Search PubMed⌕ Search

Biomedical subjects

J Sastre

Publications and source records attributed to J Sastre.

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

Use of sorption and extraction tests to predict the dynamics of the interaction of trace elements in agricultural soils contaminated by a mine tailing accident.

Over 2000 ha of agricultural soils were contaminated by a pyritic sludge and acidic waste waters coming from a spill from a mining exploitation. The affected soils were acidic with sandy-loam texture (SL), loamy with neutral pH (L), and calcareous, saline, with clay texture (Cs). The Cs soils were contaminated only with acidic waste waters. Sorption and extraction tests were applied to examine the medium-term dynamics of the interaction of trace elements (As, Cd, Cu, Pb and Zn) in the soils. The solid-soil solution distribution coefficient (KD) was determined in soil samples taken 3 months (initial stage, 3M samples) and then nearly 2 years (final stage, 21M samples) after the accident. Distribution coefficient values ranged from the lowest values in the SL samples (from 0.2 l kg(-1) for Cd and Zn to 25 l kg(-1) for As) to higher values in the L and Cs soils. Lead and As had the highest KD in all soils (over 10(5) l kg(-1) in the L soils). No clear dynamics pattern could be derived from these data because of the low heavy metal concentrations in the soil solution. As a complementary approach, four single extractions (0.01 and 1 mol l(-1) CaCl2; 0.05 mol l(-1) EDTA; 0.43 mol l(-1) CH3COOH) were applied to soil and sludge samples. Samples derived from submitting field 3M samples to drying-wetting (DW) cycles were included to define a complete laboratory approach to predict field dynamics. Results from extraction tests indicated that changes of the trace element interaction over time depended on the soil pH and on the source of contamination. For those soils affected only by the acidic waste waters, where an increase in fixation occurred, natural processes such as diffusion controlled dynamics. For those soils contaminated by a mixed source, the dynamics of the interaction was the resultant process of the combination of the natural attenuation and the oxidation of the pyritic sludge. This latter process led to an increase in the remobilization for those elements associated with soluble secondary minerals (Cd and Zn) and to an increase in the fixation for those elements coprecipitating with insoluble secondary minerals (Pb and As). Drying-wetting cycles were useful to predict the dynamics in the field at month-year scale. The CH3COOH was recommended as the best test among those studied here to derive conclusions about dynamics pattern because it provided significant desorption yields in most scenarios. Acidic soils with sludge contamination represented the scenarios with the highest risk, while calcareous soils better attenuated contamination. In a longer time scale, the depletion of calcareous components needs to be controlled.

Journal Article↗
PubMed2004

Phase I/II trial of irinotecan plus high-dose 5-fluorouracil (TTD regimen) as first-line chemotherapy in advanced colorectal cancer.

BACKGROUND: We conducted a phase I/II study of weekly irinotecan [30 min intravenous (i.v.) infusion] combined with 5-fluorouracil (5-FU 3 g/m(2) weekly 48 h i.v. infusion, TTD regimen) as first-line chemotherapy for patients with advanced colorectal cancer (CRC). PATIENTS AND METHODS: The maximum tolerated dose (MTD) and the dose-limiting toxicity (DLT) in the treatment of gastrointestinal solid tumors (in phase I), and the antitumor activity and toxicity of the recommended phase I dose (in phase II) were determined. RESULTS: Diarrhea was the DLT, and irinotecan 80 mg/m(2) plus 5-FU 3 g/m(2) was the recommended phase I dose. In phase II, the confirmed response rate was 44% [95% confidence interval (CI) 29% to 59%] and the median overall survival was 23.8 months. However, grade 3/4 diarrhea affected 59% of patients and led to withdrawal of three patients. A second cohort of patients studied using the same schedule but with a reduced 5-FU starting dose of 2.25 g/m(2) showed improved tolerance (the incidence of grade 4 diarrhea decreased from 28% to 11% and overall grade 3/4 diarrhea to 56%, with no patient withdrawals) but the confirmed response rate was 28% (95% CI 14% to 45%) and median overall survival was 17.2 months. CONCLUSIONS: We found weekly irinotecan 80 mg/m(2) plus TTD regimen (5-FU 2.25 g/m(2) given as 48-h i.v. infusion) to be a feasible and active combined chemotherapy for the first-line treatment of advanced colorectal cancer.

