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I Blanco

Publications and source records attributed to I Blanco.

At least 55 records · Page 3Linked to original sources
PubMed1998

Shell-vial culture and pp65 antigenemia assay in the detection of cytomegalovirus in the first blood sample of renal transplant recipients.

The aim of the study was to compare the efficacy of pp65 antigenemia assay and the shell-vial culture (SVC; viremia) for the diagnosis of cytomegalovirus (CMV) infection in renal transplant recipients, comparing the results obtained in the first blood sample and the total number of blood samples analyzed in this group of patients. During the study period, 70 renal transplant recipients were studied: 44 (62.8%) with CMV infection. The method of sedimentation in a dextran solution for leukocyte extraction was used in the pp65 antigenemia assay. The MRC-5 shell-vial assay was used for CMV isolation from leukocytes (viremia). Eighty blood samples were examined from 70 renal transplant recipients: Of the 44 positive samples studied, in 77.5% of cases, both the antigenemia assay and the SVC were positive. In 16.2%, only the antigenemia assay was positive, and, in 6.2%, only the SVC was positive. In all blood samples studied, the antigenemia was present in 93.7% of cases, and the SVC was present in 83.7% (P = 0.04). If the results obtained in only the first blood sample taken for the diagnosis are studied, then we observe that the antigenemia assay was positive in 39 patients (88.6%), whereas the SVC was positive in 41 patients (93.1%), although the difference was not statistically significant (P = 0.39). It is concluded that the inoculation of all of the leukocytes extracted from blood samples in the SVC seems to produce a slight increase in the sensitivity of the cell culture and that the SVC becomes positive before the antigenemia for the detection of CMV in peripheral blood, especially in the first blood sample.

Antibodies, Monoclonal↗
PubMed1998

Optimization of X-ray mammography and technetium-99m methoxyisobutylisonitrile scintimammography in the diagnosis of non-palpable breast lesions.

The purpose of this study was to evaluate the contribution of technetium-99m methoxyisobutylisonitrile (MIBI) scintimammography to the early diagnosis of breast cancer in 78 patients with non-palpable breast lesions detected by mammography. In all cases biopsy was indicated and they were classified into three groups according to the mammographic findings: high (28), intermediate (30) and low (20) mammographic probability of malignancy. Histological diagnosis confirmed 37 benign and 41 malignant lesions. In the high-probability group 99mTc-MIBI scintimammography changed the four false-positives into true negatives at the expense of two false-negatives; in the intermediate group it changed nine of the 17 false-positives into true-negatives at the expense of one false-negative, and in the low-probability group it changed five of the 16 false-positives into true-negatives without false-negatives. Applying scintimammography to patients included in the intermediate and low-probability groups together, 14 of the 33 mammographic false-positives were changed into true-negatives with 1 false-negative; thus, 41% of the unnecessary biopsies would have been avoided. When MIBI scintimammography was applied to the low-probability group, the negative predictive value was 100% and the unnecessary biopsies would have been reduced by 31%.

Adult↗
PubMed1998

An increase in the number of polymorphonuclear leukocytes inoculated on shell-vial culture increases the sensitivity of this assay in the detection of cytomegalovirus in the blood of immunocompromised patients.

A prospective study was conducted comparing the sensitivity of the pp65 antigenemia assay (AGA) to that of the shell-vial culture (SVC) inoculated with increasing quantities of polymorphonuclear leukocytes (PMNLs) in the detection of cytomegalovirus (CMV) in peripheral blood. From the cellular suspension, three SVCs were inoculated with 200,000, 400,000, and 800,000 PMNLs, respectively. Of the 201 patients studied, 67 (31.9%) had positive results in one of the two analytic tests (AGA or SVC). In this group, 13 (19.4%) presented a negative AGA assay; 13 (19.4%) an AGA of 1; 13 (19.4%) an AGA of between 2 and 5; and 28 (41.8%) an AGA with a value > 6 PMNL-positive x 100,000 PMNLs. The SVC inoculated with 200,000 PMNLs detected the presence of CMV in 42 cases (62.6%); 55 (82%) with 400,000; and 64 (95.5%) with 800,000. Statistically significant differences were observed between the isolation capacities of the SVC inoculated with 200,000 and 400,000, and the SVC inoculated with 800,000 PMNLs (p = 0.0001). In the comparison of the overall sensitivity of the AGA with that of the SVC with 200,000, the AGA was found to be significantly more sensitive (p = 0.0052). When comparing with the SVC with 400,000 PMNLs, the two techniques were found to be equally sensitive; and in the comparison with the SVC with 800,000, the culture displayed a greater detection sensitivity (p = 0.0023). According to these results, it seems evident that the increase in the absolute number of PMNLs inoculated in the SVC leads to a significant increase in the sensitivity of the SVC in the detection of low-level viremia by CMV.

