Crystallization of high-amylose starch by the addition of plasticizers at low and intermediate concentrations

The antiplasticization effect of plasticizers (that is, polyols and monosaccharides) in starch films was investigated. Pea starch films were plasticized by various polyols and monosaccharides at the levels of 0% to 25% (w/w, plasticizer/starch). After 14 d of storage at 50% relative humidity, the crystallinity of pea starch films increased with increasing concentration of plasticizers from 0% to 20%. Accordingly, moisture content, water vapor permeability, oxygen permeability, and elongation decreased with increasing plasticizer concentration from 0% to 20%, showing the antiplasticization effect. The addition of plasticizers above 20% reduced the crystallinity of starch films, consequently showing the plasticization effect. The results showed that the addition of the plasticizers facilitated the crystallization of the polymer chains through the antiplasticization phenomenon at the concentration range below 15%. Above 20%, plasticizers performed the conventional plasticization effect. Each plasticizer had different critical concentration where the antiplasticization was converted to plasticization.

Metabolic syndrome and quality of life (QOL) using generalised and obesity-specific QOL scales

OBJECTIVES

We investigated the association between metabolic syndrome (MS) and health-related quality of life (HRQOL) assessed using generalised and obesity-specific QOL instruments.

METHODS

We recruited 456 outpatients [age: 19-81 years, body mass index (BMI): 16.3-36.7 kg/m2] in the primary care division from 12 general hospitals in Korea. HRQOL was measured using EuroQol comprising the health states descriptive system (EQ-5D) and visual analogue scale (EQ-VAS) as a general instrument. The Korean Obesity-related QOL scale (KOQOL) composed of six domains was used as a disease-specific QOL instrument. MS was defined on the basis of International Diabetes Federation (IDF) criteria with Korean-specific waist circumference cutoffs (men: 90 cm, women: 85 cm).

RESULTS

Subjects with MS displayed significantly higher impairment of EQ-5D and KOQOL. Binary logistic regression analysis of MS patients with controls for age, gender, smoking, alcohol, exercise, education, income, marital status and medication history disclosed odds ratio (OR) values of 2.13 (1.33-3.41) for impaired total KOQOL, 2.07 (1.31-3.27) for impaired physical health, 1.63 (1.03-2.60) for impaired work-related health, 2.42 (1.45-4.04) for impaired routine life, 2.08 (1.27-3.40) for impaired sexual life and 2.56 (1.59-4.11) for diet distress. Among the EQ-5D dimensions, only pain/discomfort displayed a significantly increased OR of 1.60 (1.01-2.56) in MS group.

CONCLUSIONS

Subjects with MS displayed a significantly impaired HRQOL compared with those without MS. MS and HRQOL were more strongly associated in obesity-specific QOL than in generalised QOL.

Coating of peanuts with edible whey protein film containing alpha-tocopherol and ascorbyl palmitate

Physical properties of whey protein isolate (WPI) coating solution incorporating ascorbic palmitate (AP) and alpha-tocopherol (tocopherol) were characterized, and the antioxidant activity of dried WPI coatings against lipid oxidation in roasted peanuts were investigated. The AP and tocopherol were mixed into a 10% (w/w) WPI solution containing 6.7% glycerol. Process 1 (P1) blended an AP and tocopherol mixture directly into the WPI solution using a high-speed homogenizer. Process 2 (P2) used ethanol as a solvent for dissolving AP and tocopherol into the WPI solution. The viscosity and turbidity of the WPI coating solution showed the Newtonian fluid behavior, and 0.25% of critical concentration of AP in WPI solution rheology. After peanuts were coated with WPI solutions, color changes of peanuts were measured during 16 wk of storage at 25 degrees C, and the oxidation of peanuts was determined by hexanal analysis using solid-phase micro-extraction samplers and GC-MS. Regardless of the presence of antioxidants in the coating layer, the formation of hexanal from the oxidation of peanut lipids was reduced by WPI coatings, which indicates WPI coatings protected the peanuts from oxygen permeation and oxidation. However, the incorporation of antioxidants in the WPI coating layer did not show a significant difference in hexanal production from that of WPI coating treatment without incorporation of antioxidants.

