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R Rodriguez

Publications and source records attributed to R Rodriguez.

At least 91 records · Page 5Linked to original sources
PubMed2000

A sensitive monoclonal antibody sandwich ELISA for the measurement of the major olive pollen allergen Ole e 1.

BACKGROUND: Olive pollen is a major cause of inhalant allergy in countries around the Mediterranean sea. The major allergen of olive pollen is Ole e 1. Measurement of the major allergen content of allergen products for diagnosis and therapy is becoming an essential element of standardization protocols. This study aimed at the development of a monoclonal antibody (mAb) sandwich ELISA for Ole e 1. METHODS: Balb/c mice immunized with Ole e 1 were used for the production of mAbs. Screening of mice and hybridomas was performed in a RIA with radiolabeled purified Ole e 1. Purified mAbs were used as catching and/or (biotinylated) detecting antibodies in sandwich ELISA. RESULTS: Four mAbs (IgG1kappa) directed to nonoverlapping epitopes on Ole e 1 were obtained: 1A12, 5C1, 10A12 and 3H8. Both 1A12 and 10A12 were successfully used for affinity purification of Ole e 1 from olive pollen extract. Two sandwich ELISAs were developed, with 1A12 and 10A12 as catching, and 5C1 and 3H8 as detecting antibodies, respectively. Both catching and detecting antibodies were used in similar concentrations, ranging from 60 to 100 ng/well. For both ELISAs, the sensitivity was approximately 1 ng/ml of Ole e 1. The measuring range was from 1 to 25 ng/ml. No significant differences were observed, when the performance of both ELISAs in standardization of olive pollen extracts was compared. CONCLUSIONS: Two sensitive sandwich ELISAs for the major olive pollen allergen Ole e 1 were developed. They will prove to be useful tools in allergen standardization protocols.

Allergens↗
PubMed2000

Ability of the 1992 and 1997 American Joint Committee on Cancer staging systems for prostate cancer to predict progression-free survival after radical prostatectomy for stage T2 disease.

PURPOSE: In a revised 1997 edition the American Joint Committee on Cancer (AJCC) staging for prostate cancer reduced the subdivision of T2 disease from 3 (T2a, T2b and T2c) to 2 substages by combining single lobe disease (T2a and T2b) into a single stage, now termed T2a. We retrospectively reviewed a large series of men with clinically organ confined prostate cancer who underwent surgery by a single surgeon to determine how this change affected the ability of the staging system to predict outcome. MATERIALS AND METHODS: Of 2, 293 cases treated with radical prostatectomy from 1982 to 1998, 1, 314 were clinically staged to have T2 disease. We analyzed the freedom from biochemical prostate specific antigen (PSA) progression after radical prostatectomy according to the 1992 and 1997 AJCC staging criteria. RESULTS: Overall the actuarial 5 and 10-year biochemical progression-free survival rates for the whole group were 82% and 71%, respectively. The actuarial recurrence-free rate was significantly different for patients with 1992 AJCC T2a (T2a92) versus T2b (T2b92) disease (p <0.0001) but similar for those with 1992 T2b versus T2c (T2c92) disease (p = 0.1165). The actuarial recurrence-free rate was significantly different for patients with 1997 AJCC T2a (T2a97) versus T2b (T2b97) disease (p = 0.0001). However, the overall recurrence-free rate was lower in the T2a97 group compared with the T2a92 group. CONCLUSIONS: The 1992 AJCC staging of T2 prostate cancer yielded a significant difference in the outcome of patients with single lobe disease (T2a92 and T2b92), which is obscured by the 1997 staging criteria. Therefore, we believe that the next revision of the AJCC staging system should revert back to the 1992 AJCC system of subdividing a single lobe disease category into T2a and T2b. Alternatively the committee may want to merge T2b92 and T2c92 stages into a new staging entity, since there was no statistical difference in the outcome of these 2 groups.

Adult↗
PubMed2000

Biological pathways to bladder carcinogenesis.

The transformation of normal urothelium into histologically different neoplastic states has been well characterized, and current clinical management of both superficial and invasive bladder cancer has benefited from recent scientific discoveries. The ability to define novel treatment strategies including surgical, chemotherapeutic, and gene therapies relies on our understanding of the basic mechanisms underlying human bladder carcinogenesis. Many in vitro culture systems and in vivo animal models have been developed over recent years, which have been used to define key molecular events that are associated with the development of bladder cancer. The biological pathways through which normal urothelium may progress to superficial or invasive disease will be discussed in the framework of recent advances in the field.

Animals↗
PubMed1999

Preclinical evaluation of a synthetic Plasmodium falciparum MAP malaria vaccine in Aotus monkeys and mice.

