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1.
Int J Food Microbiol ; 205: 7-15, 2015 Jul 16.
Article in English | MEDLINE | ID: mdl-25866906

ABSTRACT

High alcohol concentrations reduce the complexity of wine sensory properties. In addition, health and economic drivers have the wine industry actively seeking technologies that facilitate the production of wines with lower alcohol content. One of the simplest approaches to achieve this aim would be the use of wine yeast strains which are less efficient at transforming grape sugars into ethanol, however commercially available wine yeasts produce very similar ethanol yields. Non-conventional yeast, in particular non-Saccharomyces species, have shown potential for producing wines with lower alcohol content. These yeasts are naturally present in the early stages of fermentation but in general are not capable of completing alcoholic fermentation. We have evaluated 48 non-Saccharomyces isolates to identify strains that, with limited aeration and in sequential inoculation regimes with S. cerevisiae, could be used for the production of wine with lower ethanol concentration. Two of these, Torulaspora delbrueckii AWRI1152 and Zygosaccharomyces bailii AWRI1578, enabled the production of wine with reduced ethanol concentration under limited aerobic conditions. Depending on the aeration regime T. delbrueckii AWRI1152 and Z. bailii AWRI1578 showed a reduction in ethanol concentration of 1.5% (v/v) and 2.0% (v/v) respectively, compared to the S. cerevisiae anaerobic control.


Subject(s)
Ethanol/metabolism , Fermentation , Food Microbiology , Torulaspora/metabolism , Wine , Yeasts/metabolism , Zygosaccharomyces/metabolism , Aerobiosis , Ethanol/analysis , Wine/analysis
2.
Appl Environ Microbiol ; 80(5): 1670-8, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24375129

ABSTRACT

Over recent decades, the average ethanol concentration of wine has increased, largely due to consumer preference for wine styles associated with increased grape maturity; sugar content increases with grape maturity, and this translates into increased alcohol content in wine. However, high ethanol content impacts wine sensory properties, reducing the perceived complexity of flavors and aromas. In addition, for health and economic reasons, the wine sector is actively seeking technologies to facilitate the production of wines with lower ethanol content. Nonconventional yeast species, in particular, non-Saccharomyces yeasts, have shown potential for producing wines with lower alcohol content. These yeast species, which are largely associated with grapes preharvest, are present in the early stages of fermentation but, in general, are not capable of completing alcoholic fermentation. We have evaluated 50 different non-Saccharomyces isolates belonging to 24 different genera for their capacity to produce wine with a lower ethanol concentration when used in sequential inoculation regimes with a Saccharomyces cerevisiae wine strain. A sequential inoculation of Metschnikowia pulcherrima AWRI1149 followed by an S. cerevisiae wine strain was best able to produce wine with an ethanol concentration lower than that achieved with the single-inoculum, wine yeast control. Sequential fermentations utilizing AWRI1149 produced wines with 0.9% (vol/vol) and 1.6% (vol/vol) (corresponding to 7.1 g/liter and 12.6 g/liter, respectively) lower ethanol concentrations in Chardonnay and Shiraz wines, respectively. In Chardonnay wine, the total concentration of esters and higher alcohols was higher for wines generated from sequential inoculations, whereas the total concentration of volatile acids was significantly lower. In sequentially inoculated Shiraz wines, the total concentration of higher alcohols was higher and the total concentration of volatile acids was reduced compared with those in control S. cerevisiae wines, whereas the total concentrations of esters were not significantly different.


Subject(s)
Alcohols/metabolism , Metschnikowia/metabolism , Saccharomyces/metabolism , Wine/microbiology , Biotransformation
3.
Food Chem ; 135(4): 2863-71, 2012 Dec 15.
Article in English | MEDLINE | ID: mdl-22980883

ABSTRACT

Oxygen or lipids are required to complete stressful alcoholic fermentation. Lack of these nutrients can inhibit sugar uptake and growth, which leads to incomplete or 'stuck' fermentation. Oxygen or lipids supplementation not only restores yeast fermentative activity and also affects formation of yeast volatile metabolites. To clarify the effect of oxygen and lipid supplementation on the formation of flavour active metabolites during wine fermentation, we evaluated the addition of these two nutrients to chemically defined grape juice and filter clarified Chardonnay must. Lipid addition increased the concentration of esters, higher alcohols and volatile acids, whereas oxygen increased the concentration of higher alcohols and altered the proportion of acetate to ethyl esters and the proportion of branch-chain acids to medium-chain fatty acids. Combined addition of lipids and oxygen showed an additive effect on concentration of higher alcohols whereas oxygen suppressed the enhancing effect of lipids on formation of esters and volatile acids. Our results demonstrate the potential of lipid and oxygen supplementation for the manipulation of wine aroma in white wine fermentation.


