Acute monocytic leukaemia in a cat

A three-year-old cat with lymphadenopathy, non-regenerative anaemia and marked leucocytosis (171.3 x 10(9) white blood cells/l) was diagnosed with monocytic leukaemia and treated with a combination of anticancer drugs. A number of mature and immature monocyte-like cells were detected in the peripheral blood and bone marrow; they proved to be monocytic cells by cytochemical examination and an analysis of their cell surface phenotype, indicating that the cat suffered from acute myeloid leukaemia, subclassified as monocytic leukaemia (M5). Treatment with cytarabine, doxorubicin, vincristine and prednisolone greatly reduced the number of blast cells in the cat's peripheral blood and bone marrow. The cat was in partial remission for 67 days and survived for 95 days after it was first examined.

The complete nucleotide sequence and multipartite organization of the tobacco mitochondrial genome: comparative analysis of mitochondrial genomes in higher plants

Tobacco is a valuable model system for investigating the origin of mitochondrial DNA (mtDNA) in amphidiploid plants and studying the genetic interaction between mitochondria and chloroplasts in the various functions of the plant cell. As a first step, we have determined the complete mtDNA sequence of Nicotiana tabacum. The mtDNA of N. tabacum can be assumed to be a master circle (MC) of 430,597 bp. Sequence comparison of a large number of clones revealed that there are four classes of boundaries derived from homologous recombination, which leads to a multipartite organization with two MCs and six subgenomic circles. The mtDNA of N. tabacum contains 36 protein-coding genes, three ribosomal RNA genes and 21 tRNA genes. Among the first class, we identified the genes rps1 and psirps14, which had previously been thought to be absent in tobacco mtDNA on the basis of Southern analysis. Tobacco mtDNA was compared with those of Arabidopsis thaliana, Beta vulgaris, Oryza sativa and Brassica napus. Since repeated sequences show no homology to each other among the five angiosperms, it can be supposed that these were independently acquired by each species during the evolution of angiosperms. The gene order and the sequences of intergenic spacers in mtDNA also differ widely among the five angiosperms, indicating multiple reorganizations of genome structure during the evolution of higher plants. Among the conserved genes, the same potential conserved nonanucleotide-motif-type promoter could only be postulated for rrn18-rrn5 in four of the dicotyledonous plants, suggesting that a coding sequence does not necessarily move with the promoter upon reorganization of the mitochondrial genome.

Low-coherence tandem interferometer for measurement of group refractive index without knowledge of the thickness of the test sample

A new low-coherence interferometric technique is proposed for measuring the group refractive indices of dispersive samples with high accuracy. A tandem configuration of interferometers is used to compensate for the asymmetrical distortion of interferograms that results from the broad spectrum of the light source. The group refractive index can be measured without knowledge of the geometrical thickness of the sample under test. The proposed technique can successfully measure even a thick sample. Computer calculations have shown the effectiveness of the proposed technique, which was verified by preliminary experiments; the difference between the experimental result and the catalog data was 7 x 10(-4).

Broad-spectrum frequency comb generation and carrier-envelope offset frequency measurement by second-harmonic generation of a mode-locked fiber laser

A frequency comb spanning more than one octave has been achieved by injecting the second-harmonic generation (780 nm) of a mode-locked fiber laser (1.56 microm) into a photonic crystal fiber. We propose and realize a novel interferometric scheme for observing the carrier-envelope offset frequency of the frequency comb. Frequency noise has been observed on the measured carrier-envelope offset frequency, which has been confirmed to be generated in the photonic crystal fiber by comparing the measured beat frequencies between cw lasers and frequency combs before and after the photonic crystal fiber. The mode-locked fiber laser is considered to be an important candidate for the light source used in realizing a compact optical frequency measurement system including applications in the telecommunication bands.

