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1.
Ultrasound Q ; 37(3): 272-277, 2021 Sep 01.
Article in English | MEDLINE | ID: mdl-34478427

ABSTRACT

ABSTRACT: To determine if lung to liver MR T2 signal ratio is predictive of neonatal outcome in fetuses with congenital diaphragmatic hernia (CDH).After Interal Review Board approval, the PACS systems at the University of Washington and University of Utah were searched for cases having an in utero fetal MR examination diagnostic of CDH. Inclusion criteria were at least 1 prior ultrasound demonstrating a CDH and an MR obtained within 1 week of that prior ultrasound.A total of 69 patients from the University of Utah and 13 from the University of Washington satisfied the inclusion criteria for a total of 82. After adjusting for gestational age and contralateral lung volume, there was little apparent association between contralateral lung to liver MR T2 signal and 5-minute Apgar score and neonatal mortality When considering neonatal Apgar and mortality, increasing contralateral lung volume was significantly associated with lower risk (hazard ratio, 0.40 per doubling; 95% confidence interval, 0.24-0.69; P = 0.001) as expected.Our data demonstrate that the lung to liver MR signal ratio was not predictive of outcome. The measurement of contralateral lung area, and gestational age at the time of the examination (time of diagnosis) are still the best predictors of poor neonatal outcome.


Subject(s)
Hernias, Diaphragmatic, Congenital , Female , Fetus , Gestational Age , Hernias, Diaphragmatic, Congenital/diagnostic imaging , Humans , Infant, Newborn , Lung/diagnostic imaging , Magnetic Resonance Imaging , Magnetic Resonance Spectroscopy , Pregnancy , Ultrasonography, Prenatal
2.
J Am Coll Radiol ; 18(5S): S189-S198, 2021 May.
Article in English | MEDLINE | ID: mdl-33958112

ABSTRACT

The Appropriateness Criteria for the imaging screening of second and third trimester fetuses for anomalies are presented for fetuses that are low risk, high risk, have had soft markers detected on ultrasound, and have had major anomalies detected on ultrasound. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.


Subject(s)
Diagnostic Imaging , Societies, Medical , Female , Humans , Pregnancy , Pregnancy Trimester, Third , Research , Ultrasonography , United States
3.
J. Am. Coll. Radiol ; 18(supl. 5): [10], May 1, 2021. tab
Article in English | BIGG - GRADE guidelines | ID: biblio-1255337

ABSTRACT

The Appropriateness Criteria for the imaging screening of second and third trimester fetuses for anomalies are presented for fetuses that are low risk, high risk, have had soft markers detected on ultrasound, and have had major anomalies detected on ultrasound. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.


Subject(s)
Humans , Female , Pregnancy , Congenital Abnormalities/diagnostic imaging , Ultrasonography, Prenatal
5.
J Am Coll Radiol ; 17(11S): S447-S458, 2020 Nov.
Article in English | MEDLINE | ID: mdl-33153556

ABSTRACT

A fetus with an increased nuchal translucency at 11 to 14 weeks gestation is at risk for aneuploidy, genetic syndromes, structural anomalies, and intrauterine fetal demise in both single and twin gestations. In addition to referral to genetics for counseling and consideration of diagnostic genetic testing, a detailed anatomic survey and fetal echocardiogram are indicated in the second trimester to screen for congenital malformations and major heart defects. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.


Subject(s)
Nuchal Translucency Measurement , Societies, Medical , Diagnostic Imaging , Evidence-Based Medicine , Female , Humans , Pregnancy , United States
6.
J Am Coll Radiol ; 17(11S): S497-S504, 2020 Nov.
Article in English | MEDLINE | ID: mdl-33153560

ABSTRACT

Vaginal bleeding can occur throughout pregnancy with varied etiologies. Although history and physical examination can identify many etiologies, imaging, in particular ultrasound (US), is the backbone of current medical practice. US pregnant uterus transabdominal, US pregnant uterus transvaginal, and US duplex Doppler velocimetry are usually appropriate for the evaluation of women with painless vaginal bleeding, those with painful vaginal bleeding, and also for those with second or third trimester vaginal bleeding with suspicion of or known placenta previa, low-lying placenta, or vasa previa. US cervix transperineal may be appropriate for those with painless or painful vaginal bleeding but is usually not appropriate for second or third trimester vaginal bleeding with suspicion of or known placenta previa, low-lying placenta, or vasa previa. Because the outcome of pregnancies is unequivocally related to the specific etiology of the vaginal bleeding, knowledge of imaging results directly informs patient management to optimize the outcome for mother and fetus. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.


