Effects of dietary levels of glycine, threonine and protein on threonine efficiency and threonine dehydrogenase activity in hepatic mitochondria of chicks

This study was carried out to evaluate the relationship between threonine (Thr) efficiency and Thr dehydrogenase (TDG) activity as an indicator of Thr oxidation on chicks fed with levels of diets (CP [17.5% and 21.5%] and Thr [3.8 and 4.7 g/100 g CP]; glycine [Gly][0.64% and 0.98%] and true digestible Thr [dThr] [0.45% and 0.60%]). Calculation of the Thr efficiency was based on N-balance data and an exponential N-utilization model, and TDG activity was determined as accumulation of aminoacetone and Gly during incubation of hepatic mitochondria. This study found that in the liver of chicks who received a diet containing up to 0.79% Thr (4.7 g Thr/100 g of CP) in the 17.5% CP diet, no significant (p>0.05) effect on TDG activity was observed. However, significantly (p = 0.014) increased TDG activity was observed with a diet containing 21.5% CP (4.7 g Thr/100 g of CP) and the efficiency of Thr utilization showed a significant (p = 0.001) decrease, indicating the end of the Thr limiting range. No significant (p>0.05) effect on the total TDG activity and accumulation of Gly was observed with addition of Gly to a diet containing 0.45% dThr. In addition, addition of Gly to a diet containing 0.60% dThr also did not result in a change in accumulation of Gly. Due to an increase in accumulation of aminoacetone, an elevated effect on total TDG activity was also observed. No significant (p>0.05) reduction in the efficiency of Thr utilization was observed after addition of Gly at the level of 0.45% dThr. However, significantly (p<0.001) reduced efficiency of Thr utilization was observed after addition of Gly at the level of 0.60% dThr. Collectively, we found that TDG was stimulated not only by addition of Thr and protein to the diet, but also by addition of Gly, and efficiency of Thr utilization was favorably affected by addition of Gly at the level near to the optimal Thr concentration. In addition, no metabolic requirement of Gly through the TDG pathway was observed with almost the same accumulation of Gly and a slight increase in TDG activity by addition of Gly. Thus, our findings suggest that determination of TDG activity and parameter of efficiency of Thr utilization may be useful for evaluation of dietary Thr level.

Effects of Dietary Fat Types on Growth Performance, Pork Quality, and Gene Expression in Growing-finishing Pigs

This study was performed to determine the effects of dietary fat sources, i.e., beef tallow, soybean oil, olive oil and coconut oil (each 3% in feed), on the growth performance, meat quality and gene expression in growing-finishing pigs. A total of 72 crossbred pigs (Landrace×Large White×Duroc) were used at 71±1 kg body weight (about 130 d of age) in 24 pens (320×150 cm) in a confined pig house (three pigs per pen) with six replicate pens per treatment. The growing diet was given for periods of 14±3 d and the finishing diet was given for periods of 28±3 d. The fat type had no significant effect either on growth performance or on chemical composition or on meat quality in growing-finishing pigs. Dietary fat type affected fatty acid composition, with higher levels of unsaturated fatty acids (UFAs) and monounsaturated fatty acids (MUFAs) in the olive oil group. Microarray analysis in the Longissimus dorsi identified 6 genes, related to insulin signaling pathway, that were differentially expressed among the different feed groups. Real time-PCR was conducted on the six genes in the longissimus dorsi muscle (LM). In particular, the genes encoding the protein kinase, cAMP-dependent, regulatory, type II, alpha (PRKAR2A) and the catalytic subunit of protein phosphatase 1, beta isoform (PPP1CB) showed the highest expression level in the olive oil group (respectively, p<0.05, p<0.001). The results of this study indicate that the type of dietary fat affects fatty acid composition and insulin signaling-related gene expression in the LM of pigs.

