[EDA mutation screening and phenotype analysis in patients with tooth agenesis]

OBJECTIVE

To screen the ectodysplasin A (EDA) gene mutation in the patients with non-syndromic tooth agenesis and ectodermal dysplasia, and to analyze the phenotype of missing teeth pattern in these two groups of patients.

METHODS

In the study, 174 patients with tooth agenesis (143: non-syndromic, 31: ectodermal dysplasia) and 451 health control volunteers were enrolled from the clinic, and the genome DNA was extracted from either peripheral blood or oral mucosal swab. The coding region of EDA gene was then amplified by PCR, sequenced and blasted to online NCBI database. The missing teeth were recorded for all patients, and the missing teeth from patients with EDA mutation were compared among the different dentition sites.

RESULTS

33 patients were identified with EDA mutation. In the non-syndromic patients, 13/143(9.09%) were identified with EDA mutation, while in patients with ectodermal dysplasia, 20/31(64.52%) were found with EDA mutation. Ten novel EDA mutations were identified (c.769G>C[p.G257R ],c.936C>G[p.I312M],c.223G>A[p.E75K], .1166C>T[p.P389L],c.133G>C[p.G45R],c.1109G>A[p.E370K],c.914G>T[p.S305I], c.916C>T[p.Q306X],c.602G>T[p.G201V],c.88-89insG[p.A30GfsX69]). For each dentition site there was no statistic difference in the number of missing teeth between the left and right sides, so the number from both sides were combined later in the analysis. In the patients with EDA mutation, the non-syndromic patients had fewer missing teeth (15.9±6.4 missing teeth for each, 207/364 in total) than the patients with ectodermal dysplasia (23.9±4.3, 478/560). In the non-syndromic patients with EDA mutation, the maxillay central incisors and first molars were less affected, with the same missing rate as 19.2% (5/26). While the mandibular central incisors (with a missing rate of 76.9%, 20/26), the maxillary lateral incisors (the missing rate: 88.5%, 23/26), the mandibular lateral incisors (the missing rate: 80.8%, 21/26), and the maxillary first premolars (the missing rate: 80.8%, 21/26) were more likely to be missing. In the ectodermal dysplasia patients with EDA mutation, only maxillary central incisors (the missing rate: 60%, 24/40), maxillary canines (the missing rate: 70%, 28/40), mandibular canines (the missing rate: 67.5%, 27/40), maxillary first molars (the missing rate: 65%, 26/40) and mandibular first molars (the missing rate: 72.5%, 29/40) had higher possibility of persistence. Teeth at other dentition sites were more likely to be affected (the minimum missing rate: 87.5%, 35/40).

CONCLUSION

The findings would help to reveal the EDA gene and its function in ectodermal organogenesis.

[Influence of implant restoration on traditional restoration idea]

Implant restoration affected the traditional restoration idea. Artificial implant restoration has a profound influence on the design of dental restoration. Implant supported prostheses have not only changed the method of oral rehabilitation, but also integrated revolutionary concept with the traditional treatment protocol. By using implants, posterior missing molars can be effectively restored and thus eliminating the disadvantages of traditional removable partial denture for Kennedy classification Ⅰ, Ⅱ partically edentulous dentition. Full edentulous arch can also be restored with implant fixed denture which provide much better oral health related quality of life compared with the traditional complete denture. It is useful to master the theory and skills of artificial implant restoration, and to provide a reference for the restoration of oral physiological function.

Applying the Back-Propagation Neural Network model and fuzzy classification to evaluate the trophic status of a reservoir system

The trophic state index, and in particular, the Carlson Trophic State Index (CTSI), is critical for evaluating reservoir water quality. Despite its common use in evaluating static water quality, the reliability of the CTSI may decrease when water turbidity is high. Therefore, this study examines the reliability of the CTSI and uses the Back-Propagation Neural Network (BPNN) model to create a new trophic state index. Fuzzy theory, rather than binary logic, is implemented to classify the trophic status into its three grades. The results show that compared to the CTSI with traditional classification, the new index with fuzzy classification can improve trophic status evaluation with high water turbidity. A reliable trophic state index can correctly describe reservoir water quality and allow relevant agencies to address proper water quality management strategies for a reservoir system.

