to October 2004, 21 patients with soft tissue defects and osteomyelitis in the ankle and foot were treated with the distally based sural island flap and myofasciocutaneous flap. There were 20 males and 1 female aging from 6 to 78 years. The defect was caused by soft tissue defect trauma (18 cases) and electrical injury (3 cases). Among 21 patients, 17 were treated with island flaps, 4 by the myofasciocutaneous flap. The size of flaps ranged from 4 cm x 5 cm to 16 cm x 22 cm. The donor sites were closed directly in 4 cases. RESULTS: The flaps completely survived in 21 cases and healing by first intention was achieved. After a follow-up of 3-6 months, no complication occurred. The color and texture of the flaps were good. The appearance and the function were satisfactory. CONCLUSION: Distally based sural flap is a reliable flap. This flap has rich blood supply without sacrifice of major arteries. Flap elevation is easy. It is very useful in repairing large soft tissue defects of the lower leg, the ankle and the foot, especially in repairing deep soft tissue defects and osteomyelitic cavities.

Adolescent↗

[Effects of hydrocortisone on circulating and intramyocardial inflammatory mediators in severe septic rats with myocardial injury induced by Escherichia coli].

OBJECTIVE: Severe sepsis and septic shock remain the most common cause of death in intensive care units. The main causes of death in sepsis are the cardiac dysfunction and hypotension resistant to cateolamines. The prevalence of relative adrenal insufficiency in severe sepsis and septic shock was estimated at about 32%-51%. Several meta-analysis demonstrated that high-dose glucocorticoids decreased survival during sepsis, while stress doses of corticosteroids may benefit these patients. The exact reason for such widely divergent outcome produced by different doses of corticosteroid is still not understood. Therefore, the study was undertaken to observe the effects of different doses of hydrocortisone (HC) on circulating and intramyocardial inflammatory mediators in severe septic rats with myocardial injury induced by Escherichia coli (E. coli). METHODS: The model was established by two injections of inactivated E. coli Forty male Wistar rats were randomly divided into five groups: high-dose of HC group (150 mg/kg), medium-dose group (20 mg/kg), low-dose group (6 mg/kg), model group (NS substituted for HC), and control group (NS for E. coli and HC). Each group had eight rats. After 2 hours of treatment, specimens were collected to measure serum cardiac troponin I (cTnI), tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta), nitric oxide (NO) and total NO synthase (NOS). NO and total NOS in myocardial homogenate were also detected. The expression of inducible NOS (iNOS) of myocytes was investigated. RESULTS: All the above-mentioned markers in model group significantly higher than those in control group. After HC injection, serum cTnI concentrations in low-dose group decreased to normal values compared to that of model group, while in another two HC groups, the concentrations were higher than those in model group. TNF-alpha level was not significantly influenced. But IL-1beta level declined to normal values, being prominent in low-dose HC group. Neither high-dose nor middle-dose HC could lower serum NO or total NOS, but low-dose HC could greatly inhibit both NO and NOS levels (P < 0.05). There was no significant difference in the level of NO and total NOS of myocardial homogenate between left and right ventricles. There was no iNOS expression by normal myocardium, while the expression in model group was significantly increased. After HC injection, the iNOS expressions by myocardium in three HC groups were weaker than those in model group. The intensity of iNOS signals became weak with the decrease in HC dose. CONCLUSION: Different doses of HC might exert different effects on circulating and intramyocardial inflammatory mediators in severely septic rats with myocardial injury induced by E. coli. Low-dose HC could significantly inhibit such mediators as well as iNOS expression by cardiomyocytes. The results suggest that low dose HC exert protective effect on myocardial injury of severely septic rats.

Animals↗

[Valsartan eluting-stents inhibited neointimal hyperplasia by decreasing collagen deposition in rabbits].

