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E Rodríguez

Publications and source records attributed to E Rodríguez.

At least 37 records · Page 2Linked to original sources
PubMed2004

Minor interspecies variations in the sequence of the gp53 TSL-1 antigen of Trichinella define species-specific immunodominant epitopes.

Among the Trichinella TSL-1 antigens, whose antigenicity is generally due mainly to tyvelose-containing epitopes, gp53 is unusual in that its antigenicity is due mainly to protein epitopes. In the present study we mapped two of these epitopes, recognized by monoclonal antibodies (mAbs) that specifically recognize gp53 from all encysting Trichinella species (mAb US9), or gp53 from Trichinella spiralis alone (mAb US5). Based on previously published sequences of this glycoprotein [Mol. Biochem. Parasitol. 72 (1995) 253], in this study, we cloned the full gp53 cDNA from a new strain, Trichinella britovi (ISS 11; AN: ), and from another T. spiralis isolate (ISS 115; AN: ). The gp53 sequence comprised an ORF of 1239bp, coding for 412 amino acids, with 61 nucleotide differences (resulting in 38 residue changes) between the two species. Mapping of US5- and US9-recognized epitopes was undertaken through the construction and expression in the pGEX4T vector of truncated gp53 peptides, and by the construction of peptides derived from the antigenic regions. The epitope recognized by mAb US9 was a linear peptide of 8 residues, 33Met- 40Ser, located in the amino-terminal region, while the corresponding epitope recognized by mAb US5 was a 47-amino acid sequence containing two alpha-helix regions flanked by random coils, 290Thr- 336Lys. Molecular modeling of these peptides seems to indicate that recognition of the US9 epitope depends on the presence of two available hydroxyl groups provided by one methionine and one serine on T. spiralis gp53 (not present on Trichinella pseudospiralis gp53). Additionally, the stability of the US5 epitope seems to depend on correct folding of the 47-amino acid sequence (only present in T. spiralis). The relevance of these findings for understanding the antigenic recognition of Trichinella TSL-1 antigens, and for further studies to investigate possible function(s) of gp53 in Trichinella, is discussed.

Agammaglobulinaemia Tyrosine Kinase↗
PubMed2004

Isolation and characterization of a lipoxygenase from Pseudomonas 42A2 responsible for the biotransformation of oleic acid into ( S )-( E )-10-hydroxy-8-octadecenoic acid.

The isolation of a new lipoxygenase-like (LOX-like) enzyme from Pseudomonas 42A2 and its characterization is described. The enzyme, located in the periplasm of the cell, which contained 0.55 mol of Fe2+ per mol of protein, is monomeric and has a molecular mass of 45 kDa. In the presence of oxygen, the enzyme converts oleic acid into (E)-10-hydroperoxy-8-octadecenoic acid (HPOD), which decomposes to the corresponding (E)-10-hydroxy-8-octadecenoic acid (HOD). The absolute configuration of this acid was determined as S on the basis of exciton-coupled CD data, and specific rotation and NMR analysis of the corresponding p -bromobenzoate derivative. The reaction in vivo leads to the dihydroxy derivative (E)-7,10-dihydroxy-8-octadecenoic acid (DHOD), so that the three hydroxy-fatty acids can be isolated from the culture medium. The activity of the enzyme was optimal between 25 and 30 degrees C and 44% of its activity still remained at 55 degrees C. Its optimal pH is 8.5-9; and the presence of magnesium ions increased LOX activity by 1.5. The activity of the LOX is highest in unsaturated fatty acids containing double bonds in position 9 (oleic, linoleic and linolenic acids), linoleic acid being preferred (100% activity) over linolenic (60.4%) and oleic acids (46%). However, kinetic studies showed that the affinity of the enzyme is similar for the three substrates.

Biotransformation↗
PubMed2004

Q fever: a new cause of 'doughnut' granulomatous lobular panniculitis.

Q fever is an uncommon zoonotic rickettsial disease with no exanthem or specific cutaneous lesions. Only nonspecific cutaneous involvement has been reported to date. A 69-year-old Spanish woman with chronic myelogenous leukaemia developed fever and two subcutaneous nodules. The patient complained of extreme pain. Biopsy revealed a granulomatous lobular panniculitis with a characteristic 'fibrin ring' or 'doughnut' appearance: fibrin and inflammatory cells arranged around a central clear space. Changes of membranous lipodystrophy were also found. Q fever serological studies were positive. Our patient had panniculitis with singular histopathological features. These histopathological changes have been described in liver and bone marrow of patients with Q fever. To the best of our knowledge, this cutaneous involvement due to Q fever has not previously been described in the literature.