Subject(s)
Lipid Metabolism , Oxygen/metabolism , Saccharomyces cerevisiae/metabolism , Volatile Organic Compounds/chemistry , Wine/analysis , Culture Media/chemistry , Culture Media/metabolism , Fermentation , Lipids/analysis , Oxygen/analysis , Saccharomyces cerevisiae/growth & development , Volatile Organic Compounds/metabolism , Wine/microbiology
4.
Appl Environ Microbiol ; 78(17): 6068-77, 2012 Sep.
Article in English | MEDLINE | ID: mdl-22729542

ABSTRACT

Saccharomyces cerevisiae has evolved a highly efficient strategy for energy generation which maximizes ATP energy production from sugar. This adaptation enables efficient energy generation under anaerobic conditions and limits competition from other microorganisms by producing toxic metabolites, such as ethanol and CO(2). Yeast fermentative and flavor capacity forms the biotechnological basis of a wide range of alcohol-containing beverages. Largely as a result of consumer demand for improved flavor, the alcohol content of some beverages like wine has increased. However, a global trend has recently emerged toward lowering the ethanol content of alcoholic beverages. One option for decreasing ethanol concentration is to use yeast strains able to divert some carbon away from ethanol production. In the case of wine, we have generated and evaluated a large number of gene modifications that were predicted, or known, to impact ethanol formation. Using the same yeast genetic background, 41 modifications were assessed. Enhancing glycerol production by increasing expression of the glyceraldehyde-3-phosphate dehydrogenase gene, GPD1, was the most efficient strategy to lower ethanol concentration. However, additional modifications were needed to avoid negatively affecting wine quality. Two strains carrying several stable, chromosomally integrated modifications showed significantly lower ethanol production in fermenting grape juice. Strain AWRI2531 was able to decrease ethanol concentrations from 15.6% (vol/vol) to 13.2% (vol/vol), whereas AWRI2532 lowered ethanol content from 15.6% (vol/vol) to 12% (vol/vol) in both Chardonnay and Cabernet Sauvignon juices. Both strains, however, produced high concentrations of acetaldehyde and acetoin, which negatively affect wine flavor. Further modifications of these strains allowed reduction of these metabolites.


Subject(s)
Alcohols/metabolism , Metabolic Engineering/methods , Saccharomyces cerevisiae/genetics , Saccharomyces cerevisiae/metabolism , Wine/microbiology , Anaerobiosis , Carbon/metabolism , Carbon Dioxide/metabolism , Energy Metabolism , Fermentation , Glycerol/metabolism
5.
Lett Appl Microbiol ; 55(1): 56-61, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22537453

ABSTRACT

AIMS: The aim of this study was to determine sulphite tolerance for a large number of Dekkera bruxellensis isolates and evaluate the relationship between this phenotype and previously assigned genotype markers. METHODS AND RESULTS: A published microplate-based method for evaluation of yeast growth in the presence of sulphite was benchmarked against culturability following sulphite treatment, for the D. bruxellensis type strain (CBS 74) and a reference wine isolate (AWRI 1499). This method was used to estimate maximal sulphite tolerance for 41 D. bruxellensis isolates, which was found to vary over a fivefold range. Significant differences in sulphite tolerance were observed when isolates were grouped according to previously assigned genotypes and ribotypes. CONCLUSIONS: Variable sulphite tolerance for the wine spoilage yeast D. bruxellensis can be linked to genotype markers. SIGNIFICANCE AND IMPACT OF THE STUDY: Strategies to minimize risk of wine spoilage by D. bruxellensis must take into account at least a threefold range in effective sulphite concentration that is dependent upon the genotype group(s) present. The isolates characterized in this study will be a useful resource for establishing the mechanisms conferring sulphite tolerance for this industrially important yeast species.