Sorption isotherm and plasticization effect of moisture and plasticizers in pea starch film

Pea starch films were produced with various plasticizers (glucose, fructose, mannose, sorbitol, and glycerol). Effects of plasticizer content (4.34 to 10.87 mmol/g of dry starch) and storage relative humidity (RH) (11.3% to 75.4%) on moisture content (MC), tensile strength (TS), elongation (E), modulus of elasticity (EM), and water vapor permeability (WVP) were evaluated using response surface methodology. MC was influenced strongly by RH. Glycerol-plasticized films had the highest MC, indicating that water molecules played a more important role in plasticizing starch films. Monosaccharide-plasticized films and polyol-plasticized films had similar TS values. However, monosaccharide-plasticized films had higher E values and lower EM values than polyol-plasticized films, meaning monosaccharides had better efficiency in plasticizing starch films. Recrystallization happened in glucose- and sorbitol-plasticized films when they were stored in high RH. Sorption isotherm studies showed the similar adsorption and desorption profiles for all 3 monosaccharide-plasticized films and a hysteresis. The Flory-Huggius model fitted experimental data best for starch films, while the BET model fitted the data marginally.

Role for the NR2B subunit of the N-methyl-D-aspartate receptor in mediating light input to the circadian system

Light information reaches the suprachiasmatic nucleus (SCN) through a subpopulation of retinal ganglion cells that utilize glutamate as a neurotransmitter. A variety of evidence suggests that the release of glutamate then activates N-methyl-D-aspartate (NMDA) receptors within the SCN and triggers a signaling cascade that ultimately leads to phase shifts in the circadian system. In this study, we first sought to explore the role of the NR2B subunit in mediating the effects of light on the circadian system of hamsters and mice. We found that localized microinjection of the NR2B subunit antagonist ifenprodil into the SCN region reduces the magnitude of light-induced phase shifts of the circadian rhythm in wheel-running activity. Next, we found that the NR2B message and levels of phospho-NR2B vary with time of day in SCN tissue using semiquantitative real-time polymerase chain reaction and western blot analysis, respectively. Functionally, we found that blocking the NR2B subunit with ifenprodil significantly reduced the magnitude of NMDA currents recorded in SCN neurons. Ifenprodil also significantly reduced the magnitude of NMDA-induced Ca2+ changes in SCN cells. Together, these results demonstrate that the NR2B subunit is an important component of NMDA receptor-mediated responses within SCN neurons and that this subunit contributes to light-induced phase shifts of the mammalian circadian system.

Visceral adipose tissue as a predictor for metabolic risk factors in the Korean population

AIMS

Visceral adipose tissue (VAT) accumulation is closely associated with an increased risk of cardiovascular disease. We have investigated the appropriate VAT cut-off values for predicting metabolic risk factors in the Korean population.

METHODS

We assessed 276 men and 540 women aged 17-69 years who were undergoing regular health examinations. Anthropometry, metabolic risk factors and VAT area determined by computed tomography were measured. Receiver-operating characteristic (ROC) analysis was used to define VAT cut-off points for metabolic risk factors.

RESULTS

Based on the first quintile of VAT, the odds ratios for having metabolic risk factors increased significantly with each VAT quintile in both men and women. Using ROC analysis, the appropriate VAT cut-offs for metabolic risk factors were 100 cm(2) in men and 70 cm(2) in women. Regression lines indicated that, in men, a VAT of 100 cm(2) corresponded to a waist circumference of 88.1 cm and a body mass index (BMI) of 24.9 kg/m(2); in women, a VAT of 70 cm(2) corresponded to a waist circumference of 84.0 cm and a BMI of 25.1 kg/m(2).

CONCLUSION

VAT cut-offs of 100 cm(2) in men and 70 cm(2) in women are useful for defining visceral obesity in Korean subjects. These VAT cut-offs were validated by the ethnic-specific cut-offs for waist circumference and BMI for Korean individuals.

Extrusion of pea starch containing lysozyme and determination of antimicrobial activity

Pea starch, which has inherently good gel strength, was used as the source material for manufacturing a biodegradable and bioactive packaging material. Extrudates containing 99% pea starch and 1% lysozyme were produced under various extrusion conditions (high and low shear screw configurations, 30% to 40% moisture contents, 70 to 150 degrees C die temperatures). The physical and mechanical properties of the extrudates were determined through various expansion indices, piece and cell wall solid density, compression, and 3-point bending tests. The expansion of extrudates increased with an increase in die temperature, whereas increasing moisture content had the opposite effect. Extrudate densities decreased as extrusion temperature increased, whereas lower moisture content in the extrudate dough decreased extrudate densities. The elastic modulus and fracture strengths were highly correlated in a power-law fashion to relative density, showing that the mechanical properties of extrudates were dependent on solid density and foam structure. Up to 48% of the initial lysozyme activity was recovered from the extruded pea starch matrix. The lysozyme released from extrudates showed an inhibition zone against Brochotrix thermosphacta B2. Extruded pea starch matrix containing lysozyme has potential application as an edible and biodegradable packaging material with antimicrobial activity.

