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Gonçalves-Pereira PM, Oliveira E, Insausti R. [Quantitative volumetric analysis of the hippocampus, amygdala and entorhinal cortex: normative database for the adult Portuguese population]. Rev Neurol 2006; 42:713-22. [PMID: 16775796] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
INTRODUCTION Atrophy of the hippocampus, amygdala and entorhinal cortex can be found in neurodegenerative diseases, head trauma and epilepsy and are expressed by means of volume reductions. The ability to detect these changes quantitatively depends on accurate comparisons with normative databases. AIM To present standard magnetic resonance imaging (MRI) volumes of the mesio-temporal lobe structures and an objective statistical methodology for contrasting pathological states. SUBJECTS AND METHODS Volumes of the right and left hippocampi, amygdalae and entorhinal cortex were measured from MRI in 34 right-handed healthy volunteers, aged 19-52 years. Data were normalized for the individual variation in total intracranial volume. Reproducibility was confirmed by intra/inter-observer tests. The statistical analyses included asymmetry comparisons, correlations between volumes and tests to assess the influence of age, gender and general morphometry (body mass index and height). For each volume, we further defined a normative interval by means of 99% confidence ellipses, accordingly to Hotteling's method. RESULTS Right-left asymmetry in the volumes of the hippocampus and entorhinal cortex was a normal finding. Structures located in the right hemisphere were larger than the left by a small but statistically significant amount. No asymmetry was found in the amygdala. There was no correlation in-between these volumes. Gender differences were exclusively noted in the absolute amygdala volumes (male > female) but were eliminated by the normalization procedure. No effect of age or morphometry was seen in the absolute or normalized volumes (except for a milder correlation between hippocampal volumes and height). Confidence ellipses were built for every structure and provided a precise reading of the data. Particularly, it allowed for a clear distinction of pathological asymmetries and bilateral cases. CONCLUSION These normative volumes serve as a reference for the assessment of pathologic groups within similar age-range. The use of a single graphic representation simplifies the clinical interpretation and enhances the precision of the results.
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Rocha A, Oliveira E, Vilhena MJ, Diaz J, Sousa M. A novel apical midpiece defect in the spermatozoa of a bull without an apparent decrease in motility and fertility. A case study. Theriogenology 2006; 66:913-22. [PMID: 16563484 DOI: 10.1016/j.theriogenology.2006.02.032] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2005] [Revised: 02/06/2006] [Accepted: 02/18/2006] [Indexed: 11/25/2022]
Abstract
Despite some limitations as predictors of fertility, evaluation of sperm morphology and progressive motility is the commonest method to assess viability of frozen/thawed semen. In this article we describe by light and transmission electron microscopy a novel midpiece structural defect observed in 24-36% of frozen/thawed sperm cells from a Charolais bull, used in artificial insemination programs without any apparent ill effect to the fertility. After thawing, the sperm progressive motility ranged from 65 to 80% and the pregnancy rate for all artificial inseminations performed (43%) did not differ (p>0.05) from results obtained with insemination with semen of other bulls (40%). The defect consisted in mitochondrial aplasia at the neck region, mitochondrial segmental elongation and gaps and thickening of the outer dense fibers at the apical region of the midpiece, and loss of the cementing substance and development of plasma membrane extensions in the entire midpiece. No structural abnormalities were found in the capitulum, proximal centriole, striated columns, axoneme, annulus and fibrous sheath. The thickness of the outer fibers returned to normal at the distal region of the midpiece. Based on the examination it is suggested that the alterations might be originally caused by loss of the cementing substance that links mitochondria to the plasma membrane in association with mitochondrial aplasia at the neck region of the midpiece. The abnormality appeared not related to other described sperm defect syndromes, although it shared particular characteristics with the dag defect, segmental aplasia of the mitochondrial sheath, corkscrew defect and pseudodroplet defect.
