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1.
J Hosp Infect ; 99(1): 75-80, 2018 May.
Article in English | MEDLINE | ID: mdl-29128347

ABSTRACT

BACKGROUND: Approximately 19% of morbidity in peripheral vascular surgery is attributable to wound complications, which can result in delayed healing, and also arterial or graft infection leading to limb loss and even mortality in extreme cases. AIM: To determine whether groin wound complications were reduced following the routine introduction of PICO negative pressure wound therapy dressings in patients who underwent peripheral vascular surgery. METHODS: Patients who underwent peripheral vascular surgery from 2011 to 2016 were identified and divided into PICO and non-PICO groups. Patient, procedure and wound characteristics were tabulated and analysed. Patients were followed-up for at least six weeks postoperatively. Wound complication rates, infection confirmed by microbiology, and requirement for re-admission due to wound complications were noted. Basic cost analysis was performed. FINDINGS: In total, 151 patients were analysed (N = 73 PICO, N = 78 non-PICO). No difference in age (P = 0.862), body mass index (P = 0.673), diabetes (P = 0.339), pre-operative albumin (P = 0.196), use of drain (P = 0.343) and history of meticillin-resistant Staphylococcus aureus (P = 0.281) was observed between groups. The PICO group contained more smokers than the non-PICO group (45% vs 29%, P = 0.034). Wound complications were seen in 8% (N = 6) of the PICO group and 19% (N = 15) of the non-PICO group (P = 0.042). No significant difference in infection was found between the two groups (3% vs 6%, P = 0.249), but fewer seromas were observed when PICO dressings were used (1.4% vs 7.7%, P = 0.069). Haematoma (2.7% vs 3.8%, P = 0.531) and dehiscence rates (1.4% vs 1.3%, P = 0.735) were similar between the two groups. CONCLUSIONS: Routine use of PICO dressings is associated with a reduction in wound complication rates following peripheral vascular surgery, and is cost-effective.


Subject(s)
Groin/surgery , Negative-Pressure Wound Therapy , Surgical Wound Infection/prevention & control , Vascular Surgical Procedures/adverse effects , Adult , Aged , Aged, 80 and over , Costs and Cost Analysis , Female , Humans , Male , Middle Aged , Retrospective Studies , Young Adult
2.
JDR Clin Trans Res ; 2(1): 5-9, 2017 Jan.
Article in English | MEDLINE | ID: mdl-30938642

ABSTRACT

ADVOCATE (Added Value for Oral Care) is a project funded by the European Commission's Horizon 2020 program, which aims to develop strategies for a system transition toward more patient-centered and prevention-oriented oral health care delivery within health care systems. This system should balance the restorative and preventive approaches in dental and oral health care. ADVOCATE is a partnership among 6 European Union member states, which involves collaboration among universities, state-funded health care providers, and private insurance companies in Denmark, Germany, Hungary, Ireland, the Netherlands, the United Kingdom, and Aridhia, a biomedical informatics company based in Scotland. There are 6 interrelated work packages, which aim to address the following objectives: 1) in-depth evaluation of oral health care systems in European Union member states to identify best system designs for oral disease prevention, 2) development of a set of measures to provide information on oral care delivery and oral health outcomes, 3) evaluation of a feedback approach in dental practice that aims to facilitate a change toward preventive oral health care delivery, and 4) economic evaluation of strategies to promote preventive oral health care and development of policy recommendations for oral health care systems. The project is novel in its use of data that are routinely collected by health insurance organizations, as well as the engagement of key stakeholders from dental teams, insurers, patients, and policy makers in guiding the development and progress of the project. This article outlines in detail the objectives and research methodology of the ADVOCATE project and its anticipated impact. Knowledge Transfer Statement: This commentary describes the development of policy options to promote a greater focus on disease prevention in general dental practice. The approach builds on identifying the comparative effectiveness of alternative incentive schemes, as well as methods to monitor clinical and patient-derived measures of success in creating health for patients. The article describes the development and application of the measures and the evaluation of their success in orienting clinical practice more toward disease prevention.