Adult↗
PubMed2004

Pancreatic function after severe acute biliary pancreatitis: the role of necrosectomy.

OBJECTIVES: To investigate the recovery of pancreatic function after severe acute biliary pancreatitis (ABP), especially the influence of necrosectomy on endocrine and exocrine functions. METHODS: Prospective cohort study including 39 patients with severe ABP. According to need or no need for surgical necrosectomy, patients were further subdivided into 2 groups. Functional pancreatic evaluation was carried out 12 months after the ABP episode. Endocrine function was evaluated by an oral glucose tolerance test and exocrine function by fecal fat excretion, fecal chymotrypsin (FQ), and secretin-cerulein tests (SCT). RESULTS: Most of the patients with necrosectomy had an abnormal exocrine pancreatic function, with steatorrhea in 25%. In the group without surgery, exocrine function was pathologic in only 13.3% and there were no cases of steatorrhea. Endocrine function was pathologic in 75% of patients undergoing necrosectomy versus 26.7% in the nonoperated group. In this latter group, the patients with abnormal endocrine function did not require insulin therapy, while in 33.3% of patient in the necrosectomy group insulin was necessary. CONCLUSIONS: In our homogeneous series of severe ABP, necrosectomy impaired significantly pancreatic endocrine and exocrine function. On the other hand, most patients with the same origin and severity index, but without surgical debridement, maintained normal pancreatic function.

Aged↗
PubMed2004

Allergenicity and cross-reactivity of Russian olive pollen (Eleagnus angustifolia).

BACKGROUND: The purposes of this study were: to determine the prevalence of sensitization and immunochemical characterization of Eleagnus angustifolia pollen (Russian olive) that belongs to the family Eleagnaceae. METHODS: A total of 134 patients with rhinoconjunctivitis and/or asthma were studied. Its allergenicity, cross-reactivity with olive pollen and the presence of Ole e 1 and Ole e 4-like molecules were evaluated. RESULTS: Eleagnus angustifolia pollen was detected from May to June. Seventy-three of 134 (30.5%) had positive skin test to E. angustifolia, all of them were positive to olive. There was a good correlation between specific immunoglobulin (Ig)E levels to E. angustifolia and Olea europaea (r = 0.77, P = 0.002). Sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) immunoblots revealed major IgE-binding bands in the E. angustifolia extract of 43 and 63.7 kDa. The E. angustifolia extract was not able to inhibit olive, whereas O. europaea inhibited E. angustifolia up to 41%. The presence of Ole e 1- and Ole e 4-like allergens in E. angustifolia extract was confirmed by enzyme-linked immunosorbent (ELISA) inhibition assays. Nasal challenge with E. angustifolia was positive in three of six patients with positive skin test to both pollens and negative in five patients with positive skin test only to O. europaea. CONCLUSIONS: This study confirms that E. angustifolia is capable of sensitizing individuals in Madrid. A minimal-to-moderate cross-reactivity with olive pollen was established, suggesting some cross-reactivity but not excluding co-sensitization.

Air Pollution↗
PubMed2004

Tolerance and effects on skin reactivity to latex of sublingual rush immunotherapy with a latex extract.

BACKGROUND: Specific immunotherapy could be a therapeutic tool for the increasing problem of sensitisation to Natural Rubber Latex (NRL). OBJECTIVE: To investigate the tolerability of SLIT for Latex and its effects on skin reactivity. METHODS: Twenty-six patients (mean age 35.5 years) with an average history of 7.5 years of cutaneous symptoms plus respiratory symptoms (23/26) due to NRL were studied. All underwent rush sublingual therapy (4 days) with a standardized NRL extract followed by a 9-week maintenance treatment. Local and systemic adverse reactions were monitored throughout the treatment. Skin reactivity to NRL extract was evaluated before, during and at the end of the treatment by latex glove-use test, rubbing test and skin prick test. RESULTS: All patients reached the maintenance dose. Out of 1044 administered doses, 257 (24.6%) produced adverse reactions from which 21.4% were local. Only 10.1% of cases required treatment, mainly with antihistamines alone (5.8%), with 2-agonists alone (0.8%) or associated to antihistamines and/or corticosteroids (2.7%). One patient was precautionary treated twice with adrenaline but completed the treatment without further problems. The glove-use test improved significantly after 5 days and 10 weeks of treatment (p = 0.003, p = 0.0004 respectively), whereas the rubbing test improved significantly only after 10 weeks of treatment. Doctor's assessments confirmed the results obtained with the glove-use test (p = 0.003 after 5 days, and p = 0.004 after 10 weeks) but not those obtained with the rubbing test. No change was detected for SPTs. CONCLUSION: SLIT for NRL allergy is able to modify skin reactivity to NRL in days as assessed with methods reproducing HCWs normal exposure to the allergen. Tolerance of SLIT is better than tolerance reported for injective therapy with NRL, but the build up phase should be administered under medical surveillance until sufficient experience has been accumulated. The long-term effect of the treatment deserves further investigation.

