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1.
J Microsc ; 266(2): 126-140, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28165142

RESUMO

Filamentous fungi have a complex morphology that induces fermentation process development issues, as a consequence of viscosity increase and diffusion limitations. In order to better understand the relationship between viscosity changes and fungus morphology during fermentations of Trichoderma reesei, an accurate image analysis method has been developed to provide quantitative and representative data for morphological analysis. This method consisted of a new algorithm called FACE that allowed sharp images to be created at all positions, segmentation of fungus, and morphological analysis using skeleton and topological approaches. It was applied and validated by characterizing samples of an industrial strain of Trichoderma reesei that had or had not been exposed to an extreme shear stress. This method allowed many morphological characteristics to be identified, among which nine relevant criteria were extracted, regarding the impact of shear stress on the fungus and on the viscosity of the fermentation medium.


Assuntos
Fungos/citologia , Processamento de Imagem Assistida por Computador/métodos , Microscopia/métodos , Trichoderma/citologia , Fermentação , Fungos/metabolismo , Microbiologia Industrial/métodos , Trichoderma/metabolismo
2.
J Appl Microbiol ; 117(1): 196-207, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24661271

RESUMO

AIMS: To help cells to better resist the stressful conditions associated with the freeze-drying process during starter production, we investigated the effect of various osmotic conditions on growth, survival and acidification activity of Lactobacillus buchneri R1102, after freeze-drying and during storage for 3 months at 25°C. METHODS AND RESULTS: High survival rates during freeze-drying, but not during storage, were obtained when 0·1 mol l(-1) KCl was added at the beginning of fermentation, without any change in membrane properties and betaine accumulation. This condition made it possible to maintain a high acidification rate throughout the process. In contrast, the addition of 0·6 mol l(-1) KCl concentrations at the beginning of fermentation led to a high survival rate during storage that was related to high intracellular betaine levels, low membrane fluidity and high cycC19:0 concentrations. However, these modifications induced the degradation of acidification activity during storage. When a moderate stress was applied by combining 0·1 mol l(-1) KCl at the beginning and 0·6 mol l(-1) KCl at the end of fermentation, betaine accumulated in the cells without any membrane alteration, allowing them to maintain high acidification activity and survival rate during storage. CONCLUSION: Specific osmotic conditions during fermentation induced intracellular betaine accumulation and modifications of membrane character-istics, thus affecting stress resistance of Lact. buchneri R1102. A slight osmotic stress made it possible to maintain a high acidification activity, whereas a high osmotic stress at the end of fermentation led to the preservation of cell survival during freeze-dried storage. SIGNIFICANCE AND IMPACT OF THE STUDY: This study revealed that the survival and preservation of acidification activity of freeze-dried Lact. buchneri R1102 during starter production can be improved by using appropriate osmotic conditions.


Assuntos
Betaína/metabolismo , Lactobacillus/efeitos dos fármacos , Fluidez de Membrana/efeitos dos fármacos , Cloreto de Potássio/farmacologia , Preservação Biológica/métodos , Fermentação , Liofilização , Concentração de Íons de Hidrogênio , Lactobacillus/fisiologia , Viabilidade Microbiana/efeitos dos fármacos , Pressão Osmótica
3.
Food Res Int ; 168: 112762, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37120212

