1076
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Abe T, Tominaga Y, Kikuchi T, Watanabe A, Satoh K, Watanabe Y, Nukiwa T. Bacterial pneumonia causes augmented expression of the secretory leukoprotease inhibitor gene in the murine lung. Am J Respir Crit Care Med 1997; 156:1235-40. [PMID: 9351627 DOI: 10.1164/ajrccm.156.4.9701075] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The cDNA of murine secretory leukoprotease inhibitor (SLPI) was cloned from a mouse lung cDNA library. The amino acid sequence deduced from the cDNA showed 58 and 51% homology with those of human and porcine SLPI, respectively. A two-domain structure with similar amino acid sequences, four intradomain disulfide bonds, and high proline content, which are characteristics common to human and porcine SLPI, was also found in the mouse protein. The amino acid residues for the signal sequence and active site are also conserved in mouse SLPI. RNase protection assay showed the expression of the SLPI gene in liver, intestine, spleen, and epididymis, suggesting the distribution of SLPI in tissues other than lung and seminal vesicles. In the lung infected with Streptococcus pneumoniae strain FP1284, 10 h after inoculation of bacteria the number of SLPI mRNA transcripts was three times higher than baseline. The increased level of expression remained constant for at least 48 h. This result clearly contrasts to that obtained for spleen, in which the SLPI mRNA transcript level was mostly unchanged during the course of pneumonia. These facts suggested the local regulation of the SLPI gene expression in vivo in response to inflammatory stimuli at the site of inflammation.
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MESH Headings
- Amino Acid Sequence
- Animals
- Base Sequence
- Blotting, Northern
- Blotting, Southern
- Cells, Cultured
- DNA Probes/chemistry
- Disease Models, Animal
- Gene Expression Regulation, Enzymologic
- Humans
- Lung/enzymology
- Lung/pathology
- Male
- Mice
- Mice, Inbred C57BL
- Molecular Sequence Data
- Pneumonia, Pneumococcal/enzymology
- Pneumonia, Pneumococcal/pathology
- Polymerase Chain Reaction
- Protein Biosynthesis
- Proteinase Inhibitory Proteins, Secretory
- Proteins/genetics
- RNA, Messenger/analysis
- Secretory Leukocyte Peptidase Inhibitor
- Serine Proteinase Inhibitors/biosynthesis
- Serine Proteinase Inhibitors/genetics
- Spleen/enzymology
- Spleen/pathology
- Streptococcus pneumoniae
- Swine
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1077
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Lee KK. An unusual case of renal abscess caused by Streptococcus pneumoniae. Clin Infect Dis 1997; 25:919-20. [PMID: 9356810 DOI: 10.1086/597636] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
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1078
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Samson LM, Allen UD, Creery WD, Diaz-Mitoma F, Singh RN. Elevated interleukin-1 receptor antagonist levels in pediatric sepsis syndrome. J Pediatr 1997; 131:587-91. [PMID: 9386664 DOI: 10.1016/s0022-3476(97)70067-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
OBJECTIVE To measure plasma levels of interleukin-1 beta, interleukin-1 receptor antagonist (IL-Ira), and tumor necrosis factor alpha in children with sepsis syndrome. STUDY DESIGN A prospective, observational study of 14 patients aged 5 months to 13 years with sepsis syndrome admitted to a pediatric intensive care unit. Cytokine levels were measured by enzyme-linked immunosorbent assay at baseline and at a 12, 24, and 48 hours and compared with the levels of 21 age-matched control subjects. RESULTS The mean pediatric risk of mortality score was 16.1. Bacterial and viral sepsis was confirmed in five and three patients, respectively. Compared with the levels in the control subjects (mean level of IL-Ira: 654 pg/ml), the IL-Ira levels were elevated in the septic patients, with mean values of 17855 (p < 0.001), 12771 (p < 0.001), 9182 (p < 0.01), and 2296 pg/ml (p = not significant) at baseline and at 12, 24, and 48 hours, respectively. The IL-Ira level was greater than 1000-fold higher than the IL-1 beta level at all time points in 13 of 14 septic patients. CONCLUSIONS At the time of hospital admission, circulating IL-Ira levels in a cohort of children with sepsis syndrome were at concentrations known to block IL-1 receptors. Thus additional benefit from exogenous IL-Ira therapy would be questionable. Further studies are indicated to determine whether there is a population of patients with sepsis who could benefit from administration of exogenous IL-Ira.
