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Carles Codina

Publications and source records attributed to Carles Codina.

At least 19 recordsLinked to original sources
PubMed2006

Are higher vancomycin doses needed in ventricle-external shunted patients?

OBJECTIVE: Hydrocephalus is usually resolved by diverting cerebrospinal fluid through a surgically implanted intra-ventricular catheter (shunt). The aim of this study was to characterize vancomycin pharmacokinetic (PK) parameters and optimal dosage in shunted patients under vancomycin treatment. SETTING: Intensive Care and Neurosurgical Units. University Hospital. METHODS: Retrospective data of vancomycin blood concentrations, demographics and biochemical parameters, from a Therapeutic Drug Monitoring (TDM) program, in ventricle-external shunted patients (Group A) and controls (Group B) were collected. In all subjects, several blood samples at steady state conditions were drawn. Individual PK parameters such as drug clearance (CL) and volume of distribution (V) were estimated by using an one-compartmental PK model and later, dosage regimens were individually adjusted by Bayesian analysis. The obtained CL and V mean +/- standard deviation were compared between both groups (A versus B). Vancomycin dosage regimens between both groups were also compared. MAIN OUTCOME MEASURES: Patients demographics, clinical records, creatinine clearance by Cockcroft-Gault, vancomycin blood levels, vancomycin pK parameters and optimal initial IV vancomycin dosage. RESULTS: Forty-five patients were included in the study: 15 patients in group A and 30 subjects in group B. Significant differences between CL(A) and CL(B) means were observed, while not between V(A) and V(B). In shunted patients, the required vancomycin daily dose to reach target concentrations was significantly higher than the dose needed in the control group (49.25 +/- 12.28 mg/kg/day vs. 31.74 +/- 6.70 mg/kg/day; P < 0.0005). CONCLUSIONS: Greater vancomycin clearance was found in our shunted patients, thus they required higher vancomycin daily doses compared to the control group. Consequently, vancomycin TDM in shunted patients should be advisable in order to guarantee antibiotic blood concentrations within the recommended therapeutic range.

Adult↗
PubMed2006

[Antiretroviral therapy of HIV infection: duration and reasons for changing the first therapeutic regimen in 518 patients].

BACKGROUND AND OBJECTIVE: Different combinations of antiretroviral drugs are used as initial HIV therapy but comparative studies between them are not frequent. The objectives of this study are to determine the median duration of different therapy combinations in naive patients between 1998-2000 and the main reasons for changing or stopping this first antiretroviral therapy (ARVT). PATIENTS AND METHOD: This study included a total of 518 naive patients who began antiretroviral therapy patients from 1998-2000. Using a Kaplan-Meier analysis the median duration of different combinations was determined. In addition, the main reasons for changing or stopping this first treatment were analysed. RESULTS: First ARVT median duration was 427 days (IQR: 114-890). 47% of patients stopped their first therapy due to adverse effects, 6% voluntarily withdrew from it, in 9% of patients the therapy was not effective and 15% of them were lost of follow up. Only 9% of them continued with the same ARVT at the end of the study but if we add 7% of treatment simplifications we can consider 16% of first ARVT successful. CONCLUSIONS: A median duration of 427 days, similar to other studies, is shorter than we would prefer for HIV, a condition that requires continuous treatment. On the other hand, the study corroborates that secondary effects are the principal problem associated with ARVT.

Adult↗
PubMed2006

Comparison of antimicrobial cycling and mixing strategies in two medical intensive care units.

