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1.
Br J Surg ; 99(6): 807-12, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22473359

ABSTRACT

BACKGROUND: Axillary ultrasonography (AUS) and fine-needle aspiration cytology (FNAC) can establish axillary lymph node status before surgery, although this technique is hampered by poor adequacy rates. To achieve consistently high rates of FNAC adequacy, rapid on-site evaluation (ROSE) of FNAC samples was introduced. METHODS: This single-centre, retrospective observational study of patients with newly diagnosed breast cancer undergoing preoperative AUS and FNAC between February 2008 and November 2010 examined the effect of the introduction of ROSE. RESULTS: A total of 381 patients were included. AUS revealed 152 axillae with suspicious radiological features. FNAC was positive for malignant cells in 75 (49·3 per cent) of 152 samples. Sentinel lymph node mapping was avoided in 75 patients, representing 19·7 per cent of the entire study population. Adequacy rates increased from 78 per cent to 96 per cent following the introduction of ROSE (P = 0·001). The overall sensitivity and specificity of AUS and FNAC was 80·6 and 100 per cent respectively. A lymph node diameter equal to or larger than 10 mm and extranodal extension were significantly associated with positive FNAC (P < 0·001 and P = 0·012 respectively). Maximum lymph node diameter of at least 10 mm was an independent predictor of positive FNAC (odds ratio 11·2, 95 per cent confidence interval 3·32 to 37·76; P < 0·001). CONCLUSION: AUS with FNAC provided accurate preoperative staging of the axilla for metastatic breast disease and avoided unnecessary sentinel lymph node mapping. The introduction of ROSE ensured the efficiency of AUS and FNAC.


Subject(s)
Adenocarcinoma, Mucinous/pathology , Biopsy, Fine-Needle/methods , Breast Neoplasms/pathology , Carcinoma, Ductal, Breast/pathology , Carcinoma, Lobular/pathology , Lymph Nodes/pathology , Adult , Aged , Axilla , Feasibility Studies , Female , Humans , Lymphatic Metastasis , Middle Aged , Neoplasm Staging/methods , Point-of-Care Systems , Prenatal Care/methods , Sensitivity and Specificity , Sentinel Lymph Node Biopsy/methods , Ultrasonography, Interventional
2.
Ir J Med Sci ; 176(2): 87-90, 2007.
Article in English | MEDLINE | ID: mdl-17486294

ABSTRACT

BACKGROUND: To assess changing trends in histological types of thyroid cancer in an Irish hospital over the past 30 years. METHODS: Biographical data, tumour characteristics, treatment and outcome from 190 patients with thyroid carcinoma from 1970 to 2000 were reviewed retrospectively. RESULTS: Detailed records of 190 patients with thyroid cancer were identified with a mean age at presentation of 50 years. From 1970 to 1979 the distribution of histological types was: papillary carcinoma; 9 patients (4.7%), follicular; 17 patients (8.9%), anaplastic; 9 patients (4.7%), medullary; 1 patient (0.5%) and lymphoma; 1 patient (0.5%). From 1980 to 1989 papillary carcinoma accounted for 32 patients (16.8%), follicular; 14 patients (7.3%), anaplastic; 13 patients (6.8%), medullary; 7 patients (3.7%) and lymphoma; 5 patients (2.6%). From 1990 to 1999 papillary cancer accounted for 48 patients (25.2%), follicular; 14 patients (7.3%), anaplastic; 8 patients (4.2%), medullary; 7 patients (3.7%) and lymphoma; 5 patients (2.6%). Survival rates were significantly better for those aged less than 45 years (P < 0.0001), female sex (P < 0.01) and those with papillary carcinoma (P < 0.01). CONCLUSIONS: This study demonstrated a significant increase in the incidence of papillary carcinoma. This may be related to increasing dietary iodine intake and may be significant as papillary carcinoma is associated with a more favourable prognosis.


