Sensitive high-performance liquid chromatographic determination with fluorescence detection of phenol and chlorophenols with 4-(4,5-diphenyl-1H-imidazol-2-yl)benzoyl chloride as a labeling reagent

A sensitive HPLC method for the determination of phenol and chlorophenols was developed. The fluorescence labeling reaction of phenols with 4-(4,5-diphenyl-1H-imidazol-2-yl)benzoyl chloride (DIB-Cl) was completed in 30 min at 60 degrees C. The separation of DIB-derivatives of five representative phenols, i.e., phenol, o-, p-chlorophenol, 2,4-dichlorophenol, 2,4,6-trichlorophenol, was achieved within 35 min with an ODS column using isocratic elution. The detection limits of these DIB derivatives at a signal-to-noise ratio (SIN) of 3 were in the range of 0.024 to 0.08 microM (0.12-0.45 pmol/20 microl injection). Twelve kinds of DIB derivatives with phenols containing mono-, di-, tri-, tetra- and penta-chlorophenol were also well separated within 208 min by changing the elution conditions. The derivatives were stable for at least for 24 h when they were placed at room temperature in the dark. The proposed method was applied to the assay of human urine samples and free and total phenol were determined. The relative standard deviations (RSDs) of the proposed method for within and between-day assay were <7.0% and <14.2%, respectively. The average concentrations of free and total phenol found in urine (n=6) were 4.3+/-2.5 and 29.5+/-14.0 microM, respectively.

A comparison of tau protein in cerebrospinal fluid between corticobasal degeneration and progressive supranuclear palsy

Many clinical and pathological discussions have been focused on the difficulty of differential diagnosis between corticobasal degeneration (CBD) and progressive supranuclear palsy (PSP) in recent years. This study was conducted to evaluate the usefulness of tau proteins in cerebrospinal fluid (CSF) for the differentiation of these two diseases. Subjects consisted of 10 patients with CBD (four males and six females with a mean age of 67.9+/-5.8 years), 12 patients with PSP (eight males and four females with a mean age of 62.6+/-5.8 years) and 36 control subjects (CTL) (16 males and 20 females with a mean age of 65.8+/-9.9 years). The CBD group included patients with probable CBD, while all the patients in the PSP group satisfied the diagnostic criteria developed by the National Institute of Neurological Disorders and Stroke and Society for PSP (NINDS-SPSP). CSF tau proteins were measured with the sandwich ELISA method (Innogenetics, Belgium). The CSF tau protein level was 320.1+/-86.5 pg/ml in the CBD group, 151.5+/-52.7 pg/ml in the PSP group and 128.7+/-91.7 pg/ml in the CTL group. Significant differences were noted in tau protein levels between the CBD group and both the PSP group (P<0.001) and the CTL group (P<0.005). We suggested that the measurement of CSF tau proteins may be useful for the differentiation between CBD and PSP.

Calcium binding induces interaction between the N- and C-terminal domains of yeast calmodulin and modulates its overall conformation

Calmodulin from the yeast Saccharomyces cerevisiae binds 3 mol of Ca2+ cooperatively. We report here lines of evidence supporting the intramolecular interaction between the N- and C-terminal domains which modulates the Ca2+ binding properties of yeast calmodulin. First, the sum of the Ca2+ binding curves of the N-terminal and the C-terminal half-molecule did not yield the Ca2+ binding curve of yeast calmodulin. Second, the mean residue CD of yeast calmodulin at 222 nm (-Delta epsilon222) decreased with increases in the concentration of Ca2+, whereas those of each half-molecule increased. Finally, the C2 proton of His107 in the C-terminal domain of yeast calmodulin showed three resonance peaks with increases in the concentration of Ca2+, each corresponding to the apo, the intermediate, and the Ca2+-saturated state. The intermediate peak could not be observed in the C-terminal half-molecule of yeast calmodulin. Computer simulation considering the macroscopic Ca2+ binding constants assigned this intermediate to a species consisting of the apo C-terminal domain and the N-terminal domain with at least one of the two sites occupied by Ca2+. Peptide segments spanning the defective fourth Ca2+ binding site may be involved in the interdomain interaction and the yeast-specific function of calmodulin.

