PubMed Health⌕ Search

Biomedical subjects

C Benito

Publications and source records attributed to C Benito.

At least 19 recordsLinked to original sources
PubMed2001

P300 amplitude as a possible correlate of frontal degeneration in schizophrenia.

The existence of neurodegeneration is a debated issue in schizophrenia research. The P300 component of event-related electrical potentials (ERP) has been related to the different degree of damage to gray and white matter. This study explores the possible relationship between P300 amplitude and/or latency and the existence of degenerative processes in schizophrenia, by assessing its correlation with volume of sulcal CSF and duration of illness, as transversal indicators of neurodegeneration. Nineteen patients (14 males, 5 females) and 13 controls (6 males, 7 females) were studied with MRI and electrophysiological records (P300). The possible influence of sex and age at the time of the exploration was statistically controlled in both groups. The results show a significant negative correlation between P300 amplitude and prefrontal CSF volume in the patient group. A lower though still significant correlation was also found between P300 amplitude and duration of illness, whereas no correlation was found in the control group. These results support the hypothesis that P300 amplitude may be interpreted as a marker of neurodegeneration in schizophrenia.

Adolescent↗
PubMed2001

[Risk factors related to infections during the first year of highly active antiretroviral therapy].

BACKGROUND: To evaluate the immunological, virological and clinical response of HIV-infected patients who start combined therapy with protease inhibitors (PI) in a community hospital. To identify risk factors related with infections. PATIENTS AND METHOD: Clinical review of patients with combined therapy, assessing CD4+ cell counts, viral load (Amplicor) and development of infections during the first year on PI (group A) and comparative study with the same patients during the previous year with PI (group B). RESULTS: 134 patients were included in group A and 84 in Group B. Nadir of CD4+ was 169 X 10(6)/l. After 6 months of PI therapy, the mean CD4 increased from 217 to 355 X 10(6)/l and the median viral load decreased from 88,000 copies/ml (14,000-485,000) to less than 400 copies /ml (< 400-9,000), 60% of patients had less than 400 copies/ml. The incidence of non-opportunistic infections was similar in both groups (36 vs 43%; p = NS). However, the rate of opportunistic infections decreased from 30 to 15% (RR: 0.41 [CI 0.21-0.81]; p = 0.007) in the group with PI, particularly Pneumocystis carinii pneumonia and toxoplasmosis. Multivariated analysis including CD4+ cell count, nadir of CD4+, viral load and risk behavior only nadir of CD4 < 100 X 10(6)/l was associated with a lower risk of developing opportunistic infections (RR: 0.2 [CI: 0.1-0.7]; p = 0.001). CONCLUSIONS: Combined therapy with PI improved immunological and virological markers and decreased the rate of opportunistic infections. A CD4+ cell count nadir higher than 100 X 10(6)/l was a marker of good prognosis during the first year with PI irrespective of response to therapy.

AIDS-Related Opportunistic Infections↗
PubMed2001

Phylogenetic relationships among Portuguese rye based on isozyme, RAPD and ISSR markers.

The phylogenetic relationships of 10 rye landraces and cultivars from the north of Portugal and from Brazil were analysed using 20 isozyme loci, and a total of 511 PCR markers (342 ISSRs and 169 RAPDs). The isozymes were analysed in at least 100 plants of each population/cultivar and, therefore, we have data about intra and inter population/cultivar genetic variability. However, the analyses with ISSRs and RAPDs were obtained using a mix of 25 plants of each population. Therefore, each population/cultivar was reduced to one tube and we have no data about intra genetic variability. As expected in a cross pollinated crop we found genetic diversity and a larger variation within than among the populations using isozymes. Somewhat unexpectedly, however, we found that the breeding cultivars have the same level of heterozygosity as the landraces. The phylogenetic relationships obtained using isozymes among the landraces, synthetic cultivar and the cultivars from breeding programs do not reflect their origin. Moreover, the cultivar from Brazil is not separated from the remaining populations/cultivars studied. However, the data observed using RAPDs and ISSRs are in agreement with their known origin. The populations maintained by the farmers in the north of Portugal are grouped in a cluster in the phenogram and the C902591 (from Brazil), the Alvão (synthetic variety) and Larouco (a hybrid between Montalegre and Brazil) are in a different cluster. The ISSRs and RAPDs provide a rapid method for the production of polymorphic markers, which appear to correspond to known pedigree information.

