mRNA Transcript abundance during plant growth and the influence of Li(+) exposure.

Lithium (Li) toxicity in plants is, at a minimum, a function of Li(+) concentration, exposure time, species and growth conditions. Most plant studies with Li(+) focus on short-term acute exposures. This study examines short- and long-term effects of Li(+) exposure in Arabidopsis with Li(+) uptake studies and measured shoot mRNA transcript abundance levels in treated and control plants. Stress, pathogen-response and arabinogalactan protein genes were typically more up-regulated in older (chronic, low level) Li(+)-treatment plants and in the much younger plants from acute high-level exposures. The gene regulation behavior of high-level Li(+) resembled prior studies due to its influence on: inositol synthesis, 1-aminocyclopropane-1-carboxylate synthases and membrane ion transport. In contrast, chronically-exposed plants had gene regulation responses that were indicative of pathogen, cold, and heavy-metal stress, cell wall degradation, ethylene production, signal transduction, and calcium-release modulation. Acute Li(+) exposure phenocopies magnesium-deficiency symptoms and is associated with elevated expression of stress response genes that could lead to consumption of metabolic and transcriptional energy reserves and the dedication of more resources to cell development. In contrast, chronic Li(+) exposure increases expression signal transduction genes. The identification of new Li(+)-sensitive genes and a gene-based "response plan" for acute and chronic Li(+) exposure are delineated.

T1 signal intensity and height of the anterior pituitary in neonates: correlation with postnatal time.

BACKGROUND AND PURPOSE: The anterior pituitary of a term neonate is usually hyperintense on T1-weighted MR images, which may represent histologic changes of the gland due to the effect of high estrogen levels during the fetal period; however, MR findings of a preterm neonate have not been fully evaluated. The purpose of this study was to investigate whether intensity and size of the neonatal anterior pituitary on MR images obtained near term of corrected age correlates with the gestational age at birth or postnatal time. MATERIALS AND METHODS: Data of 88 consecutive neonates (gestational age, 24-41 weeks; mean, 31.5 weeks) were analyzed. All of the neonates underwent MR imaging at a corrected age of 0 months +/- 4 weeks. Relative signal intensity of the anterior pituitary compared with that of the pons on T1-weighted sagittal images was calculated. Height of the pituitary was also measured. Stepwise regression analysis was performed to evaluate the effects of gestational age at birth and postnatal time on the relative signal intensity and on the pituitary height. RESULTS: The relative signal intensity significantly negatively correlated with postnatal time (P = .001) but not with gestational age at birth (P = .42). Pituitary height significantly negatively correlated with postnatal time (P = .049) but not with gestational age at birth (P = .071). CONCLUSION: A significant negative correlation exists between postnatal time and signal intensity on T1-weighted MR images of the anterior pituitary obtained near term. A nonhyperintense anterior pituitary is a normal MR finding of preterm neonates when imaged near term.

Clinical features of probable medication-overuse headache: a retrospective study in Japan.

This study examined the clinical picture of probable medication-overuse headache (MOH) and the presence of any features peculiar to Japan. In a retrospective study of 47 patients, type of primary headache, type of medicine overused, method and result of withdrawal were investigated. Among the 47 patients, 80.9% had migraine only, and 85.1% overused combination medications. While 36 patients (76.6%) succeeded in withdrawal, five patients (10.6%) failed. One patient (2.1%) had not improved by 2 months after withdrawal and was diagnosed with chronic migraine and chronic tension-type headache without MOH. The remaining five patients (10.6%) dropped out. All dropout patients were recommended abrupt inpatient withdrawal, but chose abrupt outpatient withdrawal. As features peculiar to Japan, many patients with probable MOH overused combination analgesics, particularly females.

Influence of marginal bone resorption on stress around an implant--a three-dimensional finite element analysis.

Average marginal bone resorption of about 1 mm after the first year of functional loading, which is followed by an annual loss of approximately 0.1 mm, has been reported in stable implants. However, finite element analyses on bone stress around implants have been limited to analysing the bone stress in the absence of any bone resorption. Thus, a three-dimensional finite element analysis was performed to compare the bone stresses in a non-resorption model with those in four models with bone resorption of two depths (1.3 and 2.6 mm) and types (horizontal resorption and angular defects). Axial and bucco-lingual forces were separately applied to the center of the superstructure and the maximum equivalent stress was calculated. The main tendencies of bone stress (highest stress concentration around implant neck, higher stresses under bucco-lingual than axial load, as well as in the cortical than cancellous bone) were the same in the non-resorption and resorption models. Bone stress distributions were similar in the non-resorption and horizontal resorption models, but differed from those in the angular defect models. Moreover, the changes of the bone stress values with resorption depth differed for the two resorption types. Thus, in FEA, accurate simulation of the marginal bone shape in the implant neck region is advisable.

