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Biomedical subjects

J Oliva

Publications and source records attributed to J Oliva.

At least 19 recordsLinked to original sources
PubMed2005

Effects of clarification and filtration processes on the removal of fungicide residues in red wines (var. Monastrell).

The effects of six clarification agents (egg albumin, blood albumin, bentonite plus gelatin, charcoal, PVPP, and silica gel) on the removal of residues of four fungicides (cyprodinil, fludioxonil, pyrimethanil, and quinoxyfen) applied directly to a racked red wine, elaborated from Monastrell variety grapes from the D.O. region of Jumilla (Murcia, Spain), are studied. The clarified wines were filtered with 0.45 microm nylon filters to determine the influence of this winemaking process in the disappearance of fungicide residues. Analytical determination of cyprodinil, fludioxonil and pyrimethanil was performed by gas chromatography with an alkaline thermoionic detector (NPD), whereas that of quinoxyfen using an electron captor detector (ECD). In general, and for all of the fungicides except quinoxyfen, blood albumin has proved to be the most effective clarifying agent in the removal of residues, whereas silica gel proved to be ineffective against all of the pesticides with the exception of fludioxonil. Quinoxyfen is the least persistent fungicide in the clarified wines and that which appears with highest frequency in the lees. In general, filtration is not an effective step in the elimination of wine residues. The greatest elimination after filtration is obtained in wines clarified with charcoal and the lowest in those clarified with PVPP.

Charcoal↗
PubMed2005

Fungicide dissipation curves in winemaking processes with and without maceration step.

The evolution of residual levels of four fungicides (cyprodinil, fludioxonil, pyrimethanil, and quinoxyfen) during the elaboration of three types of wine with maceration (traditional red wine, carbonic maceration red wine, and red wine of long maceration and prefermentation at low temperature) and two types of wine without maceration (rose and white) has been studied. The disappearance curves of each fungicide have been analyzed during the period of each winemaking process (21 days) and during the different enological steps involved in the elaborations. The residual levels of fludioxonil reduce most quickly during the winemaking processes without maceration, whereas the decrease in levels of pyrimethanil was the slowest in practically all cases (with and without maceration). During carbonic maceration winemaking, the decay constant of cyprodinil was greater than that of the other pesticides in all assays (time and steps).

Food Handling↗
PubMed2005

Small cell sweat gland carcinoma of childhood.

Small cell sweat gland carcinoma appears to represent a very unusual histological type of sweat gland anlage tumour presenting in children. The differential diagnosis from other small blue cell tumours involving the skin is often difficult. The present report confirms the original observation describing two patients of 2 and 5 years of age harbouring cutaneous tumours. The histology of these lesions showed a monomorphic proliferation of small cells with a high mitotic rate and areas of necrosis. Immunohistochemically, the cells were negative for desmin, cytokeratin 7, cytokeratin 20, Cam 5.2, CD99, chromogranin, CD56, synaptophysin, and S-100, and focally positive for the pancytokeratin marker AE1/AE3, carcinoembryonic antigen (one case), and neurone specific enolase (one case). The prognosis of this type of tumour seems to be good. As more cases are added, the clinical pathological spectrum of the lesion will become better defined.

Biomarkers, Tumor↗
PubMed2004

HCH and DDT residues in human placentas in Murcia (Spain).

Organochlorinated insecticides are ubiquitous toxicants that are transplacentally transferred from mother to fetus and are reported to produce adverse health effects in pregnant woman and neonates. To investigate hexachlorocyclohexane (HCH) and 1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane (DDT) exposure in pregnant woman, a total of 102 placentas were analyzed by a gas chromatograph equipped with electron capture detector. Organochlorine residues were found in 69.6% of the samples. Lindane was detected in 24.5%, alpha-HCH in 2.9%, beta-HCH in 6.9%, p,p'-DDE in 44.1%, p,p'-DDT in 14.7% and p,p'-DDD in 10.8% of the samples. The pattern of dispersal by these substances in Murcia is similar to that described by different authors in other countries. Therefore, the past use of DDT and the present employment of lindane seem to be reflected in body tissues of the residents of this area.

Adult↗
PubMed2001

Predicting tuberculosis among HIV-infected patients admitted to hospital: comparison of a model with clinical judgment of infectious disease specialists.

