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1.
Front Mol Biosci ; 10: 1180689, 2023.
Article in English | MEDLINE | ID: mdl-37122560

ABSTRACT

Aneuploidy in preimplantation embryos is a major cause of human reproductive failure. Unlike uniformly aneuploid embryos, embryos diagnosed as diploid-aneuploid mosaics after preimplantation genetic testing for aneuploidy (PGT-A) can develop into healthy infants. However, the reason why these embryos achieve full reproductive competence needs further research. Current RNA sequencing techniques allow for the investigation of the human preimplantation transcriptome, providing new insights into the molecular mechanisms of embryo development. In this prospective study, using euploid embryo gene expression as a control, we compared the transcriptome profiles of inner cell mass and trophectoderm samples from blastocysts with different levels of chromosomal mosaicism. A total of 25 samples were analyzed from 14 blastocysts with previous PGT-A diagnosis, including five low-level mosaic embryos and four high-level mosaic embryos. Global gene expression profiles visualized in cluster heatmaps were correlated with the original PGT-A diagnosis. In addition, gene expression distance based on the number of differentially expressed genes increased with the mosaic level, compared to euploid controls. Pathways involving apoptosis, mitosis, protein degradation, metabolism, and mitochondrial energy production were among the most deregulated within mosaic embryos. Retrospective analysis of the duration of blastomere cell cycles in mosaic embryos revealed several mitotic delays compared to euploid controls, providing additional evidence of the mosaic status. Overall, these findings suggest that embryos with mosaic results are not simply a misdiagnosis by-product, but may also have a genuine molecular identity that is compatible with their reproductive potential.

2.
Br J Hosp Med (Lond) ; 81(11): 1-14, 2020 Nov 02.
Article in English | MEDLINE | ID: mdl-33263466

ABSTRACT

The hand is an extremely versatile organ adapted for fine tasks with various clinicoanatomical compartments. This article reviews the types of common hand infections that present to the emergency department and/or hand surgeon, with relevant investigations and strategies for diagnosis and treatment, with the emphasis on distinguishing between superficial and more serious infections.


Subject(s)
Hand , Infections , Hand/pathology , Humans , Infections/diagnosis , Infections/therapy
4.
Hum Reprod ; 28(3): 794-800, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23293223

ABSTRACT

STUDY QUESTION: Does female obesity affect the dynamic parameters of embryo quality assessed by time-lapse analysis? SUMMARY ANSWER: Female obesity does not affect the dynamic embryo quality as determined by image acquisition and time-lapse analysis. WHAT IS KNOWN ALREADY: Female obesity impairs natural and assisted reproduction but there is no agreement on the specific contribution of gametes, embryos or endometrial receptivity. In this preliminary study the dynamic parameters of embryo quality are assessed for the first time by time-lapse analysis. STUDY DESIGN, SIZE, DURATION: Two-year cohort retrospective study comparing embryos from three groups of patients according to the presence of infertility and/or obesity. PARTICIPANTS AND SETTING: Participants attended a University-affiliated private clinic where ICSI was performed. Using an IVF incubator with a built-in camera designed to automatically acquire images at defined time points, we monitored individual embryos from 89 patients: 71 embryos from 13 obese infertile women, 242 embryos from 45 normoweight infertile women and 111 embryos from 31 normoweight fertile oocyte donors. The chronological pattern of cell divisions (timings of cell cleavages) and other morphologic features (time-dependent cell size and nucleation) was recorded. MAIN RESULTS AND THE ROLE OF CHANCE: Embryos from obese and normoweight infertile women showed similar cleavage patterns, but occurring more slowly, to those from fertile donors. These differences were statistically significant for t2 (time of cleavage to two-blastomere embryo) (P = 0.016), t3 (P = 0.014), t4 (P = 0.003) and t5 (P = 0.040). LIMITATIONS, REASONS FOR CAUTION: These are preliminary data from a retrospective analysis with a limited sample size. GENERALIZABILITY TO OTHER POPULATIONS: Not recommended until further studies using time-lapse analysis of a larger sample have been performed. STUDY FUNDING/COMPETING INTEREST(S): None.