OBJECTIVE: To compare a mixing vs. a cycling strategy of use of anti-Pseudomonas antibiotics on the acquisition of resistant Gram-negative bacilli in the critical care setting. DESIGN: Prospective, open, comparative study of two strategies of antibiotic use. SETTING: Two medical intensive care units of a university hospital. PATIENTS: A total of 346 patients admitted for >or=48 hrs to two separate medical intensive care units during an 8-month period. INTERVENTIONS: Patients, who according to the attending physician's judgment required an anti-Pseudomonas regimen, were assigned to receive cefepime/ceftazidime, ciprofloxacin, a carbapemen, or piperacillin-tazobactam in this order. "Cycling" was accomplished by prescribing one of these antibiotics during 1 month each. "Mixing" was accomplished by using the same order of antibiotic administration on consecutive patients. Interventions were carried out during two successive 4-month periods, starting with mixing in one unit and cycling in the other. MEASUREMENTS AND MAIN RESULTS: Swabbing of nares, pharynx, and rectum and culture of respiratory secretions were obtained thrice weekly. The main outcome variable was the proportion of patients acquiring enteric or nonfermentative Gram-negative bacilli resistant to the antibiotics under intervention. The scheduled cycling of antibiotics was only partially successful. Although the expected antibiotic was the most prevalent anti-Pseudomonas agent used within the corresponding period, it never accounted for >45% of all anti-Pseudomonas antimicrobials administered. During mixing, a significantly higher proportion of patients acquired a strain of Pseudomonas aeruginosa resistant to cefepime (9% vs. 3%, p = .01), and there was a trend toward a more frequent acquisition of resistance to ceftazidime (p = .06), imipenem (p = .06), and meropenem (p = .07). No differences in the rate of acquisition of potentially resistant Gram-negative bacilli or incidence of intensive care unit-acquired infections and infections due to particular organisms were observed. CONCLUSIONS: In critically ill medical patients, a strategy of monthly rotation of anti-Pseudomonas beta-lactams and ciprofloxacin may perform better than a strategy of mixing in the acquisition of P. aeruginosa resistant to selected beta-lactams.

APACHE↗
PubMed2005

Alkaloids from Nerine filifolia.

The novel compounds N-demethylbelladine, 6alpha-methoxybuphanidrine and filifoline, in addition to five known alkaloids, and phenol have been isolated from fresh bulbs of Nerine filifolia (Amaryllidaceae). The structure and stereochemistry of the compounds were determined by physical and spectroscopic methods, including 1D and 2D NMR and mass spectroscopic techniques. An unusual circular dichroism response from filifoline has required a semi-synthetic derivatisation strategy towards key C-11endo analogues of the beta-crinane representative ambelline in which the nature of substituents was observed to have a profound effect on molecular ellipticity. Filifoline was not cytotoxic to myoblast (L6) cells and exhibited no anti-protozoal activity in an in vitro screen against four different parasitic protozoa.

Amaryllidaceae Alkaloids↗
PubMed2005

Acylated quercetagetin glycosides with antioxidant activity from Tagetes maxima.

The fractionation of a methanolic extract of Tagetes maxima guided for antioxidant activity resulted in the isolation of three acylated quercetagetin glycosides, quercetagetin-7-O-(6-O-caffeoyl-beta-D-glucopyranoside), quercetagetin-7-O-(6-O-p-coumaroyl-beta-D-glucopyranoside) and quercetagetin-7-O-(6-O-galloyl-beta-D-glucopyranoside), as well as four known flavonoid glycosides. The structural elucidation was accomplished by spectroscopic methods (ESI-MS/MS and NMR). The antioxidant activity of fractions and isolated compounds was determined by checking the scavenging activity against three different radicals: 2,2-diphenyl-1-picrylhydrazyl free radical (DPPH*), hydroxyl (*OH), and superoxide (O2*-). The three isolated compounds exhibited a high radical scavenging activity in comparison with reference compounds.

Acylation↗
PubMed2004

Disposition of instilled versus nebulized tobramycin and imipenem in ventilated intensive care unit (ICU) patients.