Subject(s)
Societies, Medical , Uterine Hemorrhage , Diagnostic Imaging , Female , Humans , Pregnancy , Pregnancy Trimester, Third , Ultrasonography , United States , Uterine Hemorrhage/diagnostic imaging , Uterine Hemorrhage/etiology
7.
J Am Coll Radiol ; 17(5S): S26-S35, 2020 May.
Article in English | MEDLINE | ID: mdl-32370970

ABSTRACT

Preterm birth remains the leading cause of perinatal morbidity and mortality. Although the greatest risk factor for preterm birth is a history of prior preterm birth, a short cervical length (≤25 mm) before 24 weeks' gestational age is also associated with increased risk of spontaneous preterm delivery. As such, cervical length assessment has become of particular interest in predicting those patients at risk for preterm birth. Other clinical scenarios (eg, preterm labor, induction of labor, and active labor) may arise, in which assessment of the cervix may be of interest. Ultrasound is the mainstay imaging modality for assessing the gravid cervix, with transvaginal ultrasound recommended in patients at high risk for preterm birth or suspected preterm labor. Transperineal ultrasound is an alternate approach in those cases where transvaginal ultrasound in contraindicated. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.


Subject(s)
Cervix Uteri , Premature Birth , Cervix Uteri/diagnostic imaging , Diagnostic Imaging , Female , Humans , Infant, Newborn , Pregnancy , Premature Birth/diagnostic imaging , Societies, Medical , United States
8.
J Am Coll Radiol ; 16(5S): S116-S125, 2019 May.
Article in English | MEDLINE | ID: mdl-31054738

ABSTRACT

Fetal growth restriction, or an estimated fetal weight of less than the 10th percentile, is associated with adverse perinatal outcome. Optimizing management for obtaining the most favorable outcome for mother and fetus is largely based on detailed ultrasound findings. Identifying and performing those ultrasound procedures that are most associated with adverse outcome is necessary for proper patient management. Transabdominal ultrasound is the mainstay of initial management and assessment of fetal growth. For those fetuses that are identified as small for gestational age, assessment of fetal well-being with biophysical profile and Doppler velocimetry provide vital information for differentiating those fetuses that may be compromised and may require delivery and those that are well compensated. Delivery of the pregnancy is primarily based upon the gestational age of the pregnancy and the ultrasound findings. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.


Subject(s)
Fetal Growth Retardation/diagnostic imaging , Ultrasonography, Prenatal/methods , Contrast Media , Diagnosis, Differential , Evidence-Based Medicine , Female , Humans , Pregnancy , Societies, Medical , United States
9.
J Am Coll Radiol ; 15(11S): S365-S372, 2018 Nov.
Article in English | MEDLINE | ID: mdl-30392605

ABSTRACT

Pelvic pain is common in both reproductive age and postmenopausal women, and the major etiologies change throughout the life cycle. Chronic pain is defined as lasting for at least 6 months. There are many gastrointestinal and urinary disorders associated with chronic pain in this age group, which are not discussed in this guideline. Pain may be localized to the deep pelvis, with potential causes including pelvic congestion syndrome, intraperitoneal adhesions, hydrosalpinx, chronic inflammatory disease, or cervical stenosis. Ultrasound is the initial imaging modality of choice, while CT and MRI may be appropriate for further characterization of sonographic findings. Alternatively, pain may be localized to the vagina, vulva, or perineum, with potential causes including vaginal atrophy, vaginismus, vaginal or vulvar cysts, vulvodynia, or pelvic myofascial pain. Imaging is primarily indicated in context of an abnormal physical exam and ultrasound is the initial modality of choice, while MRI may be appropriate for further characterization in select cases. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.