Human hair growth enhancement in vitro by green tea epigallocatechin-3-gallate (EGCG)

Green tea is a popular worldwide beverage, and its potential beneficial effects such as anti-cancer and anti-oxidant properties are believed to be mediated by epigallocatechin-3-gallate (EGCG), a major constituent of polyphenols. Recently, it was reported that EGCG might be useful in the prevention or treatment of androgenetic alopecia by selectively inhibiting 5alpha-reductase activity. However, no report has been issued to date on the effect of EGCG on human hair growth. This study was undertaken to measure the effect of EGCG on hair growth in vitro and to investigate its effect on human dermal papilla cells (DPCs) in vivo and in vitro. EGCG promoted hair growth in hair follicles ex vivo culture and the proliferation of cultured DPCs. The growth stimulation of DPCs by EGCG in vitro may be mediated through the upregulations of phosphorylated Erk and Akt and by an increase in the ratio of Bcl-2/Bax ratio. Similar results were also obtained in in vivo dermal papillae of human scalps. Thus, we suggest that EGCG stimulates human hair growth through these dual proliferative and anti-apoptotic effects on DPCs.

Rapid and reliable method for quantification of Mycobacterium paratuberculosis by use of the BACTEC MGIT 960 system

A simple method for the enumeration of viable Mycobacterium paratuberculosis cells was developed and evaluated using the MGIT 960 culture system. For each of 12 M. paratuberculosis strains isolated from either cattle or humans, single-cell suspensions of M. paratuberculosis cells were adjusted to an optical density at 600 nm of 1.00 (10(7.6) to 10(8.2) cells/ml), and serial dilutions were prepared. Standard curves were established by relating the MGIT time-to-detection data to the log10 CFU for these suspensions using standard plate counting and BACTEC 460 results as reference methods. Universal and strain-specific standard quantification curves were generated. A one-phase exponential decay equation best fit the universal standard curve and strain-specific curves (R2 of 0.96 and >0.99, respectively). Two subgroups within the universal curves were distinguished: one for laboratory-adapted strains and the other for recently isolated low-passage bovine strains. The predictive errors for log(10) estimations using the universal standard curve, each subgroup's standard curve, and strain-specific curves were +/-0.87, +/-0.45, and +/-0.31 log10 units, respectively. CFU estimations by all three standard curves were highly reproducible, regardless of the M. paratuberculosis strain or inoculum volume. In comparison with the previously described BACTEC 460 M. paratuberculosis counting method, quantification with MGIT 960 was less expensive, more rapid, more accurate, and more sensitive (<10 CFU). This MGIT counting method has broad applications for studies requiring the quantification of viable M. paratuberculosis cells, such as drug susceptibility testing or environmental survival studies.

Suitability of pea starch and calcium alginate as antimicrobial coatings on chicken skin

The effect of incorporating trisodium phosphate (TSP) in pea starch (PS) and acidified sodium chlorite (ASC) in calcium alginate upon the antimicrobial activity of TSP and ASC was studied against a 3-strain cocktail of Salmonella inoculated on chicken skin. The influence of polymer coating concentration on skin pH, coating-skin adhesion, and coating absorption upon antimicrobial performance were investigated. Aqueous solutions of 0.5 to 4.8% (wt/vol) PS were prepared with 10% (wt/vol) TSP (PS + TSP coating), and alginate + ASC coatings contained 1% (wt/vol) calcium chloride in 1,200 ppm of ASC mixed with an aqueous solution of 0.5, 1.0, or 1.5% (wt/vol) sodium alginate. Coating drops (10 microL) were placed on chicken skin thighs, and the angle formed by the tangent of the liquid surface at the skin interface (contact angle) was measured using a digital camera to assess coating-skin adhesion. Excised skins were mounted in a ring holder, and 5 mL of the coatings was applied to the skin. Weight changes in the skins that were related to coating absorptiveness were recorded. The TSP dissolved in 3.5% PS and ASC in 1% alginate reduced Salmonella by 1.6 log cfu/g and 1.4 log cfu/g, respectively, within 24 h. These reductions were significantly greater than those caused by TSP or ASC alone in water for up to 120 h. In coatings, TSP and ASC caused significant elevation or reduction of skin surface pH for up to 120 h, respectively. The TSP destabilized PS with 88% of the coating having dripped from the skin 1 h later. Coatings with 0.5% PS were absorbed quickly by the skin and had high skin adhesion, whereas those with >3.5% PS had low skin adhesion and slow absorption. Alginate coatings with or without ASC were stable, and about 50% of the coating weight was retained at 120 h. The latter coatings appeared to have low absorptiveness because the skin gained approximately 1.0% of its weight within 60 min following application. These findings indicate that effects of the agents in coatings on skin pH, the extent of coating adhesion, and absorption may contribute to overall antimicrobial behaviors.