Effects of environmental temperature and dietary manganese on egg production performance, egg quality, and some plasma biochemical traits of broiler breeders

An experiment was conducted to investigate the effects of environmental temperature and dietary Mn on egg production performance, egg quality, and some plasma biochemical traits of broiler breeders. A completely randomized factorial design involved 2 environmental temperatures (a normal temperature, 21 ± 1°C, and a high temperature, 32 ± 1°C) × 3 dietary Mn treatments (a Mn-unsupplemented corn–soybean meal basal diet or the basal diet supplemented with 120 mg of Mn/kg of diet as either MnSO4·H2O or manganese proteinate). There were 6 treatments with 6 replicates (4 birds per replicate). High temperature decreased egg weight (P < 0.0001), laying rate (P < 0.0001), egg yield (P < 0.0001), feed intake (P < 0.0001), egg:feed ratio (P < 0.0001), eggshell strength (P < 0.05) and thickness (P < 0.0001), plasma triiodothyronine level (P < 0.05), and alkaline phosphatase activity (P < 0.04) whereas it increased rectal temperature (P < 0.0001); plasma malondialdehyde level (P < 0.02); and activities (P < 0.002) of lactic dehydrogenase, aspartate aminotransferase, and creatine kinase. Broiler breeders fed the diets supplemented with Mn regardless of source had greater (P < 0.05) eggshell strength and lower (P ≤ 0.05) plasma triiodothyronine level and protein carbonyl content than those fed the control diet. The broiler breeders fed the diet supplemented with the organic Mn had greater (P < 0.01) eggshell thickness than those fed the control diet. There were interactions (P < 0.05) between environmental temperature and dietary Mn in laying rate, egg yield, feed intake, and egg:feed ratio. Under normal temperature, dietary Mn did not affect the above 4 parameters; however, under high temperature, broiler breeders fed the diet supplemented with the organic Mn showed greater (P < 0.03) improvements in these 4 parameters than those fed the control diet. The results from this study indicated that high temperature significantly impaired egg production performance and eggshell quality and induced lipid peroxidation and tissue damage whereas dietary supplementation of either organic or inorganic Mn improved eggshell strength and thermotolerance and reduced protein oxidation and that the organic Mn could alleviate the negative effect of high temperature on egg production performance of broiler breeders at the period of 32 to 45 wk of age.

Selection for Duration of Fertility and Mule Duck White Plumage Colour in a Synthetic Strain of Ducks (Anas platyrhynchos)

A synthetic strain of ducks (Anas platyrhynchos) was developed by introducing genes for long duration of fertility to be used as mother of mule ducklings and a seven-generation selection experiment was conducted to increase the number of fertile eggs after a single artificial insemination (AI) with pooled Muscovy semen. Reciprocal crossbreeding between Brown Tsaiya LRI-2 (with long duration of fertility) and Pekin L-201 (with white plumage mule ducklings) ducks produced the G0. Then G1 were intercrossed to produce G2 and so on for the following generations. Each female duck was inseminated 3 times, at 26, 29, and 32 weeks of age. The eggs were collected for 14 days from day 2 after AI. Individual data regarding the number of incubated eggs (Ie), the number of fertile eggs at candling at day 7 of incubation (F), the total number of dead embryos (M), the maximum duration of fertility (Dm) and the number of hatched mule ducklings (H) with plumage colour were recorded. The selection criterion was the breeding values of the best linear unbiased prediction animal model for F. The results show high percentage of exhibited heterosis in G2 for traits to improve (19.1% for F and 12.9% for H); F with a value of 5.92 (vs 3.74 in the Pekin L-201) was improved in the G2. Heritabilities were found to be low for Ie (h (2) = 0.07±0.03) and M (h (2) = 0.07±0.01), moderately low for Dm (h (2) = 0.13±0.02), of medium values for H (h (2) = 0.20±0.03) and F (h (2) = 0.23±0.03). High and favourable genetic correlations existed between F and Dm (rg = 0.93), between F and H (rg = 0.97) and between Dm and H (rg = 0.90). The selection experiment showed a positive trend for phenotypic values of F (6.38 fertile eggs in G10 of synthetic strain vs 5.59 eggs in G4, and 3.74 eggs in Pekin L-201), with correlated response for increasing H (5.73 ducklings in G10 vs 4.86 in G4, and 3.09 ducklings in Pekin L-201) and maximum duration of the fertile period without increasing the embryo mortality rate. The average predicted genetic response for F was 40% of genetic standard deviation per generation of selection. The mule ducklings' feather colour also was improved. It was concluded that this study provided results for a better understanding of the genetics of the duration of fertility traits in the common female duck bred for mule and that the selection of a synthetic strain was effective method of improvement.