OBJECTIVE: To assess the effect of valsartan eluting-stents on restenosis and collagen deposition in neointima hyperplasia in rabbits. METHODS: Valsartan eluting-stents and the carrier eluting-stents were made with patented multi-layers coating techniques. Bare stents (n = 8), carrier eluting-stents (n = 8) and valsartan eluting-stents (n = 10) were implanted into rabbit abdominal aortas, respectively. Quantitive angiography (QA) was performed before, immediately post and 3 months after stents implantations to determine the diameter of aortas. Rabbits were killed 3 months post stents implantation and the cross sections of the stented vessels were analyzed for neointimal formation: luminal area (LA), neointimal area (NIA), inner elastic lumina area (IELA), the maximal inner-membrane thickness (MIT) and percent stenosis. MASSON and picrosirius red staining were performed to observe the collagen deposition in neointima analyzed. RESULTS: The mean aortic diameters measured by QA at different time points were similar between the groups. LA was significantly larger (5 016 269 microm(2) +/- 207,934 microm(2) vs. 4,345,548 microm(2) +/- 125,822 microm(2) and 4,302,061 microm(2) +/- 167,952 microm(2), P < 0.01 vs. valsartan stents) while NIA (441,577 microm(2) +/- 74,099 microm(2) vs. 1,119,635 microm(2) +/- 163,503 microm(2) and 1,135,636 microm(2) +/- 136,555 microm(2)) and MIT (116 microm +/- 12 microm vs. 240 microm +/- 30 microm and 192 microm +/- 21 microm) as well as percent stenosis (8% +/- 2% vs. 20% +/- 2% and 21% +/- 2%) were significantly reduced in valsartan eluting-stents group compared to bare and carrier stents groups. MASSON and picrosirius red staining revealed rich type III collagen deposition in neointima and spare type I collagen patched around stents struts in bare and carrier stents groups and collagen deposition was rarely seen in neointima and stents struts in valsartan eluting-stents group. CONCLUSION: Valsartan eluting-stents inhibited neointimal hyperplasia by decreasing collagen deposition.

Animals↗

[Regulation of anticoagulation effect of human umbilical vein endothelial cells by thrombomodulin gene transfection].

OBJECTIVE: To transfect pcDNA3.1/hTM plasmids containing human thrombomodulin (hTM) gene into human umbilical vein endothelial cells (HUVECs), and investigate the expression of hTM and anticoagulating function of transfected HUVECs. METHODS: HUVECs were transfected with pcDNA3.1/hTM by lipofectin. Expression of hTM mRNA was determined by semi-quantitative RT-PCR, hTM antigen on HUVECs membrane by immunohistochemistry, and activated protein C (PC) in HUVECs by chronometry. By using a semiautomatic coagulator, the effect of the reacting liquid from transfected HUVECs mixed with PC from normal peripheral blood was assayed. RESULTS: About 10% HUVECs were transfected by pcDNA3.1/hTM with high-level hTM mRNA and protein expression. Activated PC produced by pcDNA3.1/hTM group, pcDNA3.1(+)/neo group and untransfected group was (2.80 +/- 0.43) microg/ml, (0.75 +/- 0.08) microg/ml and (0.85 +/- 0.11) microg/ml, respectively. APTT was (51.68 +/- 2.73) s, (38.38 +/- 2.44) s, (39.65 +/- 2.39) s, (33.93 +/- 1.73) s and (34.60 +/- 1.86) s and PT was (21.89 +/- 1.66) s, (20.56 +/- 1.74) s, (20.42 +/- 2.04) s, (19.57 +/- 1.36) s and (20.16 +/- 1.35) s in pcDNA3.1/hTM group, pcDNA3.1(+)/neo group, untransfected group, inactivating PC group and control, respectively. CONCLUSIONS: The pcDNA3.1/hTM plasmid could be transfected into endothelial cells and expressed biologically functioning hTM protein on HUVECs membrane. Activated PC could inhibit intrinsic coagulation pathway obviously with slight effect on extrinsic pathway.

Cells, Cultured↗

[Analysis of phthalates in plastic food-packaging bags by thin layer chromatography].

The method for simultaneous determination of four phthalates, namely dimethyl phthalate (DMP), diethyl phthalate (DEP), di-n-butyl phthalate (DBP) and di (2-ethylhexyl) phthalate (DEHP) in plastic food-packaging bags by thin layer chromatography (TLC) was developed. The plastic food-packaging bags were extracted with ethanol by ultrasonication, then the mixture was filtrated through membrane (0.45 microm). The mixture of ethyl acetate-anhydrous ether-isooctane (1 : 4 : 15, v/v) was used as developing agent on the TLC silica gel plate for development. The filtered liquid was spotted on the TLC plate dealt by acetone, and detected with scanning wavelength of 275 nm and reference wavelength of 340 nm. The qualitative analysis of the phthalates was performed using the R(f) values of the chromatogram. The quantitative analysis was performed with external standard method. Good linearities were obtained for DMP, DEP, DBP and DEHP. The detection limits were 2.1 ng for DMP, 2.4 ng for DEP, 3.4 ng for DBP and 4.0 ng for DEHP. The relative standard deviations (RSDs) of the four phthalates were 2.8% - 3.5%. The recoveries of the four phthalate standards in real sample were 78.58% - 111.04%. The method presented has the advantages of high precision, high sensitivity, small sample size, and simple pretreatment . The method was used to detect the four phthalates in the food-packaging bags. The contents in real samples were close to the results by gas chromatography.

