Application of the variable region in 16S rDNA to create an index for rapid species identification in the genus Streptomyces

Partial nucleotide sequences (120 bp) of the 16S rRNA gene (rDNA) containing a variable alpha region were compared in 89 strains of the genus Streptomyces belonging to eight major clusters of category I in Bergey's Manual of Systematic Bacteriology. Fifty-seven kinds of partial 16S rDNA sequences were observed among the 89 strains. Forty-three of the strains were grouped into 11 'identity groups', based on the fact that the strains in each group shared an identical sequence in the 120-bp region. The results of a phylogenetic analysis based on the 16S rDNA 120-bp sequences revealed that 60 of the 89 strains could be categorized into seven clusters, each consisting of four or more strains. Based on these observations it was concluded that short nucleotide sequences bearing the variable alpha region are useful for Streptomyces species identification.

Percutaneous microwave coagulation therapy for solitary metastatic liver tumors from colorectal cancer: a pilot clinical study

OBJECTIVE

Percutaneous microwave coagulation therapy (PMCT) was performed for metachronous small solitary liver tumors measuring < or = 3.0 cm in diameter that had metastasized from colorectal cancer. PMCT was used for local control of the lesions, and the efficacy of this treatment was assessed.

METHODS

In 15 patients, a microwave electrode (specially designed for this purpose, 25 cm long and 2.0 mm thick) was inserted percutaneously into the tumor area under ultrasonic guidance. Microwaves at 80 watts were used to irradiate the tumor and the surrounding area.

RESULTS

Thirteen of the 15 metastatic tumors were radically ablated by 3-10 applications of microwave irradiation. Although the follow-up period was short (9-37 months), 10 patients survived. No recurrence has been detected in the treated area (except two foci where PMCT was insufficient), and no serious side effects or complications were encountered during or after the PMCT. In four of the five nonsurviving patients, death was due to metastases to the bone, brain, lung, or other areas of the liver despite complete local tumor control by PMCT.

CONCLUSION

PMCT is a safe and effective treatment for metachronous small liver tumors that have metastasized from colorectal cancer.

Construction of lactose-assimilating and high-ethanol-producing yeasts by protoplast fusion

The availability of a yeast strain which is capable of fermenting lactose and at the same time is tolerant to high concentrations of ethanol would be useful for the production of ethanol from lactose. Kluyveromyces fragilis is capable of fermenting lactose, but it is not as tolerant as Saccharomyces cerevisiae to high concentrations of ethanol. In this study, we have used the protoplast fusion technique to construct hybrids between auxotrophic strains of S. cerevisiae having high ethanol tolerance and an auxotrophic strain of lactose-fermenting K. fragilis isolated by ethyl methanesulfonate mutagenesis. The fusants obtained were prototrophic and capable of assimilating lactose and producing ethanol in excess of 13% (vol/vol). The complementation frequency of fusion was about 0.7%. Formation of fusants was confirmed by the increased amount of chromosomal DNA per cell. Fusants contained 8 x 10 to 16 x 10 mug of DNA per cell as compared with about 4 x 10 mug of DNA per cell for the parental strains, suggesting that multiple fusions had taken place.

Isolation of xylose reductase gene of Pichia stipitis and its expression in Saccharomyces cerevisiae

A NADPH/NADH-dependent xylose reductase gene was isolated from the xylose-assimilating yeast, Pichia stipitis. DNA sequence analysis showed that the gene consists of 951 bp. The gene introduced in Saccharomyces cerevisiae was transcribed to mRNA, and a considerable amount of enzyme activity was observed constitutively, whereas transcription and translation in P stipitis were inducible. S. cerevisiae carrying the xylose reductase gene could not, however, grow on xylose medium, and could not produce ethanol from xylose. Since xylose uptake and accumulation of xylitol by S. cerevisiae were observed, the conversion of xylitol to xylulose seemed to be limited.

Construction of killer wine yeast strain

A double-stranded RNA plasmid which confers the superkiller phenotype was transferred into a wine yeast (Montrachet strain 522) and its leucine-requiring derivative (strain 694) by cytoduction, using the protoplast fusion technique. The killer wine yeast constructed completely suppressed the growth of killer-sensitive strains of Saccharomyces cerevisiae in yeast extract-peptone-glucose medium at pH 4.5, whereas the killer effect was somewhat decreased at pH 3.5. The wine yeast harboring the killer factor also inhibited the growth of killer-sensitive cells satisfactorily when it was grown in grape juice.