Multiple antigen peptides (MAPs) containing epitopes of the major surface protein of the malaria sporozoite, the circumsporozoite (CS) protein, have been shown in previous studies to elicit antibody-mediated protection against sporozoite challenge in experimental murine and simian hosts. For the preparation for a phase I trial of a P. falciparum (T1B)4 MAP, which contains T and B cell epitopes from the CS repeat region, pre-clinical immunogenicity and adjuvant formulation studies were carried out in mice and Aotus monkeys. The (T1B)4 MAP was found to be immunogenic in three different species of owl monkeys, Aotus nancymae, A. vociferans and A. nigriceps. Optimal antibody responses were obtained in A. nancymae immunized s.c. with (T1B)4 MAP emulsified in Freund's, in which peak titers of over 10(6) were obtained in individual monkeys. MAP immunized A. vociferans also developed high levels of anti-sporozoite antibodies, although the kinetics and the magnitude of the response differed from A. nancymae. (T1B)4 MAP adsorbed to alum (aluminum hydroxide), a formulation that is acceptable for human use, was less immunogenic in naive A. nancymae, as well as A. nigriceps. The injection of MAPs/alum, however, significantly enhanced antibody responses in sporozoite-primed monkeys, suggesting that the administration of the MAP vaccine may be an effective means to increase the low levels of antibody present in individuals living in malaria endemic areas. The addition of a co-adjuvant QS-21, a purified saponin, significantly increased the immunogenicity of the alum-adsorbed MAP in both mice and monkeys, providing a vaccine formulation suitable for phase I trials in human volunteers.

Alum Compounds↗
PubMed1999

Antiviral therapy for HIV patients with renal insufficiency.

Patients with HIV infection and HIV-related opportunistic infections are treated extensively with a spectrum of drugs. Introduction of new antiretroviral drugs, such as protease inhibitors and nonnucleoside reverse transcriptase inhibitors in addition to nucleoside reverse transcriptase inhibitors, has created exciting dimensions in treatment strategies. Renal dysfunction is also common in HIV-infected patients. Because some drugs used in HIV are primarily excreted unchanged by the kidney, dose adjustments are necessary in patients with renal insufficiency. Drugs such as foscarnet, cidofovir and adefovir are directly nephrotoxic, whereas acyclovir can crystallize in the kidneys, and indinavir may cause nephrolithiasis. This paper reviews the impact of renal insufficiency on pharmacokinetics of antiviral drugs used in HIV disease and discusses dosage recommendations needed to avoid toxicity. Finally, we summarize the effects of dialysis on removal of these drugs.

AIDS-Related Opportunistic Infections↗
PubMed1999

Sequence and diversity of T-cell receptor beta-chain V and J genes of the owl monkey Aotus nancymaae.

The New World primate Aotus nancymaae is susceptible to infection with the human malaria parasite Plasmodium falciparum and has therefore been recommended by the World Health Organization as a model for the evaluation of malaria vaccine candidates. Recently, we have shown that Aotus TCRVA genes and TCRJA segments exhibit a high degree of similarity to human counterparts. In the present report we used reverse transcription polymerase chain reaction to analyze the sequences of A. nancymaae TCR beta-chain gene rearrangements. Alignment with human sequences and phylogenetic comparison identified 18 distinct Aotus TCRBV genes homologous to the human TCRBV gene families 2, 4, 5, 6, 7, 9, 12, 15, 24, and 28. Multiple Aotus genes were found in the TCRBV4, 5, 6, and 7 families. Some of these TCRBV genes aligned best to the same human gene and thus do not seem to have separate human homologues. Amino acid sequences of the Aotus TCRBV genes were 77 to 90% identical to their closest human counterparts. Ten distinct Aotus TCRBJ segments homologous to the human segments J1-1, J1-2, J1-4, J1-5, J1-6, J2-1, J2-2, J2-3, J2-4, J2-5 were found. In some cases the amino acid sequences of Aotus and human TCRBJ segments were completely identical. A comparison of the proportion of synonymous and non-synonymous substitutions in Aotus vs human beta-chain-encoding genes revealed a dominance of synonymous substitutions in TCRBJ segments and of nonsynonymous substitutions in TCRBV segments. Dominance of nonsynonymous substitutions was more pronounced in TCRBV CDR1 and CDR2 regions than in the framework regions. No evidence for the emergence of new TCRBJ segments or TCRBV families was found. These results confirm that the TCR repertoire in primates is remarkably stable and support the concept of using Aotus monkeys as an infection model for the evaluation of future subunit vaccine candidates.

Amino Acid Sequence↗
PubMed1999

The spatial properties of a model neuron increase its coding range.

The coding properties of one-compartment and two-compartment model neurons are compared. The membrane depolarization in both models is described as a deterministic leaky integrator. Interspike intervals are identified with the periods between reset of the depolarization after firing and consecutive crossing of a fixed firing threshold. The two-point model has an input in the dendritic compartment and an output in the trigger-zone compartment. it is shown that the sensitivity threshold for the two-point model is shifted to the larger values of the input intensity with respect to the sensitivity threshold of its single-point counterpart. Further, its coding range is substantially larger than the coding range of the single-point model.