The Effect of Plant Extracts on In-vitro Ruminal Fermentation, Methanogenesis and Methane-related Microbes in the Rumen

The effect on methanogens attached to the surface of rumen ciliate protozoa by the addition of plant extracts (pine needles and ginkgo leaves) was studied with particular reference to their effectiveness for decreasing methane emission. The plant extracts (pine needles and ginkgo leaves) were added to an in vitro fermentation incubated with rumen fluid. The microbial population including bacteria, ciliated-associated methanogen, four different groups of methanogens and Fibrobacter succinogenes were quantified by using the real-time PCR. Gas profiles including methane, carbon dioxide and hydrogen, and runinal fermentation characteristics were observed in vitro. The methane emission from samples with an addition of individual juices from pine needles, ginkgo leaves and 70% ethanol extract from ginko leaves was significantly lower (p<0.05, 27.1, 28.1 and 28.1 vs 34.0 ml/g DM) than that of the control, respectively. Total VFAs in samples with an addition of any of the plant extracts were significantly lower than that of the control (p<0.05) as well. The order Methanococcales and the order Methanosarcinales were not detected by using PCR in any incubated mixtures. The ciliate-associated methanogens population decreased from 25% to 49% in the plant extacts as compared to control. We speculate that the supplementation of juice from pine needles and ginkgo leaves extract (70% ethanol extract) decreased the protozoa population resulting in a reduction of methane emission in the rumen and thus inhibiting methanogenesis. The order Methanobacteriales community was affected by addition of all plant extracts and decreased to less than the control, while the order Methanomicrobiales population showed an increase to more than that of the control. The F. succinogenes, the major fibrolytic microorganism, population in all added plant extracts was increased to greater than that of the control. In conclusion, pine needles and ginkgo leaves extracts appear to have properties that decrease methanogenesis by inhibiting protozoa species and may have a potential for use as additives for ruminants.

Glioma: Application of histogram analysis of pharmacokinetic parameters from T1-weighted dynamic contrast-enhanced MR imaging to tumor grading

BACKGROUND AND PURPOSE

The usefulness of pharmacokinetic parameters for glioma grading has been reported based on the perfusion data from parts of entire-tumor volumes. However, the perfusion values may not reflect the entire-tumor characteristics. Our aim was to investigate the feasibility of glioma grading by using histogram analyses of pharmacokinetic parameters including the volume transfer constant, extravascular extracellular space volume per unit volume of tissue, and blood plasma volume per unit volume of tissue from T1-weighted dynamic contrast-enhanced perfusion MR imaging.

MATERIALS AND METHODS

Twenty-eight patients (14 men, 14 women; mean age, 49.75 years; age range, 25-72 years) with histopathologically confirmed gliomas (World Health Organization grade II, n = 7; grade III, n = 8; grade IV, n = 13) were examined before surgery or biopsy with conventional MR imaging and T1-weighted dynamic contrast-enhanced perfusion MR imaging at 3T. Volume transfer constant, extravascular extracellular space volume per unit volume of tissue, and blood plasma volume per unit volume of tissue were calculated from the entire-tumor volume. Histogram analyses from these parameters were correlated with glioma grades. The parameters with the best percentile from cumulative histograms were identified by analysis of the area under the curve of the receiver operating characteristic analysis and were compared by using multivariable stepwise logistic regression analysis for distinguishing high- from low-grade gliomas.

RESULTS

All parametric values increased with increasing glioma grade. There were significant differences among the 3 grades in all parameters (P < .01). For the differentiation of high- and low-grade gliomas, the highest area under the curve values were found at the 98th percentile of the volume transfer constant (area under the curve, 0.912; cutoff value, 0.277), the 90th percentile of extravascular extracellular space volume per unit volume of tissue (area under the curve, 0.939; cutoff value, 19.70), and the 84th percentile of blood plasma volume per unit volume of tissue (area under the curve, 0.769; cutoff value, 11.71). The 98th percentile volume transfer constant value was the only variable that could be used to independently differentiate high- and low-grade gliomas in multivariable stepwise logistic regression analysis.

CONCLUSIONS

Histogram analysis of pharmacokinetic parameters from whole-tumor volume data can be a useful method for glioma grading. The 98th percentile value of the volume transfer constant was the most significant measure.