RESUMO

Ambriss, Serdaleh and Labneh El Darff are traditional Lebanese products made from fermented goat's milk. A questionnaire completed by 50 producers of these products showed that they are prepared by periodic percolation either by milk or by Laban in amphora or goat skins during the lactation season. Production is carried out on a small scale and in a limited number of production units, often by elderly people, resulting in a real risk of disappearance of these products and loss of the corresponding microbial resources. In this study, 34 samples from 18 producers were characterized by culture-dependent and -independent analyses. The results obtained from these two methods were radically different, the latter revealing in Ambriss and Serdaleh the co-dominance of Lactobacillus kefiranofaciens, a fastidious-growing species, and Lactococcus lactis in a viable but not culturable state. Overall, their composition is reminiscent of kefir grains. Phylogenomic and functional analyses of the genomes of the key species Lb. kefiranofaciens have revealed differences from those found in kefir, particularly in their polysaccharide genes, which may explain the absence of grains. However, Labneh El Darff displayed a dominance of Lactobacillus delbrueckii, probably due to the addition of Laban. In addition, the study identified several zoonotic pathogens, including Streptococcus parasuis, which dominated in one sample. Metagenome-Assembled Genome (MAG) analysis indicated that this pathogen acquired lactose utilization genes through horizontal gene transfer. The contamination of the herd with Mycoplasmopsis agalactiae in the Chouf region was also revealed by MAG analysis of the Serdaleh samples. Antibiotic resistance genes were detected in most of the samples, particularly in the Serdaleh ones, where the dominant L. lactis strains possessed a plasmid with a multi-resistance island. Finally, this study paves the way for further analyses to shed light on the resilience of these ecosystems established in amphora or in goatskins and to improve hygiene practices for milk production.


Assuntos
Produtos Fermentados do Leite , Kefir , Lactococcus lactis , Feminino , Animais , Ecossistema , Cabras
4.
Arch Microbiol ; 193(12): 905-10, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21892611

RESUMO

To better understand the phenomena governing the establishment of the oral bacterium Streptococcus salivarius in the mouth, the effect of some environmental factors has been studied in complemented artificial saliva, under oral pH and temperature conditions. Three salivary enzymes at physiological concentrations were tested: peroxidase, lysozyme and amylase, as well as injection of exhaled air. Injection of air containing 5% CO2 and 16% O2 induced a deleterious effect on S. salivarius K12, mainly by increasing redox potential. Addition of lysozyme slightly affected the physiological state of S. salivarius by altering membrane integrity. In contrast, peroxidase was not detrimental as it made it possible to decrease the redox potential. The addition of amylase reduced the specific growth rate of S. salivarius by formation of a complex with amylase and mucins, but led to high final biomass, as a result of enzymatic degradation of some nutrients. Finally, this work demonstrated that salivary enzymes had a slight impact on S. salivarius behaviour. It can thus be concluded that this bacterium was well adapted to in-mouth conditions, as it was able to resist certain salivary enzymes, even if tolerance to expired air was affected, as a result of an increased redox potential.


Assuntos
Ar/análise , Saliva Artificial/metabolismo , Saliva/enzimologia , Streptococcus/crescimento & desenvolvimento , Amilases/metabolismo , Membrana Celular/fisiologia , Viabilidade Microbiana , Boca/enzimologia , Boca/microbiologia , Muramidase/metabolismo , Oxirredução , Peroxidase/metabolismo , Saliva/microbiologia , Streptococcus/fisiologia
5.
J Appl Microbiol ; 111(3): 631-41, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21672100

RESUMO

AIMS: To help gain a better understanding of factors influencing the establishment within the oral cavity of Streptococcus salivarius K12, a commensal oral bacterium, we characterized its behaviour in artificial saliva. METHODS AND RESULTS: Streptococcus salivarius K12 was grown in artificial saliva complemented with a representative meal, under oral pH and temperature conditions. Exponential growth phase was characterized by a high specific growth rate (2.8 h(-1)). During maintenance phase, an uncoupling between growth and lactic acid production occurred, which allowed maintaining viability (95%), intracellular pH (6.6) and membrane polarisation (95%), and thus proton motive force. However, in late stationary phase, viability (64%) and vitality were degraded as a result of lower synthesis of energetic and glycogen-related proteins as compared to a richer medium. CONCLUSIONS: Streptococcus salivarius was able to rapidly grow in complemented artificial saliva. Nevertheless, a degradation of its physiological state was observed in late-stationary phase. SIGNIFICANCE AND IMPACT OF THE STUDY: This work demonstrates, for the first time, that artificial saliva was a convenient medium that permitted Strep. salivarius to grow in oral conditions (physico-chemical environment, addition of meals) but not to maintain cellular viability and vitality in starvation conditions.