Subject(s)
Thyroid Neoplasms/epidemiology , Thyroid Neoplasms/pathology , Age Factors , Carcinoma, Papillary/epidemiology , Diet , Female , Humans , Incidence , Iodine/administration & dosage , Ireland/epidemiology , Male , Middle Aged , Prognosis , Retrospective Studies , Thyroid Neoplasms/mortality
3.
Curr Med Chem ; 14(2): 233-41, 2007.
Article in English | MEDLINE | ID: mdl-17266582

ABSTRACT

In this review we discuss the features of a new class of antiretroviral combinations, namely "Virostatics". Virostatics are characterized by the combination of a drug directly inhibiting virus production (viro), and another drug indirectly inhibiting the virus by reducing cellular proliferation (static). In particular, we will focus on the combination of hydroxyurea and didanosine against HIV-1. Hydroxyurea and didanosine synergize to control viral replication and present with a favorable resistance profile, suppressing several resistant quasi-species. Because virostatics target essential cellular proteins, they exert an immune modulating activity and reduce viral targets (CD4 T cells), possibly with limited immunosuppressive effects. Importantly, a dose-finding clinical study has shown that decreasing the dose of hydroxyurea not only diminishes toxicity but also increases antiviral potency. Therefore, the combination of hydroxyurea and didanosine strikes a balance between viral suppression, drug-related toxicity and viral escape, and could have a role both in induction and maintenance therapy. In this review we would like to appraise what is known about hydroxyurea and didanosine and specifically address the major advantages, i.e. novel mechanism of action leading to a new class of drugs and resistance profile providing durability, as well as the major criticisms of this combination, i.e. toxicity and reasons for prescribing a perceived immune suppressant to immune compromised patients.


Subject(s)
Anti-HIV Agents/pharmacology , Cell Proliferation/drug effects , Didanosine/pharmacology , Drug Therapy, Combination , Humans , Hydroxyurea/pharmacology , Immunosuppression Therapy , Virus Replication/drug effects
4.
Curr Pharm Des ; 10(32): 4103-20, 2004.
Article in English | MEDLINE | ID: mdl-15579091

ABSTRACT

The combination of three or more antiretroviral drugs is referred to as highly active antiretroviral therapy (HAART) and constitutes the standard of care for HIV-1 patients in industrialized nations. Although HAART is usually effective in reducing viral load and re-constituting CD4 counts, latent virus reservoirs persist, and as many as 60 years therapy [1, 2] may be required to eradicate the virus. Meanwhile, patients are likely to experience drug related toxicity and may have to change therapy due to the emergence of drug resistant strains. For these reasons, the search for different therapeutic approaches continues. A new concept of antiviral/cytostatic ("virostatics") drugs has been proposed within the context of HAART to restrict virus target populations (CD4(+) T lymphocytes), target viral reservoirs, and possibly restore immune functions, by reducing excess immune activation, a fundamental component of HIV/AIDS pathogenesis. These virostatics include drugs such as hydroxyurea, mycophenolic acid, leflunomide and rapamycin, which are currently used for other therapeutic indications; and other experimental drugs, which are not for human use. They utilize multiple novel mechanisms of action to impede HIV by targeting host cellular proteins that are not susceptible to mutation. Therefore, their resistance profile appears to be quite favorable. Since many of these drugs act by inhibiting the synthesis of deoxynucleotides, essential for HIV reverse transcription, they favor the incorporation of nucleoside analogues into viral DNA, thus synergizing with the antiviral activity of currently used nucleoside reverse transcriptase inhibitors (NRTI). The rationale for the use of virostatics in HIV/AIDS, their mechanism of action, and ongoing preclinical and clinical research will be reviewed.


Subject(s)
Anti-HIV Agents , HIV Infections/drug therapy , HIV-1/drug effects , Animals , Anti-HIV Agents/pharmacology , Anti-HIV Agents/therapeutic use , Antiretroviral Therapy, Highly Active , CD4 Lymphocyte Count , CD4-Positive T-Lymphocytes/drug effects , CD4-Positive T-Lymphocytes/immunology , DNA, Viral/biosynthesis , HIV Infections/immunology , HIV Infections/virology , HIV-1/metabolism , Humans , Viral Load
5.
Eur J Surg Oncol ; 29(9): 707-10, 2003 Nov.
Article in English | MEDLINE | ID: mdl-14602487