Benzoates↗

[Prospective study on family burden following traumatic brain injury in children].

OBJECTIVE: To collect basic information on family burdens and long-term influence of children suffered from traumatic brain injury (TBI). METHODS: Through prospective study, child behavioral problems, and injury-related family burden were assessed longitudinally in children with TBI over 6 months during the post injury period and children's pre-injury family function rated by parents soon after injury. Post injury child behavior and family outcomes were assessed at 6-month follow-up period. RESULTS: The mean adaptation partnership growth affection and resolve scale (APGAR) score of 113 children before TBI was 7.96 and score after TBI was 6.94, which had significantly difference through t test. The mean APGAR score after 6 months was 7.60, which was significantly different from the hospital data. Among group with severe TBI, the family APGAR score in hospital was significantly smaller than that before injury occurred, and the family APGAR score in 6 months after being discharged from the hospital had no significant difference with the score when staying in the hospital. The three leading dimensions among family burden scale of diseases (FBS) scores after TBI were dimension of family economic burden, family daily life and family entertainment. 6 months later, the three leading dimensions had changed to be as dimension of mental health status, dimension of family relationship and dimension of family economic burden. Mean score of child behavior checklist (CBCL) assessed at 6-months follow up period among 113 children was among normal range. CONCLUSIONS: Family function of children with TBI was affected by TBI. However, family function could be recovered along with child's convalescence except among children with severe TBI. Long-term pressure of TBI on family was revealed in mental health status and family relationship. In this study, there were no evidence of association between TBI and children's behavior problem.

Brain Injuries↗

Identification and genetic mapping of a novel gene involved in pollen development in arabidopsis.

With an aim of the genetic dissection of anther and pollen development, we identified an Arabidopsis mutant line named zy1511 by ethyl-methane sulphonate (EMS) mutagenesis. Genetic analysis indicated that the mutant phenotype was controlled by a single recessive nuclear gene zy1511. Cytological studies of anther at various developmental stages indicated that the mutant anther tapetum did not start degenerating after microspores released from the tetrads. Part of the mutant anther tapetum still existed at late stages of anther development, indicating that mutant tapetum degenerated later than that of the wild-type. So the mutant microspores could not develop into normal pollen grains in the anther. For the further genetic analysis and the map-based cloning of gene zy1511, we have mapped it to a region of 134 kb between molecular markers F25P12 and T8L23 on chromosome 1 using a map-based cloning strategy. As no male sterile genes have been reported in this region, we believe that zy1511 is an undiscovered key gene involved in pollen development.

Arabidopsis↗

[Clinical analysis on high-sensitivity C-reactive protein in hypertensive patients with blood-stasis syndrome].

OBJECTIVE: To study the correlation of serum high-sensitivity protein (hs-CRP) level and the clinical score of blood-stasis syndrome as well as the clinical indexes in hypertensive patients. METHODS: Levels of serum hs-CRP, blood lipids, fasting blood glucose (FBG), body mass index (BMI), left ventricular mass index (LVMI), fibrinogen (Fg), urinary albumin (UA), and score of blood-stasis syndrome (SBSS) in 117 patients were measured, and the relationship between hs-CRP and the other indexes was analyzed. RESULTS: Spearman rank correlation analysis showed that hs-CRP level was significantly positively correlated with SBSS, triglyceride (TG), FPG, BMI, LVMI, Fg, and UA, while negatively correlated with high density lipoprotein cholesterol (HDL-C). CONCLUSION: Hs-CRP is closely related with the formation and development of blood-stasis syndrome in hypertensive patients.

Adult↗

[Continuous blood purification in the treatment of pediatric septic shock].