Partial biochemical characterisation of collagen in carious dentin of human primary teeth.

The process of dentin caries is a complex event involving demineralisation and matrix degradation. The objective of this study was to biochemically characterise collagen, the major dentin matrix component, by amino acid and cross-link analyses in two distinct carious dentin regions of human primary teeth. Twenty-seven carious primary teeth were obtained from 3 to 11-year-old patients and three layers of dentin, i.e. outer, inner carious dentin and normal dentin, were identified by a 1% acid red solution and dissected from each tooth. The samples were pulverised, the respective layers obtained from three to five teeth were pooled and six samples per layer were analysed. Aliquots of the dried dentin powder were hydrolysed with 6N HCl at 110 degrees C for 24h and subjected to amino acid analyses. Other aliquots were demineralised, reduced with standardised NaB3H4, hydrolysed and subjected to quantitative collagen cross-link analyses. The results demonstrated that in the outer carious layer the collagen-associated amino acids were significantly lower and the reducible cross-links were markedly diminished when compared to the other two groups. There was no significant difference in these parameters between the inner carious and the normal layers. The data indicate that while the collagen in the outer carious dentin is significantly altered and degraded, the one in the inner carious dentin is relatively unaffected in primary teeth.

Metastatic hepatocellular carcinoma of the maxillary sinus: a rare autopsy case without lung metastasis and a review.

A rare case of metastatic hepatocellular carcinoma (HCC) of the maxillary sinus in a 67-year-old man is reported along with the findings at autopsy. A fine needle aspiration biopsy specimen revealed a characteristic tumour structure resembling primary HCC. At autopsy, metastatic lesions were recognized in the bilateral adrenals, spleen, sternum, vertebrae and lymph node at the lesser curvature of the stomach, but not in the lung, suggesting that the HCC had metastasized to the maxillary sinus via the plexus venous vertebralis and/or the azygos vein, or lymph duct. In our reviewed 29 cases of metastatic HCC in the oro-maxillofacial region, most patients were men in the 50- to 70-year age range. At least 11 cases did not have lung metastasis, and in 18, metastasis to the oro-maxillofacial region was the first sign of HCC. One should be aware of the possibility to encounter the oral lesion as first sign of metastatic HCC.

Molecular cloning, sequencing and expression of the gene encoding a novel chitinase A from a marine bacterium, Pseudomonas sp PE2, and its domain structure.

The pchA gene encoding chitinase A (PchA) from a Pythium porphyrae cell-wall-degrading marine bacterium, Pseudomonas sp. PE2, was cloned and characterized. The deduced PchA was a modular enzyme composed of an N-terminal signal peptide, a glycoside hydrolase family 18 catalytic domain that was responsible for the chitinase activity, the chitin-binding domains (ChBDs), and the carbohydrate-binding modules (CBM). The amino acid sequence of ChBD(PchA) was highly conserved in the CBM family 12 that also accommodates ChBDs without an AKWWTQG motif, a domain commonly found in bacterial chitinase and Streptomyces griseus protease C. Interestingly, CBM(PchA) showed significant sequence homology to the C-terminal region of endoglucanase B from Cellvibrio mixtus, which is a member of CBM family 6. This is the first report of a chitinase possessing a domain with high similarity to CBM family 6. Deletion analysis indicated clearly that ChBD(PchA) might play an important role in the binding of native chitin and chitosan, but not processed chitin. CBM(PchA) also appeared to play such a role in the binding of xylan and Avicel. These results suggest that the C-terminal region of PchA might be a key component in the binding of chitin in the cell walls of P. porphyrae or other structural components of marine organisms.

Síndrome de Wolff-parkinson-white em cães. Relato de dois casos

O artigo não apresenta resumo.

Molecular characterization of the breakpoint region associated with a constitutional t(2;15)(q34;q26) in a patient with multiple myeloma.