ABSTRACT

AIMS: Cyclo-oxygenase (Cox) catalyses the conversion of arachidonic acid into prostaglandins (PG) and other eciosanoids. The prostaglandins, especially PGE(2) are implicated in tumorigenesis via angiogenesis and suppression of immune reactivity. There are two known isoforms of the enzyme, Cox-1, which is constitutively expressed and the inducible isoform, Cox-2. Cox-2 is induced in response to inflammatory mediators, growth factors, oncogenes and mitogens. Non-selective Cox inhibitors may reduce the relative risk of colonic and breast carcinoma. METHODS: We studied the expression of Cox-2 by immunohistochemistry in 106 primary breast carcinoma specimens collected over a three-year period, using a commercially available polyclonal antibody on formalin-fixed, paraffin-embedded tissue. The slides were examined independently by two pathologists. Tumours were classified according to accepted criteria and an immunohistochemical score (IHS) was calculated for each specimen. The IHS combines the percentage of immunoreactive cells (quantity score) and an estimate of staining intensity (staining intensity score). RESULTS: All patients were female. The mean age was 53 years, range 28-86 years. Forty percent (n=42) of tumours were node negative and 60% (n=64) node positive. Forty-nine percent (n=52) of tumours were grade 3, a further 49% (n=52) grade 2 and 2% (n=2) grade 1. There was no statistically significant correlation between IHS and tumour size, grade, histology, nodal status, estrogen receptor or progesterone receptor positivity. A trend was observed showing an IHS of zero is associated with prolonged survival compared with an IHS of 9-12. CONCLUSION: Cox-2 expression in primary breast cancer does not correlate with accepted pathological or biochemical prognostic indicators.


Subject(s)
Biomarkers, Tumor/metabolism , Breast Neoplasms/metabolism , Breast Neoplasms/mortality , Isoenzymes/metabolism , Prostaglandin-Endoperoxide Synthases/metabolism , Adult , Aged , Aged, 80 and over , Breast Neoplasms/enzymology , Breast Neoplasms/pathology , Carcinoma, Ductal, Breast/metabolism , Carcinoma, Ductal, Breast/mortality , Carcinoma, Intraductal, Noninfiltrating/metabolism , Carcinoma, Intraductal, Noninfiltrating/mortality , Carcinoma, Lobular/metabolism , Carcinoma, Lobular/mortality , Cyclooxygenase 2 , Female , Follow-Up Studies , Humans , Immunohistochemistry , Membrane Proteins , Middle Aged , Neoplasm Staging , Predictive Value of Tests , Prognosis , Survival Analysis
6.
Clin Microbiol Infect ; 9(7): 653-61, 2003 Jul.
Article in English | MEDLINE | ID: mdl-12925106

ABSTRACT

OBJECTIVE: To test the activity of telithromycin against 1034 Streptococcus pneumoniae isolates from pediatric patients in ten centers from ten central and eastern European countries during 2000-2001, and to compare it with the activities of erythromycin A, azithromycin, clarithromycin, clindamycin, and quinupristin-dalfopristin. METHODS: The minimum inhibitory concentrations (MICs) of telithromycin, erythromycin A, azithromycin, clarithromycin, clindamycin, levofloxacin, quinupristin-dalfopristin and penicillin G were tested by the agar dilution method with incubation in air, and mechanisms of resistance to macrolides and quinolones were investigated. RESULTS: Strains were isolated from sputum, tracheal aspirates, ear, eye, blood, and cerebrospinal fluid. Among S. pneumoniae strains tested, 36% had raised penicillin G MICs (>/= 0.12 mg/L). Susceptibilities were as follows: telithromycin, quinupristin-dalfopristin and levofloxacin, >/= 99%; clindamycin, 83%; and erythromycin A, azithromycin and clarithromycin, 78%. Of 230 (22.3%) erythromycin A-resistant S. pneumoniae strains, 176 (79.6%) had erm(B), 38 (16.1%) had mef(A), and 10 (4.3%) had mutations in 23S ribosomal RNA or in ribosomal protein L4. The rates of drug-resistant S. pneumoniae are high in all centers except Kaunas, Riga, and Prague. CONCLUSION: Telithromycin had low MICs against all strains, irrespective of macrolide, azalide or clindamycin resistance. Ribosomal methylation was the most prevalent resistance mechanism among all resistant strains, except in Sofia, where the prevalence of the efflux mechanism was higher.