BACKGROUND: Delivery of antibiotics to the lower respiratory tract could potentially achieve antimicrobial bronchial drug concentrations without toxicity. AIM: To assess bronchial and serum concentrations of imipenem or tobramycin obtained by nebulization or instillation in critically ill mechanically ventilated patients. METHODS: Prospective randomized open trial. Eighteen patients ventilated for more than 48 h were included. Two doses of imipenem/cilastatin (1000/500 mg) separated by 8 h, or two doses of tobramycin 200 mg separated by 12 h were randomly nebulized or instilled into the tracheal tube. Five bronchoaspirates (two bronchoscopic, three blind) and five blood samples were collected on a timed schedule after the second dose. Respiratory and serum samples were analysed by HPLC, and a subset of blood samples was also evaluated by enzyme-immunoassay. RESULTS: When instilled, imipenem/cilastatin obtained higher concentrations in respiratory secretions than when nebulized (P=0.022, 1 h after the last dose; P=0.029, 2 h after the last dose). Tobramycin showed equally high concentrations when nebulized or instilled. Instillation of tobramycin may result in significant accumulation in patients with renal failure. CONCLUSIONS: High bronchial concentrations of imipenem could only be achieved by instillation, whereas tobramycin seems suitable for both modes of administration. Instillation of these antibiotics is a safe procedure that achieves high drug concentrations in respiratory secretions.

Administration, Inhalation↗
PubMed2004

Separation and characterization of phenolic compounds in fennel (Foeniculum vulgare) using liquid chromatography-negative electrospray ionization tandem mass spectrometry.

Liquid chromatography (LC) diode array detection (DAD) coupled to negative electrospray ionization (ESI) tandem mass spectrometry (MS/MS) was used for the rapid and sensitive identification of water-soluble phenolic compounds in fennel waste. The plant material was first extracted and then chromatographed on Sephadex LH-20 to afford seven fractions, each of them being subjected to LC-MS analysis. Identification of the compounds was carried out by interpretation of UV, MS, and MS/MS spectra. Forty-two phenolic substances were identified, 27 of which had not previously been reported in fennel, including hydroxycinnamic acid derivatives, flavonoid glycosides, and flavonoid aglycons.

Chemical Fractionation↗
PubMed2004

Bioguided isolation and identification of the nonvolatile antioxidant compounds from fennel (Foeniculum vulgare Mill.) waste.

A bioguided isolation of an aqueous extract of fennel waste led to the isolation of 12 major phenolic compounds. Liquid chromatography coupled to atmospheric pressure chemical ionization mass spectrometry (LC/UV/APCI-MS) combined with spectroscopic methods (NMR) was used for compound identification. Radical scavenging activity was tested using three methods: DPPH*, superoxide nitro-blue tetrazolium hypoxanthine/xanthine oxidase, and *OH/luminol chemiluminescence. In addition to products described in the literature, eight antioxidant compounds were isolated and identified for the first time in fennel: 3-caffeoylquinic acid, 4-caffeoylquinic acid, 1,5-O-dicaffeoylquinic acid, rosmarinic acid, eriodictyol-7-O-rutinoside, quercetin-3-O-galactoside, kaempferol-3-O-rutinoside, and kaempferol-3-O-glucoside. The structures of eriodictyol-7-O-rutinoside and quercetin-3-O-glucuronide were completely elucidated by two-dimensional NMR experiments. The isolated compounds exhibited a strong antiradical scavenging activity, which may contribute to the interpretation of the pharmacological effects of fennel.

Antioxidants↗
PubMed2004

Qualitative analysis of phenolic compounds in apple pomace using liquid chromatography coupled to mass spectrometry in tandem mode.

The occurrence of phenolic compounds in apple residues resulting from the juice industry was investigated to provide an alternative use for this raw material. For the identification of these compounds, liquid chromatography coupled to ionspray mass spectrometry in tandem mode (LC/MS/MS) with negative ion detection was used. The residues were first extracted and then chromatographed on Sephadex LH-20 to yield 13 fractions. Positive identification of the compounds was based on their retention times and mass spectra in full scan mode (MS), and in different MS/MS modes (product ion scan, precursor ion scan and neutral loss scan). In this way, 60 compounds, including cinnamic and benzoic acid derivatives and flavonoids, were identified, some of them not previously reported in apple waste.

Chromatography, High Pressure Liquid↗
PubMed2004

Characterization of acylated flavonoid-O-glycosides and methoxylated flavonoids from Tagetes maxima by liquid chromatography coupled to electrospray ionization tandem mass spectrometry.