Assuntos
Boca/microbiologia , Saliva Artificial/química , Streptococcus/crescimento & desenvolvimento , Meios de Cultura/química , Fermentação , Citometria de Fluxo , Glucose/análise , Concentração de Íons de Hidrogênio , Ácido Láctico/análise , Ácido Láctico/biossíntese , Lactose/análise , Viabilidade Microbiana , Proteoma/análise , Streptococcus/metabolismo , Temperatura
6.
Biotechnol Bioeng ; 106(4): 573-83, 2010 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-20178118

RESUMO

This study is an evaluation of liquid state NMR as a tool for analyzing the lipid composition of algal cultures used for biodiesel production. To demonstrate the viability of this approach, (13)C NMR was used to analyze the lipid composition of intact cells of the algal species, Neochloris oleoabundans (UTEX #1185). Two cultures were used in this study. One culture was "healthy" and grown in conventional media, whereas the other culture was "nitrogen-starved" and grown in media that lacked nitrate. Triglyceride was determined to be present in both cultures by comparing the algal NMR spectra with published chemical shifts for a wide range of lipids and with a spectrum obtained from a triglyceride standard (glyceryl trioleate). In addition, it is shown that (1) the signal-to-noise ratio of the approximately 29.5 ppm methylene peak is indicative of the lipid content and (2) the nitrogen-starved culture contained a greater lipid content than the healthy culture, as expected. Furthermore, the nitrogen-starved culture produced spectra that primarily contained the characteristic peaks of triglyceride (at approximately 61.8 and approximately 68.9 ppm), whereas the healthy culture produced spectra that contained several additional peaks in the glycerol region, likely resulting from the presence of monoglyceride and diglyceride. Finally, potential interferences are evaluated (including the analysis of phospholipids via (31)P NMR) to assess the specificity of the acquired spectra to triglyceride. These results indicate that NMR is a useful diagnostic tool for selectively identifying lipids in algae, with particular relevance to biodiesel production.


Assuntos
Clorófitas/química , Lipídeos/análise , Espectroscopia de Ressonância Magnética/métodos , Isótopos de Carbono/metabolismo , Clorófitas/crescimento & desenvolvimento , Meios de Cultura/química , Coloração e Rotulagem
7.
Biotechnol Bioeng ; 105(5): 889-98, 2010 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-19998275

RESUMO

Preliminary feasibility studies were performed using Stokes Raman scattering for compositional analysis of algae. Two algal species, Chlorella sorokiniana (UTEX #1230) and Neochloris oleoabundans (UTEX #1185), were chosen for this study. Both species were considered to be candidates for biofuel production. Raman signals due to storage lipids (specifically triglycerides) were clearly identified in the nitrogen-starved C. sorokiniana and N. oleoabundans, but not in their healthy counterparts. On the other hand, signals resulting from the carotenoids were found to be present in all of the samples. Composition mapping was conducted in which Raman spectra were acquired from a dense sequence of locations over a small region of interest. The spectra obtained for the mapping images were filtered for the wavelengths of characteristic peaks that correspond to components of interest (i.e., triglyceride or carotenoid). The locations of the components of interest could be identified by the high intensity areas in the composition maps. Finally, the time evolution of fluorescence background was observed while acquiring Raman signals from the algae. The time dependence of fluorescence background is characterized by a general power law decay interrupted by sudden high intensity fluorescence events. The decreasing trend is likely a result of photo-bleaching of cell pigments due to prolonged intense laser exposure, while the sudden high intensity fluorescence events are not understood.


Assuntos
Eucariotos/química , Análise Espectral Raman/métodos , Chlorella/química , Clorófitas/química , Fluorescência
8.
Rev Med Interne ; 40(11): 754-757, 2019 Nov.
Artigo em Francês | MEDLINE | ID: mdl-31431320

RESUMO

INTRODUCTION: Cervical cancer is the twelfth most frequent cancer in women in France. Glassy cell carcinoma is a rare histological entity, rapidly aggressive, associated with a poor prognosis. CASE REPORT: A 30-year-old woman was admitted in an internal medicine department for polyarthralgia with high grade fever, evolving for 3 weeks. There was an inflammatory syndrome. The 18-FDG-PET-scan showed inflammatory lymph nodes as well as disseminated osteolytic lesions, and a primitive pelvic tumor. A 3cm tumor of the cervix was found during the gynaecologic examination. Histological analysis elicited a high-index mitotic carcinoma, glassy cell carcinoma type. Despite chemotherapy, the outcome was poor, with early death occurring after three months of follow-up. CONCLUSION: The glassy cell carcinoma of the cervix should be considered as an aetiology of bone metastases in young female patients.