The aim of this prospective study was to compare a model based on clinical variables with the clinical judgment of infectious disease specialists to identify HIV-infected patients requiring isolation at admission in order to prevent the nosocomial transmission of tuberculosis. Clinical, epidemiological and radiological variables available at admission were recorded for 362 admissions of 274 HIV-infected patients. Using multiple logistic regression analysis, a model to identify patients with tuberculosis was developed based on four clinical variables (node enlargement, constitutional symptoms, intravenous drug use, history of previous correct therapy for tuberculosis) and a positive auramine sputum stain. This model was applied to each of the 362 admissions studied. The decision made by the infectious disease specialist at admission was also recorded. The results indicate that application of the model would have allowed physicians to correctly identify and isolate 24 of 27 patients with tuberculosis, while 5.4 patients without tuberculosis would have been unnecessarily isolated for every patient with tuberculosis. The results for the infectious disease specialists were slightly better, with 26 of 27 patients with tuberculosis being identified and isolated correctly and only 3.2 patients being isolated unnecessarily for every patient with tuberculosis. Thus, a simple model based on clinical variables may be useful in helping physicians identify tuberculosis carriers among HIV-infected patients, but infectious disease specialists are able to identify them more efficiently.

AIDS-Related Opportunistic Infections↗
PubMed2001

Risk factors for nosocomial transmission of multidrug-resistant tuberculosis due to Mycobacterium bovis among HIV-infected patients.

OBJECTIVE: To identify risk factors for transmission of multidrug-resistant tuberculosis (MDR-TB) among hospitalized human immunodeficiency virus (HIV) infected patients exposed during a nosocomial outbreak. DESIGN: Case control study. Cases were HIV-infected patients with MDR-TB due to Mycobacterium bovis (MDR-TBMb) who acquired the disease after exposure to an MDR-TBMb patient in an hospital ward. Controls were HIV-infected patients exposed to a case of MDR-TBMb in an hospital ward but who did not develop MDR-TBMb during the follow-up. RESULTS: Nineteen cases and 31 controls were included. CD4 cell counts were significantly lower among cases. Exposure in the infectious diseases ward or exposure to the index patient were associated with development of MDR-TBMb, while exposure during a single-room hospital stay and exposure in the respiratory isolation ward were associated with non-development of MDR-TBMb. A multiple regression logistic model showed that only a CD4 cell count below 50/microL and exposure to the index patient increased the risk of developing MDR-TBMb (P < 0.05). Hospitalization in a single room seemed to protect HIV-infected patients from developing nosocomial MDR-TBMb (P = 0.052). CONCLUSIONS: Over classic risk factors, such as length of exposure or sharing a room with a case, severe immunosuppression independently increases the risk of MDR-TB transmission in the context of a nosocomial MDR-TB outbreak among HIV-infected patients. This information must be considered in the management of tuberculosis outbreaks. Patients with CD4 cell counts below 50/microL should be the principal group targeted for prevention strategies in nosocomial outbreaks.

Adult↗
PubMed2000

Multiresidue method for the rapid determination of organophosphorus insecticides in grapes, must and wine.

A rapid multiresidue gas chromatographic method for determining 12 insecticides in grapes, must and wine is described. A simple on-line microextraction method for isolating frequently applied insecticides on vineyard is used. The matrix, once extracted with an acetone-dichloromethane (1:1, v/v) mixture, was filtered and concentrated. Nitrogen-phosphorus detection (NPD) and electron-capture detection (ECD) were used to identify and quantify the insecticides, the findings being confirmed using mass spectrometric detection (MSD). No clean-up was necessary for either NPD or ECD. The regression coefficients relating to linearity were at least 0.99. Recoveries from spiked grape, must and wine samples ranged from 80 to 108% and relative standard deviations were no higher than 16% in the most unfavourable case. Individual detection limits were in the range 0.02-0.1 ng. Limits of quantification varied from 0.01 to 0.05 mg kg(-1), which are below the maximum residue limits set by the legislation of the main wine-producing countries of the European Union. Only in the case of methidathion and quinalphos were the limits of quantification equivalent to the maximum residue limits (0.05 mg kg(-1)) established by Spanish and French legislation, respectively.

Insecticides↗
PubMed2000

Multiresidue method for the rapid determination--in grape, must and wine--of fungicides frequently used on vineyards.