Heterodyne Fourier transform spectrometer for the near- infrared region

A Fourier transform spectrometer with heterodyne modulation achieved by a moving diffraction grating has been developed for the near-infrared (NIR) region. The grating simultaneously acts as a beam splitter and a modulator, which realizes the optical frequency shift of incident light for increasing the sensitivity of measurements by the heterodyne detection technique. The differences in diffraction angle among broad spectra are compensated by a collimating mirror and plane mirrors. The proposed spectrometer is used for the measurements of spectra in the NIR region. The signal-to-noise ratio of measurements is improved sevenfold with a heterodyne modulation of 410 Hz. As examples, this spectrometer is applied for quantitative calibration and discrimination of organic solutions. The measurement of transmission spectra of a grape is also demonstrated.

The complete sequence of the rice (Oryza sativa L.) mitochondrial genome: frequent DNA sequence acquisition and loss during the evolution of flowering plants

The entire mitochondrial genome of rice (Oryza sativa L.), a monocot plant, has been sequenced. It was found to comprise 490,520 bp, with an average G+C content of 43.8%. Three rRNA genes, 17 tRNA genes and five pseudo tRNA sequences were identified. In addition, eleven ribosomal protein genes and two pseudo ribosomal protein genes were found, which are homologous to 13 of the 16 genes for ribosomal proteins in the mitochondrial genome of the liverwort (Marchantia polymorpha). A greater degree of variation in terms of presence/absence and integrity of genes was observed among the ribosomal protein genes and tRNA genes of rice, Arabidopsis and sugar beet. Transcription and post-transcriptional modification (RNA editing) in the rice mitochondrial sequence were also examined. In all, 491 Cs in the genomic DNA were converted to Ts in cDNA. The frequency of RNA editing differed markedly depending upon the ORF considered. Sequences derived from plastid and nuclear genomes make up 6.3% and 13.4% of the mitochondrial genome, respectively. The degree of conservation of plastid sequences in the mitochondrial genome ranged from 61% to 100%, suggesting that sequence migration has occurred very frequently. Three plastid DNA fragments that were incorporated into the mitochondrial genome were subsequently transferred to the nuclear genome. Nineteen fragments that were similar to transposon or retrotransposon sequences, but different from those found in the mitochondrial genomes of dicots, were identified. The results indicate frequent and independent DNA sequence flow to and from the mitochondrial genome during the evolution of flowering plants, and this may account for the range of genetic variation observed between the mitochondrial genomes of higher plants.

Chitin synthase 1 gene of Arthroderma benhamiae isolates in Japan

In the present study, the chitin synthase 1 (CHS1) gene of eight clinical isolates of Arthroderma benhamiae in Japan was investigated. Nucleotide sequence analysis of the CHS1 gene fragments from clinical isolates of A. benhamiae and from standard strains of Americano-European race and African race A. benhamiae indicated more than 90% similarities among these dermatophytes. An especially high degree of similarity was noted in nucleotide sequence CHS1 gene fragments, with more than 99% among eight clinical isolates and standard strains of the Americano-European race of A. benhamiae. The phylogenetic analysis of their sequences revealed that the eight clinical isolates and the standard strains of the Americano-European race of A. benhamiae were included in the same cluster, and that the African race of A. benhamiae formed a cluster that was distinct from the Americano-European race of A. benhamiae, A. simii and A. vanbreuseghemii.

Molecular identification of Trichophyton rubrum isolate from a dog by chitin synthase 1 (CHS1) gene analysis

A nonsporulating isolate from a dog with dermatophytosis was identified as Trichophyton rubrum by molecular analysis. The nucleotide sequence analysis of the chitin synthase 1 (CHS1) gene from the isolate indicated more than 99% sequence similarity with other human and canine isolates of T rubrum. The molecular typing suggested that isolates of T. rubrum from human and canine sources were genetically identical.

[Troubles inherent to long-term home parenteral nutrition (HPN) and the use of technologies to improve communication between medical institutions and patients]

The continuous advance of technology has contributed to the improvement of the quality of life of patients under long-term home parenteral nutrition (HPN). But the longer the patient stays home, the higher the risk of many kinds of troubles. We designed an HPN system in June 1999, which uses E-mail for patients and to contact with each other (including the patient's family) and to prevent troubles from worsening. We describe the case of a patient which shows the efficacy and usefulness of our system, which makes use of the Internet, video mail, voice mail and electric medical records.