Prevalence and trends of metabolic syndrome in Korea: Korean National Health and Nutrition Survey 1998-2001

BACKGROUND

Metabolic syndrome (MetS) is a major international health problem. Limited information is available about the prevalence of MetS in Asia, especially in Korea.

OBJECTIVE

To examine the prevalence and trends of MetS in a Korean population. In addition, we investigated the risk factors associated with MetS.

DESIGN AND PARTICIPANTS

A total of 7445 participants aged >/=20 years from the Korean National Health and Nutrition Survey (KNHNS) 1998 and 5964 participants from the KNHNS 2001 were included in this analysis. The KNHNS is a cross-sectional health survey of a nationally representative sample of the Korean population. The prevalence of MetS was determined using the National Cholesterol Education Program Adult Treatment Panel III criteria and the Asia-Pacific criteria for obesity based on waist circumference (APC-WC).

RESULTS

Using the ATP III criteria, the age-adjusted prevalence of MetS among Korean adults was 15.7% (13.7% male, 17.8% female) in 1998 and 14.4% (13.0% male, 16.2% female) in 2001. Using the APC-WC criteria, the prevalence was 21.6% (19.4% male, 23.9% female) in 1998 and 21.4% (20.1% male, 23.4% female) in 2001. Of the five MetS components, increasing trends were found between 1998 and 2001 in the prevalence of hypertriglyceridaemia, low high-density lipoprotein cholesterol and central obesity for both men and women. Age, sex, body mass index and a family history of diabetes were associated with MetS.

CONCLUSIONS

These results from a representative sample show that MetS is common in Korean adults. A systemic public health programme is required to prevent future increases in diabetes and cardiovascular complications.

7-Ketocholesterol enhances 1-methyl-4-phenylpyridinium-induced mitochondrial dysfunction and cell death in PC12 cells

The present study investigated the promoting effect of oxysterol 7-ketocholesterol against the cytotoxicity of 1-methyl-4-phenylpyridinium (MPP(+)) in differentiated PC12 cells. 7-Ketocholesterol significantly enhanced the MPP(+)-induced nuclear damage, decrease in the mitochondrial transmembrane potential, cytosolic accumulation of cytochrome c, activation of caspase-3, increase in the formation of reactive oxygen species and depletion of GSH. N-Acetylcysteine, ascorbate, trolox, carboxy-PTIO and Mn-TBAP reduced the cytotoxic effect of MPP(+) in the presence of 7-ketocholesterol. The results indicate that 7-ketocholesterol shows a synergistic effect against the cytotoxic effect of MPP(+). 7-Ketocholesterol may enhance the MPP(+)-induced viability loss in PC12 cells by promoting the mitochondrial membrane permeability change, release of cytochrome c and subsequent activation of caspase-3, which is associated with the increased formation of reactive oxygen species and depletion of GSH. The findings suggest that 7-ketocholesterol as a promoting agent for the formation of mitochondrial permeability transition may enhance the toxic neuronal cell injury.

Prevalence of diabetes and impaired fasting glucose in Korea: Korean National Health and Nutrition Survey 2001

OBJECTIVE

The purpose of this study was to estimate the prevalence of diabetes and impaired fasting glucose (IFG) and their association with risk factors in the Korean population.

RESEARCH DESIGN AND METHODS

The Korean National Health and Nutrition Survey 2001 was a nationally representative survey with a stratified multistage sampling design. Data from a comprehensive questionnaire, a physical examination, and blood tests were obtained from 5,844 Korean adults (2,513 men and 3,331 women) aged >20 years.

RESULTS

The age-adjusted prevalence of diabetes in this Korean population was 7.6%, and the age-adjusted prevalences of previously diagnosed diabetes and newly diagnosed diabetes were 4.4 and 3.3%, respectively (fasting plasma glucose > or = 7.0 mmol/l). Overall, these results indicate that 8.1% or 1.4 million Korean men and 7.5% or 1.3 million Korean women have diabetes. The age-adjusted prevalence of IFG was 23.9%, using the new American Diabetes Association criteria (fasting plasma glucose 5.6-6.9 mmol/l). Diabetes prevalence increased with age and peaked in the oldest age-group; however, IFG prevalence did not show the same trend. Diabetes was found to be associated with age, BMI, blood pressure, triglyceride, HDL cholesterol, education levels, alcohol consumption, exercise, and a family history of diabetes.

CONCLUSIONS

This study shows that diabetes and IFG are common in Korea, and about one-half of diabetes cases remain undiagnosed. These results emphasize the need to develop an urgent public program to improve the detection, prevention, and treatment of diabetes.

