Preladenant, a selective adenosine A₂A receptor antagonist, is not associated with QT/QTc prolongation

PURPOSE

Preladenant is an orally administered adenosine2A (A2A) receptor antagonist in phase III development for Parkinson's disease treatment. This thorough QT/QTc study evaluated its potential effects on cardiac repolarization.

METHODS

This was a randomized, double-blind, positive- and placebo-controlled, four-period crossover study performed under steady-state exposure of clinical and supratherapeutic doses of preladenant (10 mg BID and 100 mg BID, respectively, for 5 days), moxifloxacin (400 mg on day 5), or placebo in 60 healthy adult volunteers. The potential effect on QTcF was measured by the largest upper bound of 95 % one-sided CIs for the mean changes from time-matched baseline ECG recordings compared with placebo. Plasma preladenant concentrations were also determined on day 5.

RESULTS

The QTcF difference for moxifloxacin compared with placebo exceeded 5 ms from 1 to 12 h postdose, establishing assay sensitivity. The QTcF interval was similar between the preladenant and placebo treatment groups: the upper bound of the 95 % one-sided CI for the mean difference in QTcF between preladenant and placebo was less than 10 ms at all time points for the supratherapeutic treatment group (1.3 to 5.7 ms, mean difference: -1.3 to 2.7 ms) and the therapeutic treatment group (0.4 to 4.3 ms, mean difference: -2.1 to 1.5 ms), substantially below the threshold of regulatory concern. The supratherapeutic dose (100 mg BID) provided a Cmax margin of 6.1-fold and AUC margin of 6.9-fold, respectively, compared with 10 mg BID.

CONCLUSIONS

At clinical and supratherapeutic doses, preladenant is not associated with QTc prolongation.

In situ UV-crosslinking gelatin electrospun fibers for tissue engineering applications

Electrospun fibers of natural polymers are desirable for biomedical applications such as tissue engineering. Crosslinking of electrospun fibers of natural polymers is needed to prevent dissolution in water and to enhance mechanical strength. In this study, an in situ UV-crosslinking method was developed for crosslinking of gelatin electrospun fibers (GESFs) and water-soluble synthetic polymers. A mixture of gelatin and phenylazide-conjugated poly(acrylic acids) was electrospun under UV irradiation. The UV-crosslinked GESFs were not dissolved in water with improved mechanical strength. Compared to traditional crosslinking by glutaraldehyde vapor, the GESFs crosslinked by our method are superior in terms of retention of GESF morphology, uniform crosslinking throughout the fibers, low cytotoxic and retention of biofunctionality. L929 cells grew better on the UV-crosslinked GESF scaffolds compared to glutaraldehyde-crosslinked ones. Furthermore, bioactive nanoparticles, e.g. hydroxyapatite, could be incorporated into GESFs for enhancing osteoconductivity, which possess a great potential in bone tissue engineering.

Role of K1 capsule antigen in cirrhotic patients with Escherichia coli spontaneous bacterial peritonitis in southern Taiwan

Spontaneous bacterial peritonitis (SBP) is one of the most serious complications in patients with cirrhosis. This study aimed to investigate the prevalence of SBP caused by Escherichia coli isolates with or without the K1 capsule antigen in cirrhotic patients and the outcome. From January 2004 to January 2012, a total of 54 and 41 E. coli strains derived from patients with SBP and intestinal perforation (IP), respectively, were included for comparison in this study. Bacterial characteristics including phylogenetic groups, K1 capsule antigen, and 14 virulence factor genetic determinants, as well as data regarding patient characteristics, clinical manifestations, and in-hospital deaths, were collected and analyzed. The prevalence of the K1 capsule antigen gene neuA was more common in SBP isolates compared to IP isolates (28 % vs. 10 %, p = 0.0385). Phylogenetic groups B2 and group D were dominant in E. coli isolates with and without the K1 capsule antigen, respectively. The prevalence of virulence factors genes papG II, ompT, and usp was higher in E. coli K1 strains. There were 26 deaths (48 %) during hospitalization. Presence of the K1 capsule antigen in E. coli isolates was significantly associated with in-hospital death in cirrhotic patients with SBP (42 % vs. 14 %, p = 0.0331). This study demonstrates a higher prevalence of the K1 capsule antigen in E. coli SBP compared to E. coli peritonitis caused by IP. There were significant associations between the K1 capsule antigen and in-hospital mortality and bacterial virulence in cirrhotic patients with E. coli SBP.

Field-induced expansion deformation in Pb islands on Cu(111): evidence from energy shift of empty quantum-well states

We use scanning tunneling microscopy and spectroscopy to measure the energy shift of empty quantum-well (QW) states in Pb islands on the Cu(111) surface. It is found that, with an increase of the electric field, the behavior of the energy shift can be grouped into two different modes for most QW states. In the first mode, the state energy moves toward high energy monotonically. In the second mode, the state energy shifts to a lower energy initially and then turns around to a higher energy. Moreover, we have observed that the QW states of higher energy behave in preference to the first mode, but they gradually change to the second mode as the Pb island becomes thicker. This thickness-dependent behavior reflects the existence of local expansion in the Pb islands, due to the electric field, and that the expansion is larger for a thicker island. QW states can thus be used for studying the localized lattice deformation in the nanometer scale.

Cytotoxic metabolites from the fungal endophyte Alternaria sp. and their subsequent detection in its host plant Polygonum senegalense

From the Egyptian medicinal plant Polygonum senegalense the fungal endophyte Alternaria sp. was isolated. Extracts of the fungus grown either in liquid culture or on solid rice media exhibited cytotoxic activity when tested in vitro against L5178Y cells. Chromatographic separation of the extracts yielded 15 natural products, out of which seven were new compounds, with both fungal extracts differing considerably with regard to their secondary metabolites. Compounds 1, 2, 3, 6, and 7 showed cytotoxic activity with EC 50 values ranging from 1.7 to 7.8 microg/mL. When analyzed in vitro for their inhibitory potential against 24 different protein kinases, compounds 1- 3, 5- 8, and 15 inhibited several of these enzymes (IC 50 values 0.22-9.8 microg/mL). Interestingly, compounds 1, 3, and 6 were also identified as constituents of an extract derived from healthy leaves of the host plant P. senegalense, thereby indicating that the production of natural products by the endophyte proceeds also under in situ conditions within the plant host.

Association between sleep quality and physical fitness in female young adults

AIM

Sleep quality and physical fitness are critical for young adults' growth and health. However, no study has examined the association between sleep quality and physical fitness in young adults.

METHODS

A total of 291 female college students (mean age: 19.3+/-0.6 years; mean height: 160.3+/-5.2 cm; mean weight: 52.2+/-9.8 kg), in the northern part of Taiwan, volunteered as subjects. For sleep quality evaluation, a valid Chinese version of the Pittsburgh Sleep Quality Index (PSQI) was used. For physical fitness testing, a battery of field-based health-related fitness tests was conducted by well-trained instructors. Data was analyzed using independent t-tests and the Pearson product-moment correlation coefficient.

