A new Kondo antiferromagnet Ce(Ni(0.25)In(1.75))

We find that Ce(Ni(0.25)In(1.75)) crystallizes in the hexagonal AlB(2)-type structure with lattice parameters a = 0.4850(5) nm and c = 0.3908(5) nm. Magnetic susceptibility, electrical resistivity and low-temperature specific heat data reveal that the bulk phase transition at 3.7 ± 0.2 K in Ce(Ni(0.25)In(1.75)) is to an antiferromagnetic state. The magnetic contribution to the resistivity ρ(mag) of Ce(Ni(0.25)In(1.75)) increases as ln(T) when temperature is lowered from room temperature and reaches a plateau at 9 K, followed by a rapid decrease around 4 K. These results associated with a reduction of the Ce magnetic moment and of the magnetic entropy at T(N) suggest that Ce(Ni(0.25)In(1.75)) could be a Kondo antiferromagnet. The Kondo temperature is estimated to be of order 6 K.

Extraordinary transmittance in three dimensional crater, pyramid, and hole-array structures prepared through reversal imprinting of metal films

We used a reversal imprinting-in-metal (RIM) process to fabricate various three-dimensional (3D) metal structures under low pressure. Molds featuring different shapes were used to pattern various subwavelength metal structures, including pyramidal, hole-array, and crater-like structures. Refractive index matching and cavity effects both enhanced the degree of transmission of these structured metal films. The crater-like structure appears to be a promising material because of the unique properties imparted by the elongated and gradually tapering spacing of its cavities. From both near-field simulations and experimentally obtained optical spectra, we found that the cavity effect in the crater-like structure led to significantly enhanced transmission of the optical intensity. Thus, this RIM process allows the ready fabrication of various two- and three-dimensional metallic structures for use in surface plasmon-based devices.

The Severe Cognitive Impairment Rating Scale--an instrument for the assessment of cognition in moderate to severe dementia patients

BACKGROUND/AIMS

This study aimed to develop a brief, reliable and valid test for cognitive function of severely demented patients.

METHODS

We constructed the Severe Cognitive Impairment Rating Scale, which consisted of 11 items covering memory, language, visuospatial function, frontal function and orientation, and investigated its reliability and validity on 267 subjects [normal: 65, very mild Alzheimer's disease (AD): 42, mild AD: 58, moderate AD: 36, severe AD: 44, profound AD: 22].

RESULTS

The internal consistency obtained by Cronbach's coefficient alpha was 0.93. The interrater reliability and test-retest reliability in the moderately to severely impaired subjects with an MMSE score of <or=14 was 0.99 (p < 0.001) and 0.90 (p < 0.001), respectively. It showed significant correlation with Severe MMSE (r = 0.96, p < 0.01), MMSE (r = 0.86, p < 0.01) and Clinical Dementia Rating (r = -0.83, p < 0.01). It was robust to both the floor effect in the severe/profound stage of AD and the ceiling effect in the mild/moderate stage of AD. Exploratory factor analysis yielded 2 factors (automatic informational processing and controlled informational processing) accounting for 73.5% of the total variance.

CONCLUSIONS

The Severe Cognitive Impairment Rating Scale is a valid and reliable test for evaluating the cognitive function of advanced AD patients.

Continuous and discrete stable processes

The one-sided Lévy-stable probability densities and the discrete-stable distributions form a doubly stochastic Poisson transform pair. This relationship facilitates the formulation of a class of continuous-stable stochastic processes.

Extraction and localization of alpha activity of the brain in EEG and fMRI using constrained ICA

In order to extract only the alpha activity related EEG signals of the brain, we have applied constrained Independent Component Analysis (cICA), a new extension of ICA in which some a priori knowledge of alpha activity is utilized to extract desired components. Its performance has been compared to that of conventional band-pass filtering via the scalp power maps of alpha activity. The preliminary results show that cICA-extracted alpha signals produce the alpha power maps which spatially match the activated regions of the brain mapped using fMRI more closely than those from the band-pass filtered alpha EEG signals. The use of cICA might provide a more effective means of extracting EEG alpha activity of the brain.

