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J Martínez

Publications and source records attributed to J Martínez.

At least 19 recordsLinked to original sources
PubMed2006

Enzymatic analysis of Blomia tropicalis and Blomia kulagini (Acari: Echimyopodidae) allergenic extracts obtained from different phases of culture growth.

The majority of important allergenic extracts from arthropods present enzymatic activity. This activity has been studied particularly in Dermatophagoides house dust mites because of its implication in the stability and immunogenicity of extracts used as tools for the diagnosis and specific treatment of allergic diseases. Extracts from cultures of Blomia tropicalis [van Bronswijk (1973a, b). Acarologia 15:477-489, 490-505] and Blomia kulagini (Zakhvatkin 1936) were used to study enzymatic profiles during three growth periods of the mite population: latency phase, maximum mite concentration during exponential growth, and drop stage. The activities of 19 enzymes were analyzed using the Api Zym system. The results show a large variety of enzymes. Some enzymatic activity was found to be (almost) exclusively attributable to mites. The activity levels of proteases, glycosidases and lipases overlapped with the growth curve. Only phosphatase activity showed no significant change during mite growth when compared with the culture medium. We suggest that the glycosidases (beta-galactosidase, beta-glucuronidase, beta-N-acetylglucosaminidase, alpha-mannosidase and alpha-fucosidase) and proteases (leucine aminopeptidase and trypsin) may constitute suitable parameters for inclusion in the quality control process for the production of allergenic mite extracts, and may help define a new index for conducting environmental controls.

Allergens↗
PubMed2006

Obesity is a definitive risk factor of severity and mortality in acute pancreatitis: an updated meta-analysis.

BACKGROUND/AIMS: Obesity is considered a risk factor in patients with acute pancreatitis. However, the relationship between obesity and mortality in this disease has not been confirmed definitively even in a previous meta-analysis. Since the publication of our previous meta-analysis, one study has been reported about the prognostic value of obesity in acute pancreatitis. We have performed a new meta-analysis to confirm the relationship between obesity and the outcome of acute pancreatitis. DATA SOURCES: A MEDLINE search using 'pancreatitis', 'obesity' and 'body mass index' as search terms. REVIEW METHODS: Clinical studies which investigated the prognostic value of obesity in acute pancreatitis with the following criteria: (a) inclusion of mild and severe acute pancreatitis; (b) use of body mass index (BMI) as the measure of obesity; (c) definition of obesity as BMI >or=30 kg/m(2); (d) definition of severity of acute pancreatitis according to the criteria established in the Atlanta Symposium. Five studies including patients with mild and severe acute pancreatitis and obesity measured by BMI were analyzed. The end points of the meta-analysis were the severity of acute pancreatitis, local complications, systemic complications and mortality. Pooled odds ratio (OR) and confidence intervals (CI) were calculated according to the Mantel-Haenszel method, and heterogeneity was assessed by the multiplicative inverse variance method. RESULTS: Seven hundred and thirty-nine patients were included. There was no heterogeneity for the variables severity, systemic complications, local complications and mortality among the included studies. Severe acute pancreatitis was significantly more frequent in obese patients (OR 2.9, 95% CI 1.8-4.6). Furthermore, those patients developed significantly more systemic (OR 2.3, 95% CI 1.4-3.8) and especially local complications (OR 3.8, 95% CI 2.4-6.6). In this new analysis, mortality was also higher in obese patients (OR 2.1, 95% CI 1.0-4.8). CONCLUSION: Obesity is not only a risk factor for the development of local and systemic complications in acute pancreatitis: it also increases the mortality of this disease.

Acute Disease↗
PubMed2006

Identification of genes involved in imatinib resistance in CML: a gene-expression profiling approach.

The use of the tyrosine kinase inhibitor imatinib, which blocks the enzymatic action of the BCR-ABL fusion protein, has represented a critical advance in chronic myeloid leukemia (CML) treatment. However, a subset of patients initially fails to respond to this treatment. Use of complementary DNA (cDNA) microarray expression profiling allows the identification of genes whose expression is associated with imatinib resistance. Thirty-two CML bone marrow samples, collected before imatinib treatment, were hybridized to a cDNA microarray containing 6500 cancer genes, and analyzed using bootstrap statistics. Patients refractory to interferon-alpha treatment were evaluated for cytogenetic and molecular responses for a minimum of 12 months. A set of 46 genes was differentially expressed in imatinib responders and non-responders. This set includes genes involved in cell adhesion (TNC and SCAM-1), drug metabolism (cyclooxygenase 1), protein tyrosine kinases and phosphatases (BTK and PTPN22). A six-gene prediction model was constructed, which was capable of distinguishing cytogenetic response with an accuracy of 80%. This study identifies a set of genes that may be involved in primary resistance to imatinib, suggesting BCR-ABL-independent mechanisms.