Dominant-negative mutation of p53 tumor suppressor gene in endometrial carcinoma

BACKGROUND

It has been suggested that mutation of the TP53 tumor suppressor gene is involved in endometrial carcinogenesis. However, the status of p53 function in endometrial cancers has not yet been investigated in detail.

METHODS

We surveyed inactivating p53 mutations in endometrial carcinomas using the yeast p53 functional assay, which can evaluate the transcriptional activity of p53 in vivo in yeast. To the detected p53 mutants, we also applied a transdominance assay, which assesses the dominant-negative property of mutants.

RESULTS

Of 23 endometrial carcinomas, 9 tumors (39.1%) were found to harbor p53 mutations. Only 1 of the 6 mutants in 18 endometrioid-type tumors showed dominant-negative capacity. In contrast to the endometrioid-type tumor, all 3 mutations in 5 serous-type tumors (R273H, 9-bp deletion in codons 240-243, and R248W) showed dominant-negative capacity and presented in a homozygous state in the tumors, indicating a complete functional inactivation.

CONCLUSIONS

Although this study included a relatively small number of cases and therefore is a preliminary study, these results suggest that the dominant-negative mutation of the TP53 gene is related to serous adenocarcinoma. The role of the dominant-negative status of p53 mutants in endometrial carcinogenesis and progression of this disease should be further investigated.

A case of POEMS syndrome with high concentrations of interleukin-6 in pericardial fluid

The POEMS syndrome (plasma cell dyscrasia with polyneuropathy, organomegaly, endocrinopathy of various forms, monoclonal gammopathy, skin changes) is a rare multisystem disorder of unknown pathogenesis. Overexpression of proinflammatory cytokines has been implicated in the pathogenesis of POEMS syndrome, however, it is not known whether there is an association between abnormalities in cytokines and pericardial fluid. We present a case of POEMS syndrome with high concentrations of interleukin-6 (IL-6) in pericardial fluid. In our patient, pericarditis developed into cardiac tamponade, and the concentration of IL-6 in pericardial fluid was remarkably elevated compared with that in serum (1760 vs. 6.57 pg mL(-1)). We suggest that IL-6 is associated with the progression or maintenance of pericarditis as a result of POEMS syndrome.

Diabetic ketoacidosis associated with recurrent pulmonary edema and rhabdomyolysis in a patient with Turner's syndrome

Turner's syndrome is a condition involving total or partial absence of one X chromosome and has been associated with a number of diseases including non insulin dependent diabetes mellitus, abnormalities of glucose metabolism and hypothreosis. There have been many case reports in which Turner's syndrome is associated with type 2 diabetes, but the association with type 1 diabetes and/or life threatening complications is very rare. We present an unusual case of a patient with Turner's syndrome who has type 1 diabetes and is complicated with ketoacidosis, severe acute and recurrent pulmonary edema and rhabdomyolysis.

Multiple oral squamous epithelial lesions: are they genetically related?

The development of second primary tumors (SPTs) in patients with head and neck squamous cell carcinoma (HNSCC) has become an increasingly important factor in clinical treatment decisions. Currently, clinical and histologic parameters are used to determine whether or not SPT is present. Recent studies suggest that many SPTs in the upper aerodigestive tract have a common clonal origin, challenging the longstanding multiclonal origin concept. To determine genetic relationships among multiple oral cancerous and precancerous lesions (MOCP), we analysed 100 lesions from 26 Japanese patients. Lesion development was synchronous and metachronous. We looked for patterns of microsatellite alterations (MA) using seven markers at chromosomes 3p14, 9p21, and 17p13, where MA occurs early in oral carcinogenesis. Loss of heterozygosity (LOH) was found in 52.6% (41/78), 62.5% (60/96), and 59.3% (32/54) of informative MOCP at 3p14, 9p21, and 17p13, respectively. Microsatellite instability (MI) was observed in 11, 26 and 13% of the samples at 3p14, 9p21, and 17p13 markers, respectively. Patterns of MA were concordant in only nine (14%) of 63 lesions from four (18%) of 22 patients who initially presented with noninvasive lesions. However, two of four patients with invasive cancer as indexed lesion showed 16 (43%) clonally related MOCP among 37 lesions (P=0.003). The results suggest that the majority of MOCP arise from clonally independent cells affected by field cancerization. However, the probability of mucosal spread of clonal malignant or premalignant cells may increase along with malignant progression.

