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Surface-enhanced Raman scattering (SERS) induced from nanostructured noble metals has a great potential for molecular detection and analysis. However, it has been a challenge to fabricate a reliable SERS-active nanostructure that produces highly sensitive signal response with high fidelity for use in the practical sensing platform. Here, a bacteriophage MS2 with highly regular structure was introduced as a molecular scaffold to assemble nanoparticles into a dense and reproducible three-dimensional raspberry-shaped nanostructure. The nanoraspberry features evenly distributed electromagnetic hot spots responsible for single-molecule-level analysis of SERS-based sensing. By selecting a rigid molecular linker, as well as MS2 phage, the gold nanoparticles were able to be assembled into nanoraspberry superstructures with precisely defined positions, producing strong electric near-field enhancement between nanometer-sized interparticle gaps. The numerical simulation and experimental measurement demonstrated that the nanoraspberry structure produces strong SERS signal amplification, with remarkable intra- and interbatch signal uniformity, proving that structural reproducibility originated from rigid building blocks can lead to a reliable SERS measurement for molecular sensing and analysis applications.

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Background. Toluene diisocyanate (TDI) causes occupational asthma by generating oxidative stress, leading to tissue injury and inflammation. Glutathione transferases (GSTs) are detoxifying enzymes that eliminate oxidative stress. We examined whether the genotypes of the GSTM1 and GSTT1 genes are associated with TDI-induced occupational asthma (TDI-OA). Methods. The study population consisted of 26 asthmatics with a positive response to the TDI challenge (TDI-PA) and 27 asthmatics with negative responses (TDI-NA). GSTM1 and GSTT1 null and wild-type genotypes were determined using multiplex PCR. The plasma GSTM1 and GSTT1 protein concentrations were determined using ELISA. Results. The GSTM1 null genotype was more frequent in the TDI-PA than in the TDI-NA (77.8 vs. 50.0%, OR = 3.5, p=0.03), while the frequency of the GSTT1 null genotype tended to be higher in the TDI-PA than in the TDI-NA (59.3 vs. 42.3%, OR = 1.98, p=0.21). When analyzed together, the GSTM1/GSTT1 null genotype was more frequent in the TDI-PA than in the TDI-NA (48.2 vs. 15.3%, OR = 6.5, p=0.04). The decline in the FEV in 1 s after TDI challenge was higher with the GSTM1/GSTT1 null than the GSTM1 wild-type/GSTT1 null genotypes (24.29% vs. 7.47%, p=0.02). The plasma GSTM1 level was lower with the GSTM1 null than with the GSTM1 wild-type genotypes both before (13.7 vs. 16.6 ng/mg, p=0.04) and after (12.9 vs. 17.1 ng/mg, p=0.007) the TDI challenge, while the GSTT1 level was not changed with either the GSTT1 null or wild-type genotype. Conclusions. The GSTM1 null genotype, but not GSTT1 alone, may confer susceptibility to TDI-OA. However, the genetic effect of the GSTM1 null genotype may be enhanced synergistically by the GSTT1 null genotype. The genetic effect of GSTM1 was validated in the plasma as the GSTM1 protein level. Therefore, the GSTM1 and GSTT1 genotypes may be useful diagnostic markers for TDI-OA.

Background. Quinoline-3-carboxamides have been used to treat autoimmune/inflammatory diseases in humans because they inhibit the functions of S100 calcium-binding protein A9 (S100A9), which participates in the development of neutrophilic inflammation in asthmatics and in an animal model of neutrophilic asthma. However, the therapeutic effects of these chemicals have not been evaluated in asthma. The purpose of this study was to evaluate the effect of paquinimod, one of the quinoline-3-carboxamides, on a murine model of neutrophilic asthma. Methods. Paquinimod was orally administered to 6-week-old C57BL/6 mice sensitized and challenged with ovalbumin (OVA)/complete Freund’s adjuvant (CFA) and OVA. Lung inflammation and remodeling were evaluated using bronchoalveolar lavage (BAL) and histologic findings including goblet cell count. S100A9, caspase-1, IL-1β, MPO, IL-17, IFN-γ, and TNF-α were measured in lung lysates using western blotting. Results. Paquinimod restored the enhancement of airway resistance and the increases in numbers of neutrophils and macrophages of BAL fluids and those of goblet cells in OVA/CFA mice toward the levels of sham-treated mice in a dose-dependent manner (0.1, 1, 10, and 25 mg/kg/day, p.o.). Concomitantly, p20 activated caspase-1, IL-1β, IL-17, TNF-α, and IFN-γ levels were markedly attenuated. Conclusion. These data indicate that paquinimod effectively inhibits neutrophilic inflammation and remodeling in the murine model of neutrophilic asthma, possibly via downregulation of IL-17, IFN-γ, and IL-1β.