Subject(s)
Dekkera/genetics , Genotype , Sulfites/pharmacology , Wine/microbiology , Amplified Fragment Length Polymorphism Analysis , Australia , Brettanomyces/drug effects , Brettanomyces/genetics , Dekkera/drug effects , Microbial Sensitivity Tests , Phenotype
6.
Appl Microbiol Biotechnol ; 93(3): 1175-84, 2012 Feb.
Article in English | MEDLINE | ID: mdl-21989563

ABSTRACT

The development of new wine yeast strains with improved characteristics is critical in the highly competitive wine market, which faces the demand of ever-changing consumer preferences. Although new strains can be constructed using recombinant DNA technologies, consumer concerns about genetically modified (GM) organisms strongly limit their use in food and beverage production. We have applied a non-GM approach, adaptive evolution with sulfite at alkaline pH as a selective agent, to create a stable yeast strain with enhanced glycerol production; a desirable characteristic for wine palate. A mutant isolated using this approach produced 41% more glycerol than the parental strain it was derived from, and had enhanced sulfite tolerance. Backcrossing to produce heterozygous diploids revealed that the high-glycerol phenotype is recessive, while tolerance to sulfite was partially dominant, and these traits, at least in part, segregated from each other. This work demonstrates the potential of adaptive evolution for development of novel non-GM yeast strains, and highlights the complexity of adaptive responses to sulfite selection.


Subject(s)
Biological Evolution , Food Industry/methods , Glycerol/metabolism , Saccharomyces cerevisiae/physiology , Sulfites/pharmacology , Wine/microbiology , Fermentation , Hydrogen-Ion Concentration , Mutation , Phenotype , Saccharomyces cerevisiae/genetics , Saccharomyces cerevisiae/growth & development , Saccharomyces cerevisiae/metabolism
7.
Appl Microbiol Biotechnol ; 77(1): 145-57, 2007 Nov.
Article in English | MEDLINE | ID: mdl-17846763

ABSTRACT

Surveys conducted worldwide have shown that a significant proportion of grape musts are suboptimal for yeast nutrients, especially assimilable nitrogen. Nitrogen deficiencies are linked to slow and stuck fermentations and sulphidic off-flavour formation. Nitrogen supplementation of grape musts has become common practice; however, almost no information is available on the effects of nitrogen supplementation on wine flavour. In this study, the effect of ammonium supplementation of a synthetic medium over a wide range of nitrogen values on the production of volatile and non-volatile compounds by two high-nitrogen-demand wine fermentation strains of Saccharomyces cerevisiae was determined. To facilitate this investigation, a simplified chemically defined medium that resembles the nutrient composition of grape juice was used. Analysis of variance revealed that ammonium supplementation had significant effects on the concentration of residual sugar, L-malic acid, acetic acid and glycerol but not the ethanol concentration. While choice of yeast strain significantly affected half of the aroma compounds measured, nitrogen concentrations affected 23 compounds, including medium-chain alcohols and fatty acids and their esters. Principal component analysis showed that branched-chain fatty acids and their esters were associated with low nitrogen concentrations, whereas medium-chain fatty esters and acetic acid were associated with high nitrogen concentrations.


Subject(s)
Fermentation , Nitrogen/metabolism , Saccharomyces cerevisiae/metabolism , Wine/microbiology , Acetic Acid/metabolism , Culture Media/chemistry , Culture Media/pharmacology , Esters , Ethanol/metabolism , Fatty Acids/chemistry , Fatty Acids/metabolism , Glycerol/metabolism , Malates/metabolism , Nitrogen/chemistry , Quaternary Ammonium Compounds/chemistry , Quaternary Ammonium Compounds/pharmacology , Saccharomyces cerevisiae/drug effects , Volatilization
8.
Anticancer Res ; 27(4A): 1759-68, 2007.
Article in English | MEDLINE | ID: mdl-17649770

ABSTRACT

The therapeutic opportunities for an improved management of malignant bone disease are currently extensively studied. The conventional management of symptomatic bone lesions in patients with advanced cancer involves various combinations of local and systemic standard anticancer therapies and the symptomatic treatment of skeletal complications. In recent years, bisphosphonates have demonstrated high efficacy to avoid skeletal complications from metastatic bone lesions and to prevent cancer treatment-induced bone loss. Especially in the treatment of patients with bone metastases, secondary to breast cancer, a widespread use of bisphosphonates has been established. With the development of highly potent new-generation bisphosphonates, such as zoledronate, the therapeutic opportunities for bisphosphonates are going to expand. Several current studies have investigated the benefit of zoledronate therapy for bone metastases from a variety of tumor types, including prostate cancer, lung and renal cell cancer and multiple myeloma. Furthermore, bisphosphonates have been shown to significantly reduce antineoplastic therapy-induced bone loss. According to recently published data, it is suggested that bisphosphonates not only play a role in the inhibition of osteoclast-mediated bone resorption, but also have antitumor effects inhibiting tumor cell proliferation, adhesion and invasion, as well as angiogenesis and induction of apoptosis. Further preclinical and clinical investigations are necessary to elucidate the role of bisphosphonates, and large randomized clinical trials should be conducted to confirm the clinical value of bisphosphonates for the prevention of relapse, as well as for the maintainance of net bone density, e.g. during aromatase inhibitor therapy.


