Effect of chemisorbed thiophenols with an electron donating group on surface-enhanced Raman scattering of gold nanorods

Surface-enhanced Raman scattering (SERS) is a powerful technique to amplify the weak Raman scattering intensity by molecules chemisorbed on a metallic surface. Herein, we present the interfacial electronic effect of para-substituted aromatic thiophenols (TPs) with an electron donating group (EDG) on SERS of anisotropic gold nanorods (AuNRs) under resonant conditions. Probe molecules with an EDG showed great SERS enhancement in AuNRs at the resonant excitation wavelength. We found that the SERS enhancement with an EDG is caused by the formation of aggregates through intermolecular interactions among probe molecules, such as dimerization with hydrogen bonding via an amino group (-NH2) of p-aminothiophenol (p-ATP) and hydroxyl group (-OH) of p-mercaptophenol (p-MP), resulting in hot-spots between AuNRs. Furthermore, SERS having a stronger EDG (-NH2, p-ATP) with the Hammett constant of -0.66 exhibited greater enhancement than p-MP having hydroxyl (-OH) groups with the Hammett constant of -0.37. We found that the greater enhancement is ascribed to the temporary formation of a positively charged electron withdrawing group (-NH3+) in p-ATP, unlike p-MP, via the interaction of the lone pair of the amino group (-NH2) with ethanol. Therefore, this investigation provides new insightful experimental observations on SERS enhancement of probe molecules with an EDG.

Primary hepatic extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue

Extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma), is one of the specific type of low-grade B-cell lymphoma not infrequently found worldwide. It typically involves mucosal sites such as stomach and conjunctiva; however, primary hepatic MALT lymphoma has been extremely rarely reported. We describe a case of hepatic MALT lymphoma in a 70-year-old male patient who underwent left hepatectomy due to the incidentally detected liver masses at a medical checkup. The resected specimen revealed multinodular masses consisting of small-to-intermediate-sized lymphoid cells with serpentine pattern and focal lymphoepithelial lesions. The tumor cells were diffusely positive for CD20 and Bcl-2 but negative for CD3, CD10, CD5, CD23, CD43, and cyclinD1. The Ki-67 labeling index was 10% and immunoglobulin heavy chain gene rearrangement study confirmed monoclonal proliferation. In this paper, we discuss several unique clinicopathologic characteristics which will be helpful to the differential diagnosis of hepatic MALT lymphoma.

Indirect Interactions between Raman Probes Encapsulated within Cucurbit[7]urils and Gold Nanorods to Enhance Long-term Stability and Signal

Surface-enhanced Raman scattering (SERS) is a powerful technique that enhances Raman signals by adsorbing probe molecules on rough metal surfaces. However, SERS is limited because target molecules must strongly interact with metal to enhance a stable Raman signal. In this study, to improve long-term SERS stability, we use cucurbit[7]urils (CB[7]) as bridge molecules and sample containers to probe Rhodamine 6G (R6G) molecules. We observed interactions between gold nanorods (AuNRs) and CB[7] via aggregate formation, which enhanced the Raman signal and improved long-term R6G probe stability by up to 20 days when encapsulated within CB[7] during SERS analysis.

Some Mineral Intakes of Koreans Estimated Using Food Composition Database and Real-time Food Analysis Data in Total Diet Study Were Comparable (P10-106-19)

Objectives

Total Diet Study (TDS) determines levels of the analytes in foods as they would be consumed (table-ready). This is particularly important for estimating dietary intake of nutrients, level of which may be changed as a result of preparation. Hence, we attempted to compare some nutrient intakes estimated from food composition databases (FCD) in nutrition survey (NS) and from real-time food analysis data in TDS based on The Korea National Health and Nutrition Examination Survey (KNHANES) 2013–2016.

Methods

We established a nationwide representative dietary intake data set of 4 years from KNHANES 2013–2016. Based on the type of dishes (prepared foods) consumed, 224 pairs of ‘food X cooking methods’ were identified covering more than 92.7% of total food intake of Koreans for calcium, iron and zinc analysis using ICP–MS and ICP–AES.

