Identification of the duplicated segments in rice chromosomes 1 and 5 by linkage analysis of cDNA markers of known functions

We mapped two loci for ADP-ribosylation factor homologues (ARF1, ARF2) and two loci for cysteine proteinase inhibitors (oryzacystatin-I and -II: OCI, OCII) by linkage analysis of restriction fragment length polymorphism loci in rice (Oryza sativa L.) genomic DNAs using their cDNAs as probes.Oc-1 andArf-2 were found to be closely located to each other on chromosome 1, whileOc-2 andArf-1,both found on chromosome 5, were also located close to each other. The map distances are about 2 cM in both pairs. In each chromosome, theArf locus was located about 27 cM from that of the aldolase gene (Ald-2 in chromosome 1 andAld-1 in chromosome 5). These three genes are in the same order,Ald-Arf-Oc, but in opposite orientations relative to the distal ends of the linkage group. The presence of two sets of three linked genes on chromosomes 1 and 5 strongly suggests a structural similarity of the blocks of the two chromosomes, which probably reflects duplication of the segment. A recent investigation by other workers has shown that these rice blocks correspond to two regions in maize chromosomes 8 and 6, that have previously been shown to share many duplicated nucleotide sequences. It is therefore very likely that the duplication of the region occurred before the divergence of rice and maize during the evolution of the subfamilies of the grasses (Gramineae). In view of a recently discovered possible structural similarity between the small GTP-binding protein superfamily, which includesArf andras proteins, and the cystatin family, the close linkage ofOc andArf loci found in the present study suggests a possible cluster of genes related to the small GTP-binding proteins.

Adult T-cell leukaemia with various abnormalities in endocrine and metabolic systems

Adult T-cell leukaemia (ATL) is a unique type of T-cell malignancy closely associated with human T-cell leukaemia virus-1 (HTLV-1). Despite frequent descriptions of hypercalcaemia, cases accompanied by diabetes insipidus or syndrome of inappropriate secretion of anti-diuretic hormone (SIADH) in ATL patients have rarely been reported. We present an unusual case of ATL with various abnormalities in his endocrine and metabolic systems involving anterior pituitary function, thyroid function, lipid metabolism and Ca metabolism. Some of these abnormalities were considered to arise from infiltration or leukaemic cells into systemic organs after elimination of the above symptoms. Clinical and haematological data showing improvement following chemotherapy are also presented.

[An experimental study of diode laser photocoagulation and indocyanine green dye-enhanced diode laser photocoagulation in the primate retina]

A diode laser, emitting light in the near-infrared range (803 nm), was used for photocoagulation at mild, moderate, and strong intensities with or without intravenous administration of indocyanine green (ICG) in 7 eyes of 4 rhesus monkeys. The retinochoroidal lesions were studied histopathologically from 24 hours to 3 months after treatment, and choroidal vascular casts were studied by electron microscopy. Mild diode laser burns caused occlusion of the choriocapillaris and slight outer retinal damage. Moderate and severe burns caused more marked occlusion of the choriocapillaris, deep choroidal vessels, and choroidal nerves. There was little difference between ICG-enhanced and non-enhanced mild burns, but ICG-enhanced moderate and severe burns showed larger retinochoroidal lesions and more complete obstruction of the choriocapillaris than did burns without ICG enhancement. It seems that at moderate and strong levels, ICG-enhanced diode laser burns have more apparent effect on the retina and choroid, particularly on the choroidal vessels.