Distribution of immunoreactive thyrotropin-releasing hormone in the forebrain and hypophysis of the bullfrog, Rana catesbeiana

The distribution of immunoreactive thyrotropin-releasing hormone (TRH) in the forebrain and hypophysis of Rana catesbeiana was studied by means of specific radioimmunoassay and immunohistochemistry based on peroxidase-antiperoxidase (PAP) techniques. A relatively high concentration of immunoassayable TRH is present in the hypothalamus. Immunoreactive TRH cell bodies are found in the anterior part of the preoptic nucleus, the dorsal infundibular nucleus, the nucleus of diagonal band of Broca, and the medial part of the amygdala. Immunoreactive nerve terminals are observed in the neurohypophysis and the external layer of the median eminence, where the terminals are in close contact with the capillary loops of the hypophyseal portal vessels. The possible role of TRH in the frog brain is discussed.

Distribution and ultrastructural localization of a receptor for pituitary adenylate cyclase activating polypeptide and its mRNA in the rat retina

Localization and gene expression of pituitary adenylate cyclase activating polypeptide receptor (PACAPR) in the rat retina were studied by immunocytochemistry and in situ hybridization, respectively. Antisera were raised against a synthetic peptide that corresponds to the carboxy-terminal cytoplasmic domain which is found in all subtypes of PACAPR. Strong PACAPR mRNA expression and PACAPR-like immunoreactivity (PACAPR-LI) were detected in ganglion cells, amacrine cells, and in the inner plexiform layer. PACAPR-LI appeared to be concentrated predominantly in the neuronal perikarya and processes. At the ultrastructural level, strong immunostaining for PACAPR was visible in the plasma membranes, rough endoplasmic reticulum and cytoplasmic matrix in neurons. This study provides the basis for a better understanding of the functions of PACAP in the rat retina.

Nasal absorption of zidovudine and its transport to cerebrospinal fluid in rats

The nasal absorption of zidovudine (AZT) and its subsequent transport to cerebrospinal fluid (CSF) was examined in rats. Both rapid absorption and a high CSF concentration were observed after the nasal application. Plasma and CSF concentrations of AZT increased when probenecid was coadministered with AZT. Thus, this nasal coadministration of AZT and probenecid could be useful for the treatment of AIDS patients with neuropathies.

Mechanism of skin penetration-enhancing effect by laurocapram

In order to clarify the mechanism of action of laurocapram (Azone) on the skin permeation of drugs, the following experiments were done. First, the effect of Azone on the skin components was compared with that of other penetration enhancers. Azone markedly fluidized liposomal lipids (as a model lipid system) compared with other enhancers. Ethanol extracted large amounts of the stratum corneum lipids, whereas Azone did not. These results suggest that the effect of Azone on the lipids in the stratum corneum is not the same as that of ethanol. In addition, ethanol increased the amount of free sulfhydryl (SH) group of keratin in the stratum corneum, whereas Azone did not directly affect the stratum corneum protein. Azone increased water content in the stratum corneum, as measured by skin conductance. This effect might be a reason for the action of Azone. For further understanding, the enhancing effects of Azone on the skin permeation of several model compounds (alcohols, sugars, and inorganic ions) were compared with the effects of pretreatment with distilled water, which was thought to increase water-holding capacity, and pretreatment with ethanol, which was thought to affect the lipids and protein in the skin barrier (i.e., stratum corneum). Pretreatment with water or ethanol enhanced skin permeation of hydrophilic compounds, whereas they decreased that of octanol, a hydrophobic compound. The tendency of Azone to increase or decrease the skin permeation rate of most compounds was similar to that of pretreatment with water or ethanol. However, the effect of Azone on the skin permeation of inorganic ions was relatively low, whereas that of pretreatment with water or ethanol was high.(ABSTRACT TRUNCATED AT 250 WORDS)

Nucleotide sequences of small ribosomal RNA and adjacent transfer RNA genes in rat mitochondrial DNA

