Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 35
Filter
1.
Animal ; 15(5): 100197, 2021 May.
Article in English | MEDLINE | ID: mdl-34029797

ABSTRACT

Betaine is an osmolyte with the potential to increase volatile fatty acids (VFAs) production and hence improve intestinal health.The present study investigated how betaine affects portal and arterial concentrations and net portal absorption (NPA) of VFA in growing Iberian pigs. Eight 30 kg BW Iberian growing barrows with indwelling catheters in portal vein, ileal vein and carotid artery were randomly assigned to a control diet or a diet supplemented with 0.5% betaine. Para-aminohippuric acid was infused into the ileal vein as a marker to determine portal blood flow using the dilution method. Blood samples were simultaneously taken from the carotid artery and portal vein at -60, 60, 120, 180, 240, 300 and 360 min after feeding 1 200 g of the diet. The NPA of VFA (acetate, propionate, butyrate, valerate, isobutyrate and caproate) was determined by multiplying the porto-arterial plasma concentration differences by portal plasma flow. Betaine increased NPA of acetate (1.44 fold; P < 0.001) and total VFA (0.55 fold; P < 0.001) while decreased NPA of propionate (-0.38 fold; P < 0.05) and valerate (-1.46 fold; P < 0.05) compared with control pigs. Estimated heat production potentially derived from NPA of VFA accounted for 0.20-0.27 of metabolizable energy for maintenance. Acetate and propionate accounted for most of the total VFA estimated heat production (0.83-0.89). Regarding bacterial communities, betaine apparently did not change the DNA abundance of fecal total bacteria, Lactobacillus, Bifidobacterium, Enterobacteriaceae, Bacteroides and the Clostridium clusters I, IV and XIV. In conclusion, betaine increased portal appearance and NPA of VFA, contributing to cover maintenance energy requirements.


Subject(s)
Betaine , Fatty Acids, Volatile , Animals , Butyrates , Diet , Propionates , Swine
2.
Rev Sci Instrum ; 91(4): 045003, 2020 Apr 01.
Article in English | MEDLINE | ID: mdl-32357757

ABSTRACT

The Laser Interferometer Space Antenna Pathfinder (LPF) main observable, labeled Δg, is the differential force per unit mass acting on the two test masses under free fall conditions after the contribution of all non-gravitational forces has been compensated. At low frequencies, the differential force is compensated by an applied electrostatic actuation force, which then must be subtracted from the measured acceleration to obtain Δg. Any inaccuracy in the actuation force contaminates the residual acceleration. This study investigates the accuracy of the electrostatic actuation system and its impact on the LPF main observable. It is shown that the inaccuracy is mainly caused by the rounding errors in the waveform processing and also by the random error caused by the analog to digital converter random noise in the control loop. Both errors are one order of magnitude smaller than the resolution of the commanded voltages. We developed a simulator based on the LPF design to compute the close-to-reality actuation voltages and, consequently, the resulting actuation forces. The simulator is applied during post-processing the LPF data.

3.
Phys Rev Lett ; 123(11): 111101, 2019 Sep 13.
Article in English | MEDLINE | ID: mdl-31573236

ABSTRACT

We report on the results of the LISA Pathfinder (LPF) free-fall mode experiment, in which the control force needed to compensate the quasistatic differential force acting on two test masses is applied intermittently as a series of "impulse" forces lasting a few seconds and separated by roughly 350 s periods of true free fall. This represents an alternative to the normal LPF mode of operation in which this balancing force is applied continuously, with the advantage that the acceleration noise during free fall is measured in the absence of the actuation force, thus eliminating associated noise and force calibration errors. The differential acceleration noise measurement presented here with the free-fall mode agrees with noise measured with the continuous actuation scheme, representing an important and independent confirmation of the LPF result. An additional measurement with larger actuation forces also shows that the technique can be used to eliminate actuation noise when this is a dominant factor.

4.
Phys Rev Lett ; 120(6): 061101, 2018 Feb 09.
Article in English | MEDLINE | ID: mdl-29481269

ABSTRACT

In the months since the publication of the first results, the noise performance of LISA Pathfinder has improved because of reduced Brownian noise due to the continued decrease in pressure around the test masses, from a better correction of noninertial effects, and from a better calibration of the electrostatic force actuation. In addition, the availability of numerous long noise measurement runs, during which no perturbation is purposely applied to the test masses, has allowed the measurement of noise with good statistics down to 20 µHz. The Letter presents the measured differential acceleration noise figure, which is at (1.74±0.05) fm s^{-2}/sqrt[Hz] above 2 mHz and (6±1)×10 fm s^{-2}/sqrt[Hz] at 20 µHz, and discusses the physical sources for the measured noise. This performance provides an experimental benchmark demonstrating the ability to realize the low-frequency science potential of the LISA mission, recently selected by the European Space Agency.