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Gonçalves Pereira PM, Oliveira E, Rosado P. Apparent diffusion coefficient mapping of the hippocampus and the amygdala in pharmaco-resistant temporal lobe epilepsy. AJNR Am J Neuroradiol 2006; 27:671-83. [PMID: 16552015 PMCID: PMC7976968] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
BACKGROUND AND PURPOSE The purpose of this study is to determine whether interictal apparent diffusion coefficients (ADC) provide a robust means for detecting amygdalo-hippocampal abnormalities in adult patients with localization-related chronic temporal lobe epilepsy (TLE) undergoing presurgical evaluation. METHODS Fifty-five patients and 20 age-matched controls were studied with hippocampal and amygdala ADC maps (HADC and AMYADC), volumes (HCVOL, AMYVOL), T2 relaxometry (HCT2, AMYT2), and hippocampal N-acetylaspartate to choline and creatine/phosphocreatine ratios (HCSI). Mean values and 99% confidence ellipses were computed for the groups. Individual ADC mapping was compared with electroencephalography (EEG) data and further correlated with the quantitative MR measures and with the age at onset and duration of TLE. Moreover, we evaluated the association and the predictive value of HADC and AMYADC with respect to the surgical outcome in a subgroup of patients (n = 21) operated on the side of maximal EEG lateralization and with MR imaging criteria for hippocampal sclerosis, 71% of which became seizure-free. RESULTS In controls, there was no relation between ADC values and age, sex, or right-left asymmetries. In TLE groups with right (n = 29) or left epileptogenic foci (n = 26), group comparisons showed that ADC mapping detected changes ipsilateral to the focus in the hippocampus (P < .01) and the amygdala (P < .05), accordingly with the volumes, T2 maps, and HCSI. Significant Pearson correlations (2-tailed) were obtained between ADC maps and the volume of the hippocampus (r = -0.64) and of the amygdala (r = -0.55; both P < .01), T2 (r = 0.70, r = 0.29; both P < .01), but not with HCSI. Individual ADC analysis showed ipsilateral pathology in 82% of cases (hippocampus) and 35% (amygdala) and included a moderate association between ipsilateral HADC and AMYADC (r = 0.54; P < .01). Bilateral abnormalities were found in 7% (hippocampus) and 5% (amygdala) of cases. Except for HCSI and the amygdala data, there were significant correlations between the asymmetry indices and the duration of epilepsy (HADC: r = 0.42; HCT2: r = 0.50; HCVOL: r = 0.35; all P < .01). Age at onset was associated only with ipsilateral HADC (r = 0.35; P < .01) and HCVOL and HCT2 (both P < .05). The association with postsurgical successes was characteristic of HADC (Fisher exact test, 2-tailed: P =.031; Spearman correlation: r(s) = -0.75; P = .0002), but not AMYADC. The predictive value regarding a favorable outcome was 0.87 (odds ratio 26; 95% confidence interval 2.33-38.86). As determined by regression models, both larger ipsilateral HADCs and asymmetry indices predicted surgical success. CONCLUSION Interictal ADC mapping lateralizes efficiently the lesion side in accordance with the EEG data and might be used to study the differential regional aspects of mesio-temporal sclerosis. HADC--not AMYADC--maps discriminate favorably postoperative outcome and can be added to the multidisciplinary evaluation workout of pharmacoresistant TLE patients.
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Oliveira E, Giavina-Bianchi P, Kalilz J. Value of Determination of Specific IgE Against Recombinant Aspergillus fumigatus Allergens rAsp f1, 2, 3, 4 e 6 in the Diagnosis of Allergic Bronchopulmonary Aspergillosis. J Allergy Clin Immunol 2006. [DOI: 10.1016/j.jaci.2005.12.388] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Teixeira C, Vieira S, Silva N, Savi L, Nasi L, Horer J, Oliveira R, Tonietto T, Wickert R, Cremonese R, Brodt S, Oliveira E, Alves F, Barth J, Trevisan C, Callefe F, Pinto K, Hartmann K, Borges L. Crit Care 2005; 9:P48. [DOI: 10.1186/cc3111] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Pereira PMG, Oliveira E, Secca MF. Assessment of the preferred scout sagittal orientation for temporal lobe imaging with magnetic resonance. MAGNETIC RESONANCE MATERIALS IN PHYSICS BIOLOGY AND MEDICINE 2004; 18:19-25. [PMID: 15583976 DOI: 10.1007/s10334-004-0074-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2004] [Revised: 07/12/2004] [Accepted: 09/07/2004] [Indexed: 11/30/2022]
Abstract
Oblique magnetic resonance imaging of the temporal lobe (tilted orientation) requires a stable reference line with minimum variability. In the clinical setting, where several observers carry out examination of the patients, there is a need to assure minimum inter-observer variability, in order to obtain comparable tilted anatomical planes. This is particularly relevant when performing quantitative imaging (qMRI) of the hippocampus, amygdala and para-hippocampal cortices. In this study, eight experienced observers tested the stability of four sagittal reference lines by manually tracing the posterior commissure-obex (PC-OB) line, the line tangential to the anterior surface of the pons at its most convex point and the lines orthogonal to the main axis of both hippocampi, in ten exams of healthy subjects. The stability of the tracing was assessed by comparing the inter-observer variability expressed by the variances of the measurements. The observers' performance was assessed by comparing the precision of the tracing for each line. We tested the results statistically using Bartlett's test (analysis of the variances of the four lines) followed by Fischer-Snedecor (in order to compare the two lines that had the smallest variance). The PC-OB line and the line tangential to the anterior surface of the pons had smaller inter-observer variances than the orthogonal lines (p < 0.01). In addition, the variance of the PC-OB line was smaller than that of the line tangential to the pons (p < 0.01). There were no significant intra-observer differences in the precision of tracing of any of the lines. We show quantitatively that the PC-OB line is the scout reference that yields the smallest inter-observer variance. Thus, this line should be preferred to improve the reproducibility of temporal lobe imaging while performing tilted coronal and axial sequences, to make quantitative assessments of the hippocampus, amygdala and para-hippocampal cortices.