Optical properties of Dirac electrons in a parabolic well

A single electron transitor may be fabricated using qunatum dots. A good model for the confinement potential of a quantum dot is a parabolic well. Here we consider such a parabolic dot made of graphene. Recently, we found counter intuitively that resonant quasi-boundstates of both positive and negative energies exist in the energy spectrum. The presence of resonant quasi-boundstates of negative energies is a unique property of massless Dirac fermions. As magnetic field B gets smaller the energy width of these states become broader and for sufficiently weak value of B resonant quasi-bound states disappear into a quasi-continuum. In the limit of small B resonant and nonresonant states transform into discrete anomalous states with a narrow probability density peak inside the well and another broad peak under the potential barrier. In this paper we compute the optical strength between resonant quasi-bound states as a function of B, and investigate how the signature of resonant quasi-bound states of Dirac electrons may appear in optical measurements.

Resonant, non-resonant and anomalous states of Dirac electrons in a parabolic well in the presence of magnetic fields

We report on several new basic properties of a parabolic dot in the presence of a magnetic field. The ratio between the potential strength and the Landau level (LL) energy spacing serves as the coupling constant of this problem. In the weak coupling limit the energy spectrum in each Hilbert subspace of an angular momentum consists of discrete LLs of graphene. In the intermediate coupling regime non-resonant states form a closely spaced energy spectrum. We find, counter-intuitively, that resonant quasi-bound states of both positive and negative energies exist in the spectrum. The presence of resonant quasi-bound states of negative energies is a unique property of massless Dirac fermions. As the strong coupling limit is approached resonant and non-resonant states transform into anomalous states, whose probability densities develop a narrow peak inside the well and another broad peak under the potential barrier. These properties may investigated experimentally by measuring optical transition energies that can be described by a scaling function of the coupling constant.

Effects of feeding crude glycerin on performance and ruminal kinetics of lactating Holstein cows fed corn silage- or cottonseed hull-based, low-fiber diets

The objective was to determine whether crude glycerin could partially replace concentrate ingredients in corn silage- or cottonseed hull-based diets formulated to support minimal milk fat production without reducing milk production. Multiparous, lactating Holstein cows (n=24; 116 ± 13d in milk) were assigned to dietary treatments arranged in a 2 × 3 factorial design; namely, 2 dietary roughage sources (cottonseed hulls or corn silage) and 3 dietary concentrations of glycerin [0, 5, or 10% on a dry matter (DM) basis]. Four different cows received each dietary treatment in each of 3 periods such that each diet was evaluated using 12 cows. Crude glycerin, produced using soybean oil, contained 12% water, 5% oil, 6.8% sodium chloride, and 0.4% methanol. Glycerin partially replaced ground corn, corn gluten feed, and citrus pulp. Diets of minimum fiber concentrations were fed to lactating dairy cows and resulted in low concentrations of milk fat (averaging 3.12% for cows fed diets without glycerin). The effects of glycerin on cow performance and ruminal measurements were the same for both dietary roughage sources with the exception of feed efficiency. Replacing concentrate with crude glycerin at 5% of dietary DM increased DM intake without increasing milk yield. Concentration and yield of milk fat were reduced when glycerin was fed at 10% of dietary DM. This was accompanied by a 30% reduction in apparent total-tract digestion of dietary neutral detergent fiber. Crude glycerin affected the microbial population in the rumen as evidenced by increased molar proportions of propionic, butyric, and valeric acids and decreased molar proportions of acetic acid. Efficiency of N utilization was improved as evidenced by lower concentrations of blood urea nitrogen and ruminal ammonia-N. Cows fed cottonseed hull-based diets consumed 5.3 kg/d more DM but produced only 1.7 kg/d more milk, resulting in reduced efficiency. Increased production of ruminal microbial protein, molar proportion of propionic acid, and passage of ruminal fluid resulted from feeding the cottonseed hull- versus corn silage-based diets, although apparent digestibilities of DM and neutral detergent fiber were reduced. Replacing 5 and 10% of concentrate ingredients with crude glycerin improved efficiency of 4% fat-corrected milk production when corn silage-based diets were fed but decreased it when cottonseed hull-based diets were fed.