Restriction fragments homologous to mitochondrial plasmid-like DNAs are located within limited chromosomal regions on the rice nuclear genome

The chromosomal locations of restriction fragments of nuclear DNA that were homologous to four mitochondrial plasmid-like DNAs, namely, B1, B2, B3 and B4, were analyzed by restriction fragment length polymorphism (RFLP) analysis in cultivated rice. Nine kinds of fragments homologous to plasmidlike DNAs were analyzed for their segregation in three different F2 populations derived from intercrosses between rice subspecies; these were found to be localized in three chromosomal regions: three, one and five kinds of nuclear homologues were situated on chromosomes 1,3 and 8, respectively. Nuclear homologues on a given chromosome were tightly linked even though they were homologous to different plasmid-like DNAs. The loci of nuclear homologues found commonly in two or three cultivars were found to be highly conserved, a result that is consistent with their stable transmission. These results and those of the Southern analysis suggest the independent integration of these sequences during the varietal differentiation of rice. The concentration of loci for nuclear homologues on chromosomes 1 and 8 suggests that these sequences were integrated non-randomly into these chromosomal regions.

Transformation of the acidophilic heterotroph Acidiphilium facilis by electroporation

We constructed a cloning vector for use in the acidophilic heterotroph Acidiphilium facilis. The vector pAH101 (8.8 kb) was constructed from a 6.1 kb restriction fragment of the Acidiphilium plasmid pAH1 and a pUC19 carrying a beta-lactamase gene. The antibiotic resistance gene was efficiently expressed in A. facilis. Several factors which influenced the transformation efficiency were optimized, resulting in a transformation efficiency of up to 3 x 10(3) transformants per microgram of plasmid DNA at a field strength of 10 kV/cm with a 7.0 ms pulse.

[Fibronectin in the chorioretinal wound after laser photocoagulation]

Fibronectin (Fn) is a glycoprotein which mediates adhesion, extension, migration, and chemotaxis of the cells. We did a histochemical study of the time course of appearance and distribution of Fn in the chorioretinal wound after laser photocoagulation. In the normal chorioretinal tissue, Fn was detected in the internal limiting membrane, Bruch's membrane, and the endothelium of chorioretinal vessels. Shortly after laser photocoagulation, Fn appeared on Bruch's membrane and in the endothelium of choroidal vessels and choroidal stroma, and was prominent by one week after laser photocoagulation. Although Fn disappeared when wound healing was accomplished, it was still detected on Bruch's membrane one month after laser photocoagulation. These findings suggest that Fn is related to chorioretinal wound healing after laser photocoagulation.

Sequence variation, differential expression and chromosomal location of rice chitinase genes

Rice chitinases are encoded by a small multigene family. To clarify the overall organization of rice chitinase genes, we have isolated and characterized the genes Cht-1, Cht-2 and Cht-3. Although all the three genes encode class I chitinase, the nucleotide sequences of the coding regions of Cht-1 and Cht-3 are very similar (90%), while that of Cht-2 is clearly more divergent (78%). Only Cht-2 has a 130 bp intron and encodes a C-terminal peptide sequence similar to that known to function as a vacuolar targeting signal. In 5' flanking regions of Cht-1 and Cht-3, but not of Cht-2, conserved sequences (GGCCGGCYGCCCYAG) were found. Related sequences were found also in the 5' flanking regions of another chitinase gene and a beta-glucanase gene which has also been reported to be stress-induced in rice. RNA blot hybridization analysis demonstrated that the stress-induced expression patterns of the Cht-1 and Cht-3 genes are similar, but quite different from that of Cht-2. However, all three genes are active in unstressed roots. By restriction fragment length polymorphism (RFLP) linkage analysis, Cht-1 and Cht-3 were mapped onto chromosome 6 and shown to be closely linked (0.8 cM). Cht-2 was mapped onto chromosome 5. All these features suggest that the expression patterns of rice class I chitinase genes may be correlated with their levels of sequence divergence and their chromosomal location.

Restriction endonuclease Aor13HI from Acidiphilium organovorum 13H, a new isoschizomer of BspMII: purification and characterization

A restriction endonuclease, Aor13HI, an isoschizomer of BspMII, was purified to homogeneity from cell extracts of Acidiphilium organovorum strain 13H. The enzyme has a molecular mass of 60,000 daltons and consists of two subunits identical in molecular mass of 30,000 daltons. Aor13HI endonuclease, like BspMII, recognizes the palindromic six-base sequence 5'-TCCGGA-3', and cleaves between the T and C to produce a four-base 5' extension. Aor13HI is not inhibited by dam-dependent methylation. The isoelectric point of the enzyme is 5.7. Aor13HI activity was maximum at pH 7.5, 100 mM KCl, 7.5-10 mM MgCl2, and 55 degrees C. The enzyme was stable up to 60 degrees C. The N-terminal amino acid sequence (30 residues) of Aor13HI did not show any similarity with the sequence of other restriction endonucleases reported.