Adolescent↗
PubMed2006

The major allergen of Alternaria alternata (Alt a 1) is expressed in other members of the Pleosporaceae family.

There is general consensus regarding the scarce cross-reactivity existing between Alternaria alternata and other allergenic moulds such as Aspergillus fumigatus, Penicillium notatum or Cladosporium herbarum. However, A. alternata has been shown to have a very significant level of allergenic cross-reactivity with other fungi belonging to the Pleosporaceae family. To date, no biological identity or homologies with other proteins have been described for Alt a 1, and it remains unclear whether the major allergen Alt a 1 contributes to the cross-reactivity shown for these moulds. Specific quantification of Alt a 1 in culture filtrates of Stemphylium botryosum, Ulocladium botrytis, Curvularia lunata, Alternaria tenuissima, C. herbarum, Penicillium chrysogenum and Asp. fumigatus, and immunoblotting using culture filtrate extracts from the above-mentioned moulds and rabbit serum anti-recombinant Alt a 1 have shown significant amounts of Alt a 1 in culture filtrates as well as antigenic components ranging from 14 to 20 kDa that strongly react with the specific serum for all taxonomically related species (Pleosporaceae family). No reactions were revealed in culture filtrates of Cladosporium, Penicillium and Aspergillus. These results restrict the cross-reactivity phenomenon due to Alt a 1 to the scope of the taxonomical term of family.

Allergens↗
PubMed2006

Performance tests of two portable mini gamma cameras for medical applications.

We have developed two prototypes of portable gamma cameras for medical applications based on a previous prototype designed and tested by our group. These cameras use a CsI(Na) continuous scintillation crystal coupled to the new flat-panel-type multianode position-sensitive photomultiplier tube, H8500 from Hamamatsu Photonics. One of the prototypes, mainly intended for intrasurgical use, has a field of view of 44 x 44 mm2, and weighs 1.2 kg. Its intrinsic resolution is better than 1.5 mm and its energy resolution is about 13% at 140 keV. The second prototype, mainly intended for osteological, renal, mammary, and endocrine (thyroid, parathyroid, and suprarenal) scintigraphies, weighs a total of 2 kg. Its average spatial resolution is 2 mm; it has a field of view of 95 x 95 mm2, with an energy resolution of about 15% at 140 keV. The main advantages of these gamma camera prototypes with respect to those previously reported in the literature are high portability and low weight, with no significant loss of sensitivity and spatial resolution. All the electronic components are packed inside the mini gamma cameras, and no external electronic devices are required. The cameras are only connected through the universal serial bus port to a portable PC. In this paper, we present the design of the cameras and describe the procedures that have led us to choose their configuration together with the most important performance features of the cameras. For one of the prototypes, clinical tests on melanoma patients are presented and images are compared with those obtained with a conventional camera.

Breast Neoplasms↗
PubMed2006

Differential uPA expression by TGF-beta1 in gingival fibroblasts.

Transforming Growth Factor-beta1 (TGF-beta1) plays a key role in connective tissue remodeling and inflammation. Under pathological conditions, like periodontal disease, fibroblasts may display an altered response to this growth factor. To investigate this question, we have studied whether TGF-beta1 may differentially regulate the expression of urokinase at the protein level in primary cultures of fibroblasts derived from healthy gingiva, granulation tissue from gingival wounds, and chronic periodontal disease. We observed that TGF-beta1 may repress urokinase expression in healthy gingival fibroblasts and promote its production in granulation-tissue fibroblasts. A significant correlation was found between expression of the myofibroblast marker alpha-smooth-muscle actin and stimulation of urokinase production by TGF-beta1. Immunostaining of gingival wounds showed that myofibroblasts were involved in urokinase production. TGF-beta1-stimulated urokinase expression was blocked after inhibition of the c-jun-NH2 terminal kinase signaling pathway. We propose that stimulation of urokinase production by TGF-beta1 is involved in the responses of activated fibroblasts to tissue injury.

Actins↗
PubMed2006

A comparison of two different dosages of somatostatin combined with sclerotherapy for the treatment of acute esophageal variceal bleeding: a prospective randomized trial.