The nucleotide sequences of genes for small 12 S ribosomal RNA and two transfer RNAs (tRNAPhe and tRNAVal) and their common upstream region in cloned rat mitochondrial DNA were determined. This DNA sequence of 1709 bp extends between the HindII and HindIII cleavage sites in the EcoRI-A and EcoRI-D fragments, respectively. There is no long reading frame for protein synthesis starting from the HindIII site and extending all the way to the HindII site, or vice versa. The heavy strand was found to be the template for these RNA transcripts. The 5' and 3' ends of the 12 S ribosomal RNA gene are contiguous with the tRNAPhe and tRNAVal genes, respectively. The structural features of the two tRNA genes are significantly different from the standard prokaryotic tRNA pattern. Since similar contiguous natures of these genes in human (Crews and Attardi, Cell 19 (1980) 775; Eperon et al., Nature 286 (1980) 460) and mouse (Van Etten et al., Cell 22 (1980) 157) mitochondrial DNA have been reported, comparative studies on the structures of these genes were performed by computer analysis and the characteristic features are discussed.

Investigation of the release behavior of diethylhexyl phthalate from the polyvinyl-chloride tubing for intravenous administration

The release behavior of diethylhexyl phthalate (DEHP) from a polyvinyl-chloride (PVC) tube, which is part of an intravenous administration set, was investigated with the coexistence of polysorbate 80 (Tween 80) in various solutions such as physiological saline (PS), distilled water for injection (DWI) and glucose solution (TZ). The cumulative amount of DEHP released after 5 h was in the following order; PS, DWI > 50% TZ. From a comparison of the amount of released DEHP and the critical micelle concentration (CMC) of various solutions, the lower the CMC of the solution, the higher the amount of DEHP released from the PVC tubing. When the concentration of Tween 80 was kept constant at 1 mg/ml, the cumulative amount of DEHP released with a flow rate 90 ml/h was higher than that at 60 ml/h. These results suggest that the release of DEHP from the PVC tubing is closely correlated with the interaction of Tween 80 and DEHP such as the formation of micelles, the collision of micelles against the surface of the PVC tubing and the diffusion properties of DEHP and or Tween 80 in the liquid medium.

Use of differential subtraction method to identify genes that characterize the phenotype of cultured rheumatoid arthritis synoviocytes

OBJECTIVE

To identify the genes that characterize the distinctive phenotype of cultured rheumatoid arthritis (RA) fibroblastoid synoviocytes.

METHODS

A representational difference method was used to subtract complementary DNA (cDNA) from cultured RA fibroblastoid synoviocytes with cDNA from noninflammatory osteoarthritis synoviocytes. The genes were identified by DNA sequencing, and their relative expression was determined by Northern blot analysis.

RESULTS

Twenty-four genes were identified, including novel genes such as a human homolog of mouse semaphorin E and one homologous to N-acetylglucosamine-6-sulfatase. Eleven of these genes were constitutively overexpressed in the rheumatoid synoviocyte line, including a chemokine, stromal cell-derived factor 1, and several genes capable of mediating synoviocyte-leukocyte interactions, including vascular cell adhesion molecule 1 and Mac-2 binding protein. Three genes (lumican, biglycan, and insulin-like growth factor binding protein 5) encoded extracellular matrix components, suggesting that distinct stromal-synoviocyte interactions may be mediated by this phenotype. Two interferon-inducible genes of unknown function were also found, emphasizing the presence of activation-like features in the phenotype.

CONCLUSION

A general method for the identification of differences in patterns of gene expression revealed that cultured RA fibroblastoid synoviocytes overexpress certain proinflammatory genes that are potentially relevant to lymphocyte and monocyte entry and interactions. The features of the genes identified in these mesenchymal cells suggest that they facilitate localization of immune reactions to the joint through leukocyte chemokinesis, cell-cell adhesion, and matrix specialization. The further characterization of these genes should help in resolving whether this phenotype is the consequence of modulation and imprinting by an inflammatory milieu or, more likely, whether it reflects the intrinsic lineage characteristics of intimal lining synoviocytes.