Results

Mean calcium intake was 460.6 mg/person/day in TDS vs 487.3 mg/person/day in NS. In TDS, the food groups contribute mostly to calcium were milk & dairy (29.6%), vegetables (24.4%), and grains & cereals (12.5%) while they were vegetables (25.6%), milk & dairy (25.3%), and fishes & shellfishes (13.8%) in NS. Calcium intake from milk accounted for 20.8% of total intake in TDS vs 14.3% in NS. Similarly, only 10 foods were necessary to cover half of calcium intake in TDS vs more than 15 in NS.

Iron intake was estimated to be 7.80 mg/person/day in TDS vs 16.9 mg/person/day in NS. The major food groups contributing to iron were vegetables (20.3%), grains & cereals (17.9%), and meats & their products (16.7%) in TDS. On the other hand, they were quite different in NS: grains & cereals (25.3%), vegetables (22.6%), and meats & their products (11.5%). While top iron source was eggs accounting for 7.9% in TDS, it was rice (11.6%) in NS.

Although zinc intake of Koreans has never been officially announced from KNHANES due to incomplete database, we attempted to estimate zinc intake in TDS. Mean zinc intake was 10.16 mg/person/day and major food groups contributing to zinc were grains & cereals (37.2%) and meats & their products (26.0%). Top zinc source was rice (25.2%) and 5 foods were enough to cover half of zinc intake.

Conclusions

While mean mineral intakes of Koreans estimated by 2 methods were quite comparable, more frequent revision of FCD is warranted for staple foods and well-known sources of each nutrient.

Funding Sources

This research was supported by a grant from Ministry of Food and Drug Safety in 2018 (Total Diet Study for Food Standard & Specifications in Korea).

Tuning Chemical Interface Damping: Interfacial Electronic Effects of Adsorbate Molecules and Sharp Tips of Single Gold Bipyramids

The optimization of the localized surface plasmon resonance (LSPR)-decaying channels of hot-electrons is essential for efficient optical and photochemical processes. Understanding and having the ability to control chemical interface damping (CID) channel contributions will bring about new possibilities for tuning the efficiency of plasmonic hot-electron energy transfer in artificial devices. In this scanning electron microscopy-correlated dark-field scattering study, the CID was controlled by focusing on the electronic nature of disubstituted benzene rings acting as adsorbates, as well as the effects of sharp tips on gold bipyramids (AuBPs) with similar aspect ratios to those of gold nanorods. The results showed that the sharp tips on single AuBPs, as well as the electronic effects of the adsorbate molecules, increase the interfacial contact between the nanoparticles and adsorbate molecules. Electron withdrawing groups (EWGs) on the adsorbates induce larger homogeneous LSPR line widths compared to those of electron donating groups (EDGs). Depending on the location (ortho, meta, and para) of the EDG, the effect of benzene rings with an EDG, which was considered to be induced by sulfur atoms bound to the nanoparticle surface, is weakened by the back transfer of electrons facilitated by the difference in the availability of the electrons of the EDG. Therefore, this study reports that the CID in the LSPR total decay channels can be tuned by controlling the electron withdrawing and electron donating features of adsorbate molecules with the surface topology of metal.

Synthesis and structure-activity studies of side chain analogues of the anti-tubercular agent, Q203

The anti-tubercular activity of 6-chloro-2-ethyl-N-(4-(4-(4-(trifluoromethoxy)phenyl)piperidin-1-yl)benzyl)imidazo [1,2-a]pyridine-3-carboxamide (Q203) is modified by varying its side chain. In this study, we synthesized Q203 analogues with different side chains and studied their effects on anti-tubercular activity. Many analogues showed good potency against M. tuberculosis replicating in liquid broth culture medium (extracellular activity) regardless of chain length and conformational changes. However, a polar character in the side chain region was unfavorable for anti-tubercular activity. The analogues, 25, 28, 35, and 36, displayed excellent activity against M. tuberculosis replicating inside macrophages (intracellular activity) and promising pharmacokinetic (PK) properties with high drug exposure level and long half-life.