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Mattson M, Alkhazov G, Atamantchouk AG, Balatz MY, Bondar NF, Cooper PS, Dauwe LJ, Davidenko GV, Dersch U, Dolgolenko AG, Dzyubenko GB, Edelstein R, Emediato L, Endler AMF, Engelfried J, Eschrich I, Escobar CO, Evdokimov AV, Filimonov IS, Garcia FG, Gaspero M, Giller I, Golovtsov VL, Gouffon P, Gülmez E, Kangling H, Iori M, Jun SY, Kaya M, Kilmer J, Kim VT, Kochenda LM, Konorov I, Kozhevnikov AP, Krivshich AG, Krüger H, Kubantsev MA, Kubarovsky VP, Kulyavtsev AI, Kuropatkin NP, Kurshetsov VF, Kushnirenko A, Kwan S, Lach J, Lamberto A, Landsberg LG, Larin I, Leikin EM, Yunshan L, Luksys M, Lungov T, Maleev VP, Mao D, Chensheng M, Zhenlin M, Mathew P, Matveev V, McCliment E, Moinester MA, Molchanov VV, Morelos A, Nelson KD, Nemitkin AV, Neoustroev PV, Newsom C, Nilov AP, Nurushev SB, Ocherashvili A, Oliveira E, Onel Y, Ozel E, Ozkorucuklu S, Penzo A, Petrenko SV, Pogodin P, Procario M, Prutskoi VA, Ramberg E, Rappazzo GF, Razmyslovich BV, Rud VI, Russ J, Schiavon P, Simon J, Sitnikov AI, Skow D, Smith VJ, Srivastava M, Steiner V, Stepanov V, Stutte L, Svoiski M, Terentyev NK, Thomas GP, Uvarov LN, Vasiliev AN, Vavilov DV, Verebryusov VS, Victorov VA, Vishnyakov VE, Vorobyov AA, Vorwalter K, You J, Wenheng Z, Shuchen Z, Zukanovich-Funchal R. First observation of the doubly charmed baryon Xi(+)(cc). PHYSICAL REVIEW LETTERS 2002; 89:112001. [PMID: 12225136 DOI: 10.1103/physrevlett.89.112001] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2002] [Indexed: 05/23/2023]
Abstract
We observe a signal for the doubly charmed baryon Xi(+)(cc) in the charged decay mode Xi(+)(cc)-->Lambda(+)(c)K-pi(+) in data from SELEX, the charm hadroproduction experiment at Fermilab. We observe an excess of 15.9 events over an expected background of 6.1+/-0.5 events, a statistical significance of 6.3sigma. The observed mass of this state is 3519+/-1 MeV/c(2). The Gaussian mass width of this state is 3 MeV/c(2), consistent with resolution; its lifetime is less than 33 fs at 90% confidence.