Concurrent chemoradiotherapy in patients with nasopharyngeal cancer: prognostic significance of low expression of bax

A randomized trial has demonstrated that concurrent chemoradiotherapy (CRT) is superior to radiotherapy (RT) alone in locally advanced nasopharyngeal cancer (NPC). Our study comprise 35 patients with locally advanced NPC (stage I: 1, II: 12, III: 7, IV: 15) with 1 cycle of induction chemotherapy (5-fluorouracil 1,000 mg/m(2)/day and cisplatin 20 mg/m(2)/day, days 1- 4) followed by concurrent CRT starting on day 22. Concurrent CRT consisted of RT (70 Gy/35 fractions for 7 weeks) with cisplatin 20 mg/m(2)/day for 4 days on weeks 1, 4, 7 of RT. Complete response (CR) was achieved in 33 patients (94%). Four-year progression-free survival (PFS) and overall survival (OS) of all patients were 57% and 65%, respectively. In analysis of prognostic factors, low expression of bax was the most significant independent predictor of poor prognosis in both PFS (p=0.002) and OS (p=0.008). In conclusion, the outcome of patients treated with this combined therapeutical modality appears to be comparable with that of Intergroup 0099 trial with high CR rate. Low expression of bax was significantly associated with poor PFS and OS.

Use of mustard flour to inactivate Escherichia coli O157:H7 in ground beef under nitrogen flushed packaging

This study was undertaken to determine whether the glucosinolates naturally present in non-deheated mustard flour could serve as a source of allyl and other isothiocyanates in sufficient quantity to kill Escherichia coli O157:H7 inoculated in ground beef at three different levels, during refrigerated storage of the meat under nitrogen. Mustard flour was mixed at 5%, 10% or 20% (w/w) with freshly ground beef, then the beef was inoculated with a cocktail of five strains of E. coli O157:H7 at either 3, 6 or < or =1.6 log10 cfu/g. The ground beef was formed into 100 g patties and each was placed in a bag of Nylon/EVOH/PE, which was back-flushed with 100% N2, heat-sealed and stored at 4 degrees C for < or =21 days. During storage, the allyl isothiocyanate (AIT) levels in package headspaces were determined by gas liquid chromatography. By 21 days, the levels present in treatments were not significantly different. After 21 days storage, there were 0.5, 3 and 5.4 log10 decreases in numbers of E. coli O157:H7 from the initial levels of 6 log10 cfu/g in meat containing 5%, 10% and 20% mustard flour, respectively. When inoculated at 3 log10 cfu/g, E. coli O157:H7 was reduced to undetectable levels after 18, 12 and 3 days with 5%, 10% and 20% mustard flour, respectively. When immunomagnetic separation (IMS) was used for E. coli recovery following its inoculation at < or =1.6 log10 cfu/g, 5% mustard did not completely eliminate the pathogen from ground beef stored for 6 days. The natural microflora of the ground beef which developed in vacuum packages was unaffected by the addition of 5% mustard flour but some inhibition was found at higher concentrations. Sensory evaluation of the cooked ground beef showed that there were no significant differences in the acceptability of meat treated with 5 or 10% mustard flour. However, panelists could distinguish untreated controls from mustard treatments, but considered the mustard-treated meat to be acceptable. These results showed that it is possible to use mustard flour at levels of >5-10% to eliminate E. coli O157:H7 from fresh ground beef.

Inactivation of Escherichia coli O157:H7 in packaged ground beef by allyl isothiocyanate

Commercial allyl isothiocyanate (AIT) was examined for its ability to reduce numbers of Escherichia coli O157:H7 inoculated in fresh ground beef packaged under nitrogen and stored refrigerated or frozen. A five-strain cocktail of E. coli O157:H7 containing 3 or 6 log10 cfu/g was inoculated into 100 g ground beef and formed into 10x1-cm patties. A 10-cm diameter filter paper disk treated with AIT suspended in sterile corn oil was placed on top of a single patty. One patty and paper disk were placed in a bag of Nylon/EVOH/PE with O2 permeability of 2.3 cm3 m(-2) 24 h atm at 23 degrees C. The bags were back-flushed with 100% nitrogen, heat-sealed and stored at 10, 4 and -18 degrees C for 8, 21 or 35 days, respectively. During storage, the AIT levels in the package headspaces were determined by gas liquid chromatography, and mesophilic bacteria and E. coli O157:H7 were counted. The mesophilic aerobic bacteria in ground beef patties were largely unaffected by the addition of AIT. At an initial population of 3 log10 cfu/g, E. coli O157:H7 was reduced by AIT to undetectable levels after 18 days at 4 degrees C or 10 days at -18 degrees C. In samples inoculated with 6 log10 cfu/g, a >3 log10 reduction of E. coli O157:H7 was observed after 21 days at 4 degrees C, while a 1 log10 reduction was observed after 8 and 35 days at 10 and -18 degrees C, respectively. The final AIT concentrations in the headspaces after storage at 10, 4, and -18 degrees C were 444, 456, and 112 microg/ml at 8, 21, and 35 days, respectively. Results showed that AIT can substantially reduce numbers of E. coli O157:H7 in fresh ground beef during refrigerated or frozen storage.