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1079
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Doit C, Barre J, Cohen R, Bonacorsi S, Bourrillon A, Bingen EH. Bactericidal activity against intermediately cephalosporin-resistant Streptococcus pneumoniae in cerebrospinal fluid of children with bacterial meningitis treated with high doses of cefotaxime and vancomycin. Antimicrob Agents Chemother 1997; 41:2050-2. [PMID: 9303415 PMCID: PMC164066 DOI: 10.1128/aac.41.9.2050] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Cerebrospinal fluid (CSF) was taken from 19 children with bacterial meningitis treated with cefotaxime (300 mg/kg of body weight/day) and vancomycin (60 mg/kg/day). Median levels of drugs in CSF were smaller than expected, as follows: 4.4 microg/ml for cefotaxime, 3.2 microg/ml for desacetylcefotaxime, and 1.7 microg/ml for vancomycin. The median CSF bactericidal titer against an intermediately cefotaxime-resistant pneumococcus was 1:4. Our data suggest at least an additive interaction between the drugs used in this study.
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1080
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Cayé-Thomasen P, Hermansson A, Tos M, Prellner K. Increased secretory capacity of the middle ear mucosa after acute otitis media caused by Haemophilus influenzae type B. Otolaryngol Head Neck Surg 1997; 117:263-7. [PMID: 9334775 DOI: 10.1016/s0194-5998(97)70184-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Secretory otitis media is associated with a highly increased goblet cell density of the middle ear mucosa. Previous studies have shown that a single episode of experimental acute otitis media caused by Streptococcus pneumoniae or nontypeable Haemophilus influenzae is followed by increased goblet cell density for a period of at least 6 months. This condition may create a predisposition for subsequent development of secretory otitis media. We inoculated the middle ears of 25 rats with type B H. influenzae to determine the effect of the bacteria on mucosal secretory capacity. Five rats were euthanized 4, 8, 16, 60, and 180 days after inoculation, followed by dissection, staining, and whole-mount embedding of the middle ear mucosa. The goblet cell density was determined in 24 well-defined localities. Compared with that of 25 normal middle ears, the goblet cell density was significantly increased in almost all counting localities on all days of euthanasia. Thus increased goblet cell density and enlargement of mucosal areas containing goblet cells persisted for 6 months after the acute incident. Inoculation of type B H. influenzae induced an increase of goblet cell density that was higher than the increase after inoculation of S. pneumoniae or nontypeable H. influenzae. We conclude that experimental acute otitis media caused by type B H. influenzae is followed by a longstanding increase of mucosal secretory capacity, which is likely to induce a subsequent development of secretory otitis media.
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1081
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Abstract
The management of rhinosinusitis depends on a number of variables related to the duration and severity of symptoms in the individual patient. Furthermore acute rhinosinusitis is managed differently than chronic rhinosinusitis. Because a variety of conservative and pharmacologic interventions are available, the physician can find it difficult to develop a cohesive and logical approach to treatment. An understanding of the pathophysiology, microbiology, and natural history of rhinosinusitis is necessary to formulate the best treatment plan for the individual patient.
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1082
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Bruunsgaard H, Hartkopp A, Mohr T, Konradsen H, Heron I, Mordhorst CH, Pedersen BK. In vivo cell-mediated immunity and vaccination response following prolonged, intense exercise. Med Sci Sports Exerc 1997; 29:1176-81. [PMID: 9309628 DOI: 10.1097/00005768-199709000-00009] [Citation(s) in RCA: 82] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Epidemiological and experimental studies have shown increased frequency and severity of infections after intense, long-term exercise. This study examines whether an in vivo impairment of the cell-mediated immunity and antibody production can be demonstrated after intense, long-term exercise. Twenty-two male triathletes performed one-half an ironman (group A). Vaccinations with tetanus and diphtheritis toxoid and purified pneumococcal polysaccharide were given after the exercise. Furthermore, a skin test with seven different antigens was applied on the forearm. Antibody titers were measured before and 2 wk after the exercise. The skin test was read 48 h after the application. Eleven non-exercising triathletes (group B) and 22 moderately trained men (group C) were used as control groups. Group A revealed a significantly lower skin test response to the tetanus antigen than both groups B and C. In group A, a smaller cumulative response (sum of the diameters of indurations and number of positive skin test spots) was found than in both groups B and C. No differences in antibody titers were found among the three groups. Thus, the in vivo cell-mediated immunity was impaired in the first days after prolonged, high intensity exercise, whereas there was no impairment of the in vivo antibody production measured 2 wk after vaccination.