Methods and evaluations of MRI content-adaptive finite element mesh generation for bioelectromagnetic problems

In studying bioelectromagnetic problems, finite element analysis (FEA) offers several advantages over conventional methods such as the boundary element method. It allows truly volumetric analysis and incorporation of material properties such as anisotropic conductivity. For FEA, mesh generation is the first critical requirement and there exist many different approaches. However, conventional approaches offered by commercial packages and various algorithms do not generate content-adaptive meshes (cMeshes), resulting in numerous nodes and elements in modelling the conducting domain, and thereby increasing computational load and demand. In this work, we present efficient content-adaptive mesh generation schemes for complex biological volumes of MR images. The presented methodology is fully automatic and generates FE meshes that are adaptive to the geometrical contents of MR images, allowing optimal representation of conducting domain for FEA. We have also evaluated the effect of cMeshes on FEA in three dimensions by comparing the forward solutions from various cMesh head models to the solutions from the reference FE head model in which fine and equidistant FEs constitute the model. The results show that there is a significant gain in computation time with minor loss in numerical accuracy. We believe that cMeshes should be useful in the FEA of bioelectromagnetic problems.

The shape control of ZnO based nanostructures

Tetrapod-shape ZnO nanostructures are formed on Si substrates by vapor phase transportation method. The effects of two important growth parameters, growth temperature and VI/II ratio, are investigated. The growth temperature is varied in the range from 600 degrees C to 900 degrees C to control the vapor pressure of group II-element and the formation process of nanostructures. VI/II ratio was changed by adjusting the flux of carrier gas which affects indirectly the supplying rate of group VI-element. From the scanning electron microscopy (SEM), systematic variation of shape including cluster, rod, wire and tetrapod was observed. ZnO tetrapods, formed at 800 degrees C under the carrier gas flux of 0.5 cc/mm2 min, show considerably uniform shape with 100 nm thick and 1-1.5 microm long legs. Also stoichiometric composition (O/Zn - 1) was observed without any second phase structures. While, the decrease of growth temperature and the increase of carrier gas flux, results in the irregular shaped nanostructures with non-stoichiometric composition. The excellent luminescence properties, strong excitonic UV emission at 3.25 eV without deep level emission, indicate that the high crystalline quality tetrapod structures can be formed at the optimized growth conditions.

REVERSIBLE ACTIVATION FOR GERMINATION AND SUBSEQUENT CHANGES IN BACTERIAL SPORES

Lee, W. H. (University of Illinois, Urbana) and Z. John Ordal. Reversible activation for germination and subsequent changes in bacterial spores. J. Bacteriol. 85:207-217. 1963.-It was possible to isolate refractile spores of Bacillus megaterium, from a calcium dipicolinate germination solution, that were activated and would germinate spontaneously in distilled water. Some of the characteristics of the initial phases of bacterial spore germination were determined by studying these unstable activated spores. Activated spores of B. megaterium were resistant to stains and possessed a heat resistance intermediate between that of dormant and of germinated spores. The spontaneous germination of activated spores was inhibited by copper, iron, silver, or mercury salts, saturated o-phenanthroline, or solutions having a low pH value, but not by many common inhibitors. These inhibitions could be partially or completely reversed by the addition of sodium dipicolinate. The activated spores could be deactivated and made similar to dormant spores by treatment with acid. Analyses of the exudates from the variously treated spore suspensions revealed that whatever inhibited the germination of activated spores also inhibited the release of spore material. The composition of the germination exudates was different than that of extracts of dormant spores. Although heavy suspensions of activated spores gradually became swollen and dark when suspended in solutions of o-phenanthroline or at pH 4, the materials released resembled those found in extracts of dormant spores rather than those of normal germination exudates.