Structural organization of the rat thy-1 gene

Thy-1 is a differentiation marker expressed predominantly on thymocytes, T cells and brain tissue. Its presence on murine peripheral T cells but not B cells has long been used to distinguish between these two populations of lymphocytes. Although analogues of Thy-1 have been described in several mammalian species, its tissue distribution in different species varies widely, precluding its use as T-cell-specific marker. The Thy-1 molecule is a cell-surface glycoprotein of relative molecular mass 18,000, one-third of which represents carbohydrate; the protein moieties of the rat and murine Thy-1 molecules have been sequenced and found to consist of 111 and 112 amino acids, respectively. An unusual aspect of Thy-1 is the apparent absence of a hydrophobic segment comparable to that observed in other membrane glycoproteins which would allow integration of Thy-1 within the membrane lipid bilayer. This has prompted speculation that Thy-1 is anchored to the cell surface by some other hydrophobic component such as glycolipid. Here we report the structure of thy-1 complementary DNA and genomic clones and describe the exon-intron organization of the gene. More importantly, our data indicate that Thy-1 is initially synthesized as a molecule of 142 amino acids, 31 amino acids longer at the carboxyl end than the Thy-1 molecule isolated and characterized by Campbell et al. An extremely hydrophobic region of 20 amino acids lies within this 31-amino acid stretch and may represent the transmembrane segment responsible for anchoring Thy-1 to the cell membrane.

Differential expression of type IV collagen isoforms, alpha5(IV) and alpha6(IV) chains, in basement membranes surrounding smooth muscle cells

Smooth muscle is composed of cigar-shaped, non-striated cells, each of which is encapsulated by a basement membrane and forms the contractile portion of tubular organs such as the gastrointestinal tract, pulmonary tract, genitourinary tract, and vasculature, in which slow and sustained contractions are needed. We examined basement membranes produced by smooth muscle cells and, using alpha(IV) chain-specific monoclonal antibodies, analyzed type IV collagens in these organs. Detailed distribution analysis of the alpha chains in normal and Alport cases by use of specific antibodies indicated that there are at least three molecular forms of type IV collagen, [alpha1(IV)]2alpha2(IV),alpha3(IV)alpha4(IV)alpha5+ ++(IV), and alpha5(IV)/alpha6(IV). Smooth muscle cells in the urinary bladder and uterus were enclosed by basement membranes composed of alpha1, alpha2, alpha5, and alpha6 chains. The same alpha chains were present around smooth muscle cells in the muscular layer of the fundus of the stomach, whereas those in the antrum and further distal side of the gastrointestinal tract expressed mostly alphal and alpha2 chains. In addition, immunostaining analysis of the vasculature also showed that most of the smooth muscle cells were positive for alpha1 and alpha2 chains; however, alpha5 and alpha6 chains were also expressed by smooth muscle cells in the aorta and some arteries where blood pressure changes significantly. These results suggest that the smooth muscle cells enclosed by alpha5/alpha6-containing basement membranes might have some particular function related to mechanical stress or tensile strength during the characteristic contractile activity of tubular organs.

Angiographic demonstration of no-flow anatomical patency of internal thoracic-coronary artery bypass grafts

To clarify the no-flow situation of the stringlike internal thoracic artery graft, we angiographically examined such grafts by temporarily occluding the recipient coronary artery with a percutaneous transluminal coronary angioplasty balloon and were able to reveal anatomical patency of the internal thoracic artery graft in 2 patients 1 year and 3 years after the operations. Thus, there is a possibility that internal thoracic artery grafts may continuously maintain anatomical patency even under no-flow situations just like nonfunctioning collateral vessels and may function properly later as a graft when the native coronary flow decreases. Also, this angiographic technique can be a new method for detecting anatomical patency of no-flow and functionally closed internal thoracic artery grafts.