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1083
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Abstract
The management of rhinosinusitis depends on a number of variables related to the duration and severity of symptoms in the individual patient. Furthermore acute rhinosinusitis is managed differently than chronic rhinosinusitis. Because a variety of conservative and pharmacologic interventions are available, the physician can find it difficult to develop a cohesive and logical approach to treatment. An understanding of the pathophysiology, microbiology, and natural history of rhinosinusitis is necessary to formulate the best treatment plan for the individual patient.
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1084
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New pneumococcal-vaccine recommendations include strategies for increasing vaccine use. Am J Health Syst Pharm 1997; 54:1688. [PMID: 9262738 DOI: 10.1093/ajhp/54.15.1688a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
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1085
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Fletcher TJ, Tunnicliffe WS, Hammond K, Roberts K, Ayres JG. Simultaneous immunisation with influenza vaccine and pneumococcal polysaccharide vaccine in patients with chronic respiratory disease. BMJ (CLINICAL RESEARCH ED.) 1997; 314:1663-5. [PMID: 9193290 PMCID: PMC2126836 DOI: 10.1136/bmj.314.7095.1663] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
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1086
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al-Rajhi AA, Wagoner MD. Penetrating keratoplasty in congenital hereditary endothelial dystrophy. Ophthalmology 1997; 104:956-61. [PMID: 9186436 DOI: 10.1016/s0161-6420(97)30200-0] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
PURPOSE The purpose of the study is to determine the outcome of penetrating keratoplasty in congenital hereditary endothelial dystrophy. METHODS Records of 40 patients (13 males, 27 females) who underwent penetrating keratoplasty (56 eyes) were reviewed. The mean age at surgery was 11.8 years (range, 2 months-35 years). The mean follow-up was 37 months (range, 6-136 months). RESULTS In 35 (62.5%) of 56 eyes that underwent primary penetrating keratoplasty, the grafts survived. Graft survival analysis showed the probability of obtaining a clear graft is 92% at 1 year, 72% at 2 years, and 56.5% at 5 years. Graft survival was statistically better in eyes where onset of the disease is delayed (P = 0.02), if the graft donor age is between 5 and 30 years versus older than 30 years (P = 0.02), and for patients who kept follow-up appointments versus those who were delinquent (P < 0.03). Visual acuity was 20/40 in 1.9%, 20/50 to 20/80 in 18.9%, 20/100 to 20/300 in 49%, and less than 20/400 in 30.2%. The main causes of graft failure were graft rejection (six eyes) and bacterial keratitis (four eyes). CONCLUSIONS Penetrating keratoplasty in congenital hereditary endothelial dystrophy is moderately successful, and graft survival is better in cases of delayed onset compared with that of congenital onset. Early surgical intervention is recommended to prevent development or progression of amblyopia.
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1087
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Bergus G. Serious bacterial infection in children. THE JOURNAL OF FAMILY PRACTICE 1997; 44:531-532. [PMID: 9191620] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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1088
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Zeleny R, Altmann F, Praznik W. A capillary electrophoretic study on the specificity of beta-galactosidases from Aspergillus oryzae, Escherichia coli, Streptococcus pneumoniae, and Canavalia ensiformis (jack bean). Anal Biochem 1997; 246:96-101. [PMID: 9056188 DOI: 10.1006/abio.1996.9973] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The specificities of the beta-galactosidases from Aspergillus oryzae, Escherichia coli, Streptococcus pneumoniae, and Canavalia ensiformis (jack bean) have been studied by capillary zone electrophoresis. Various di- and oligosaccharides as well as a biantennary asialo N-glycan were used as substrates. Following enzymatic hydrolysis, the mixtures of substrates and products were derivatized with ethyl 4-aminobenzoate and separated by high-performance capillary electrophoresis in a borate buffer system using uv detection. Baseline separation of the respective peaks was obtained in 4 min, allowing the analysis of a large number of samples. Therefore, initial rates of hydrolysis could be determined. The beta-galactosidase from A. oryzae exhibited minimal activity toward Galbeta1-3GlcNAc. In contrast to the enzyme from S. pneumoniae which is almost specific for beta1-4 linkages, the Aspergillus galactosidase readily hydrolyzed Galbeta1-4GlcNAc and Galbeta1-6GlcNAc. Neither of the four beta-galactosidases acted upon Galbeta1-4(Fucalpha1-3)GlcNAcbeta1-3Galbeta1-4Gl c (lacto-N-fucopentaose III) even though the corresponding nonfucosylated oligosaccharides were good substrates. With the exception of the enzyme from E. coli, the beta-galactosidases degalactosylated a biantennary N-linked oligosaccharide.