Administration, Sublingual↗
PubMed2003

Egg white proteins as inhalant allergens associated with baker's asthma.

BACKGROUND: Bakery workers may develop IgE-mediated allergy to liquid and aerosolized hen's egg proteins that are commonly used in the baking and confectionery industries. METHODS: We studied four bakery workers who had work-related allergic respiratory symptoms upon exposure to egg aerosols. The causative role of egg proteins in their respiratory symptoms was investigated by immunologic and specific inhalation challenge (SIC) tests. RESULTS: Skin prick tests to egg white extract and to lysozyme gave positives responses in all the subjects, to ovalbumin in two, to ovomucoid in one and to egg yolk in two subjects. They were also sensitized to wheat, rye and barley flours. Specific IgE determinations to egg white were positive in all patients, to lysozyme in two, to ovalbumin in three, to ovomucoid in two and to egg yolk in two of them. Methacholine inhalation tests revealed bronchial hyperresponsiveness in all workers (PC20 < 16 mg/ml). SICs were performed with aqueous extracts of lysozyme (n = 4), ovalbumin (n = 2) and ovomucoid (n = 1), which elicited isolated early asthmatic reactions in all subjects. Double-blind, placebo-controlled, oral challenge tests with raw egg white were positive in three subjects. CONCLUSIONS: These bakery workers had developed IgE-mediated occupational asthma to hen's egg white proteins.

Adult↗
PubMed2003

A further evaluation of the clinical use of specific IgE antibody testing in allergic diseases.

BACKGROUND: The evaluation and interpretation of the results from blood tests measuring specific immunoglobulin E (IgE) antibody concentration is currently made using the dichotomized result from the test despite a quantitative result is obtained. It has been shown that different levels of IgE antibodies, assessed by blood test and skin prick test, may have a relation to presence of symptoms, implying that there is more information in a quantitative result than in the dichotomous--positive or negative. OBJECTIVE: To investigate the clinical utility of quantification of IgE antibodies in the diagnosis of allergic patients and whether such procedure has any advantage to the presently dichotomously used sensitivity and specificity at a fixed cut-off. METHODS: Data from a previously published study (R. Paganelli, I.J. Ansoteugi, J. Sastre, C.-E. Lange, M.H.W.M. Roovers, H. de Groot, N.B. Lindholm, P.W. Ewan, Allergy, 1998; 53) analysing diagnosis of allergic patients in four different clinics were re-evaluated. In the original study consecutive patients with suspected IgE-mediated allergy had been examined and evaluated according to the clinical routine at each clinic, using case history, physical examination, skin tests and laboratory tests, except the test to be evaluated, and given a "doctors' allergen-specific diagnosis" as positive or negative. In the present study the relation between "doctors' allergen-specific diagnosis", expressed as pos/neg, and the quantitative levels of specific IgE antibody concentration was analysed using a logistic regression model. This presentation of results was also compared with the more common characteristics of sensitivity and specificity, and also with Receiver-operator characteristics (ROC) curves. RESULTS: The used logistic model described the relationship between allergen-specific diagnosis in each study and the levels of IgE antibodies. The shape of the curve illustrated the physicians' disposition for a positive diagnose in the study, in relation to the specific IgE antibody level. Differences in the shape of the curve was found both between allergens within clinics and between clinics for the same allergen. No association could be demonstrated between prevalence and shape of the curve. CONCLUSIONS: Conventional sensitivity/specificity figures or ROC concepts only use the qualitative statement of whether IgE is present or not. A risk assessment using the quantitative level of IgE antibody to an allergen increases the utility of the information in clinical context compared with a qualitative statement of whether IgE is present or not. The quantification demonstrated the link between specific IgE antibodies and allergic reactions. The use of objective, well performing quantitative tests should help improve diagnostic accuracy and might provide a way for the patient to understand and manage his or her daily situation and risk for reactions.