Interaction of MCC2, a novel homologue of MCC tumor suppressor, with PDZ-domain Protein AIE-75

AIE-75 is a protein identified as an autoantigen in patients with autoimmune enteropathy and as a colon cancer-related antigen. It has recently been assigned to be a causative gene for Usher type 1C congenital syndromic hearing loss. The novel protein has three PSD-95/Dlg/ZO-1 (PDZ) protein-protein interaction domains and is therefore implicated to function as a molecular anchor or sorter. We have identified a novel protein that binds to AIE-75 by yeast two-hybrid screening. The protein has a high homology to the tumor suppressor MCC (mutated in colon cancer; or MCC1 hereafter) and was named MCC2. MCC2 protein binds the first PDZ domain of AIE-75 with its C-terminal amino acids -DTFL. Since the MCC1 does not bind to AIE-75 and the MCC2 displays different expression patterns in various organs compared to MCC1, they appear to play distinct roles in cells. The MCC2 gene is located on chromosome 19p13 in the vicinity of APCL gene, while MCC1 maps near to APC tumor suppressor gene. Because of negative expression of MCC2 in a panel of cancer cell-lines compared to the corresponding normal tissues, we suggest that further study is necessary to investigate a possible role of MCC2 as a tumor suppressor.

Fulminant Mycoplasma pneumoniae pneumonia

A 64-year-old woman, who was previously in good health was admitted because of progressive respiratory distress. Her chest radiograph revealed bilateral widespread alveolar infiltrates. She was given a diagnosis of pneumonia caused by Mycoplasma pneumoniae serologically, acute respiratory distress syndrome, and disseminated intravascular coagulation. She died of multiple organ failure despite intensive therapy with mechanical ventilation, intravenous erythromycin and corticosteroids, continuous hemodiafiltration, and plasma exchange. Although Mycoplasma pneumoniae infection is usually a benign self-limited disease, this case emphasizes its potentially serious nature even in normal healthy individuals.

The gene for alternative oxidase-2 (AOX2) from Arabidopsis thaliana consists of five exons unlike other AOX genes and is transcribed at an early stage during germination

We investigated the expressions of genes for alternative oxidase (AOX1a, AOX1b, AOX1c and AOX2) and genes for cytochrome c oxidase (COX5b and COX6b) during germination of Arabidopsis thaliana, and examined oxygen uptakes of the alternative respiration and the cytochrome respiration in imbibed Arabidopsis seeds. A Northern blot analysis showed that AOX2 mRNA has already accumulated in dry seeds and subsequently decreased, whereas accumulation ofAOX1a mRNA was less abundant from 0 hours to 48 hours after imbibition and then increased. The increase of the capacity of the alternative pathway appeared to be dependent on the expressions of both AOX2 and AOX1a. On the other hand, steady-state mRNA levels of COX5b and COX6b were gradually increased during germination, and the capacity of the cytochrome pathway was correlated with the increase of expressions of the COX genes. Antimycin A, the respiratory inhibitor, strongly increased the expression of AOX1a but had no effect on the expression of AOX2. A 5'RACE analysis showed that AOX2 consists of five exons, which is different from the case of most AOX genes identified so far. Analysis of subcellular localization of AOX2 using green fluorescent protein indicated that the AOX2 protein is imported into the mitochondria.