Subject(s)
Bone Density Conservation Agents/therapeutic use , Bone Neoplasms/drug therapy , Bone Neoplasms/secondary , Diphosphonates/therapeutic use , Antineoplastic Agents/adverse effects , Clinical Trials as Topic , Humans , Osteoporosis/drug therapy , Osteoporosis/etiology
9.
Lett Appl Microbiol ; 38(4): 315-20, 2004.
Article in English | MEDLINE | ID: mdl-15214732

ABSTRACT

AIMS: Use of microsatellite PCR to monitor populations of Saccharomyces cerevisiae strains during fermentation of grape juice. METHOD AND RESULTS: Six commercial wine strains of S. cerevisiae were screened for polymorphism at the SC8132X locus using a modified rapid PCR identification technique. The strains formed four distinct polymorphic groups that could be readily distinguished from one another. Fermentations inoculated with mixtures of three strains polymorphic at the SC8132X locus were monitored until sugar utilization was complete, and all exhibited a changing population structure throughout the fermentation. CONCLUSIONS: Rapid population quantification demonstrated that wine fermentations are dynamic and do not necessarily reflect the initial yeast population structure. One or more yeast strains were found to dominate at different stages of the fermentation. SIGNIFICANCE AND IMPACT OF THE STUDY: The population structure of S. cerevisiae during mixed culture wine fermentation is dynamic and could modify the chemical composition and flavour profile of wine.


Subject(s)
Fermentation , Food Microbiology , Microsatellite Repeats , Saccharomyces cerevisiae/growth & development , Saccharomyces cerevisiae/genetics , Wine/microbiology , Carbohydrate Metabolism , Colony Count, Microbial , Polymorphism, Genetic , Saccharomyces cerevisiae/metabolism
10.
Int J Biol Markers ; 19(1): 1-13, 2004.
Article in English | MEDLINE | ID: mdl-15077921

ABSTRACT

BACKGROUND: HER-2/neu positivity is required for the selection of stage IV breast cancer patients for trastuzumab therapy. We compared the results of the recommended immunohistochemistry (IHC) evaluation with the automated ACIS IHC system and with fluorescence in situ hybridization (FISH). These HER-2/neu tissue results were correlated with the serum HER-2/neu (sHER-2/neu) levels at the time of metastatic spread. PATIENTS AND METHODS: A total of 61 IHC slides from 30 patients were stained using the HercepTest. HER-2/neu gene amplification was determined using the Ventana FISH assay. sHER-2/neu levels were measured with the Oncogene Science" ELISA kit. The concordance of HER-2/neu results was determined using the concordance index Kappa (kappa). RESULTS: The best concordance between any IHC and FISH was found for the automated ACIS system (88.5%, kappa=0.68, category "good"). The comparison between the manual interpretations and the automated IHC was categorized as "very good" (95.1%, kappa=0.85). The median sHER-2/neu level of FISH positive patients was significantly higher (67 ng/mL) than that of FISH negative patients (17 ng/mL, p=0.018). The increase in HER-2/neu positivity comparing tissue to stage IV serum was statistically significant (p=0.001). CONCLUSIONS: The concordance between conventional IHC and computerized analysis was very good. The number of patients with stage IV breast cancer with an elevated sHER-2/neu level was much higher than HER-2/neu positivity in tissue. This discrepancy is only partially explained by the influence of tumor load. Patients with an elevated sHER-2/neu level and no tissue overexpression should be considered for retesting of tissue or a new biopsy.