Liquid chromatography coupled to negative electrospray ionization (ESI) tandem mass spectrometry (MS/MS) employing a triple quadrupole mass spectrometer was used in the structural determination of acylated flavonoid-O-glycosides and methoxylated flavonoids occurring in Tagetes maxima. The compounds were identified by experiments in full scan mode (MS), and tandem mass experiments (MS/MS) of precursor ion scan, product ion scan, and neutral loss scan modes. In order to characterize the aglycones of the flavonoid glycosides, in-source fragmentation of the deprotonated molecule [M-H]- followed by product ion scan of the resulting aglycone [A-H]- were performed. This combined approach allowed the identification of 51 phenolic compounds, including flavonoid-O-glycosides acylated with galloyl, protocatechuoyl, coumaroyl or caffeoyl groups, methoxylated flavonoids, and hydroxycinnamic acid and phenolic acid derivatives, none of them previously reported in Tagetes maxima.

Chromatography, High Pressure Liquid↗
PubMed2004

Investigation of Lepechinia graveolens for its antioxidant activity and phenolic composition.

A bioguided separation of Lepechinia graveolens (Reg.) Epling. (Lamiaceae) for antioxidant activity was carried out. The ethyl acetate fraction (EAF) from the methanolic extract was chromatographed on Sephadex LH-20 affording five active fractions. The radical scavenging activity of each fraction, as well as that of the isolated compounds, was tested using three different methods. The major isolated antioxidant compounds were identified as luteolin-7-O-glucuronide, rosmarinic acid, and rosmarinic acid methyl ester by means of 1H and 13C NMR and mass spectrometry. Twenty other minor phenolic compounds were determined by liquid chromatography-negative electrospray ionization tandem mass spectrometry. They included hydroxycinnamic acid derivatives, flavonoids and phenolic diterpenes. The major phenolic compound was found to be rosmarinic acid, which was quantitatively determined by high-performance liquid chromatography (HPLC)-diode array detector (DAD). The content of rosmarinic acid was 2.8% (referred to dry weight), this amount being around 30% of the total phenolic content (TPH) of the crude extract. It can be concluded that the antioxidant activity of Lepechinia graveolens was mainly due to rosmarinic acid, which allows this plant species to be considered as a potential new source of this well known natural antioxidant.

Antioxidants↗
PubMed2004

Improved production of galanthamine and related alkaloids by methyl jasmonate in Narcissus confusus shoot-clumps.

Liquid-shake cultured shoot-clumps of Narcisus confussus were treated with the commonly used biotic elicitors methyl jasmonate, arachidonic acid, chitosan and salicylic acid. The effects of these compounds on the growth of the explants, as well as on the amount of the alkaloids released to the liquid culture medium and accumulated in the tissues at the end of the experiment were studied. The obtained results showed that, in general, high doses of these compounds had a negative effect on the growth of the explants, particularly the salicylic acid. On the contrary, the addition of methyl jasmonate, mainly at 25 microM, promoted the release of galanthamine and other related alkaloids to the liquid medium in proportions of up to 300% in relation to the control explants, and also their accumulation in tissues. The other elicitors studied did not have any interesting effects on the production of these Amaryllidaceae-type alkaloids.

Acetates↗
PubMed2003

Investigation of Bolivian plant extracts for their radical scavenging activity and antioxidant activity.

Fifty-four different extracts of nine Bolivian plants belonging to the family Asteraceae were evaluated for their radical scavenging activity by the DPPH*, NBT/hypoxanthine superoxide, and (*)OH/luminol chemiluminescence methods, and for their antioxidant activity by the beta-carotene bleaching test. The total phenolic content was also determined by the Folin-Ciocalteu method, and the oxidative stability by the Rancimat test. Both remarkably high phenolic content and radical scavenging and antioxidant activities were found mainly in the ethyl acetate fractions among the different plant extracts. Some ethyl acetate and even some defatted crude extracts exhibited activities comparable to those of commercial extracts/compounds, thus making it possible to consider some of the studied plants as a potential source of antioxidants of natural origin.