Subject(s)
Anti-Bacterial Agents/pharmacology , Ketolides , Macrolides , Streptococcus pneumoniae/drug effects , Adolescent , Child , Child, Preschool , Drug Resistance, Bacterial/physiology , Electrophoresis, Gel, Pulsed-Field , Humans , Infant , Infant, Newborn
7.
Clin Microbiol Infect ; 9(7): 741-5, 2003 Jul.
Article in English | MEDLINE | ID: mdl-12925122

ABSTRACT

In total, 1039 pediatric Streptococcus pyogenes isolates from Bulgaria, Croatia, the Czech Republic, Hungary, Latvia, Lithuania, Poland, Romania, Slovakia and Slovenia were studied. All strains were susceptible to penicillin G, levofloxacin, and quinupristin-dalfopristin, 91-100% to telithromycin, and 82-100% to erythromycin, azithromycin, and clarithromycin, and 90-100% to clindamycin. Macrolide resistance occurred mainly in Slovakia (25%), the Czech Republic (17.3%), and Croatia (15.8%). Overall, 9.7% of S. pyogenes isolates were erythromycin resistant due to erm(B)- or erm(A)-encoded methylases (72.3%) or to a mef(A)-encoded efflux pump (25.7%). One strain had alterations of both 23S rRNA (A2058G Escherichia coli numbering) and ribosomal protein L22 (G95D).


Subject(s)
Anti-Bacterial Agents/pharmacology , Ketolides , Macrolides , Streptococcal Infections/drug therapy , Streptococcus pyogenes/drug effects , Adolescent , Child , Child, Preschool , Drug Resistance, Bacterial , Europe/epidemiology , Humans , Infant , Infant, Newborn , Methylation , Ribosomes/metabolism , Streptococcal Infections/epidemiology , Streptococcus pyogenes/isolation & purification
8.
Curr Drug Targets Infect Disord ; 3(2): 171-8, 2003 Jun.
Article in English | MEDLINE | ID: mdl-12769793

ABSTRACT

The induction of a Th-1 polarized immune response is believed to be advantageous when designing immunologic approaches for HIV therapy. DNA vaccines represent one of the best immunologic strategies capable of inducing such a response. From conception to clinical application it is now possible to rationally design DNA vaccines based on reliable experimental data, thus a systemic approach to the development of new and the enhancement of existing vaccine immunogens is now possible. The addition of adjuvants may also increase immunogenicity and depending on the choice of adjuvant, polarize the immune response. Other important factors in the formulation of a successful vaccine are the selection of administration route, heterologous or homologous prime/boost schedules, and the feasibility of the eventual clinical application. This review will summarize recently developed preventive and therapeutic vaccines, and carefully evaluate the advantages and potential risks for Human Immunodeficiency Virus (HIV) infected patients. Finally, the concept of "autovaccination" will be defined as it represents the basis for the development of our innovative therapeutic antigen presenting cell targeted HIV vaccine. DermaVir is the first topical vaccine, in combination with antiretroviral therapy, to demonstrate immunological and clinical benefits in a relevant animal model (chronically infected rhesus macaques).


Subject(s)
AIDS Vaccines/immunology , HIV Infections/immunology , HIV Infections/therapy , HIV/immunology , AIDS Vaccines/administration & dosage , AIDS Vaccines/standards , Animals , Clinical Trials, Phase I as Topic , HIV Infections/prevention & control , HIV Infections/virology , Humans , Macaca mulatta , Mice , Vaccines, DNA/administration & dosage , Vaccines, DNA/immunology , Vaccines, DNA/standards
9.
J R Coll Surg Edinb ; 47(4): 599-607, 2002 Aug.
Article in English | MEDLINE | ID: mdl-12365423

ABSTRACT

In patients with primary hyperparathyroidism, neck exploration by an experienced parathyroid surgeon is curative in excess of 95% of cases. Considerable efforts have been devoted to improving parathyroid imaging. New radionucleotide agents and scanning procedures have markedly improved the success rate of localization studies with subsequent development of minimally invasive surgical techniques. In this article we review the different localization techniques and their current role in parathyroid surgery for primary hyperparathyroidism