Subject(s)
Blastocyst/pathology , Ectogenesis , Infertility, Female/complications , Infertility, Female/pathology , Obesity/complications , Adult , Body Mass Index , Cell Division , Cell Size , Cohort Studies , Embryo Culture Techniques , Female , Humans , Image Processing, Computer-Assisted , Infertility, Female/therapy , Kinetics , Oocyte Donation , Retrospective Studies , Time-Lapse Imaging
5.
J Contam Hydrol ; 128(1-4): 47-57, 2012 Feb 01.
Article in English | MEDLINE | ID: mdl-22192344

ABSTRACT

Argillaceous formations are thought to be suitable natural barriers to the release of radionuclides from a radioactive waste repository. However, the safety assessment of a waste repository hosted by an argillaceous rock requires knowledge of several properties of the host rock such as the hydraulic conductivity, diffusion properties and the pore water composition. This paper presents an experimental design that allows the determination of these three types of parameters on the same cylindrical rock sample. The reliability of this method was evaluated using a core sample from a well-investigated indurated argillaceous formation, the Opalinus Clay from the Mont Terri Underground Research Laboratory (URL) (Switzerland). In this test, deuterium- and oxygen-18-depleted water, bromide and caesium were injected as tracer pulses in a reservoir drilled in the centre of a cylindrical core sample. The evolution of these tracers was monitored by means of samplers included in a circulation circuit for a period of 204 days. Then, a hydraulic test (pulse-test type) was performed. Finally, the core sample was dismantled and analysed to determine tracer profiles. Diffusion parameters determined for the four tracers are consistent with those previously obtained from laboratory through-diffusion and in-situ diffusion experiments. The reconstructed initial pore-water composition (chloride and water stable-isotope concentrations) was also consistent with those previously reported. In addition, the hydraulic test led to an estimate of hydraulic conductivity in good agreement with that obtained from in-situ tests.


Subject(s)
Aluminum Silicates/chemistry , Models, Chemical , Water/chemistry , Clay , Diffusion , Finite Element Analysis , Mass Spectrometry , Porosity , Switzerland
6.
Public Health ; 123(6): 444-7, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19464715

ABSTRACT

OBJECTIVES: To describe the epidemiology of an outbreak of Salmonella enteritidis phage type 1 (PT1) infection associated with a fast food premises, and to identify the causative factors leading to an acute outbreak with high attack rate and severe illness including hospital admission. STUDY DESIGN: Integrated descriptive study of epidemiology, food and environmental microbiology, and professional environmental health assessment, supplemented by a case-case analytical study. METHODS: Cases were identified through multiple sources and were interviewed to identify food items consumed. Descriptive epidemiology of all cases and a case-case analytical study of risk factors for severe illness were undertaken. Microbiological investigation included analysis and typing of pathogens from stools, blood and environmental surfaces. Professional environmental heath assessment of the premises was undertaken. RESULTS: S. enteritidis PT1 was recovered from two-thirds of faecal samples. Three cases had dual infection with enterotoxin-producing Clostridium perfringens. S. enteritidis PT1 was isolated from 14 of 40 food samples examined and C. perfringens was isolated from eight food samples. Environmental health inspection of the premises revealed multiple deficiencies, including deficits in food preparation and hygiene consistent with multiple cross-contamination, and time-temperature abuse of sauces widely used across menu items. Severe cases were associated with consumption of chips and salad. CONCLUSIONS: Outbreaks from fast food premises have been infrequently described. This outbreak demonstrates the potential for fast food premises, with multiple deficiencies in food preparation and hygiene, to produce large, intense community outbreaks with high attack rates and severe illness, highly confined in space and time.