Subject(s)
Biomarkers, Tumor/blood , Breast Neoplasms/diagnosis , Breast Neoplasms/genetics , Genetic Predisposition to Disease , Mass Screening/methods , Mass Screening/standards , Receptor, ErbB-2/blood , Receptor, ErbB-2/genetics , Biomarkers, Tumor/biosynthesis , Disease Progression , Enzyme-Linked Immunosorbent Assay , Humans , Immunohistochemistry , In Situ Hybridization, Fluorescence , Reproducibility of Results , Time Factors
11.
Anticancer Res ; 23(2A): 991-7, 2003.
Article in English | MEDLINE | ID: mdl-12820337

ABSTRACT

INTRODUCTION: Tyrosine kinase signal transduction pathways are a focus of interest for therapeutic interventions. The oncoprotein HER-2/neu shows tyrosine kinase activity leading to phosphorylation and activation of numerous second-messenger systems. One target of phosphorylation processes is assumed to be the tumor type M2 isoenzyme of pyruvate kinase (TuM2-PK) which has been shown to be elevated in metastatic breast cancer. MATERIALS AND METHODS: We measured the plasma levels of HER-2/neu, TuM2-PK and tyrosine-phosphorylated TuM2-PK (p-TuM2-PK) in 69 patients (pts) with breast cancer and correlated these parameters to each other and to the classical tumor marker CA 27.29. The samples were measured with ELISA assays while CA 27.29 was determined with an automated chemiluminescence assay. For analysis, we formed 5 subgroups according to the plasma HER-2/neu levels (group 1: < 15 ng/ml, n = 28; group 2: 15 < or = x < 50 ng/ml, n = 21; group 3: 50 < or = x < 100 ng/ml, n = 9; group 4: 100 < or = x < 500 ng/ml, n = 7; group 5: > or = 500 ng/ml, n = 4). RESULTS: From the HER-2/neu group 1 to group 5, there was a statistically significant increase of CA 27.29 from 35.8 U/ml to 1095.8 U/ml (p < 0.001). There was also a trend for increasing TuM2-PK levels with increasing HER-2/neu levels (p = 0.126). From the lowest extinction (0.088) to the highest extinction result (2.167) of p-TuM2-PK we found a 25-fold increase, which was reproducible in spiking and dilution experiments proving that TuM2-PK is phosphorylated at tyrosine residues to a certain extent. However, there was no correlation between plasma HER-2/neu and p-TuM2-PK levels. CONCLUSION: TuM2-PK is phosphorylated at tyrosine residues in breast cancer patients. Using the shed antigen of HER-2/neu in plasma as a surrogate marker, we did not find any evidence that this phosphorylation is initiated by the oncoprotein HER-2/neu.


Subject(s)
Breast Neoplasms/pathology , Phosphotyrosine/blood , Pyruvate Kinase/blood , Receptor, ErbB-2/blood , Adult , Aged , Antigens, Tumor-Associated, Carbohydrate/blood , Biomarkers, Tumor/blood , Breast Neoplasms/blood , Female , Humans , Isoenzymes/blood , Middle Aged , Neoplasm Staging , Protein-Tyrosine Kinases/blood , Receptors, Estrogen/analysis , Receptors, Progesterone/analysis
12.
Lett Appl Microbiol ; 36(5): 307-14, 2003.
Article in English | MEDLINE | ID: mdl-12680944

ABSTRACT

AIMS: To determine the bacterial species associated with an outbreak of spoilage in commercially bottled red wine where the bottles had been stored in an upright vertical compared with horizontal position. METHODS AND RESULTS: Bottled wines comprising Cabernet Sauvignon, Pinot Noir, Shiraz, Merlot and blended red varieties were examined for visible spoilage. Analysis of visibly affected and non-affected wines revealed a spectrum of aroma and flavour defects, ranging from loss of fruity aroma, staleness, oxidized character to overt volatile acidity. Only acetic acid bacteria, and not yeast or lactic acid bacteria, could be isolated from both spoiled and unspoiled wines and were found to grow only on Wallerstein Nutrient (WL) medium supplemented with 10% red wine or 1-2% ethanol. Analysis of the 16S rRNA region and RAPD-PCR analysis showed the isolates to be a closely related group of Acetobacter pasteurianus, but this group was differentiated from the group comprising beer, vinegar and cider strains. CONCLUSIONS: A. pasteurianus was the species considered responsible for the spoilage but the isolates obtained had atypical properties for this species. In particular, they failed to grow on WL nutrient medium without ethanol or wine supplementation. Storage of the bottles of wine containing A. pasteurianus in an upright vertical position specifically induced growth and spoilage in a proportion of the bottles under conditions that were inhibitory for horizontally stored bottles. We hypothesize that the upright position created a heterogeneous environment that allowed the growth of bacteria in only those bottles sealed with cork closures that had upper limit for the natural permeability to oxygen. Such a heterogeneous environment would not exist in horizontally stored bottles as the larger volume of wine adjacent to the cork would strongly compete with the bacteria for the oxygen as it diffuses through the cork closure. SIGNIFICANCE AND IMPACT OF THE STUDY: A low level of bacteria (acetic acid bacteria) in wine can proliferate and cause wine spoilage in bottles stored in an upright vertical as opposed to an horizontal position under conditions that would normally limit bacterial development.