3.
J Pharmacol Exp Ther ; 347(1): 7-19, 2013 Oct.
Article in English | MEDLINE | ID: mdl-23860305

ABSTRACT

The most highly abused prescription drugs are opioids used for the treatment of pain. Physician-reported drug-seeking behavior has resulted in a significant health concern among doctors trying to adequately treat pain while limiting the misuse or diversion of pain medications. In addition to abuse liability, opioid use is associated with unwanted side effects that complicate pain management, including opioid-induced emesis and constipation. This has resulted in restricting long-term doses of opioids and inadequate treatment of both acute and chronic debilitating pain, demonstrating a compelling need for novel analgesics. Recent reports indicate that adaptations in endogenous substance P/neurokinin-1 receptor (NK1) are induced by chronic pain and sustained opioid exposure, and these changes may contribute to processes responsible for opioid abuse liability, emesis, and analgesic tolerance. Here, we describe a multifunctional mu-/delta-opioid agonist/NK1 antagonist compound [Tyr-d-Ala-Gly-Phe-Met-Pro-Leu-Trp-NH-Bn(CF3)2 (TY027)] that has a preclinical profile of excellent antinociceptive efficacy, low abuse liability, and no opioid-related emesis or constipation. In rodent models of acute and neuropathic pain, TY027 demonstrates analgesic efficacy following central or systemic administration with a plasma half-life of more than 4 hours and central nervous system penetration. These data demonstrate that an innovative opioid designed to contest the pathology created by chronic pain and sustained opioids results in antinociceptive efficacy in rodent models, with significantly fewer side effects than morphine. Such rationally designed, multitargeted compounds are a promising therapeutic approach in treating patients who suffer from acute and chronic pain.


Subject(s)
Analgesics, Opioid/administration & dosage , Pain Measurement/drug effects , Pain/drug therapy , Receptors, Neurokinin-1/metabolism , Spinal Nerves/drug effects , Spinal Nerves/injuries , Analgesics, Opioid/adverse effects , Analgesics, Opioid/chemistry , Animals , Ferrets , Injections, Intraventricular , Injections, Spinal , Male , Mice , Mice, Inbred ICR , Morphine/administration & dosage , Morphine/adverse effects , Naloxone/administration & dosage , Naloxone/adverse effects , Pain/pathology , Pain Measurement/methods , Rats , Rats, Sprague-Dawley , Receptors, Neurokinin-1/physiology , Spinal Nerves/pathology , Treatment Outcome
4.
Lancet Neurol ; 12(4): 339-45, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23453347

ABSTRACT

BACKGROUND: Lithium has neuroprotective effects in cell and animal models of amyotrophic lateral sclerosis (ALS), and a small pilot study in patients with ALS showed a significant effect of lithium on survival. We aimed to assess whether lithium improves survival in patients with ALS. METHODS: The lithium carbonate in amyotrophic lateral sclerosis (LiCALS) trial is a randomised, double-blind, placebo-controlled trial of oral lithium taken daily for 18 months in patients with ALS. Patients aged at least 18 years who had ALS according to the revised El Escorial criteria, had disease duration between 6 and 36 months, and were taking riluzole were recruited from ten centres in the UK. Patients were randomly assigned (1:1) to receive either lithium or matched placebo tablets. Randomisation was via an online system done at the level of the individual by block randomisation with randomly varying block sizes, stratified by study centre and site of disease onset (limb or bulbar). All patients and assessing study personnel were masked to treatment assignment. The primary endpoint was the rate of survival at 18 months and was analysed by intention to treat. This study is registered with Eudract, number 2008-006891-31. FINDINGS: Between May 26, 2009, and Nov 10, 2011, 243 patients were screened, 214 of whom were randomly assigned to receive lithium (107 patients) or placebo (107 patients). Two patients discontinued treatment and one died before the target therapeutic lithium concentration could be achieved. 63 (59%) of 107 patients in the placebo group and 54 (50%) of 107 patients in the lithium group were alive at 18 months. The survival functions did not differ significantly between groups (Mantel-Cox log-rank χ(2) on 1 df=1·64; p=0·20). After adjusting for study centre and site of onset using logistic regression, the relative odds of survival at 18 months (lithium vs placebo) was 0·71 (95% CI 0·40-1·24). 56 patients in the placebo group and 61 in the lithium group had at least one serious adverse event. INTERPRETATION: We found no evidence of benefit of lithium on survival in patients with ALS, but nor were there safety concerns, which had been identified in previous studies with less conventional designs. This finding emphasises the importance of pursuing adequately powered trials with clear endpoints when testing new treatments. FUNDING: The Motor Neurone Disease Association of Great Britain and Northern Ireland.