RESULTS

Subjects with poor sleep quality (P) (PSQI score >5) were more likely to have lower levels of muscular endurance, flexibility, and cardiovascular fitness. Significant correlations were also found between the global PSQI score and physical fitness performances in female young adults.

CONCLUSION

This study confirmed the high prevalence of P among young adults. Education materials should try to prevent young adults from developing poor sleep patterns and inactive lifestyles. Moreover, subjects with P should take better care of health problems from cardiovascular disease and musculoskeletal injury.

Association study of genetic polymorphisms of SLC2A10 gene and type 2 diabetes in the Taiwanese population

AIMS/HYPOTHESIS

The gene encoding solute carrier family 2, facilitated glucose transporter, member 10 (SLC2A10, previously known as glucose transporter 10 [GLUT10]) is a promising candidate gene for type 2 diabetes since it is highly expressed in liver and pancreas and is located on human chromosome region 20q12-q13.1, a region previously shown to harbour type 2 diabetes susceptibility genes. We investigated whether the SLC2A10 gene could be a type 2 diabetes susceptibility gene in the Taiwanese population.

SUBJECTS AND METHODS

Sequencing of SLC2A10 gene from 48 diabetic subjects detected short tandem repeat polymorphisms in the promoter region, but did not detect any other sequence variants or new single-nucleotide polymorphisms (SNPs) other than those already in the SNPper database ( http://snpper.chip.org ) (30 June 2005).

RESULTS

Using these genetic polymorphisms, we divided the SLC2A10 gene into four distinct linkage disequilibrium blocks and performed a case-control association study in a group of type 2 diabetes subjects (n = 375) and normoglycaemic individuals (n=377). The HapD (A-G-T-C) haplotype in block 3, a rare haplotype, which consisted of four SNPs (rs3092412, rs2235491, rs2425904 and rs1059217), was modestly associated with type 2 diabetes with a haplotype score of -2.95567 (p = 0.012 with the haplotype-specific test).

CONCLUSIONS/INTERPRETATION

Our results suggest that SLC2A10 genetic variations do not appear to be major determinants for type 2 diabetes susceptibility in the Taiwanese population.

The role of quorum sensing and the effect of environmental conditions on biofilm formation by strains of Vibrio vulnificus

It has been suggested that Vibrio vulnificus attaches to plankton and algae and is found in large numbers in the environment. Factors affecting attachment, biofilm formation and morphology of V. vulnificus have not been thoroughly investigated. This study evaluated the role of quorum sensing (QS) and environmental conditions on biofilm development of V. vulnificus. It was found that biofilm development by V. vulnificus was affected by nutrient and glucose concentration, but not by NaCl concentration or temperature under the conditions used here. Moreover, biofilm development of a QS mutant strain proceeded rapidly and sloughing occurred earlier than for the isogenic parent strain. There was a significant loss of viability for the QS mutant biofilm early in development. Hence, it is hypothesised that factors regulated by the QS system play a role in proper biofilm development and maintenance of V. vulnificus. Furthermore, it is shown that biofilm development varied among isolates.

New natural products from the sponge-derived fungus Aspergillus niger

Fractionation of the EtOAc extract of a static culture of Aspergillus niger isolated from the Mediterranean sponge Axinella damicornis yielded eight secondary metabolites, out of which seven compounds (2-8) proved to be new natural products, whereas one was identified as the known fungal pigment cycloleucomelone (1). The new compounds included the 3,3'-bicoumarin bicoumanigrin (2), the structurally unusual 4-benzyl-1H-pyridin-6-one derivatives aspernigrins A and B (3 and 4), and pyranonigrins A-D (5-8), the latter featuring a novel pyrano[3,2-b]pyrrole skeleton hitherto unprecedented in nature. All structures were elucidated on the basis of extensive one- and two-dimensional NMR spectroscopic studies ((1)H, (13)C, COSY, HMQC, HMBC, NOE difference spectra) and mass spectral analysis. For the two chiral molecules 4 and 5, the absolute configurations were established by quantum chemical calculations of their circular dichroism (CD) spectra. In each case, two independent methods, i.e., a molecular dynamics approach taking into consideration the molecular flexibility, and a conformational analysis followed by Boltzmann weighting of the single CD spectra calculated for the conformers thus obtained, led to identical results without the need of any empirical comparison of chiroptical data reported for reference compounds. Bicoumanigrin (2) showed moderate cytotoxicity against human cancer cell lines in vitro. In addition, aspernigrin B (4) was found to display a strong neuroprotective effect against glutamic acid.

Q/R RNA editing of the AMPA receptor subunit 2 (GRIA2) transcript evolves no later than the appearance of cartilaginous fishes

The amino acid, either a glutamine (Q) or an arginine (R), at the Q/R site of the pore-lining segment (M2) of a vertebrate AMPA receptor subunit critically influences the properties of the receptor. The R codon of the mammalian AMPA receptor subunit 2 (GRIA2) transcript is not coded by the chromosomal sequence, but is created by posttranscriptional RNA editing activities. On the other hand, the R codons of some teleost GRIA2 homologs are coded by chromosomal sequences. To elucidate the evolution of the utilization of Q/R RNA editing in modifying vertebrate GRIA2 transcripts, the GRIA2 genes of five fish species and an amphibian were studied. The putative hagfish GRIA2 homolog (hfGRIA2) encodes an R codon, whereas shark and bullfrog GRIA2 genes specify a Q codon at the genomic Q/R site. All gnathostoma GRIA2 genes possess an intron splitting the coding regions of M2 and the third hydrophobic region (M3). The intronic components required for Q/R RNA editing are preserved in all the Q-coding vertebrate GRIA2 genes but are absent from the R-coding GRIA2 genes. Interestingly, the hfGRIA2 is intronless, suggesting that hfGRIA2 is unlikely evolved from a Q/R editing-competent gene. Results of this study suggest that modification of GRIA2 transcripts by Q/R editing is most likely acquired after the separation of the Agnatha and Gnathostome.