A rapid multiresidue gas chromatographic method for determining 17 fungicides in grapes, must and wine, widely used on vineyards, is described. A simple on-line microextraction method for isolation of fungicides was used. Nitrogen-phosphorus and electron-capture detection were used for the identification and quantitation of pesticides. For confirmation, mass spectrometic detection was used. Because of the high selectivity of both detection methods, no clean-up was necessary. The regression coefficients relating to linearity were at least 0.994. Recoveries from spiked grapes, must and wine samples ranged from 78 to 107% and relative standard deviations were not higher than 14%. Individual detection limits were in the range 0.02-0.1 ng. Limits of quantification varied from 0.01 to 0.05 mg/kg, smaller in all cases than the maximum residue limits set down by the legislations of Spain, France and Italy, the main wine-producing countries of the European Union. Only for fludioxonil and hexaconazole do the limits of quantification coincide with the maximum residue limits (0.05 mg/kg) established by the Spanish legislation.

Chromatography, Gas↗
PubMed2000

Evolution of chlorpyrifos, fenarimol, metalaxyl, penconazole, and vinclozolin in red wines elaborated by carbonic maceration of Monastrell grapes.

The influence of the different steps involved in the wine-making process on the disappearance of chlorpyrifos, fenarimol, metalaxyl, penconazole, and vinclozolin in red wines elaborated by carbonic maceration of Monastrell grapes was studied. The initial levels of the residues in grapes ranged from 0.28 mg/kg (penconazole) to 1 mg/kg (chlorpyrifos). Ten days after the beginning of maceration, the compound that had decreased least was chlorpyrifos (83% of initial value remaining), whereas metalaxyl, the least persistent of the residues, had decreased to 49% of its initial value. In the free-run juice, on the other hand, the highest percentage remaining corresponded to metalaxyl (10%) and the lowest to chlorpyrifos (0. 1%). After pressing, the percentages of initial values eliminated in pomace varied from 82.7% for chlorpyrifos to 17.7% for metalaxyl, whereas in the press juice the opposite was the case (37% metalaxyl and 2% chlorpyrifos remaining). In finished wine, there were residues of all the pesticides, with the exception of chlorpyrifos, metalaxyl (21%) being the most persistent. The percentages eliminated in the lees varied from 1.5 to 2.5% of the initial value.

Carbonic Acid↗
PubMed2000

Antibodies against the COOH-terminal region of E. coli ClpP protease in patients with primary biliary cirrhosis.

BACKGROUND/AIMS: The presence of antibodies in sera from patients with autoimmune diseases is an important tool for diagnosis and for providing insights into the mechanisms leading to autoimmunity. The aim of this study was to characterize new reactive antigens in liver autoimmune diseases. METHODS: Sera of patients with liver-related autoimmune (n=74) and non-liver-related autoimmune (n= 211) diseases, non-autoimmune liver diseases (n=18) and healthy controls (n=160) were evaluated for antibodies against E. coli ClpP protease (EClpP) and 20S proteasome by immunoblot analysis. RESULTS: Antibodies against EClpP were detected in 15 of 50 patients with primary biliary cirrhosis, in only one of 100 patients with systemic lupus erythematosus, and in three healthy subjects (Chi-square 59.1, d.f. 2, p< 0.001). Antibodies to 20S proteasome were found in only 35 of 100 patients with systemic lupus erythematosus. All other sera from patients with autoimmune diseases, liver diseases other than primary biliary cirrhosis, and healthy controls were negative for both antigens. Both IgG and IgM classes of antibodies against EClpP were present in primary biliary cirrhosis patient sera with titers of 1/400-1/1000. By using recombinant techniques and peptide ELISA, the immunodominant EClpP epitope recognized by the sera from primary biliary cirrhosis patients was localized in the amino acid sequences 177-194 (QIERDTERDRFLSAPEAV) within the COOH-terminal of EClpP. Affinity-purification of these anti-EClpP antibodies and immunoabsorption experiments established that the antibodies are specific for the bacterial EClpP. CONCLUSIONS: Bacterial ECIpP has been identified as a new antigen specifically reacting with sera from approximately one third of patients with primary biliary cirrhosis.

Adenosine Triphosphatases↗
PubMed1999

Mitochondrial localization and oligomeric structure of HClpP, the human homologue of E. coli ClpP.