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Oliveira PV, Oliveira E. Multielement electrothermal atomic absorption spectrometry: a study on direct and simultaneous determination of chromium and manganese in urine. FRESENIUS' JOURNAL OF ANALYTICAL CHEMISTRY 2001; 371:909-14. [PMID: 11769799 DOI: 10.1007/s002160101060] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A study was carried out on the direct determination of Cr and Mn in urine using simultaneous atomic absorption spectrometry (SIMAAS). The heating program conditions, the absorbance signal profiles, the influence of different chemical modifiers, and the urine sample volume delivery into the tube were optimized to perform the calibration with aqueous solutions. Among several chemical modifiers tested, the best recovery and repeatability results were obtained for 3 microg Mg(NO3)2. On using this modifier, the pyrolysis and atomization temperatures for simultaneous determination of Cr and Mn were 1,300 degrees C and 2,500 degrees C, respectively. Urine samples were diluted (1+1) with 2.0% (v/v) HNO3 + 0.05% (w/v) Triton X-100 prepared in high purity water. A 20-microL aliquot of analytical solution and 10 microL of chemical modifier solution were delivered to the graphite tube. The characteristic masses were 7.8 pg for Cr (RSD=4.0%) and 4.6 pg for Mn (RSD=2.6%). The limits of detection were 0.08 microg L(-1) (n=20, 3s) for Cr and 0.16 microg L(-1) (n=20, 3s) for Mn. Recovery studies for 1.0 or 2.5 microg L(-1) of Cr and Mn added to different urine samples showed acceptable results for Cr (100%, RSD=14%) and Mn (88%, RSD=5.6%).
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Martins-Gomes AM, Nicolau J, de Souza DN, Oliveira E. A study of some parameters in stimulated saliva from adolescents with dental fluorosis. J Oral Sci 2001; 43:225-31. [PMID: 11848187 DOI: 10.2334/josnusd.43.225] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
Abstract
In this study, parameters such as the flow rate, buffer capacity, sialic acid, protein and electrolyte concentrations, and amylase and peroxidase activities were analyzed in stimulated whole saliva from adolescents with dental fluorosis. From 135 adolescents (13 and 14 years-old) attending a primary and secondary school in the coastal city of Vitoria-Brazil, 72 were selected to participate in this study. The degree of fluorosis was graded using the TSIF, and was carried out by a calibrated and trained dentist. No variation in the flow rate, pH and buffer capacity, protein concentration or amylase activity was observed between the groups with dental fluorosis and the control group (fluorosis score 0). The peroxidase activity and sialic acid concentration showed some differences compared to the control. Sialic acid concentrations were reduced in the groups with dental fluorosis scores above 2. The concentration of Na was lower in adolescents with dental fluorosis, while Mg concentrations were higher in two fluorosis groups, Ca concentration was reduced in two groups with fluorosis. We conclude, that 13 and 14 year-old adolescents attending a school in the coastal city of Vitoria-Brazil showed no variations relative to some parameters and some variations in relation to others of the salivary parameters studied.
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Barjas E, Pires S, Lopes J, Valente A, Oliveira E, Palma R, Raimundo M, Alexandrino P, Moura MC. Cytomegalovirus acute necrotizing esophagitis. Endoscopy 2001; 33:735. [PMID: 11490397 DOI: 10.1055/s-2001-16215] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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Abstract
The case of a 76-year-old woman with a submucosal tumor of the esophagus, whose principal symptoms were dysphagia and epigastric/retrosternal pain, is reported here. Endoscopy, barium swallow and a CAT scan all pointed to extramucosal localization. The lesion was located in the lower esophagus lying on the stomach fundus. An ulcer in the region of the cardia complicated the tumor. Two sets of conventional biopsies failed to detect malignancy, only inflammation and intestinal metaplasia were seen in the specimens of the mucosa surrounding the ulcer. The endoscopic ultrasonographic findings were an indistinct margin, hypoechogenicity, homogeneous appearance and location within the second and third echographic layer. The surgical resection of the tumor was complemented by an anterior partial fundoplication. The histologic study revealed an inflammatory fibroid polyp, which is a rare, benign, non-capsulated submucosal lesion composed mainly of loose connective tissue and vessels, with an eosinophilic inflammatory component. This lesion is seldom found in the esophagus.