Identifications, classification, and evolution of the vertebrate alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) receptor subunit genes

The AMPA receptor (AMPAR), a pharmacologically defined ionotropic glutamate receptor, mediates fast excitatory synaptic transmission in the vertebrate central nervous system. Mammalian and avian AMPARs are assembled from the products of four genes (GRIA1-GRIA4) conserved in their translated sequences and gene organizations. Teleost fish also express AMPAR subunits; however, the AMPAR genes have not been extensively investigated in lower vertebrates. To elucidate the evolution of vertebrate AMPAR genes, reverse-transcriptase PCR-based surveys of subunits expressed in the brains of eight nonmammalian vertebrates were performed. The newly cloned vertebrate AMPAR subunits were classified by their sequence identities to the mammalian AMPAR subunits. The results of molecular and phylogenetic analyses indicated that the members of the AMPAR gene family increased from two in the jawless hagfish to four in the tetrapods and the shark and to more than four in the teleost fish. The sizes of AMPAR gene families correlate well with those of many multigene families observed in various vertebrates. Moreover, all vertebrates expressed at least one AMPAR subunit bearing an arginine (R) at the Q/R site, at which no invertebrate glutamate receptor subunit has been found to have an R residue, suggesting that the low calcium-permeable AMPARs appeared at early evolutionary stages of vertebrate central nervous systems. Uniquely, the loop 1 (L1) regions between hydrophobic domain 1 and hydrophobic domain 2 of the hagfish putative GRIA2 and all the teleost GRIA1 subunits were much longer than those of the remaining known ionotropic glutamate receptor subunits. The length and sequence of the L1 of teleost GRIA1 subunits were heterogeneous, suggesting that the amino acid residues in L1 were not highly selected.

Rocaglamides, glycosides, and putrescine bisamides from Aglaia dasyclada

A phytochemical analysis of the leaves of Aglaia dasyclada collected in Yunnan Province (People's Republic of China) yielded five cyclopentabenzofurans (1-5) of the rocaglamide family that are common secondary metabolites of Aglaia species as well as four biogenetically related compounds of the aglain (7), aglaforbesin (8) and forbaglin (9, 10) types. In addition, the cinnamic acid amide dasyclamide (6), which is a putative biogenetic precursor of these compounds (7-10), was isolated. The structures of the new compounds (6-10) were assigned unambiguously from the combined use of 1D and 2D NMR spectroscopy and mass spectrometry.

Inverted repeats as genetic elements for promoting DNA inverted duplication: implications in gene amplification

Inverted repeats are important genetic elements for genome instability. In the current study we have investigated the role of inverted repeats in a DNA rearrangement reaction using a linear DNA substrate. We show that linear DNA substrates with terminal inverted repeats can efficiently transform Escherichia coli. The transformation products contain circular inverted dimers in which the DNA sequences between terminal inverted repeats are duplicated. In contrast to the recombination/rearrangement product of circular DNA substrates, which is exclusively one particular form of the inverted dimer, the rearrangement products of the linear DNA substrate consist of two isomeric forms of the inverted dimer. Escherichia coli mutants defective in RecBCD exhibit much reduced transformation efficiency, suggesting a role for RecBCD in the protection rather than destruction of these linear DNA substrates. These results suggest a model in which inverted repeats near the ends of a double-strand break can be processed by a helicase/exonuclease to form hairpin caps. Processing of hairpin capped DNA intermediates can then yield inverted duplications. Linear DNA substrates containing terminal inverted repeats can also be converted into inverted dimers in COS cells, suggesting conservation of this type of genome instability from bacteria to mammalian cells.

Suppression of gene amplification and chromosomal DNA integration by the DNA mismatch repair system

Mismatch repair (MMR)-deficient cells are shown to produce >15-fold more methotrexate-resistant colonies than MMR normal cells. The increased resistance to methotrexate is primarily due to gene amplification since all the resistant clones contain double-minute chromosomes and increased copy numbers of the DHFR gene. In addition, integration of linearized or retroviral DNAs into chromosomes is also significantly elevated in MMR-deficient cells. These results suggest that in addition to microsatellite instability and homeologous recombination, MMR is also involved in suppression of other genome instabilities such as gene amplification and chromosomal DNA integration.

Molecular scanning of the human sorbin and SH3-domain-containing-1 (SORBS1) gene: positive association of the T228A polymorphism with obesity and type 2 diabetes

In the mouse, the SH3P12 or the c-Cbl-associated protein (CAP) has been shown as an important signaling molecule in insulin-stimulated glucose uptake. The human homolog for the sorbin and SH3-domain-containing-1 gene, termed SORBS1, might play a role in human disorders with insulin resistance. To explore the genetic role of SORBS1 in human obesity and type 2 diabetes, we investigated the nucleotide polymorphisms in the SORBS1 gene with molecular scanning. After scanning for a total of 13,136 bp in each of 40 chromosomes, we have identified 14 single nucleotide polymorphisms (SNPs) in the human SORBS1 gene. Among them, two SNPs affected amino acid coding (R74W and T228A), four occurred within exons but did not affect amino acid coding, and the remaining eight occurred within introns, which were located outside of the consensus region of the splicing mechanism. Further studies in 202 non-obese, 113 obese and 455 subjects with type 2 diabetes revealed that the A-allele of the T228A polymorphism in exon 7 exerted a protective role for both obesity [relative risk 0.466; 95% confidence interval (95% CI) 0.265-0.821] and diabetes (relative risk 0.668; 95% CI 0.472-0.945). Neither allele of the R74W polymorphism was associated with either obesity or diabetes. In conclusion, our results suggest that the A228 allele of the T228A polymorphism of the SORBS1 gene is a protective factor for both obesity and diabetes, and also imply that the SORBS1 gene plays an important role in the pathogenesis of human disorders with insulin resistance.

Comparison of conventional phototherapy and fiberoptic phototherapy in the very-low-body-weight infants

Phototherapy is effectively employed for the treatment of neonatal hyperbilirubinemia, but it may influence the physiological hemodynamics of the infants, such as skin blood flow, insensible water loss and the redistribution of cardiac output. This is a retrospective chart review study involved totally 42 very low birth weight prematures(birth body weight less than 1500 gm, VLBW) who received conventional or fiberoptic phototherapy. Infants with congenital malformation, severe cardiorespiratory instability and the requirement of diuretics, inotropics or blood transfusion were excluded. The body weight loss, daily intake/output and bilirubin level during the initial four days of phototherapy were analyzed. The results showed the efficacy of both methods was the same, while the fiberoptic therapy group had significantly more urine output(p < 0.05), the body weight loss was not statistically significant. It is possible that the fiberoptic therapy group had less insensible water loss and less attenuation of the decrease of renal blood flow, this resulted in more urine output.

Cloning, Mapping, and Characterization of the Human Sorbin and SH3 Domain Containing 1 (SORBS1) Gene: A Protein Associated with c-Abl during Insulin Signaling in the Hepatoma Cell Line Hep3B

SH3P12/CAP/ponsin, a gene product with a sorbin homology domain and three consecutive SH3 domains in the carboxy-terminus, has been isolated from murine adipocytes and identified as an important adaptor during insulin signaling. Here we describe the cloning, mapping, and expression of the human homologue, termed SORBS1 (sorbin and SH3 domain containing 1). Multiple transcripts of this gene with different mRNA isoforms were observed among different tissues. Here we report 13 alternatively spliced exons, which were ascertained from the full-length cDNA cloned in adipose, liver, and skeletal muscle tissues. Among the major isoforms, the shortest, 2223-bp, open reading frame (ORF) encodes a protein with a predicted molecular weight of 81.5 kDa, while the longest, 3879-bp, ORF encodes a protein of about 142.2 kDa. This gene was mapped to human chromosome 10q23.3-q24.1, which is a candidate region for insulin resistance found in Pima Indians. In human hepatoma Hep3B cells, SORBS1 was partly dissociated from the insulin receptor complex and bound to c-Abl protein upon insulin stimulation. This interaction with c-Abl was through the third SH3 domain and a possible conformational change of SORBS1 induced by insulin. Our data suggest that c-Abl oncoprotein via SORBS1 might play a role in the insulin signaling pathway.