Subject(s)
Hyperparathyroidism/diagnosis , Hyperparathyroidism/surgery , Practice Patterns, Physicians' , Humans
10.
Ir J Med Sci ; 171(1): 28-30, 2002.
Article in English | MEDLINE | ID: mdl-11993590

ABSTRACT

BACKGROUND: With the increasing incidence of breast cancer in patients over 70 years, there is interest in the best therapeutic approach. AIMS: To review the management of breast cancer in elderly women and to identify the factors involved in the decision to treat patients with tamoxifen as first line therapy. PATIENTS AND METHODS: Between 1986 and 1999, 302 female patients aged > or = 70 years presented with primary breast cancer, of whom 219 underwent surgery, 79 received tamoxifen as first line treatment and four received primary radiotherapy. A retrospective review was performed on these 79 patients and the outcome recorded. RESULTS: Of these 79 patients, data was available on 68. Follow-up ranged from one to 63 months (median 17 months). Co-morbidity was the principal reason for choosing first line tamoxifen therapy in 61% and patient preference in 11%. Tumour size was less than 5cm in 51%. In 25% tumour size decreased, in 24% it remained stable and in 27% it increased in size following tamoxifen therapy. Additional treatment was prescribed for 33% of patients. CONCLUSION: In the authors' experience, for those elderly patients suffering considerable co-morbidity or who refuse surgical intervention, tamoxifen is an acceptable alternative.


Subject(s)
Antineoplastic Agents, Hormonal/therapeutic use , Breast Neoplasms/drug therapy , Tamoxifen/therapeutic use , Aged , Breast Neoplasms/surgery , Combined Modality Therapy , Comorbidity , Female , Follow-Up Studies , Humans , Receptors, Estrogen/analysis , Retrospective Studies , Time Factors , Treatment Outcome
11.
Clin Microbiol Infect ; 8(12): 814-22, 2002 Dec.
Article in English | MEDLINE | ID: mdl-12519357

ABSTRACT

Agar dilution MIC was used to test the activity of RWJ 54428, a new cephalosporin derivative, compared to imipenem, meropenem, ceftriaxone, piperacillin, piperacillin-tazobactam, clindamycin and metronidazole against 363 anaerobes isolated from clinical specimens. RWJ 54428 had low MICs against most beta-lactamase-negative Gram-negative rods, and all Gram-positive strains except Clostridium difficile. Imipenem and meropenem had the lowest MICs (MIC50s of 0.125 mg/L and MIC90s of 1.0 mg/L). Piperacillin-tazobactam, clindamycin and metronidazole were active against most strains, and ceftriaxone was active mainly against beta-lactamase-negative organisms.


Subject(s)
Bacteria, Anaerobic/drug effects , Cephalosporins/pharmacology , Bacteria, Anaerobic/growth & development , Microbial Sensitivity Tests
12.
Antimicrob Agents Chemother ; 45(2): 589-92, 2001 Feb.
Article in English | MEDLINE | ID: mdl-11158759

ABSTRACT

Agar dilution MIC methodology was used to compare the activity of BMS 284756 with those of ciprofloxacin, levofloxacin, moxifloxacin, trovafloxacin, amoxicillin-clavulanate, piperacillin-tazobactam, imipenem, clindamycin, and metronidazole against 357 anaerobes. Overall, the respective MICs at which 50% of the isolates tested were inhibited (MIC(50)s) and MIC(90)s (in micrograms per milliliter) were as follows: BMS 284756, 0.5 and 2.0; ciprofloxacin, 2.0 and 16.0; levofloxacin, 1.0 and 8.0; moxifloxacin, 0.5 and 4.0; trovafloxacin, 0.5 and 2.0; amoxicillin-clavulanate, 0.5 and 2.0; piperacillin-tazobactam, 0.25 and 8.0; imipenem, 0.06 and 1.0; clindamycin, 0.25 and 8.0; and metronidazole, 1.0 and >16.0. BMS 284756 is a promising new quinolone with excellent antianaerobic activity.