Subject(s)
Acetobacter/isolation & purification , Food Microbiology , Wine/microbiology , Acetic Acid/metabolism , Acetobacter/classification , Acetobacter/metabolism , Colony Count, Microbial , Fermentation , Hydrogen-Ion Concentration , Phylogeny , Temperature
13.
Am J Perinatol ; 18(6): 313-24, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11607849

ABSTRACT

The objective of this study is to determine the plasma concentrations and diagnostic accuracy of interleukin-6 (IL-6) and interleukin-8 (IL-8) in newborn infection. One hundred and one newborn infants with clinical signs of infection during their primary hospitalization were investigated with the minimum of a blood culture, C-reactive protein (CRP), full blood examination (FBE), and cytokine concentrations (IL-6 and IL-8). Infection in infants was classified without knowledge of cytokine levels into four groups-definite (n = 11), probable (n = 12), uncertain (n = 52), and nil (n = 26). The median concentrations of IL-6 and IL-8 were significantly higher in the definitely infected group compared with the other three groups (p <0.05). At the cut-off concentration of highest accuracy, IL-6 (>175 pg/mL) and IL-8 (>28 pg/mL) had similar sensitivities (80 and 82%, respectively) and specificities (91 and 81%, respectively). Cut-off concentrations could be identified with improved sensitivities (90% for IL-6 and 100% for IL-8) that maintained specificity >50%. However, the confidence intervals were wide for all sensitivities and specificities. IL-6 and IL-8 had little diagnostic accuracy in infants with probable infection. IL-6 and IL-8 concentrations increase early in newborn infants with definite infection.


Subject(s)
Interleukin-6/blood , Interleukin-8/blood , Sepsis/diagnosis , C-Reactive Protein/analysis , Female , Humans , Infant, Newborn , Male , ROC Curve , Sensitivity and Specificity
14.
J Appl Microbiol ; 89(3): 381-9, 2000 Sep.
Article in English | MEDLINE | ID: mdl-11021569

ABSTRACT

Fourteen killer yeasts were assayed for their ability to kill species of yeast that are commonly associated with fermenting grape must and wine. A total of 147 of a possible 364 killer-sensitive interactions were observed at pH 4.5. Of the killer yeasts studied, Pichia anomala NCYC 434 displayed the broadest killing range. At a pH value comparable with those of wine ferments, pH 3.5, the incidence of killer-sensitive interactions was reduced by 700% across all the yeasts. Williopsis saturnus var. mrakii CBS 1707 exhibited the broadest killing range at the lower pH, killing more than half of the tester strains. Intraspecific variation in sensitivity to killer yeasts was observed in all species where more than one strain was tested. Also, in strains of Pichia anomala, Kluyveromyces lactis and Pichia membranifaciens, the three species in which more than one killer yeast was analysed, intraspecific variation in killer activity was observed.


Subject(s)
Wine/microbiology , Yeasts/physiology , Antibiosis , Fermentation , Hydrogen-Ion Concentration , Kluyveromyces/physiology , Pichia/physiology , Saccharomyces cerevisiae/physiology , Yeasts/growth & development
15.
J Paediatr Child Health ; 36(3): 262-4, 2000 Jun.
Article in English | MEDLINE | ID: mdl-10849229

ABSTRACT

OBJECTIVES: Illicit drug taking in Australia, with its attendant social and medical consequences, is increasing and the effects extend to maternity hospitals where infants born to addicted mothers have more health problems in the neonatal period. The aims of this study were to evaluate (1) the patterns of illness of such infants and (2) the burden imposed on the neonatal department of a large tertiary maternity centre. METHODOLOGY: An audit was conducted of all Chemical Dependency Unit (CDU) mothers and babies delivered at the Royal Women's Hospital, Melbourne, Australia during 1997. Data were compared with those from a concurrent control group of mothers and babies randomly generated from the hospital's obstetric database. RESULTS: Ninety-six infants born to CDU mothers were compared with a control group of 200 infant/mother pairs. The majority of women in the CDU clinic were treated for narcotic addiction with methadone (90%) but most continued to use heroin during pregnancy (68%). Infants born to CDU mothers were significantly less mature and lighter than control infants. Fifty-three (55%) CDU infants required admission to the Special Care Nursery either because of neonatal abstinence syndrome (n = 29) or other medical reasons (n = 24). The median length of hospital stay was significantly longer in CDU compared with control infants (8 vs 3 days, P < 0.01). CONCLUSIONS: Infants born to drug dependent mothers have more neonatal problems requiring specialized medical and nursing expertise, compared with control infants. These infants are large consumers of scarce health resources.