Determination of thin hydrodynamic lubricating film thickness using dichromatic interferometry

This paper introduces the application of dichromatic interferometry for the study of hydrodynamic lubrication. In conventional methods, two beams with different colors are projected consecutively on a static object. By contrast, the current method deals with hydrodynamic lubricated contacts under running conditions and two lasers with different colors are projected simultaneously to form interference images. Dichromatic interferometry incorporates the advantages of monochromatic and chromatic interferometry, which are widely used in lubrication research. This new approach was evaluated statically and dynamically by measuring the inclination of static wedge films and the thickness of the hydrodynamic lubricating film under running conditions, respectively. Results show that dichromatic interferometry can facilitate real-time determination of lubricating film thickness and is well suited for the study of transient or dynamic lubricating problems.

Asp68His mutation in the A1 domain of human factor V causes impaired secretion and ineffective translocation

Congenital factor V (FV) deficiency is a rare inherited disorder. We determined the mechanism of a missense mutation, Asp68His, in the A1 domain of the FV protein, is associated with severe FV deficiency. We characterized the mutant FV-Asp68His protein using in vitro expression studies by using specific secretion and degradation pathway inhibitors and analysed the intracellular translocation of the mutant protein by immunofluorescence staining. The Asp68His mutation caused very low levels of FV protein in the conditioned media, with normal specific FV activity. Similar mRNA degradation rates between FV-wild-type (wt) and FV-Asp68His mRNA showed that the Asp68His mutation does not affect FV expression at the transcriptional level. A specific secretion pathway inhibitor, brefeldin A, was used to demonstrate that the lower efficiency of transport to the outside of the cell for FV-Asp68His mutant protein compared with that of the FV-wt protein. Furthermore, we showed that the Asp68His mutation resulted in increased intracellular degradation through a MG132-mediated proteasomal degradation pathway. In the transfected cell lysates, FV-wt protein had multiple posttranslational modified forms, but the FV-Asp68His protein was not completely glycosylated. We further observed that the FV-Asp68His protein was retrieved in the endoplasmic reticulum only and did not undergo transport to the Golgi apparatus, leading to impaired secretion. These results strongly suggest that the Asp68His mutation may result in intracellular defective trafficking and enhanced degradation, and impaired secretion of FV protein.

Association between rs11001553 of DKK1 and non-syndromic tooth agenesis in the Chinese Han population

Tooth agenesis is one of the most common anomalies of human dentition. Recent genetic studies have provided information regarding a number of genes related to both syndromic and non-syndromic forms of hypodontia. In a previous study, we found that polymorphism in rs11001553 of DKK1 was associated with hypodontia in the Chinese Han population. In this study, we extended this investigation to 89 individuals diagnosed with sporadic non-syndromic oligodontia (40 males and 49 females). These individuals were analyzed with 268 subjects (123 males and 145 females) diagnosed with non-syndromic hypodontia and 190 healthy control subjects (99 males and 91 females). DNA was obtained from whole blood or saliva samples and genotyping was performed by matrix-assisted laser desorption ionization-time of flight mass spectrometry. Significant differences were observed in the allele and genotype frequencies of rs11001553 of DKK1. These data demonstrated an association between rs11001553 of DKK1, a tooth development-associated gene, and non-syndromic tooth agenesis in Chinese Han individuals. This information may provide further understanding of the molecular mechanisms of tooth agenesis. Furthermore, DKK1 can be regarded as a marker gene for the risk of tooth agenesis.

Pharmacokinetics of niacin, simvastatin and their metabolites in healthy Chinese subjects after single and multiple doses of a fixed dose combination tablet of niacin extended release/simvastatin

OBJECTIVE

A fixed dose combination tablet of niacin extended release (ER)/simvastatin was recently developed in China. This study was designed to assess and compare the pharmacokinetics of niacin, simvastatin and their metabolites in healthy Chinese subjects after single and multiple doses administration.

METHODS

From day 1 to day 7, 12 Chinese subjects were given a tablet every day at approximately 10 p.m. Serial blood samples were collected. Niacin and nicotinuric acid (NUA) in plasma, niacin, NUA, N-methylnicotinamide (MNA) and N-methyl-2-pyridone-5-carboxamide (2PY) in urine, simvastatin and simvastatin acid in plasma were determined by LC/MS/MS methods. Pharmacokinetic parameters on days 1 and 7 were compared.