Subject(s)
Chronic Pain/diagnostic imaging , Pelvic Pain/diagnostic imaging , Postmenopause , Aged , Chronic Pain/etiology , Diagnosis, Differential , Evidence-Based Medicine , Female , Humans , Middle Aged , Pain Management , Pelvic Pain/etiology , Societies, Medical , United States
10.
Obstet Gynecol Surv ; 72(6): 377-392, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28661551

ABSTRACT

IMPORTANCE: The prevalence of uterine malformations has been reported in up to 7% of the general population and 18% of those with recurrent pregnancy loss. The diagnosis, classification, management, and outcome of the management have been subject to debate for decades. OBJECTIVE: The aim of this article is to summarize the current knowledge regarding the genetics of müllerian anomalies, the varied classification schemes, the appropriate diagnostic modalities, the surgical methods, and the obstetric outcomes related to these surgical methods. EVIDENCE ACQUISITION: An extensive literature review using the key words uterine anomaly, classification, mullerian, agenesis, unicornuate, didelphys, bicornuate, septate, arcuate, DES, and diethyl stilbestrol was conducted using PubMed. Only English-language publications were reviewed. Relevant references within these publications were also obtained and reviewed in preparing this article. CONCLUSIONS: Current evidence favors continued use of the American Society of Reproductive Medicine classification. Three-dimensional sonography, especially when combined with saline infusion, can be very helpful in accurately classifying müllerian anomalies. RELEVANCE: Müllerian anomalies are relatively common. Accurate knowledge of the advantages and limitations of various diagnostic modalities, the limitations of the classification systems, the surgical options available where appropriate, and the obstetric outcomes after these surgeries will help in the optimal management of these patients.


Subject(s)
Mullerian Ducts/abnormalities , Urogenital Abnormalities/classification , Uterus/abnormalities , Female , Humans , Magnetic Resonance Imaging , Outcome Assessment, Health Care , Pregnancy , Pregnancy Outcome , Syndrome , Ultrasonography , Urogenital Abnormalities/diagnosis , Urogenital Abnormalities/therapy
11.
Obstet Gynecol ; 111(1): 15-21, 2008 Jan.
Article in English | MEDLINE | ID: mdl-18165388

ABSTRACT

OBJECTIVE: To estimate whether the position of the catheter placement into either the uterus or cervix during the saline infusion sonohysterography affected the magnitude of pain. METHODS: A clinical trial was conducted with women undergoing saline infusion sonohysterogram randomized to intracervical or intrauterine balloon catheter placement. The primary outcome end points were the degrees of pain experienced after initial inflation and then after deflation of the balloon catheter at the completion of the saline infusion sonohysterogram. Pain was quantified with a 10-point visual analog pain scale. Secondary end points included total time for the saline infusion sonohysterogram and the total volume of infused saline necessary for adequate visualization of the endometrial cavity. RESULTS: Thirty-five patients were randomly assigned to intracervical balloon placement and 34 to intrauterine placement. After initial inflation there was significantly less pain with intracervical than intrauterine balloon placement (1.8 compared with 3.0, P=.02), although there was no difference in pain at the end of the procedure after deflation of the balloon (P=.66). Significantly less infused saline was required with intracervical catheter placement (19 mL compared with 40 mL, P=.001). Nulliparous women had significantly more pain than did parous women, both after initial balloon inflation and at completion of the saline infusion sonohysterogram (P<.05). CONCLUSION: Intracervical catheter placement results in significantly less pain during an saline infusion sonohysterography and also requires half the saline volume to perform the saline infusion sonohysterogram. Therefore, routine intracervical balloon placement should be considered for saline infusion sonohysterogram. TRIAL REGISTRATION: ClinicalTrials.Gov, www.clinicaltrials.gov, NCT00534963 LEVEL OF EVIDENCE: I.