The molecular cloning of the translocation breakpoints from constitutional chromosome rearrangements in patients with a variety of human diseases has consistently led to the isolation of genes important in the development of the phenotype. We used fluorescence in situ hybridization (FISH) to analyze the breakpoint region of a constitutional chromosome translocation involving regions 2q34 and 15q26 observed in a patient with multiple myeloma (MM), a malignant disorder of plasma cells secreting monoclonal immunoglobulin. FISH analysis of this rearrangement showed that the chromosome 2-specific yeast artificial chromosome (YAC) 914E7 and the chromosome 15-specific YAC 757H6 span the translocation breakpoints, respectively. In order to characterize the location of the breakpoints further, somatic cell hybrids were constructed between mouse NIH3T3 cells and t(2;15)-bearing lymphoblastoid cells. Using these somatic cell hybrids, we have shown that the breakpoint on chromosome 2 lies between D2S3007 and D2S3004 and the chromosome 15 breakpoint lies between D15S107 and WI5967 (D15S836). YAC fragmentation has been used to define a 350 kb region containing the 15q26 breakpoint.

[Automated analysis for determination of PCBs in fish].

An automated analytical method for determination of polychlorinated biphenyls (PCBs) in fish was developed using supercritical fluid extraction (SFE) in combination with an automated sample preparation instrument (Prep) and GC/MS. By incorporating basic alumina with the sample in the extraction process, and optimizing the amount of carbon dioxide used, fish lipid was selectively reduced. The extract was cleaned up on a Florisil cartridge with Prep. The method was evaluated using naturally contaminated tissues and by comparison of automated analytical method results with those obtained by the conventional method. Mean recovery of PCBs from 3 kinds of fish including hairtail, mackerel and yellowtail were 69.8%, 90.2% and 81.1%, respectively. This method is less laborious and requires far less organic solvent than the conventional method, but produced comparable results.

Fine mapping of the PTGFR gene to 1p31 region and mutation analysis in human breast cancer.

The 1p31 chromosomal region shows loss of heterozygosity (LOH) in up to 50% of human breast cancer, indicating the presence of a tumor suppressor gene at this location. Many efforts have been made to identify candidate genes responsible for breast cancer on the short arm of chromosome 1. It was shown that prostaglandins have been implicated in the tumorigenesis pathway, perhaps via interactions with their cell surface receptors. The prostaglandin F2 receptor gene (PTGFR) was tentatively mapped to 1p31 adjacent to the region undergoing LOH in human breast cancer. We undertook a mutation study in 34 sporadic human breast tumors using a variant of SSCP, incorporation PCR SSCP (IPS). Several nucleotide variants were detected in different tumors. Here we report the nature of these nucleotide changes and the possible involvement of the PTGFR gene in the etiology of human cancer.

A transcription map of the minimally deleted region from 13q14 in B-cell chronic lymphocytic leukemia as defined by large scale sequencing of the 650 kb critical region.

Extensive analysis of tumors has demonstrated homozygous and heterozygous deletions in chromosome region 13q14.3 in B-cell chronic lymphocytic leukemia (B-CLL), suggesting the site of a tumor suppressor gene. Since previous searches for this gene have not yielded any viable candidates, we now present the sequence of the BACs which span the minimally deleted approximately 650 kb region between markers D13S319 and D13S25. This sequence has allowed us to create the definitive transcription map for the region which reveals 93 ESTs and 12 Unigene clusters in this region. Using gene prediction programs, a further 19 potential genes are also identified. The genes show an asymmetrical distribution throughout the region with most of them clustering at the extreme ends. This sequencing effort provides for the definitive structure of the B-CLL deletion region and the identification of the vast majority of the potential candidate genes. Of all the genes identified, only three have homologies to known genes: two L1 repeat genes and rabbit epididymal protein 52. This 13q14.3 sequence provides the final substrate from which to characterize the B-CLL tumor suppressor gene.

The partner gene of AML1 in t(16;21) myeloid malignancies is a novel member of the MTG8(ETO) family.

The t(16;21)(q24;q22) translocation is a rare but recurrent chromosomal abnormality associated with therapy-related myeloid malignancies and a variant of the t(8;21) translocation in which the AML1 gene on chromosome 21 is rearranged. Here we report the molecular definition of this chromosomal aberration in four patients. We cloned cDNAs from the leukemic cells of a patient carrying t(16;21) by the reverse transcription polymerase chain reaction using an AML1-specific primer. The structural analysis of the cDNAs showed that AML1 was fused to a novel gene named MTG16 (Myeloid Translocation Gene on chromosome 16) which shows high homology to MTG8 (ETO/CDR) and MTGR1. Northern blot analysis using MTG16 probes mainly detected 4.5 kb and 4.2 kb RNAs, along with several other minor RNAs in various human tissues. As in t(8;21), the t(16;21) breakpoints occurred between the exons 5 and 6 of AML1, and between the exons 1 and 2 or the exons 3 and 4 of MTG16. The two genes are fused in-frame, resulting in the characteristic chimeric transcripts of this translocation. Although the reciprocal chimeric product, MTG16-AML1, was also detected in one of the t(16;21) patients, its protein product was predicted to be truncated. Thus, the AML1-MTG16 gene fusion in t(16;21) leukemia results in the production of a protein that is very similar to the AML1-MTG8 chimeric protein.