Use of a crush-reducing device to decrease crushing of suckling piglets by sows

Weanling pigs tend to avoid wind, and suckling piglets are thought to be more sensitive to wind than weanlings, owing to their thinner s.c. fat layer. We developed a crush-reducing device based on the anticipated behavior of suckling piglets toward wind and evaluated the performance of the device through field testing. The crush-reducing device consisted of six photo sensors, a controller, six solenoid valves, and an air compressor. In this study, 206 sows and their suckling piglets (Landrace xYorkshire) were investigated to ascertain the individual effects of several factors. Some of the newborn piglets were cross-fostered before the crush-reducing device was implemented. Litter weights were measured on d 0 and 4 to determine the influence of the crush-reducing device on the weights of suckling piglets. The crushing of suckling piglets by sows was affected by season (P < 0.01) and litter size (P < 0.05), but not by the parity of the sows; however, the number of crushed piglets per litter was less (P < 0.01) in the crush-reducing device group (0.05 +/- 0.02 crushed piglets/litter) than in the control group (0.23 +/- 0.04 crushed piglets/litter), regardless of litter size or season. The BW gain of suckling piglets did not differ between the control and the crush-reducing device groups. Based on these results, the crush-reducing device is expected to decrease the number of crushed piglets per litter without influencing the BW gain of suckling piglets, thereby greatly contributing to the productivity of pig breeders.

Nitrogen removal characteristics analyzed with gas and microbial community in thermophilic aerobic digestion for piggery waste treatment

In order to characterize the nitrogen conversion characteristics in a thermophilic aerobic digestion (TAD) system, a laboratory study has been conducted with the analysis of effluent gas and microbial community in the sludge samples. The lab TAD system was operated with HRT of 3 days and 60 degrees C. Based on the nitrogen mass balance, it has been found that about 2/3 of the daily load of nitrogen was converted to the gaseous form of nitrogen whereas cellular transformation and unmetabolized nitrogen accounted for about 1/3. Among the gaseous nitrogen transformation, significant amount of influent nitrogen had been converted to N2 gas (29% of influent N) and N2O (9% of influent N). Ammonia conversion was only 28% of influent N. The detection of N2O gas is a clear indication of the biological nitrogen reduction process in the thermophilic aerobic digester. No conclusive evidence for the existence of aerobic deammonification has been found. The microbial community analysis showed that thermophilic bacteria such as Bacillus thermocloacae, Bacillus sp. and Clostridial groups dominated in this TAD reactor. The diverse microbial community in TAD sludge may play an important role in removing both strong organics and nitrogen from piggery waste.

Wax moth, Galleria mellonella, high density lipophorin receptor: alternative splicing, tissue-specific expression, and developmental regulation

A lipophorin (Lp) receptor cDNA from the fat body of Galleria mellonella (Lepidoptera) was cloned and sequenced. This is the first result in this order, Lepidoptera. It showed the pattern of the VLDL receptor belonging to the LDL receptor family. Sequence homology with other Lp receptors in insects, Locusta migratoria and Aedes aegypti, was 70 and 61%, respectively and each domain was highly conserved. Polyclonal anti-Lp receptor antibody prepared against expressed Lp receptor fragment between ligand binding domain and EGF-precursor homology domain (R305-D549 of amino acid residues) specifically detected the Lp receptor. Through immuno-blotting, the Lp receptor of larval fat body has an approximate molecular mass of about 97 and 110 kDa under non-reducing and reducing conditions, respectively. This result was in agreement with that of the ligand-blotting. The variant Lp receptors were expressed in the fat body of G. mellonella; one is an Lp receptor which lacks 84 bp of O-linked sugar domain and the other is a full length form of the Lp receptor. Both forms were detected by the polyclonal anti-Lp receptor antibody. The Lp receptor from the fat body of G. mellonella was differently expressed depending on the tissue and the developmental stage with specific abundance in prepupal stage. A steroid hormone, 20-hydroxyecdysone (20-HE) plays a crucial role in insect development. With regards to this conception, day 1-2 last instar larvae were treated with 20-HE and drastic induction of the Lp receptor was observed 48 h after treatment. It was also observed that cholesterol caused an induction of the Lp receptor.