A strange calmodulin of yeast

Calmodulin of Saccharomyces cerevisiae has different Ca2+ binding properties from other calmodulins. We previously reported that the maximum number of Ca2+ binding was 3 mol/mol and the fourth binding site was defective, which was different from 4 mol/mol for others. Their macroscopic dissociation constants suggested the cooperative three Ca2+ bindings rather than a pair of cooperative two Ca2+ bindings of ordinary calmodulin. Here we present evidence for yeast calmodulin showing the intramolecular close interaction between the N-terminal half domain and the C-terminal half domain, while the two domains of ordinary calmodulin are independent of each other. We will discuss the relationship of the shape and the shape change caused by the Ca2+ binding to the enzyme activation in yeast. The functional feature of calmodulin in yeast will also be considered, which might be different from the one of vertebrate calmodulin.

Rapid molecular genetic subtyping of serotype M1 group A Streptococcus strains

Serotype M1 group A Streptococcus, the most common cause of invasive disease in many case series, generally have resisted extensive molecular subtyping by standard techniques (e.g., multilocus enzyme electrophoresis, pulsed-field gel electrophoresis). We used automated sequencing of the sic gene encoding streptococcal inhibitor of complement and of a region of the chromosome with direct repeat sequences to unambiguously differentiate 30 M1 isolates recovered from 28 patients in Texas with invasive disease episodes temporally clustered and thought to represent an outbreak. Sequencing of the emm gene was less useful for M1 strain differentiation, and restriction fragment length polymorphism analysis with IS1548 or IS1562 as Southern hybridization probes did not provide epidemiologically useful subtyping information. Sequence polymorphism in the direct repeat region of the chromosome and IS1548 profiling data support the hypothesis that M1 organisms have two main evolutionary lineages marked by the presence or absence of the speA2 allele encoding streptococcal pyrogenic exotoxin A2.

Effects of thyroid hormones on myofibrillar proteolysis and activities of calpain, proteasome, and cathepsin in primary cultured chick muscle cells

The effects of thyroxine (T4) and triiodothyronine (T3) on growth, muscle protein degradation, and proteases activities in cultured chick muscle cells were studied. The cells were treated with a physiological level of T4 (60 ng/mL) or T3 (12 ng/mL) for 6 d. Calpain, cathepsins, and proteasome activities and N tau-methylhistidine release were measured as indexes of myofibrillar protein breakdown. Creatine kinase activity was also measured as an index of myotube formation. Calpain activity was increased by T4 and T3. Cathepsin D and proteasome activities and N tau-methylhistidine release were increased by T3, but not by T4. Neither were cathepsin B and B + L activities affected by T3 or T4. Creatine kinase activity was increased by T4 and T3. The results suggest that myotube formation is accelerated by T4 and T3, whereas myofibrillar protein degradation is accelerated by T3, but not by T4.

Preparation and evaluation of new Pirkle type chiral stationary phases with long alkyl chains for the separation of amino acid enantiomers derivatized with NBD-F

In order to improve the high-performance liquid chromatographic separation of alpha-amino acids derivatized with the fluorogenic reagent 4-fluoro-7-nitro-2,1,3-benzoxadiazole (NBD-F) on commercially available chiral stationary phases (CSPs) such as SUMICHIRAL OA-2500(S) (CSP 1) and OA-4700 (CSP 3), the preparation of two new CSPs (CSP 2 and CSP 4) having 11-aminoundecanoic acid between the aminopropyl silica gel support and the chiral moiety in CSP 1 and CSP 3 is described. CSP 2 and CSP 4 improved both the mutual and enantiomeric separation of NBD-amino acids compared with CSP 1 and CSP 3. Thus, 17 pairs of NBD-amino acid enantiomers and NBD-glycine were separated on CSP 2 except for six NBD-amino acids (D-Asn, D-Ser, D-Gln, L-Pro, L-Ser and Gly). CSP 2 and CSP 4 also showed better enantiomeric separation of NBD-amino acid esters and amides than CSP 1 and CSP 3. It was considered that the achiral long alkyl chains in the CSPs might form a hydrophobic space which assisted the stereoselective interaction of analytes with the chiral moiety by changing the environment around the chiral moiety. On CSP 1 and CSP 2, NBD-beta-amino acid was also enantiomerically separated.