RESULTS

The main pharmacokinetic parameters for the single and multiple doses were as -follows: Niacin: Tmax were 3.8±1.5 h and 3.9±2.0 h; Cmax were 2 091±1 315 ng/ml and 2 323±1 542 ng/ml; AUC0-t were 4 123.88±3 138.48 ng ∙ h/ml and 4 385.98±3 127.05 ng ∙ h/ml. NUA: Tmax were 4.7±1.7 h and 3.8±1.5 h; Cmax were 1 057±549 ng/ml and 1 087±470 ng/ml; AUC0-t were 4 012.49±2 168.68 ng ∙ h/ml and 4 040.45±1 886.57 ng ∙ h/ml. Simvastatin: Tmax were 1.8±1.0 h and 2.5±2.5 h; Cmax were 3.15±1.67 ng/ml and 4.87±4.11 ng/ml; AUC0-t were 9.03±5.10 ng ∙ h/ml and 17.63±13.93 ng ∙ h/ml. Simvastatin acid: Tmax were 5.8±1.7 h and 6.5±1.4 h; Cmax were 4.22±2.10 ng/ml and 9.30±8.09 ng/ml; AUC0-t were 34.65±16.89 ng ∙ h/ml and 61.62±46.41 ng ∙ h/ml. Urine Recovery rate of total niacin: (40.55±7.38)% and (62.87±12.04)%.

CONCLUSION

Compared with those after a single dose, pharmacokinetics of niacin and NUA was similar; total urine recovery of niacin was higher; exposure to simvastatin and simvastatin acid were higher following multiple doses.

QSAR studies on imidazopyrazine derivatives as Aurora A kinase inhibitors

Aurora kinases have emerged as attractive targets for the development of novel anti-cancer agents. A combined study of molecular docking, pharmacophore modelling and 3D-QSAR was performed on a series of imidazo [1, 2-a] pyrazines as novel Aurora kinase inhibitors to gain insights into the structural determinants and their structure-activity relationship. An ensemble of conformations based on molecular docking was used for PHASE pharmacophore studies. The developed best-fitted pharmacophore model was validated by diverse chemotypes of Aurora A kinase inhibitors and was consistent with the structural requirements for the docked binding mechanism. Subsequently, the pharmacophore-based alignment was used to develop PHASE and comparative molecular similarity indices analysis (CoMSIA) 3D-QSAR models. The best CoMSIA model showed good statistics (q (2 )= 0.567, r (2 )= 0.992), and the predictive ability of the model was validated using an external test set of 13 compounds giving a satisfactory prediction ([Formula: see text]). The 3D contour maps provided insight into the binding mechanism and highlighted key structural features that are essential to the inhibitory activity. Based on the PHASE and CoMSIA 3D-QSAR results, a set of novel Aurora A inhibitors were designed that showed excellent potencies.

Terahertz quantum cascade lasers operating up to ∼ 200 K with optimized oscillator strength and improved injection tunneling

A new temperature performance record of 199.5 K for terahertz quantum cascade lasers is achieved by optimizing the lasing transition oscillator strength of the resonant phonon based three-well design. The optimum oscillator strength of 0.58 was found to be larger than that of the previous record (0.41) by Kumar et al. [Appl. Phys. Lett. 94, 131105 (2009)]. The choice of tunneling barrier thicknesses was determined with a simplified density matrix model, which converged towards higher tunneling coupling strengths than previously explored and nearly perfect alignment of the states across the injection and extraction barriers at the design electric field. At 8 K, the device showed a threshold current density of 1 kA/cm2, with a peak output power of ∼ 38 mW, and lasing frequency blue-shifting from 2.6 THz to 2.85 THz with increasing bias. The wavelength blue-shifted to 3.22 THz closer to the maximum operating temperature of 199.5 K, which corresponds to ∼ 1.28ħω/κB. The voltage dependence of laser frequency is related to the Stark effect of two intersubband transitions and is compared with the simulated gain spectra obtained by a Monte Carlo approach.

Near-room-temperature mid-infrared quantum well photodetector

We demonstrate InGaAs mid-infrared quantum well infrared photodetectors (MIR PV-QWIPs) that enable cost-effective mature GaAs-based detection and imaging technologies, with exceptional material uniformity, reproducibility, and yield, over a large area, with high spectral selectivity, innate polarization sensitivity, radiation hardness, high detectivity, and high speed operation at TEC temperatures without bias.