Cytomegalovirus↗
PubMed1998

Carotenoids, retinol and tocopherols in patients with insulin-dependent diabetes mellitus and their immediate relatives.

1. Patients with insulin-dependent diabetes mellitus are classified among the groups at risk for low vitamin status, and recent studies suggest that some degree of supplementation with antioxidants may be beneficial in helping to prevent certain long-term complications of diabetes mellitus. Our objective was to compare the status of the fat-soluble vitamins and antioxidant-related compounds in patients with well-defined insulin-dependent diabetes mellitus with that of their first-degree relatives, controlling seasonal and analytical variability as factors influencing the interpretation of the data. 2. Fifty-four patients with insulin-dependent diabetes mellitus, 214 non-diabetic, first-degree relatives (controls) and 236 unrelated controls were analysed for retinol, tocopherols (alpha and gamma) and main carotenoids in serum (beta-carotene, alpha-carotene, beta-cryptoxanthin, lutein, zeaxanthin and lycopene) by means of a validated HPLC method. 3. Insulin-dependent diabetes mellitus was associated with lower retinol levels and higher levels of beta-carotene, alpha-carotene and beta-cryptoxanthin than sex-matched, first-degree relatives. alpha-Tocopherol, the alpha-tocopherol/cholesterol ratio, gamma-tocopherol, lutein, zeaxanthin and lycopene showed no differences. Retinol and beta-carotene were the variables most closely associated with diabetes. 4. Patients with insulin-dependent diabetes mellitus showed lower serum retinol status together with higher concentrations of provitamin-A carotenoids. Serum fat-soluble antioxidant levels were greater than or equal to those in controls. According to the serum status observed, individuals with diabetes do not require supplementation with alpha-tocopherol or carotenoids, although the need for retinol supplementation in patients with marginal serum levels should be evaluated.

Adolescent↗
PubMed1998

Double-phase Tc-99m sestamibi scintigraphy in the preoperative location of lesions causing hyperparathyroidism.

Hyperparathyroidism (HPT) is one of the most prevalent endocrine diseases, for which the only effective treatment is surgery. The use of imaging techniques in the preoperative localization of the hyperfunctioning glands is the subject of controversy. The purpose of this paper is to assess the use of double-phase scintigraphy with Tc-99m sestamibi in the localization of lesions causing HPT. We used scintigraphy to preoperatively examine 41 patients, 31 of whom had primary HPT and 10 with secondary HPT. We acquired two anterior view planar images of the neck and chest 10 minutes and 3 hours after injection of Tc-99m sestamibi. Final diagnosis, determined with biopsy, was adenoma in 26 patients, 24 of whom had a positive scintigraphic study (sensitivity 92%), with only two false negative results. In the 14 cases of parathyroid hyperplasia, scintigraphy was also positive, and 62% (30/48) of the excised glands were identified by Tc-99m sestamibi. The radioisotope study was of particular interest in the six patients who previously had undergone surgery, since all the studies were positive; in two patients, additional diseased glands were located in the neck, and an ectopic adenoma was found in the remaining four patients. A fifth ectopic lesion was also sestamibi-positive and, in this case, the scintigraphic result was a direct indication for mediastinal surgery. There were no false positive results, even in patients with multinodular goiter. We conclude that, due to its high sensitivity and the ease with which it is performed, double-phase scintigraphy with Tc-99m sestamibi is the preferred technique for the preoperative localization of diseased glands in patients with HPT, especially in cases of parathyroid adenoma, including those with aberrant location. Its use is of particular interest in patients who previously have undergone surgery.

Adenoma↗
PubMed1998

Hepatobiliary scintigraphy for the diagnosis of bile leaks produced after T-tube removal in orthotopic liver transplantation.