Alleles↗
PubMed2000

Safety and efficacy of Omniscan (gadodiamide injection) at 0.1 mmol/kg for MRI in infants younger than 6 months of age: phase III open multicenter study.

RATIONALE AND OBJECTIVES: To demonstrate that gadodiamide injection is a safe and efficient contrast agent for MRI in infants younger than 6 months of age. METHODS: The authors designed a phase III multicenter nonrandomized study using a control group. Gadodiamide injection at a dosage of 0.1 mmol/kg body weight was administered to 39 children; 20 received no contrast. The mean age was 10.6 weeks in the contrast group and 9.3 weeks in the control group. MR examinations, blood (serum creatinine, S-ASAT, S-ALAT, S-bilirubin, alkaline phosphatase) and urine (proteins, blood, others) sampling before sedation and after examination, heart rate (electrocardiography) and oxygen saturation (pulse oximetry) during examination, adverse events, and efficacy parameters were analyzed. RESULTS: In the contrast group, 18 (51.4%) children had 31 abnormal changes in one or more of the safety parameters and vital signs. In the control group there were 16 (80.0%) children with 19 abnormal changes. Gadodiamide injection had no negative influence on the safety parameters. No serious adverse events occurred, and only three clinically relevant adverse events (elevation of S-ALAT and S-ASAT, elevation of bilirubin) in two patients in the contrast group and one event (vomiting) in one patient in the control group were documented. The benefit of the contrast medium was clearly shown for all evaluated parameters. CONCLUSIONS: Gadodiamide injection is safe, well tolerated, and effective in infants younger than 6 months of age.

Brain↗
PubMed2000

D-mannoheptulose uptake and its metabolic and secretory effects in human pancreatic islets.

D-mannoheptulose was recently proposed to be transported into cells at the intervention of GLUT2. Since GLUT1, rather than GLUT2, represents the major carrier system for the transport of monosaccharides across the islet B-cell plasma membrane in human subjects, the uptake of D-mannoheptulose and its metabolic and secretory effects were investigated in human islets. The uptake of D-glucose reached much more rapidly a close-to-equilibrium value in isolated islets than in pieces of pancreas obtained from the same donor. The distribution space of D-[3H]mannoheptulose in the human islets largely exceeded that of [U-14C]sucrose, considered as an extracellular marker, and did not differ significantly from that of 3HOH. In the human islets, the heptose (10.0 mM) inhibited both D-[5-3H]glucose utilization and D-[U-14C] glucose oxidation, and decreased glucose-stimulated insulin release to the same extent as D-mannoheptulose hexaacetate. These findings indicate that a suitable radioactive analog of D-mannoheptulose could be used, in human like in rat islets, for preferential labelling of the endocrine moiety of the pancreatic gland.

Carbon Radioisotopes↗
PubMed2000

Achieving plasma HIV RNA below the level of detection in clinical practice.

Clinical trials have shown that highly active antiretroviral therapy (HAART) reduces plasma HIV RNA below the detection level in up to 90 per cent of patients. To assess the independent predictors that are associated with achieving undetectable plasma HIV RNA in the daily clinical practice, we carried out a retrospective study. Among 106 HIV-infected patients treated with HAART, 63 (59 per cent) achieved undetectable plasma HIV RNA (less than 400 copies/ml) at their last visit. Adherence with HAART (greater than 80 per cent of prescribed dose) was self-reported by 81 patients (76 per cent). Independent predictors of achieving undetectable plasma HIV RNA were: self-reported adherence to therapy (Odds ratio [OR] 11.79, 95 per cent Confidence intervals [CI]: 3.55-33.17, p = 0.0001) and lack of previous antiretroviral therapy (OR: 3.12, 95 per cent CI: 1.09-8.96, p = 0.03). The efficacy of antiretroviral therapy observed in the daily clinical practice was noticeably lower than that reported in clinical trials. Patient adherence with prescribed HAART and lack of previous antiretroviral therapy are important factors related to successful therapy in the real world.

Antiretroviral Therapy, Highly Active↗
PubMed1999

The relationship between placental histology and cervical ultrasonography in women at risk for pregnancy loss and spontaneous preterm birth.