Assuntos
Carcinoma Adenoescamoso/patologia , Neoplasias do Colo do Útero/patologia , Adulto , Neoplasias Ósseas/diagnóstico por imagem , Neoplasias Ósseas/secundário , Evolução Fatal , Feminino , Humanos , Metástase Linfática , Imageamento por Ressonância Magnética
9.
J Neonatal Perinatal Med ; 12(4): 457-464, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31282431

RESUMO

BACKGROUND: The objective of the study was to assess perinatal grief experienced after continuing pregnancy and comfort care in women diagnosed with lethal fetal condition compared with termination of pregnancy for fetal anomaly (TOPFA). METHODS: This was a retrospective observational study which included women who chose to continue their pregnancy after the diagnosis of lethal fetal condition with comfort care support at birth at the Prenatal Diagnosis Center of Rennes Hospital from January 2007 to January 2017. Women were matched with controls who underwent TOPFA for the same type of fetal anomaly, gestational age at diagnosis and year. Women were evaluated by a questionnaire including the Perinatal Grief Scale. RESULTS: There were 28 patients in the continuing pregnancy group matched with 56 patients in the TOPFA group. Interval between fetal loss and completion of questionnaire was 6±3 years. Perinatal grief score was similar at 61±22 vs 58±18 (p = 0.729) in the continuing pregnancy and TOPFA groups, respectively. Women in the TOPFA group expressed more guilt. The cesarean-section rate in the continuing pregnancy group was 25%. CONCLUSION: Perinatal grief experienced by women opting for continuing pregnancy and comfort care after diagnosis of a potentially lethal fetal anomaly is not more severe than for those choosing TOPFA.


Assuntos
Aborto Induzido/estatística & dados numéricos , Comportamento de Escolha , Doenças Fetais/diagnóstico , Pesar , Cuidados Paliativos/métodos , Diagnóstico Pré-Natal/psicologia , Aborto Induzido/psicologia , Adulto , Feminino , Doenças Fetais/psicologia , Idade Gestacional , Humanos , Recém-Nascido , Conforto do Paciente , Gravidez , Escalas de Graduação Psiquiátrica , Estudos Retrospectivos
10.
J Appl Microbiol ; 105(4): 1071-80, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18498349

RESUMO

AIMS: This work aimed at clarifying the physiological responses of Lactobacillus delbrueckii subsp. bulgaricus CFL1 cells after exposure to acidification at the end of fermentation, in relation to their cryotolerance. METHODS AND RESULTS: Cells acidified at the end of the fermentation (pH 5.25 for 30 min) had their cryotolerance improved as compared to the reference condition (pH 6.0). By analyzing the cytosolic proteome, it was established that changes occurred in the synthesis of 21 proteins, involved in energy metabolism, nucleotide and protein synthesis and stress response. Acidification also induced a slight decrease in unsaturated to saturated and cyclic to saturated membrane fatty acid ratios. CONCLUSIONS: Lactobacillus bulgaricus CFL1 was able to develop a combined physiological response at both membrane and cytosolic levels. This acid adaptation was referred as a cross-protection phenomenon as it allowed the cells to become more tolerant to cold stress. SIGNIFICANCE AND IMPACT OF THE STUDY: This study increased knowledge concerning the physiological mechanisms that explained the cross-protection by acid adaptation. It may be useful for improving cryotolerance of lactic acid bacteria, either in cells banks or in an industrial context.