5.
Animal ; 11(11): 1939-1948, 2017 Nov.
Article in English | MEDLINE | ID: mdl-28462771

ABSTRACT

Rusitec fermenters are in vitro systems widely used to study ruminal fermentation, but little is known about the microbial populations establishing in them. This study was designed to assess the time evolution of microbial populations in fermenters fed medium- (MC; 50% alfalfa hay : concentrate) and high-concentrate diets (HC; 15 : 85 barley straw : concentrate). Samples from solid (SOL) and liquid (LIQ) content of fermenters were taken immediately before feeding on days 3, 8 and 14 of incubation for quantitative polymerase chain reaction and automated ribosomal intergenic spacer analysis analyses. In SOL, total bacterial DNA concentration and relative abundance of Ruminococcus flavefaciens remained unchanged over the incubation period, but protozoal DNA concentration and abundance of Fibrobacter succinogenes, Ruminococcus albus and fungi decreased and abundance of methanogenic archaea increased. In LIQ, total bacterial DNA concentration increased with time, whereas concentration of protozoal DNA and abundance of methanogens and fungi decreased. Diet×time interactions were observed for bacterial and protozoal DNA and relative abundance of F. succinogenes and R. albus in SOL, as well as for protozoal DNA in LIQ. Bacterial diversity in SOL increased with time, but no changes were observed in LIQ. The incubated diet influenced all microbial populations, with the exception of total bacteria and fungi abundance in LIQ. Bacterial diversity was higher in MC-fed than in HC-fed fermenters in SOL, but no differences were detected in LIQ. Values of pH, daily production of volatile fatty acids and CH4 and isobutyrate proportions remained stable over the incubation period, but other fermentation parameters varied with time. The relationships among microbial populations and fermentation parameters were in well agreement with those previously reported in in vivo studies. Using 15N as a microbial marker or quantifying total microbial DNA for estimating microbial protein synthesis offered similar results for diets comparison, but both methods presented contrasting results for microbial growth in SOL and LIQ phases. The study showed that fermentation parameters remained fairly stable over the commonly used sampling period (days 8 to 14), but shifts in microbial populations were detected. Moreover, microbial populations differed markedly from those in the inocula, which indicates the difficulty of directly transposing results on microbial populations developed in Rusitec fermenters to in vivo conditions.


Subject(s)
Animal Feed/analysis , Bacteria/growth & development , Fermentation , Sheep/microbiology , Animals , Bacteria/classification , Cross-Over Studies , DNA, Bacterial/analysis , Diet/veterinary , Hordeum , Medicago sativa , Rumen/microbiology , Rumen/physiology , Sheep/physiology
6.
Comput Biol Med ; 75: 173-80, 2016 08 01.
Article in English | MEDLINE | ID: mdl-27294779

ABSTRACT

BACKGROUND AND OBJECTIVE: Propofol is widely used for hypnosis induction and maintenance of general anesthesia. Its effect can be assessed using the bispectral index (BIS). Many automatic infusion systems are based in pharmacokinetics (PK) and pharmacodynamics (PD) models to predict the response of the patient to the drug. However, all these models do not take into account intra and inter-patient variability. An adjusted intraoperative drug administration allows faster recovery and provides post-operative side-effect mitigation METHODS: BIS evolution and surgery-recorded propofol infusion data of a group of 60 adult patients (30 males/30 females) with ASA I/II physical status were used to test a real time PK/PD compartmental model. This new algorithm tunes three model parameters (ce50, γ and ke0), minimizing a performance function online. RESULTS: The error in the BIS signal predicted by the real time PK/PD model was smaller than the error measured with fixed parameter equations. This model shows that ce50, γ and ke0 change with time and patients, given a mean (95% confidence interval) of 3.89 (3.52-4.26)mg/l, 4.63 (4.13-5.13) and 0.36 (0.31-0.4)min(-1), respectively. CONCLUSIONS: The real time PK/PD model proposed provides a closer description of the patient real state at each sample time. This allows for greater control of the drug infusion, and thus the quantity of drug administered can be titrated to achieve the desired effect for the desired duration, and reduce unnecessary waste or post-operative effects.