Subject(s)
Amyotrophic Lateral Sclerosis/drug therapy , Amyotrophic Lateral Sclerosis/mortality , Aged , Double-Blind Method , Female , Humans , Lithium Carbonate/therapeutic use , Male , Middle Aged , Neuroprotective Agents/therapeutic use , Survival Rate/trends , Treatment Outcome
5.
Ir J Med Sci ; 182(2): 177-83, 2013 Jun.
Article in English | MEDLINE | ID: mdl-22983868

ABSTRACT

BACKGROUND: Fibre-optic bronchoscopy with bronchoalveolar lavage (BAL) is a safe procedure and is associated with low morbidity and mortality in immunocompromised children. Although many studies have highlighted the advantages of positive BAL results in the diagnosis of pulmonary infections, there have been few reports examining the impact of a negative BAL result on clinical management in immunocompromised children on empiric broad-spectrum antimicrobial therapy. AIM: The aim of this study was to evaluate BAL in the diagnosis of pulmonary infections in children with haematological malignancies who develop pneumonia unresponsive to empiric antimicrobial therapy, and also to determine whether a negative BAL result contributed to the clinical management of these patients. MATERIALS AND METHODS: A retrospective review of 44 BAL procedures performed in 33 children with haematological malignancy diagnosed and treated at Our Lady's Children Hospital, Crumlin, Dublin 12, Ireland, over a 10-year period was carried out. RESULTS: We identified a pathogen causing pneumonia in 24 of 44 BAL procedures (54.5 %). The BAL procedure resulted in modification of antimicrobial treatment after 20 of 24 procedures with positive results (83.3 %) in 16 of 20 patients (80 %). Management was changed after 8 of 20 procedures with negative results (40 %) in 8 of 18 patients (44.4 %). The procedure was well tolerated in all patients. CONCLUSIONS: Our study supports the use of bronchoscopy with BAL as a diagnostic intervention in this patient population. We consider BAL a safe procedure from which both positive and negative results contribute to the patient's clinical management.


Subject(s)
Bronchoalveolar Lavage Fluid/microbiology , Hematologic Neoplasms/complications , Pneumonia/diagnosis , Adolescent , Anti-Infective Agents/therapeutic use , Bronchoscopy , Child , Child, Preschool , Female , Hospitals, Pediatric , Humans , Immunocompromised Host , Infant , Ireland , Leukemia/complications , Lymphoma/complications , Male , Pneumonia/drug therapy , Pneumonia/etiology , Retrospective Studies
6.
J Psychiatr Ment Health Nurs ; 17(2): 147-51, 2010 Mar.
Article in English | MEDLINE | ID: mdl-20465760

ABSTRACT

Clinical guidelines have been designed to lead to significant and consistent improvements in health care but are rarely fully implemented within healthcare services. The study involved a survey of staff at four Community Mental Health Teams, which aimed to assess their knowledge and use of both the psychological recommendations of the National Institute for Health and Clinical Excellence (NICE) guidelines for Depression and specifically of cognitive-behavioural therapy (CBT) based interventions. It also aimed to assess team members' clinical assessment skills and decision-making patterns when making recommendations about services for patients with depression. The results indicated that while over 90% of staff said they were using the NICE guidelines for Depression, less than 20% were very confident in using them. Most staff had knowledge about CBT and most (88%) would be very willing to refer to CBT but mentioned problems such as lack of resources and/or social problems affecting service delivery. Most staff were generally able to correctly identify the severity and type of depression. Despite this, some staff were making decisions that were not in accordance with the NICE recommendations. Reasons for these patterns are discussed.