Adolescent↗
PubMed2003

Multicenter study evaluating a dual policy of postorchiectomy surveillance and selective adjuvant single-agent carboplatin for patients with clinical stage I seminoma.

BACKGROUND: After decades of irradiation as standard therapy for clinical stage I testicular seminoma, alternative treatment approaches have emerged including postorchiectomy surveillance and adjuvant chemotherapy. This study was performed to assess a dual policy of surveillance and selective single-agent carboplatin (for high-risk cases) in a multicenter setting. PATIENTS AND METHODS: From 1994 to 1999, 203 patients with stage I seminoma were included. Sixty (29.6%) were considered poor-risk cases (i.e. with vascular invasion and/or pathological tumor stage pT2 or greater) and received two courses of adjuvant carboplatin, whereas 143 (70.4%) without risk criteria underwent close surveillance. RESULTS: Median follow-up was 52 months (range 14-92). Relapses were observed in two (3.3%) patients treated with carboplatin and in 23 patients (16.1%) on surveillance, with a median time to recurrence of 11 months (range 3.9-39.6). All relapsing patients were rendered disease-free, mainly with cisplatin-based chemotherapy. Four patients died from tumor-unrelated causes. Actuarial 5-year overall survival was 96.7% and cause-specific survival was 100%. Five-year disease-free survival was 83.5% for patients on surveillance, and 96.6% for those receiving carboplatin. CONCLUSIONS: This dual treatment policy is feasible in a multicenter setting and preserves 70% of patients from adjuvant chemotherapy. Single-agent carboplatin is effective in reducing the relapse rate in patients with high-risk stage I seminoma. A better definition of local risk features would probably improve patient selection, thus minimizing the incidence of recurrences on surveillance.

Adolescent↗
PubMed2003

Pathogenesis of occupational asthma.

The development of occupational asthma (OA) is likely to result from the complex interaction of environmental and host factors. This article addresses a series of issues relating to the multiple environmental factors that could affect the initiation of OA, including the intrinsic characteristics of causative agents, as well as the influence of the level, mode and route of exposure. Although the clinical and pathological features of OA caused by low molecular weight agents resemble those of immunoglobulin (Ig)E-mediated asthma, the failure to detect specific IgE antibodies against most of these agents and/or poor association with disease status have resulted in intense speculation about alternative or complementary physiopathological mechanisms leading to airway sensitisation. In this contribution, the roles of specific immunoglobulin E and G antibodies, cell-mediated immunity and inflammatory effector cells are critically reviewed. Recent advances in the characterisation of the molecular interactions between chemical sensitisers and human airway proteins provide promising avenues for elucidating the immunological basis of occupational asthma caused by low molecular weight agents.

Asthma↗
PubMed2003

Irinotecan (CPT-11) in metastatic colorectal cancer patients resistant to 5-fluorouracil (5-FU): a phase II study.

The efficacy and toxicity of irinotecan (CPT-11) 350 mg/m(2) i.v. once every 3 weeks was assessed in 60 patients with advanced colorectal cancer (CRC) showing failure to 5-fluorouracil (5-FU) treatment. The overall objective response rate was 13.6% (1 complete response and 4 partial responses) and 25 patients (42.4%) showed stable disease; the median time to disease progression was 4.4 months and the median survival was 10.5 months. The main non-hematological toxicities were alopecia (80.3% of patients), diarrhea (75.0%), and nausea/vomiting (71.7%); neutropenia was the main hematological toxicity. Grade 3 or 4 diarrhea appeared in 21 of 131 cycles (16.1%), whereas grade 3 or 4 neutropenia appeared in 78 cycles (25.0%). In conclusion, the present phase II study confirms that CPT-11 350 mg/m(2) every 3 weeks is active and well tolerated as second-line chemotherapy for CRC in 5-FU resistant patients.