Differentiation of a Vero cell adapted porcine epidemic diarrhea virus from Korean field strains by restriction fragment length polymorphism analysis of ORF 3

A porcine epidemic diarrhea virus (PEDV) designated DR13 was isolated in Vero cells and serially passaged by level 100. The virus was titrated at regular intervals of the passage level. Open reading frame (ORF) 3 sequences of the virus at passage levels 20, 40, 60, 80, and 100 were aligned and compared using a computer software program. Suitability of the restriction fragment length polymorphism (RFLP) analysis for differentiating the virus from other Korean field strains was investigated. The DR13 field isolate was successively adapted in Vero cells as observed through polymerase chain reaction (PCR) and titration of the virus. RFLP analysis identified change in cleavage sites of HindIII and Xho II from passage levels 75 and 90, respectively; these RFLP patterns of ORF 3 differentiated the Vero cell-adapted virus from its parent strain, DR13, and 12 other strains of PEDV studied. The cell adapted DR13 was tested for its pathogenicity and immunogenicity in piglets and pregnant sows. The results indicated that cell adapted DR13 revealed reduced pathogenicity and induced protective immune response in pigs. Differentiation between highly Vero cell-adapted virus and wild-type virus could be the marker of adaptation to cell culture and a valuable tool for epidemiologic studies of PEDV infections. The results of this study supported that the cell attenuated virus could be applied as a marker vaccine candidate against PEDV infection.

Use of quantum methods for a consistent approach to combustion modelling: hydrocarbon bond dissociation energies

An attempt has been made to use modern quantum methods to codify the data base concerning bond dissociation energies in hydrocarbons. Calculations have been performed using two hybrid DFT methods, the well-known B3LYP formalism and a newly developed alternative named KMLYP. CBS-Q has also been employed where possible. The combination of experimental uncertainty and theoretical limitations is less than completely satisfactory. However, within uncertainties that translate to a factor of two at 1500 K, many transferable quantities are elucidated. A hybrid method has been developed for the correction of DFT calculations using group additivity. Given that the philosophy behind this work is the understanding that all data bases must be optimised for specific applications, so that avoidance of large errors is more important than absolute precision, the results appear to be quite useful. We are particularly encouraged by the performance of the KMLYP method, given its ease of application to molecules of practical interest.

Nociceptin/orphanin FQ increases ANP secretion in neonatal cardiac myocytes

Nociceptin (N/OFQ) is a novel heptadecapeptide with an amino acid sequence similar to that of endogenous opioid peptide dynorphin A. Dynorphin have been reported to increase the secretion of atrial natriuretic peptide (ANP) via selective activation of kappa-opioid receptor in cultured atrial cardiocytes. The present study was designed to investigate the direct effect of N/OFQ on the ANP secretion in cultured neonatal rat cardiac myocytes via N/OFQ receptor (NOP) activation. The secretion of ANP from cultured neonatal cardiac myocytes was increased in terms of incubation time. N/OFQ, at a dose of 0.3, 1, 3, and 10 microM, caused increases in ANP secretion in a dose-dependent manner. The N/OFQ-induced ANP secretion was completely antagonized by antagonists of NOP, 1 microM each of [Phe1 (CH2-NH) Gly2] nociceptin (1-13)-NH2 ([FG]N/OFQ(1-13)NH2) or naloxone benzoylhydrazone. In contrast, naloxone (1 microM), the non-selective opioid receptor antagonist, did not alter ANP response to N/OFQ. N/OFQ at 3 microM inhibited basal and forskolin-stimulated cAMP production, which was partially antagonized with the pretreatment of [FG]N/OFQ(1-13)NH2. An increase in ANP secretion by N/OFQ was also partially blocked by the pretreatment of forskolin. Homologous competition studies in neonatal cardiomyocyte membranes revealed the presence of two distinct sites. The high affinity site (10.9 +/- 1.6 nM) was far less abundant than the low affinity site. Therefore, these results suggest that N/OFQ causes an increase in ANP secretion in cultured neonatal cardiac myocytes by decreasing cAMP through its binding sites.