Limbs Anthropometry of Singleton Chinese Newborns of 28–42 Weeks’ Gestation

Abnormalities of limbs are important features of some syndromes recognizable at birth. The purpose of this study was to establish normal standards of limbs including arm length, arm circumference, upper arm length, lower arm length, leg length, thigh circumference, upper leg length, and lower leg length. 10,226 infants (5,422 males, 4,804 females) with gestation 28-42 weeks from 12 hospitals were included. The LMS method using maximum penalized likelihood was used to perform model fitting of the anthropometric centiles for these parameters. This study provided the first set of references for the limbs of the infants by gestation and gender. Racial differences were found when comparing with other populations. The parameters are useful for evaluation of morphologic disorders involving the limbs.

Trunk anthropometry of Hong Kong Chinese infants

BACKGROUND

Disturbed growth of the trunk may result in abnormal sternocostal relationship and a variety of pectus deformities.

AIMS

The purposes of this study were to establish norms of trunk anthropometry for dysmorphology identification in the newborns and to evaluate chest circumference as a predictor for low birth weight for outborn infants where weighing scales were unavailable.

STUDY DESIGN AND SUBJECTS

A total of 10,339 Chinese infants (5478 males, 4861 females) with gestation 24-42 weeks from 12 hospitals were included. The anthropometric measurements analyzed included chest circumference, inter-nipple distance, sternal length and abdominal circumference.

OUTCOME MEASURES

The LMS method using maximum penalized likelihood was used to perform model fitting of the anthropometric centiles for these physical parameters.

RESULTS

References tables of the four physical parameters for newborns were constructed. Chest circumference showed the highest correlation with birth weight (male: r = 0.866, female: r = 0.883). The cut-off points for chest circumference of 295 (male) and 299 mm (female) were the best predictor for low birth weight. There were also racial differences in these parameters. When compared with French infants, Chinese newborns had smaller chest circumference.

CONCLUSION

These physical parameters provide useful references and aid dysmorphology diagnosis in newborns of ethnic Chinese origin.

Molecular models of the procoagulant factor VIIIa-factor IXa complex

BACKGROUND

Formation of the intrinsic tenase complex is an essential event in the procoagulant reactions that lead to clot formation. The tenase complex is formed when the activated serine protease, Factor IXa (FIXa), and its cofactor Factor VIIIa (FVIIIa) assemble on a phospholipid surface to proteolytically convert the zymogen Factor X (FX) into its active form FXa. The physiological relevance of the tenase complex is evident in hemophilia A or B patients who present with bleeding disorders.

OBJECTIVES

The purpose of this study was to establish three-dimensional (3D) models of the FVIIIa-FIXa complex.

METHODS

First, we built two new theoretical models of FVIIIa via homology modeling, inter-domain docking and loop simulation algorithms as well as a model for FIXa. This was followed by pseudo-Brownian protein-protein docking in internal coordinates with the ICM (Internal Coordinates Mechanics) program between the two FVIIIa and the FIXa structures.

RESULTS

Ten representative models of this complex are presented based on agreements with known experimental data and according to structural criteria.

CONCLUSIONS

These novel 3D models will help guide future site directed mutagenesis aimed at improving the functionality of FVIIIa and/or FIXa and will contribute to a better understanding of the role of this macromolecular complex in the blood coagulation cascade.

Normative Data of Penile Length for Term Chinese Newborns

Careful examination and assessment of penile length in the newborn is important because micropenis is associated with hypothalamic disorders. This prospective cross-sectional study was designed to establish the norm of penile length for term Hong Kong Chinese newborns. 4,628 full-term healthy male newborns were enrolled in the study. Penile length was measured from pubic ramus to the tip of the glans penis by placing the end of a straight edge ruler against the pubic ramus. A gestation-associated graph of 3rd, 10th, 25th, 50th, 75th, 90th and 97th centiles for the penile length was created. The penile length was significantly correlated with gestational age, birth weight and body length. When compared with published data for other populations, Hong Kong newborns have significantly shorter penile length. The norm of the penile length is useful in diagnostic and therapeutics for the ethnic Chinese male newborns.