Nontraumatic hemorrhagic stroke in young adults in taiwan

We reviewed the medical records and imaging studies on the in-hospital patients to investigate the clinical and etiological patterns in hemorrhagic stroke in young patients. We evaluated 210 patients (131 males and 79 females) aged 15-45 years who had traumatic hemorrhagic stroke between April 1, 1986, and November 30, 1992. Nontraumatic intracerebral hemorrhage was diagnosed in 170 patients (80.9%). The main causes of nontraumatic intracerebral hemorrhage were hypertension, ruptured arteriovenous malformation, and blood dyscrasia. A cause was not found in 42 patients (24.7%). Subarachnoid hemorrhage was found in 40 patients (19.1%). The main causes were ruptured aneurysms and arteriovenous malformations. The overall in-hospital survival of young patients with hemorrhagic stroke was 64.7%. Young adults with nontraumatic intracerebral and subarachnoid hemorrhage are a heterogeneous group. Hypertension accounts for about one-third of intracerebral hemorrhage and is an important preventable cause of hemorrhagic stroke in young adults in Taiwan.

Electrically switching transverse modes in high power THz quantum cascade lasers

The design and fabrication of a high power THz quantum cascade laser (QCL), with electrically controllable transverse mode is presented. The switching of the beam pattern results in dynamic beam switching using a symmetric side current injection scheme. The angular-resolved L-I curves measurements, near-field and far-field patterns and angular-resolved lasing spectra are presented. The measurement results confirm that the quasi-TM(01) transverse mode lases first and dominates the lasing operation at lower current injection, while the quasi-TM(00) mode lases at a higher threshold current density and becomes dominant at high current injection. The near-field and far-field measurements confirm that the lasing THz beam is maneuvered by 25 degrees in emission angle, when the current density changes from 1.9 kA/cm(2) to 2.3 kA/cm(2). A two-dimension (2D) current and mode calculation provides a simple model to explain the behavior of each mode under different bias conditions.

Mode-locked pulses from mid-infrared quantum cascade lasers

In this study, we report the unequivocal demonstration of midinfrared mode-locked pulses from quantum cascade lasers. The train of short pulses was generated by actively modulating the current and hence the gain of an edge-emitting quantum cascade laser (QCL). Pulses with duration of about 3 ps at full-width-at-half-maxima and energy of 0.5 pJ were characterized using a second-order interferometric autocorrelation technique based on a nonlinear quantum well infrared photodetector. The mode-locking dynamics in the QCLs was modeled based on the Maxwell-Bloch equations in an open two-level system. Our model reproduces the overall shape of the measured autocorrelation traces and predicts that the short pulses are accompanied by substantial wings as a result of strong spatial hole burning. The range of parameters where short mode-locked pulses can be formed is found.

Terahertz two-photon quantum well infrared photodetector

A two-photon detector based on intersubband transitions in GaAs/AlGaAs quantum wells operating in the Terahertz regime below the Reststrahlenband is reported. Resonantly enhanced optical nonlinearities enables sensitive quadratic detection at pJ pulse energies. We demonstrate its use in a quadratic autocorrelator for far-infrared picosecond pulses at around 7 THz.

Normal incidence detection of ultraviolet, visible, and mid-infrared radiation in a single GaAs/AlGaAs device

A GaAs/AlGaAs detector is demonstrated showing multiple detection capabilities. This detector exhibits a broad spectral response in the 200-870 nm (ultraviolet-visible) range for forward bias and in the 590-870 nm (visible) range for reverse bias. In the mid-IR region, two peaks at 5 and 8.9 microm can be observed for low and high forward bias voltages, respectively. In addition, the peak at 8.9 microm is sensitive to the polarization of the incoming radiation.

Quantum dots for terahertz generation

Nanostructures made of semiconductors, such as quantum wells and quantum dots (QD), are well known, and some have been incorporated in practical devices. Here we focus on novel structures made of QDs and related devices for terahertz (THz) generation. Their potential advantages, such as low threshold current density, high characteristic temperature, increased differential gain, etc, make QDs promising candidates for light emitting applications in the THz region. Our idea of using resonant tunneling through QDs is presented, and initial results on devices consisting of self-assembled InAs QDs in an undoped GaAs matrix, with a design incorporating a GaInNAs/GaAs short period superlattice, are discussed. Moreover, shallow impurities are also being explored for possible THz emission: the idea is based on the tunneling through bound states of individual donor or acceptor impurities in the quantum well. Initial results on devices having an AlGaAs/GaAs double-barrier resonant tunneling structure are discussed.