A gene encoding proline dehydrogenase is not only induced by proline and hypoosmolarity, but is also developmentally regulated in the reproductive organs of Arabidopsis

The cDNA clone ERD5 (early responsive to dehydration), isolated from 1-h-dehydrated Arabidopsis, encodes a precursor of proline (Pro) dehydrogenase (ProDH), which is a mitochondrial enzyme involved in the first step of the conversion of Pro to glutamic acid. The transcript of the erd5 (ProDH) gene was undetectable when plants were dehydrated, but large amounts of transcript accumulated when plants were subsequently rehydrated. Accumulation of the transcript was also observed in plants that had been incubated under hypoosmotic conditions in media that contained L- or D-Pro. We isolated a 1.4-kb DNA fragment of the putative promoter region of the ProDH gene. The beta-glucuronidase (GUS) reporter gene driven by the 1.4-kb ProDH promoter was induced not only by rehydration but also by hypoosmolarity and L- and D-Pro at significant levels in transgenic Arabidopsis plants. The promoter of the ProDH gene directs strong GUS activity in reproductive organs such as pollen and pistils and in the seeds of the transgenic plants. GUS activity was detected in vegetative tissues such as veins of leaves and root tips when the transgenic plants were exposed to hypoosmolarity and Pro solutions. GUS activity increased during germination of the transgenic plants under hypoosmolarity. The relationship between Pro metabolism and the physiological aspects of stress response and development are discussed.

[A case of intrathoracic lipoma arising from the chest wall resected by video-assisted thoracoscopic surgery]

We present a case of lipoma arising from the chest wall spreading into the thoracic cavity. Although asymptomatic, a 65-year-old female was pointed out an abnormal shadow on the chest X-ray film taken at the mass survey. The tumor, measuring 3.4 x 3.0 x 2.0 cm in diameter, was surgically removed under thoracoscopic visualization through a small thoracotomy incision of lt. 1st intercostal space, and the diagnosis of lipoma was confirmed postoperatively by histopathologic examination.

Motor and learning dysfunction during postnatal development in mice defective in dopamine neuronal transmission

Mice lacking expression of tyrosine hydroxylase (TH), the first and rate-limiting enzyme of the catecholamine biosynthetic pathway, in dopaminergic neuronal cell types were generated by a transgenic rescue approach to clarify the role of dopamine signaling during postnatal development. Introduction of the TH transgene directed by the dopamine beta-hydroxylase gene promoter into TH knockout mice restored noradrenaline and adrenaline synthesis, preventing perinatal lethality and cardiac dysfunction in the knockout mice. Lack of TH expression in the cells that normally express the dopaminergic phenotype resulted in a marked reduction of dopamine accumulation in the tissues, which led to multiple behavioral abnormalities at the juvenile stage. These abnormalities were characterized by a reduction in spontaneous locomotor activity, blockade of methamphetamine-induced hyperactivity, cataleptic behavior, and defects in active avoidance learning. In contrast, development of the pituitary gland as well as production and secretion of the pituitary peptide hormones dependent on hypothalamic dopaminergic control were normally maintained, despite defective dopamine synthesis. These results demonstrate that dopamine neurotransmission is essential for controlling spontaneous and voluntary movement and associative learning during postnatal development through the nigrostriatal and mesocorticolimbic pathways.

HPLC with fluorescence detection of urinary phenol, cresols and xylenols using 4-(4,5-diphenyl-1H-imidazol-2-yl)benzoyl chloride as a fluorescence labeling reagent

A simple and sensitive HPLC method for the determination of phenolic compounds, i.e., phenol (Phe), cresols (Cres) and xylenols (Xyls), was developed. After a pre-column fluorescence derivatization of these compounds with 4-(4,5-diphenyl-1H-imidazol-2-yl)benzoyl chloride (DIB-Cl) at 60 degrees C for 30 min, 11 DIB derivatives were successfully separated within 50 min with an ODS column using CH3CN-H2O-CH3OH (25 + 22 + 53, v/v) as the eluent. The detection limits of DIB derivatives at a signal-to-noise ratio of 3 ranged from 0.15 to 1.09 microM (0.2-1.6 pmol per 20 microliters). The precision of the proposed method for both within- and between-day assays of free and total phenol related compounds was satisfactory (RSD < 9.5%). By the proposed method, Phe and p-Cre could be detected in normal urine samples, and the calculated concentrations of free Phe and p-Cre in unhydrolysed urine samples were 1.5 +/- 1.3 and 23.9 +/- 24.3 microM and those of total Phe and p-Cre in hydrolysed urine samples were 87.3 +/- 81.2 and 200.7 +/- 195.4 microM (n = 21), respectively.