Adenocarcinoma↗
PubMed2002

Clinical pattern and therapeutic results achieved in 1490 patients with germ-cell tumours of the testis: the experience of the Spanish Germ-Cell Cancer Group (GG).

OBJECTIVE: To describe the clinical characteristics and treatment results obtained with the application of a homogeneous treatment protocol in 1490 patients with germ-cell tumours (GCT) registered in the 55 hospitals belonging to the Spanish Germ-Cell Cancer Group (GG) during the period between January 1994 and April 2001. METHODS: In general, surveillance was the common policy for stage I patients without local poor prognosis factors, whereas they received adjuvant chemotherapy in case those factor were present. Chemotherapy schedules used in advanced cases were cisplatin and etoposide (EP) for seminoma and BEP or BOMP-EPI in non-seminoma, according to whether the patient was in the good or poor prognosis IGCCCG (International Germ-Cell Cancer Collaborative Group) group. Excision of residual masses was mandatory in non-seminomatous germ-cell tumour (NSGCT). RESULTS: Initial local symptomatology was increased testis size in 90% of cases. Sonography was an excellent diagnostic tool to suggest tumour. Non-seminoma (64.2%) was more frequent than seminoma (35.8%). Approximately 10% had the antecedent of cryptorchidism. Non-seminoma patients were 7 years younger than seminoma. Right testis was involved predominantly. Pre-orchidectomy tumour markers were elevated in 21% of seminoma (betaHGC) and 79% in non-seminoma (alphaFP and/or betaHGC). Scrotum violation occurred in only 1.8%. There were significant differences among stage I and the IGCCCG prognosis groups related to a longer interval between the first symptom and orchiectomy. Eighteen percent of non-seminomatous germ-cell tumour belonged to the poor prognosis IGCCCG group. With a median follow-up to 33 months, this series has achieved a 3 year overall survival of 98% for seminoma and 94% for non-seminoma. Only 10% of excised residual masses present after chemotherapy contained malignant cells. CONCLUSION: Spanish GCT have a similar clinical pattern to that described in the other occidental countries except for a slight increased proportion of non-seminoma upon seminoma. Co-operative groups as GG are unique structures to obtain quick and wide experience on the treatment of testis tumours, contributing to achieve a high cure rate.

Adolescent↗
PubMed2002

Allergenicity and immunochemical characterization of six varieties of Olea europaea.

BACKGROUND: The inhalation of Olea europaea pollen is one of the most important causes of allergic respiratory diseases in the Mediterranean basin. The objective of this study was to investigate the antigenic and allergenic composition of six different O. europaea varieties collected in southern Spain. METHODS: The varieties included in the study were: Acebuche (wild olive), Carrasqueño, Nevado, Hojiblanco, Manzanillo and Picual. Extracts of these six varieties were prepared. Twenty-nine olive individuals with an immunoglobulin(Ig)E-mediated allergy to olive pollen were skin tested with these extracts. The antigenic profile of these extracts was evaluated by SDS-PAGE; the allergenic profile was investigated by immunoblotting using the serum of these 29 individuals. The Ole e 1 content was established by ELISA inhibition using purified Ole e 1 and rabbit polyclonal antibodies and by scanning densitometry. RESULTS: The extracts that induced the smallest wheal size were Acebuche and Hojiblanco, being significantly different from the rest of the extracts. The antigenic and allergenic profiles of the extracts also varied. The Ole e 1 content ranged from 0.050 in Hojiblanco to 0.232 in Manzanillo, measured by ELISA inhibition and from 0.153 in Hojiblanco to 0.677 in Nevado, measured by scanning densitometry. CONCLUSIONS: The different varieties of O. europaea pollen studied demonstrated great differences in the in vivo and in vitro potency of the extracts. There were significant differences in the Ole e 1 content, while the protein content remained very similar in these extracts. This study confirms previous observations of a great variability in the antigenic and allergenic composition of O. europaea pollen extracts and establishes significant differences in Ole e 1 content.