Angioimmunoblastic T-Cell Lymphoma in a Patient with Klinefelter Syndrome

Patient: Male, 61

Final Diagnosis: AITL in Klinefelter syndrome

Symptoms: —

Medication: —

Clinical Procedure: Chemotherapy

Specialty: Hematology

A correlation between tocopherol content and antioxidant activity in seeds and germinating seeds of soybean cultivars

BACKGROUND

Tocopherols are crucial lipid-soluble antioxidants and essential nutrients. There is increasing interest in the biofortification of crops with vitamin E for reducing micronutrient malnutrition. However, relatively little is known about the development of soybean cultivars with high levels of tocopherol through combined breeding.

RESULT

Tocopherol contents of seeds and germinating seeds of 28 Korean soybean cultivars were analyzed and evaluated for health-promoting activities. Total tocopherol concentrations ranged from 203.9 to 503.1 µg g⁻¹ in seeds and from 20.1 to 230.1 µg g⁻¹ in germinating seeds. The traditional landraces of HaNagari (HN, 503.1 µg g⁻¹), Orialtae (OL, 486.6 µg g⁻¹), SuMoktae (SM, 476.5 µg g⁻¹) and SoRitae (SR, 475.5 µg g⁻¹) showed high levels of tocopherol content. The contents of the four isomers of tocopherol in seeds and germinating seeds were correlated with lipid peroxidation. The γ- and δ-tocopherol contents in seeds were related to 1,1-diphenyl-2-picrylhydrazyl free radical scavenging activity (0.434; P < 0.01 and 0.373; P < 0.05).

CONCLUSION

Total tocopherol content was higher in soybean landraces as compared with modern cultivars developed by cross-breeding. These results suggest that soybean breeding is necessary to increase tocopherol levels.

Performance of (18)F-FDG PET/CT as a postoperative surveillance imaging modality for asymptomatic advanced gastric cancer patients

OBJECTIVE

The purpose of this study was to investigate the diagnostic performance of postoperative fluorine-18 fluoro-2-deoxy-D-glucose ((18)F-FDG) positron emission tomography/computed tomography (PET/CT) as a surveillance modality for advanced gastric cancer patients who were asymptomatic and negative by conventional follow-up.

METHODS

We retrospectively collected 46 advanced gastric cancer patients who received approximately 1-year-postoperative (18)F-FDG PET/CT surveillance following curative resection (mean age 60.6 ± 11.5 years). (18)F-FDG PET/CT was interpreted by nuclear medicine physicians who were blind to the clinical information. Final confirmation was determined by clinical follow-up using tumor markers, conventional CT scan, upper gastrointestinal endoscopy and with/without subsequent histopathologic diagnosis.

RESULTS

Four patients developed recurrence (8.7 %; 1 local and 3 distant recurrences). For local recurrence, (18)F-FDG PET/CT found four hypermetabolic lesions and one was local recurrence. For distant recurrence, seven hypermetabolic lesions were found in six patients and true-positive was three lesions. False-positive cases were mainly turned out to be physiologic small bowel uptake. Regardless of the recurrence site, the sensitivity, specificity, positive predictive value and negative predictive value of (18)F-FDG PET/CT were 100 % (4/4, 95 % confidence interval (CI) 39.6-100 %), 88.1 % (37/42, 95 % CI 73.6-95.5 %), 44.4 % (4/9, 95 % CI 15.3-77.3 %) and 100 % (37/37, 95 % CI 88.3-100 %), respectively in the patient-based analysis.

CONCLUSION

Our study showed good specificity of postoperative surveillance (18)F-FDG PET/CT for detecting recurrence. Careful caution should be made for interpreting some false-positive hypermetabolic lesions in postoperative (18)F-FDG PET/CT, especially at the local anastomosis site.