Fetal growth velocities in Hong Kong Chinese infants

Few studies have investigated the velocities of fetal growth. The aim of the present study was to determine the pattern of 'fetal' growth velocities in a Chinese population. The gestation-specific measurements of the body weight, body length and head circumference in a representative sample of 5,045 male and 4,484 female newborns delivered between 26 and 42 weeks of gestation at 12 hospitals in Hong Kong were obtained. Peak growth velocity occurred before 30 weeks of gestation for head circumference, at week 30 for length and at week 30 for weight. When compared with data obtained from a French population, a significant difference in the growth velocity for body weight was observed below 32 weeks between French and Chinese infants, suggesting an ethnic difference in fetal growth of this parameter.

Role of NADP+-dependent isocitrate dehydrogenase (NADP+-ICDH) on cellular defence against oxidative injury by gamma-rays

PURPOSE

To investigate the regulation of NADPH-producing isocitrate dehydrogenase (ICDH) in cytosol (IDPc) and mitochondria (IDPm) upon gamma-ray irradiation, and the roles of IDPc and IDPm in the protection against cellular damage induced by gamma-ray irradiation.

MATERIALS AND METHODS

Changes of IDPc and IDPm proteins upon gamma-ray irradiation to NIH3T3 cells were analysed by immunoblotting. To increase or decrease the expression of IDPc or IDPm, NIH3T3 cells were stably transfected with mouse IDPc or IDPm cDNA in either the sense or the antisense direction. The transfected cells with either increased or decreased IDPc or IDPm were exposed to gamma-rays, and the levels of reactive oxygen species generation, protein oxidation and lipid peroxidation were measured.

RESULTS

Both IDPc and IDPm activities were induced by gamma-ray in NIH3T3 cells. Cells with decreased expression of IDPc or IDPm had elevated reactive oxygen species generation, lipid peroxidation and protein oxidation. Conversely, overproduction of IDPc or IDPm protein partially protected the cells from oxidative damage induced by gamma-ray irradiation.

CONCLUSIONS

The protective role of IDPc and IDPm against gamma-ray-induced cellular damage can be attributed to elevated NADPH, reducing equivalents needed for recycling reduced glutathione in the cytosol and mitochondria. Thus, a primary biological function of the ICDHs may be production of NADPH, which is a prerequisite for some cellular defence systems against oxidative damage.

Analysis of genes responding to ultraviolet B irradiation of HaCaT keratinocytes using a cDNA microarray

BACKGROUND

Ultraviolet (UV) B irradiation causes many important biological changes in skin, which lead to pathophysiological alterations of the homeostatic environment.

OBJECTIVES

To gain more insight into the molecular events provoked by UVB irradiation, we performed cDNA microarray analysis.

METHODS

Immortalized HaCaT keratinocytes were irradiated with a high cytotoxic dose of UVB (50 mJ cm(-2)), and total RNA was isolated. Fluorescently labelled probes were prepared by reverse transcription and were hybridized with cDNA microarray slides made using 840 cDNA clones.

RESULTS

Time-course cDNA microarray analysis revealed the global gene expression profile after UVB exposure. Of 840 genes tested, 192 genes showed changes in their expression levels at one or more of four time points. The genes were clustered into four groups according to their expression patterns in a self-organizing maps analysis. Classification of these genes into nine functional categories revealed that UVB irradiation affected several biological processes. The genes that were first upregulated and then returned to normal levels included several genes related to the inhibition of cell growth and the proteasome pathway. Conversely, the expressions of many genes involved in the cytoskeleton, signal transduction, metabolism and transcription were first downregulated or unchanged and then upregulated later, reflecting the recovery of UVB-damaged cellular activities.

CONCLUSIONS

These results demonstrate the complexity of the transcriptional profile of the UVB response, and provide a basis for the global characterization of UV-regulated gene expression.