Subject(s)
Restaurants , Salmonella Food Poisoning/epidemiology , Salmonella enteritidis/isolation & purification , Adult , Cooking , Female , Food Contamination , Humans , Hygiene , London/epidemiology , Male
8.
Mol Hum Reprod ; 7(11): 1007-13, 2001 Nov.
Article in English | MEDLINE | ID: mdl-11675466

ABSTRACT

The aim of this study was to understand the androgen-related factors which may regulate concentrations of the tumour marker, prostate-specific antigen (PSA). We therefore measured the serum concentrations of total and free testosterone and of sex hormone-binding globulin (SHBG) and determined the androgen receptor (AR) gene CAG repeat length, then compared these values to total and free PSA concentrations in 91 subjects with proven fertility, and 112 subfertile men with defective spermatogenesis. Concentrations of free testosterone and total testosterone, adjusted for SHBG, were 17-20% lower in subfertile men compared with those in their fertile counterparts. This subtle, but highly significant (P < 0.001), difference in testosterone between fertile and subfertile men was accentuated by the positive correlation between testosterone and AR gene CAG repeat length in fertile, but not subfertile, subjects. In subfertile subjects, testosterone strongly correlated (r = 0.354, P < 0.001) with PSA concentrations, and independent of testosterone, total PSA negatively correlated (r = -0.229, P = 0.011) with AR CAG length. Overall our data suggest that, firstly, PSA correlates with testosterone only in an environment of relatively low androgenicity, such as in subfertile men. Secondly, in such a low androgenic environment, short CAG tracts (associated with high AR activity) correlate positively with PSA concentrations. These results suggest that interpretation of PSA is best made in conjunction with testosterone concentrations and AR CAG length.


Subject(s)
Infertility, Male/genetics , Polymorphism, Genetic , Prostate-Specific Antigen/blood , Receptors, Androgen/genetics , Sex Hormone-Binding Globulin/metabolism , Testosterone/blood , Adult , Humans , Infertility, Male/blood , Male , Reference Values , Trinucleotide Repeats/genetics
9.
Ann Trop Paediatr ; 21(2): 147-8, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11471258

ABSTRACT

Rotavirus infection is common in childhood. We report a 2-year-old boy admitted to hospital with gastro-enteritis who suffered cardio-respiratory arrest and died. Autopsy showed evidence of rotavirus-associated myocarditis and pneumonitis. We are not aware of any previous report of death from this type of consequence of rotavirus infection.


Subject(s)
Myocarditis/virology , Pneumonia, Viral/virology , Rotavirus Infections/diagnosis , Fatal Outcome , Gastroenteritis/virology , Humans , Infant , Male , Myocarditis/diagnosis , Pneumonia, Viral/diagnosis
10.
Fertil Steril ; 75(2): 275-81, 2001 Feb.
Article in English | MEDLINE | ID: mdl-11172827

ABSTRACT

OBJECTIVE: To determine whether changes in the polymorphic trinucleotide (CAG) tract of the androgen receptor gene are associated with spermatogenic defects in patients with male infertility. DESIGN: Case-control study of two ethnic groups. SETTING: University referral centers for male infertility at Baylor College of Medicine, Houston, Texas, and National University Hospital, Singapore. PARTICIPANT(S): Two hundred and fifteen patients with male infertility and depressed spermatogenesis and 142 fertile controls. MAIN OUTCOME MEASURE(S): Size of androgen receptor CAG alleles according to fluorescent-labeled polymerase chain reaction and automated analysis using Genescan software (PE Biosystems Asia, Singapore), and statistical examination of its relation to clinical variables. RESULT(S): In U.S. patients, the mean androgen receptor CAG length was significantly longer in infertile patients than in fertile controls (21.95 +/- 0.31 vs. 20.72 +/- 0.52). Logistic regression showed that each unit increase in CAG length was associated with a 20% increase in the odds of being azoospermic. The odds ratio for azoospermia was sevenfold higher for patients with > or =26 CAG repeats than in those with <26 CAG repeats. Although mean CAG length in Singapore patients was longer than in the U.S. samples, long androgen receptor CAG alleles were significantly related to male infertility in both populations. CONCLUSION(S): Long (> or =26) androgen receptor CAG alleles, which are found in up to 25% of azoospermic men, are associated with male infertility and defective spermatogenesis. Conception in these men is possible with assisted reproductive technologies, as many have spermatozoa in their testes.


