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1.  Properties and electron transfer specificity of copper proteins from the denitrifier "Achromobacter cycloclastes". 
Journal of Bacteriology  1986;166(2):604-608.
A blue copper protein (Mr 12,000) was purified from cells of "Achromobacter cycloclastes" grown as a denitrifier. When reduced, the blue copper protein transferred electrons to the copper protein nitrite reductase purified from the same cells, whereas a variety of cytochromes from denitrifiers failed to do so. Inclusion of a protease inhibitor, phenylmethylsulfonyl fluoride, in the buffers employed during preparation yielded purified blue copper protein with 18 more amino acid residues and two times more specific enzyme activity than other researchers have found.
PMCID: PMC214647  PMID: 3700338
2.  Axial heterogeneity of bicarbonate, chloride, and water transport in the rat proximal convoluted tubule. Effects of change in luminal flow rate and of alkalemia. 
Journal of Clinical Investigation  1986;78(6):1547-1557.
These studies examined regulation of superficial proximal convoluted tubule (PCT) transport as a function of length. When single nephron glomerular filtration rate (SNGFR) increased from 28.7 +/- 0.7 nl/min in hydropenia to 41.5 +/- 0.4 nl/min in euvolemia, bicarbonate, chloride, and water reabsorption in the early (1st mm) PCT increased proportionally: from 354 +/- 21 peq/mm X min, 206 +/- 55 peq/mm X min, and 5.9 +/- 0.4 nl/mm X min to 520 +/- 12 peq/mm X min, 585 +/- 21 peq/mm X min, and 10.1 +/- 0.4 nl/mm X min, respectively. These high transport rates did not increase further, however, when SNGFR went to 51.2 +/- 0.7 or 50.7 +/- 0.6 nl/min after atrial natriuretic factor or glucagon administration. Anion and water transport rates in the late PCT were lower and exhibited less flow dependence. During chronic metabolic alkalosis, acidification was inhibited in the late but not early PCT. In conclusion, the early PCT is distinguished from the late PCT by having high-capacity, flow-responsive but saturable, anion- and water-reabsorptive processes relatively unaffected by alkalemia.
PMCID: PMC423915  PMID: 3782470
3.  Cloning and regulation of Erwinia herbicola pigment genes. 
Journal of Bacteriology  1986;168(2):607-612.
The genes coding for yellow pigment production in Erwinia herbicola Eho10 (ATCC 39368) were cloned and localized to a 12.4-kilobase (kb) chromosomal fragment. A 2.3-kb AvaI deletion in the cloned fragment resulted in the production of a pink-yellow pigment, a possible precursor of the yellow pigment. Production of yellow pigment in both E. herbicola Eho10 and pigmented Escherichia coli clones was inhibited by glucose. When the pigment genes were transformed into a cya (adenylate cyclase) E. coli mutant, no expression was observed unless exogenous cyclic AMP was provided, which suggests that cyclic AMP is involved in the regulation of pigment gene expression. In E. coli minicells, the 12.4-kb fragment specified the synthesis of at least seven polypeptides. The 2.3-kb AvaI deletion resulted in the loss of a 37K polypeptide and the appearance of a polypeptide of 40 kilodaltons (40K polypeptide). The synthesis of the 37K polypeptide, which appears to be required for yellow pigment production, was not repressed by the presence of glucose in the culture medium, as was the synthesis of other polypeptides specified by the 12.4-kb fragment, suggesting that there are at least two types of gene regulation involved in yellow pigment synthesis. DNA hybridization studies indicated that different yellow pigment genes exist among different E. herbicola strains. None of six pigmented plant pathogenic bacteria examined, Agrobacterium tumefaciens C58, Cornyebacterium flaccumfaciens 1D2, Erwinia rubrifaciens 6D364, Pseudomonas syringae ATCC 19310, Xanthomonas campestris 25D11, and "Xanthomonas oryzae" 17D54, exhibited homology with the cloned pigment genes.
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PMCID: PMC213523  PMID: 3023282
4.  Bacterial and mycotic otological infections in Singapore. 
The Journal of Hygiene  1986;97(2):385-392.
This paper describes a microbiological study of 84 young adult men with clinical otitic infections. Gram-negative aerobic bacilli were frequently isolated from these patients diagnosed as having otitis externa or chronic suppurative otitis media, of which Pseudomonas species predominated. Staphylococcus aureus, S. epidermidis and aerobic Corynebacterium species (diphtheroids) were also found. About 40% of ear infections were attributed to otomycoses, chiefly from Aspergillus species and Candida parapsilosis. Antimicrobial susceptibility testing of the bacterial isolates revealed that Pseudomonas species were generally resistant to antibiotics commonly employed in general practice: ampicillin, erythromycin, co-trimoxazole, tetracycline and cephaloridine. However, polymyxin B, gentamicin and neomycin were active against some Pseudomonas isolates. Other Gram-negative bacilli were also mainly sensitive to gentamicin, neomycin as well as co-trimoxazole. Disc diffusion and minimum inhibitory concentration studies demonstrated good activity of ceftazidime, cefoperazone, tobramycin and carbenicillin against strains of Pseudomonas species and other Gram-negative rods. Cefotaxime and cefoxitin were active against Gram-negative bacilli other than Pseudomonas species. Beta-lactamase production did not appear to be the main mechanism of resistance in these community-acquired Gram-negative bacillary isolates. The antimicrobial therapy of otological infections is reviewed.