Vitamin and mineral supplement use by healthy teenagers in Korea: motivating factors and dietary consequences

The use of vitamin and mineral supplements is increasing among young individuals. We surveyed 972 Korean teenagers (age 13-18 y ) for their use of vitamin/mineral supplements, their motivational factors, and the dietary consequences of supplement use. Prevalence of vitamin/mineral supplement use was 31%. Supplement use was highest in high-school students, females, individuals living in rural communities, and individuals from families in high socioeconomic strata. The supplements used most frequently were vitamin C, multivitamins, and vitamin A. Supplement users had a more positive view of the potential health benefits of supplements than did non-users. Most supplements were taken daily. Vitamins B2, B6, and C were the most frequently ingested nutrients from vitamin/mineral supplements. Vitamin/mineral intakes from supplements had a wide range, with mean intakes typically exceeding Korean or the U.S./Canadian recommended dietary allowances. Vitamins B12, B1, and C and iron comprised 2770%, 1930%, 1120%, and 1026%, respectively, of the Korean recommended dietary allowances. When nutrient intakes from the diet and supplements were combined, intakes of niacin, vitamin C, and iron exceeded the recommended upper-intake levels for these nutrients. The health benefits and risks of supplement use by teenagers merits further study.

The role of cytokines in the changes in bone turnover following bone marrow transplantation

Osteoporosis is a common disease among patients undergoing transplantation and a loss of bone mass is usually detected after bone marrow transplantation (BMT), particularly during the immediate post-BMT period. Post-BMT bone loss is primarily related to gonadal dysfunction and immunosuppression. Cytokines, especially interleukin 6, play an important role in the pathogenesis of postmenopausal osteoporosis. However, the pathogenetic role of cytokines in post-BMT bone loss is unknown and data on the changes of cytokines in accordance with bone turnover markers are scarce. The aim of this study was to assess the relationship between bone turnover markers and cytokines, which are regularly sampled at peripheral blood and bone marrow before and after allogeneic BMT. This prospective study included two analyses. The first was a study of 46 BMT recipients (M/F 28/18), examining the relationship between bone turnover markers and serum cytokines that were measured before and at 1 week, 2 weeks, 3 weeks, 4 weeks and 3 months after BMT. Serum intact parathyroid hormone was measured before BMT and at 3 weeks after BMT and its relation to other cytokines and bone turnover markers was evaluated. The second analysis was a study of 14 (M/F 9/5) of 46 patients in whom bone marrow plasma cytokines [interleukin 6 (IL-6) and tumor necrosis factor alpha (TNF-alpha)] were measured at 3 weeks after BMT. The relationship between bone marrow plasma cytokines and bone turnover markers was studied because bone marrow is the microenvironment where the real changes in bone turnover occur. Serum type I collagen carboxyterminal telopeptide (ICTP), a bone resorption marker, increased progressively until 4 weeks (peak) after BMT and then decreased thereafter. Serum osteocalcin, a bone formation marker, decreased progressively until 3 weeks after BMT and then increased thereafter. Serum IL-6 increased until 2 weeks after BMT and declined thereafter. Serum TNF-alpha increased until 3 weeks after BMT and declined thereafter. There was a significant positive correlation between serum ICTP and bone marrow IL-6 levels at 3 weeks after BMT, when a marked change in bone metabolism occurs following BMT. However, a correlation between bone turnover markers and bone marrow TNF-alpha or peripheral blood cytokines was not found. At 3 months after BMT, there was a significant negative correlation between the mean daily steroid dose and the serum osteocalcin level (r = -0.43, p < 0.05). The correlation between the Mean daily steroid dose and serum ICTP was also significant (r = 0.41, p < 0.05). Our data suggest that the progressive increase in bone resorption during the immediate post-BMT period is related to both steroid dose and the increase in bone marrow IL-6, which is a potent stimulator of bone resorption in vivo.

Attenuation of inhibitory effect of CNP on the secretion of ANP from hypertrophied atria

It has been shown that atrial natriuretic peptide (ANP) influences proliferation of cardiac cells. To define the possible role of C-type natriuretic peptide (CNP) in cardiac hypertrophy, the influence of CNP on the secretion of ANP was studied with the use of perfused nonbeating atria from monocrotaline-treated rats. Increases in atrial volume caused proportional increases in ANP secretion that were markedly suppressed by CNP (10(-6) M) in nonhypertrophied left atria and control right atria but not in hypertrophied right atria. However, increases in atrial volume and mechanically stimulated extracellular fluid (ECF) translocation by CNP were similar to those in the control group. Therefore, the secretion of ANP in terms of ECF translocation was decreased by CNP in nonhypertrophied left and control right atria but not in hypertrophied atria. However, the inhibitory effect of 8-bromo-cGMP on the secretion of ANP was observed in both atria. The cGMP productions from perfused hypertrophied atria and their membranes exposed to CNP were significantly lower than those from nonhypertrophied atria. No significant difference in natriuretic peptide receptor-B transcript was found. Therefore, attenuation of the inhibitory effect of CNP on the ANP secretion in hypertrophied atria may be due to lack of cGMP production. The results showing the relief of CNP-induced negative inhibition of ANP secretion by atrial hypertrophy suggest that CNP may be a contributing factor to delay the development of cardiac hypertrophy.