Subject(s)
Genetic Markers , Infertility, Male/genetics , Polymorphism, Genetic , Receptors, Androgen/genetics , Trinucleotide Repeats , Biopsy , Case-Control Studies , Codon , Ethnicity/genetics , Humans , Logistic Models , Male , Oligospermia/genetics , Polymerase Chain Reaction , Risk Factors , Singapore , Spermatogenesis , Testis/pathology , United States
11.
Cleft Palate Craniofac J ; 37(6): 596-7, 2000 Nov.
Article in English | MEDLINE | ID: mdl-11108530

ABSTRACT

OBJECTIVE: Microform cleft lip (MCL), also known as congenital healed cleft lip, is a rare anomaly that is thought to be a spontaneously healed variant of the more common clefting of lip and palate. Although conventional clefting is known to be associated with congenital heart disease (CHD), MCL has not been similarly associated. We present one patient with MCL and CHD in the form of coarctation of the aorta, an association not previously described. CONCLUSION: As is done in patients with cleft lip, cleft palate, or both, patients with MCL should be carefully examined for evidence of CHD and referred to a pediatric cardiologist if deemed advisable.


Subject(s)
Aortic Coarctation/complications , Cleft Lip/complications , Ductus Arteriosus, Patent/complications , Cleft Lip/classification , Follow-Up Studies , Humans , Infant, Newborn , Male , Subclavian Artery/abnormalities
12.
J Endocrinol Invest ; 23(9): 573-7, 2000 Oct.
Article in English | MEDLINE | ID: mdl-11079451

ABSTRACT

Normal spermatogenesis depends on a sequential cascade of genetic events triggered by factors encoded by sex chromosomes. To determine the contribution of genetic aberrations to male infertility, the X-linked androgen receptor (AR) gene was examined for mutations and polymorphisms in a large cohort of infertile men. Genetic screening of over 400 patients and controls showed that defects in the AR gene lead to the production of dysfunctional receptor protein in up to 10% of males with abnormally low sperm production and male infertility. The dozens of mutations and polymorphisms uncovered were associated with subtly reduced intrinsic AR activity, and are of two main categories: polymorphic changes in length of a trinucleotide CAG tract in the N-terminal transactivation domain, and missense mutations in the C-terminal ligand-binding domain. These polymorphisms and mutations are associated with reduced AR function due to defective intermolecular protein-protein interactions with coactivator molecules. Genetic screening for AR mutations and polymorphism should be offered to severely oligospermic and azoospermic patients. These traits can be transmitted to progeny, and counseling can be offered to affected families. Clarification of the molecular mechanisms of pathogenesis has led to rational hormonal therapy.


Subject(s)
Infertility, Male/genetics , Mutation , Polymorphism, Genetic , Receptors, Androgen/genetics , Humans , Male , Point Mutation , Receptors, Androgen/chemistry , Receptors, Androgen/physiology , Repetitive Sequences, Nucleic Acid , Structure-Activity Relationship
13.
Ann Acad Med Singap ; 29(3): 396-400, 2000 May.
Article in English | MEDLINE | ID: mdl-10976396

ABSTRACT

INTRODUCTION: Although infertility affects about 5% of the male population, its cause in most cases is uncertain. Normal spermatogenesis depends on a sequential cascade of genetic events triggered by factors encoded by the sex chromosomes. To determine the contribution of genetic aberrations to male infertility, the X-linked androgen receptor gene and the Y-chromosome were examined for mutations in a large cohort of infertile men. METHODS: Screening of the androgen receptor (AR) gene for single-stranded conformation polymorphisms, confirmation by DNA sequencing, structure-function studies with androgen-responsive reporter genes and chimeric-protein constructs were performed. Y-chromosome microdeletions screening was done with multiplex polymerase chain reaction (PCR) analyses. RESULTS: Genetic screening of over 400 patients and controls showed that defects in the androgen receptor gene lead to the production of dysfunctional receptor protein in 15% of males with abnormally low sperm production. The dozens of mutations and polymorphisms uncovered were associated with reduced intrinsic androgen receptor activity and involve principally two regions of the androgen receptor. Gene-transfer experiments implicated defective intermolecular protein-protein interactions with coactivator molecules as the cause of reduced receptor function. Submicroscopic deletions of the Y-chromosome were also been detected in about 6% of patients with severely reduced spermatogenesis. The deleted segments encoded RNA-binding proteins of unknown function and are not linked to defects in the androgen receptor. CONCLUSIONS: Mutations and polymorphisms of the AR, and Y-microdeletions cause defective sperm production and male infertility in about 20% of subfertile men. These traits can be transmitted to progeny, and counselling can be offered to affected families. Clarification of the molecular mechanisms of pathogenesis has led to rational hormonal therapy.