A bacterially expressed recombinant HClpP protein, the human homologue of Escherichia coli ClpP protease, was used to obtain specific polyclonal antibodies. Those antibodies identify a 26 kDa polypeptide in mitochondrial subcellular fractions of rat and human liver. Immunofluorescence and electron microscopic studies demonstrate that the mammalian homologue of ClpP is located in the mitochondrial matrix with a tendency to be found in association with the inner mitochondrial membrane. An HClpP recombinant protein with a truncated NH2terminus (missing the first 58 amino acid residues) shows a molecular mass of 26 kDa under denaturing conditions. This N-truncated HClpP recombinant protein shows a native molecular mass of 340 kDa that is identical with the native molecular mass of the partially purified protein from rat liver mitochondria. Electron microscopy shows that the N-truncated recombinant HClpP has a ring shape with seven identical morphological units in the periphery, exhibiting a 7-fold symmetry. The native molecular mass and the electron microscopic studies suggest that mitochondrial ClpP is composed of two heptameric rings with 7-fold symmetry, similar to E. coli ClpP.

Adenosine Triphosphatases↗
PubMed1999

Determination of chlorpyrifos, penconazole, fenarimol, vinclozolin and metalaxyl in grapes, must and wine by on-line microextraction and gas chromatography.

A rapid gas chromatographic method for determination of residue levels of one insecticide (chlorpyrifos) and four fungicides (penconazole, fenarimol, vinclozolin and metalaxyl) in grapes, must and wine is described. An on-line microextraction method was used. The matrix, once extracted with a mixture of acetone-dichloromethane (1:1, v/v) was filtered and concentrated. Electron-capture detection for chlorpyrifos, penconazole, fenarimol and vinclozolin and mass-selective detection in the selected-ion monitoring mode for metalaxyl were utilised. No clean-up was necessary because there were no interferences in the area of interest of the chromatogram. Linearity of both detectors, in the range 0.02-2 ng/microliter, was checked. In all cases, the correlation coefficient was the same or superior to 0.997. Recoveries from spiked grapes, must and wine ranged from 78% to 101% (fortification level, 0.1-1 mg/kg). Limits of determination were between 0.01 mg/kg for metalaxyl and 0.001 mg/kg for vinclozolin.

Alanine↗
PubMed1999

Evolution of residual levels of six pesticides during elaboration of red wines. Effect of wine-making procedures in their dissappearance.

The effect of wine-making procedures on the concentrations of six pesticides (chlorpyrifos, penconazole, fenarimol, vinclozolin, metalaxyl, and mancozeb) in red wines has been studied. During maceration stage (4 days), the percentage remaining of chlorpyrifos, penconazole, and metalaxyl was approximately 90%, whereas that of fenarimol, vinclozolin, and mancozeb is somewhat smaller (74-67%). The residual levels found in pressed must were </=20%, except for metalaxyl (69%). From the whole concentration of chlorpyrifos in must, 85% is eliminated from the racking step; clarification (bentonite plus gelatin) eliminates 43% of the product found in the decanted wine, and with filtration, all of the residue is eliminated. Penconazole and mancozeb are retained on the lees in proportions of 43 and 31%, respectively. The eliminated percentage of vinclozolin after racking is 29%, whereas clarification and filtration reduce its proportion in the wine to 33 and 28%, respectively. Finally, fenarimol and metalaxyl are eliminated in smaller proportion with the realization of these processes.

Pesticide Residues↗
PubMed1999

Effect of pesticide residues on the aromatic composition of red wines.

The influence of pesticide residues on the aromatic composition (major and minor volatiles) of red wines made from Vitis vinifera (Monastrell var.) was studied by comparing the concentration of aromas in wines made from grapes subjected (or not) to phytosanitary treatment with chlorpyrifos, fenarimol, mancozeb, metalaxyl, penconazole, and vinclozolin, according to the agricultural practice of the area. The analytical determination of the major volatiles was made by gas chromatography using a flame ionization detector, while the minor volatiles were determined by adsorption-thermal desorption gas chromatography using a mass selective detector. There were significant differences between the ethyl acetate, methanol, isobutanol, and diethylacetal levels of the control wine and that containing chlorpyrifos residues, although only the ethyl acetate exceeded the olfactory threshold. With regard to the minor volatiles, significant differences were detected in the concentrations of some esters, aldehydes, and acids. However, only isoamyl acetate exceeded the olfactory threshold in wines containing residues of chlorpyrifos, fenarimol, and vinclozolin.