Choledochocholedochostomy (CC) over a T-tube is a well-recognized technique for biliary reconstruction in orthotopic liver transplantation (OLT). Bile leaks after T-tube removal are common, having a significant morbidity. The aim of this study was to evaluate the utility of hepatobiliary scintigraphy (HBS) for diagnosing bile leaks in liver transplant patients who develop abdominal pain after T-tube removal. Twenty consecutive patients (14 males, 6 females; mean age 44 years) were studied. The interval between T-tube removal and HBS ranged from 8 to 120 h. Hepatobiliary scintigraphy was carried out after the intravenous injection of 185 MBq 99Tc(m)-mebrofenin. A final diagnosis of bile leak was based on surgical, endoscopic retrograde cholangiopancreatography (ERCP) and ultrasound data, and clinical outcome. There were 13 patients with and 7 without bile leaks. On the scintigraphic images, bile leaks were defined as activity outside the biliary tract which moved along the right paracolic gutter, or the progressive accumulation of activity related to fluid collections as seen on ultrasound. Nine of 12 patients needed surgical repair; the other 3 were treated with endoscopic sphincterotomy. One patient with a negative HBS developed an abdominal abscess after aspirative puncture of a biloma. In the seven patients without bile leaks, all scintigrams showed normal biliary transit of activity. A diagnosis of no bile leaks was based on clinical follow-up in five patients and by ERCP in two patients. Based on these results, we conclude that HBS is an effective method for the diagnosis of bile leaks after T-tube removal in liver transplant patients.

Adult↗
PubMed1998

[Study of primary hyperparathyroidism by double-phase gammagraphy using Tc99m-MIBI: preoperative detection of pathological glands].

The preoperative use of imaging techniques to localize the diseased glands in primary hyperparathyroidism is still the subject of controversy. This paper assess the use of double-phase 99mTc-MIBI scintigraphy with that purpose. We examined 37 patients with primary hyperparathyroidism before surgical intervention. Two planar images 10 minutes and 3 hours after injection of 99mTc-MIBI were acquired. Final diagnosis was adenoma in 32 patients, 30 of whom had a positive scintigraphy (sensitivity 94%), with only two false negative results. In the other five patients, four with hyperplasia and one carcinoma, scintigraphy was also positive. Radioisotopic study was of particular interest in 5 patients who had undergone previous surgery; in one case, other diseased gland was located in the neck, and an ectopic adenoma was found in the remaining four cases. Two other ectopic lesions were also MIBI positive and, in these cases, scintigraphy was a direct indication for mediastinal surgery. There was no false positive results. We conclude that the high sensitivity and easy performance make double-phase 99mTc-MIBI scintigraphy the technique of choice for the preoperative localization of diseased glands in primary hyperparathyroidism, especially in cases of adenoma. Its use is of particular interest in adenomas with aberrant location and in patients who have undergone previous surgery.

Adenoma↗
PubMed1998

[Contribution of planar scintigraphy and SPECT with Ga-67 in the diagnosis of infectious complications after median sternotomy].

The prognosis of infections complications after median sternotomy depends of precocious diagnoses and depth extension of infection. We wanted to analyze the use of 67Ga scintigraphy in this pathology, comparing planar studies an SPECT. We studied 22 patients with suspect of infection complication after median sternotomy, the final diagnoses were 5 mediastinitis, 10 osteomyelitis and 7 patients with other pathology. 67Ga scintigraphy diagnosed correctly the 5 mediastinitis, 9 of 10 osteomyelitis and descarted both pathology in the other 7 patients. Planar studies only were able to diagnose correctly 3 of 5 mediastinitis and the another 2 were correctly diagnosed by SPECT. 67Ga scintigraphy is useful in the diagnosis of infection complication after median sternotomy and SPECT is better than planar studies in the diagnosis of mediastinitis.

Diagnosis, Differential↗
PubMed1998

Lutein ester in serum after lutein supplementation in human subjects.