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Ribeiro AL, Moraes RS, Ribeiro JP, Ferlin EL, Torres RM, Oliveira E, Rocha MO. Parasympathetic dysautonomia precedes left ventricular systolic dysfunction in Chagas disease. Am Heart J 2001; 141:260-5. [PMID: 11174350 DOI: 10.1067/mhj.2001.111406] [Citation(s) in RCA: 103] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
BACKGROUND Parasympathetic dysautonomia is an established feature of advanced Chagas cardiomyopathy. However, in the absence of cardiac involvement, the presence of vagal dysfunction remains controversial. In a cross-sectional study, we compared patients with Chagas disease without cardiac involvement and healthy individuals by three different methods to determine whether vagal dysfunction is present in the early phase of Chagas disease. METHODS Sixty-one patients with Chagas disease without cardiac involvement and 38 controls were submitted to respiratory sinus arrhythmia test and 24-hour Holter monitoring. Vagal heart influences were assessed by the expiratory/inspiratory (E/I) ratio, time-domain indexes of heart rate variability (HRV), and by the quantification of a 3-dimensional return map. RESULTS The two groups were comparable in terms of left ventricular ejection fraction and left ventricular end-diastolic dimension. Compared with the control group, patients with Chagas disease had significantly lower values of the E/I ratio (mean +/- SD: 1.38 +/- 0.02 and 1.25 +/- 0.02, P <.004) and short-term indexes of HRV (median [interquartile range]-rMSSD: 23 [18-27] and 17 [13-23], P =.00; pNN50: 11 [7-17] and 6 [2-12], P =.00). P(3), a beat-to-beat HRV index derived from the 3-dimensional return map, also was significantly reduced in the Chagas disease group (mean +/- SD: 118 +/- 5 vs 100 +/- 4, P =.00). None of these indexes of vagal heart control were significantly correlated with left ventricular function or to the presence of esophageal radiologic abnormalities. CONCLUSION Parasympathetic dysautonomia is an independent and early phenomenon in Chagas disease and may precede left ventricular systolic dysfunction.
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Erkan M, Sousa M, Carvalho E, Oliveira E, Baldaia L. Fine silver staining analysis of the nucleolar organizer regions during oogenesis in Penaeus kerathurus (Crustacea, Decapoda). JOURNAL OF SUBMICROSCOPIC CYTOLOGY AND PATHOLOGY 2001; 33:47-57. [PMID: 11686408] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
Abstract
In previtellogenic oocytes, nucleoli showed segregated components, with the dense fibrillar component (DFC) appearing highly developed and presenting several fibrillar centers (FC). The granular component (GC) was less developed and formed a wide-spaced reticulum. Only the DFC appeared stained by silver, with higher intensities being found at its periphery. During early vitellogenesis, the nucleolar components were kept segregated but both the DFC and the GC enlarged, without evident changes being noticed in the silver staining pattern. In mid and late vitellogenesis, the nucleoli showed integrated components, with the DFC being intermeshed with the GC. Both nucleolar components were highly developed, no evident FC were noticed, and silver stained the DFC in a heterogeneous pattern. During cortical vesicle formation, the nuclear chromatin condensed and nucleoli appeared disintegrated, showing high levels of accelerated exportation of silver stained materials. Results suggest that the size of the DFC is kept high and the size of the GC kept low (low rDNA transcription levels and RNP exportation accelerated), in the segregated nucleoli of the previtellogenic oocyte, as the cell stores nuages but shows absence of rough endoplasmic reticulum and thus low protein svnthesis; that the size of the DFC and of the GC is increased in the segregated nucleoli of early vitellogenic oocytes (intermediate levels of rDNA transcription and of protein synthesis), which is in accordance with the appearance of the rough endoplasmic reticulum and of yolk vesicles formed with endogenous and exogenous sources; that during mid and late vitellogenesis the DFC and the GC appear highly developed and integrated (high levels of rDNA transcription and of protein synthesis) as the rough endoplasmic reticulum expands and the large yolk vesicles grow by endogenous synthesis; and that chromatin condense and nucleoli disintegrate (very low levels of rDNA transcription with accelerated RNP exportation) when cortical vesicles are formed.