Subject(s)
Anti-Infective Agents/pharmacology , Bacteria, Anaerobic/drug effects , Fluoroquinolones , Indoles , Quinolones , Bacteria, Anaerobic/enzymology , Clavulanic Acid/pharmacology , Drug Resistance, Microbial , Enzyme Inhibitors/pharmacology , Microbial Sensitivity Tests , beta-Lactamase Inhibitors
13.
Issues Ment Health Nurs ; 22(4): 337-52, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11885153

ABSTRACT

In this existential-phenomenological investigation seven women were interviewed about their experiences of recovering from rape trauma. The purpose of the study was to discover the meaning of recovery from the perception of the victim, how recovery is experienced, and what contributed to the growth and recovery of the woman who has been raped. Transcribed interviews were analyzed using a hermeneutic process. The thematic structure of a woman's recovery from rape comprises three main themes: reaching out, reframing the rape, and redefining the self. These findings are important to professionals working with women who have been raped because it is the raped woman, rather than the clinician, who is able to define what constitutes recovery.


Subject(s)
Adaptation, Psychological , Rape/psychology , Adult , Existentialism , Female , Humans , Interview, Psychological , Middle Aged , Psychiatric Nursing , Self Concept
15.
Blood ; 96(2): 719-26, 2000 Jul 15.
Article in English | MEDLINE | ID: mdl-10887140

ABSTRACT

Pluripotent hematopoietic stem cells have been studied extensively, but the events that occur during their differentiation remain largely uncharted. To develop a system that allows the differentiation of cultured multipotent progenitors by time-lapse fluorescence microscopy, myelomonocytic cells were labeled with green fluorescent protein (GFP) in vivo. This was achieved by knocking the enhanced GFP (EGFP) gene into the murine lysozyme M (lys) locus and using a targeting vector, which contains a neomycin resistant (neo) gene flanked by LoxP sites and "splinked" ends, to increase the frequency of homologous recombination. Analysis of the blood and bone marrow of the lys-EGFP mice revealed that most myelomonocytic cells, especially mature neutrophil granulocytes, were fluorescence-positive, while cells from other lineages were not. Removal of the neo gene through breeding of the mice with the Cre-deleter strain led to an increased fluorescence intensity. Mice with an inactivation of both copies of the lys gene developed normally and were fertile. (Blood. 2000;96:719-726)


Subject(s)
Fluorescence , Gene Transfer Techniques , Granulocytes/cytology , Luminescent Proteins/genetics , Macrophages/cytology , Muramidase/genetics , Animals , Cell Separation , Flow Cytometry , Gene Expression , Gene Targeting , Genetic Vectors , Genotype , Granulocytes/metabolism , Green Fluorescent Proteins , Hematopoietic Stem Cells/cytology , Luminescent Proteins/analysis , Macrophages/metabolism , Mice , Mice, Transgenic
16.
EMBO J ; 19(9): 1987-97, 2000 May 02.
Article in English | MEDLINE | ID: mdl-10790365

ABSTRACT

The bZip transcription factor MafB is expressed specifically in the myeloid lineage of the hematopoietic system and is up-regulated successively during myeloid differentiation from multipotent progenitors to macrophages. Here we report that this induction reflects an essential role of MafB in early myeloid and monocytic differentiation. We observed that the expression of MafB in transformed chicken hematopoietic precursors dramatically increases the proportion of myeloid colony formation at the expense of multipotent progenitor-type colonies. In addition, the overexpression of MafB in transformed myeloblasts stimulates the rapid formation of macrophages, as judged by morphology, surface marker expression and functional criteria. MafB-induced macrophages exhibit typical levels of phagocytic activity and nitric oxide release after activation by lipopolysaccharide. By contrast, overexpression of the myeloid transcription factor PU.1 in these cells does not induce macrophage differentiation. Furthermore, a dominant-negative allele of MafB inhibits both myeloid colony formation and the differentiation of myeloblasts into macrophages. Taken together, our results indicate that MafB induction is a specific and essential determinant of the monocytic program in hematopoietic cells.