Angiotensin II stimulation of Ca2+-channel current in vascular smooth muscle cells is inhibited by lavendustin-A and LY-294002

Angiotensin II (AngII) is coupled to several important intracellular signaling pathways, and increases intracellular Ca2+. In vascular smooth muscle (VSM) cells, AngII is known to activate enzymes such as tyrosine protein kinase (Tyr-PK), phospholipase C (PLC), protein kinase C (PKC), and phophatidylinositol-3-kinase (PI-3-K). A non-receptor Tyr-PK, pp60(c-src), and PKC have been reported to stimulate the Ca2+ channels in VSM cells. However, less is known about AngII action on the voltage-gated Ca2+ channels. The Ca2+-channel currents of a cultured rat aortic smooth muscle cell line, A7r5, were recorded using whole-cell voltage clamp. Application of 50 nM AngII significantly increased the amplitude of Ba2+ currents through the voltage-gated Ca2+ channels (IBa) by 34. 5+/-9.1% (n=10) within 1 min. In the presence of lavendustin-A (5 microM), a selective inhibitor of Tyr-PK, AngII failed to stimulate IBa (n=5). AngII stimulation of IBa was also prevented by (5 microM) LY-294002, an inhibitor of PI-3-K (n=5). In contrast, H-7 (30 microM), an inhibitor of PKC, did not prevent the effect of AngII on IBa (n=6). These results suggest that AngII may stimulate the Ca2+ channels of VSM cells through Tyr-PK and PI-3-K under conditions that probably exclude participation of PK-C.

Apoptosis-inducing activity of lipid derivatives of gallic acid

Gallic acid derivatives with a lipophilic group (hydrogenated farnesyl gallate, lauryl gallate, gallic acid laurylamide and cholesteryl gallate) were examined for their ability to induce apoptosis in human monoblastic leukemia U937 cells. Farnesyl ester derivative is the most potent apoptosis inducer among the compounds examined. The results suggest that lipid derivatives can augment the apoptosis-inducing activity of gallic acid depending on the structure. These findings will provide useful information in developing anti-cancer agents.

Foot drop due to lumbar degenerative conditions: mechanism and prognostic factors in herniated nucleus pulposus and lumbar spinal stenosis

OBJECT

The aim of this study was to analyze the mechanism and prognostic factors of foot drop caused by lumbar degenerative conditions.

METHODS

The authors retrospectively reviewed the charts of 28 patients with foot drop due to a herniated nucleus pulposus (HNP) or lumbar spinal stenosis (LSS), scoring between 0 and 3 on manual muscle testing for the tibialis anterior muscles. They analyzed the mechanism of foot drop and whether the duration before the operation, preoperative tibialis anterior and extensor hallucis longus strength, age, gender, and diabetes mellitus were all found to be prognostic factors for postoperative tibialis anterior recovery. They also investigated whether the diagnosis had any influence on the prognosis.

RESULTS

The compression of double roots and a sequestrated fragment were observed, respectively, in 9 and 13 of 16 patients with HNP. Multiple levels including the L4-5 segment were decompressed in 8 of 12 patients with LSS. Analysis did not demonstrate any prognostic factor in surgically treated HNP, but significant associations with prognosis were observed with respect to preoperative tibialis anterior (p = 0.033) and extensor hallucis longus (p = 0.020) strength in patients with LSS. In addition, the postoperative muscle recovery in patients with HNP was significantly superior to that in patients with LSS (p = 0.011).

CONCLUSIONS

Double root compression was the most common condition associated with foot drop due to HNP. The diagnosis and preoperative tibialis anterior and extensor hallucis longus strength in LSS were factors that influenced recovery following an operation.

Expression of the Thy-1 glycoprotein gene by DNA-mediated gene transfer

We isolated a gene encoding the Thy-1.2 glycoprotein from a recombinant library constructed from BALB/c mouse DNA. To evaluate the expression of this cloned gene in different genomic environments, we introduced it into cell lines derived from fibroblast, lymphoid, and neuronal tissues by DNA-mediated gene transfer. When integrated into the genome of mouse L cells, cell-surface Thy-1 can be detected with anti-Thy-1 monoclonal antibodies. These L-cell lines contain between two and four copies of the cloned Thy-1 gene stably integrated in the host genome. After subcloning into a plasmid vector containing the bacterial Eco-gpt gene as a selectable marker, the Thy-1 gene was introduced into the Thy-1-deficient mouse lymphoma AKR1 (Thy-1-d), and the rat neuronal cell line, B50. The resulting transformants also contain two to four copies of the cloned Thy-1 gene but express up to 50-fold more cell-surface Thy-1.2 than the L cell transformants. The expression of vastly differing amounts of cell-surface Thy-1 from similar numbers of genes suggests that the gene encoding this differentiation antigen is under tissue-specific regulation.