Subject(s)
Community Mental Health Services , Depressive Disorder/nursing , Guideline Adherence , Health Plan Implementation , State Medicine , Attitude of Health Personnel , Clinical Competence , Cognitive Behavioral Therapy , Data Collection , Depressive Disorder/diagnosis , Depressive Disorder/therapy , England , Humans , Inservice Training , Nursing Assessment , Pilot Projects , Primary Health Care , Psychotherapy, Brief , Recurrence
7.
Emerg Med J ; 24(1): 18-21, 2007 Jan.
Article in English | MEDLINE | ID: mdl-17183036

ABSTRACT

OBJECTIVES: To (1) investigate emergency medical care priorities in Kosovo, (2) assess Kosovo's post-war development of emergency medical services and (3) identify expectations. METHODS: An instrument with seven open-ended questions, approved by the institutional review board, was designed for in-person interviews (preferred) or written survey. The survey was administered in October 2003 at the Kosovo University Clinical Center, Pristina, Kosovo, and one regional hospital. Targeted participants were emergency care providers, clinical consultants and health policy consultants. Surveys were conducted by interview with simultaneous interpretation by a native Albanian speaker, an orthopaedic surgeon or in written Albanian form. The responses were evaluated quantitatively and qualitatively. RESULTS: 13 respondents participated in the study: 10 gave interviews and 3 provided written response; 7 were emergency care providers, 4 were emergency care consultants and 2 were health policy consultants. Emergency care priorities were defined as trauma, cardiac disease and suicide. Most respondents believed that emergency medicine as a specialised field was a post-war development. The international community was credited with the provision of infrastructure, supplies and training. Most respondents denied any harm from international assistance. However, some respondents described instances of inappropriate international investment. Ongoing needs are training of providers and equipping of facilities and vehicles. Improved hospital management, political administration and international involvement are thought to be necessary for continued development. CONCLUSIONS: Survey respondents agreed on priorities in emergency care, credited the international community with development to date, and identified administrative structures and international training support as the keys to ongoing development.


Subject(s)
Emergency Medicine/organization & administration , Medical Audit , Warfare , Data Collection , Humans , Interdisciplinary Communication , Needs Assessment , Yugoslavia
8.
J Appl Microbiol ; 96(5): 1013-23, 2004.
Article in English | MEDLINE | ID: mdl-15078518

ABSTRACT

AIM: To develop a real-time PCR detection procedure for Escherichia coli O111, O26 and O157 from minced meat. METHODS AND RESULTS: Strains (n = 8) of each of E. coli O26, E. coli O111 and E. coli O157 were inoculated at ca 10-20 CFU g(-1) into minced retail meat and enriched for 6 h at 41.5 degrees C as follows: E. coli O26 in tryptone soya broth (TSB) supplemented with cefixime (50 microg l(-1)), vancomycin (40 mg l(-1)) and potassium tellurite (2.5 mg l(-1)); E. coli O111 in TSB supplemented with cefixime (50 microg l(-1)) and vancomycin (40 mg l(-1)); E. coli O157 in E. coli broth supplemented with novobiocin (20 mg l(-1)). DNA was extracted from the enriched cultures, and detected and quantified by real-time PCR using verotoxin (vt1 and vt2) and serogroup (O157 per gene; O26 fliC-fliA genes and O111 wzy gene) specific primers. CONCLUSIONS: The methods outlined were found to be sensitive and specific for the routine detection of E. coli O111, O26 and O157 in minced beef. SIGNIFICANCE AND IMPACT OF THE STUDY: The enrichment, isolation and detection procedures used in this study provide a rapid routine-based molecular method for the detection and differentiation of E. coli O26, O111 and O157 from minced meat.