Subject(s)
Avian Proteins , Cell Differentiation , DNA-Binding Proteins , Macrophages/cytology , Monocytes/cytology , Oncogene Proteins/metabolism , Trans-Activators/metabolism , Transcription Factors , Amino Acid Sequence , Animals , Biomarkers/analysis , Cell Line, Transformed , Cell Size , Chick Embryo , Colony-Forming Units Assay , Genes, Dominant/genetics , Hematopoietic Stem Cells/cytology , Hematopoietic Stem Cells/metabolism , Lipopolysaccharides/pharmacology , Macrophage Activation/drug effects , Macrophages/drug effects , Macrophages/metabolism , MafB Transcription Factor , Monocytes/metabolism , Mutation/genetics , Nitric Oxide/metabolism , Oncogene Proteins/genetics , Oncogene Proteins v-myb/genetics , Oncogene Proteins v-myb/physiology , Phagocytosis , Protein Binding , Proto-Oncogene Proteins/genetics , Proto-Oncogene Proteins/metabolism , Quail , Temperature , Trans-Activators/genetics , Transcriptional Activation , Transfection
17.
J Clin Microbiol ; 38(4): 1444-8, 2000 Apr.
Article in English | MEDLINE | ID: mdl-10747123

ABSTRACT

Agar dilution and microdilution (both in air) and E test and disk diffusion (both in air and CO(2)) were used to test the activity of telithromycin against 110 erythromycin-susceptible and 106 erythromycin-resistant pneumococci. The MICs at which 50 and 90% of strains are inhibited (MIC(50)s and MIC(90)s, respectively) for erythromycin-susceptible strains varied between 0.008 and 0.016 microg/ml and 0.016 and 0.03 microg/ml when the samples were incubated in air. By comparison, telithromycin MIC(50)s and MIC(90)s for erythromycin-resistant strains were in air 0.03 to 0.125 and 0. 125 to 0.5 microg/ml, respectively. When agar dilution was used as the reference method, essential agreement was found for 112 of 216 strains (51.9%) for microdilution, 168 of 216 (77.8%) for E test in air, and 132 of 216 (61.1%) for E test in CO(2). With the exception of four strains tested by E test in CO(2), all organisms were susceptible to a proposed telithromycin susceptibility breakpoint of < or =1 microg/ml. By disk diffusion with 15-microg telithromycin disks, all strains but one had zones of inhibition > or =19 mm in diameter when incubated in CO(2), while all strains had zone diameters of > or = 22 mm when incubated in air. Zone diameters in air were generally 4 to 5 mm larger than in CO(2). By all methods, MICs and zones of all erythromycin-resistant strains occurred in clusters separated from those seen with erythromycin-susceptible strains. The results for macrolide-resistant strains with erm and mef resistance determinants were similar. The results show that (i) telithromycin is very active against erythromycin-susceptible and -resistant strains irrespective of macrolide resistance mechanism; (ii) susceptibility to telithromycin can be reliably tested by the agar, microdilution, E test, and disk diffusion methods; and (iii) incubation in CO(2) led to smaller zones by disk diffusion and higher MICs by E test, but at a susceptible MIC breakpoint of < or =1 microg/ml and a susceptible zone diameter cutoff of > or =19 mm in CO(2), 215 of 216 strains were found to be susceptible to telithromycin.


Subject(s)
Anti-Bacterial Agents/pharmacology , Ketolides , Macrolides , Microbial Sensitivity Tests/methods , Pneumococcal Infections/microbiology , Streptococcus pneumoniae/drug effects , Colony Count, Microbial , Drug Resistance, Microbial , Erythromycin/pharmacology , Humans , Streptococcus pneumoniae/growth & development
19.
Antimicrob Agents Chemother ; 44(2): 304-10, 2000 Feb.
Article in English | MEDLINE | ID: mdl-10639354