Association of HLA-B51 and lack of association of class II alleles with Behcet's disease

Eighty-one Behcet's disease patients have been studied for HLA association by HLA-DRB1, -DQA1, -DQB1 and -DPB1 genotyping with the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique and for NcoI RFLP in the tumor-necrosis factor (TNF beta) gene by Southern hybridization in addition to serological typing. In serological typing, the frequency of HLA-B51 was significantly increased in the patients. In PCR genotyping, there was a significant increase in the HLA-DRB1*0802, DQA1*0301 and DQB1*0303 alleles, whereas the frequencies of DRB1*1502, DQA1*0103, DQA1*0101, DQB1*0601 and DQB1*0501 showed a significant decrease in the patients. No significant difference was observed in any HLA-DPB1 alleles. Among them, B51 was found to be a genetic marker most strongly associated with Behcet's disease (p less than 0.00005, chi 2 = 46.47, pc[corrected p] less than 0.005). The positive and negative associations of class II alleles with the disease can be explained by linkage disequilibrium with B51, and do not reach statistical significance by the corrected p-value test. In NcoI RFLP typing in the TNF beta gene, 250 kb centromeric of the HLA-B gene, the frequency of a 5.5 kb fragment was considerably decreased in the patients when compared to the controls, although the decrease was not statistically significant.(ABSTRACT TRUNCATED AT 250 WORDS)

Neurological manifestations of hemorrhagic colitis in the outbreak of Escherichia coli O157:H7 infection in Japan

An outbreak of hemorrhagic colitis associated with Escherichia coli O157:H7 occurred in a kindergarten in Saitama, Japan from September to November, 1990. Seven patients admitted to our hospital showed neurological manifestations: generalized seizures, impaired consciousness, urinary incontinence, gaze nystagmus, phrenic nerve palsy, action tremor and vertigo. Two patients died. On the basis of the clinical courses and laboratory findings of the seven patients and postmortem findings of one case, these neurological symptoms were suspected to be induced by the verotoxin elaborated by Escherichia coli O157:H7.

Nucleotide sequence of a cloned fragment of rat mitochondrial DNA containing the replication origin

The nucleotide sequence was determined for the 717 bp HapII subfragment (HapEcoA5) of the EcoRI-A fragment of rat mitochondrial DNA, which contains the heavy-strand replication origin. Analysis of the heavy-strand initiation segments released from the D-loop molecules has revealed that some 5'-ends of these initiation segments are linked to ribonucleotide(s) and are heterogeneous. Sequence analysis of the 5'-end portion of the initiation segment indicated that one of the start points of the deoxyribonucleotide polymerization corresponds to the 425th bp on the HapEcoA5. Two-fold rotational symmetry and palindrome structures, and a G-cluster sequence around the start point have been discussed in connection with unidirectional replication.

Calcium wave evoked by activation of endogenous or exogenously expressed receptors in Xenopus oocytes

The mRNA encoding the cloned substance K receptor was microinjected into Xenopus laevis oocytes. After expression of the mRNA, Ca2+ was imaged in the oocytes with a digital imaging fluorescence microscopy system using the Ca2(+)-sensitive dyes fura-2 and fluo-3. Application of substance K caused a dose-related wave of Ca2+ mobilization to spread from a focus and to elevate the Ca2+ concentration in the oocyte. Activation of endogenous muscarinic or angiotensin II receptors in noninjected oocytes evoked a similar response. The Ca2+ rise in oocytes induced by substance K was due to internal Ca2+ mobilization and was independent of external Ca2+, since it occurred in Ca2(+)-free medium fortified with 2 mM EGTA. The Ca2+ imaging was well correlated with ion current measurements of voltage-clamped oocytes. Imaging, in addition to detecting the spatial spread of Ca2+ across the cell, was at least as sensitive as voltage clamping and much faster when screening oocytes for the expression of receptor mRNAs that stimulate Ca2+ mobilization. While it is known that fertilization of Xenopus eggs causes a spreading wave of Ca2+ mobilization, we found that activation of either native or newly expressed receptors in oocytes causes a similar change in Ca2+ distribution.