OBJECTIVE: To investigate the efficacy of continuous blood purification (CBP) and to explore its mechanism in the treatment of pediatric septic shock. METHODS: Nine children weighted 3.1 kg - 14.0 kg with septic shock were treated with continuous veno-venous hemofiltration (CVVH) which is also referred to as CBP with blood access of double-lumen hemodialysis catheter of 6.5 to 8Fr inserted via central vein, hemofilters of Minifilter plus (for children with body weight < 5 kg) or AV400s (for children with body weight > or = 5 kg), child's type extracorporeal circuit vessel and heparin anticoagulation. The replacement solution was delivered pre-dilution after 3 to 4 hours' post-dilution. The blood gas, clinical biochemical items, medium molecule substance (MMS) concentration in blood as well as capillary refill time (CRT), BP, urine output, vasopressors dosage were examined at a set of time points from the beginning to the end of the CVVH. RESULTS: Of the 9 children, 6 had acute renal failure (ARF), 3 had acute respiratory distress syndrome (ARDS), 5 were blood culture positive and all the 9 needed vasopressors to keep BP before CVVH. The blood pH was 7.14 +/- 0.23, base excess (BE) was -11.3 +/- 4.25 mmol/L, MMS was 3532 +/- 519 U/L, PO2/FiO2 was 188 +/- 33, CRT > 5 s, urine output was 0.85 +/- 0.52 ml/(kg.hr) and the adrenalin dosage 1.36 +/- 0.48 microg/(kg.min), and dopamine 16.35 +/- 3.27 microg/(kg.min) before CVVH. The patients' condition was improved much as demonstrated by pH 7.38 +/- 0.16, BE -0.28 +/- 1.37 mmol/L, MMS 2576 +/- 375 U/L, PO2/FiO2 285 +/- 63, CRT < 2 s, and the adrenalin dosage 0.08 +/- 0.04 microg/(kg.min) and dopamine 8.53 +/- 6.72 microg/(kg.min), urine output 2.9 +/- 1.6 ml/(kg.hr) after 24 hour treatment with CVVH. Of the 9 children, 2 died of MODS (1 intussusception complicated with intestine necrosis, 1 severe scald) and 1 was given up because of severe intestinal fistula, the other 6 children recovered at the end. CONCLUSION: CBP was effective in treatment of pediatric septic shock by improving the oxygenation, correcting metabolic acidosis, stabilizing BP, increasing the tissue perfusion and eliminating the medium molecule substances.

Acid-Base Equilibrium↗

[Selective determination for calf thymus DNA by a resonance light scattering technique with morin-Ce(IV) system].

The interaction of DNA and the binary complex formed between Ce(IV) and morin was studied. With the maximum scattering peak located at 320 nm, the enhanced RLS was proportional to the concentration of ctDNA in the range 0-25 microg x mL(-1) and the detection limit (3sigma) of 0.3 microg x mL(-1) was obtained. Under the optimized conditions, four synthetic samples were determined with recoveries in the range 93.7%-108.4%. The proposed method is particularly attractive for its high selectivity for ctDNA in the presence of hsDNA by using certain sensitive spectrofluorometer since the intensity of RLS for hsDNA is far weaker than that for ctDNA.

Animals↗

[Associations between periodontal status and delivery outcomes in pregnant women with a diagnosis of threatened premature labor].

OBJECTIVE: To evaluate the association between periodontal conditions and delivery outcomes in pregnant women with a diagnosis of threatened premature labor (TPL). METHODS: Eighty systemically healthy pregnant women were enrolled in the study. Forty of these were pregnant women hospitalized with the diagnosis of TPL, and 40 normal pregnant women served. TPL was control clarified as TPL-PB (14 women) and TPL-TB (26 women) based on the delivery outcomes. No infants were delivered as PB in the control with non-TPL. Periodontal examinations included assessments of plaque index (PLI), clinical attachment loss (CAL), probing depth (PD), bleeding index (BI) and the percentage of periodontitis sites (PD > 3 mm, CAL >or= 2 mm). The serum level of TNF-alpha was determined using commercially available enzyme-linked immunoassays (ELISA). RESULTS: The mean PLI (0.94 +/- 0.05), percentage of periodontitis sites (2.93%) and TNF-alpha levels [14.81 ng/L (13.40 - 15.64 ng/L)] were significantly higher in the TPL group than in the non-TPL group [0.59 +/- 0.03, 1.32% and 11.47 ng/L (10.82 - 12.86) ng/L] (P < 0.001). The mean PLI (0.96 +/- 0.06), BI (2.99 +/- 0.14), percentage of periodontitis sites (3.61%) and TNF-alpha levels [18.35 ng/L (15.47 - 31.94) ng/L] were significantly higher in the TPL-PB group than in the TPL-TB group [0.66 +/- 0.04, 2.76 +/- 0.12, 2.25% and 13.70 ng/L (12.64 - 14.80 ng/L)]. Significant negative correlations were observed between the gestational age at delivery and percentage of periodontitis sites as well as serum TNF-alpha levels (P < 0.05). And significant positive correlations were observed between percentage of periodontitis site and serum TNF-alpha levels (P < 0.05). CONCLUSIONS: Periodontal inflammation might be involved in the pathogenesis of preterm birth.