Alignment of molecular and classical linkage maps of rice, Oryza sativa

Application of genetic linkage maps in plant genetics and breeding can be greatly facilitated by integrating the available classical and molecular genetic linkage maps. In rice, Oryza sativa L., the classical linkage map includes about 300 genes which correspond to various important morphological, physiological, biochemical and agronomic characteristics. The molecular maps consist of more than 500 DNA markers which cover most of the genome within relatively short intervals. Little effort has been made to integrate these two genetic maps. In this paper we report preliminary results of an ongoing research project aimed at the complete integration and alignment of the two linkage maps of rice. Six different F2 populations segregating for various phenotypic and RFLP markers were used and a total of 12 morphological and physiological markers (Table 1) were mapped onto our recently constructed molecular map. Six linkage groups (i.e., chr. 1, 3, 7, 9, 11 and 12) on our RFLP map were aligned with the corresponding linkage groups on the classical map, and the previous alignment for chromosome 6 was further confirmed by RFLP mapping of an additional physiological marker on this chromosome. Results from this study, combined with our previous results, indicate that, for most chromosomes in rice, the RFLP map encompasses the classical map. The usefulness of an integrated genetic linkage map for rice genetics and breeding is discussed.

[A case of interstitial pneumonia of polymyositis-dermatomyositis with various pathological findings in open lung biopsy]

A 60-year-old woman was admitted to our hospital with a two month history of dry cough and dyspnea on exertion. A chest roentgenogram revealed diffuse interstitial shadows with a reduction of lower lung volume. Laboratory examinations revealed an increase in CPK and aldolase. There was decreased proximal muscle power, and the findings of a biopsy of the right deltoid were compatible with polymyositis. Myositic symptoms were stable, but the respiratory symptoms worsened, and an open lung biopsy was performed for diagnosis and to determine the best treatment. The histological findings of biopsy materials demonstrated active interstitial pneumonia complicated by cellular interstitial pneumonia, bronchiolitis obliterans organizing pneumonia, usual interstitial pneumonia and lymphoid hyperplasia. The patient responded well to adrenocorticosteroid and immunosuppressive therapy, and is now attending as an out patient. It is well known that PM-DM can be associated with interstitial pneumonia, and this complication is an important prognostic factor clinically. The pathological patterns of interstitial pneumonia in PM-DM may be divided into usual interstitial pneumonia and bronchiolitis obliterans organizing pneumonia. Furthermore, it is well documented that these patterns are concurrent with the response to adrenocorticosteroid and prognostic factors. However, our case of PM-DM, in which various patterns such as rheumatoid arthritis (RA) were pathologically revealed, cannot be considered as having uniform pathological pattern. We consider that pulmonary pathological patterns of PM-DM are very varied, as with RA. It is a very important to evaluate the nature of these patterns and the subsequent clinical course in PM-DM with interstitial pneumonia.