PMCID: PMC2083530  PMID: 3782787
6.  Clonal origins of lymphoproliferative disease induced by Epstein-Barr virus. 
Journal of Virology  1986;58(3):975-978.
Analysis of immunoglobulin gene rearrangements in 16 B-cell lineages clonally propagated from two mononucleosis patients supported the notion that mononucleosis is a polyclonal B-lymphoproliferative disorder. Three of seven cell clones from a patient with a fatal B lymphoma revealed the same pattern of immunoglobulin gene rearrangement, indicating that this patient's disease was oligoclonal. The three similar clones were propagated from two sites (blood and spleen), indicating that they represent a metastatic cell lineage which arose during the patient's fatal B lymphoproliferation.
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PMCID: PMC253010  PMID: 3701935
7.  In vivo localization of DNA topoisomerase II cleavage sites on Drosophila heat shock chromatin. 
Molecular and Cellular Biology  1986;6(4):985-992.
Similar to its inhibitory effect on mammalian DNA topoisomerase II, the cytotoxic drug VM26 (teniposide) also interferes with the breakage-reunion reaction of Drosophila melanogaster DNA topoisomerase II. VM26 induces topoisomerase II-mediated DNA breakage in vitro and in cultured D. melanogaster cells presumably by stabilizing an enzyme-DNA cleavable complex. The drug-induced DNA breaks on D. melanogaster hsp70 genes were mapped in cultured cells using the indirect end-labeling procedure. Multiple and specific cleavage sites occurred at both the 3' and 5' ends of the hsp70 genes. A number of these cellular topoisomerase II cleavage sites mapped close to the DNase I-hypersensitive regions of the hsp70 genes. The intensities of several topoisomerase II cleavage sites changed significantly on heat shock induction. Treatment of cultured D. melanogaster cells with VM26 at 25 degrees C resulted in the stimulation of transcription of the hsp70 genes. These results suggest that inhibition of DNA topoisomerase II may lead to heat shock transcription.
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PMCID: PMC367606  PMID: 3023886
8.  Isolation and sequence analysis of the gene (cpdB) encoding periplasmic 2',3'-cyclic phosphodiesterase. 
Journal of Bacteriology  1986;165(3):1002-1010.
The cpdB gene encodes a periplasmic 2',3'-cyclic phosphodiesterase (3'-nucleotidase). This enzyme has been purified previously and the gene is located at 96 min on the Escherichia coli chromosome. In this study the cpdB gene was cloned from ClaI-cleaved DNA, and the gene product was identified. DNA blotting experiments showed that the recombinant plasmid contains a deletion with respect to the expected genomic fragment of approximately 4 kilobases, which extends into the vector. Furthermore, the gene was absent from three other recombinant libraries. Together, these findings suggest the presence in the genome of an adjacent gene whose product is lethal when it is present on a multicopy plasmid. The nucleotide sequence of the cpdB gene was also determined. The 5' and 3' untranslated sequences contain characteristic sequences that are involved in the initiation and termination of transcription, including two possible promoters, one of which may contain two overlapping -10 sequences. A strong Shine-Dalgarno sequence is followed by an open reading frame which corresponds to a protein having a molecular weight of 70,954. The first 19 amino acid residues have the characteristics of a signal peptide. The 3' untranslated sequence contains two putative rho-independent transcription terminators having low thermodynamic stability.
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PMCID: PMC214528  PMID: 3005231
9.  Effects of 2,2'-O-cyclocytidine and acyclovir on latent herpes simplex virus in trigeminal ganglia of mice. 
The effects of 2,2'-O-cyclocytidine (CC) and acyclovir (ACV) on latent herpes simplex virus (HSV) in trigeminal ganglia were studied in an in vitro model using reactivation of HSV type 1 (HSV-1) as a model. It was shown that both CC (10 micrograms/ml) and ACV (2.5 micrograms/ml) significantly inhibited the reactivation of the latent HSV-1 in infected ganglia. The effect of CC (25 micrograms/ml), which was as good as that of ACV (10 micrograms/ml), did not last as long as that of ACV after removal of the drugs. The latent state of HSV-1 in vitro was dependent on the continuous presence of either drug. Even though the latent HSV-1 could not be eliminated completely from the trigeminal ganglia by discontinuous administration of either drug, its titers were markedly reduced. The combination of CC and ACV had a synergistic effect on preventing the reactivation of the latent HSV-1 in vitro.