Aged↗
PubMed2004

Cellular effects of monohydrochloride of L-arginine, N-lauroyl ethylester (LAE) on exposure to Salmonella typhimurium and Staphylococcus aureus.

AIMS: Here we study the effect of monohydrochloride of L-arginine, N(alpha)-lauroyl ethylester (LAE), a cationic preservative derived from lauric acid and arginine, on the cell envelopes of Salmonella typhimurium and Staphylococcus aureus at sub-lethal concentration such as their respective minimal inhibitory concentrations, 32 and 8 microg ml(-1), respectively. METHODS AND RESULTS: Bacterial populations were studied by using transmission electron and fluorescence microscopy (TEM and FM), flow cytometry (FC) and ion-flux across the cellular membrane. Cell integrity was altered mainly in the outer membrane of S. typhimurium, but there was no significant change in the cytoplasm. However, in Staph. aureus, clear zones, abnormal septation and mesosome-like structures were observed in the cytoplasm. Bacterial populations were double-stained with propidium iodide (PI) and SYTO-13 for FC analysis. In S. typhimurium the proportion of damaged cells after 24 h was 97% and in Staph. aureus 56.3%. LAE induced transmembrane ion flux, the increase of potassium leakage after 30 min of contact was 7.7 and 3.34 microg ml(-1) for Staph. aureus and S. typhimurium, respectively. Membrane disruption was detected by measuring the proton flow across the membrane. CONCLUSIONS: Disturbance in membrane potential and structural changes was caused by LAE, although cells were not disrupted. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first time the cellular effects of LAE on bacterial cells were studied.

Anti-Infective Agents↗
PubMed2004

Preventive effects of D-004, a lipid extract from Cuban royal palm (Roystonea regia) fruits, on testosterone-induced prostate hyperplasia in intact and castrated rodents.

Benign prostatic hyperplasia (BPH) is the noncancerous, uncontrolled growth of prostate gland cells and stroma that can cause difficulty urinating. Fruit lipid extracts from saw palmetto, a palm from the Arecaceae family, are used for BPH management. The Cuban royal palm, Roystonea regia, is also a member of the Arecaceae family and therefore it was appropriate to investigate the protective effects of Roystonea regia fruit lipid extracts on prostatic hyperplasia. The aim of this study was to investigate whether D-004, a lipid extract from Roystonea regia fruits, prevented testosterone-induced PH in castrated and intact rodents. Two series of experiments were performed. The first one was conducted in castrated and intact rats, distributed into five groups of 10 rats per group. The negative control group was injected with soy oil and treated orally with vehicle, while the four testosterone-injected groups were treated with vehicle (positive control), D-004 100, 200 and 400 mg/kg, respectively. The other experiment was conducted in castrated and intact mice. These were distributed into four groups of 10 mice per group: a negative control group and three testosterone-injected groups, of which one was a positive control, while two received D-004 200 and 400 mg/kg, respectively. At study completion, the rodents were sacrificed and prostates removed and weighed. D-004 at doses of 100, 200 and 400 mg/kg significantly and dose-dependently prevented prostate enlargement in intact and castrated rats and mice. The percentage inhibitions obtained in mice were greater: 77% and 84% for intact and castrated mice, respectively. D-004 therapy did not affect body weight. It is concluded that D-004 administered orally significantly prevented testosterone-induced prostate enlargement in both intact and castrated rodents, indicating that an endogenous supply of testosterone is not necessary to observe such an effect The results of the present investigation support further studies of D-004 on experimental models of prostatic hyperplasia.

Animals↗
PubMed2003

Coupling solid-phase microextraction and high-performance liquid chromatography for direct and sensitive determination of halogenated fungicides in wine.