Isolation and Characterization of a Mo 6+ -Reducing Bacterium

A Mo 6+ -reducing bacterium (strain 48), which grew on medium supplemented with 200 mM Mo 6+ , was isolated from stream water obtained from Chengkau, Malaysia. The chemical properties of strain 48 conform to the characteristics of Enterobacter cloacae . Under anaerobic conditions in the glucose-yeast extract medium containing phosphate ion (2.9 mM) and Mo 6+ (10 mM), the bacterium reduced Mo 6+ to form molybdenum blue. Approximately 27% of Mo 6+ added to the medium was reduced after 28 h of cultivation. The reduction of Mo 6+ with glucose as an electron donor was strongly inhibited by iodoacetic acid, sodium fluoride, and sodium cyanide, suggesting an involvement of the glycolytic pathway and electron transport in Mo 6+ reduction. NADH and N,N,N′,N′ -tetramethyl- p -phenylenediamine served as electron donors for Mo 6+ reduction. When NADH was used as an electron donor, at first cytochrome b in the cell extract was reduced, and then molybdenum blue was formed. Sodium cyanide strongly inhibited Mo 6+ reduction by NADH (5 mM) but not the reduction of cytochrome b in the cell extract, suggesting that the reduced component of the electron transport system after cytochrome b serves as an electron donor for Mo 6+ reduction. Both ferric and stannous ions strongly enhanced the activity of Mo 6+ reduction by NADH.

[The effect of corticosteroid on the repair of the retinal pigment epithelium]

The effect of corticosteroid on the repairing process of the retinal pigment epithelial cells (RPE) after laser photocoagulation was investigated. Mild-intensity krypton red laser photocoagulations were performed on the monkey retina. After laser photocoagulations, betamethasone (0.5 mg/kg) were administered intramuscularly every day for 1-14 days. Moreover, the same doses of betamethasone were also administered intramuscularly for one week from the 1st to 7th day after laser photocoagulation on other monkeys. The photocoagulated lesions were observed with light and transmission electron microscopy. In monkeys that received corticosteroids, the migration and the proliferation of RPE were markedly inhibited, and the metaplasia to fibroblast-like cells of RPE was not observed. These results showed that large doses of corticosteroid inhibited the repair process of the injured RPE.

[A case of hypersensitivity pneumonitis in Pholiota nameko's manufacturer]

A 58-year-old female was admitted to our hospital because of fever and dyspnea on exertion. She has been working in the factory making Pholiota nameko for 8 years. Her chest X-ray revealed diffuse linear and fine nodular shadows in both lower lung fields. Hypoxemia was seen on blood gas analysis. Bronchoalveolar lavage (BAL) and transbronchial lung biopsy (TBLB) were performed. Differential cell count of the BAL fluid showed lymphocytosis and CD4/8 was decreased. TBLB specimens revealed bronchioloalveolitis. Precipitins against Trichosporon cutaneum were detected by Ouchterlony method. These findings are compatible with hypersensitivity pneumonitis, and Trichosporon cutaneum may have been causative antigen in this case. Trichosporon cutaneum is often detected in the Japanese summer-type hypersensitivity pneumonitis. This case suggests that Trichosporon cutaneum is one cause of hypersensitivity pneumonitis in workers at factories making Pholiota nameko.

[Detection and identification of tuberculosis by amplification of mycobacterial DNA from clinical cultured samples]

We examined 57 cultured mycobacteria using a method based on polymerase chain reaction (PCR), slot blot hybridization and dideoxy sequencing of nucleotides for detection of M. tuberculosis. Using standard microbiological tests, 34 of 57 specimens were identified as M. tuberculosis and the rest as atypical mycobacteria. Two of 34 specimens that contained M. tuberculosis were not hybridized with a probe specific for M. tuberculosis. These two specimens were identified as atypical mycobacterium by nucleotide sequencing. An atypical mycobacterium specimen that was hybridized with a prove specific for M. tuberculosis was identified as M. tuberculosis using nucleotide sequencing. These results suggest that the approach using PCR and slot blot hybridization for detection of mycobacterium may be more accurate than standard microbiological tests in the rapid and definitive diagnosis of mycobacterial infection.