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1089
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Doyle NA, Bhagwan SD, Meek BB, Kutkoski GJ, Steeber DA, Tedder TF, Doerschuk CM. Neutrophil margination, sequestration, and emigration in the lungs of L-selectin-deficient mice. J Clin Invest 1997; 99:526-33. [PMID: 9022088 PMCID: PMC507828 DOI: 10.1172/jci119189] [Citation(s) in RCA: 119] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
These studies tested the hypothesis that L-selectin plays a role in neutrophil traffic in the lungs, particularly in neutrophil margination, sequestration, and emigration, using L-selectin-deficient mice. No defect in neutrophil margination within either capillaries or arterioles and venules was observed in uninflamed lungs of L-selectin-deficient mice. The initial rapid sequestration of neutrophils within the pulmonary capillaries 1 min after intravascular injection of complement fragments was not prevented. In contrast, L-selectin did contribute to the prolonged neutrophil sequestration (> or = 5 min). Interestingly, neutrophil accumulation within noncapillary microvessels required L-selectin at both 1 and 5 min after complement injection. During bacterial pneumonias, L-selectin played a role in neutrophil accumulation within noncapillary microvessels in response to either Escherichia coli or Streptococcus pneumoniae and within capillaries in response to E. coli but not S. pneumoniae. However, L-selectin was not required for emigration of neutrophils or edema in response to either organism. These studies demonstrate a role for L-selectin in the prolonged sequestration of neutrophils in response to intravascular complement fragments, in the intracapillary accumulation of neutrophils during E. coli-induced pneumonia, and in the accumulation of neutrophils within noncapillary microvessels when induced by either intravascular complement fragments or
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1090
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Bradley JS, Scheld WM. The challenge of penicillin-resistant Streptococcus pneumoniae meningitis: current antibiotic therapy in the 1990s. Clin Infect Dis 1997; 24 Suppl 2:S213-21. [PMID: 9126696 DOI: 10.1093/clinids/24.supplement_2.s213] [Citation(s) in RCA: 76] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Bacterial meningitis caused by Streptococcus pneumoniae is an important cause of neurological morbidity and mortality in both children and adults. With increasing antibiotic resistance in pneumococci and documented microbiological failure in treatment of pneumococcal meningitis with cefotaxime and ceftriaxone, the need for alternative antibiotic therapy is critical. Of the currently available options, vancomycin has shown the most promise, particularly when used in combination with ceftriaxone or cefotaxime. Rifampin, also used in combination with either ceftriaxone or cefotaxime, has demonstrated encouraging preliminary results against antibiotic-resistant pneumococci as well. Chloramphenicol has unexpectedly yielded discouraging clinical results in children with infection caused by penicillin-resistant strains. Of the investigational antibiotics currently in clinical trials for the treatment of meningitis, meropenem, a carbapenem-class antibiotic, has demonstrated increased activity against penicillin-resistant pneumococci compared with that of other beta-lactam antibiotics, while having a safety profile similar to that of the cephalosporins.