Lutein, one of the major carotenoids present in serum, is also widely consumed by most populations. For the purpose of testing the potential health benefits of several carotenoids, lutein was supplied as part of an intervention trial to test whether the consumption of these food constituents reduces oxidative damage to human tissue components. Lutein from a natural source (15 mg/d as mixed ester forms) was supplied for 4 months to eighteen non-smoking, apparently healthy volunteers (nine men, nine women) aged 25-45 years. The serum carotenoid profile was analysed at baseline and monthly thereafter. On average, lutein concentrations increased 5-fold after the first month of supplementation (mean 1.34 (range 0.6-3.34) mumol/l). On reviewing the results, in those volunteers whose lutein levels surpassed 1.05 mumol/l (fourteen of seventeen), we tentatively identified lutein monopalmitate along with another unidentified ester (possibly from a monoketocarotenoid) in serum. Lutein levels returned to baseline values and ester forms were not present 3 months after supplementation was discontinued. Their concentrations did not correlate with, and represented less than 3% of, lutein levels achieved in serum. They were observed before development of, and despite the presence of, carotenodermia. To our knowledge, this is the first time xanthophyll esters have been described in human serum. In view of the fact that xanthophyll esters have not been previously reported in serum and chylomicrons, it seems unlikely that these ester forms would be a reflection of the contents of the capsule. They may indicate a 'ceiling effect' on or saturation of the transport capacity for xanthophylls, and may have been re-esterified in vivo because of the unusual dietary conditions. The determination of the physiological importance of this finding will require further investigation, although neither haematological nor biochemical changes were detected.

Adult↗
PubMed1997

Histamine modulation of glutamate release from hippocampal synaptosomes.

Histamine is widely believed to act as a neuromodulator in the central nervous system. Histaminergic fibers arriving at the hippocampus could be involved in the modulation of glutamatergic neurotransmission. Therefore, we have investigated the effect of histamine on [3H]glutamate release from hippocampal synaptosomes by using a superfusion system. Calcium-dependent [3H]glutamate release was stimulated by KCI or 4-aminopyridine. When submaximal concentrations of the depolarizing agents were used (15 mM KCI or 50 microM 4-aminopyridine), histamine, acting via histamine H1 and H2 receptors, produced a concentration-dependent increase in the evoked release of glutamate. Maximal effect was obtained with 500 microM histamine. Histamine (up to 1 mM) did not modify basal release. These data suggest that histaminergic afferents may modulate activity-dependent glutamatergic presynaptic terminals in the hippocampus.

Animals↗
PubMed1997

Supplementation with lutein (4 months) and alpha-tocopherol (2 months), in separate or combined oral doses, in control men.

As part of a European project to test if 'the consumption of diets rich in carotenoids reduces oxidative damage to human tissue components', 15 mg/day lutein and 100 mg/day alpha-tocopherol were supplied to ten volunteers. alpha-Tocopherol (alone and combined) provoked an increase in alpha-tocopherol and a decrease in gamma-tocopherol serum levels. Lutein levels increased during the first month (given alone) in all controls but they behaved very differently during the following 3 months. Ketocarotenoids (not supplied) increased whereas anhydroluteins (not supplied) did not change, suggesting that they are formed in vivo.

Adult↗
PubMed1997

Determination of the number of blood samples needed for optimal detection of cytomegalovirus viremia in immunocompromised patients using a shell-vial assay.

To establish the number of blood samples necessary for the diagnosis of viremic episodes caused by cytomegalovirus (CMV), a prospective analysis was conducted of 238 patients (38 renal transplant recipients and 200 HIV-infected patients) who developed CMV viremia. The usefulness of samples and the volume of blood required to demonstrate the presence of viremia by CMV was also studied. The first blood sample was diagnostic for CMV viremia in 53.3% of the viremic patients; the second sample documented an additional 22.2% of cases of viremia (75.5% of infected patients); and the third sample demonstrated viremia in the remaining 24.5%. Thus, a diagnosis of CMV viremia was established in every patient (100% of episodes of viremia). In this study, the use of three 3 ml blood samples collected at 24 h intervals was sufficient to detect all episodes of CMV viremia in patients clinically suspected to have disseminated disease.

Cytomegalovirus Infections↗
PubMed1997

Evaluation of a direct immunofluorescence cytospin assay for the detection of herpes simplex virus in clinical samples.

A comparison between a direct immunofluorescence assay (DFA) and the shell-vial culture (SVC) was conducted to evaluate their efficacies according to the quality and origin of the sample and the type of herpes simplex (HSV) responsible for the infection. The SVC detected all 58 HSV-infected samples, while the DFA detected only 49 (84.5%) positive samples. The DFA detected HSV type 1 in 22 of 89 samples (24.7%) and HSV type 2 in 27 of 96 samples (28.1%). Compared with the SVC, the DFA had a sensitivity of 75.8% for HSV type 1 and 93.1% for HSV type 2. The sensitivity of the DFA depends on the quality of the sample. Thus, while DFA is recommendable as a screening method, the SVC remains the method of choice for obtaining the maximum diagnostic yield from the sample.