Subject(s)
Anesthesia/methods , Models, Biological , Propofol/administration & dosage , Propofol/pharmacokinetics , Adult , Female , Humans , Male
8.
Anaesthesia ; 68(11): 1132-40, 2013 Nov.
Article in English | MEDLINE | ID: mdl-23992529

ABSTRACT

Using Schnider's pharmacokinetic model, propofol pharmacodynamics were modelled during total intravenous anaesthesia. The method involved adjusting a pharmacokinetic/pharmacodynamic model according to data obtained from 42 patients having operative procedures with remifentanil analgesia. Parameters Ce50 and γ were estimated for induction and maintenance by analysing patients' bispectral index. The pharmacodynamic models were different for induction and maintenance. The mean (95% CI) Ce50 for induction and maintenance was Ce50 = 3.35 (2.79-3.91) mg.l(-1) and 2.23 (1.95-2.51) mg.l(-1) , respectively, with a higher concentration required to achieve the same effect during induction, even during remifentanil co-administration. During induction and maintenance, γ was 1.24 (1.44-2.00) and 1.58 (1.32-1.84), respectively. As γ is related to the concentration-effect slope, patient response is accentuated during maintenance compared with induction. The influence of sex and age on the model was analysed. Sex had no significant influence on the model, although a linear relation was found between age and Ce50 .


Subject(s)
Anesthesia, Intravenous/methods , Anesthetics, Intravenous/pharmacokinetics , Electroencephalography/methods , Piperidines/pharmacokinetics , Propofol/pharmacokinetics , Adult , Female , Humans , Male , Monitoring, Intraoperative/methods , Remifentanil , Sex Factors
10.
Euro Surveill ; 14(49)2009 Dec 10.
Article in English | MEDLINE | ID: mdl-20003907

ABSTRACT

In Andalusia, Spain, the pandemic influenza A(H1N1)v virus has spread throughout the community, being the dominant influenza strain in the season so far. The current objective of the Andalusia Health Service is focussed on the mitigation of the health and social impact by appropriate care of the patients at home or in health centres. The 2009-10 seasonal influenza epidemic started early compared with to previous seasons. This article analyses the influenza A(H1N1)v situation in Andalusia until the week 39/2009.


Subject(s)
Disease Outbreaks/statistics & numerical data , HIV Infections/epidemiology , Influenza A Virus, H1N1 Subtype , Influenza, Human/epidemiology , Seasons , Female , Humans , Incidence , Male , Population Surveillance , Risk Assessment , Risk Factors , Spain/epidemiology
13.
Clin Microbiol Infect ; 13(10): 1008-11, 2007 Oct.
Article in English | MEDLINE | ID: mdl-17711486

ABSTRACT

Although asymptomatic carriers of Pneumocystis jirovecii with cystic fibrosis (CF) have been described previously, the molecular epidemiology of P. jirovecii in CF patients has not yet been clarified. This study identified the distribution and dynamic evolution of P. jirovecii genotypes based on the mitochondrial large-subunit (mt LSU) rRNA gene. The mt LSU rRNA genotypes of P. jirovecii isolates in 33 respiratory samples from CF patients were investigated using nested PCR and direct sequencing. Three different genotypes were detected: 36.3% genotype 1 (85C/248C); 15.1% genotype 2 (85A/248C); 42.4% genotype 3 (85T/248C); and 6% mixed genotypes. Patients studied during a 1-year follow-up period showed a continuous colonisation/clearance cycle involving P. jirovecii and an accumulative tendency to be colonised with genotype 3.


Subject(s)
Carrier State/epidemiology , Cystic Fibrosis/complications , Molecular Epidemiology , Pneumocystis carinii/genetics , Pneumonia, Pneumocystis/epidemiology , Adolescent , Adult , Carrier State/microbiology , Child , Child, Preschool , Female , Genotype , Humans , Infant , Male , Mitochondria/genetics , Pneumocystis carinii/classification , Pneumonia, Pneumocystis/microbiology , Polymerase Chain Reaction , RNA, Ribosomal/genetics , Sequence Analysis, DNA , Spain/epidemiology
14.
Infect Control Hosp Epidemiol ; 27(11): 1249-51, 2006 Nov.
Article in English | MEDLINE | ID: mdl-17080385

ABSTRACT

We describe an outbreak of nosocomial endophthalmitis due to a common source, which was determined to be trypan blue solution prepared in the hospital's pharmacy service. We assume that viable bacteria probably gained access to the trypan blue stock solution during cooling after autoclaving. The temporal cluster of Pseudomonas aeruginosa endophthalmitis was readily perceived on the basis of clinical and microbiological findings, and an exogenous source of contamination was unequivocally identified by means of DNA fingerprinting.