Subject(s)
Uterine Diseases/diagnostic imaging , Uterus/diagnostic imaging , Adult , Female , Humans , Middle Aged , Pain/etiology , Pain Measurement , Sodium Chloride , Ultrasonography/adverse effects , Ultrasonography/methods
12.
Int J Food Microbiol ; 125(1): 79-90, 2008 Jun 30.
Article in English | MEDLINE | ID: mdl-17920717

ABSTRACT

Amplification of repetitive bacterial DNA elements through the polymerase chain reaction (rep-PCR fingerprinting) using the (GTG)(5) primer, referred to as (GTG)(5)-PCR fingerprinting, was found a promising genotypic tool for rapid and reliable speciation of acetic acid bacteria (AAB). The method was evaluated with 64 AAB reference strains, including 31 type strains, and 132 isolates from Ghanaian, fermented cocoa beans, and was validated with DNA:DNA hybridization data. Most reference strains, except for example all Acetobacter indonesiensis strains and Gluconacetobacter liquefaciens LMG 1509, grouped according to their species designation, indicating the usefulness of this technique for identification to the species level. Moreover, exclusive patterns were obtained for most strains, suggesting that the technique can also be used for characterization below species level or typing of AAB strains. The (GTG)(5)-PCR fingerprinting allowed us to differentiate four major clusters among the fermented cocoa bean isolates, namely A. pasteurianus (cluster I, 100 isolates), A. syzygii- or A. lovaniensis-like (cluster II, 23 isolates), and A. tropicalis-like (clusters III and IV containing 4 and 5 isolates, respectively). A. syzygii-like and A. tropicalis-like strains from cocoa bean fermentations were reported for the first time. Validation of the method and indications for reclassifications of AAB species and existence of new Acetobacter species were obtained through 16S rRNA sequencing analyses and DNA:DNA hybridizations. Reclassifications refer to A. aceti LMG 1531, Ga. xylinus LMG 1518, and Ga. xylinus subsp. sucrofermentans LMG 18788(T).


Subject(s)
Acetic Acid/metabolism , Acetobacter/classification , Acetobacter/isolation & purification , Cacao/microbiology , Ethanol/metabolism , Phylogeny , Acetobacter/metabolism , Bacterial Typing Techniques , DNA Fingerprinting , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , Fermentation , Food Microbiology , Gene Amplification , Molecular Sequence Data , RNA, Ribosomal, 16S/chemistry , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA
13.
Appl Environ Microbiol ; 74(1): 86-98, 2008 Jan.
Article in English | MEDLINE | ID: mdl-17993565

ABSTRACT

The influence of turning and environmental contamination on six spontaneous cocoa bean heap fermentations performed in Ghana was studied through a multiphasic approach, encompassing both microbiological (culture-dependent and culture-independent techniques) and metabolite target analyses. A sensory analysis of chocolate made from the fermented, dried beans was performed as well. Only four clusters were found among the isolates of acetic acid bacteria (AAB) identified: Acetobacter pasteurianus, Acetobacter ghanensis, Acetobacter senegalensis, and a potential new Acetobacter lovaniensis-like species. Two main clusters were identified among the lactic acid bacteria (LAB) isolated, namely, Lactobacillus plantarum and Lactobacillus fermentum. No differences in biodiversity of LAB and AAB were seen for fermentations carried out at the farm and factory sites, indicating the cocoa pod surfaces and not the general environment as the main inoculum for spontaneous cocoa bean heap fermentation. Turning of the heaps enhanced aeration and increased the relative population size of AAB and the production of acetic acid. This in turn gave a more sour taste to chocolate made from these beans. Bitterness was reduced through losses of polyphenols and alkaloids upon fermentation and cocoa bean processing.


Subject(s)
Acetobacter/isolation & purification , Biodiversity , Cacao/microbiology , Lactobacillus plantarum/isolation & purification , Limosilactobacillus fermentum/isolation & purification , Acetic Acid/metabolism , Acetobacter/classification , Acetobacter/genetics , Acetobacter/metabolism , Cacao/chemistry , Cacao/metabolism , Cluster Analysis , DNA Fingerprinting , DNA, Bacterial/genetics , Fermentation , Ghana , Lactic Acid/metabolism , Limosilactobacillus fermentum/classification , Limosilactobacillus fermentum/genetics , Limosilactobacillus fermentum/metabolism , Lactobacillus plantarum/classification , Lactobacillus plantarum/genetics , Lactobacillus plantarum/metabolism , Taste
14.
Int J Syst Evol Microbiol ; 57(Pt 7): 1647-1652, 2007 Jul.
Article in English | MEDLINE | ID: mdl-17625210