Female↗
PubMed1997

Semi-quantitative assessment of cerebral blood flow with 99mTc-HMPAO SPET in type I diabetic patients with no clinical history of cerebrovascular disease.

In 65 type I diabetic patients we prospectively evaluated brain perfusion by means of single-photon emission tomography after the injection of 740- 1110 MBq of technetium-99m hexamethylpropylene amine oxime. Thirty-five of the patients presented complications secondary to their diabetes. None showed CNS symptoms. A semiquantitative analysis was performed drawing 50 symmetrical regions of interest (ROIs) per patient. The relative contribution of each ROI to the total blood flow in each slice was compared with the relative contribution of the same ROI in a control group of ten healthy volunteers. Relative values of any ROI in the study group higher or lower than the mean +/-2 SD in respect of the same ROI in the control group were considered abnormal. The results revealed hypoperfusion in 207 ROIs in the 65 patients with diabetes mellitus: of these ROIs, 113 were frontal, 10 frontotemporal, 20 temporal, 18 parietal, 11 occipital and 35 cerebellar. A total of 137 ROIs showed hyperperfusion: 17 frontal, 3 frontotemporal, 19 temporal, 18 parietal, 19 parieto-occipital, 29 occipital and 32 cerebellar. Out of 65 type I diabetic patients, 61 showed at least one hypoperfused ROI (P = 0.0064 vs. controls) and 25 showed more than three hypoperfused ROIs. None of the control subjects showed more than three hypoperfused regions (P<0.001). The results obtained demonstrate the existence of subclinical abnormalities of brain blood perfusion in patients with type I diabetes mellitus and no history of cerebrovascular disease, thereby allowing the initiation of intensive preventive measures.

Adult↗
PubMed1997

Antiidiotypic response against murine monoclonal antibodies reactive with tumor-associated antigen TAG-72.

The immune response of 42 gastrointestinal and ovarian cancer patients at 1 month after exposure to murine monoclonal antibodies (B72.3 and CC49) reactive with the tumor-associated antigen TAG-72 was studied. The incidence of human anti-mouse antibody response was 89% to B72.3 and 70% to CC49. To evaluate the antiidiotypic immune response, we developed a serological assay based on affinity chromatography to remove the interference due to the presence of TAG-72, antiisotypic, and antiallotypic immunoglobulins in the serum. Seventy-eight percent of patients who received B72.3 developed an antiidiotypic response; in 33% of the patients, this was the only immune response detected. The antiidiotypic immune response after treatment with CC49 was present in 54% of the patients. Twelve percent of the patients who received CC49 developed an antiidiotypic response in the absence of antiisotypic or antiallotypic immune response. The lower immunogenicity of the variable region of CC49 is encouraging when considering the use of chimeric or humanized antibodies derived from the murine monoclonal antibody CC49 in clinical studies.

Animals↗
PubMed1997

Variability in the intercomparison of food carotenoid content data: a user's point of view.

The availability of reliable information on food composition is essential both for the evaluation of diet and for nutritional research to relate diet to health or disease. In this article, we compare the total and individual carotenoid contents and the retinol equivalents in fruits and vegetables reported in several food composition tables and HPLC studies. The impact of the variability in carotenoid intake was evaluated on the basis of Spanish National Consumption Statistics and on the values for a standard diet. We identify, from a user's point of view, errors concerning identification of the items and the terms used to refer to the compounds. Food composition tables overestimate (by 2 to 48%) the retinol equivalent intake, whereas they underestimate (by 30 to 50%) the total carotenoid intake according to HPLC data. We study the effect of these main sources of error, their impact on dietary assessment and on the classification of relevant contributors, and the possible consequences with respect to proper diet in terms of nutritional assessment and epidemiological studies. Given the different dietary habits among populations and the fact that certain items may be over- or underestimated in databases, the use of a single database may be misleading as to the rate of carotenoid consumption and the "true" nutrient intake in a given population, thus weakening the reliability of the study and resulting in erroneous conclusions.

Carotenoids↗