Enantioselective high-performance liquid chromatography with fluorescence detection of methamphetamine and its metabolites in human urine

A simple, rapid and highly sensitive high-performance liquid chromatographic method with fluorescence detection for determining the enantiomers of methamphetamine and its major metabolites, amphetamine and p-hydroxymethamphetamine, in urine samples was developed. Using a newly developed reagent for amines, namely, 4-(4,5-diphenyl-1H-imidazol-2-yl)benzoyl chloride, six enantiomers were derivatized under mild conditions (i.e., 10 min at room temperature, pH 9.0) and separated isocratically on a cellulose tris(3,5-dimethylphenylcarbamate) coated silica gel column following a pre-separation on an ODS column within 42 min, and the effluent was monitored at 440 nm (lambda ex 330 nm). Calibration curves for these derivatives using spiked human urine were linear in the range 0.05-100 mumol dm-3 with correlation coefficients > or = 0.999. The detection limits at a signal-to-noise ratio of 3 were 2.8-8.8 fmol per 5 microliters injection. The relative standard deviations of within- (n = 6) and between-day (n = 5) variations were < or = 7.4%. The method was successfully applied to discriminate between (S)-(+)-methamphetamine and its corresponding metabolites found in abusers' urine and their antipodes in a sample taken from a Parkinsonian patient on selegiline (Deprenyl) therapy.

Quality evaluation by capillary electrophoresis of amphotericin B injection after filtration through various membrane filters

The determination of amphotericin B, an antifungal agent, was developed using micellar electrokinetic capillary chromatography (MEKC) with a diode array detector. Repeatability and intermediate precision of MEKC analysis were acceptable. A high correlation was found between amphotericin B levels in pharmaceutical solutions obtained by MEKC and those by high-performance liquid chromatography (HPLC) (r = 0.994). This MEKC method is therefore useful for the determination of amphotericin B. The concentration of amphotericin B did not significantly change after filtration through polyethersulfone (PES, 0.2 microm) and polyvinylidene difluoride (PVDF, 0.45 microm) membrane filters. When the Fungizone injection was filtered through PES (0.2 microm) and added to 5% dextrose for injection (500 mL), particulate matters larger than 10 microm decreased by 64% to a level under the standard defined by United States Pharmacopoeia (USP XXIII). PVDF filtration (0.45 microm) did not have this effect. Our results suggest that filtration of Fungizone injection through PES (0.2 microm) membrane filters is recommended for the preparation of intravenous amphotericin B fluid.

Inverse effects of 20K and 22K human growth hormones on the growth of T-47D human breast cancer cells in culture and in nude mice

The major form of human growth hormone (22K hGH) stimulates the growth of T-47D human breast cancer cells in culture and in nude mice by binding to their receptors for growth hormone and prolactin. Another isoform of hGH having a smaller molecular mass (20K hGH) is known to show different binding affinities to these receptors. In this study, we have analyzed the effects of 20K hGH on the growth of T-47D cells in vitro and in vivo. 20K hGH (50 ng/ml) inhibited the proliferation and DNA synthesis of T-47D cells cultured in the presence and absence of 17 beta-estradiol (100 ng/ml), while 22K hGH (50 ng/ml) promoted the cellular growth. In estradiol-treated nude mice, 22K hGH (100 micrograms) remarkably promoted the growth of T-47D tumor, but 20K hGH again suppressed the tumor growth significantly. The results suggest the presence of different signal pathways for these two hGH isoforms and imply a possible clinical application for 20K hGH.

Basic and clinical studies on ApoE gene typing by line probe assay (LiPA) as a biological marker for Alzheimer's disease and related disorders: multicenter study in Japan

The fundamental reagent capability and clinical significance of ApoE gene typing has been investigated. The result of each test shows that the reagent capability satisfied the expected standard. Four-hundred thirty-nine samples classified into three groups (Alzheimer's disease (AD), other types of dementia and nondementia) were measured to examine the clinical significance. The rate of epsilon 4 genotype of each group was 31.5%, 14.6%, 10.4%, respectively. The AD group had a higher rate than the other groups (p < 0.001). The measurement of ApoE genotype is suggested to be useful as one of the guidelines in the diagnosis of AD.