BACKGROUND: the association of somatostatin (SMT) with endoscopic therapy in patients with cirrhosis and variceal bleeding significantly improves the control of the bleeding episode, and hemodynamic data have shown that a dosage of 500 mg/h allows a more marked reduction of portal pressure versus the usual dosage of 250 mg/h. AIM: to assess if the 500 mg/h dosage is associated with an improved outcome. METHODS: sixty-two patients with variceal bleeding were included in the study. Patients were randomized to receive the usual dosage of SMT (group I: 250 mg/h), or a double dosage (group II: 500 mg/h), together with emergency endoscopic sclerotherapy. RESULTS: the control of the bleeding episode was similar in both groups of patients. Early rebleeding was less frequent in patients receiving double vs. single dosage of SMT (p = 0.06). When considering patients with advanced liver disease (Child-Pugh B or C) early rebleeding was significantly less frequent in patients receiving the 500 mg/h dose of SMT (39 vs. 13%, p = 0.03). CONCLUSIONS: the perfusion of higher doses of SMT (500 mg/h) in association with emergency sclerotherapy in patients with cirrhosis and esophageal hemorrhage significantly decreases the rate of early rebleeding in patients with more advanced stages of liver disease.

Acute Disease↗
PubMed2006

Barnacle allergy: allergen characterization and cross-reactivity with mites.

BACKGROUND: Barnacles are a type of seafood with worldwide distribution and abundant along the shores of temperate seas. They are particularly appreciated and regularly consumed in Portugal as well as in Spain, France and South America, but barnacle allergy is a rare condition of which there is only one reference in the indexed literature. The molecular allergens and possible cross-reactivity phenomena implicated (namely with mites) have not been established. OBJECTIVE: To demonstrate the IgE-mediated allergy to barnacle and to identify the proteins implicated as well as possible cross-reactivity phenomena with mites. METHODS: We report the clinical and laboratory data of five patients with documented IgE-mediated allergy to barnacle. The diagnosis was based on a suggestive clinical history combined with positive skin prick tests (SPT) to barnacle--prick to prick method. Two barnacle extracts were prepared (raw and cooked barnacle) and sodium dodecylsulphate polyacrylamide gel electrophoresis (SDS-PAGE) and IgE-immunoblotting were performed. An immunoblotting inhibition assay with Dermatophagoides pteronyssinus was also done in order to evaluate cross-reactivity. RESULTS: All patients had mite-related asthma and the allergic rhinoconjunctivitis; they all experienced mucocutaneous symptoms. All of them had positive SPT to barnacle, and the immunoblotting showed several allergenic fractions with a wide molecular weight range (19 - 94 kDa). The D. pteronyssinus extract inhibited several IgE-binding protein fractions in the barnacle extract. CONCLUSIONS: We describe five patients with IgE-mediated barnacle allergy. We also describe a group of IgE-binding+proteins between 30 and 75 kDa as the allergenic fractions of this type of Crustacea. Cross-reactivity with D. pteronyssinus was demonstrated in two cases.

Adolescent↗
PubMed2006

Variability of Alt a 1 expression by different strains of Alternaria alternata.

BACKGROUND: While it is well known that there is significant intraspecific variation in the content an potency of Alternaria alternata allergens, little data has been published on intraspecific variability for individual allergens from moulds. OBJECTIVE: To assess the variability of Alt a 1 expression in different strains of A alternata. METHODS: Eleven strains of A alternata were cultured in a Czapek broth medium and culture filtrate extracts were obtained. A sensitive two-site enzyme-linked immunosorbent assay was used to measure Alt a 1 concentrations in medium following 3 weeks of culture and in culture filtrate extracts. RESULTS: Expression of Alt a 1 was highly variable in different strains ofA alternata (coefficient of variation > 135%). A good correlation was found between Alt a 1 concentrations at the beginning of the process and measurements at the end of extract production (r=0.940). CONCLUSIONS: The high variability of Alt a 1 expression in different A alternata strains makes it necessary to measure Alt a 1 concentrations during the first stage of allergenic extract production in order to be able to choose a suitable strain for producing extracts or purifying Alt a 1.

Allergens↗
PubMed2005

Pathological and aetiological studies of multifocal interstitial nephritis in wasted pigs at slaughter.