The best prognostic predictor for acute leukemia is known to be the finding of genetic abnormalities of leukemic cells. Methods for detecting the genetic abnormalities include chromosomal studies for karyotyping, FISH(Fluorescence in situ hybridization) and RT-PCR. However, each methods have limitations i.e. low sensitivity in karyotyping, uncertainty of molecular probe to be used in FISH or RT PCR methods. Multiplex RT-PCR (MRT-PCR) allows simultaneous detection of 28 fusion genes, more than 80 breakpoints and splice variants associated with leukemia. Therefore, this method can be used for detection of molecular abnormality in fresh unknown leukemic cases, as well as for molecular remission in follow-up cases. The aim was to demonstrate whether MRT-PCR system might be successfully used to screen a large number of patients with acute leukemia and compare the result with that of chromosome studies. Frozen bone marrow cells from 78 patients, who were diagnosed with acute leukemia at Ajou university hospital between September 1994 and February 2004, were used for MRT-PCR. In all samples with a known conventional cytogenetic results, we performed MRT-PCR and to compared with conventional cytogenetic study regarding the concordance rate and analyzed discordant cases regarding their types. 78 samples(40 male and 38 female patients) were analyzed, and there were 59 AML patients and 19 ALL patients. We successfully obtained the mRNA from all frozen samples. In 21 cases with gene abnormalities by chromosome studies most of them (15/21) showed the same abnormalities with MRT-PCR. In 57 patients with normal karyotype by cytogenetic technique, we identified 18 translocations of clinical significance by MRT-PCR method. In 18 discordant cases, there were 4 cases with t(15;17), 4 cases with t(8;21), 3 cases with t(9;22), 2 cases with t(11;19) and 4 others [t(9;11),t(9;9),t(3;11),inv(16)]. Conventional cytogenetics detected 10 cases of good prognostic gene abnormalities [t(15;17),t(8;21),inv(16)], but MRT-PCR method detected 10 additional cases of good prognostic gene abnormalities which might change the treatment paln. The twenty good prognostic cases with MRT-PCR showed better overall survival than others. (median f/u = 10.6 month, p=0.0443) There were 69% concordance rate between cytogenetic technique and MRT-PCR. Furthermore clinically significant translocations were detected by MRT-PCR in 18 of 57 normal karyotype patients, indicating improved sensitivity and prognostic value with MRT-PCR. Further investigations are needed to ascertain the usefulness of MRT-PCR for the screening tool of leukemic gene abnormalities.

The best prognostic predictor for acute leukemia is known to be the finding of genetic abnormalities of leukemic cells. Methods for detecting the genetic abnormalities include chromosomal studies for karyotyping, FISH(Fluorescence in situ hybridization) and RT-PCR. However, each methods have limitations i.e. low sensitivity in karyotyping, uncertainty of molecular probe to be used in FISH or RT PCR methods. Multiplex RT-PCR (MRT-PCR) allows simultaneous detection of 28 fusion genes, more than 80 breakpoints and splice variants associated with leukemia. Therefore, this method can be used for detection of molecular abnormality in fresh unknown leukemic cases, as well as for molecular remission in follow-up cases. The aim was to demonstrate whether MRT-PCR system might be successfully used to screen a large number of patients with acute leukemia and compare the result with that of chromosome studies. Frozen bone marrow cells from 78 patients, who were diagnosed with acute leukemia at Ajou university hospital between September 1994 and February 2004, were used for MRT-PCR. In all samples with a known conventional cytogenetic results, we performed MRT-PCR and to compared with conventional cytogenetic study regarding the concordance rate and analyzed discordant cases regarding their types. 78 samples(40 male and 38 female patients) were analyzed, and there were 59 AML patients and 19 ALL patients. We successfully obtained the mRNA from all frozen samples. In 21 cases with gene abnormalities by chromosome studies most of them (15/21) showed the same abnormalities with MRT-PCR. In 57 patients with normal karyotype by cytogenetic technique, we identified 18 translocations of clinical significance by MRT-PCR method. In 18 discordant cases, there were 4 cases with t(15;17), 4 cases with t(8;21), 3 cases with t(9;22), 2 cases with t(11;19) and 4 others [t(9;11),t(9;9),t(3;11),inv(16)]. Conventional cytogenetics detected 10 cases of good prognostic gene abnormalities [t(15;17),t(8;21),inv(16)], but MRT-PCR method detected 10 additional cases of good prognostic gene abnormalities which might change the treatment paln. The twenty good prognostic cases with MRT-PCR showed better overall survival than others. (median f/u = 10.6 month, p=0.0443) There were 69% concordance rate between cytogenetic technique and MRT-PCR. Furthermore clinically significant translocations were detected by MRT-PCR in 18 of 57 normal karyotype patients, indicating improved sensitivity and prognostic value with MRT-PCR. Further investigations are needed to ascertain the usefulness of MRT-PCR for the screening tool of leukemic gene abnormalities.