Least-squares Legendre spectral element solutions to sound propagation problems

This paper presents a novel algorithm and numerical results of sound wave propagation. The method is based on a least-squares Legendre spectral element approach for spatial discretization and the Crank-Nicolson [Proc. Cambridge Philos. Soc. 43, 50-67 (1947)] and Adams-Bashforth [D. Gottlieb and S. A. Orszag, Numerical Analysis of Spectral Methods: Theory and Applications (CBMS-NSF Monograph, Siam 1977)] schemes for temporal discretization to solve the linearized acoustic field equations for sound propagation. Two types of NASA Computational Aeroacoustics (CAA) Workshop benchmark problems [ICASE/LaRC Workshop on Benchmark Problems in Computational Aeroacoustics, edited by J. C. Hardin, J. R. Ristorcelli, and C. K. W. Tam, NASA Conference Publication 3300, 1995a] are considered: a narrow Gaussian sound wave propagating in a one-dimensional space without flows, and the reflection of a two-dimensional acoustic pulse off a rigid wall in the presence of a uniform flow of Mach 0.5 in a semi-infinite space. The first problem was used to examine the numerical dispersion and dissipation characteristics of the proposed algorithm. The second problem was to demonstrate the capability of the algorithm in treating sound propagation in a flow. Comparisons were made of the computed results with analytical results and results obtained by other methods. It is shown that all results computed by the present method are in good agreement with the analytical solutions and results of the first problem agree very well with those predicted by other schemes.

Plasma concentrations of leptin and selected minerals do not differ in Type 2 diabetic patients with or without sulfonylurea inefficacy

The oral hypoglycemic agent sulfonylurea (SU) can increase plasma leptin concentrations. Additionally, diabetic subjects frequently have an altered plasma status of selected minerals. However, whether these described plasma parameters are changed in Type 2 diabetic patients who exhibit SU inefficacy has not yet been evaluated. In this preliminary study, fasting blood samples were collected from 16 Type 2 diabetic patients with secondary SU failure. As controls, 16 sex-, age- and adiposity-matched diabetic patients, who had similar diabetic duration and optimal glycemic control by SU, were also recruited. The results show that plasma values of leptin, C-peptide, calcium, magnesium, copper, and zinc did not significantly differ in these diabetic patients with or without secondary SU failure. However, the gender effect on plasma leptin level and the correlations between leptin and adiposity and C-peptide were retained. This study indicates that there is no relation between SU inefficacy and the plasma status of leptin and selected minerals.

Effect of zinc on cellular levels of calmodulin and cyclic adenosine monophosphate in the adipocyte

A perturbation of zinc metabolism has been noted in subjects with obesity. Zinc may also participate in the intracellular signal cascade by affecting cellular calcium influx and a change in the calcium-calmodulin (CaM)-cyclic adenosine monophosphate (cAMP) pathway. The possible effects of zinc on cellular concentrations of CaM, a major cytosolic calcium-binding protein, in the adipocytes derived from obese (ob/ob) mice and their lean counterparts were studied. Adipocytes derived from both phenotypes of mice were treated either with 0.2 mM of zinc sulfate or without any additive for 1 h of incubation; the cellular levels of CaM and cAMP were then determined. The results showed that the obese mice had lower CaM and cAMP levels in their adipocytes compared to the lean mice. Zinc treatment reduced CaM and increased cAMP levels in all mice, although this effect was more pronounced in the lean mice. This study indicated that there was an inverse interaction between CaM and cAMP in their cellular levels in the mouse adipocytes and that might be affected by exogenous zinc addition.

Molecular diagnosis of fragile X syndrome and distribution of CGG repeats in the FMR-1 gene in Taiwanese

BACKGROUND AND PURPOSE

Fragile X syndrome, the most frequent form of inherited mental retardation, is caused by abnormal expansion of the CGG trinucleotide repeats in the 5' untranslated region of the FMR-1 gene. In this study, we describe the prenatal diagnosis of fragile X syndrome and the distribution of CGG repeat numbers in the FMR-1 gene, which has not been previously reported in Taiwanese.

METHODS

Using polymerase chain reaction (PCR), we determined the range of the CGG repeats in the FMR-1 gene in 316 normal individuals (350 X chromosomes) and 349 mentally retarded patients (429 X chromosomes). For prenatal diagnosis of fragile X syndrome, DNA extracted from amniotic fluid cells was used for PCR determination of CGG repeats.

RESULTS

Because there were no significant differences between the distribution of the (CGG)n alleles between the mentally retarded and normal subjects, the data were pooled. Among the 779 X chromosomes studied, 24 different alleles were identified with a low of 16 and a high of 45 CGG repeats. The 29 repeat allele was the most common, followed by the 30 and the 28 repeat alleles. We effectively amplified slightly expanded premutation alleles of up to about 90 CGG repeats. In the prenatally diagnosed fetus, a normal 29 repeat allele was found.

CONCLUSIONS

Determination of the distribution of the CGG repeats in the FMR-1 gene in Taiwanese is useful in genetic counseling regarding fragile X syndrome. Prenatal molecular diagnosis of the syndrome can be successfully performed using amniotic fluid cells.

Imaging in the diagnosis and follow-up evaluation of vertebral artery dissection

The purpose of this report is to discuss the value of ultrasonographic examination in the diagnosis and follow-up evaluation of vertebral artery dissection. We collected data on 8 patients with 11 pathologic vessels: 9 were affected intracranially and 6 were affected extracranially. Four vessels were affected in both intracranial and extracranial segments. Extracranial color-flow duplex sonography could detect abnormalities in every extracranial vertebral artery dissection. Most abnormal findings were non-specific, including severely reduced flow, absence of flow, and absence of diastolic flow. A specific finding (intramural hematoma) was noted in one artery. Abnormal transcranial color-coded sonographic findings included absence of flow, reduced velocity and reversed flow direction. Three intracranial dissecting arteries showed normal findings on transcranial color-coded sonography. Ultrasonographic follow-up study revealed evidence of improvement; this was noted almost exclusively in the extracranial segments of the vertebral artery but infrequently in the intracranial segment. Extracranial color-flow duplex sonography is sensitive in the detection of extracranial vertebral artery dissection, both in initial diagnosis and in follow-up evaluation.