Combined Bacillus licheniformis and Bacillus subtilis infection in a patient with oesophageal perforation

Species of the genus Bacillus are a common laboratory contaminant, therefore, isolation of these organisms from blood cultures does not always indicate infection. In fact, except for Bacillus anthracis and Bacillus cereus, most species of the genus Bacillus are not considered human pathogens, especially in immunocompetent individuals. Here, we report an unusual presentation of bacteraemia and mediastinitis due to co-infection with Bacillus subtilis and Bacillus licheniformis, which were identified by 16S RNA gene sequencing, in a patient with an oesophageal perforation.

Can a repulsive potential in graphene have boundstates in a magnetic field?

We consider Klein tunneling through a repulsive and cylindrical potential with range R and strength V. Recently it was found that, in the strong coupling regime R/l < 1, the repulsive potential can have bound states peaked inside the potential with tails extending over l mean square root of 2(N+1), where N is Landau level (LL) index and f is the magnetic length. The presence of these bound states is a consequence of a subtle interplay between Klein tunneling and quantization effect of magnetic fields. Because of the presence of these bound states the effective coupling between the repulsive potential and an electron can be attractive. Here we show that this effect is a consequence of singular interaction between the repulsive potential and an electron that cannot be captured in perturbative approaches.

Electrical characteristic analysis using low-frequency noise in low-temperature polysilicon thin film transistors

This study carried out an electrical characteristic analysis using low-frequency noise (LFN) in top gate p-type low-temperature polysilicon thin film transistors (LTPS TFTs) with different active layer thicknesses between 40 nm and 80 nm. The transfer characteristic curves show that the 40-nm device has better electrical characteristics compared with the 80-nm device. The carrier number fluctuation, with and without correlated mobility fluctuation model in both devices, has modeled well the measured noise. On the other hand, the trap density and coulomb scattering in the 40-nm device are smaller compared with the 80-nm device. To confirm the effectiveness of the LFN noise analysis, the trap densities at a grain boundary are extracted using in both devices the similar methods of Proano et al. and Levinson et al. That is, coulomb scattering, caused by the trapped charges at or near the interface, has a greater effect on the device with inferior electrical properties. Based on the LFN and the quantitative analysis of the trap density at a grain boundary, the interface traps between the active layer and the gate insulator can explain the devices' electrical degradation.

Stay-green ranking and maturity of corn hybrids: 1. Effects on dry matter yield, nutritional value, fermentation characteristics, and aerobic stability of silage hybrids in Florida

This study determined effects of maturity, stay-green (SG) ranking, and hybrid source on dry matter (DM) yield, nutritive value, fermentation, and aerobic stability of corn hybrids. One high stay-green (HSG) hybrid and one average stay-green (ASG) hybrid with similar relative maturity (117 d) from each of 2 seed companies (Croplan Genetics, St. Paul, MN; Pioneer Hi-Bred International, Des Moines, IA) were grown on 1-× 6-m plots at random locations within each of 4 blocks. The hybrids were harvested at 25, 32, and 37% DM from each plot and separated into thirds for botanical fractionation and analysis, whole-plant chemical analysis, and ensiling. Chopped, whole plants were ensiled (8 kg) in quadruplicate in 20-L mini-silos for 107 d. A split-plot design was used for the study. Yields of whole-plant and digestible DM and concentrations of starch and DM increased with maturity, whereas concentrations of crude protein, water-soluble carbohydrates, and neutral detergent fiber decreased. High SG hybrids had greater DM yield than ASG hybrids when harvested at 25 and 37%, but not 32% DM. Unlike those from Croplan Genetics, the Pioneer HSG hybrid had greater ear and whole-plant DM concentration than their ASG hybrids. Stover moisture and CP concentration were greater among HSG versus ASG hybrids, particularly among Croplan Genetics hybrids. Croplan Genetics HSG hybrids had greater neutral and acid detergent fiber concentrations and lower in vitro DM digestibility in the unensiled whole-plant, the stover, and the silage than their ASG hybrids, whereas contrasting trends were evident for Pioneer hybrids. Silage fermentation indices were largely unaffected by hybrid SG ranking, maturity, or source. Yeast counts increased with maturity and exceeded 10(5) cfu/g; therefore, all silages deteriorated with 26 h, irrespective of treatment. Among the hybrids examined, the optimal maturity for optimizing DM yield and nutritive value of the ASG and HSG hybrids was 37% DM. Stay-green ranking had maturity-dependent effects on the yield of hybrids but had varying effects on nutritional value depending on the source of the hybrid.