OBJECTIVE: Our objective was to determine whether there were any differences in the placental lesions of high-risk patients with versus without ultrasonographic evidence of cervical shortening between 15 and 24 weeks' gestation. STUDY DESIGN: Women who were at risk for pregnancy loss and spontaneous preterm birth were followed by serial transvaginal cervical ultrasonography with transfundal pressure between 15 and 24 weeks' gestation. Two groups of women were identified: those in whom progressive cervical shortening developed to below 2 cm, either spontaneously or induced by transfundal pressure, and those in whom it did not. A perinatal pathologist who was blinded to the pregnancy outcome retrospectively examined placental histologic slides. The histologic placental lesions were categorized as acute or chronic inflammatory lesions, decidual vascular lesions, and coagulation-related lesions. RESULTS: There were 278 women who were followed during the study. Placentas were submitted for histologic examination in 189 cases (125 singleton, 45 twin, and 19 triplet gestations). There were 72 pregnancies with and 117 pregnancies without an ultrasonographic diagnosis of cervical shortening, respectively. Overall, there were significantly more acute inflammatory lesions in patients in whom cervical shortening developed, as determined by ultrasonographic examination. However, there were significantly more decidual vascular lesions in women in whom cervical shortening did not develop. When we examined the distribution of the placental histologic lesions in the 64 cases of multiple gestations, the only significant finding was again a greater frequency of acute inflammatory lesions in patients in whom cervical shortening developed. There was no difference in the distribution of the placental histologic lesion categories among women treated with bed rest versus cervical cerclage because of the ultrasound diagnosis of cervical shortening. CONCLUSION: Acute inflammatory lesions of the placenta were more frequent in patients with second-trimester cervical shortening. These findings support that patients with cervical shortening in the second trimester are prone to acute placental inflammation.

Abortion, Spontaneous↗
PubMed1999

Treatment of TMJ static disk with arthroscopic lysis and lavage: a comparison between MRI arthroscopic findings and clinical results.

Arthroscopic surgery using the lysis and lavage technique was performed on 30 temporomandibular joints (TMJs) of 26 patients with the clinical and radiological (pseudodynamic Magnetic Resonance Imaging) diagnosis of static disk (SD). Parameters of condylar movement, position of the disk in relation to the condyle in open and closed mouth positions and mobility of the articular disk were evaluated both clinically and radiologically using pseudodynamic Magnetic Resonance Imaging (MRI) before and after surgery. Subjective parameters of pain and functional limitation were also evaluated clinically. The results showed that all the clinical and radiological parameters analyzed improved significantly in all the patients included in the study. In view of the results, the authors concluded that SD should be added to the existing categories of TMJ internal derangements. Pseudodynamic MRI is the diagnostic technique of choice in these cases and arthroscopic surgery with lysis and lavage followed by active physical therapy is an effective treatment modality in this type of pathology.

Adult↗
PubMed1999

Colorectal resection and primary anastomosis in patients aged 70 and older: prospective study.

OBJECTIVE: To assess the differences in morbidity, mortality, and other immediate postoperative results of colorectal resection with primary anastomosis in relation to age. DESIGN: Prospective study. SETTING: District hospital, Spain. SUBJECTS: 316 consecutive patients who required colorectal resection with primary anastomosis between 1991 and 1995, 155 of whom were aged <70 years and 161 who were 70 years or more. MAIN OUTCOME MEASURES: Mortality, morbidity, and hospital stay. RESULTS: 116 patients aged <70 (75%) were American Society of Anaesthesiologists (ASA) grades I-II compared with 82 (51%) aged > or =70.33 of the younger patients (21%) and 49 of the older (30%) developed complications. The anastomotic leak rate was 14% (n = 21) in the younger group and 16% (n = 26) among those aged > or =70. Median hospital stay was 14 and 15 days, respectively (ranges 8-81 and 1-120). 4 died (3%) among those aged <70 compared with 17 (11%) in the older group (p = 0.009, chi square 6.9). Mortality for elective resections was 6% (15/263) compared with 11% (6/53) for emergencies. There were no significant differences in mortality according to ASA grade between age groups. CONCLUSIONS: People aged 70 or more are not a high risk group for colorectal resection and primary anastomosis as a result of their age alone. Mortality and morbidity depend more on ASA grade and whether the operation was elective or emergency.

Age Factors↗
PubMed1999

Intestinal obstruction in the elderly. Prognostic factors of mortality.