Carotid and transcranial color-coded duplex sonography in different types of carotid-cavernous fistula

BACKGROUND AND PURPOSE

Patients with carotid-cavernous fistula (CCF) may undergo direct or indirect shunting. Ultrasonography has value that is complementary to angiography in the assessment and follow-up of these patients. The aim of this study was to characterize findings provided by carotid duplex sonography (CDS) and transcranial color-coded duplex sonography (TCCD) in patients with different types of CCF.

METHODS

CDS and TCCD were independently performed by technologists and neurologists. Digital subtraction or MR angiography was interpreted by a neuroradiologist. Ultrasonographic studies were categorized into 4 types: I, direct shunting only; II, direct shunting with a carotid aneurysm; III, indirect shunting only; and IV, mixed (direct and indirect) shunting. In addition to carotid and intracranial flow velocities, volume, and pulsatility, other direct and indirect ultrasound signs of shunting were evaluated. The direct sign of CCF was a mosaic flash detected by TCCD. Alteration of hemodynamic parameters on CDS and demonstration of draining veins with the use of TCCD were considered indirect signs.

RESULTS

Fifteen patients (8 men, 7 women) were included in the study. According to angiographic results, patients in ultrasonographic classification types I (n=7) and II (n=3) corresponded to type A of Barrow's classification. Patients with type III (n=8) were Barrow's type C. Type IV (n=1) had a combination of Barrow's types A and C. On ultrasound, both direct and indirect signs were seen in types I, II, and IV CCF. The presence of a 2-colored oval mass divided by a zone of separation without turbulence differentiated type I from type II CCF. All patients with type III CCF had indirect signs, and only 1 patient had direct signs on TCCD. Abnormal TCCD findings were most commonly seen through the transorbital window (100%), followed by the transtemporal window (63%) and transforaminal window (40%).

CONCLUSIONS

If only indirect ultrasonographic signs of CCF are present, TCCD can be used to predict an indirect CCF type on the basis of the origin of the fistula. With direct communication between carotid artery and cavernous sinus, both direct and indirect ultrasonographic signs can be found. The combination of CDS/TCCD may provide a noninvasive and reliable way to classify patients with CCF.

Leptin concentration and the Zn/Cu ratio in plasma in women with thyroid disorder

We investigated the possible correlation between the leptin concentration and the Zn/Cu ratio in the plasma of women with thyroid disorder. Forty women with hypothyroidism (n = 20) or hypothyroidism (n = 20) and 20 euthyroid controls were recruited. The results showed that the women with thyroid disorder (hypothyroidism or hyperthyroidism) had higher plasma leptin concentrations than the normal controls (p < 0.05). Moreover, the plasma leptin concentration had no correlation with plasma thyroid hormone levels in the separate groups, nor among all the participants considered together. A strong correlation (p < 0.005) between leptin and adiposity was only observed in euthyroid women. Plasma values of Zn and Cu and the Zn/Cu ratio were not markedly different among women with altered thyroid status. However, a weak correlation (r = 0.28, p = 0.032) between leptin and the Zn/Cu ratio was found from the pooled data of all participants and retained after adjustment for adiposity. We suggest that there may exist an interaction between the plasma leptin level and thyroid hormone-induced abnormality for selected minerals.

Aetiologies and prognosis of Chinese patients with deep vein thrombosis of the lower extremities

Deep vein thrombosis (DVT) of the lower extremities is not frequently encountered in Oriental patients. We investigated its aetiology and prognosis in 143 patients (65 males, 78 females), presenting to the National Taiwan University Hospital over 4.3 years, diagnosed by colour Doppler ultrasonography. Swelling and pain of the lower extremities were the most frequent presenting symptoms. The left femoropopliteal veins were more frequently involved than other parts of the lower extremities. In these patients, malignancy with or without intravenous catheterization was the most frequent cause (39 patients, 27%). Other common aetiologies included coagulopathy (29 patients, 20%), immobilization (24 patients, 17%) and catheter-related (13 patients, 9%). No definite aetiology could be determined in 37 patients (26%). During follow-up, 27 patients (19%) died, mostly with malignancy. Pulmonary embolism was noted in 16 patients and was not significantly directly related to death. Compared to similar studies in Caucasian patients, there were significant differences in the aetiology of DVT, with malignancy and coagulopathy more common in these Chinese patients.

Effects of zinc supplementation on the plasma glucose level and insulin activity in genetically obese (ob/ob) mice

The effects of zinc supplementation (20 mM ZnCl2 from the drinking water for eight weeks) on plasma glucose and insulin levels, as well as its in vitro effect on lipogenesis and lipolysis in adipocytes were studied in genetically obese (ob/ob) mice and their lean controls (+/?). Zinc supplementation reduced the fasting plasma glucose levels in both obese and lean mice by 21 and 25%, respectively (p < 0.05). Fasting plasma insulin levels were significantly decreased by 42% in obese mice after zinc treatment. In obese mice, zinc supplementation also attenuated the glycemic response by 34% after the glucose load. The insulin-like effect of zinc on lipogenesis in adipocytes was significantly increased by 80% in lean mice. However, the increment of 74% on lipogenesis in obese mice was observed only when the zinc plus insulin treatment was given. This study reveals that zinc supplementation alleviated the hyperglycemia of ob/ob mice, which may be related to its effect on the enhancement of insulin activity.

Zinc supplementation on serum levels and hepatic conversion of thyroid hormones in obese (ob/ob) mice

The supplemental effects of zinc on thyroid status in obese (ob/ob) mice were studied. Four-week-old obese mice and their lean controls were fed either a basal diet or a zinc-supplemented diet (200 mg/kg diet) for 8 wk. Following the 8-wk basal diet, obese mice had lower serum T4 values, as well as hepatic T4 and T3 values, than lean mice (p < 0.05). A significant decrease in hepatic 5'-deiodinase activity was also observed in obese mice. Dietary zinc supplementation significantly reduced serum T4 levels in both the obese and lean mice. However, the zinc-supplemented effects on diminishing hepatic T4 and T3 values, as well as on 5'-deiodinase activities, were found only in obese mice (p < 0.05). Furthermore, the 5'-deiodinase activities in hepatic microsomal pellets after incubation with various zinc concentrations (0.5, 1.0, and 2.5 mM) were also examined. The 5'-deiodinase activities, in hepatic samples from all mice, were significantly attenuated by zinc treatments. However, this effect was more predominant in obese mice following the addition of 0.5 mM zinc. This study suggests that a lower hepatic 5'-deiodinase activity, resulting from a higher zinc level, might be related to abnormal energy metabolism in the ob/ob mice.

[The lymphoepithelial lesion in salivary glands:report of 25 cases]

This paper reported the results of the clinical observation and long-term follow-up of twenty-five cases of lymphoepithelial lesion in salivary glands.It evaluated the name and character of this disease and investigated correlation between Mikulicz syndrome and Sjogren syndrome.Lymphoepithelial lesion were a course of the benign disease,and had character similar as tumors.It was liable to be diagnosed erroneously and should be treated according to principle of the tumor therapy in the salivary gland.