Confinement and deconfinement in the potential of antidot arrays of a massless Dirac electron in magnetic fields

We have investigated the effect of inter-Landau level mixing on confinement/deconfinement in antidot potentials of states with energies less than the potential height of the antidot array. We find that, depending on the ratio between the size of the antidot R and the magnetic length [Formula: see text], probability densities display confinement or deconfinement in antidot potentials (B is the magnetic field). When R/ℓ < 1 inter-Landau level mixing is strong and probability densities with energy less than the potential height are non-chiral and localized inside antidot potentials. However, in the strong magnetic field limit R/ℓ ≫ 1, where inter-Landau level mixing is small, they are delocalized outside antidot potentials, and are chiral for N = 0 Landau level (LL) states while non-chiral for N = 1. In the non-trivial crossover regime R/ℓ ∼ 1 localized and delocalized probability densities coexist. States that are delocalized outside antidots when R/ℓ > 1 form a nearly degenerate band and their probability densities are independent of k, in contrast to the case of R/ℓ < 1.

New limits on interactions between weakly interacting massive particles and nucleons obtained with CsI(Tl) crystal detectors

New limits are presented on the cross section for weakly interacting massive particle (WIMP) nucleon scattering in the KIMS CsI(Tℓ) detector array at the Yangyang Underground Laboratory. The exposure used for these results is 24 524.3  kg·days. Nuclei recoiling from WIMP interactions are identified by a pulse shape discrimination method. A low energy background due to alpha emitters on the crystal surfaces is identified and taken into account in the analysis. The detected numbers of nuclear recoils are consistent with zero and 90% confidence level upper limits on the WIMP interaction rates are set for electron equivalent energies from 3 to 11 keV. The 90% upper limit of the nuclear recoil event rate for 3.6-5.8 keV corresponding to 2-4 keV in NaI(Tℓ) is 0.0098 counts/kg/keV/day, which is below the annual modulation amplitude reported by DAMA. This is incompatible with interpretations that enhance the modulation amplitude such as inelastic dark matter models. We establish the most stringent cross section limits on spin-dependent WIMP-proton elastic scattering for the WIMP masses greater than 20  GeV/c2.

Adhesion and growth of human umbilical vein endothelial cells on collagen-treated PU/PEGDA IPNs

For ideal non-thrombogenicity under normal physiologic conditions, we propose endothelialization. Endothelialization means that synthetic biomaterials are seeded by endothelial cells to mimic natural blood vessels. In our study, we synthesized amphiphilic polyurethane (PU)/poly(ethyleneglycol)diacrylate (PEGDA) interpenetrating polymer networks (IPNs) with different levels of surface energy to investigate the effect of adhesion and the growth of human umbilical vein endothelial cells (HUVECs). Collagen with cell-binding molecules was adsorbed on the surface of PU/PEGDA IPNs to enhance the adhesion of HUVECs. The morphology of collagens adsorbed on the IPN surfaces depends highly on the surface energy of the IPNs. As the surface becomes hydrophilic, there is greater aggregation of the adsorbed collagens on the IPN surface. The HUVECs successfully adhere to the collagen-immobilized IPN surface. The morphology of the endothelial cells (ECs) that adhere to IPN 2k-C and IPN 2k after 1 day and after 3 days incubation shows that ECs were successfully spread. The adhesion and the proliferation of ECs increase on non-treated IPN surfaces as the hydrophobicity of the IPNs increases. The surface energy of IPN 2k-C is suitable for the adhesion and proliferation of ECs. Therefore, platelet adhesion is significantly reduced on the EC-hybridized surface of IPNs.