Multifocal interstitial nephritis in pigs has been associated with several infectious agents. The objective of the present study was to investigate several different potential infectious agents associated with "white-spotted" kidneys in pigs suffering from wasting at slaughter (aged 6-8 months). Twenty-nine case kidneys (with a "white-spotted" gross appearance) classified into 3 macroscopic lesional grades, and 15 control kidneys (lacking gross lesions), were obtained from a pig abattoir. Laboratory analyses to detect potential associations with the aforementioned pathological condition with Leptospira spp., porcine circovirus type 2 (PCV2), porcine parvovirus (PPV), porcine reproductive and respiratory syndrome virus (PRRSV), and bacteria, were carried out. Microscopically, interstitial nephritis with a lymphofollicular inflammatory pattern (follicular nephritis) was observed in both case and control kidneys, with a higher frequency seen in the former ones. No leptospires were identified, although antibodies to the Pomona and Bratislava serovars were detected. Some pyogenic bacteria were also isolated from both case and control kidneys. PCV2 nucleic acid was only detected in 1 case kidney. PRRSV antigen was not found in any tested sample. Some pigs were tested positive for PPV by serology. Apparently, none of the studied agents were specifically associated as being the potential cause of the renal lesions in the studied wasted pigs. The fact that these chronic lesions may have been the consequence of a previous infection with one of these studied microorganisms, or more, and eventually with other non-tested infectious agents during the growing-finishing period, cannot be ruled out.

Abattoirs↗
PubMed2005

Relationship between heat shock protein levels and infectivity in Trichinella spiralis larvae exposed to different stressors.

The aim of the present study was to investigate the relationship between infectivity and the levels of two major heat shock proteins (Hsp70 and Hsp60) in Trichinella spiralis larvae. Parasites were exposed to either sublethal thermal stress (43 and 45 degrees C) or to warm or cold temperature oxidative stress. The stressed larvae were then inoculated into female CD1 mice to determine their infectivity. Hsps were detected and quantified by Western blotting using monoclonal antibodies. Infectivity was expressed as larvae per gram of muscle. Warm temperature oxidative stress (20 mM H2O2 at 37 degrees C) caused a significant increase in Hsp levels and total loss of infectivity. Cold oxidative stress (20 mM H2O2 at 4 degrees C) caused no alterations in either Hsp levels or infectivity. However, high oxidative stress and cold (200 mM H2O2 at 4 degrees C) caused a slight increase in Hsp60 levels and a drastic reduction in infectivity. Exposure of the larvae to 43 or 45 degrees C did not significantly alter Hsp levels or infectivity. These results show that (i) cold reduces the deleterious effects of oxidative stress; (ii) heat induces neither increased Hsp60/Hsp70 levels nor reduces infectivity; (iii) increased Hsp levels induced by oxidative stress may cause lower infectivity.

Animals↗
PubMed2005

Safety of percutaneous ethanol injection as neoadjuvant therapy for hepatocellular carcinoma in waiting list liver transplant candidates.

UNLABELLED: Orthotopic liver transplantation (OLT) as therapy of hepatocellular carcinoma (HCC) improves the survival of a selected group of patients. Unfortunately, the progressive increase in waiting time for OLT may allow tumor progression. Percutaneous ethanol injection (PEI) has been proposed as neoadjuvant therapy for HCC in patients awaiting OLT, but its safety has not been defined. PATIENTS AND METHODS: During a 60-month period, 34 patients (27 men, overall mean age of 58.5 years, range 41-67) with HCC, were listed for OLT. Ultrasonography-guided PEI was delivered into 39 nodules at 117 sessions on an inpatient basis. Written informed consent was obtained from all patients before PEI. Doppler-ultrasonography was done before PEI, immediately after, and 4 weeks later. Noninvasive monitoring of arterial pressure, cardiac rate, and temperature was performed during the procedure and during a 24-hour period after each session. Pain was considered significant if analgesia was required or discontinuation of PEI necessary. Fever was defined as a temperature > or =37.5 degrees C after PEI. RESULTS: Minor complications included pain in 45 sessions (38.5%), fever in 17 (14.5%), arterial hypertension in 14 (12%), hypotension in 7 (7%), and vomiting in 2 (1.7%). The major complications were segmental liver infarction (n = 3), portal branch venous thrombosis (n = 2), ascites (n = 2), and one case each of subcapsular hematoma, duodenal ulcer, pneumonia, hepatic encephalopathy, and hepatic artery thrombosis. In all cases, clinical outcomes were favorable with conservative treatment. No evidence of tumor seeding in the needle track was reported and no PEI-related mortality observed. CONCLUSIONS: PEI is a safe neoadjuvant therapy for HCC on waiting list liver transplant candidates. In our series, pain and self-limited fever were the most frequent complications. Clinically significant severe complications were uncommon, and nonconservative treatments were not required.

Administration, Cutaneous↗
PubMed2005

Prospective interventional study to evaluate the efficacy and safety of liposomal amphotericin B as prophylaxis of fungal infections in high-risk liver transplant recipients.