A 3-Mb sequence-ready contig map encompassing the multiple disease gene cluster on chromosome 11q13.1-q13.3.

Despite the presence of several human disease genes on chromosome 11q13, few of them have been molecularly cloned. Here, we report the construction of a contig map encompassing 11q13.1-q13.3 using bacteriophage P1 (P1), bacterial artificial chromosome (BAC), and P1-derived artificial chromosome (PAC). The contig map comprises 32 P1 clones, 27 BAC clones, 6 PAC clones, and 1 YAC clone and spans a 3-Mb region from D11S480 to D11S913. The map encompasses all the candidate loci of Bardet-Biedle syndrome type I (BBS1) and spinocerebellar ataxia type 5 (SCA5), one-third of the distal region for hereditary paraganglioma 2 (PGL2), and one-third of the central region for insulin-dependent diabetes mellitus 4 (IDDM4). In the process of map construction, 61 new sequence-tagged site (STS) markers were developed from the Not I linking clones and the termini of clone inserts. We have also mapped 30 ESTs on this map. This contig map will facilitate the isolation of polymorphic markers for a more refined analysis of the disease gene region and identification of candidate genes by direct cDNA selection, as well as prediction of gene function from sequence information of these bacterial clones.

A complete NotI restriction map covering the entire long arm of human chromosome 11.

BACKGROUND: Human chromosome 11 is one of the autosomes on which many disease genes have been mapped. Many different types of map, including a radiation hybrid map, a genetic map, and an STS-content YAC map, have been constructed for the chromosome. However, a physical map providing accurate physical distances has not yet been established. A chromosome-wide NotI restriction map was constructed to understand the overall feature of the genome organization and to facilitate the positional cloning of disease genes. RESULTS: A complete NotI restriction map of the entire long arm of human chromosome 11 was constructed using linking-clone mapping. This physical map covers 77.6Mb, from a pericentromeric NotI site to the terminus, and provides the most accurate ordering and distance estimation to date. We also mapped 138 sequence markers in the q13 region that have been poorly mapped previously. CONCLUSIONS: The restriction map of the entire long arm of human chromosome 11 is the longest restriction map of the human genome. This mapping has disclosed unique features regarding the organization of the chromosome, indicating that restriction sites of NotI, a CpG-recognition enzyme, are primarily distributed in R (or T) bands and that genetic distance is considerably longer in R (or T) bands than in G bands. The mapping, as well as the dense concentration of mapped markers within the q13 region, should help with positional cloning of the genes associated with various diseases.

Metazoan parasites of sika deer from east Hokkaido, Japan and ecological analyses of their abomasal nematodes.

Metazoan parasites of 50 sika deer (Cervus nippon yezoensis) collected in March 1991 in the Ashoro District in east Hokkaido, Japan, were evaluated. Ten species of helminths and three species of ectoparasites were obtained. Estimated abundance of males of two species of abomasal nematodes, Spiculopteragia houdemeri and Rinadia andreevae, were positively correlated with each other, and were overdispersed; S. houdemeri followed Poisson's and R. andreevae followed a negative binomial distribution. No significant relationship was detected between the estimated abundance of males of these two nematode species and nutritional condition of the hosts. Using a general linear model, the fourth-root transformed estimated abundance of male S. houndemeri was influenced by the main effects of host sex and age. This phenomenon was attributable to the ecological and behavioral features of the deer. The low diversity of the abomasal nematode community was regarded as the result of the extinction of some species of nematodes on Hokkaido Island.

Japanese siblings with missense mutation (717Val --> Ile) in amyloid precursor protein of early-onset Alzheimer's disease.