Assuntos
Adaptação Fisiológica , Microbiologia de Alimentos , Congelamento , Lactobacillus delbrueckii/fisiologia , Probióticos , Iogurte , Membrana Celular/metabolismo , Citoplasma/metabolismo , Ácidos Graxos/análise , Fermentação , Concentração de Íons de Hidrogênio , Lactobacillus delbrueckii/metabolismo , Viabilidade Microbiana , Proteômica
11.
Water Res ; 40(12): 2327-38, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16764900

RESUMO

Soil absorption systems (SAS) are used commonly to treat and disperse septic tank effluent (STE). SAS can hydraulically fail as a result of the low permeable biomat zone that develops on the infiltrative surface. The objectives of this experiment were to compare the hydraulic properties of biomats grown in soils of different textures, to investigate the long-term acceptance rates (LTAR) from prolonged application of STE, and to assess if soils were of major importance in determining LTAR. The STE was applied to repacked sand, Oxisol and Vertisol soil columns over a period of 16 months, at equivalent hydraulic loading rates of 50, 35 and 8L/m(2)/d, respectively. Infiltration rates, soil matric potentials, and biomat hydraulic properties were measured either directly from the soil columns or calculated using established soil physics theory. Biomats 1 to 2 cm thick developed in all soils columns with hydraulic resistances of 27 to 39 d. These biomats reduced a 4 order of magnitude variation in saturated hydraulic conductivity (K(s)) between the soils to a one order of magnitude variation in LTAR. A relationship between biomat resistance and organic loading rate was observed in all soils. Saturated hydraulic conductivity influenced the rate and extent of biomat development. However, once the biomat was established, the LTAR was governed by the resistance of the biomat and the sub-biomat soil unsaturated flow regime induced by the biomat. Results show that whilst initial soil K(s) is likely to be important in the establishment of the biomat zone in a trench, LTAR is determined by the biomat resistance and the unsaturated soil hydraulic conductivity, not the K(s) of a soil. The results call into question the commonly used approach of basing the LTAR, and ultimately trench length in SAS, on the initial K(s) of soils.


Assuntos
Resíduos Industriais , Esgotos , Solo , Eliminação de Resíduos Líquidos/métodos , Movimentos da Água , Purificação da Água/métodos , Filtração
12.
Sci Total Environ ; 569-570: 815-829, 2016 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-27392335

RESUMO

Landfills can be regarded as a particular type of contaminated land that has a potential to directly and indirectly pollute all of the four main spheres of the environment which are the lithosphere, atmosphere, hydrosphere and eventually adversely impact the biosphere. Therefore, environmental risk assessment of a landfill has to be more integrated and holistic by virtue of its nature of being a multidimensional pollutant source. Despite this, although various risk assessment approaches have been adopted for landfill waste disposal sites, there are still wide-ranging knowledge gaps and limitations which need to be addressed. One important knowledge gap and limitation of current risk assessment approaches is the inability to fully identify, categorise and aggregate all individual risks from all combinations of hazards, pathways and targets/receptors (e.g. water, air, soil and biota) in connection to a certain landfill leachate and yet at any stage of the landfill cycle. So such an approach is required that could not only integrate all possible characteristics of varying scenarios but also contain the ability to establish an overall risk picture, irrespective of the lifecycle stage of the landfill (e.g. planning stage/pre-operation, in-operation or post-operation/closed). One such approach to address the wide-breadth of landfill impact risks is by developing a more holistic risk assessment methodology, whose conceptual framework is presented in this paper for landfill leachate in a whole-system format. This conceptual framework does not only draw together various constituting factors and sub-factors of risk assessment in a logical sequence and categorical order, but also indicates the "what, why, when and how" outputs of and inputs to these factors and sub-factors can be useful. The framework is designed to identify and quantify a range of risks associated with all stages of the landfill lifecycle, and yet in a more streamlined, logical, categorical and integrated format, offering a more standardised and unified whole-system approach.