Effect of applying bacterial inoculants containing different types of bacteria to corn silage on the performance of dairy cattle

This study examined the effect of applying different bacterial inoculants to corn silage at the time of ensiling on the performance of lactating dairy cows. Corn plants were harvested at 35% dry matter (DM), chopped, and ensiled in 2.4-m-wide bags after application of (1) no inoculant (CON); (2) Biotal Plus II (B2) containing Pediococcus pentosaceus and Propionibacteria freudenreichii; (3) Buchneri 40788 (BUC) containing Lactobacillus buchneri; or (4) Buchneri 500 (B500) containing Pediococcus pentosaceus and L. buchneri. All inoculants were supplied by Lallemand Animal Nutrition (Milwaukee, WI). Each of the 4 silages was included in separate total mixed rations consisting of 44% corn silage, 50% concentrate, and 6% alfalfa hay (DM basis). Fifty-two lactating Holstein cows were stratified according to milk production and parity and randomly assigned at 22 d in milk to the 4 dietary treatments. Cows were fed for ad libitum consumption and milked twice daily for 49 d. Dietary treatment did not affect intakes (kg/d) of DM (20.0), crude protein (CP; 3.7), neutral detergent fiber (NDF; 5.7), or acid detergent fiber (ADF; 3.6), or digestibility (%) of DM (73.9) or CP (72.4). However, NDF digestibility was lower in cows fed B2 compared with those fed other diets (45.3 vs. 53.0%). Consequently, cows fed B2 had lower digestible NDF intake (kg/d) than those fed other diets (2.5 vs. 3.0 kg/d). Dietary treatment did not affect milk yield (32.3 kg/d), efficiency of milk production (1.61), concentrations of milk fat (3.18%) and protein (2.79%), or yields of milk fat (1.03 kg/d) and protein (1.26 kg/d). Inoculant application to corn silage did not affect milk yield or feed intake of cows.

A prospective longitudinal study evaluating the usefulness of a T-cell-based assay for latent tuberculosis infection in kidney transplant recipients

We evaluated whether ELISPOT assay can predict tuberculosis (TB) development in kidney-transplantation (KT) recipients with a negative tuberculin skin test (TST). All adult patients admitted to a KT institute between June 2008 and December 2009 were enrolled; TB development after KT was observed between June 2008 and December 2010. Isoniazid (INH) was given to those patients with positive TST or clinical risk factors for latent TB infection (LTBI). ELISPOT assay was performed on all patients, and TB development after KT was observed by a researcher blinded to the results of ELISPOT. A total of 312 KT recipients including 242 (78%) living-donor KT were enrolled. Of the 312 patients, 40 (13%) had positive TST or clinical risk factors for LTBI and received INH; none developed TB after KT. Of the remaining 272 patients, 4 (6%) of 71 with positive ELISPOT assay developed TB after KT, whereas none of the 201 patients with negative (n = 171) or indeterminate ELISPOTs (n = 30) developed TB after KT (rate difference between positive and negative/indeterminate ELISPOT, 3.3 per 100 person-years [95% CI 1.4-5.1, p<0.001]). Positive ELISPOT results predict subsequent development of TB in KT recipients in whom LTBI cannot be detected by TST or who lack clinical risk factors for LTBI.

Calpain cleaved-55kDa N-terminal huntingtin delocalizes from neurons to astrocytes after ischemic injury

The huntingtin (htt) mutation causes a polyglutamine expansion in the N-terminal region of protein. Mutant N-htt proteolytic fragments aggregate and cause cell death in Huntington's disease (HD). The normal huntingtin also can be cleaved by calpain and produce N-terminal htt fragments following ischemic injury, but the fate of cleaved fragment in dead neurons in the brain are unclear. To determine the localization of huntingtin following proteolysis, we examined htt expression after transient ischemic injury. Huntingtin immunoreactivity in mixed cultures of neuronal and astrocytes-derived clonal cells showed alteration of immunoreactivity from neurons into astrocytes. In the brain, both focal and global ischemia induced reactive astrocytes that were co-immunoreactive for huntingtin with elevated GFAP expression. The immunoreactive huntingtin was 55kDa calpain-cleaved N-terminal fragment, which appeared initially in the process, and extended into the cytoplasm of astrocytes. The results showed, after ischemic injury, huntingtin accumulated in astrocytes indicating that astrocytes may play a role in uptake of cleaved N-htt fragments.