[A new technique for evaluating the respiratory tract--digital subtraction bronchography (DSBG)]

Bronchography is essential for evaluation of morphological changes in the bronchial tree. However, conventional bronchography using Propyliodone (Dionosil) is extremely invasive, especially to those with pulmonary infections. In the present study, we developed a new less invasive method of bronchography with the aid of digital subtraction technique (DSBG), and evaluated its clinical benefits. Bronchography was performed by injecting contrast medium (Iopamidol: Iopamiron 300) via the lumen of the bronchoscope (Olympus Type 20), and image processing of the respiratory tract was performed using digital subtraction technique. From 1991 to 1992, DSBG was performed in 15 cases (8 bronchiectasis, 1 diffuse panbronchiolitis, 1 lung cancer, 1 pulmonary emphysema, and 4 others). DSBG clearly demonstrated the morphological changes of large and segmental bronchial lesions in cases of bronchiectasis and lung cancer, as well as conventional bronchography using Dionosil. In addition, it was possible to image the morphological changes of bronchiolar lesions in diffuse panbronchiolitis and pulmonary emphysema to the same detail as obtained using classical selective alveolo-bronchography (SAB). Since DSBG can provide enhanced images the bronchial tree without being affected by cardiac and respiratory movements, we could obtain detailed information on bronchial and/or bronchiolar lesions. With respect to side effects, Iopamiron was quickly drained and/or absorbed within 2 hours after injection. Pulmonary infection and bronchial bleeding, which are well known primary complications of classical bronchography using Dionosil, were not observed. We conclude that 1) DSBG is useful new technique for examining morphological changes of the respiratory tract, and 2) DSBG is less invasive than conventional bronchography.

Synoptometer analysis of vertical shoot in Duane's retraction syndrome

Vertical deviation of the affected eye caused by horizontal change of gaze was measured with a synoptometer in 5 cases of Duane's retraction syndrome type III. Step-by-step measurement clearly showed two types of incomitance patterns, i.e. upshoot and up- and downshoot in adduction. The former suggests a paradoxical synergistic innervation between the medial rectus and superior rectus muscles, and the latter suggests an abnormal vertical movement of the lateral rectus muscle over the globe on elevation or depression of the eye. Recession of the lateral rectus muscle, however, reduced the vertical deviation regardless of the incomitance pattern.

AcpI, a novel isoschizomer of AsuII from Acidiphilium cryptum 25H, recognizes the sequence 5'TT decreases CGAA3'

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Linkage analysis of the nuclear homologues of mitochondrial plasmid-like DNAs in rice

A genetical study on the nucleotide sequences of the nuclear DNAs which share homology with rice mitochondrial plasmid-like DNAs, B1, B2, B3 and B4 was carried out. Restriction fragments of the nuclear DNAs hybridized with these plasmid-like DNAs showed polymorphisms in their length between Indica and Japonica rice cultivars. The hybridized signals found specifically in Indica or Japonica cultivars segregated in the F2 population derived from a cross between these two subspecies. The observed ratio of the nuclear homologues in the F2 population demonstrated that they were transmitted according to the Mendelian inheritance. The co-segregation of homologues was examined and the linkage was detected between the B1-nuclear homologue of Japonica and the B4-nuclear homologue of Indica, and also between the nuclear homologues of B2 and B3 of Indica. The linkage between the B1-nuclear homologue of Japonica and the B4-nuclear homologue of Indica was conserved in the different rice cultivars.

RFLP analysis of nuclear DNAs homologous with mitochondrial plasmid-like DNAs in cultivated rice

B1 and B2 are small, circular, mitochondrial plasmid-like DNAs found in male-sterile cytoplasm (cms-Bo) of rice. In this study, nuclear sequences homologous to these DNAs were investigated among a number of rice cultivars. Several copies of nuclear B1-and B2-homologous sequences were detected in all examined cultivars, regardless of the presence or absence of the B1 and B2 DNAs in mitochondria, indicating that the existence of the B1- and B2-homologous sequences in the rice nuclear genome was widespread. A restriction fragment length polymorphism (RFLP) was detected for both sequences, and we propose that these DNAs could be useful RFLP markers for the rice nuclear genome. To analyze these nuclear homologues genetically, segregation analysis of the RFLP was carried out in the F2 progenies of an Indica-Japonica rice hybrid. Of the B1 homologues, there were two nonallelic fragments, one specific to the Indica parent and the other to the Japonica. These results indicate that the B1 and B2 homologues were dispersed in the nuclear genome. The integration of B1-homologous DNA into the nuclear DNA may have occurred independently after sexual isolation of the Indica and Japonica rice varietal groups, or a intranuclear transposition of these sequences took place during the process of rice differentiation into the varietal groups.