Expression and purification of a mutant human growth hormone that is resistant to proteolytic cleavage by thrombin, plasmin and human plasma in vitro

The region having a sequence from amino acid 134 to 150 in human growth hormone (hGH) is known to be cleaved by proteases in human plasma, plasmin and thrombin. In this study, oligonucleotide primer-directed mutagenesis was used to produce recombinant mutant hGHs resistant to limited proteolysis by these proteases. Substitution of Arg134 and Thr135 of hGH with Asp134 and Pro135 yielded a thrombin-resistant hGH mutant, and substitution of Arg134, Thr135 and Lys140 with Asp134, Pro135 and Ala140 yielded a plasmin-resistant hGH mutant. The latter mutant hGH was also insensitive to in vitro proteolysis by human plasma incubated for 7 days. These alterations in amino acid residues of hGH did not disrupt its biological conformation and retained full growth promoting activities on rat Nb2 cells and human T-47D breast cancer cells.

Comparison of the effects of thyroxine and triiodothyronine on protein turnover and apoptosis in primary chick muscle cell cultures

Primary chick muscle cells were treated with physiological level of thyroxine (T4) or triiodothyronine (T3) to examine the effects of the hormones on growth, protein turnover, and apoptosis of the cells. Creatine kinase activity, as an index of differentiation, was increased by both T4 and T3. Even when the conversion from T4 to T3 was blocked by iopanoic acid, T4 increased creatine kinase activity. The rate of protein degradation estimated from [3H] tyrosine release was increased by T3 but not by T4. DNA cleavage and fragmentation, as indices of apoptosis, were induced by T3 but not by T4. These results show that T4 stimulates cell differentiation but not protein degradation and apoptosis in primary chick muscle cells, while all events are stimulated by T3.

Gene and cDNA structures of flounder insulin-like growth factor-I (IGF-I): multiple mRNA species encode a single short mature IGF-I

To understand the comprehensive mechanisms of gene expression and processing for insulin-like growth factor-I (IGF-I) in vertebrates, we have investigated the gene organization, promoter and transcriptional initiation sites, alternative splicing and polyadenylating sites, and the cDNA structures of this gene in the Japanese flounder, Paralichthys olivaceus. The flounder IGF-I gene was found to be composed of five exons and four introns spanning 17.5 kb. By Northern blot analysis, two major mRNA classes of 4.7 kb and 2.9 kb were found in the liver. cDNA cloning and reverse transcription polymerase chain reaction (RT-PCR) analysis indicated that these two mRNA classes result from two different-sized 3'-noncoding regions generated by alternative usage of two polyadenylating signals. Further analysis by RT-PCR and sequencing revealed that these mRNA classes both contain two subclasses of mRNA encoding two forms of IGF-I prepropeptide, preproIGF-I-1 and preproIGF-I-2. The two forms of preproIGF-I share the identical signal peptide and mature IGF-I domain but contain different E domains as a result of alternative splicing in exon 3. The mature form of flounder IGF-I was found to comprise 68 amino acid residues, showing a small molecular weight, 7486. In the 5'-flanking region, one major and four minor transcription start sites have been identified by ribonuclease protection assay between -230 and -130 from the translation initiation codon, but no canonical TATA box or GC box was detected in their upstream regions up to -724. The results suggest that some unknown transcription initiation factors are functioning in the promotion of IGF-I gene expression.