Vitamin or antioxidant intake (or serum level) and risk of cervical neoplasm: a meta-analysis

BACKGROUND

Case-control studies have reported the preventive effect of vitamin or antioxidant intake on cervical neoplasms such as cervical intraepithelial neoplasia (CIN) and invasive cervical cancer. However, the findings are inconsistent.

OBJECTIVE

To investigate quantitative effects of vitamin or antioxidant intake on cervical neoplasm using meta-analysis.

SEARCH STRATEGY

We searched PubMed, EMBASE and the Cochrane Library in November 2008. All articles searched were independently reviewed and selected by two evaluators according to predetermined selection criteria.

SELECTION CRITERIA

We included case-control studies reporting an association between vitamin or antioxidant intake (or serum level) and cervical neoplasm risk and reporting the adjusted odds ratios (OR) and 95% confidence intervals (CI), whenever possible.

DATA COLLECTION AND ANALYSIS

After retrieval of data from selected articles, we performed a meta-analysis using both fixed-effects and random- effects models.

MAIN RESULTS

Of 274 articles meeting our initial criteria, we included 22 case-control studies involving a total of 10,073 participants. In meta-analyses by type of vitamin or antioxidant, a significant preventive effect on cervical neoplasm was found in intakes of vitamin B12 (OR 0.35, 95% CI 0.19-0.63; n=2), vitamin C (OR 0.67, 95% CI 0.55-0.82; n=8), vitamin E (OR 0.56, 95% CI 0.35-0.88; n=10), and beta-carotene (OR 0.68, 95% CI 0.55-0.84; n=9).

AUTHORS' CONCLUSIONS

The findings of this meta-analysis indicate that overall, there were preventive effects of vitamin or antioxidant intake on cervical neoplasms in case-control studies.

Dirac electrons of a split-gate Hall bar

In this work we study several unusual properties of Klein tunneling through the abrupt and flat barriers of a split-gate Hall bar system of graphene. We show that Klein tunneling of Dirac electrons can be rather strong in such a system, and that a significant electron density can be present under the barrier. It can be shown that the probability wavefunctions for large angular momenta are identical to the probability wavefunctions of the same angular momenta in the absence of the potential barrier, i.e., it is as if the barrier does not exist and the Klein tunneling is complete. This is a unique effect in a magnetic field. We propose that STM measurements may be used to detect the presence of such a density. We have also investigated drift velocity of electrons as the center of probability wavefunction varies from outside to inside of the flat potential barrier, and find a significant deviation from the semiclassical result.

Optimization of selective emitter fabrication method for solar cells using a laser grooving

In this paper, screen-printing laser grooved buried contact (LGBC) method was applied, which is compatible with the existing screen-printed solar cell equipment and facilities. Experiments were performed in order to optimize short circuit current (I(sc)), open circuit voltage (V(oc)) and fill factor of high efficiency solar cells. To enhance I(sc), V(oc) and efficiency, heavy doping was performed at low sheet resistance in the laser grooved region of the cell. In contrast, light doping was carried out at a high sheet resistance in the non-laser grooved region. To increase fill factor, porous silicon found on the wafer after dipping in an HF solution to remove SiN(x), was cleared. The fabricated screen-printing LGBC solar cell using a 125 mm x 125 mm single crystalline silicon wafer exhibited an efficiency of 17.2%. The results show that screen-printing LGBC method can be applied for high efficiency solar cells.

Effect of applying inoculants with heterolactic or homolactic and heterolactic bacteria on the fermentation and quality of corn silage