Subject(s)
Escherichia coli/isolation & purification , Food Microbiology , Meat/microbiology , Polymerase Chain Reaction/methods , Culture Media , DNA Probes/genetics , DNA, Bacterial/analysis , Escherichia coli/genetics , Escherichia coli O157/genetics , Escherichia coli O157/isolation & purification , Genes, Bacterial/genetics
9.
J Appl Microbiol ; 95(5): 949-57, 2003.
Article in English | MEDLINE | ID: mdl-14633022

ABSTRACT

AIM: Optimization of enrichment media and selective agars for the detection of Escherichia coli O26 and O111 from minced beef. METHODS AND RESULTS: This study compared a number of different enrichment conditions and plating media for the recovery of E. coli O26 and E. coli O111 from minced beef. The optimum enrichment conditions for E. coli O26 was observed in beef samples enriched at 41.5 degrees C in tryptone soya broth supplemented with cefixime (50 microg l(-1)), vancomycin (40 mg l(-1)) and potassium tellurite (2.5 mg l(-1)). Similar enrichment conditions were optimal for E. coli O111 with the omission of potassium tellurite. The optimum agar for recovery of E. coli O26 and giving the most effective suppression of contaminants was MacConkey agar [lactose replaced by rhamnose (20 g l(-1))] and supplemented with cefixime (50 microg ml(-1)) and potassium tellurite (2.5 mg l(-1)). Optimum recovery of E. coli O111 was on chromocult agar, supplemented with cefixime (50 microg ml(-1)), cefsulodin (5 mg l(-1)) and vancomycin (8 mg l(-1)). Minced beef samples were inoculated with a number of strains of E. coli O26 (n=9) and O111 (n=8), and the developed enrichment and plating methods, used in combination with immunomagnetic separation, were shown to be an effective method for the recovery of all strains. CONCLUSIONS: Routine cultural methods for the recovery of E. coli O26 and O111 from minced beef are described. SIGNIFICANCE AND IMPACT OF THE STUDY: The optimized enrichment and plating procedure described for the recovery of E. coli O111 and O26 from meat can be used to extend research on these emerging pathogens in beef.


Subject(s)
Escherichia coli/isolation & purification , Food Microbiology , Meat/microbiology , Agar , Animals , Bacteriological Techniques/methods , Cattle , Culture Media , Drug Resistance , Escherichia coli/classification , Escherichia coli/growth & development
10.
Acta Crystallogr C ; 57(Pt 12): 1410-4, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11740100

ABSTRACT

The title compounds, 1-ferrocenylmethyl-2-(4-methoxyphenyl)-1H-benzimidazole, [Fe(C5H5)(C20H17N2O)], (I), and 2-(3,4-dimethoxyphenyl)-1-ferrocenylmethyl-1H-benzimidazole, [Fe(C5H5)(C21H19N2O2)], (II), are model electroactive compounds for anion sensor and antimalarial applications. Distortions from the ideal 120 degrees angle about the MeO-C-C groups are evident, with angles of 115.1 (2) and 125.0 (2) degrees in (I), and 115.9 (2) and 124.6 (2) degrees, and 115.7 (2) and 125.1 (2) degrees in (II). The main intermolecular hydrogen bonds in (I) comprise C-H.N and C-H.pi(C5H5) interactions, while in (II), only weak C-H.pi(imidazole) and C-H.pi(arene) interactions are present.