Adult↗

[Construction of urban green space ecosystem by using corridor network: a case study in west urban area of Dongying City, Shandong Province].

This paper discussed the ecological significance of urban green corridors network in urban green space ecosystem, analyzed the present status of green space ecosystem in the west urban area of Dongying in Shangdong Province, and figured out the ways of constructing urban green corridors network in this area to strengthen the linkage between its fragmented greenbelts, and between these greenbelts and rural natural environment. Through the construction of this network, the greenbelt area in the west urban area of Dongying would increase 1400 hm2, greenbelt area per capita would increase to 66 m2, and urban and rural greenbelts would be integrated into a whole system to serve the whole city, giving a powerful support to enhance the life quality of local people and the stability of urban ecosystem.

China↗

[Raman active vibrations of aluminosilicates].

Raman spectra of aluminosilicate minerals, namely kyanite, andalusite, and sillimanite and K2O-Al2O3-SiO2 glasses were recorded. Four alumino-silicon tetrahedral model clusters were calculated by self-consistent (SCF) molecular orbital ab-ini-tio calculation of the quantum chem (QC) method. The result shows a decrease tendency in Raman frequencies in the 800-1200 cm(-1) frequency region with increase in four-coordinated Al content, which is assigned to the Si--Onb symmetry stretching vibrations. The Raman spectra in the 700-800 cm(-1) frequency region is attributed to Al-Onb symmetry stretching vibrations.

English Abstract↗

Dehydroepiandrosterone mimics acute actions of insulin to stimulate production of both nitric oxide and endothelin 1 via distinct phosphatidylinositol 3-kinase- and mitogen-activated protein kinase-dependent pathways in vascular endothelium.

Dehydroepiandrosterone (DHEA) is an adrenal steroid and nutritional supplement that may improve insulin sensitivity. Although steroid hormones classically act by regulating transcription, they may also signal through cell surface receptors to mediate nongenomic actions. Because DHEA may augment insulin sensitivity, we hypothesized that DHEA mimics vascular actions of insulin to acutely activate signaling pathways in endothelium-mediating production of nitric oxide (NO) and endothelin 1 (ET-1). Treatment of bovine aortic endothelial cells with either insulin or DHEA (100 nm, 5 min) stimulated significant increases in NO production (assessed with NO-selective fluorescent dye diaminofluorescein 2). These responses were abolished by pretreatment of cells with L-NAME (nitro-L-arginine methyl ester; NO synthase inhibitor) or wortmannin [phosphatidylinositol (PI) 3-kinase inhibitor]. Under similar conditions, insulin- or DHEA-stimulated phosphorylation of Akt (Ser473) and endothelial nitric oxide synthase (Ser1179) was inhibited by pretreatment of cells with wortmannin (but not MAPK kinase inhibitor PD98059). Acute DHEA treatment also caused phosphorylation of MAPK (Thr202/Tyr204) that was inhibitable by PD98059 (but not wortmannin). DHEA treatment of bovine aortic endothelial cells (100 nM, 5 min) stimulated a 2-fold increase in ET-1 secretion that was abolished by pretreatment of cells with PD98059 (but not wortmannin). We conclude that DHEA has acute, nongenomic actions in endothelium to stimulate production of the vasodilator NO via PI 3-kinase-dependent pathways and secretion of the vasoconstrictor ET-1 via MAPK-dependent pathways. Altering the balance between PI 3-kinase- and MAPK-dependent signaling in vascular endothelium may determine whether DHEA has beneficial or harmful effects relevant to the pathophysiology of diabetes.

Animals↗

Jasmonate-inducible plant enzymes degrade essential amino acids in the herbivore midgut.