[The effect of trabeculotomy on the day-time variation of intraocular pressure of the primary open-angle glaucoma]

We selected 34 eyes with primary open-angle glaucoma cases having glaucomatous visual field loss, but with relatively low base-line intraocular pressure (average intraocular pressure at normal office hour, below 20mmHg) and with one or more episodes of intraocular pressure over 21mmHg in a diurnal fluctuation estimated at 8:30, 9:30, 11:30, 13:30, 15:00 and 17:00. They were treated with trabeculotomy ab externo and we compared the pre- and postoperative diurnal fluctuation pattern of the intraocular pressure. The mean of the base-line intraocular pressure decreased from 18.4 to 16.3mmHg. The mean values of the maximal pressure of the diurnal estimation and of the diurnal difference (maximum minus minimum) also decreased, from 23.4 to 17.9 and from 7.4 to 3.9mmHg, respectively. In 31 eyes (91%) the individual maximal value did not exceed 20mmHg postoperatively. From these findings, it was speculated that trabeculotomy can be effective on primary open-angle glaucoma with relatively low intraocular pressure.

[Detection of destruction of anionic sites in the outer blood-retinal barrier and damage caused by iron]

We studied the alteration of the anionic charge in the outer blood-retinal barrier in ocular siderosis by electron microscopy using the cationic probe, polyethyleneimine (PEI). The eyes of four days after injection of iron powder and control rabbit eyes demonstrated numerous PEI-positive sites at the basement membrane of the retinal pigment epithelium, collagen fiber of Bruch's membrane, and the basement membrane of the choriocapillaris. Seven days after injection of iron powder, no change was observed in the retina by light microscopy, but PEI positive sites at the basement membrane of the retinal pigment epithelium were decreased. At 14 days, it was seen that the outer layer of the retina disappeared and was replaced by pigment containing macrophages and Müller cells. Berlin blue reaction became positive in some of those macrophages and retinal pigment epithelia. PEI positive sites decreased. At 28 days, the retina was completely disorganized, and became thin, while the retinal pigment epithelium proliferated and became double layered. Berlin blue reaction was strongly positive in pigment-laden macrophages and retinal pigment epithelium. PEI-positive sites became scarce. As a result of these methods, anionic sites decreased, despite negative iron reaction of 7 days after injection of iron powder. It was shown that in ocular siderosis at an early stage, the barrier function of anionic sites between choroid and retina decreased before histological change.

Isolation and identification of restriction endonuclease Asp35HI from Acidiphilium species 35H

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[Destruction of anionic sites in blood-retinal barrier after retinal photocoagulation]

The retinal pigment epithelial cells (RPE) have "tight junctions" at the apical side of the lateral wall between neighbouring cells and form physiological blood-retinal barriers. Recently, in addition to physiological barriers, charged barriers, consisting of anionic sites of cell membrane and its basement membrane, have been discussed. We performed weak retinal photocoagulation in rabbit eyes in order to break their charged barriers, and examined the repair process using a cationic probe, polyethyleneimine (PEI). Two days after photocoagulation, RPE cells were broken down and choriocapillaries were occluded with thrombi, and their anionic sites were lost. At one week after photocoagulation, structural reconstruction started from the edge of the photocoagulation area. In this area, proliferated RPE cells covered Bruch's membrane, but their charged barrier did not recover. Two weeks after photocoagulation, proliferated RPE cells covered Bruch's membrane over the entire photocoagulated area, and they obtained anionic charge. The present study revealed that retinal damage induced by weak laser photocoagulation was repaired within two weeks after photocoagulation with respect to the charged barrier.