Lead optimization of a novel series of imidazo[1,2-a]pyridine amides leading to a clinical candidate (Q203) as a multi- and extensively-drug-resistant anti-tuberculosis agent

A critical unmet clinical need to combat the global tuberculosis epidemic is the development of potent agents capable of reducing the time of multi-drug-resistant (MDR) and extensively-drug-resistant (XDR) tuberculosis therapy. In this paper, we report on the optimization of imidazo[1,2-a]pyridine amide (IPA) lead compound 1, which led to the design and synthesis of Q203 (50). We found that the amide linker with IPA core is very important for activity against Mycobacterium tuberculosis H37Rv. Linearity and lipophilicity of the amine part in the IPA series play a critical role in improving in vitro and in vivo efficacy and pharmacokinetic profile. The optimized IPAs 49 and 50 showed not only excellent oral bioavailability (80.2% and 90.7%, respectively) with high exposure of the area under curve (AUC) but also displayed significant colony-forming unit (CFU) reduction (1.52 and 3.13 log10 reduction at 10 mg/kg dosing level, respectively) in mouse lung.

Variation block-based genomics method for crop plants

BACKGROUND

In contrast with wild species, cultivated crop genomes consist of reshuffled recombination blocks, which occurred by crossing and selection processes. Accordingly, recombination block-based genomics analysis can be an effective approach for the screening of target loci for agricultural traits.

RESULTS

We propose the variation block method, which is a three-step process for recombination block detection and comparison. The first step is to detect variations by comparing the short-read DNA sequences of the cultivar to the reference genome of the target crop. Next, sequence blocks with variation patterns are examined and defined. The boundaries between the variation-containing sequence blocks are regarded as recombination sites. All the assumed recombination sites in the cultivar set are used to split the genomes, and the resulting sequence regions are termed variation blocks. Finally, the genomes are compared using the variation blocks. The variation block method identified recurring recombination blocks accurately and successfully represented block-level diversities in the publicly available genomes of 31 soybean and 23 rice accessions. The practicality of this approach was demonstrated by the identification of a putative locus determining soybean hilum color.

CONCLUSIONS

We suggest that the variation block method is an efficient genomics method for the recombination block-level comparison of crop genomes. We expect that this method will facilitate the development of crop genomics by bringing genomics technologies to the field of crop breeding.

Detection of internal mammary lymph node metastasis with (18)F-fluorodeoxyglucose positron emission tomography/computed tomography in patients with stage III breast cancer

PURPOSE

The present study assessed the positive predictive value (PPV) of (18)F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) for the detection of internal mammary node (IMN) metastasis in patients with clinical stage III breast cancer.

METHODS

Patients who were diagnosed with clinical stage III breast cancer and underwent pretreatment (18)F-FDG PET/CT were retrospectively analyzed. The (18)F-FDG PET/CT scans were prospectively reviewed by two board-certified nuclear medicine physicians in a blinded manner. The intensities of IMNs were graded into four categories (no activity and lower, similar, and higher activities than that of the mediastinal blood pool). IMNs were measured from the combined CT (largest diameter of the short axis). Histologic data of the IMNs were obtained by ultrasonography-guided fine-needle aspiration biopsy or surgical excision. The PPV was calculated for pathologically confirmed IMNs. Visual grade, maximum standardized uptake values (SUVmax), and sizes were analyzed according to the pathology results.

RESULTS

There were 249 clinical stage III breast cancer patients (age 48.0 ± 10.1 years, range 26-79 years) who had undergone initial (18)F-FDG PET/CT prior to treatment. Excluding 33 cases of stage IV breast cancer, 62 of 216 patients had visible IMNs on (18)F-FDG PET/CT, and histologic confirmation was obtained in 31 patients. There were 27 metastatic and four nonmetastatic nodes (PPV 87.1%). Metastatic nodes mostly presented with visual grade 3 (83.9%), and SUVmax and size were 3.5 ± 4.3 and 5.6 ± 2.0 mm, respectively.

CONCLUSION

(18)F-FDG PET/CT has a high PPV for IMN metastasis in clinical stage III breast cancer, indicating the possibility of metastasis in IMNs with FDG uptake similar to/lower than that of the blood pool or small-sized nodes.