Subject(s)
Health Resources/economics , Infant, Newborn, Diseases/epidemiology , Pregnancy Complications/epidemiology , Prenatal Exposure Delayed Effects , Substance-Related Disorders/economics , Substance-Related Disorders/epidemiology , Adult , Ambulatory Care Facilities , Amphetamines , Australia , Benzodiazepines , Cannabis , Cocaine , Comorbidity , Female , Heroin , Hospitals, Urban , Humans , Incidence , Infant, Newborn , Infant, Newborn, Diseases/chemically induced , Infant, Newborn, Diseases/therapy , Length of Stay/economics , Length of Stay/statistics & numerical data , Lysergic Acid Diethylamide , Male , Maternal-Fetal Exchange , Medical Audit , Methadone , Pregnancy , Pregnancy Complications/economics
16.
Arch Toxicol ; 73(10-11): 607-10, 2000 Jan.
Article in English | MEDLINE | ID: mdl-10663393

ABSTRACT

Incubation of the o-phenylphenol (OPP) metabolites, o-phenylhydroquinone (PHQ) and o-phenylbenzoquinone (PBQ) with V 79 Chinese hamster cells led to a significant enhancement of the amount of 8-hydroxy-2'-deoxyguanosine (8-OH-dG) in nuclear DNA. With OPP no distinct induction of this lesion could be observed. In addition, PHQ and PBQ were able to generate DNA single-strand breaks (DNA SSB), while OPP failed to induce this lesion. All incubations were performed for 1 h without exogenous metabolic activations and the lowest effective concentration tested was 20 microM. It is concluded that these metabolites may contribute to the carcinogenicity of OPP and sodium o-phenylphenolate (SOPP) observed in rats, by generating reactive oxygen species (ROS) through their redox cycling properties.


Subject(s)
Benzoquinones/toxicity , Biphenyl Compounds/toxicity , DNA Damage , Fibroblasts/drug effects , Fungicides, Industrial/metabolism , Fungicides, Industrial/toxicity , Hydroquinones/toxicity , 8-Hydroxy-2'-Deoxyguanosine , Animals , Benzoquinones/metabolism , Biphenyl Compounds/metabolism , Carcinogens/metabolism , Carcinogens/toxicity , Cell Survival/drug effects , Cells, Cultured/cytology , Cells, Cultured/drug effects , Cells, Cultured/metabolism , Cricetinae , Cricetulus , DNA Adducts/biosynthesis , DNA, Single-Stranded/drug effects , Deoxyguanosine/analogs & derivatives , Deoxyguanosine/biosynthesis , Fibroblasts/cytology , Fibroblasts/metabolism , Hydroquinones/metabolism , Reactive Oxygen Species/metabolism
17.
Int J Syst Bacteriol ; 49 Pt 2: 915-24, 1999 Apr.
Article in English | MEDLINE | ID: mdl-10319518

ABSTRACT

Amplified fragment length polymorphism (AFLP) was used to investigate genetic variation in commercial strains, type strains and winery isolates from a number of yeast species. AFLP was shown to be effective in discriminating closely related strains. Furthermore, sufficient similarity in the fingerprints produced by yeasts of a given species allowed classification of unknown isolates. The applicability of the method for determining genome similarities between yeasts was investigated by performing cluster analysis on the AFLP data. Results from two species, Saccharomyces cerevisiae and Dekkera bruxellensis, illustrate that AFLP is useful for the study of intraspecific genetic relatedness. The value of the technique in strain differentiation, species identification and the analysis of genetic similarity demonstrates the potential of AFLP in yeast ecology and evolutionary studies.