PMCID: PMC176390  PMID: 2424367
10.  Amiodarone pulmonary toxicity: functional and ultrastructural evaluation. 
Thorax  1986;41(2):100-105.
Pulmonary function, chest radiographic appearances, and the cellular composition of bronchoalveolar lavage fluid were assessed in 13 patients who were receiving amiodarone treatment. Eight of the patients had developed clinical and radiological evidence of lung disease and five were symptom free. The proportions of lymphocytes (mean 8.6 (SD 6.9)) and neutrophils (mean 3.4 (3.3)) obtained by bronchoalveolar lavage were similar in patients with and without lung complications. Electron microscopic examination of alveolar macrophages showed intralysosomal inclusion bodies in all subjects, regardless of clinical state. There was no significant difference in the mean number of inclusion bodies per macrophage transection between those with and those without lung disease. The differential cell count in bronchoalveolar lavage fluid and the presence of macrophage inclusion bodies were therefore not useful as markers of disease activity. Among those who developed clinical and radiological evidence of lung disease, the cumulative drug dose per kilogram of body weight and the duration of treatment (mean 16.5 (SD 9.0) months) were significantly correlated with the degree of lung restriction as measured by total lung capacity and forced vital capacity. It is concluded that, while the severity of the restrictive pulmonary defect that is induced by amiodarone is largely dose related, the development of lung toxicity is to some extent idiosyncratic.
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PMCID: PMC460270  PMID: 3010484
11.  Intussusception--current trends in management. 
Barium enema reductions were attempted in 65 (90%) of 72 intussusceptions, of which 51 (79%) were successful. This represents a success rate of 70% overall. The average hospital stay was 3 1/2 days. There was no mortality and, apart from a recurrence rate of 10%, no morbidity. It is suggested that barium enema reduction should be the treatment of choice provided that there is an emergency service of a paediatric radiologist and the patient is adequately resuscitated, the only absolute contraindication being evidence of pneumatosis intestinalis or peritonitis. Those patients who presented with shock, rectal bleeding, duration of symptoms longer than 48 hours, and pronounced degree of bowel obstruction had a higher rate of unsuccessful reduction. However, only the last two were significant. Further, provided that the clinical condition remains satisfactory and the reduction has been achieved to the caecum a repeat barium enema after some hours may be successful in achieving reflux of contrast into the ileum, confirming complete reduction.
PMCID: PMC1777532  PMID: 3954422
12.  The role of metaphosphate in the activation of the nucleotide by TPS and DCC in the oligonucleotide synthesis. 
Nucleic Acids Research  1986;14(6):2699-2706.
The course of the activation of 3'-acetylthymidine 5'-phosphate by TPS and DCC were followed up by 31P FT nmr. The fact that the "metaphosphate" (delta-5.1) first becomes detectable only at later stage of the activation and does coexist with pyrophosphate and triphosphate suggests that the pyridinium derivative of "metaphosphate" is most probably not directly formed from the hypothetical mixed anhydride or active "pseudourea" right at the beginning of the reaction of pdTac with TPS or DCC, but rather formed at later stage of the activation reaction from the degradation of the pyro- and triphosphates by the activating agent. The mixed anhydride or the active "pseudourea" is most possibly the active key intermediate.
PMCID: PMC339692  PMID: 3754328
13.  Variable effects of DNA-synthesis inhibitors upon DNA methylation in mammalian cells. 
Nucleic Acids Research  1986;14(10):4353-4367.
Post-synthetic enzymatic hypermethylation of DNA was induced in hamster fibrosarcoma cells by the DNA synthesis inhibitors cytosine arabinoside, hydroxyurea and aphidicolin. This effect required direct inhibition of DNA polymerase alpha or reduction in deoxynucleotide pools and was not specific to a single cell type. At equivalently reduced levels of DNA synthesis, neither cycloheximide, actinomycin D nor serum deprivation affected DNA methylation in this way. The topoisomerase inhibitors nalidixic acid and novobiocin caused significant hypomethylation indicating that increased 5-mCyt content was not a necessary consequence of DNA synthesis inhibition. The induced hypermethylation occurred predominantly in that fraction of the DNA synthesized in the presence of inhibitor; was stable in the absence of drug; was most prominent in low molecular weight DNA representing sites of initiated but incomplete DNA synthesis; and occurred primarily within CpG dinucleotides, although other dinucleotides were overmethylated as well. Drug-induced CpG hypermethylation may be capable of silencing genes, an effect which may be relevant to the aberrantly expressed genes characteristic of neoplastic cells.
PMCID: PMC339866  PMID: 3086840

Results 1-13 (13)