Discovery of Q203, a potent clinical candidate for the treatment of tuberculosis

New therapeutic strategies are needed to combat the tuberculosis pandemic and the spread of multidrug-resistant (MDR) and extensively drug-resistant (XDR) forms of the disease, which remain a serious public health challenge worldwide. The most urgent clinical need is to discover potent agents capable of reducing the duration of MDR and XDR tuberculosis therapy with a success rate comparable to that of current therapies for drug-susceptible tuberculosis. The last decade has seen the discovery of new agent classes for the management of tuberculosis, several of which are currently in clinical trials. However, given the high attrition rate of drug candidates during clinical development and the emergence of drug resistance, the discovery of additional clinical candidates is clearly needed. Here, we report on a promising class of imidazopyridine amide (IPA) compounds that block Mycobacterium tuberculosis growth by targeting the respiratory cytochrome bc1 complex. The optimized IPA compound Q203 inhibited the growth of MDR and XDR M. tuberculosis clinical isolates in culture broth medium in the low nanomolar range and was efficacious in a mouse model of tuberculosis at a dose less than 1 mg per kg body weight, which highlights the potency of this compound. In addition, Q203 displays pharmacokinetic and safety profiles compatible with once-daily dosing. Together, our data indicate that Q203 is a promising new clinical candidate for the treatment of tuberculosis.

Antioxidant activity and inhibition of lipid peroxidation in germinating seeds of transgenic soybean expressing OsHGGT

Tocochromanols are potent lipid-soluble antioxidants and essential nutrients for human health. Genetic engineering techniques were used to develop soybeans with enhanced vitamin E levels, including tocotrienols, which are not found in soybean. The gene encoding rice homogentisate geranylgeranyl transferase (HGGT) was overexpressed in soybeans using seed-specific and constitutive promoters. The association between abundance of vitamin E isomers and antioxidant activity was investigated during seed germination. With the exception of β-tocotrienol, all vitamin E isomers were detected in germinating seeds expressing OsHGGT. The antioxidant properties of germinating seed extracts were determined using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azinobis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radicals and lipid peroxidation (TBARS). Compared with intact wild-type seeds, transgenic seeds showed increases in radical scavenging of 5.4-17 and 23.2-35.3% in the DPPH and ABTS assays, respectively. Furthermore, the lipid peroxidation levels were 2.0-4.5-fold lower in germinating seeds from transgenic lines than in wild-type seeds. Therefore, it appears that the antioxidant potential of transgenic oil-producing plants such as soybean, sunflower, and corn may be enhanced by overexpressing OsHGGT during seed germination.

High content screening identifies decaprenyl-phosphoribose 2' epimerase as a target for intracellular antimycobacterial inhibitors

A critical feature of Mycobacterium tuberculosis, the causative agent of human tuberculosis (TB), is its ability to survive and multiply within macrophages, making these host cells an ideal niche for persisting microbes. Killing the intracellular tubercle bacilli is a key requirement for efficient tuberculosis treatment, yet identifying potent inhibitors has been hampered by labor-intensive techniques and lack of validated targets. Here, we present the development of a phenotypic cell-based assay that uses automated confocal fluorescence microscopy for high throughput screening of chemicals that interfere with the replication of M. tuberculosis within macrophages. Screening a library of 57,000 small molecules led to the identification of 135 active compounds with potent intracellular anti-mycobacterial efficacy and no host cell toxicity. Among these, the dinitrobenzamide derivatives (DNB) showed high activity against M. tuberculosis, including extensively drug resistant (XDR) strains. More importantly, we demonstrate that incubation of M. tuberculosis with DNB inhibited the formation of both lipoarabinomannan and arabinogalactan, attributable to the inhibition of decaprenyl-phospho-arabinose synthesis catalyzed by the decaprenyl-phosphoribose 2′ epimerase DprE1/DprE2. Inhibition of this new target will likely contribute to new therapeutic solutions against emerging XDR-TB. Beyond validating the high throughput/content screening approach, our results open new avenues for finding the next generation of antimicrobials.