11.
J Appl Microbiol ; 91(1): 131-8, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11442722

ABSTRACT

AIMS: The aim of this study was to perform a detailed characterization of bacteriocins produced by lactic acid bacteria (LAB) isolated from malted barley. METHODS AND RESULTS: Bacteriocin activities produced by eight LAB, isolated from various types of malted barley, were purified to homogeneity by ammonium sulphate precipitation, cation exchange, hydrophobic interaction and reverse-phase liquid chromatography. Molecular mass analysis and N-terminal amino acid sequencing of the purified bacteriocins showed that four non-identical Lactobacillus sakei strains produced sakacin P, while four Leuconostoc mesenteroides strains were shown to produce bacteriocins highly similar or identical to leucocin A, leucocin C or mesenterocin Y105. Two of these bacteriocin-producing strains, Lb. sakei 5 and Leuc. mesenteroides 6, were shown to produce more than one bacteriocin. Lactobacillus sakei 5 produced sakacin P as well as two novel bacteriocins, which were termed sakacin 5X and sakacin 5T. The inhibitory spectrum of each purified bacteriocin was analysed and demonstrated that sakacin 5X was capable of inhibiting the widest range of beer spoilage organisms. CONCLUSION: All bacteriocins purified in this study were class II bacteriocins. Two of the bacteriocins have not been described previously in the literature while the remaining purified bacteriocins have been isolated from environments other than malted barley. SIGNIFICANCE AND IMPACT OF THE STUDY: This study represents a thorough analysis of bacteriocin-producing LAB from malt and demonstrates, for the first time, the variety of previously identified and novel inhibitory peptides produced by isolates from this environment. It also highlights the potential of these LAB cultures to be used as biological controlling agents in the brewing industry.


Subject(s)
Bacteriocins/analysis , Edible Grain/microbiology , Lactobacillus/metabolism , Leuconostoc/metabolism , Amino Acid Sequence , Bacteriocins/chemistry , Bacteriocins/pharmacology , Hordeum , Lactobacillus/drug effects , Lactobacillus/isolation & purification , Leuconostoc/isolation & purification , Microbial Sensitivity Tests , Molecular Sequence Data , Sequence Analysis, Protein , Sequence Homology, Amino Acid
13.
J Clin Microbiol ; 37(9): 2913-9, 1999 Sep.
Article in English | MEDLINE | ID: mdl-10449475

ABSTRACT

The sequence of the rpoB gene from Listeria monocytogenes was determined. Rifampin-resistant (Rif(r)) mutants arising from L. monocytogenes cultures exposed to rifampin were isolated, and by partial sequencing of their rpoB genes, seven different point mutations affecting five different amino acids (473Asp-->Asn or Gly, 479Gly-->Asp, 483His-->Tyr or Leu, 528Ile-->Phe, and 530Ser-->Tyr), which led to MICs of 0.5 to 100 microg/ml for the organisms, were determined. These mutants showed various deficiencies for growth at 42 degrees C, with only one being comparable to the wild-type strain. The interaction of these Rif(r) mutants with human Caco-2 cells was examined by using an immunofluorescence technique. Three mutants failed to interact, while three showed a reduced interaction compared to that of the wild type. It is believed that these pleiotropic phenotypes have arisen as a result of mutations within the DNA-dependent RNA polymerase holoenzyme.


Subject(s)
Antibiotics, Antitubercular/pharmacology , Genes, Bacterial , Listeria monocytogenes/genetics , Plant Proteins/genetics , Rifampin/pharmacology , Base Sequence , Caco-2 Cells/microbiology , DNA-Directed RNA Polymerases , Drug Resistance, Microbial , Humans , Listeria monocytogenes/drug effects , Listeria monocytogenes/growth & development , Microbial Sensitivity Tests , Molecular Sequence Data , Mutation , Temperature
14.
IDrugs ; 2(4): 299-300, 1999 Apr.
Article in English | MEDLINE | ID: mdl-16158347

ABSTRACT

This two-day meeting, attended by approximately 60 delegates, was aimed at researchers in the proteomics field. The proteome is defined as the entire protein content of the cell. Proteomics is the analysis of the end-product of gene expression and all regulations governing gene expression are taken into account, ie, transcriptional and translational. The three stages involved in proteomic analysis are: a separation phase, ie, two dimensional (2D) gel electrophoresis; a characterization phase, ie, mass spectrometry; and, a data analysis phase, ie, bioinformatics.