Subject(s)
Chromosome Deletion , Infertility, Male/genetics , Receptors, Androgen/genetics , Y Chromosome/genetics , Animals , Humans , Male , Mutation , Polymerase Chain Reaction , Spermatogenesis/genetics , Trinucleotide Repeats/genetics
14.
J Clin Endocrinol Metab ; 85(9): 3484-8, 2000 Sep.
Article in English | MEDLINE | ID: mdl-10999852

ABSTRACT

Hyperandrogenism is currently thought to be central to the pathogenesis of polycystic ovarian syndrome (PCOS), a common endocrine disorder in premenopausal women characterized by irregular menstruation and anovulatory infertility. Although hyperandrogenism is characteristic, some women with PCOS have normal serum androgen levels. All androgens act through the X-linked androgen receptor (AR), the N-terminal domain of which contains a polyglutamine tract encoded by a highly polymorphic CAG trinucleotide repeat tract. Recently, variations in this CAG microsatellite tract, while remaining within the normal polymorphic range (11-38 CAGs), have been inversely correlated with receptor activity. Thus, short tracts are associated with high intrinsic AR activity and increased severity and earlier age of onset of the androgen-regulated tumor prostate cancer, whereas longer CAG tracts are associated with low AR activity and oligospermic infertility. To investigate the role of the CAG repeat tract in PCOS, we measured its length in 91 patients with ultrasound diagnosis of polycystic ovaries, irregular menstrual cycles, and anovulatory infertility and compared them to 112 control subjects of proven fertility with regular menses. Fluorescent-labeled DNA fragments containing the CAG repeat tract were amplified from leucocytic DNA, and their lengths were compared with internal size markers on an automated DNA Sequencer. There were no differences in the mean CAG length between patients and controls when both alleles were considered together or separately. Because there is a subset of PCOS patients whose serum androgens are normal, we compared differences in CAG length between patients whose serum testosterone (T) levels were below the normal laboratory mean, to those that were higher. There was a trend for a lower mean CAG biallelic length among anovulatory patients with T less than 1.73 nmol/L compared with those whose T was more than 1.73 nmol/L (22.47 +/- 0.36 vs. 23.25 +/- 0.29). This difference in CAG length between patients with low and high T levels (20.38 +/- 0.51 vs. 21.98 +/- 0.29) was highly significant (P = 0.004) when only the shorter allele of each individual was considered. Ethnic differences were also evident in our data; Indian subjects had a significantly shorter AR-CAG length compared with Chinese, being 22.08 +/- 0.50 and 23.16 +/- 0.17, respectively. Our data indicate an association between short CAG repeat length and the subset of anovulatory patients with low serum androgens, suggesting that the pathogenic mechanism of polycystic ovaries in these patients could be due to the increased intrinsic androgenic activity associated with short AR alleles.