Tuberculosis is still a major threat to global health. The disease in humans is caused by a bacterium, Mycobacterium tuberculosis, and treatment of an infected individual requires more than six months of chemotherapy. Because such a long course of treatment is required, compliance is low, which can result in the development of multidrug resistant strains (MDR-TB) and even extremely resistant strains (XDR-TB). Identifying new drug targets and potential lead therapeutic compounds are needed to combat MDR-XDR-TB. We developed a new type of assay based on the visualization of mycobacterium replication within host cells and applied it for the search of compounds that are able to chase the pathogen from its hideout. As a result, we found 20 new series of drug candidates that are effective against the bacilli in its hiding place, potentially addressing a crucial aspect in the resilience of the disease. We also showed that one series of compounds acts by inhibiting a key enzyme required for the synthesis of an essential component from the mycobacterial cell wall that is not targeted by any of the commercially available antituberculosis drugs. Altogether, our results pave the way for development of the next generation of antibacterial agents.

First Report of Soybean Pod and Stem Blight Caused by Diaporthe phaseolorum var. sojae in Taiwan

Genera, Diaporthe and Phomopsis, from an important pathogenic complex of soybean (Glycine max) throughout the world, cause reductions in plant stands, yield, and seed health and quality (1). In a study of the Diaporthe/Phomopsis complex in Taiwan in March 2008, four stem samples with black fruiting structures in linear rows on senescent soybean were collected from the research fields at AVRDC, Shanhua, Tainan, Taiwan. Unidentified fungal isolates were obtained by surface disinfection of infected stems and plating excised tissues on potato dextrose agar (PDA). Colonies of the isolates showed ropelike white mycelia with yellowish tonalities. Small and scattered black stromata were observed frequently in the medium. Mutic pycnidia were found solitarily or aggregated in conidiomata on PDA plates after 10 days of incubation at 24°C with a 12-h photoperiod with near-UV light. All isolates produced α-conidia that measured 8.78 × 3.32 (7.00 to11.00 × 3.00 to 4.00) μm, and sporadically, β-conidia of 30.58 × 0.85 (26.00 to 33.00 × 0.60 to 1.20) μm. Perithecia were not observed in the collected stem samples or the fungal cultures on PDA. Restriction fragment length polymorphism patterns of the PCR products amplified by ITS₄ and ITS₅ primers for all isolates were identical to the patterns reported for Diaporthe phaseolorum var. sojae (3). Thus, all isolates were identified as D. phaseolorum var. sojae on the basis of morphologic and genetic characteristics (2,3). Pathogenicity was confirmed through inoculations during the V2 growth stage of soybean seedlings by atomizing conidial suspensions (1 × 10⁷ α-conidia/ml) of each isolate on soybean seedlings as well as by injecting the inoculum into soybean stems separately. Four plants in each of three replications were inoculated for each method and six noninoculated plants served as controls. Plants were incubated in a growth chamber at 25°C and maintaining relative humidity at 100% by a humidifier for 48 h in darkness; thereafter, plants were maintained in the greenhouse at temperatures ranging from 23 to 34°C. Seven days after inoculation, red-brown leaf spots and coalescent lesions were observed on seedlings atomized by inoculum suspensions, as well as brown lesions and black pycnida in linear rows observed on plants inoculated by stem injection. No symptoms were observed on noninoculated plants. The fungal isolates obtained from inoculated soybeans were morphologically identical to those used as inoculum. The pathogenicity test was repeated twice. To our knowledge, this is the first explicit report identifying the causal agent of soybean pod and stem blight in Taiwan. The vouchers of infected specimens are available at AVRDC-The World Vegetable Center. Reference: (1) R. P. Mulrooney. Plant Dis. 70:600, 1988. (2) R. N. Pioli et al. Phytopathology 93:136, 2003. (3) A. W. Zhang et al. Phytopathology 88:1306, 1998.