The plant hormone jasmonic acid (JA) activates host defense responses against a broad spectrum of herbivores. Although it is well established that JA controls the expression of a large set of target genes in response to tissue damage, very few gene products have been shown to play a direct role in reducing herbivore performance. To test the hypothesis that JA-inducible proteins (JIPs) thwart attack by disrupting digestive processes in the insect gut, we used a MS-based approach to identify host proteins that accumulate in the midgut of Manduca sexta larvae reared on tomato (Solanum lycopersicum) plants. We show that two JIPs, arginase and threonine deaminase (TD), act in the M. sexta midgut to catabolize the essential amino acids Arg and Thr, respectively. Transgenic plants that overexpress arginase were more resistant to M. sexta larvae, and this effect was correlated with reduced levels of midgut Arg. We present evidence indicating that the ability of TD to degrade Thr in the midgut is enhanced by herbivore-induced proteolytic removal of the enzyme's C-terminal regulatory domain, which confers negative feedback regulation by isoleucine in planta. Our results demonstrate that the JA signaling pathway strongly influences the midgut protein content of phytophagous insects and support the hypothesis that catabolism of amino acids in the insect digestive tract by host enzymes plays a role in plant protection against herbivores.

Amino Acid Sequence↗

Prevalence of MDS subtypes in Shanghai, China: a comparison of the World Health Organization and French American British classifications.

The prevalence of subtypes of the myelodysplastic syndromes (MDS) was determined in a prospective series of 176 patients presenting at 28 Shanghai hospitals. Diagnosis was established in a single laboratory, analyzing morphologic, immunophenotypic, and cytogenetic data, using the World Health Organization (WHO) revised classification and directly compared to the French American British (FAB) criteria. The median age at diagnosis for all cases was 53 years. There was a striking increase in the prevalence of RCMD in younger patients relative to other subtypes (WHO). The overall frequency of clonal cytogenetic abnormalities was 26.5% (WHO) and 31% (FAB). The most frequently encountered lesions were trisomy 8, del(20)q, del(7q), and del(5q). These results are consistent with previously reported age-dependent differences in MDS and a decreased frequency of del(5q) abnormalities between China and the West. These results also indicate that multilineage dysplasia is a prominent feature in MDS developing in younger individuals in Shanghai and suggest distinguishing between RCMD and RA may be important in the design of studies to further understand regional differences in subtype prevalence and to elucidate the pathogenesis of this complex and multifactorial disease.

Adolescent↗

Vdelta1 T cell receptor binds specifically to MHC I chain related A: molecular and biochemical evidences.

Human MHC class I chain-related A (MICA) is a tumor-associated antigen that can be recognized by Vdelta1 subset of tumor-infiltrating gammadelta T cells. We previously reported that immobilized recombinant MICA protein could induce the proliferation of tumor-infiltrating Vdelta1 gammadelta T cells in vitro. But there has been no direct evidence showing the engagement of gammadelta T cell receptors (TCR) of the induced cells with MICA. In the current investigation, we show that MICA induces specific cytolytic activity of the expanded gammadelta T cells. We expressed the coupled V domains from the MICA-induced T cells as a single polypeptide chain Vdelta Vgamma TCR (gammadelta scTCR). Such scTCR can specifically bind MICA of HeLa cells. Direct interaction of gammadelta scTCRs with in vitro expressed MICA was monitored using an IAsys biosensor. We found that the Vdelta1 scTCR can specifically bind to immobilized MICA molecule and MICA alpha1alpha2 domains are responsible for the binding reaction.

Antibodies, Monoclonal↗

Studies of the resolution of racemic 1,1'-bi-2-naphthol with a dipeptide chiral selector identified from a small library.

Several new stationary phases were prepared to study the structure-activity relationship of the chiral resolution of racemic 1,1'-bi-2-naphthol with a modified dipeptide Asn-Asn selector. The number of amino acid, the side chain protecting groups of the amino acid, and the Fmoc end-capping group all proved important for enantioselectivity. The linker also influenced enantioselectivity. Influence of the length of the linker appears to be related to the accessibility of chiral selectors. The bond through which the selector is attached to the linker proved important. Based on these results, it is postulated that hydrogen bonding interactions between one side chain amide group of one Asn and the oxygen on the backbone of another Asn with the two hydroxyl groups of the analyte play an important role in the resolution of racemic 1,1'-bi-2-naphthol with the modified dipeptide Asn-Asn selector.

Dipeptides↗