Dimerization of the N-terminal amphipathic alpha-helix domain of the fungal immunomodulatory protein from Ganoderma tsugae (Fip-gts) defined by a yeast two-hybrid system and site-directed mutagenesis

A fungal immunomodulatory protein (Fip-gts) was purified from Ganoderma tsugae. The DNA encoding Fip-gts was isolated from a cDNA library of G. tsugae by reverse transcriptase-polymerase chain reaction. The complete amino acid sequence of Fip-gts, deduced from the nucleotide sequence of the cDNA, was the same as LZ-8 isolated from Ganodermn lucidum. Recombinant Fip-gts was expressed as a glutathione S-transferase fusion protein in Escherichia coli with a yield of 20 mg/liter of culture. Recombinant Fip-gts, purified to homogeneity, had the same blast formation stimulatory activity to human peripheral blood lymphocytes as native Fip-gts. The yeast two-hybrid system and site-directed mutagenesis were used to determine whether dimerization of Fip-gts occurred. Deletion analysis of the N-terminal amphipathic alpha-helix domain of Fip-gts identified a sequence of about 10 amino acids responsible for inducing immunomodulatory activity. Non-functional Fip-gts deletion mutants did not form dimers, whereas wild type Fip-gts did as determined by gel filtration. A mutant with deletions at Leu-5, Phe-7, and Leu-9 lost the amphipathic characteristics of the N-terminal domain and the ability to form dimers as well as its immunomodulatory activity. Fusion of Fip-gts with the DNA binding and the transactivation domains of GAL4 resulted in the activation of the lacZ activator gene, indicating the interaction of Fip-gts with it itself. The dimerization domain was further defined by analyzing the ability of the N-terminal 13 amino acids or Leu-5, Phe-7, and Leu-9 deletion mutants of Fip-gts to interact with the wild type Fip-gts. These experiments confirmed the N-terminal amphipathic alpha-helix as the dimerization domain and suggest that the dimerization of Fip-gts may play an important role in Fip-gts immunomodulatory activity.

Zinc attenuation of GDP binding to brown adipocytes mitochondria in genetically obese (ob/ob) mice

In this study, we investigate the in vitro effect of zinc addition on guanosine diphosphate (GDP) binding to mitochondria in brown adipocytes of genetically obese (ob/ob) mice. Interscapular brown adipocytes of male mice (obese; lean) at 4 and 12 wk of age were incubated with 0, 50, 100, or 200 microM zinc sulfate. Mitochondria were then isolated and their GDP binding capacities were measured. The GDP-binding capacities of ob/ob mice were lower than lean mice, with or without zinc addition, in both age groups (p < 0.05). Zinc addition did not have any significant effect on GDP binding in lean mice. GDP binding decreased with increasing zinc addition in ob/ob mice, and this attenuation was more predominant in 12-wk old ob/ob mice. Moreover, we found that high magnesium addition (5 mM) increased GDP binding in lean mice, but this effect was not significant in ob/ob mice. This study reveals that brown adipose tissue thermogenesis in ob/ob mice could be greatly attenuated by zinc addition, suggesting that zinc may play a regulatory role in obesity.

A diether phosphonolipid surfactant analog, DEPN-8, is resistant to phospholipase-C cleavage

Increased activities of phospholipase A2 and C (PLC) have been observed in the bronchoalveolar lavages of patients with adult respiratory distress syndrome (ARDS). DL-alpha-Di-O-hexadecylphosphonocholine [(R)(S)-DEPN-8], a surfactant analog of superior surface activity to the major lung surfactant phospholipid, dipalmitoylphosphatidylcholine (DPPC), is not a substrate for phospholipases A1, A2 and D, but is a substrate for PLC. (R)(S)-DEPN-8 was found in vitro to undergo significantly less PLC-catalyzed degradation as compared to DPPC. The results suggest that (R)(S)-DEPN-8 and structurally related analogs may be useful as components of exogenous replacement surfactant formulations for the treatment of ARDS-related lung injuries.

Ultrasonographic study and long-term follow-up of Takayasu's arteritis

BACKGROUND AND PURPOSE

Takayasu's arteritis is an inflammatory vasculopathy involving the aorta and its major branches. Little information is available on the natural history and temporal profile of changes in the carotid vessels, the major vessels involved in Takayasu's arteritis. Duplex ultrasonography may provide a reliable and efficient tool for the characterization and follow-up of the brachiocephalic vascular changes in Takayasu's arteritis.

METHODS

Sixteen female patients fulfilling the clinical diagnostic criteria for Takayasu's arteritis were studied. Mean age at onset was 23.6 years (SD = 6.0), and mean duration of follow-up was 17.1 years (SD = 11.9). The clinical features were analyzed. Only one patient had had a stroke. They had undergone at least one duplex scanning examination to evaluate the brachiocephalic vessels, including the extracranial carotid, vertebral, and subclavian arteries. Six patients underwent sequential duplex examination and long-term clinical follow-up.

RESULTS

All the studied patients had subclavian artery involvement, and 11 (69%) had common carotid artery involvement. The percentage of bilateral concomitant involvement was 100% in the common carotid artery and 33% in the subclavian artery. Homogeneous circumferential intima-media thickening was commonly seen in stenotic common carotid arteries (89%). Four patients had internal carotid artery involvement (all on the left side). In the serial duplex follow-up study, 2 of 6 patients had progressive vascular stenosis with concentric thickening, rather than longitudinal spreading, in the bilateral common carotid arteries. Left-side lesions were more prominent. Most were clinically stationary, despite severe stenosis or occlusion of the common carotid arteries.

CONCLUSIONS

The characteristic vascular lesions and progression changes in Takayasu's arteritis detected by duplex ultrasonography are quite different from those seen in ordinary atherosclerosis. Homogeneous circumferential intima-media thickening of the common carotid arteries is a highly specific ultrasonographic finding in patients with Takayasu's arteritis, particularly young women. Sequential duplex scanning showed vascular progression to be unpredictable and unrelated to medication in our patients. Further clinical investigations of vascular progression are warranted, and duplex scanning may provide a simple, safe, and accurate long-term means of follow-up.

Prenatal diagnosis in a Chinese family with type Ia glycogen storage disease by PCR-based genetic analysis

Type Ia glycogen storage disease (GSD), an autosomal recessive metabolic disorder, is caused by a deficiency in glucose-6-phosphatase (G6Pase). We had previously identified the nature of the causative mutations in a Chinese family whose first two children were affected with type Ia GSD. Two different point mutations in the G6Pase gene, a guanine to adenine substitution at base position 327 in exon 2 and a thymine to adenine substitution at base position 1101 in exon 5, change the restriction sites for the enzymes Fok I and Hinc II. Family study revealed that both parents were heterozygous carriers: the father with a mutant G6Pase allele at exon 2 and the mother with another mutant G6Pase allele at exon 5. This paper deals with a prenatal diagnosis on the fetus of this family who is at risk of type Ia GSD. Genomic DNA was extracted from a chorionic villus biopsy sampled at the tenth week of gestation. Exons 2 and 5 of the G6Pase gene were amplified by the polymerase chain reaction (PCR) followed by restriction enzyme digestion and direct sequence analysis. DNA analysis indicated that the fetus was a heterozygous carrier of type Ia GSD with a mutant G6Pase allele at exon 2 and a normal G6Pase allele at exon 5. The diagnosis was further confirmed by the same method with cultured amniocytes and with a blood sample after the baby was born. This is the first report of prenatal carrier detection of type Ia GSD at the gene level.