15.
IDrugs ; 1(2): 191-3, 1998 Jun.
Article in English | MEDLINE | ID: mdl-18465529

ABSTRACT

This two-day meeting provided researchers with an overview of the broad range of targets for possible drug development by highlighting a range of receptor molecules and factors controlling food intake. The direct or indirect role various proteins play in the development of non-insulin dependent diabetes mellitus (NIDDM) or obesity were discussed. Mutations resulting in NIDDM or obesity in animal models were highlighted, although these mapped mutations have not as yet been shown to be the main cause of NIDDM in humans. This further highlights the complexity of these diseases resulting in a broad spectrum phenotype. The importance of NIDDM and obesity research was stressed in the global forecast contributing to social and economic problems in both developed and developing countries. The management and early detection of NIDDM was proposed as the best means of reducing therapeutic costs and the severity of the diseases.

16.
IDrugs ; 1(4): 402-7, 1998 Aug.
Article in English | MEDLINE | ID: mdl-18465570

ABSTRACT

Approximately 2000 academic and industry researchers, and medical doctors attended this symposium on new drugs in cancer. The Netherlands (land of water) its control and its victory in water management was compared to cancer research, and the fight against the disease. The meeting was officially opened by the major of Amsterdam, S Patijn, who highlighted the multicultural characteristics of Amsterdam. Cancer is an international problem and it was very encouraging to see representatives from both developing and developed countries attending the meeting. The conference organizers stressed that the NCI, EORTC, pharmaceutical industries and researchers must strive together to advance cancer research.

17.
Int J Syst Bacteriol ; 46(4): 1004-9, 1996 Oct.
Article in English | MEDLINE | ID: mdl-8863429

ABSTRACT

rRNA sequencing has shown that leuconostocs comprise three distinct phylogenetic lineages which have been designated separate genera (viz., the genera Leuconostoc sensu stricto, Oenococcus, and Weissella). In addition, the 16S rRNA line formed by Oenococcus oeni (formerly Leuconostoc oenos) is exceptionally long; this fact, together with variations in the compositions of conserved positions in the 16S rRNA, has led to the hypothesis (D. Yang and C. R. Woese, Syst. Appl. Microbiol. 12:145-149, 1989) that this organism is a fast-evolving bacterium. Previous evidence that the leuconostocs should be divided into three genera and that O. oeni is an example of tachytelic evolution has come solely from rRNA analyses. In this study we seqenced the rpoC gene encoding the beta' subunit of DNA-dependent RNA polymerase of leuconostocs and performed a comparative phylogenetic analysis. The subdivision of the leuconostocs into three distinct lineages was confirmed by the rpoC gene data, but no evidence that indicated that O. oeni is evolving at an extraordinary rate was found. If O. oeni is truly tachytelic, then fast-evolving phenomena would be expected to occur throughout the whole genome, including this independent molecular chronometer.


Subject(s)
DNA-Directed RNA Polymerases/genetics , Gram-Positive Cocci/classification , RNA, Ribosomal, 16S/analysis , Amino Acid Sequence , Biological Evolution , Gram-Positive Cocci/genetics , Leuconostoc/classification , Leuconostoc/genetics , Molecular Sequence Data , Phylogeny
18.
Int J Cancer ; 55(3): 498-505, 1993 Sep 30.
Article in English | MEDLINE | ID: mdl-8397167