A solid-phase microextraction (SPME) method coupled to high-performance liquid chromatography with diode array detection (HPLC-DAD) for the analysis of six organochlorine fungicides (nuarimol, triadimenol, triadimefon, folpet, vinclozolin and penconazole) in wine was developed. For this purpose, polydimethylsiloxane-divinylbenzene-coated fibers were utilized and all factors affecting throughput, precision, and accuracy of the SPME method were investigated and optimized. These factors include: matrix influence, extraction and desorption time, percentage of ethanol, pH, salt effect and desorption mode. The performed analytical procedure showed detectability ranging from 4 to 27 microg l(-1) and precision from 2.4 to 14.2% (as intra-day relative standard deviation, RSD) and 4.7-25.7% (as inter-day RSD) depending on the fungicide. The results demonstrate the suitability of the SPME-HPLC-DAD method to analyze these organochlorine fungicides in red wine.

Chromatography, High Pressure Liquid↗
PubMed2003

Reuterin production by lactobacilli isolated from pig faeces and evaluation of probiotic traits.

AIMS: To determine the production of reuterin by lactobacilli isolates from pig faeces and to evaluate their potential as probiotic bacteria. METHODS AND RESULTS: Twenty-eight of 165 lactobacilli isolates produced reuterin in the presence of glycerol. Six isolates yielding high levels of reuterin with respect to type strain Lactobacillus reuteri CECT 925T were identified as Lact. reuteri. They were able to survive at pH 3 and subsequent exposure to cholic acid or oxgall, and presented bile salt hydrolase and bacteriocin-like activities. CONCLUSIONS: Reuterin production is a frequently found trait among lactobacilli isolated from pig faeces. Selected Lact. reuteri isolates were able to survive at conditions likely to be encountered throughout the gastrointestinal tract. SIGNIFICANCE AND IMPACT OF THE STUDY: High yields of reuterin may be obtained from selected isolates of Lact. reuteri. Probiotic characteristics of isolates studied in the present work suggest their application in food and feed.

Aldehydes↗
PubMed2003

Stability studies of tablets containing 5 mg of policosanol.

The stability studies of tablets containing 5 mg of policosanol, a new cholesterol lowering drug, were conducted to predict an expiration date and to search the appearance of putative degradation products. All quality parameters such as colour, moisture content, hardness, disintegration, policosanol content and microbiological limits of the tablets were assessed. The effect of extreme treatments such as acid and basic hydrolysis, oxidative and photolytic degradation as well as thermal degradation, on the policosanol content was studied. In addition, studies under extreme conditions of storage [(40 +/- 2) degree C and (75 +/- 5)% R.H.] as well as 37, 45, 55 and 60 degrees C combined with 50, 75 and 92% R.H.) and under ambient conditions of storage for climatic zones II and IV were performed. These studies demonstrate that these tablets are a stable pharmaceutical formulation, without significant changes in their quality criteria at the stressed conditions used, so that policosanol content remains unchanged during the entire studies. The chromatographic profile of the samples after 9 months of thermal degradation shows chromatographic peaks that corresponds to the palmitate and stearate esters of octacosanoyl, triacontanoyl and hexacosanoyl, being the only degradation products observed on these studies.

Anticholesteremic Agents↗
PubMed2002

Mycobacterium fortuitum complex endocarditis-case report and literature review.

Endocarditis due to Mycobacterium fortuitum complex is a rare entity generally linked to the hospital environment. Only 18 cases have been published since 1966. Here we present a case of a female who developed an endocarditis due to Mycobacterium chelonae after valve replacement as well as a review of the literature. The course of this kind of endocarditis is generally subacute and the outcome is usually fatal. Blood cultures were positive in 75% of cases of metallic valve endocarditis, versus 20% in bioprostheses. The treatment must include antibiotics that have shown activity against these mycobacteria, such as amikacin, imipenem, cefoxitin, fluorinated quinolones and macrolides (especially clarithromycin). Surgical removal is recommended. Although the prognosis for the patient is poor, we should expect better outcomes with the use of new antibiotic regimens.

Aortic Valve Insufficiency↗
PubMed2001

Frequency of tuberculous and non-tuberculous mycobacteria in HIV infected patients from Bogota, Colombia.