Neoplastic response in Japanese medaka and channel catfish exposed to N-methyl-N'-nitro-N-nitrosoguanidine

Japanese medaka (Oryzias latipes) and channel catfish (Ictalurus punctatus) were investigated for carcinogenic response following a 28-day, 3 x/wk pulse exposure to N-methyl-N'-nitro-N-nitrosoguanidine (MNNG). Five-wk-old medaka were exposed at concentrations of 0, 0.5, and 1.0 mg/L, and 5-mo-old catfish at concentrations of 0, 0.1, and 0.5 mg/L. In medaka, a total of 19 tumors including 2 branchioblastomas, 6 thyroid follicular adenomas and 1 adenocarcinoma, and 11 subcutaneous fibrosarcomas were observed in 16 of 96 MNNG-exposed fish. In catfish, a total of 37 tumors including 4 squamous cell carcinomas and 16 papillomas, 3 lipomas, 1 fibroma, 1 osteosarcoma, 4 branchioblastomas, 6 thymic epithelial tumors, and 2 generalized lymphosarcomas were observed in 34 of 172 MNNG-exposed fish. The induction of neoplasms in medaka was primarily in the gill, thyroid, and subcutis of the cervical and trunk regions, whereas in catfish skin, thymus, oro-pharynx, and hemopoietic tissues were also commonly affected. In both species, the neoplastic response was considered to be related to direct exposure of the tissues to MNNG. Some of these tumors have not been reported in the literature in either natural or experimental fish. The results also suggest species-specific differences in carcinogenic response following MNNG exposure.

Genetic analysis of the glucose-6-phosphatase mutation of type 1a glycogen storage disease in a Chinese family

Type 1a glycogen storage disease (GSD) is an autosomal recessive metabolic disorder caused by a deficiency in glucose-6-phosphatase (G6Pase). Polymerase chain reaction (PCR) and nucleotide sequence analysis were used to identify the location and nature of mutations at the G6Pase locus in two siblings affected with type 1a GSD. Both patients are compound heterozygotes with two different single nucleotide substitutions in the two G6Pase alleles. A guanine to adenine transition was identified at base position 327 in the exon 2, converting an arginine to a histidine at codon 83. The second substitution was a thymine to adenine transversion at base position 1101 in the exon 5, converting an isoleucine to an asparagine at codon 341. Family study reveals that both parents are heterozygous carriers: the father with a mutant G6Pase allele at exon 2, the mother with another mutant G6Pase allele at exon 5. This is the first family study in Taiwan on type 1a GSD identified by molecular analysis. The mutations identified herein are novel substitutions in the G6Pase gene. In addition, an adenine to guanine substitution was observed at base position 653 in the exon 5 of G6Pase gene in both sibling patients and their parents, as well as in 15 normal Chinese subjects and three normal Caucasian subjects.

Reverse jugular flow in a case of thrombosis of the brachiocephalic vein with an artificial arteriovenous fistula

Thrombosis of the thoracic inlet veins following placement of a central venous catheter is a well-known complication, and several findings have been reported by color Doppler sonography. However, reverse jugular flow resulting from this complication is rarely mentioned and should be differentiated from another complication of iatrogenic arteriovenous fistula between neck vessels. The authors here describe a uremic patient with an artificial arteriovenous fistula in the forearm complicated with thrombosis of the ipsilateral brachiocephalic vein. Factors permitting the differential diagnosis by coloer Doppler sonography and clinical conditions are proposed.

Zinc supplementation aggravates body fat accumulation in genetically obese mice and dietary-obese mice

A perturbation of zinc metabolism has been noted in numerous laboratory animals with diabetes and obesity. The effects of zinc supplementation on body fat deposition in two types of experimental obese mice: genetically obese (ob/ob) mice and high-fat diet-induced ICR obese (HF) mice were investigated in this study. Their lean controls were +/? mice, and ICR on basal diet, respectively. The mice in the zinc-supplemented groups were administered 200 mg/kg zinc in their diets for 6 wk. Both the ob/ob mice and the HF mice, that were fed a diet containing a marginal zinc dosage (4-6 mg/kg), had lower zinc levels in their serum and carcass, and higher body fat content than their respective lean controls (p < 0.01). After zinc supplementation, ob/ob mice and the HF mice significantly (p < 0.05) increased their body fat by 49.4% and 18.9%, respectively. This study revealed that body fat deposition can be aggravated by zinc supplementation in both types of obese mice. Zinc may be associated with the energy homeostasis of obesity, via its interaction with dietary fat consumption.

Restoration of lung compliance with calf lung surfactant extract and a surfactant analog in an in situ model of surfactant deficiency in rats

We have developed a standardized in situ lung surfactant deficiency model in the rat by using a single bronchoalveolar lavage (BAL). The purpose of this study was to assess the usefulness of surfactants and surfactant analogs in terms of their in vivo physiological properties. Calf lung surfactant extract (CLSE) was shown to improve lung compliance in a dose-dependent manner in this surfactant deficiency model when administered intratracheally immediately after BAL. In addition, CLSE formulated with a diether (palmityl) phosphonolipid surfactant analog significantly improved the compliance post-BAL as compared to CLSE alone. We propose that this in situ bioassay may be useful for the assessment of physiological capabilities of surfactants, surfactant analogs and surfactant formulations.

Diagnosis and follow-up of carotid-cavernous fistulas by carotid duplex sonography and transcranial color Doppler imaging

To investigate the suitability of extracranial carotid duplex (ECD) and transcranial color Doppler imaging (TCDI) in the diagnosis and follow-up of treatment in patients with carotid-cavernous fistulas (CCF), combined ECD and TCDI examinations were studied in seven patients with traumatic CCF. According to angiography, four patients had direct CCF, two indirect CCF and one both direct and indirect CCF. In ECD, hemodynamic parameters of the feeding artery showed an abnormally increased flow volume and decreased resistivity indices in five direct CCFs from the internal carotid artery and one indirect CCF from the external carotid artery. Direct visualization of the CCF was achieved in patients with direct CCF only, and revealed itself as a heterogeneous mosaic flash resulting from high flow velocities and turbulence. Patterns of venous drainage were detected via the transorbital and transforaminal windows in seven and five patients (four direct and one indirect CCF patients), respectively. These abnormal findings were improved or even normalized after successful treatment. In conclusion, combined ECD and TCDI examinations appear to be useful for the diagnosis and follow-up of CCF.