Subject(s)
DNA Fingerprinting/methods , Genetic Variation , Polymorphism, Restriction Fragment Length , Yeasts/classification , Cluster Analysis , DNA, Fungal/genetics , Polymerase Chain Reaction/methods , Species Specificity , Yeasts/genetics
18.
Arch Dis Child Fetal Neonatal Ed ; 79(1): F54-7, 1998 Jul.
Article in English | MEDLINE | ID: mdl-9797626

ABSTRACT

AIM: To determine whether extubation to nasal continuous airway pressure (NCPAP) results in a greater proportion of infants remaining free of additional ventilatory support for one week after extubation compared with those extubated directly to headbox oxygen. METHODS: A randomised, controlled, clinical trial was conducted at the neonatal intensive care unit of the Royal Women's Hospital, Melbourne, of infants with birthweights between 600 and 1250 g, ventilated via an endotracheal tube for more than 12 hours, requiring less than 50% oxygen, a ventilator rate < or = 20/minute, considered by the clinical management team to be ready for extubation. Infants were randomly allocated either to NCPAP or to oxygen administered via a headbox. Success was defined by no requirement for additional ventilatory support over the week following extubation. Failure criteria were (i) apnoea; (ii) absolute increase in oxygen requirement greater than 15% above than required before extubation; or (iii) respiratory acidosis (pH < 7.25 with pCO2 > 6.67 kPa). RESULTS: Thirty one of 47 (66%) infants were successfully extubated to NCPAP compared with 18 of 45 (40%) for headbox oxygen. The increase in failure rate in the headbox group was due primarily to increased oxygen requirements in this group. Of the 27 who failed headbox oxygen, 26 were given a trial of NCPAP and 13 did not require endotracheal reintubation. There was no significant difference between the groups in the total number of days of assisted ventilation or the duration of inpatient stay. CONCLUSIONS: NCPAP applied prophylactically after endotracheal extubation reduces the incidence of adverse clinical events that lead to failure of extubation in the seven days after extubation. This reduction is clinically important. The benefits of NCPAP do not seem to be associated with an increased incidence of unwanted side effects.


Subject(s)
Infant, Very Low Birth Weight , Positive-Pressure Respiration , Ventilator Weaning/methods , Female , Humans , Infant, Newborn , Male , Oxygen/therapeutic use , Treatment Outcome
19.
Int J Syst Bacteriol ; 48 Pt 1: 279-86, 1998 Jan.
Article in English | MEDLINE | ID: mdl-9542098

ABSTRACT

A PCR-based method has been developed that permits both intraspecies differentiation and species identification of yeast isolates. Oligonucleotide primers that are complementary to intron splice sites were used to produce PCR fingerprints that display polymorphisms between different species of indigenous wine yeasts. Although polymorphisms existed between isolates of the same species, the banding patterns shared several amplification products that allowed species identification. Importantly, the method was able to distinguish between species of the closely related Saccharomyces sensu stricto yeasts. In two cases where isolates could not be positively identified there was discrepancy between the phenetic and phylogenetic species concept. The method has applications in yeast ecological studies, enabling the rapid grouping of isolates with related genomes and the investigation of population dynamics of strains of the same species.


Subject(s)
DNA, Fungal/analysis , Polymerase Chain Reaction/methods , Saccharomyces cerevisiae/genetics , Saccharomyces cerevisiae/isolation & purification , Wine/microbiology , DNA Fingerprinting , DNA Primers , Molecular Sequence Data , Phenotype , Phylogeny , Species Specificity
20.
J Qual Clin Pract ; 17(3): 131-6, 1997 Sep.
Article in English | MEDLINE | ID: mdl-9343790

ABSTRACT

To examine the patterns of use of patient restraints in Australian hospitals and the level of adherence to accepted guidelines, we undertook a point-prevalence study in four teaching hospitals in three different States. This involved ward inspections and review of case notes. Overall, 51 (12.5%) of the 408 people audited were being restrained with a variety of physical and chemical agents. The rate of restraint use varied from 8.5% to 18.5% between hospitals. Although the overall prevalence of restraint use increased with age, the hospital with the oldest patients used restraints least. At all hospitals, there was scant documentation in the case notes concerning the use of restraints. The prevalence of restraint use varies widely in different hospitals. As this is not explained by the patient profile, it probably reflects different philosophies of care. Documentation of the use of restraints needs to be improved in all the centres studied.


Subject(s)
Guideline Adherence , Hospitals, Teaching/standards , Restraint, Physical , Adolescent , Adult , Aged , Aged, 80 and over , Decision Making , Documentation/standards , Female , Humans , Male , Medical Audit , Middle Aged , New South Wales , Organizational Policy , Quality Assurance, Health Care , South Australia , Tasmania
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