BACKGROUND: The prevalence of infections by Mycobacterium tuberculosis and non-tuberculous Mycobacterium species in the HIV-infected patient population in Colombia was uncertain despite some pilot studies. We determined the frequency of isolation of Mycobacterium tuberculosis and of non-tuberculous Mycobacterium species in diverse body fluids of HIV-infected patients in Bogota, Colombia. METHODS: Patients who attended the three major HIV/AIDS health care centres in Bogota were prospectively studied over a six month period. A total of 286 patients were enrolled, 20% of them were hospitalized at some point during the study. Sixty four percent (64%) were classified as stage C, 25% as stage B, and 11% as stage A (CDC staging system, 1993). A total of 1,622 clinical samples (mostly paired samples of blood, sputum, stool, and urine) were processed for acid-fast bacilli (AFB) stain and culture. RESULTS: Overall 43 of 1,622 cultures (2.6%) were positive for mycobacteria. Twenty-two sputum samples were positive. Four patients were diagnosed with M. tuberculosis (1.4%). All isolates of M. tuberculosis were sensitive to common anti-tuberculous drugs. M. avium was isolated in thirteen patients (4.5%), but only in three of them the cultures originated from blood. The other isolates were obtained from stool, urine or sputum samples. In three cases, direct AFB smears of blood were positive. Two patients presented simultaneously with M. tuberculosis and M. avium. CONCLUSIONS: Non-tuberculous Mycobacterium infections are frequent in HIV infected patients in Bogota. The diagnostic sensitivity for infection with tuberculous and non-tuberculous mycobacteria can be increased when diverse body fluids are processed from each patient.

Adolescent↗
PubMed2001

Persistence of the insecticide Dimilin 45 ODC on conifer forest foliage in an Atlantic-climate ecosystem.

The oil formulation of diflubenzuron (Dimilin 45 ODC) persisted for 10-12 weeks on the foliage of a conifer forest in an Atlantic-climate ecosystem. Within 22-30 days following treatment, 55-80% of the insecticide had been removed from the foliage. During this period, the concentration of diflubenzuron was higher than 370 ng g(-1). Aerial application at 56.3 g of Al ha(-1) resulted in deposition levels of the insecticide ranging from 867.5 to 1824.4 ng g(-1), depending upon forest characteristics. The results showed that aerial application is only a suitable technique for the treatment of forest areas with dense foliage and/or high tree density and no more than 15% of tree-free area. The only metabolite detected was 2,6-difluorobenzamide, and this persisted on foliage until the first rainfalls occurred. An empirical mathematical correlation was found to express the influence of meteorological variables--rainfall, solar radiation and temperature--on the persistence of the insecticide. These results suggested that degradation of diflubenzuron on foliage could be due to photodegradation. Some recommendations were made to optimize the deposition of the insecticide on foliage and to minimize its persistence and the off-site spray drift.

Diflubenzuron↗
PubMed2001

Hemophilic arthropathy. A scoring system for magnetic resonance imaging.

The aim of this study was to define a system for scoring hemophilic arthropathy (HA) based on MR findings, providing for objective evaluation of the degree of joint involvement and evolution after on-demand administration of FVIII substitutional therapy or prophylactic treatment. A total of 133 MR examinations (89 basal and 44 during follow-up) were performed in 25 patients. Patients were divided in two groups depending on the therapy received and the length of time that the disease had been evolving at the start of the study. Group I was composed of 10 patients with secondary prophylaxis and group II was composed by 15 treated on demand. T1-weighted and T2*-weighted images performed on a 0.5-T unit were prospectively evaluated. The joint involvement was established on a scale of 0 (no abnormalities), I (minimal amount of hemosiderin), II (large amount of hemosiderin and isolated cartilaginous erosion), III (cartilage destruction, bone erosions, and subchondral cysts) to IV (large internal joint derangement, secondary osteoarthritis and/or ankylosis). At basal MR examination, patients of group I showed no abnormalities ( n=28, 75.6%), grade I ( n=3), and grade II ( n=6) of HA. Patients of group II corresponded to MR grades III ( n=21) and IV ( n=11) of HA. The MR follow-up showed improvement in three joints of group I and worsening in 5 joints in group I and 2 joints in group II. Early signs of HA were detected in 10 joints with MR imaging but were underestimated on plain radiographs. Advanced degrees of HA were classified as severe under both imaging techniques. Magnetic resonance is the preferred imaging technique to assess HA. The earliest signs of joint damage, detected by MR, are overlooked by plain radiography. The MR scoring system can be used for evaluating HA. Follow-up MR should be performed to evaluate regression or worsening of the abnormalities, primarily in the case of patients with prophylaxis who usually suffer normal or early joint involvement not detected by other means.

Adult↗