Immunomodulating Effects of CKBM on the Cytokine Production in Peripheral Blood Mononuclear Cells (PBMCs) from Healthy Volunteers

The current study investigated the immunomodulating effect of CKBM on cytokine induction in peripheral blood mononuclear cells (PBMCs) isolated from 20 healthy volunteers. Cytometric Bead Analysis (CBA) was used to study IL-2, IL-4, IL-6, IL-10, TNF-alpha and IFN-gamma. TNF-alpha and IL-6 were significantly increased in a CKBM dose- and time-dependent manner. Flow cytometry analysis showed an increased intracellular staining of IL-6 but not of TNF-alpha in CKBM treated PBMCs. In addition, MTT cell cytotoxicity assay showed that CKBM concentrations below 5% did not significantly affect the metabolic activities of PBMCs. The current study indicated that CKBM may modulate the immune response by inducing the secretions of TNF-alpha and IL-6, which are cytokine mediators of innate immunity and inflammation preparing or "priming" the body to combat diseases.

Heterogeneity detector: finding heterogeneous positions in Phred/Phrap assemblies

A modification to Phred and program to detect heterogeneous positions, which is particularly useful in the identification of mutations and other abnormalities in Phred/Phrap genome assemblies.

AVAILABILITY

The package is made available at http://glscompute.gis.a-star.edu.sg/~charlie/DHetero.html

A rare cause of intestinal perforation in an extreme low birth weight infant--gastrointestinal mucormycosis: a case report

We report an extreme low birth weight infant with gastrointestinal mucormycosis (GM) mimicking necrotizing enterocolitis on day 15 of age. Emergency laparotomy confirmed ileal perforations. Subsequently, tissue histology confirmed GM. This is the most premature infant who survived after GM and is the third reported neonatal survivor in English literature.

Maternal diclofenac sodium ingestion and severe neonatal pulmonary hypertension

We describe a case of severe pulmonary hypertension and transient right-sided hypertrophic cardiomyopathy in a neonate, caused by premature closure of ductus arteriosus after short-term maternal use of diclofenac sodium (Voltaren). In view of this associated complication, diclofenac sodium should be avoided during pregnancy. In addition, maternal diclofenac sodium ingestion should be suspected if a newborn develops severe pulmonary hypertension and/or right-sided hypertrophic cardiomyoptathy with closed ductus arteriosus.

Ammonium nitrogen removal from slurry-type swine wastewater by pretreatment using struvite crystallization for nitrogen control of anaerobic digestion

Precipitation of ammonium together with phosphate and magnesium is a possible alternative for lowering the nitrogen content of wastewater. In this study we examine the removal of ammonium nitrogen and phosphorus from slurry-type swine wastewater containing high concentrations of nutrients by the addition of phosphoric acid along with either calcium oxide or magnesium oxide, which leads to the crystallization of insoluble salts such as hydroxyapatite and struvite. The struvite crystallization method showed a high capacity for the removal of nitrogen when magnesium oxide and phosphoric acid were used as the magnesium and phosphate sources, respectively. When it was applied to swine wastewater containing a high concentration of nitrogen, the injection molar ratio of Mg2+:NH4+:PO4(3-) that gave maximum ammonium nitrogen removal was 3.0:1.0:1.5.

Updated gestational age specific birth weight, crown-heel length, and head circumference of Chinese newborns

OBJECTIVE

To construct gestation specific standards of birth weight, crown-heel length, and head circumference of Chinese infants.

DESIGN

A prospective cross sectional population study.

METHODS

The birth weight, crown-heel length, and head circumference were prospectively measured using standard equipment in newborns delivered at 24-42 weeks gestation in the maternity units of 10 public hospitals and two private hospitals in Hong Kong. The findings were used to construct gestation specific standards of these variables. The LMS method using maximum penalised likelihood was used to perform model fitting. The results were compared with those obtained from a cohort of infants born in the same locality between 1982 and 1986.