Subject(s)
Anovulation/genetics , Infertility, Female/genetics , Polycystic Ovary Syndrome/genetics , Receptors, Androgen/biosynthesis , Trinucleotide Repeats/genetics , Adult , Alleles , Anovulation/metabolism , Asian People , Case-Control Studies , DNA/chemistry , DNA/genetics , Female , Gonadal Steroid Hormones/blood , Humans , Infertility, Female/metabolism , Polycystic Ovary Syndrome/metabolism , Receptors, Androgen/genetics , Reverse Transcriptase Polymerase Chain Reaction , Testosterone/blood , White People
15.
Cardiol Young ; 10(1): 57-9, 2000 Jan.
Article in English | MEDLINE | ID: mdl-10695544

ABSTRACT

Tetralogy of Fallot is often found in association with a wide variety of other cardiac lesions, but is rarely found in association with lesions causing obstruction to the left ventricular inflow or outflow. Subaortic stenosis has only rarely been reported in association with tetralogy of Fallot. We report a patient with Marfan syndrome who underwent repair of tetralogy of Fallot at five years of age. Discrete and progressive subaortic stenosis developed two years after the surgical correction, in a previously normal and unobstructed left ventricular outflow tract. Surgical removal of the acquired fibrous subaortic shelf was successful. Clinical signs of obstruction within the left ventricular outflow tract after surgical repair of tetralogy of Fallot should prompt further investigation to exclude the onset of acquired subaortic stenosis.


Subject(s)
Aortic Valve Stenosis/surgery , Marfan Syndrome/complications , Tetralogy of Fallot/surgery , Adolescent , Aortic Valve Stenosis/diagnostic imaging , Aortic Valve Stenosis/etiology , Diagnosis, Differential , Disease Progression , Humans , Male , Tetralogy of Fallot/complications , Ultrasonography
16.
Ann Med ; 32(1): 15-22, 2000 Feb.
Article in English | MEDLINE | ID: mdl-10711573

ABSTRACT

androgens act through a single intracellular androgen receptor (AR) which is encoded by a single-copy gene in the X chromosome. Disruption of the AR by genetic mutation results in complete androgen insensitivity syndrome (CAIS) and the female phenotype in otherwise healthy 46XY individuals. Although CAIS is the best known phenotype, recent studies from our laboratory and elsewhere show that malfunction of the AR is associated with many androgen-regulated diseases or conditions that cross traditional clinical disciplines ranging from paediatrics (ambiguous genitalia), gynaecology (primary amenorrhoea), urology (prostate cancer), neurology (spinal bulbar muscular atrophy), reproductive medicine (male infertility), orthopedics (rheumatoid arthritis), oncology (breast cancer) and dermatology (hirsutism, baldness and acne). Of particular interest are the roles that polymorphic CAG trinucleotide repeat tracts and subtle mutations in the AR ligand-binding domain have in the aetiology of male infertility and prostate cancer, two conditions affecting large numbers of patients. Novel mechanisms of pathogenesis have been uncovered in these cases, and they involve defective protein-protein interactions with coregulator molecules such as TIF2 (transcriptional intermediary factor 2). Knowledge of the critical role that the AR plays in the pathogenesis of these diverse conditions has led to improved diagnostic methods and successful therapy.


Subject(s)
Disorders of Sex Development/genetics , Receptors, Androgen , Androgen-Insensitivity Syndrome/genetics , Humans , Infertility, Male/genetics , Male , Mutation , Prostatic Neoplasms/genetics , Spermatogenesis , Trinucleotide Repeats
17.
Rev Reprod ; 3(3): 141-4, 1998 Sep.
Article in English | MEDLINE | ID: mdl-9829547

ABSTRACT

Male sex steroids (androgens) are important for maintaining sperm production and growth of the accessory sex organ, the prostate gland. This article examines the role of the androgen receptor (AR) in the control of spermatogenesis and focusses on the N-terminal transactivation domain of the receptor, a poorly studied region that is essential for receptor function. This domain is of great interest because of its causative relationship to a fatal neuromuscular disease, spinal bulbar muscular atrophy (Kennedy's syndrome). Genetic screening of the transactivation domain of the AR gene of 153 patients presenting solely with defective spermatogenesis and male infertility, and of over 72 healthy fertile controls was performed. Up to 20% of infertile males have reduced androgenicity caused by an increase in length of a polymorphic trinucleotide (CAG) repeat segment, encoding a polyglutamine tract, of the androgen receptor. The increased risk of male infertility associated with long CAG lengths is associated with reduced risk of prostate cancer. Conversely, short polyglutamine tracts are associated with increased risk of prostate cancer but a reduced risk of male infertility. Thus depressed spermatogenesis and prostate cancer represent opposite ends of the spectrum of androgen receptor transactivation function. Improved understanding of androgen receptor action in these two important public health concerns could lead to rational and effective prevention and therapy.