Two-photon photocurrent autocorrelation using intersubband transitions at nearly-resonant excitation

We investigate nonlinear mid-infrared detection via two-photon transitions involving two bound subbands and one continuum resonance in an n-type multiple quantum well. By varying the excitation energy, we have tuned the two-photon transition from resonant, yielding optimum resonant enhancement with a real intermediate state, to nearly-resonant, with a virtual but resonantly enhanced intermediate state. For autocorrelation purposes, the latter configuration improves time resolution whilst partially retaining a resonant enhancement of the two-photon transition strength.

Direct observation of polarons in electron populated quantum dots by resonant Raman scattering

The general problem of the pairing of strongly interacting elementary excitations producing new quasiparticles such as polarons arises in many areas of solid state physics. Recent interest in polaron formation in semiconductor quantum dots has been motivated by the need to understand the physical nature of the carrier relaxation processes and their role in quantum-dot based devices. We report on the direct observation of polarons in InAs/GaAs self-assembled quantum dots populated by few electrons where the polarons are strongly coupled modes of quantum dot phonons and electron intersublevel transitions. The degree of coupling is varied in a systematic way in a set of samples having electron intersublevel spacing changing from larger to smaller than the longitudinal optical phonon energy. The signature of polarons is evidenced clearly by the observation of a large (12-20 meV) anticrossing for both InAs and GaAs-like quantum dot phonons using resonant Raman spectroscopy.

Exposure to low dietary copper or low copper coupled with high dietary manganese for one year does not alter brain prion protein characteristics in the mature cow1,2

It is now widely accepted that abnormal prion proteins are the likely causative agent in bovine spongiform encephalopathy. Cellular prion proteins (PrP(c)) bind Cu, which appears to be required to maintain functional characteristics of the protein. The replacement of Cu on PrP(c) with Mn has resulted in loss of function and increased protease resistance. Twelve mature cows were used to determine the effects of Cu deficiency, alone and coupled with high dietary Mn, on brain Cu and Mn concentrations and on PrP(c) functional characteristics. Copper-adequate cows were randomly assigned to treatments: 1) control (adequate in Cu and Mn), 2) Cu-deficient (-Cu), and 3) Cu-deficient plus high dietary Mn (-Cu+Mn). Cows assigned to treatments -Cu and -Cu+Mn received no supplemental Cu and were supplemented with Mo to further induce Cu deficiency. After 360 d, Cu-deficient cows (-Cu and -Cu+Mn) tended to have lesser concentrations of Cu (P = 0.09) in the obex region of the brain stem. Brain Mn tended (P = 0.09) to be greater in -Cu+Mn cattle compared with -Cu cattle. Western blots revealed that PrP(c) relative optical densities, proteinase K degradability, elution profiles, molecular weights, and glycoform distributions were not different among treatments. The concentration of PrP(c), as determined by ELISA, was similar across treatment groups. Brain tissue (obex) Mn superoxide dismutase activity was greatest (P = 0.04) in cattle receiving -Cu+Mn, whereas immunopurified PrP(c) had similar superoxide dismutase-like activities among treatments. Immunopurified PrP(c) had similar Cu concentrations across treatments, whereas Mn was undetectable. We concluded that Cu deficiency, coupled with excessive Mn intake, in the bovine may decrease brain Cu and increase brain Mn. Copper deficiency, alone or coupled with high dietary Mn, did not cause detectable alterations in PrP(c) functional characteristics.