This study examined the effect of applying different bacterial inoculants on the fermentation and quality of corn silage. Corn plants were harvested at 35% DM, chopped, and ensiled in 20-L mini silos after application of (1) deionized water (CON) or inoculants containing (2) 1 × 10(5) cfu/g of Pediococcus pentosaceus 12455 and Propionibacteria freudenreichii (B2); (3) 4 × 10(5) cfu/g of Lactobacillus buchneri 40788 (BUC); or (4) 1 × 10(5) cfu/g of Pediococcus pentosaceus 12455 and 4 × 10(5) cfu/g of L. buchneri 40788 (B500). Four replicates of each treatment were weighed into polyethylene bags within 20-L mini silos. Silos were stored for 575 d at ambient temperature (25°C) in a covered barn. After silos were opened, aerobic stability, chemical composition, and yeast and mold counts were determined. The DNA in treated and untreated silages was extracted using lysozyme/sodium dodecyl sulfate lysis and phenol/chloroform and used as a template for a conventional PCR with primers designed on the 16S rRNA gene to detect the presence of L. buchneri in all silage samples. Acetic acid concentration was greater in B2 silages versus others (6.46 vs. 4.23% DM). Silages treated with BUC and B500 had lower pH and propionic acid concentration and greater lactic acid concentration than others. The B500 silage had the greatest lactic:acetic acid ratio (1.54 vs. 0.41), and only treatment with BUC reduced DM losses (5.0 vs. 14.3%). Yeast and mold counts were less than the threshold (10(5)) typically associated with silage spoilage and did not differ among treatments. Consequently, all silages were very stable (>250 h). Aerobic stability was not improved by any inoculant but was lower in B500 silages versus others (276 vs. 386 h). The conventional PCR confirmed the presence of similar populations of L. buchneri in all silages. This may have contributed to the prolonged aerobic stability of all silages.

Coding single-nucleotide polymorphisms of interleukin-1 gene cluster are not associated with Kawasaki disease in the Korean population

This study aimed to examine whether coding single-nucleotide polymorphisms (cSNPs) of the interleukin-1 gene cluster [interleukin-1-alpha (IL1α), IL1β, IL-1-receptor antagonist (IL1RN)] are genetic markers of susceptibility to Kawasaki disease (KD) in the Korean population. The study enrolled 109 KD patients and 287 healthy control subjects. Four cSNPs [rs17561 (Ala114Ser) of IL1α, rs1143634 (Phe105Phe) of IL1β, and rs419598 (Ala23Ala) and rs315952 (Ser96Ser) of IL1RN] were genotyped using the restriction fragment-length polymorphism (RFLP) and direct sequencing. The KD patients were divided into two groups according to the presence of coronary artery lesions (CALs). For genetic analysis, SNPStats, HapAnalyzer, Helixtree, and SNPAnalyzer were used. The allele and genotype frequencies of the IL1 gene cluster polymorphisms in the KD patients had a pattern similar to that in the control subjects. Furthermore, no association was observed between four cSNPs of the IL1 gene cluster and the development of CALs in KD. These results suggest that the IL1 gene cluster may not be associated with susceptibility to KD and the development of CALs in the Korean population.

Microarray Analysis of Gene Expression Profiles in Response to Treatment with Melatonin in Lipopolysaccharide Activated RAW 264.7 Cells

Melatonin, which is the main product of the pineal gland, has well documented antioxidant and immune-modulatory effects. Macrophages produce molecules that are known to play roles in inflammatory responses. We conducted microarray analysis to evaluate the global gene expression profiles in response to treatment with melatonin in lipopolysaccharide (LPS) activated RAW 264.7 macrophage cells. In addition, eight genes were subjected to real-time reverse transcription polymerase chain reaction (RT-PCR) to confirm the results of the microarray. The cells were treated with LPS or melatonin plus LPS for 24 hr. LPS induced the up-regulation of 1073 genes and the down-regulation of 1144 genes when compared to the control group. Melatonin pretreatment of LPS-stimulated RAW 264.7 cells resulted in the down regulation of 241 genes and up regulation of 164 genes. Interestingly, among genes related to macrophage-mediated immunity, LPS increased the expression of seven genes (Adora2b, Fcgr2b, Cish, Cxcl10, Clec4n, Il1a, and Il1b) and decreased the expression of one gene (Clec4a3). These changes in expression were attenuated by melatonin. Furthermore, the results of real-time PCR were similar to those of the microarray. Taken together, these results suggest that melatonin may have a suppressive effect on LPS-induced expression of genes involved in the regulation of immunity and defense in RAW 264.7 macrophage cells. Moreover, these results may explain beneficial effects of melatonin in the treatment of various inflammatory conditions.