ABSTRACT

Twenty-three acetic acid bacteria, isolated from traditional heap fermentations of Ghanaian cocoa beans, were subjected to a polyphasic taxonomic study. The isolates were catalase-positive, oxidase-negative, Gram-negative rods. They oxidized ethanol to acetic acid and were unable to produce 2-ketogluconic acid, 5-ketogluconic acid and 2,5-diketogluconic acid from glucose; therefore, they were tentatively identified as Acetobacter species. 16S rRNA gene sequencing and phylogenetic analysis confirmed their position in the genus Acetobacter, with Acetobacter syzygii and Acetobacter lovaniensis as their closest phylogenetic neighbours. (GTG)(5)-PCR fingerprinting grouped the strains in a cluster that did not contain any type strains of members of the genus Acetobacter. DNA-DNA hybridization with the type strains of all recognized Acetobacter species revealed DNA-DNA relatedness values below the species level. The DNA G+C contents of three selected strains were 56.9-57.3 mol%. The novel strains had phenotypic characteristics that enabled them to be differentiated from phylogenetically related Acetobacter species, i.e. they were motile, did not produce 2-ketogluconic acid or 5-ketogluconic acid from glucose, were catalase-positive and oxidase-negative, grew on yeast extract with 30 % glucose, grew on glycerol (although weakly) but not on maltose or methanol as carbon sources, and did not grow with ammonium as sole nitrogen source and ethanol as carbon source. Based on the genotypic and phenotypic data, the isolates represent a novel species of the genus Acetobacter for which the name Acetobacter ghanensis sp. nov. is proposed. The type strain is R-29337(T) (=430A(T)=LMG 23848(T)=DSM 18895(T)).


Subject(s)
Acetic Acid/metabolism , Acetobacter/classification , Acetobacter/isolation & purification , Cacao/microbiology , Acetobacter/chemistry , Acetobacter/physiology , Bacterial Typing Techniques , Base Composition , Catalase/analysis , DNA Fingerprinting , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , Ethanol/metabolism , Fermentation , Food Microbiology , Genes, rRNA , Glucose/metabolism , Locomotion , Molecular Sequence Data , Nucleic Acid Hybridization , Oxidation-Reduction , Oxidoreductases/analysis , Phylogeny , Polymerase Chain Reaction/methods , RNA, Bacterial/genetics , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA , Sequence Homology, Nucleic Acid
15.
Appl Environ Microbiol ; 73(6): 1809-24, 2007 Mar.
Article in English | MEDLINE | ID: mdl-17277227

ABSTRACT

The Ghanaian cocoa bean heap fermentation process was studied through a multiphasic approach, encompassing both microbiological and metabolite target analyses. A culture-dependent (plating and incubation, followed by repetitive-sequence-based PCR analyses of picked-up colonies) and culture-independent (denaturing gradient gel electrophoresis [DGGE] of 16S rRNA gene amplicons, PCR-DGGE) approach revealed a limited biodiversity and targeted population dynamics of both lactic acid bacteria (LAB) and acetic acid bacteria (AAB) during fermentation. Four main clusters were identified among the LAB isolated: Lactobacillus plantarum, Lactobacillus fermentum, Leuconostoc pseudomesenteroides, and Enterococcus casseliflavus. Other taxa encompassed, for instance, Weissella. Only four clusters were found among the AAB identified: Acetobacter pasteurianus, Acetobacter syzygii-like bacteria, and two small clusters of Acetobacter tropicalis-like bacteria. Particular strains of L. plantarum, L. fermentum, and A. pasteurianus, originating from the environment, were well adapted to the environmental conditions prevailing during Ghanaian cocoa bean heap fermentation and apparently played a significant role in the cocoa bean fermentation process. Yeasts produced ethanol from sugars, and LAB produced lactic acid, acetic acid, ethanol, and mannitol from sugars and/or citrate. Whereas L. plantarum strains were abundant in the beginning of the fermentation, L. fermentum strains converted fructose into mannitol upon prolonged fermentation. A. pasteurianus grew on ethanol, mannitol, and lactate and converted ethanol into acetic acid. A newly proposed Weissella sp., referred to as "Weissella ghanaensis," was detected through PCR-DGGE analysis in some of the fermentations and was only occasionally picked up through culture-based isolation. Two new species of Acetobacter were found as well, namely, the species tentatively named "Acetobacter senegalensis" (A. tropicalis-like) and "Acetobacter ghanaensis" (A. syzygii-like).