Assuntos
Monitoramento Ambiental/métodos , Medição de Risco/métodos , Instalações de Eliminação de Resíduos , Poluentes Químicos da Água/análise , Modelos Teóricos
13.
J Biotechnol ; 34(1): 87-95, 1994 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-7764746

RESUMO

The influence of dilution rate and cell immobilization on plasmid stability in recombinant strains of Lactococcus lactis subsp. lactis was investigated during continuous cultures. The studied strains, L. lactis IL2682 and IL2683, contained plasmids pIL9 (Lac+), pIL205 (CmR) and plasmids pIL252 (low copy number) and pIL253 (high copy number), respectively, that conferred resistance to erythromycin. Plasmid pIL205 was remarkably stable. Dilution rate did not affect the rate of loss of plasmids pIL252 and pIL253 significantly. Nevertheless, the loss of plasmid pIL253 was apparent after a further 21 generations when the dilution rate was decreased from 0.70 h-1 to 0.55 h-1. Cell immobilization in beads of kappa-carrageenan/locust bean gum improved plasmid stability by factors of 4.5 for pIL253 and 6.5 for pIL252. Thus, 10% of cells containing plasmids pIL252 or pIL253 were still present after 370 or 540 generations, respectively, compared with 50 or 210 generations in free cell cultures.


Assuntos
Lactococcus lactis/genética , Plasmídeos , Meios de Cultura , DNA Recombinante , Lactococcus lactis/crescimento & desenvolvimento
14.
Int J Food Microbiol ; 51(1): 53-65, 1999 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-10563463

RESUMO

Mixed cultures of Lactobacillus curvatus and Enterobacter cloacae were chosen as a model system to quantitatively study microbial interactions involved in food spoilage and food preservation. In this paper models were developed to predict the individual behaviour of L. curvatus and E. cloacae in pure suspension cultures as a function of the glucose and lactate concentration and the pH. In a second paper these models will be used to predict the moment of interaction in mixed suspension cultures and the cell concentrations at this moment. The effect of pH on the maximum specific growth rate could be described by a parabolic equation for L. curvatus and E. cloacae. E. cloacae is clearly more sensitive to a pH decrease than L. curvatus, as may be concluded from the theoretical minimum pH for growth of 5.6 for E. cloacae and 4.3 for L. curvatus. For both organisms no effect of glucose on the maximum specific growth rate could be detected and Monod kinetics with a low Monod constant was assumed. For L. curvatus the effect of lactate on the maximum specific growth rate at different initial pH values could be described by a linear relationship. For E. cloacae a slight effect of lactate on the maximum specific growth rate could only be detected at pH 7. However, this effect was negligible compared to the effect of the pH. For both organisms the lag time was modelled by the inverse of the specific growth rate. It can be concluded that, with regard to interactions between L. curvatus and E. cloacae, the pH is likely to be the most important factor in the case where L. curvatus is the dominant organism. Substrate limitation is likely to become important in the case where E. cloacae is the dominant organism or for media with a high buffer capacity.


Assuntos
Enterobacter cloacae/crescimento & desenvolvimento , Microbiologia de Alimentos , Conservação de Alimentos , Lactobacillus/crescimento & desenvolvimento , Modelos Biológicos , Animais , Cromatografia Líquida de Alta Pressão , Contagem de Colônia Microbiana , Infecções por Enterobacteriaceae/prevenção & controle , Glucose/análise , Glucose/metabolismo , Concentração de Íons de Hidrogênio , Cinética , Ácido Láctico/análise , Ácido Láctico/metabolismo , Carne/microbiologia , Análise de Regressão , Suínos
15.
Int J Food Microbiol ; 51(1): 67-79, 1999 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-10563464

RESUMO

The modelling approach presented in this study can be used to predict when interactions between microorganisms in homogenous systems occur. It was tested for the interaction between Lactobacillus curvatus and Enterobacter cloacae. In this binary system, L. curvatus produces lactic acid which decreases the pH in the system. The pH decrease was found to be the main limiting factor of growth of both E. cloacae and L. curvatus. This resulted in E. cloacae reaching its final concentration earlier when compared to its growth in pure culture. The models consisted of a set of first order ordinary differential equations describing the growth, consumption and production rates of both microorganisms. The parameters for these equations were obtained from pure culture studies and from literature. These equations were solved using a combination of analytical and numerical methods. The prediction of growth in mixed culture using parameters from pure culture experiments and literature were close to the experimental data. Both model predictions and experimental validation indicated that interaction occurs when the concentration of L. curvatus reaches 10(8) cfu/ml. At that moment in time, the pH had decreased to inhibiting levels. These concentrations of microorganisms (10(8) cfu/ml) do occur in fermented products where interactions obviously are important. In nonfermented foods however, this level of microorganisms indicate that spoilage has occurred or is about to start. Microbial interactions can therefore be neglected when predicting shelf life or safety of food products in most cases.