Regulation of FRTL-5 thyroid cell growth by phosphatidylinositol (OH) 3 kinase-dependent Akt-mediated signaling

Thyrotropin (TSH)-initiated cell cycle progression from G1 to S phase in FRTL-5 thyroid cells requires serum, insulin, or insulin-like growth factor 1 (IGF-1) and involves activation of 3-hydroxy-3-methylglutaryl-CoA reductase, geranylgeranylation of RhoA, p27Kip1 degradation, and activation of cyclin-dependent kinase (cdk) 2. In the present report, we show that the serine-threonine kinase Akt is an important mediator of insulin/IGF-1/serum effects on cell cycle progression in FRTL-5 thyroid cells. The phosphoinositol (OH) 3 kinase inhibitors, Wortmannin (WM) and Ly294002 (LY), block the ability of insulin/IGF-1 to reduce p27 expression, to induce expression of cyclins E, D1, and A as well as cdk 2 and 4, and to phosphorylate retinoblastoma protein. They also inhibit insulin/IGF-1-increased DNA synthesis and cell cycle entrance (S+G2/M). Insulin/IGF-1 rapidly induced activation of Aktl in a PI3 kinase-dependent manner, and increased Aktl RNA levels. Most importantly, FRTL-5 cells transfected with a constitutively active form of Aktl have higher basal rates of DNA synthesis and no longer require exogenous insulin/IGF-1 or serum for TSH-induced growth. In sum, Aktl appears to have an important role in insulin/IGF-1 regulation of FRTL-5 thyroid cell growth and cell cycle progression.

New eudesmane sesquiterpenes from the root of Lindera strychnifolia

Strychnistenolide (1) and its acetate 2 were isolated from the root of Lindera strychnifolia, along with a novel rearranged type of secoeudesmane, strychnilactone (3). Their structures were elucidated by extensive analysis of their NMR spectra, including 2D NMR techniques, together with an X-ray analysis for 3. Strychnistenolide exists as a single stereoisomer in CHCl(3), but in pyridine is epimerized.

Inactivate the remaining p53 allele or the alternate p73? Preferential selection of the Arg72 polymorphism in cancers with recessive p53 mutants but not transdominant mutants

Several reports have noted epidemiological differences in the prevalence or prognostic significance of p53 mutants with arginine (R) or proline (P) at the codon 72 polymorphism (R72/P72) in certain cancer types, but the biological significance of these variants is unclear. The ability of p53 mutants to interact with and inactivate the p53 homolog p73 was recently reported to depend on the conformational state of the p53 protein and the residue at codon 72. Since the conformation of p53 mutants may influence their ability to transdominantly inhibit wild-type p53, we tested whether there was a correlation between the amino acid at codon 72 and the transdominance of p53 alleles found in tumors. The transdominance test was performed using a simple yeast transcription assay, and the amino acid at codon 72 was determined by sequencing. A total of 100 p53 mutants were tested. Compared with the germline frequency (R:P = 427:297), an extreme bias in favor of the R72 allele was observed with recessive mutants (R:P = 50:7, P < 0.0002), whereas no selection for the R72 allele was seen with transdominant mutants (R:P = 23:20). p53 and p73 are known to transactivate overlapping sets of target genes. We interpret the R72 bias with recessive mutants as evidence that decreased activation of p53 target genes provides a selective growth advantage to tumor cells during the stage of tumorigenesis in which a wild-type and mutant p53 allele coexist. We suggest that transdominant p53 mutants achieve this by inactivation of the remaining wild-type p53 allele, whereas recessive p53 mutants achieve it through inactivation of p73.