We report Japanese siblings with the missense mutation 717Val --> Ile in the amyloid precursor protein. The maternal grandmother died of an unknown dementing disorder. The proband's mother had gradually increasing amnesia beginning at age 64, which was diagnosed as Alzheimer's disease (AD). She died in a psychiatric hospital (duration of illness: 16 years). Both the proband and her elder sister were affected at about age 55 years. Disturbances of memory, judgment, and emotion, as well as personality changes, occurred first, with dementia eventually predominating. The elder sister died of pneumonia (duration of illness: 9 years). The amyloid precursor protein (APP) gene was analyzed from each sibling. Genomic DNAs obtained from blood samples were amplified by the polymerase chain reaction (PCR) method. PCR products were digested with the restriction enzyme Bcl I. The resulting restriction fragment length polymorphisms (RFLPs) showed the missense mutation 717Val --> Ile in both patients, but not in a normal control. DNA sequencing showed the presence of the 2149G --> A missense mutation only in the patients. We conclude that this familial AD may originate from the missense mutation 717Val --> Ile in the amyloid precursor protein gene and that the clinical picture is typical of AD, except for normal-pressure hydrocephalus and psychiatric phenomena.

[Epidemiological study of the prognosis and relevant factors of demented patients].

One hundred twenty patients diagnosed as having dementia at the Center for Elderly Dementia in Hyogo College of Medicine, were recruited for this study to investigate the factors related to the prognosis of dementia. Patients were classified into the following two groups: those staying at home (group 1); those who died at home (group 2). The proportion of various dementias was almost equal in each group: vascular dementia, 30%; senile dementia of Alzheimer's type, 40%; mixed dementia, 20%; Alzheimer's disease, 10%. The average duration of disease in the two groups were not significantly different. The average age of onset in group 2 was higher than that in group 1. The rate of those with severe dementia was higher in group 2 than group 1. Those in group 2 scored less on the Mini-Mental State examination than those in group 1. Symptoms of dementia were assessed by the modified GBS-scale. In group 2, patients scored higher in impaired intellectual and motor functions. The CT findings suggested cortical atrophy, ventricular enlargement and periventricular lucency more often in group 2 than in group 1. Laboratory findings revealed that decrease in red blood cell count, hemoglobin, hematocrit and serum protein were more apparent in group 2 than group 1. It was considered that impaired motor functions, cortical atrophy, white matter lesions, anemia and malnutrition enhanced the probability of death. The study has confirmed that the prognosis of dementia is not only related to intellectual impairment but also deteriorated physical conditions such as motor dysfunction, anemia and malnutrition.

Acidic-phospholipid deficiency represses the flagellar master operon through a novel regulatory region in Escherichia coli.

The Escherichia coli pgsA3 mutation, which causes acidic-phospholipid deficiency, was found to repress the flagellar master operon, as assessed by the beta-galactosidase activities of flhD-lacZ fusions. This explained the impairment of flagellar formation and motility by the mutation. A series of deletion analysis indicated that a 40-bp region, at the 5' end of the flhD locus examined, was responsible for the repression of a downstream transcription initiation that was catabolite-repression sensitive. This novel regulatory region was 200 bp upstream of the first possible translation initiation site.

Identification and characterization of membrane cofactor protein (CD46) in the human kidneys.

Membrane cofactor protein (MCP, CD46) is an integral protein that serves as a cofactor for factor I in inactivating C3b/C4b deposited on the same cell membrane as C3bi/C4c+C4d. This C3b/C4b inactivation is closely associated with self-protection of host cells from autologous complement attack. We have studied the distribution and properties of MCP in the normal human kidney by immunohistochemical and immunoblotting methods using monoclonal antibodies against MCP. MCP was predominantly expressed on the juxtaglomerular apparatus. Glomerular capillary walls, mesangial areas, and tubulus were also MCP positive. Glomerulus MCP was composed of two major bands of 45-65 kDa, which were similar to those of lymphocyte MCP. The proportion of the high and low molecular weight components in glomerulus MCP, however, was considerably different from that of lymphocyte MCP among the individual samples tested. Glomerular epithelial cells and mesangial cells from an individual having equal amounts of high and low molecular weight components in the lymphocytes were cultured separately and the properties of their MCP investigated. MCP in the mesangial cells and glomerular epithelial cells showed profiles in which the upper band was predominant. The results may explain the unique distribution of the high and low molecular weight forms in the glomerulus. These forms of MCP together with factor I were all capable of inactivating C3b to C3bi. Message analysis suggested that glomerular epithelial cells and mesangial cells synthesized a single species of mRNA of 4.2 kb from which the polymorphic MCP species were generated. Flow cytometric analysis suggested that MCP was minimal in mesangial cells. These results, taken together with the previous reports on the distribution of other complement regulatory proteins, infer that the distribution profile of MCP is rather similar to that of DAF but differs from those of CD59 and CR1 in the normal human kidney; this may reflect the differences between their roles or functional properties in renal tissue.