The assessment of ankle joint forces during the postural balance control movement

The purpose of this study was to calculate three-dimensional angular displacements, moments and joint reaction forces of the ankle joint during the waist pulling, and then, we assessed the reaction forces and bone-on-bone forces within ankle joint during postural balance control movement. With experiments and MATLAB simulation we could calculate ankle joint kinematic and kinetic data. The results presented in this study will be useful data for understanding the injury mechanism of ankle joint during postural balance control.

High glucose dialysis solutions increase synthesis of vascular endothelial growth factors by peritoneal vascular endothelial cells

OBJECTIVE

Increased peritoneal vasculature has been reported in long-term peritoneal dialysis (PD), and vascular endothelial growth factors (VEGFs) have been found in dialysate. High concentrations of glucose or lactate, glucose degradation products (GDPs), and low pH of dialysis solutions are all possible factors in increased peritoneal VEGF synthesis. In this study, we investigated the effects of high glucose dialysis solutions on VEGF synthesis by peritoneal vascular endothelial cells (PVECs).

METHODS

The PVECs were isolated from rat omentum and were incubated for 4 hours in three different culture media [M199 media (control), conventional dialysis solutions containing 4.25% glucose diluted with an equal volume of M199 media (HGD), and M199 media containing 118 mmol/L mannitol as an osmolar control (mannitol)]. Levels of VEGF protein in the culture supernatant were measured by ELISA, and mRNA expression was determined by Northern blot analysis. Data are presented as percent of control.

RESULTS

After incubation for 4 hours, the number of cells did not differ between the 3 groups. Levels of VEGF in culture supernatant were significantly higher in the HGD group (124% +/- 19%, p = 0.006) as compared with the control and mannitol (85% +/- 10%) groups. The mRNA expression of VEGF appeared to be higher in the HGD group (128% +/- 49%) than in the control and mannitol (94% +/- 18%) groups.

CONCLUSION

High glucose dialysis solutions increased VEGF synthesis by PVECs. The relationship between VEGF synthesis by PVECs and neovascularization of the peritoneum observed in long-term peritoneal dialysis patients has to be studied further.

Perception of wheezing in the elderly asthmatics

BACKGROUND

In elderly asthmatics, underdiagnosis is one of the important features. The main reason for underdiagnosis is thought to be a low frequency in complaining of symptoms due to the reduction of intellectual recognition and physical activity. Among the various symptoms, wheezing is the principal clue in diagnosing bronchial asthma, and decreased complaints for wheezing are also noted in elderly asthmatics. The objective of this study is to determine if less complaints of wheezing in elderly asthmatic is due to decrease in the development of wheezing.

METHODS

61 young (20-39 years old), 68 middle-aged (40-59 years old) and 65 elderly (older than 60 years old) stable asthmatic subjects were studied (each group shall be called, hereafter, Young Group, Middle-aged Group and Old Group, respectively). During the methacholine induced airway narrowing, lung auscultation and questionnaire survey about presence and perception of wheezing were conducted in 194 asthmatics.

RESULTS

One hundred and sixty-nine patients (87%) developed wheezing during the methacholine induced airway obstruction. The frequency of wheezing during the methacholine challenge was found to be comparable among the groups. The methacholine concentration, % fall in FEV1, and FEV1 levels of the initial detection of wheezing were not different among the groups. Among the patients who developed wheezing, 47 patients (77%), 42 patients (61.8%) and 26 patients (40%) complained of wheezing in Young, Middle and Old Group, respectively.

CONCLUSION

In conclusion, the decreased perception of wheezing is a main factor for the low frequency of complaints of wheezing in elderly asthmatics.

Improvement of tagatose conversion rate by genetic evolution of thermostable galactose isomerase

To enhance the isomerization rate of galactose into tagatose, a thermostable galactose isomerase, which was isolated from bacteria growing in a hot spring, was genetically improved using the error-prone PCR method. From 500 mutant clones, a clone showing improved conversion activity was selected. The sequence of the selected clone had five amino acid changes: His(228)-->Asp, Gly(384)-->Asp, Ser(393)-->Thr, Lys(428)-->Asn and Asp(475)-->Lys. The improved galactose isomerase had an 11-fold higher reaction rate than the original.