Characterization and expression of the genes for cytochrome c oxidase subunit VIb (COX6b) from rice and Arabidopsis thaliana

Many of the subunits of cytochrome c oxidase (COX) in the mitochondria of higher plants are encoded by nuclear genes. These genes are less characterized compared to mitochondrial-encoded genes. We previously isolated a cDNA encoding COX6b (designated OsCOX6b1 in this study) from the rice nuclear genome and analyzed its expression. The deduced protein had an extended N-terminus compared with human and yeast COX6b proteins. In this study, we identified another COX6b gene (OsCOX6b2) in rice and revealed that it was actually expressed. The deduced protein of this gene did not have an extended N-terminus and had about the same size as the human and yeast proteins. Genomic Southern hybridization analysis revealed that there was at least one OsCOX6b-homologus sequences in the rice genome other than OsCOX6b1 and OsCOX6b2. Furthermore, we identified three COX6b genes in a dicotyledonous plant, Arabidopsis thaliana. One of these genes (AtCOX6b1) was relatively long, with a length similar to that of OsCOX6b1, and the other two (AtCOX6b2 and AtCOX6b3) were shorter, with lengths similar to the length of OsCOX6b2. Genomic Southern hybridization analysis indicated there were no additional COX6b genes in the Arabidopsis genome. The coding regions of OsCOX6b1 and AtCOX6b1 were separated by four introns and those of OsCOX6b2, AtCOX6b2 and AtCOX6b3 were separated by three introns. A Northern hybridization analysis showed that OsCOX6b1, AtCOX6b1 and AtCOX6b3 were expressed in all organs examined, although with some differences in the amount of expression among the organs. OsCOX6b2 and AtCOX6b2 were strongly expressed in roots but most of the transcripts of AtCOX6b2 were degraded. The evolution of COX6b genes from rice and Arabidopsis is discussed.

Numerous and highly developed tubular projections from plastids observed in Tobacco epidermal cells

Tubular projections from plastids (stromules) were observed using a stroma-targeted green fluorescent protein (GFP) fusion protein and a confocal laser scanning microscope. In tobacco (Nicotiana tabacum) epidermal cells, stromules were observed at a high frequency. Some of them were long and connected plastids. Three days after particle bombardment, 80.6+/-6.99% of the transformed cells contained some plastids with more than one stromule, and 40.2+/-7.7% contained at least one pair of plastids connected by stromules. In a few cells, numerous and highly developed stromules covering the whole cell were observed. Stromules were also observed in epidermal cells in each of three other plant species that were tested: rice, dayflower (Commelina communis) and Arabidopsis thaliana. These findings demonstrated that stromules are common structure in plant epidermal cells.

Murine homologs of deltex define a novel gene family involved in vertebrate Notch signaling and neurogenesis

Notch signaling plays an important role in cell-fate specification in multicellular organisms by regulating cell-cell communication. The Drosophila deltex gene encodes a modulator of the Notch pathway that has been shown to interact physically with the Ankyrin repeats of Notch. We isolated four distinct cDNAs corresponding to mouse homologs of deltex - mouse Deltex1 (MDTX1), mouse Deltex2 (MDTX2), mouse Deltex2DeltaE (MDTX2DeltaE), and mouse Deltex3 (MDTX3). Deduced amino acid sequences of these four cDNAs showed a high degree of similarity to Drosophila Deltex and its human homolog, DTX1 throughout their lengths, even though they possess distinct structural features. MDTX proteins formed homotypic and heterotypic multimers. We found that these genes were expressed in the central, peripheral nervous system and in the thymus, overlapping with those of mouse Notch1. In mammalian tissue culture cells, overexpression of any of the four mouse deltex homologs suppressed the transcriptional activity of E47, a basic helix-loop-helix (bHLH) protein, in a manner similar to suppression by an activated form of human Notch1 or human DTX1. In addition, overexpression of MDTX2 and MDTX2DeltaE in C2C12 cells under differentiation-inducing conditions suppressed the expression of myogenin, one of the myogenic transcriptional factors; this was also similar to a previously reported activity of constitutively activated Notch. Furthermore, misexpression of any of the MDTX genes in Xenopus embryos resulted in an expansion of the region expressing the neural cell adhesion molecule (N-CAM) gene, a marker for the neuroepithelium. Collectively, our results suggest that these mouse deltex homologs are involved in vertebrate Notch signaling and regulation of neurogenesis.