OBJECTIVES: To analyze mortality-related factors in elderly patients who were operated on for intestinal obstruction, and to determine whether advanced age worsened the morbidity and mortality rates. METHODS: In this prospective study we analyzed 188 patients older than 69 years who were operated on for intestinal obstruction. Group 1 consisted of 82 patients aged between 70 and 79 years, and group 2 consisted of 106 patients aged 80 years and older. We compared the distribution of clinical features and outcomes between the two groups, and determined factors related with mortality (chi-squared test with Yates' correction, Student's t test and multiple logistic regression analysis). RESULTS: The incidence of heart disease was 11% in group 1 and 35% in group 1 (p = 0.0003). There was no difference between the groups in any of the other factors analyzed. Univariate analysis identified as mortality-related factors perianesthetic risk (American Society of Anesthesiologists' Physical Status classification) (p = 0.0005), presence of metastases (p = 0.0001) and delay in surgery (t value = 3.043, p = 0.0027). CONCLUSIONS: Mortality due to surgery for intestinal obstruction in elderly patients is related to perianesthetic risk and delay in surgery. Older age does not increase the morbidity or mortality rates for this type of surgery.

Age Distribution↗
PubMed1998

TMJ static disk: correlation between clinical findings and pseudodynamic magnetic resonance images.

The aim of this study was to analyze the position and mobility of the temporomandibular joint (TMJ) articular disk by means of pseudodynamic magnetic resonance imaging (MRI) and to compare: clinical features, osseus and muscular degenerative changes, the different types of static and their signs and symptoms. The study was performed on 101 patients with clinical and MRI diagnosis of TMJ internal derangement with closed lock (permanent or episodic). On the MRI survey the following was evaluated: disk displacement, disk mobility, condylar translation, bone, and muscular fatty atrophy. Pain was more frequent in static disks (SD) than in mobile disks (MD) in all types of disk displacements (p < 0.01). Condylar translation was always lower in SD than in MD, independently from the position of the articular disk (p < 0.01). Localized sclerosis was more frequent in joints with SD. There were no statistically significant differences in the incidence of fatty atrophy considering disk mobility. The results of the study indicate that clinical diagnosis of closed lock with high frequency is related to the presence of a static disk. Clinical diagnosis of SD can be confirmed with a pseudodynamic MRI survey.

Adolescent↗
PubMed1998

[Integration of multimodal medical images].

Multimodality analysis is becoming a required tool in medical practice due to the development of different image techniques and new imaging processing tools. This paper is a review of the basis of medical image integration, image fusion techniques, and their clinical applications, especially addressing our experience with brain tomographic studies in nuclear medicine and radiology.

Algorithms↗
PubMed1997

Enzyme-linked immunosorbent assay of autoantibodies against mitochondrial glycerophosphate dehydrogenase in insulin-dependent and non-insulin-dependent diabetic subjects.

The mitochondrial enzyme FAD-linked glycerophosphate dehydrogenase (mGDH) plays a key role in the recognition of glucose as a stimulus for insulin release from the pancreatic islet B-cell. In the present study, an ELISA procedure was used for the measurement of mGDH antibodies in both insulin-dependent (IDDM) and non-insulin-dependent (NIDDM) diabetic patients. Positive readings, exceeding the upper limit of the normal range, were recorded in 7 out of 12 IDDM patients, as distinct (P < 0.01) from 2 out of 12 nondiabetic subjects of comparable age. The study conducted in 41 NIDDM patients and 15 control subjects of similar age indicated that the incidence of mGDH-positive cases was not significantly different in the diabetic (4/41) and control (1/15) groups, the measurement of optical density in the positive cases barely exceeding the upper limit of the normal range. These findings indicate that the mitochondrial enzyme mGDH often acts as an antigenic determinant in IDDM, but not in NIDDM, patients.

Adolescent↗
PubMed1996

Immunodetection of mitochondrial glycerophosphate dehydrogenase (mGDH) by a polyclonal antibody raised against a recombinant mGDH fragment product.

The mitochondrial enzyme glycerophosphate dehydrogenase (mGDH) plays an essential role in the B-cell glucose-sensing device and its activity in islet homogenates is impaired in several animal models of type 2 diabetes. We have now developed a polyclonal antibody, raised against a recombinant mGDH fragment product, that could be used for the immunodetection of mGDH. Total RNA was isolated from rat pancreatic islets and used in the synthesis of cDNA. Specific primers were designed that corresponded to the FAD binding domain of mGDH. The PCR product was purified and cloned into an appropriate expression vector used for transformation of Escherichia coli cells. The fusion protein was extracted from the transformed cells, further purified, and used for immunization of rabbits. The antibody recognized a single band of 72 kDa in rat islets and testis. The recombinant mGDH product was also recognized as a single band with the expected 65-kDa reference. An ELISA procedure was designed for detection of antibodies against the recombinant mGDH fragment product. The availability of the mGDH antibody opens the way to a number of further applications such as immunocytochemis- try and mGDH quantification in biological material.