Genetic analysis of the HPRT mutation of Lesch-Nyhan syndrome in a Chinese family

BACKGROUND

The Lesch-Nyhan syndrome is an X-linked recessive inherited disease caused by a complete deficiency of hypoxanthine guanine phosphoribosyl-transferase (HPRT) activity. Many different mutations throughout the HPRT coding region of Lesch-Nyhan patients have been described, including single base substitutions, partial or entire gene deletions, gene insertions or endoduplication of exons. However, study of gene mutation in Chinese patients has rarely been reported in Taiwan.

METHODS

Polymerase chain reaction (PCR) and nucleotide sequence analysis were used to identify the location and the nature of the mutation at the HPRT locus in two brothers affected with Lesch-Nyhan syndrome. The HPRT cDNA, amplified from total RNA of patient's peripheral blood by reverse transcription-polymerase chain reaction, was cloned into a pGEM-3Zf(-) vector and then sequenced. Family study involved initial screening using single-strand conformation polymorphism, and further confirmation by direct sequencing of the exon encompassing the mutation.

RESULTS

The mutation identified in these two affected siblings was a single nucleotide substitution, from cytosine to guanine, in exon 3 of the HPRT coding region. This transversion putatively caused a single amino acid substitution from phenylalanine to leucine at codon 74 in the translated protein. This base change was further confirmed by direct sequencing of both the HPRT cDNA fragment and the exon 3 of HPRT gene amplified from genomic DNA. The family study revealed that the patient's mother was a heterozygous carrier, and the mutation seemed to have occurred de novo in a germinal cell from one of the maternal grandparents.

CONCLUSIONS

This is the first family study on Chinese patients with Lesch-Nyhan syndrome identified by molecular analysis in Taiwan. The mutation described herein is a novel substitution which occurs in a suggested "hotspot" of mutation (exon 3) of the HPRT gene. The application of molecular analysis of HPRT-gene allows not only DNA diagnosis by directly detecting the mutant alleles, but also prenatal diagnosis and carrier identification within individual families affected by Lesch-Nyhan syndrome.

Dietary copper supplementation increases the catecholamine levels in genetically obese (ob/ob) mice

The interactive relationship between Cu deficiency and depressed synthesis of certain neurotransmitters has been recognized. To investigate the effects of dietary Cu supplementation on the catecholamine levels in genetically obese mice, male obese (ob/ob) mice and their lean (+/?) counterparts were administered either a control diet (4.0 mg/kg) or a Cu-supplemented diet (50 mg/kg) for 4 wk. The ob/ob mice that were fed a control diet showed lower liver and higher plasma levels of Cu. Depressed levels of plasma and brain catecholamines were also found in ob/ob mice that were fed the control diet. The ob/ob mice that received a Cu-supplemented diet showed significant increases in the levels of catecholamine in the plasma and brain. This study showed that catecholamine levels in ob/ob mice can be increased by dietary Cu supplementation. However, the interaction between Cu and sympathetic nervous activity in obesity was not elucidated in this study.

Selected metals status in patients with noninsulin-dependent diabetes mellitus

In order to investigate the relationships between metals zinc [Zn], copper [Cu], magnesium [Mg], or Calcium [Ca] and noninsulin-dependent diabetes mellitus, 65 patients of newly diagnosed noninsulin-dependent diabetes mellitus and 54 nondiabetic healthy controls were studied. The concentrations of selected metals in fasting blood samples and 24-h urine collections were determined. Hyperzincuria and hypermagnesuria were detected in diabetic patients (p < 0.01). The diabetics also had lower Zn and Mg, and higher Cu, and Ca levels in their plasma than those of the controls, but the statistical differences in Ca and Mg were not significant. Significantly lower Zn and higher Ca levels in erythrocytes were found in diabetic patients (p < 0.01). There is evidence of a significant difference in metals status between diabetic patients with or without the specific complications. This study further indicates that patients with NIDDM on Taiwan also have distinct changes in their metals status, and these perturbations are associated with some diabetic complications.

Expression of a Drosophila GATA transcription factor in multiple tissues in the developing embryos. Identification of homozygous lethal mutants with P-element insertion at the promoter region

GATA transcription factors are DNA-binding proteins that recognize the core consensus sequence, WGATAR. Previous studies indicated that GATA factors play ann important role in the development of tissue-specific functions in vertebrates. Here we report the identification of a new Drosophila melanogaster GATA factor, dGATAc, which displays a distinct expression pattern in embryos. The local concentration of dGATAc transcripts varies at different stages, being most prominent in the procephalic region at stages 6-10 and in the posterior spiracles, the gut, and the central nervous system at stages 11-13. On the basis of its predicted sequence, DNA-binding assays were performed to confirm that the dGATAc gene encodes a zinc finger protein that can bind the GATA consensus motif with predicted specificity. Two independent mutants carrying a P-element insertion at the dGATAc gene promoter region were identified that are homozygous lethal at the embryonic stage. Using a genetic scheme, it was demonstrated that the lack of dGATAc function can block normal embryonic development. Our results suggest that the dGATAc protein is a tissue-specific transcription factor that is vital to the development of multiple organ systems in D. melanogaster.

In vivo function of surfactants containing phosphatidylcholine analogs

Increased phospholipase A2 activity demonstrated in some forms of lung injury may contribute to surfactant dysfunction. Phospholipase A2-resistant analogs of dipalmitoylphosphatidylcholine (DPPC) with surfactant properties might therefore be useful lipid components of treatment surfactants for certain lung injuries. The in vivo function of surfactants containing DPPC or the phospholipase-resistant analogs dihexadecylphosphatidylcholine (DEPC) or dihexadecylphosphonotidylcholine (DEPnC), with or without surfactant proteins B and C (SP-B+C), was thus evaluated in preterm rabbits (27 days' gestation). Rabbits randomly received one of seven surfactants (DPPC, DEPC, DEPnC, DPPC+SP-B+C, DEPC+SP-B+C, DEPnC+SP-B+C, or lipid extract surfactant [LES]) or 0.45% NaCl (control) and were ventilated for 30 min. Lipid-only surfactants decreased ventilatory pressures (peak inspiratory pressures minus positive end-expiratory pressure) relative to control (p < 0.05). Addition of SP-B+C further decreased ventilatory pressures to levels similar to LES (p < 0.01 versus control, lipid-only surfactants). Lung dynamic compliances and postventilation pressure-volume curves improved in the following order: LES, SP-B+C lipid surfactants > lipid-only surfactants > control (p < 0.05). All surfactant preparations decreased intravascular 125I-albumin recoveries in the lungs relative to control (p < 0.01 for all surfactants versus control). These results indicate that DEPC and DEPnC were as effective as DPPC as lipid components of synthetic surfactants. And like DPPC, the analogs interacted with isolated SP-B+C and improved in vivo function to levels comparable to LES.