Assuntos
Enterobacter cloacae/crescimento & desenvolvimento , Microbiologia de Alimentos , Conservação de Alimentos , Lactobacillus/crescimento & desenvolvimento , Modelos Biológicos , Contagem de Colônia Microbiana , Infecções por Enterobacteriaceae/prevenção & controle , Previsões , Glucose/metabolismo , Concentração de Íons de Hidrogênio , Cinética , Ácido Láctico/biossíntese , Análise Numérica Assistida por Computador , Análise de Regressão
16.
Immunohematology ; 11(3): 74-7, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-15447062

RESUMO

A screening program was implemented to identify hrB- donors. D- C+, D-C-, and D+C- samples from African-American donors were typed with multiple examples of anti-hrB and anti-hrB-like, and one example each of anti-V and anti-VS. Of 75 D-C+ donors, 4 (5%) typed as hrB-, and 14 others had weak or variable expression of hrB. Of these 18 individuals, 15 were V-VS+, and 3 were V+VS+. No hrB- sample was found in 90 C- donors, 26 of whom were V+VS+, and 1 was V-VS+. A review of our records of 44 hrB- patients and donors studied earlier revealed that at least 12, and possibly as many as 30, carried r or rs. All hrB- donors found in our screening program had D-C+VS+ RBCs, indicating an overrepresentation of r. Our record review also showed that the presence of r and rs more often results in hrB- RBCs, and that the most effective way to screen for hrB- donors is to type African Americans who have D-C+ RBCs.

17.
Equine Vet J ; 16(4): 371-3, 1984 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-6479137

RESUMO

Five foals from two to three days old were given a single oral dose of ampicillin trihydrate (20 mg/kg bodyweight [bwt]). Serum ampicillin concentrations were measured serially over a 24 h period. The study was repeated in the same foals at 16 to 21 days old. The mean peak serum ampicillin concentration at two to three days old was 5.0 micrograms/ml at 1 h after treatment; the mean peak serum concentration at 16 to 21 days old was 2.7 micrograms/ml at 2 h. The concentrations steadily declined and ampicillin was not detected in the serum from any of the foals by 24 h. Serum clearance averaged 17.7 ml/min/kg at two to three days and 35.8 ml/min/kg at 16 to 21 days.


Assuntos
Ampicilina/metabolismo , Animais Recém-Nascidos/sangue , Cavalos/sangue , Ampicilina/sangue , Animais , Feminino , Cinética , Masculino
18.
Am J Vet Res ; 47(2): 453-4, 1986 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-3954234

RESUMO

Six healthy pony foals, from 2 to 11 days of age, were given a single IM injection of amikacin sulfate (250 mg/ml) at a dosage rate of 7 mg/kg of body weight. Serum amikacin concentrations were measured serially over a 24-hour period. The mean peak serum concentration was 14.7 micrograms/ml at 0.5 hour. The elimination rate constant for amikacin was 0.24/hour, the elimination half-life was 3.0 hours, and the apparent volume of distribution was 0.58 L/kg.