Animals↗
PubMed1996

The efficacy of individual computer heart rate indices in detecting acidemia at birth in growth-restricted fetuses.

OBJECTIVE: To determine the efficacy of individual fetal heart rate (FHR) indices, as determined by computer analysis of the FHR tracing, in detecting fetal acidemia at birth in growth-restricted fetuses. METHODS: The study population consisted of 38 growth-restricted fetuses at 26-37 weeks' gestation from pregnancies with abnormal uterine and/or umbilical artery Doppler velocimetry. The 1-hour FHR tracing was analyzed by computer within 4 hours of cesarean birth before the onset of labor. Umbilical artery cord blood was collected at birth, and pH was determined within 5 minutes of collection. RESULTS: On linear regression, the duration of episodes of low variation in minutes (r = -0.77, r2 = 0.59) and short-term (r = 0.72, r2 = 0.52) and long-term (r = 0.69, r2 = 0.47) variation in milliseconds were significantly related to umbilical artery pH at birth, and more so than the number of accelerations of ten (r = 0.57, r2 = 0.32) and 15 (r = 0.38, r2 = 0.14) beats per minute. There were significant differences in computer measurements of FHR accelerations and variation between the umbilical artery pH categories of acidemia (pH less than 7.20), preacidemia (7.20-7.25), and nonacidemia (greater than 7.25). Stepwise regression revealed that episodes of low variation best described the model for predicting umbilical artery pH at birth (P < .001), with no improvement provided by the addition of other computer-analyzed FHR characteristics. CONCLUSION: In this population of growth-restricted fetuses delivered by elective cesarean, the computer indices of duration of episodes of low variation and short-term and long-term variation were significantly associated with umbilical artery pH and predicted umbilical artery acidemia at birth.

Acidosis↗
PubMed1996

The significance of transvaginal ultrasonographic evaluation of the cervix in women treated with emergency cerclage.

OBJECTIVE: Our purpose was to determine whether perioperative transvaginal ultrasonographic evaluation of the incompetent cervix treated with emergency cerclage is predictive of pregnancy outcome. STUDY DESIGN: Twenty-nine women who underwent emergency cerclage at 16 to 26 weeks of gestation had transvaginal ultrasonographic evaluation of the cervix within 48 hours before and after surgery and at least three times thereafter until 28 weeks of gestation. The following measurements were obtained: (1) funnel width, (2) funnel length, (3) endocervical canal length, (4) the distance between the internal and external os, (5) upper cervix (length of closed endocervical canal above the cervical cerclage), (6) lower cervix (endocervical canal length below suture), and (7) cervical index (1+ Funnel length/Endocervical canal length). Values are reported as the median in millimeters, and statistical analysis was performed by use of the Mann-Whitney U test, Wilcoxon signed-rank test, Spearman rank correlation, 2 x 2 contingency tables, and multiple regression analysis with significance set at p < 0.05. RESULTS: Cerclage procedures resulted in significant improvement in postoperative median measurements of funnel width (15 vs 4.0 mm, p < 0.0001), funnel length (29 vs 3 mm, p < 0.0001), and endocervical canal length (2 vs 27 mm, p < 0.0001). There was a significant relationship between gestational age at delivery and the following measurements: preoperative funnel width (r = -0.51, p = 0.007), postoperative endocervical canal length (r = 0.39, p = 0.04), length of the lower cervix (r = 0.39, p = 0.038), and the cervical index (r = -0.39, p = 0.038). An upper cervical length < 10 mm was a good predictor of delivery before 36 weeks of gestation, sensitivity 85.7% (12/14), specificity 66.7% (10/15), positive predictive value 70.6% (12/17), negative predictive value 83% (10/12), and Fisher's exact p = 0.008. Postoperatively all patients had upper cervical lengths < 10 mm by 28 weeks of gestation. Preoperative digital assessments of cervical dilatation before surgery did not correlate with gestational age at birth (r = -0.031, p = 0.36). CONCLUSIONS: In cases of cervical incompetence treated with emergency cerclage, perioperative transvaginal ultrasonographic assessment of the cervix reveals that the procedure results in improved ultrasonographic status of the cervix and that the ultrasonographic cervical findings before and after surgery correlate with pregnancy outcome.

Adolescent↗