ABSTRACT

The activities of gemifloxacin compared to those of nine other agents was tested against a range of penicillin-susceptible and -resistant pneumococci by agar dilution, microdilution, time-kill, and post-antibiotic effect (PAE) methods. Against 64 penicillin-susceptible, 68 penicillin-intermediate, and 75 penicillin-resistant pneumococci (all quinolone susceptible), agar dilution MIC(50)s (MICs at which 50% of isolates are inhibited)/MIC(90)s (in micrograms per milliliter) were as follows: gemifloxacin, 0.03/0.06; ciprofloxacin, 1.0/4.0; levofloxacin, 1.0/2. 0; sparfloxacin, 0.5/1.0; grepafloxacin, 0.125/0.5; trovafloxacin, 0. 125/0.25; amoxicillin, 0.016/0.06 (penicillin-susceptible isolates), 0.125/1.0 (penicillin-intermediate isolates), and 2.0/4.0 (penicillin-resistant isolates); cefuroxime, 0.03/0.25 (penicillin-susceptible isolates), 0.5/2.0 (penicillin-intermediate isolates), and 8.0/16.0 (penicillin-resistant isolates); azithromycin, 0.125/0.5 (penicillin-susceptible isolates), 0. 125/>128.0 (penicillin-intermediate isolates), and 4.0/>128.0 (penicillin-resistant isolates); and clarithromycin, 0.03/0.06 (penicillin-susceptible isolates), 0.03/32.0 (penicillin-intermediate isolates), and 2.0/>128.0 (penicillin-resistant isolates). Against 28 strains with ciprofloxacin MICs of >/=8 microg/ml, gemifloxacin had the lowest MICs (0.03 to 1.0 microg/ml; MIC(90), 0.5 microg/ml), compared with MICs ranging between 0.25 and >32.0 microg/ml (MIC(90)s of 4.0 to >32.0 microg/ml) for other quinolones. Resistance in these 28 strains was associated with mutations in parC, gyrA, parE, and/or gyrB or efflux, with some strains having multiple resistance mechanisms. For 12 penicillin-susceptible and -resistant pneumococcal strains (2 quinolone resistant), time-kill results showed that levofloxacin at the MIC, gemifloxacin and sparfloxacin at two times the MIC, and ciprofloxacin, grepafloxacin, and trovafloxacin at four times the MIC were bactericidal for all strains after 24 h. Gemifloxacin was uniformly bactericidal after 24 h at

Subject(s)
Anti-Bacterial Agents/pharmacology , Anti-Infective Agents/pharmacology , Fluoroquinolones , Naphthyridines/pharmacology , Streptococcus pneumoniae/drug effects , Gemifloxacin , Humans , Microbial Sensitivity Tests
20.
J Clin Microbiol ; 37(10): 3296-9, 1999 Oct.
Article in English | MEDLINE | ID: mdl-10488195

ABSTRACT

This study evaluated the susceptibility of pneumococci to cefditoren by agar dilution and microdilution methods (both in air) and by E-test (AB Biodisk, Solna, Sweden) and disk diffusion methods (both in CO(2)). By the three MIC tests, the MICs at which 50 and 90% of isolates were inhibited (MIC(50)s and MIC(90)s) were, respectively, as follows (in micrograms per milliliter): for the 65 penicillin-susceptible strains tested, 0.016 and 0.03 (by agar dilution), 0.016 and 0.03 (by microdilution), and 0.016 and 0.03 (by E test); for the 68 penicillin-intermediate strains tested, 0.125 and 0.5 (by agar dilution), 0.125 and 0.5 (by microdilution), and 0. 25 and 0.5 (by E test); and for the 67 penicillin-resistant strains tested, 1.0 and 1.0 (by agar dilution), 0.5 and 1.0 (by microdilution), and 1.0 and 1.0 (by E test). With tentative cefditoren breakpoints (in micrograms per milliliter) of /=8.0 (resistant), all strains were susceptible to cefditoren by agar, microdilution, and E-test results; with breakpoints of /=4.0 microg/ml, 97% of strains were cefditoren susceptible by agar dilution results, 98% were susceptible by microdilution results, and 99% were susceptible by E-test results. When microdilution and E-test results were compared to those from the reference agar dilution method, 191 (95.5%) and 183 (91.5%) of strains gave essential agreement (+/-1 log(2) dilution); 8 (2.7%) minor discrepancies were found for both methods with a breakpoint of /=20 (susceptible), 17 to 19 (intermediate), and /=16 mm (susceptible). All three methods for testing the MIC of cefditoren showed excellent correlation.


Subject(s)
Cephalosporins/pharmacology , Microbial Sensitivity Tests/methods , Streptococcus pneumoniae/drug effects , Diffusion
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