Subject(s)
Cross Infection/epidemiology , Disease Outbreaks , Endophthalmitis/epidemiology , Pseudomonas Infections/epidemiology , Pseudomonas aeruginosa/isolation & purification , Aged , Buffers , Cataract/diagnosis , Coloring Agents/administration & dosage , Cross Infection/etiology , Cross Infection/microbiology , DNA Fingerprinting/methods , Endophthalmitis/etiology , Endophthalmitis/microbiology , Equipment Contamination , Female , Humans , Male , Middle Aged , Pseudomonas Infections/etiology , Pseudomonas Infections/microbiology , Pseudomonas aeruginosa/classification , Pseudomonas aeruginosa/genetics , Trypan Blue/administration & dosage
15.
Clin Microbiol Infect ; 11(12): 1012-5, 2005 Dec.
Article in English | MEDLINE | ID: mdl-16307556

ABSTRACT

Pneumocystis jirovecii colonisation may occur among cystic fibrosis (CF) patients because of their underlying pulmonary disease. A wide epidemiological analysis was performed among CF patients from Spain to assess the prevalence of P. jirovecii colonisation and the distribution of different genotypes. P. jirovecii was identified by nested PCR targeting the mitochondrial large-subunit rRNA gene from sputum samples or oropharyngeal washes. The genotype was determined by direct sequencing. The prevalence of P. jirovecii colonisation among 88 consecutive CF patients was 21.5%. The polymorphisms identified were 85C/248C (45.4%), 85T/248C (27.2%) and 85A/248C (18.1%); in one case, a mix of genotypes was found. Colonisation was more frequent in subjects aged < 18 years (25.5% vs. 15.1%). Among the patients studied, 20.8% received treatment with azithromycin; all of these patients were colonised with P. jirovecii, but none developed Pneumocystis pneumonia (PcP) during a 1-year follow-up period. Concordance in the colonisation status of siblings suggested a common source of infection or person-to-person transmission.


Subject(s)
Cystic Fibrosis/complications , Pneumocystis carinii/genetics , Pneumonia, Pneumocystis/epidemiology , Adolescent , Adult , Child , Child, Preschool , Female , Genotype , Humans , Infant , Male , Pneumocystis carinii/growth & development , Pneumocystis carinii/isolation & purification , Pneumonia, Pneumocystis/complications , Pneumonia, Pneumocystis/microbiology , Prevalence , Spain/epidemiology
18.
J Colloid Interface Sci ; 194(2): 356-63, 1997 Oct 15.
Article in English | MEDLINE | ID: mdl-9398417

ABSTRACT

The interaction between cetyl pyridinium chloride and different-molecular-weight poly(vinylpyrrolidone) (PVP) and poly(ethylene glycol) (PEG) polymers has been investigated by means of electrical conductivity and fluorescence probing. No interaction between the low-molecular-weight PVP polymers and the surfactant was detected, whereas a significant interaction was observed between high-molecular-weight PVP polymers or PEG polymers and cetyl pyridinium chloride. The results indicate that polymer-surfactant aggregates start to form at a surfactant concentration higher than the critical micelle concentration of micelles without polymers. In contrast, the degree of ionization and the interface polarity decrease as compared with values of micelles without polymers. The Gibbs free energy associated with the interaction was also calculated. The values show that the addition of polymers stabilizes polymer-surfactant aggregates. Copyright 1997 Academic Press. Copyright 1997Academic Press

19.
Rev Enferm ; 20(230): 55-8, 1997 Oct.
Article in Spanish | MEDLINE | ID: mdl-9416197

ABSTRACT

The objectives of this article are to estimate the percentage of people who fail to receive their second and third dose of the antitetanus vaccination, find a relation between public health information and the reason for administering the vaccine with the percentage of non-compliers, and to estimate the percentage of patients who fail to receive their third dose after a six month waiting period. This study was designed with a multiple follow-up. This study took place at a Primary Health care center: E.A.P. Barcelona II in Móstoles, Madrid. Patients included all those people who met the requirements for the vaccination; in this study there were 452 persons. STATISTICS AND MAIN RESULTS INCLUDE: The percentage of noncompliance with second and third doses was 59.7% (195% (54.4%-65.0%)) There was a higher percentage of noncompliance in the group which received sanitary information, 61.8% while the group which received basic information registered a 54% rate (p > 0.05). The percentage who failed to continue their doses if first administered for a cut was 60.3% against a 59.0% rate for those caught in doctors check-ups, (p > 0.05). The proportion of noncompliance due to the 6 month waiting period was 46.9% (IC95 (37.8-56%)). CONCLUSION: This study did not demonstrate that greater sanitary information coupled with a cut contributed to a higher compliance to the convention vaccination pattern. We note the percentage of noncompliance for the third dose following a 12 month pattern was 55.3% against 46.9% in the six month pattern; this leads us to plan a further study. One can include that more than half the people do not comply when they should for the administration of the antitetanus vaccine. We feel it is necessary to improve the means through which people remember they need to take their antitetanus vaccine's doses.


Subject(s)
Patient Compliance , Tetanus Toxoid , Humans
SELECTION OF CITATIONS
SEARCH DETAIL
...