ABSTRACT

The purpose of this study was to determine whether cultured colonic adenoma and carcinoma cells undergo apoptosis (programmed cell death) in vitro and whether specific growth and dietary factors, thought to be involved in the control of growth and differentiation of human colonic cells, could induce cell death through apoptosis. In cell lines originating from 6 colorectal adenomas and 7 carcinomas, spontaneous apoptosis was observed. Sodium butyrate, a naturally occurring fatty acid, is present in the human large bowel in millimolar amounts as a result of bacterial fermentation of dietary fibre. Sodium butyrate, at physiological concentrations, induced apoptosis in 2 adenoma cell lines, RG/C2 and AA/Cl, and in the carcinoma cell line PC/JW/FI. In contrast, transforming growth factor beta 1, which is thought to have an important role in the control of growth in colonic epithelium, did not induce apoptosis. Neither RG/C2 nor PC/JW/FI contain wild-type p53, therefore this tumour-suppressor gene is not required to mediate signals for the induction of apoptosis in colonic tumour cells. Our studies report the induction of apoptosis in colonic tumour cells by the naturally occurring fatty acid sodium butyrate. Since sodium butyrate is produced by bacterial fermentation of dietary fibre, the observation that this fatty acid can induce apoptosis could, in part, explain why a high-fibre diet appears to be protective against colon cancer. Escape from the induction of programmed cell death may be an important event in colorectal carcinogenesis.


Subject(s)
Adenoma/pathology , Apoptosis/drug effects , Butyrates/pharmacology , Carcinoma/pathology , Colonic Neoplasms/pathology , Dietary Fiber/pharmacology , Genes, p53 , Transforming Growth Factor beta/pharmacology , Adenoma/genetics , Apoptosis/genetics , Butyric Acid , Carcinoma/genetics , Colonic Neoplasms/genetics , DNA, Neoplasm/drug effects , Humans , Tumor Cells, Cultured
19.
Int J Cancer ; 51(4): 661-4, 1992 Jun 19.
Article in English | MEDLINE | ID: mdl-1318272

ABSTRACT

In a previous study, using a chemical carcinogen, we converted in vitro a non-tumorigenic cell line derived from a human colorectal diploid adenoma, designated PC/AA, into a tumorigenic cell line which, when inoculated into athymic nude mice, produced progressively growing adenocarcinomas. We now report that continuous in vitro passage of the PC/AA adenoma cell line resulted in its spontaneous transformation to a mucinous carcinoma with a modal karyotype of 51, XY, +i(Iq), +8, +9, +13, +i(13q), -21, +mar. These studies show that a single adenoma can be converted along 2 independent pathways, giving rise to either a mucinous carcinoma or an adenocarcinoma, and provide further experimental evidence for the adenoma-carcinoma sequence. Cytogenetic changes which occur along both pathways to tumorigenicity include abnormalities of chromosome I and multiple copies of chromosome 13. These abnormalities may be important in tumour development and progression in colorectal carcinogenesis.


Subject(s)
Adenocarcinoma, Mucinous/pathology , Adenocarcinoma/pathology , Adenoma/pathology , Colonic Neoplasms/pathology , Colorectal Neoplasms/pathology , Adenocarcinoma/ultrastructure , Adenocarcinoma, Mucinous/ultrastructure , Adenoma/ultrastructure , Animals , Cell Line , Chromosome Aberrations , Colonic Neoplasms/ultrastructure , Colorectal Neoplasms/ultrastructure , Humans , In Vitro Techniques , Karyotyping , Mice , Mice, Nude
20.
Int J Oncol ; 1(2): 201-8, 1992 Jul.
Article in English | MEDLINE | ID: mdl-21584532

ABSTRACT

Two human colorectal adenoma cell lines, S/RG and S/AN, have been continuously passaged in vitro to determine whether they would immortalize and if specific cytogenetic changes were involved in immortalization and tumor progression. At passage 7, S/RG was highly aneuploid, but had no abnormalities of chromosome 1 (Paraskeva et al, Cancer Res 49: 1282-1286, 1989). With continued passage under two independent sets of growth conditions an isochromosome Iq and derivatives of this isochromosome occurred as specific abnormalities. S/AN was near-diploid at passage 10, with a deletion in lp and monosomy 18. The karyotype at passage 44 showed no change. The cell lines are stable in that they have remained anchorage-dependent and non-tumorigenic after several years in culture and S/AN has retained a near diploid karyotype. These cell lines are therefore highly valuable for further studies of tumor progression in human colorectal carcinogenesis.

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