Subject(s)
Receptors, Androgen/genetics , Receptors, Androgen/physiology , Spermatogenesis/physiology , Transcriptional Activation , Humans , Infertility, Male/genetics , Male , Mutation , Prostatic Neoplasms/genetics , Repetitive Sequences, Nucleic Acid
19.
Yeast ; 13(14): 1319-27, 1997 Nov.
Article in English | MEDLINE | ID: mdl-9392076

ABSTRACT

The deduced translation product of an open reading frame on the left arm of chromosome XVI of Saccharomyces cerevisiae, with the systematic name of YPL061w, is 500 amino acids in length and shares significant homology with aldehyde dehydrogenases. Amino acids 2 to 16 of the protein encoded by YPL061w were found to be identical to the N-terminal 15 amino acids of the purified cytosolic, Mg(2+)-activated acetaldehyde dehydrogenase (ACDH) of S. cerevisiae. This enzyme is thought to be involved in the production of acetate from which cytosolic acetyl-CoA is then synthesized. Deletion of YPL061w was detrimental to the growth of haploid strains of yeast; an analysis of one deletion mutant revealed a maximum specific growth rate (in complex medium containing glucose) of one-third of that displayed by the wild-type strain. Mutants deleted in YPL061w were also unable to use ethanol as a carbon source. As expected, the cytosolic, Mg(2+)-activated ACDH activity had been lost from the mutants, although the mitochondrial, K(+)-activated ACDH was readily detected.


Subject(s)
Aldehyde Oxidoreductases/chemistry , Aldehyde Oxidoreductases/genetics , Cytosol/enzymology , Magnesium/metabolism , Saccharomyces cerevisiae/enzymology , Saccharomyces cerevisiae/genetics , Aldehyde Oxidoreductases/metabolism , Amino Acid Sequence , Base Sequence , Chromosomes, Fungal , Enzyme Activation/genetics , Gene Deletion , Molecular Sequence Data , Multigene Family , Open Reading Frames
20.
J Hosp Infect ; 36(2): 105-16, 1997 Jun.
Article in English | MEDLINE | ID: mdl-9211157

ABSTRACT

A clonal origin for European isolates of antibiotic multi-resistant Pseudomonas aeruginosa serotype O12 has been suggested. This study was designed to assess the value and limitations of several typing methods for the investigation of outbreaks due to this serotype. In Hôpital de Rodez, France, this organism is endemic, and a prospective clinical epidemiological study was undertaken over a 15 month period, encompassing all patients at the hospital from whom P. aeruginosa O12 was isolated. All isolates were examined by auxanogram, antibiogram, phage-typing, electrophoresis of esterases and pulsed-field gel electrophoresis of DNA. The results suggest that (1) the methods used did not clearly differentiate between clinically-related and epidemiologically-unrelated European isolates, (2) in Hôpital de Rodez, while some isolates were likely to have been transmitted from patient-to-patient, most infections or colonizations with this organism were sporadic and their origin is unknown. The limits of typing methods for the investigation of outbreaks of nosocomial infection with multi-resistant P. aeruginosa O12 are emphasized.


Subject(s)
Bacterial Typing Techniques , Cross Infection/epidemiology , Drug Resistance, Multiple , O Antigens/analysis , Pseudomonas Infections/epidemiology , Pseudomonas aeruginosa/classification , Aged , Aged, 80 and over , Bacteriophage Typing/methods , Cross Infection/prevention & control , Disease Outbreaks/prevention & control , Electrophoresis, Gel, Pulsed-Field , Female , France/epidemiology , Genetic Variation , Genotype , Humans , Male , Microbial Sensitivity Tests , Middle Aged , Phenotype , Polymorphism, Restriction Fragment Length , Pseudomonas Infections/prevention & control , Pseudomonas aeruginosa/drug effects
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