Allergens↗
PubMed2002

Rapid release of Ole e 1 from olive pollen using different solvents.

BACKGROUND: Solubility is an important characteristic of allergenic molecules. The aim of this study was to investigate the solubility of Ole e 1, a major allergen of Olea europaea, using different solvents. MATERIAL AND METHODS: Olea europaea pollen was placed in a glass column and extracted using three different solvents: deionized water, phosphate buffer 0.01 M (PBS) and normal saline (NaCl 0.9%). Several fractions were collected after extraction with each solvent and pooled based on individual protein content. Each fraction corresponded to a different elution profile, as determined by linear regression analysis. After 130 min of extraction, the pollen that remained in the column was further extracted overnight. A control olive pollen extract was also prepared with each solvent. The antigenic and allergenic profiles of all the eluted and pooled fractions were analysed by SDS-PAGE and inmmunoblots. Protein and Ole e 1 content and the amount of protein needed to produce 50% inhibition were also calculated. Ten patients were skin prick tested with the fractions obtained with deionized water. RESULTS: Four elution profiles were obtained using deionized water as the extracting solution and three with the two other solvents. The three solvents produced different kinetics of allergen release. Ole e 1 was rapidly released when water was used, obtaining a total of 256 micro g of Ole e 1/ml after only 7 min of extraction (fraction EC1). Using PBS, or NaCl 0.9%, the release of Ole e 1 started after 4 and 9 min of extraction, respectively. The highest amount ofOle e 1 was eluted after 44 and 26 min, with a total concentration of 162 and 203 micro g of Ole e 1/ml, respectively. The presence of Ole e 1 in each phase was verified by SDS-PAGE and immunoblot analyses. CONCLUSIONS: The extracting solution seems to determine the antigenic profile of olive pollen extracts. Ole e 1 is rapidly released from the pollen grain after extraction in deionized water. The solubility seems to be affected by the use of other solvents. These techniques could be used to manipulate the Ole e 1 content in O. europaea extracts.

Allergens↗
PubMed2002

Capecitabine (Xeloda) in combination with oxaliplatin: a phase I, dose-escalation study in patients with advanced or metastatic solid tumors.

OBJECTIVES: This phase I, dose-escalation study was conducted to determine the recommended dose of intermittent oral capecitabine in combination with a fixed dose of i.v. oxaliplatin. Secondary objectives included evaluation of the safety profile and antitumor activity. PATIENTS AND METHODS: Twenty-three patients with advanced or metastatic solid tumors received a 21-day regimen of oral capecitabine (500, 825, 1000 or 1250 mg/m2 twice daily, days 1-14) in combination with oxaliplatin (130 mg/m2, 2-h i.v. infusion, day 1). Dose-limiting toxicities were determined during the first treatment cycle, and safety and efficacy were evaluated throughout treatment. RESULTS: The recommended dosing schedule is oral capecitabine 1000 mg/m2 twice daily (days 1-14) with i.v. oxaliplatin 130 mg/m2 (day 1) in a 21-day treatment cycle. The principal dose-limiting toxicity was diarrhea. The most frequent treatment-related adverse events occurring during the study were gastrointestinal (nausea/vomiting, diarrhea) and neurological (dysesthesia, paresthesia). The majority of treatment-related adverse events were mild to moderate in intensity, and no grade 4 adverse events occurred in the 15 patients treated at or below the recommended dose. The most common grade 3/4 laboratory abnormalities were lymphocytopenia (52% of patients), thrombocytopenia (22%; grade 3 only), neutropenia (17%) and hyperbilirubinemia (17%). Among patients treated at or below the recommended dose level (n = 15), only two patients experienced grade 3 neutropenia and no patients experienced grade 4 neutropenia. Partial tumor responses occurred in six patients (26%), including five of nine patients (55%) with colorectal cancer. All responding patients were pretreated with 5-fluorouracil and four responders had received prior irinotecan. CONCLUSIONS: Oral capecitabine with i.v. oxaliplatin is a feasible combination regimen that shows promising antitumor activity in patients with colorectal cancer. There is an ongoing, phase II study to further characterize the safety and efficacy of this combination as first-line therapy for metastatic colorectal cancer, using the recommended dose identified in this study.

Administration, Oral↗