RESULTS

From October 1998 to September 2000, a total of 10 032 infants were measured, representing 9.6% of the total deliveries in Hong Kong during that period. An extra 307 infants with gestation < or = 35 weeks were recruited from October 2000 to June 2001. Each of the three variables showed a normal distribution at each gestational week. Gestation specific reference standards for each variable were constructed for male and female infants separately. Comparison with the 1982-1986 cohort showed a significant secular trend to increased birth weight. The trend was small, but significant, for crown-heel length and head circumference.

CONCLUSION

These growth standards will provide useful references for the care of newborns of ethnic Chinese origin. These standards, especially that for birth weight, should be updated regularly.

A double-blind, randomised- placebo, controlled, parallel group, multicentre, flexible-dose escalation study to assess the efficacy and safety of sildenafil administered as required to male outpatients with erectile dysfunction in Korea

The efficacy and safety of sildenafil was evaluated in a randomiSed, double-blind, placebo-controlled, flexible-dose study in Korean men aged 28-78 y with erectile dysfunction (ED) of broad-spectrum aetiology and more than 6 months duration. A total of 133 patients were randomised at six centres in Korea to receive either sildenafil (50 mg initially, increased if necessary to l00 mg or decreased to 25 mg depending on efficacy and tolerance) (n=66) or matching placebo (n=67) taken on an 'as needed' basis l h prior to anticipated sexual activity for a period of 8 weeks. At the end of this time, the primary efficacy variables relating to the achievement and maintenance of erections sufficient for sexual intercourse, and the secondary efficacy variables, which included: (1) the five separate domains of sexual functioning of the International Index of Erectile Function (IIEF) scale, (2) the percentage of successful intercourse attempts, and (3) a global assessment of erections, were all statistically significantly improved by sildenafil in comparison with placebo (P&<0.0001). Treatment-related adverse events occurred in 56.1% of patients receiving sildenafil and 20.9% receiving placebo. The most common adverse events with sildenafil were vasodilatation (flushing), headache and abnormalities in colour vision (31.8, 22.7 and 6.1% of patients, respectively), and most were mild in nature. The efficacy and safety of sildenafil in this population of Korean men appears similar to that reported in other studies in western populations.

Polyhydroxyalkanoate (PHA) production from waste

PHA (polyhydroxyalkanoate) production was attempted with SBRs from food waste. Seed microbes were collected from a sewage treatment plant with a biological nutrient removal process, and acclimated with synthetic substrate prior to the application of the fermented food waste. Laboratory SBRs were used to produce PHA with limited oxygen and nutrients. The maximum content of 51% PHA was obtained with an anaerobic/aerobic cycle with P limitation, and the yield was estimated to be about 0.05 gPHA(produced)/gCOD(applied) or 25 kg PHA/dry ton of food waste, assuming more than 40% of the PHA contents were recoverable. PHB/PHA ratios were 0.74 to 0.77 due to the higher acetate concentrations. Economical analysis seemed to suggest the PHA produced from the food waste could be an alternative material to produce the biodegradable plastic to be used for the collection bags for solid waste.

Identification of new endogenous retroviral sequences belonging to the HERV-W family in human cancer cells

A human endogenous retroviral family (HERV-W) has recently been identified on chromosome 7 that contains a single complete open reading frame putatively encoding an envelope protein. We have identified fifteen HERV-W families on human genomic DNA using a monochromosomal panel in our previous study. In order to identify additional families, we examined genomic DNA derived from cancer cell lines (A549, AZ521, OVCAR3, RT4) using the PCR approach. Five env fragments of a HERV-W family were newly identified and analyzed. They showed a high degree of nucleotide sequence similarity (93-97%) to that of the other HERV-W families. Translation of the env fragments showed no frameshift and termination codon by deletion/insertion or point mutation in clones A549-2, AZ521-3, and OVCAR-3. The ratio of synonymous to nonsynonymous substitutions indicated that negative selective pressure is acting on A549-2, AZ521-3, and OVCAR-3 sequences. These env gene sequences could be associated with an active provirus in human cancer cells (A549, AZ521, OVCAR3).