INTRODUCTION: Invasive fungal infections are a life-threatening complication in transplant recipients. The prevalence of fungal infection after orthotopic liver transplantation (OLT) is 5% to 42%. The most common isolated pathogens are Candida and Aspergillus species. High-risk liver transplant recipients are more susceptible to the development of invasive fungal infections, with prevalence >40% and mortality rates of 78% to 100%. The strategy for fungal prophylaxis in this population has not been defined. PATIENTS AND METHODS: Among 100 consecutive OLT followed for 28 months, 21 recipients (15 men, overall mean age of 48.5 years, range 23-65 years) were considered to be high risk for the development of fungal infections when they presented at least one of the following criteria: acute liver failure, assisted ventilation >7 days, retransplantation, relaparotomy, antibiotic therapy >14 days, transfusion requirements >20 red blood cells units, and/or biliary leakage. This group received intravenous liposomal amphotericin B (1 mg/kg/d for 7-10 days). RESULTS: One-year survival in the high-risk group was 80%. Prevalence of invasive fungal infection was 9.5%. No Candida infection was observed. Two patients developed Aspergillus infection: an abdominal aspergillosis treated with percutaneous drainage and liposomal amphotericin B (5 mg/kg/d) showed a favorable clinical outcome. The other patient who developed brain aspergillosis died 25 days after OLT. Adverse events related to the drug were hypokalemia (n = 2), back pain (n = 3), and renal dysfunction (n = 2). None of these events required withdrawal of the prophylaxis regimen. CONCLUSION: In our series, prophylaxis with liposomal amphotericin B in high-risk liver graft recipients showed a low rate of severe fungal infections. More studies are needed in order to determine the highest risk population and the best drug dosage.

Amphotericin B↗
PubMed2005

Transplantation of CD34+ selected peripheral blood to HLA-identical sibling patients with aplastic anaemia: results from a single institution.

We evaluated the use of CD34+ selected allogeneic peripheral blood as a source of hematopoietic progenitors for allogeneic transplantation in 11 patients with aplastic anemia (AA). The median age was 17 years (range, 6--9), and the median time between diagnosis and transplant 1 month (range, 1--4). Conditioning consisted of cyclophosphamide (50 mg/kg per day) on days--7 to--4 and antithymocyte globulin (30 mg/kg per day) on days--4 to--2 in nine patients. Total lymphoid irradiation was added to the preparative regimen for two. Graft-versus-host disease (GVHD) prophylaxis consisted of cyclosporine A and prednisone. Median doses of CD34+ and CD3+ cells infused were 3.91 x 10(6) and 0.3 x 10(6)/kg, respectively. The median time taken to achieve a neutrophil count >0.5 x 10(9)/l was 12 days and to recover a platelet count >20 x 10(9)/l, 13 days. Two patients developed acute GVHD grade I--II and one developed limited chronic GVHD. There were two treatment-related deaths. At a median follow-up of 44 months (range, 4--3), nine patients were alive with sustained and complete engraftment. This is a promising procedure in patients with AA, resulting in a rapid hematopoietic recovery, a low transplant-related mortality, and a low incidence of GVHD.

Adolescent↗
PubMed2005

Detection and identification of bacterial DNA in serum from patients with acute pancreatitis.

BACKGROUND AND AIMS: Bacterial infections are common complications in patients with acute pancreatitis, and translocation of bacteria from the intestinal lumen is probably the first step in the pathogenesis of these infections. As blood cultures in afebrile patients are usually negative, more sensitive methods to investigate this hypothesis in patients are needed. Our group has recently developed a method to detect the presence of bacterial DNA in biological fluids, and we aimed to detect bacterial DNA in patients with acute pancreatitis, as molecular evidences of bacterial translocation. METHODS: Samples of blood were obtained on three consecutive days within the first six days after admission. Bacterial DNA was detected using a polymerase chain reaction based method, and an automated DNA nucleotide sequencing process allowed identification of bacteria species. RESULTS: Thirty one consecutively admitted patients with acute pancreatitis were studied. Bacterial DNA was detected in six patients (19.3%), and the sequencing process allowed identification of Citrobacter freundii and Pseudomonas aeruginosa. In two patients the same bacteria detected at admission was detected 24 hours later (above 99.9% homology of nucleotide sequence). Basic clinical and biochemical characteristics were similar among patients with or without the presence of bacterial DNA. CONCLUSION: Detection of gram negative bacteria derived bacterial DNA in our series supports the contention that bacterial translocation is a systemic process in approximately 20% of patients with acute pancreatitis that does not seem to be related to the severity of the episode or immediate development of infection.

Acute Disease↗