Antioxidant nature of bovine milk beta-lactoglobulin

Heating is necessary for processing milk in the dairy industry, which evidently produces a conformational change in beta-lactoglobulin (beta-LG). beta-Lactoglobulin, a major protein that accounts for approximately 10 to 15% of total milk proteins, is a globular protein consisting of 162 AA with a relative molecular mass of 18.4 kDa. The purpose of the present study was to determine the antioxidant role of beta-LG in milk and the possible mechanism involved. We showed that beta-LG is a mild antioxidant whose potency is less than that of vitamin E and probucol (the latter being an antioxidant used for clinical therapy). The conversion of the beta-LG monomer to dimer was responsible, in part, for the mode of action in protecting low-density lipoproteins against copper-induced oxidation. Cross-linking the free thiol groups of beta-LG by heating (100 degrees C for 2 min), or chemically modifying the beta-LG by carboxymethylation to block the thiol groups resulted in a substantial loss of antioxidant activity. The data suggest that Cys-121 plays an essential role in the antioxidant nature of beta-LG. By using an anti-LG antibody affinity column to deplete the beta-LG from milk, we observed from the lost antioxidant activity that beta-LG contributes approximately 50% of the total activity. Because beta-LG is extremely sensitive to thermal denaturation, to maintain its antioxidant nature, dairy products consumed daily should not be overheated in order to maintain its antioxidant nature.

Prediction of Alzheimer's disease in mild cognitive impairment: a prospective study in Taiwan

The relationship between apolipoprotein E (ApoE) and clinical manifestations of mild cognitive impairment (MCI) has not been investigated in non-Caucasian populations. This prospective study was conducted in an ethnic Chinese population to evaluate the correlations of ApoE genotype, cognitive performance, medial temporal structure volumes, and clinical outcome in amnestic MCI. Twenty normal elders, 58 MCI, and 20 mild Alzheimer's disease (AD) patients received neuropsychological, MRI, and ApoE genotype assessments at baseline. Patients with MCI had intermediate cognitive performance and hippocampal volumes between those in normal and AD groups. In each diagnostic group, epsilon4 carriers (E4+) consistently had smaller hippocampal volume than non-carriers (E4-) did. Nineteen MCI subjects (32.7%) converted to AD during the 3-year study period. Compared with MCI non-converters and E4- MCI converters, E4+ MCI converters had the smallest hippocampal volume. However, epsilon4 was not a predictor for AD. Both cognitive performance and hippocampal volume were predictive for progression to AD. However, stepwise Cox regression model integrating both neuropsychological and radiological variables showed that global cognitive performance was the only significant predictor for AD. A poor global cognitive score may be more crucial than a small hippocampal volume in the prediction of AD.

Improved treatment results for childhood acute myeloid leukemia in Taiwan

To improve treatment results for children with de novo acute myeloid leukemia (AML), we introduced a novel protocol, Taiwan Pediatric Oncology Group-AML-97A, for AML other than acute promyelocytic leukemia (APL), for which modified conventional protocols were used. From January 1, 1997, to December 31, 2002, 141 children younger than 17 years old with de novo AML were enrolled. In total, 117 patients with non-APL AML were treated with induction therapy of idarubicin and cytarabine (Ara-C), postremission therapy with high-dose Ara-C - containing regimens for four monthly courses, and moderate-dose therapy with idarubicin and Ara-C for four monthly courses. The first 19 patients with APL were treated with all-trans retinoic acid, idarubicin and Ara-C, with the remaining five patients receiving all-trans retinoic acid and idarubicin, followed by maintenance therapy for 2 years. Stem cell transplantation was performed in 29 patients in first remission with a similar outcome as chemotherapy alone. The remission rate in the AML-97A study was 90%, the 5-year survival 51 +/- 5.3% (s.e.) and the 5-year event-free survival 50 +/- 4.8%; for APL, these were 100%, 86 +/- 7.0, and 75 +/- 9.8%. For the whole group, the 5-year survival was 57 +/- 4.7% and the 5-year event-free survival 54 +/- 4.4%. The AML-97A regimen was well tolerated.

Cholinesterase inhibitor affects the amyloid precursor protein isoforms in patients with Alzheimer's disease

An altered platelet ratio of amyloid precursor protein (APP) isoforms might be a diagnostic, predictive, or therapeutic marker for Alzheimer's disease (AD). Our purpose was to test the hypothesis that this ratio might serve as a therapeutic marker for AD patients treated with the cholinesterase inhibitor, galantamine. Thirty-nine patients (mean age 76.6 +/- 9.4 years) with AD were treated with galantamine for 12 weeks. Patients were evaluated at baseline, 4 and 12 weeks by cognitive testing along with a determination of their platelet APP isoform ratio. Western blotting was performed to calculate the APP isoform ratio. At the end of the treatment, cognitive scores significantly improved, and the ratio of the high-molecular-weight (130 kDa) isoform to the low-molecular-weight (110-106 kDa) isoforms increased. These results suggest that cholinesterase inhibition might be involved in APP processing.