Assuntos
Amicacina/sangue , Cavalos/sangue , Canamicina/análogos & derivados , Amicacina/administração & dosagem , Animais , Animais Recém-Nascidos , Meia-Vida , Injeções Intramusculares , Cinética , Taxa de Depuração Metabólica
19.
Am J Vet Res ; 45(8): 1610-3, 1984 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-6476574

RESUMO

Six mares were given 5 IM injections (at 12-hour intervals between doses) of amikacin sulfate at a dosage of 7 mg/kg of body weight. Serum amikacin concentrations were measured serially throughout the study; synovial, peritoneal, endometrial, and urine concentrations were determined after the last injection. Amikacin concentrations of the CSF were measured serially in 3 of the 6 mares; 1 of the 3 mares had septic meningitis. Mean serum amikacin concentrations peaked at 1 to 2 hours after IM injection. The highest mean serum concentration was 19.2 micrograms/ml (1.5 hours after the 5th injection). The highest mean synovial concentration was 10.8 micrograms/ml at 2 hours after the 5th injection; the highest mean peritoneal concentration was 16.2 micrograms/ml at 3 hours after the 5th injection. The mean endometrial amikacin concentration was 2.5 micrograms/g (1.5 hours after the 5th injection). Amikacin reached a CSF concentration of 0.97 micrograms/ml in the mare with meningitis, but amikacin was not detected in CSF of healthy mares. Urine concentrations reached 1,458 micrograms/ml. Pharmacokinetic values were estimated after the 1st injection (elimination rate constant = 0.31/hour; half-life = 2.3 hours; apparent volume of distribution = 0.26 L/kg), and after the 5th injection (elimination rate constant = 0.28/hour; half-life = 2.6 hours; apparent volume of distribution = 0.30 L/kg); significant differences were not observed.


Assuntos
Amicacina/metabolismo , Líquidos Corporais/metabolismo , Endométrio/metabolismo , Cavalos/metabolismo , Canamicina/análogos & derivados , Amicacina/administração & dosagem , Animais , Líquido Ascítico/metabolismo , Feminino , Doenças dos Cavalos/metabolismo , Injeções Intramusculares/veterinária , Meningite/metabolismo , Meningite/veterinária , Infecções por Pseudomonas/metabolismo , Infecções por Pseudomonas/veterinária , Líquido Sinovial/metabolismo
20.
Ann Otolaryngol Chir Cervicofac ; 111(7): 363-70, 1994.
Artigo em Francês | MEDLINE | ID: mdl-7645884

RESUMO

UNLABELLED: Currently, the importance of autoimmune phenomenon in the genesis of inner ear disease is difficult to evaluate because the clinical and biological criteria of autoimmune deafness has not yet been well defined. Among patients with sensorineural hearing loss, is it possible to define a group presenting clinical and biological findings suggesting autoimmune disease? What are the most sensitive and selective biological tests for autoimmune disease of the inner ear? Do patients with autoimmune deafness present a particular clinical, genetic and for biological profile? In order to answer these questions, we retrospectively studied 35 patients followed in our service from June 1990 to August, 1992 for sensorineural hearing loss of an unknown origin. All patients had had a complete biological work-up including examinations which would detect inflammation (erythrocyte sedimentation rate immunoglobulin IgG, IgA, IgM assays, protein electrophonesis) or dysimmunity (circulating immune complexes, marked depression of serum complement levels the presence of antinuclear antiorgan antibodies, or anticardiolipid and type II anticollagen antibodies). HLA typing had also been done. RESULTS. Only 4 patients had a biological profile suggesting dysimmunity. These patients presented no common clinical or genetic characteristic which would distinguish them as a separate subgroup. Biologically, anticardiolipid antibodies were found in all 4 of these patients and only in these patients. These 4 patients also had circulating immune complexes and 3 of the 4 patients also had elevated levels of IgA and IgM. IN CONCLUSION: including assays for antiphospholipid antibodies in the work-up of sensorineural hearing loss could reveal an antiphospholipid syndrome affecting the inner ear. Theoretically, the use of anticoagulants and agents decreasing platelet aggregation could provide effective treatment.


Assuntos
Síndrome Antifosfolipídica/complicações , Autoanticorpos/análise , Perda Auditiva Neurossensorial/etiologia , Adulto , Anticorpos Antifosfolipídeos/análise , Feminino , Antígenos HLA/análise , Perda Auditiva Neurossensorial/tratamento farmacológico , Humanos , Masculino , Inibidores da Agregação Plaquetária/uso terapêutico , Estudos Retrospectivos
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