Antioxidants↗
PubMed2003

Identification of phenolic compounds in artichoke waste by high-performance liquid chromatography-tandem mass spectrometry.

A new fast and efficient method combining liquid chromatography coupled to ionspray mass spectrometry in tandem mode with negative ion detection is described for the qualitative analysis of artichoke waste. Forty-five phenolic compounds were identified on the basis of their mass spectra in full scan mode, mass spectra in different MS-MS modes, and retention times compared with those of available reference substances. The major compounds were found to be both caffeoylquinic and dicaffeoylquinic acids, luteolin glucuronide, luteolin galactoside, quercetin, and some quercetin glycosides.

Chromatography, High Pressure Liquid↗
PubMed2003

[Characteristics of antiviral drugs].

This article summarizes the principal characteristics of the drugs used to treat viral infections, with the exception of human immunodeficiency virus infection. It includes antiviral agents active against herpes virus, cytomegalovirus, hepatitis B and C virus, and respiratory viruses, such as influenza and respiratory syncytial virus. Dosage according to the indication, dose adjustment in the case of renal or hepatic insufficiency, significant pharmacokinetic characteristics, and the main adverse effects and interactions are described.

Antiviral Agents↗
PubMed2003

Seasonal and spatial variations of alkaloids in Merendera montana in relation to chemical defense and phenology.

Merendera montana (Liliaceae) is an endemic plant broadly, but exclusively, occurring in the Iberian Peninsula where it is one of the most abundant species in rangelands grazed by sheep and on the routes used by migrating sheep herds. In spite of showing a peculiar phenology adapted to Mediterranean regions (leaves remain green from fall to spring and are absent in summer), this species has also successfully colonized high altitude environments (up to 2300 m), and abundant populations can be found in montane and subalpine pasturcs. Chemical analysis has shown a high forage quality as well as the presence of tropolone alkaloids (similar to other species of the genus Merendera), mainly colchicine, 3-demethylcolchicine, and colchicoside. In general terms, the alkaloid content was significantly lower in the subterranean corms than in the leaves. No remarkable seasonal variations in total alkaloids was found, although an increase of colchicoside in the corms and a decrease of colchicine was noted in summer. Both chemical deterrents and phenology could be the cause of the widespread ecological adaptation of Merendera montana. The alkaloid content would prevent intake by wild herbivores during winter, while the absence of aerial organs in summer, coinciding exactly with the highest domestic herbivore pressure, would permit this species to colonize rich soil habitats where there is low plant competition.

Adaptation, Physiological↗
PubMed2003

Anti-human immunodeficiency virus type 1 (HIV-1) activity of lectins from Narcissus species.

Mannose-specific lectins (MSLs) were isolated from bulbs of fifteen wild Narcissus species growing in Spain and assayed for their HIV-1 infection inhibitory activity in MT-4 cells and compared to the Narcissus pseudonarcissus agglutinin (NPA), the commercially available MSL obtained from daffodils. Almost all the tested MSLs were found to be active, showing EC50 values (microg/mL) similar to that of NPA, with some being comparable to those obtained with dextran sulfate without significant cytotoxicity. However, on a molar basis almost all of the MSLs tested exhibited lower EC50 values than dextran sulfate whilst six MSLs had values lower than AZT. The most efficacious anti-HIV-1 activity was exhibited by the Narcissus tortifolious MSL, which was 10- (microg/mL) and 100- (molarity) fold more potent than dextran sulfate. Significantly, although this MSL was 15-fold less potent than AZT in terms of quantity (microg/mL), it was 68-fold more potent on a molar basis. The antiviral indices, a ratio of the concentrations that produce cytotoxicity and HIV-1 replication, were calculated and three of the MSLs, N. confusus, N. leonensis and N. tortifolius reported 1.5-, 2- and 8.5-fold greater AI values than dextran sulfate or AZT. Comparison of MSL haemagglutination activities (HAA) to their anti-HIV-1 activities showed that there was no significant correlation. It was suggested that this may be due to a dissociation between both activities as a consequence of multiple isolectin composition.

Anti-HIV Agents↗