Chlorpyrifos↗
PubMed1999

[Radioimmunoscintigraphy of colorectal cancer using the anti-CEA monoclonal antibody BW 431/26. Final results].

The anti-carcinoembryonic antigen (CEA) antibody, BW 431/26 (Scintimun CEA, Behringwerke, Marburg, Germany ) labeled with technetium pertechnectate (99mTc), is an intact immunoglobulin G1, monoclonal antibody that has been used to image colorectal cancer. Planar and SPECT images of chest, abdomen and pelvis were performed at 10 minutes, 4-6 and 18-24 hours after the intravenous antibody injection. 44 patients were studied and the pathological antibody concentration localization by radioimmunoimaging (RI) were correlated with surgical, clinical and other imaging modality findings to validate the RI. The RI was positive in 29 patients and negative in the other 15 patients. The CEA and CA 19.9 were elevated in the serum of some patients with primary tumors or recurrence. The HAMA were determined in all the patients before and after the RI.

Adult↗
PubMed1999

Percentage of adherence correlates with the risk of protease inhibitor (PI) treatment failure in HIV-infected patients.

OBJECTIVES: To determine the effect of adherence on the rate of protease inhibitor (PI) treatment failure among human immunodeficiency virus (HIV)-infected patients. METHODS: A prospective study of a cohort of 282 patients who initiated PI therapy from March 1996 to December 1997. Adherence was quantified as the percentage of prescribed doses reportedly taken and treatment failure was defined as HIV RNA levels above 200 copies/ml after 1 year on therapy. RESULTS: Overall, 190 patients (67%) missed prescribed doses. However, mean percentage of doses taken was 91% (range, 21-100%). Demographic, virological and immunological characteristics could not predict adherence outcomes. The causes of non-adherence included intolerance or side effects (35%), complexity of treatment (23%), or recurrence in active drug abuse (17%), whereas abandonment owing to HIV-related disease was uncommon (6%). A degree of adherence above 90% correlated significantly with viral suppression [relative risk (RR) 1.69; 95% confidence interval (CI) 1.1-2.56; P<0.01]. In a multivariate analysis, a lower degree of adherence (RR, 0.96; P=0.006), a higher HIV viral load (RR, 2.03; P=0.0001), prior antiretroviral therapy (RR, 2.5; P=0.01), and use of saquinavir-hard gel capsules (saquinavir-HGC) (RR, 1.77; P=0.03) were strongly associated with treatment failure. CONCLUSION: The percentage of adherence and initial HIV viral load are the most important determinants of virological response to PI therapy and non-adherence is related to treatment-related factors in the majority of cases.

Adult↗
PubMed1998

Renal histology in ureteropelvic junction obstruction: are histological changes a consequence of hyperfiltration?

PURPOSE: There are few reports of pathological kidney findings in ureteropelvic junction obstruction in pediatric patients. The role of hyperfiltration in the genesis and progression of these changes has been a matter of debate. We determine whether segmental sclerosis is evidence of hyperfiltration and renal damage in children who underwent surgery for ureteropelvic junction obstruction. MATERIALS AND METHODS: We retrospectively analyzed the clinical records of 38 children with a mean age of 4.4 years with ureteropelvic junction obstruction. Histological changes in biopsies (39 renal units) and nephrectomy specimens (2 renal units) were compared with clinical history, imaging studies and urinary protein excretion. RESULTS: Renal histology was essentially normal in 75% of the biopsies. Focal dilatation of Bowman's space and occasionally of the collecting tubules was noted in a third of this group. Abnormal changes consistent with renal damage were present in 25% of the biopsies, including variable degrees of interstitial chronic inflammation, eosinophilic acellular material within Bowman's space and focal concentric glomerulosclerosis. Severe changes, chronic interstitial fibrosis and inflammation, and diffuse glomerulosclerosis were only found in nephrectomy specimens, while eosinophilic acellular material and glomerulosclerosis were observed in 7 biopsies. In all of these renal units there was evidence of hyperfiltration with bilateral or unilateral ureteropelvic junction obstruction with a contralateral multicystic dysplastic kidney. Urinary protein excretion in 19 patients was increased in obstructed compared with normal contralateral kidneys (p < 0.05). CONCLUSIONS: Hyperfiltration should be considered a mechanism involved in the progression of histological changes in kidneys with ureteropelvic junction obstruction. We suggest that early surgical correction be considered in obstructed kidneys at risk for hyperfiltration.

Child↗