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1091
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1092
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Dobroszycki J, Abadi J, Lambert G, Beenhouwer DO, Truong TH, Wiznia AA. Testicular abscess due to Streptococcus pneumoniae in an infant with human immunodeficiency virus infection. Clin Infect Dis 1997; 24:84-5. [PMID: 8994772 DOI: 10.1093/clinids/24.1.84] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
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1093
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FIRSHEIN W. INFLUENCE OF DEOXYRIBONUCLEIC ACID DEGRADATION PRODUCTS AND ORTHOPHOSPHATE ON DEOXYNUCLEOTIDE KINASE ACTIVITY AND DEOXYRIBONUCLEIC ACID SYNTHESIS IN PNEUMOCOCCUS TYPE 3. J Bacteriol 1996; 90:327-36. [PMID: 14329443 PMCID: PMC315646 DOI: 10.1128/jb.90.2.327-336.1965] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Firshein, William (Wesleyan University, Middletown, Conn.). Influence of deoxyribonucleic acid degradation products and orthophosphate on deoxynucleotide kinase activity and deoxyribonucleic acid synthesis in pneumococcus type III. J. Bacteriol. 90:327-336. 1965.-An oligodeoxynucleotide fraction derived from a deoxyribonuclease-treated calf-thymus deoxyribonucleic acid (DNA) can enhance the activity of deoxycytidylic acid (dCMP) and deoxyguanylic acid (dGMP) kinases in cell suspensions of type III pneumococci. High levels of orthophosphate can produce similar effects. For part of the incubation period, the activity of dCMP and dGMP kinases is very low or undetectable in unsupplemented-cell suspensions of pneumococci. In contrast, the remaining kinases, deoxyadenylic acid and thymidylic acid, which are present in ample amounts in control and supplemented cells throughout the incubation period, are unaffected by the addition of oligodeoxynucleotides and orthophosphate. The stimulation of kinase activity is amino acid-dependent and can be abolished by adding chloramphenicol. When the oligodeoxynucleotide fraction and orthophosphate are further supplemented with all eight of the naturally occurring deoxynucleosides and deoxynucleotides (which do not affect kinase activity), a preferential enhancement of DNA synthesis occurs in comparison with cell growth or protein synthesis. Addition of deoxynucleosides and deoxynucleotides to unsupplemented cells produces only a slight increase in DNA synthesis. The preferential enhancement of DNA synthesis can be prevented by adding chloramphenicol at a certain time during incubation.
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1094
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1095
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1096
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SMALL T, BRAUN W, FIRSHEIN W. INFLUENCE OF POLYANIONS ON GROWTH AND DEOXYRIBONUCLEIC ACID SYNTHESIS OF DIPLOCOCCUS PNEUMONIAE. J Bacteriol 1996; 87:972-3. [PMID: 14137646 PMCID: PMC277126 DOI: 10.1128/jb.87.4.972-973.1964] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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1097
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1098
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RAVIN AW, DESA JH. GENETIC LINKAGE OF MUTATIONAL SITES AFFECTING SIMILAR CHARACTERS IN PNEUMOCOCCUS AND STREPTOCOCCUS. J Bacteriol 1996; 87:86-96. [PMID: 14102878 PMCID: PMC276966 DOI: 10.1128/jb.87.1.86-96.1964] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Ravin, Arnold W. (University of Rochester, Rochester, N.Y.), and Joscelyn D. H. De Sa. Genetic linkage of mutational sites affecting similar characters in pneumococcus and streptococcus. J. Bacteriol. 87:86-96. 1964.-By interspecific transformation, deoxyribonucleic acid (DNA) determinants conferring resistance to high levels of streptomycin in pneumococcus were found to be allelic with DNA determinants conferring low levels of streptomycin resistance in the Challis and NBSI strains of streptococcus. The reciprocal transformation (low resistance pneumococcus x high resistance streptococcus) led to the same conclusion. In addition, determinants controlling resistance to erythromycin in pneumococcus and the Challis strain of streptococcus were found to become closely linked after interspecific transformation. Modifier genes influencing the phenotype conferred by mutations at the streptomycin-resistance locus differentiate species to a certain extent. The results demonstrate that transformations between pneumococcus and streptococcus are not due to episomes, but involve recombinational events in which genetic material of the host species is replaced by homologous material that performed a similar function in the donor species.
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1099
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DISTLER J, ROSEMAN S. POLYSACCHARIDE AND GLYCOLIPID SYNTHESIS BY CELL-FREE PREPARATIONS FROM TYPE XIV PNEUMOCOCCUS. Proc Natl Acad Sci U S A 1996; 51:897-905. [PMID: 14173009 PMCID: PMC300180 DOI: 10.1073/pnas.51.5.897] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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1100
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Abstract
The growth of Escherichia coli is reversibly inhibited by drugs of the morphine series. The order of inhibitory effectiveness for the drugs tested was levallorphan > levorphanol > dextrorphan > nalorphine > morphine. The synthetic analgesic, levorphanol, was studied in greater detail. Its effectiveness was found to be strongly dependent on the pH of the medium. Raising the pH of the medium provides a higher concentration of the neutral free base which is thought to diffuse across cell membranes more readily. However, considerations other than the rate of entry of drug into the cells must be of importance since an already established growth inhibition is promptly reversed upon lowering the pH of the medium. Two mutants of Escherichia coli with altered sensitivity to levorphanol were isolated.
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