Models, Neurological↗
PubMed1999

Detection of adenocarcinoma by urinary microsatellite analysis after augmentation cystoplasty.

Augmentation cystoplasty is associated with an increased risk of bladder cancer development between 10 and 20 years after augmentation. Using microsatellite analysis, we analyzed urine obtained before surgical resection of the malignant lesion from a patient who developed invasive adenocarcinoma after augmentation cystoplasty. Loss of heterozygosity was identified in both urine and tumor samples from this patient. This observation suggests that microsatellite urine analysis may be useful as a monitoring tool for patients after augmentation cystoplasty.

Adenocarcinoma↗
PubMed1999

Association of HLA shared epitope with joint damage progression in rheumatoid arthritis.

A nine years prospective study was performed on 82 Spanish rheumatoid arthritis patients with a disease duration of less than two years at the study entry, in order to evaluate the role of HLA markers in the susceptibility and progression of rheumatoid arthritis. Radiological evaluation of disease severity was performed at the time of diagnosis and 9 years later. High resolution HLA-DR typing demonstrated that the presence of the shared epitope (SE) was more frequent among patients (61% vs. 31% in controls; p = 0.00003; OR = 3.48). Fourteen patients carried two SE+ HLA-DRB1 alleles (SE+/+); 36, one single allele (SE+/-) and 32 were SE negative (SE-/-). HLA-DR4 (particularly DRB1*0401 and DRB 1*0405) and HLA-DR10 were increased among patients. At study entry, the frequencies of locally severe (hands and feet) RA were more frequent among SE+/+ patients (79%) than among SE+/- (47%) and SE-/-(44%) patients (p = 0.05; RR = 1.80). After 9 years of disease these differences disappeared, whereas differences in the extent of the disease arise: 79%, 50% and 32% of SE+/+, SE+/- and SE-/- patients respectively showed large joints involvement (shoulders, elbows, hips and knees) (p = 0.01; RR = 2.44 for SE+/+ vs. SE-/-; and p = 0.04; RR = 1.81 for SE+ vs. SE-). These results suggest that the presence of the shared epitope is associated with the extent and progression of radiological joint damage in rheumatoid arthritis.

Adult↗
PubMed1999

Complex associations between HLA-DRB1 genes and female rheumatoid arthritis: results from a prospective study.

We followed 138 Spanish patients (37 men and 101 women) with rheumatoid arthritis (RA) to analyze whether patient sex influenced the HLA-DRB1 associations with disease susceptibility. Results showed that, although a high increase of the shared epitope (SE) was observed in both genders, distribution of HLA-DRB1 specificities differs from males to females: DR1 was increased among male patients, whereas DR4 as well as DR10 were preferentially associated with female RA. To further explore whether this phenomenon operates either on susceptibility or on disease progression, 82 patients (25 males and 57 females) among the whole group were followed during the first 8 to 10 years of their disease. Results from this prospective study showed that the association of the SE with radiological disease severity was found in both male and female patients, although it was stronger among the latter group. Interestingly, DR1- as well as DR4-related alleles contributed to the high frequency of SE among female patients with early small-joints severe RA and/or long-term large-joint erosions. These results suggest that HLA polymorphism might be involved in RA pathogenesis through two mechanisms: (a) in combination with patient sex, operating in disease induction; and (b) independent of patient sex, influencing disease severity and progression.

Arthritis, Rheumatoid↗
PubMed1999

CTLA4 polymorphisms in Spanish patients with rheumatoid arthritis.

Cytotoxic T-lymphocyte antigen 4 (CTLA4) polymorphisms located in the promotor region at positions -318 (C/T) and in exon 1 (49 A/ G) were investigated in 138 Spanish patients (37 men and 101 women) with rheumatoid arthritis and in 305 ethnically-matched healthy controls. When the allelic and genotypic frequencies corresponding to the CTLA4 -318 position were compared, no significant differences between patients and controls were found. However, when the CTLA4 49 A/G polymorphism was analysed, a significant increase of A/G heterozygous individuals among female patients (48.5% vs. 33.8% in controls; P=0.008; OR=2.0) was observed. This increase was absent among males (37.8%, P=NS). Analysis of the CTLA4 49 polymorphism with respect to HLA-DRB1 typing demonstrated a significant increase of A/G heterozygosity in the HLA-DR3-positive patient group compared with HLA-DR3-negative patient group (14/19, 74% vs. 49/119, 41%; P=0.009, OR=4.0). The increase of A/G genotype among HLA-DR3-positive patients was found in both males (4/6, 67%) and females' (10/13, 77%), although statistical differences were only reached in the female group. These results provide new insight into this complex association, confirm previous data from other studies, and suggest that the CTLA4 gene could be involved in the pathogenesis of rheumatoid arthritis.

Abatacept↗