Apoptotic cell death induced by local brain hyperthermia in a rat glioma model

Hyperthermia has been shown to inhibit glioma growth both in vitro and in vivo, and has been reported to induce apoptosis of a variety of cells. We investigated the role of apoptosis in tumor cell death following hyperthermia in a rat glioma model representing human glioblastoma. Apoptotic cell death was evaluated by terminal deoxyribonucleotidyl transferase-mediated dUTP-biotin nick end-labeling (TUNEL) and hematoxylin and eosin (H & E) staining. We also examined c-Jun expression immunohistochemically. Apoptotic cell death in rat brain tumors that grew after implantation of C6 glioma cells showed regional differences. In all rats, apoptotic cells, characterized by extreme chromatin condensation and fragmented nuclei with apoptotic bodies in H & E-stained sections, were observed in the gliomas' necrotic cores. TUNEL-positive cells were observed in the border zones between necrotic and vital tumor cells. Before hyperthermia, TUNEL-positive cells were sporadically distributed in the vital tumor tissue. After hyperthermia, the number of TUNEL-positive cells in the peripheral region of the tumor mass increased significantly, reached a peak after 6 h and returned to the basal level within 24 h (P < 0.01). C-Jun protein immunoreactivity was not observed in the cells at the tumor periphery. These data indicate that significantly apoptotic cell death unrelated to c-Jun expression occurs after hyperthermia, and that this form of cell death may be the mechanism of tumor regression following hyperthermia treatment of intracranial gliomas.

Cooperative and differential effects of estrogen, prolactin, 22K and 20K human growth hormones on cyclin D1/PRAD1 gene expression in T-47D human breast cancer cells

The cyclin D1/PRAD1 gene is correlated with carcinogenesis of human breast cancer. In this study, we have analyzed effects of breast cancer-related hormones on the cyclin D1 gene expression in T-47D human breast cancer cells. Estradiol (E2) and human prolactin (hPRL) equally enhanced the cyclin D1 gene expression in the cells, and 22 and 20 kDa human growth hormones (22K and 20K hGHs) showed less stimulatory effects. In the presence of E2, however, hPRL or 22K hGH showed additive stimulations of the cyclin D1 gene expression to that by E2 alone, while 20K hGH did not show any additive stimulation of the gene expression. The results suggest that the signal pathways through estrogen and hPRL receptors are important for cyclin D1 gene expression in breast cancer cells, and that 20K hGH has little effect on the cyclin D1 gene expression in these cells because of its lower affinity to PRL receptor.

An Arabidopsis gene family encoding DRE/CRT binding proteins involved in low-temperature-responsive gene expression

In higher plants, a cis-acting element, DRE/CRT, is involved in gene expression responsive to drought and low-temperature stress. To understand signal transduction pathways from the cold stress signal to gene expression, we characterized a gene family for DRE/CRT-binding proteins DREB1A and CBF1 in Arabidopsis thaliana. DREB1A and CBF1 were shown to be involved in low-temperature-responsive gene expression. We screened an Arabidopsis genomic DNA library with the cDNA fragment of DREB1A as a probe and isolated DREB1A and 2 related genes, DREB1B (= CBF1) and DREB1C. These were arrayed in the order B, A, C in an 8.7 kb region of Arabidopsis chromosome 4. Northern blot analysis using gene-specific probes showed that the 3 DREB1 genes are induced mainly by cold stress but not by osmotic stress in leaves, roots, and stems. Several conserved sequences were found in the promoter regions of all 3 genes. The beta-glucuronidase (GUS) reporter gene driven by the DREB1 promoters was induced at transcriptional level by low temperature in transgenic Arabidopsis plants.

Chemiluminescence-based detection: principles and analytical applications in flowing streams and in immunoassays

The present paper provides the principles of chemiluminescence (CL) and its powerful applications in analytical chemistry, mainly in the area of flow injection analysis, column liquid chromatographic and capillary electrophoretic separating systems, and its potential in immunoassays. CL is light produced by a chemical reaction. The most common advantages of chemiluminescent reactions are the relatively simple instrumentation required, the very low detection limits and wide dynamic ranges, which have contributed to the interest of CL detection in flow injection analysis, high performance liquid chromatography, including miniaturized systems, and, most recently, the exploding area of capillary electrophoresis. The latter powerful microanalytical separation technique offers high numbers of theoretical plates and relatively short analysis times requiring only small sample volumes, the migrating system comprising aqueous buffer solutions. In non-isotopic immunoassays, covering a great variety of applications in human and veterinary medicine, forensic medicine, agriculture and food industry, the radioisotope is replaced by a fluorescence or chemiluminescent label. The use of CL as a detection principle permits quantitative determination of various compounds at low concentrations. Disadvantages of the CL-based technique may include lack of sufficient selectivity and sensitivity to various physicochemical factors.