Subject(s)
Acetobacter/isolation & purification , Biodiversity , Bioreactors , Cacao/metabolism , Gram-Positive Bacteria/isolation & purification , Lactobacillus/isolation & purification , Streptococcaceae/isolation & purification , Acetic Acid/metabolism , Acetobacter/classification , Acetobacter/metabolism , Cacao/microbiology , Carbohydrate Metabolism , Citric Acid/metabolism , Cluster Analysis , Colony Count, Microbial , DNA Fingerprinting , DNA, Bacterial/genetics , DNA, Ribosomal/genetics , Ethanol/metabolism , Fermentation , Fructose/metabolism , Gram-Positive Bacteria/classification , Gram-Positive Bacteria/metabolism , Lactic Acid/metabolism , Lactobacillus/classification , Lactobacillus/metabolism , Mannitol/metabolism , Streptococcaceae/classification , Streptococcaceae/metabolism , Yeasts/metabolism
16.
Int J Food Microbiol ; 112(2): 102-11, 2006 Nov 01.
Article in English | MEDLINE | ID: mdl-16950530

ABSTRACT

The effects of sugars relevant for sourdough fermentation (i.e. glucose, fructose, maltose, and sucrose) on the kinetics of the bacteriocin-producing Lactobacillus amylovorus DCE 471 strain were assessed. The sugars were applied solely or in combination in a sourdough simulation medium during batch fermentations at temperature and pH conditions encountered during the production of type II sourdoughs. When growing on a single energy source, glucose was preferentially consumed by L. amylovorus DCE 471, followed by maltose and fructose. The strain was unable to grow on sucrose. In glucose-containing mixtures, glucose was always consumed most rapidly by L. amylovorus DCE 471 and seemed to steer its growth during the early growth phase, mainly because of the delaying effect on maltose consumption. Maltose consumption started only when low glucose levels were reached. In all cases, fructose was used as an energy source and not as a terminal electron acceptor, since no acetic acid or mannitol were produced. Increased bacteriocin titres were observed with binary or ternary sugar combinations compared to single energy sources. Thus, the diversity of the energy source seemed to stimulate the production of amylovorin L. Cell growth of and production of amylovorin L by L. amylovorus DCE 471 paralleled for all sugar combinations tested.


Subject(s)
Bacteriocins/biosynthesis , Bread/microbiology , Carbohydrate Metabolism/physiology , Food Microbiology , Lactobacillus acidophilus/growth & development , Lactobacillus acidophilus/metabolism , Biomass , Colony Count, Microbial , Fermentation , Fructose/metabolism , Glucose/metabolism , Kinetics , Maltose/metabolism , Models, Biological , Sucrose/metabolism
17.
Int J Food Microbiol ; 107(2): 159-70, 2006 Mar 15.
Article in English | MEDLINE | ID: mdl-16290303

ABSTRACT

The biokinetics of cell growth and bacteriocin production of Enterococcus faecium FAIR-E 406 was studied as a function of temperature (20-45 degrees C) and pH (5.5-8.5) using de Man-Rogosa-Sharpe medium. Growth of E. faecium FAIR-E 406 was characterized by three successive growth phases and was modelled with the mechanistic nutrient depletion model. Bacteriocin production showed primary metabolite kinetics but was limited to the early growth phase. The critical biomass for switching off bacteriocin production was dependent on medium pH and incubation temperature, and was inversely correlated with the specific bacteriocin production. Doubling the concentration of the nitrogen source as well as a step-wise pH increase shifted the bacteriocin production towards a higher switch-off cell density.


Subject(s)
Bacteriocins/biosynthesis , Culture Media/chemistry , Enterococcus faecium/growth & development , Enterococcus faecium/metabolism , Food Microbiology , Biomass , Cell Count , Colony Count, Microbial , Fermentation , Hydrogen-Ion Concentration , Models, Biological , Temperature
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