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Carneiro M, de Figueiredo Antunes CM, Greco M, Oliveira E, Andrade J, Lignani L, Greco DB. Design, implementation, and evaluation at entry of a prospective cohort study of homosexual and bisexual HIV-1-negative men in Belo Horizonte, Brazil: Project Horizonte. J Acquir Immune Defic Syndr 2000; 25:182-7. [PMID: 11103049 DOI: 10.1097/00042560-200010010-00013] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND AND OBJECTIVES Project Horizonte, an open cohort of homosexual and bisexual HIV-1-negative men, is a component of the Minas Gerais AIDS Vaccine Program of the Federal University of Minas Gerais, Belo Horizonte, Brazil. Its objectives included the evaluation of seroincidence of HIV, to ascertain the role of counseling on behavior modification and to assess their willingness to participate in future HIV vaccine trials. METHODS Various means of recruitment were used, including pamphlets, notices in community newspapers, radio, and television, at anonymous testing centers, and by word of mouth. RESULTS From October 1994 to May 1999, 470 volunteers were enrolled. Their mean age was 26 years and over 70% of them had high school or college education. During the follow-up, they were seen every 6 months, when they received counseling and condoms, and when HIV testing was done. Eighteen seroconversions were observed, and the incidence rates estimates were 1.75 per 100 and 1.99 per 100 person-years, for 36 and 48 months of follow-up, respectively. During the entire period, 139 volunteers were lost to follow-up. Among them, 59 (42.4%) never returned after the initial visit and 51 (36.7) came only once after their initial visit. No losses were observed for those observed during follow-up for more than 3 years. At enrollment, 50% of participants said they would participate in a vaccine trial, and 30% said they might participate. CONCLUSIONS The results obtained up to this moment confirm the feasibility of following this type of cohort for an extended period, estimating HIV incidence rate, and evaluating counseling for safe sexual practices in preparation for clinical trials with candidate HIV vaccines in Brazil.
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Giménez-Pecci MP, Oliveira E, Resende R, Borgogno C, Nome CF, Laguna IG. Occurrence of Maize rayado fino virus in Maize in Argentina. PLANT DISEASE 2000; 84:1046. [PMID: 30832015 DOI: 10.1094/pdis.2000.84.9.1046d] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Symptoms of fine chlorotic stipple-striping of the veins, chlorosis, numerous dots and stripes, formation of holes in the leaf blade, and ears reduced in size, bearing few grains, were observed in maize crops in Tafí del Valle (Tucumán Province), Orán, El Galpón (Salta Province), Tilcara and Yaví (Jujuy Province), the subtropical area of northwest Argentina where the leafhopper vector Dalbulus maidis (DeLong & Wolcott) is present. Maize rayado fino virus (MRFV) was detected in these samples by a positive reaction in double antibody sandwich-enzyme-linked immunosorbent assay (DAS-ELISA) using an AGDIA kit. Electron microscopy revealed abundant isometric particles about 30 nm in diameter in the cytoplasm and vacuoles of phloem cells and xylem parenchyma cells. The virus was also detected by reverse transcription polymerase chain reaction (RT-PCR) using a primer pair MRFV-09/MRFV-10. Primers and PCR conditions were as previously described (1). Virus amplification was observed only in samples from symptomatic plants. In 1981 (2), the presence of MRFV in Argentina was revealed by serological assay in plants from temperate central areas. No further reports were released since then. This is the first evidence of MRFV in subtropical areas of Argentina and identification of the virus by combining DAS-ELISA, particle size, relation with plant tissues, and RTPCR. References: (1) R. W. Hammond et al. J. Gen. Virol. 78:3153, 1997. (2) S. F. Nome et al. RIA XIX:257, 1984.
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Santos RF, Nomizo R, Oliveira E, Ursich M, Wajchenberg B, Reaven GM, Azhar S. Erythrocyte insulin receptor tyrosine kinase activity is increased in glyburide-treated patients with type 2 diabetes in good glycaemic control. Diabetes Obes Metab 2000; 2:237-41. [PMID: 11225657 DOI: 10.1046/j.1463-1326.2000.00091.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
AIM The goal of this study was to test the hypothesis that insulin receptor tyrosine kinase activity of isolated erythrocytes would be greater in glyburide-treated patients with type 2 diabetes in good glycaemic control (n = 13) than in untreated patients (n = 12) with significant fasting hyperglycaemia. METHODS The two groups were similar in age, sex distribution, and body mass index. By selection, glyburide-treated patients had significantly (p < 0.001) lower (mean +/- s.e.m.) fasting glucose (6.9+/-0.4 vs. 13.9+/-0.8 mmol/l) and HbA(IC) (7.4+/-0.2 vs. 11.8+/-0.9%) concentrations. In addition, insulin-stimulated tyrosine kinase activity was increased in erythrocytes from glyburide -treated patients (p < 0.01). RESULTS Although insulin receptor number was similar in solubilized erythrocytes from the two groups, tyrosine kinase activity per insulin receptor was significantly (p < 0.02) greater in erythrocytes from glyburide-treated patients with type 2 diabetes. CONCLUSIONS These findings are quite similar to previously published data in metformin-treated patients. As such, it is suggested that decreases in insulin receptor tyrosine kinase activity may contribute to the loss of insulin sensitivity in hyperglycaemic subjects (glucotoxicity), and that an improvement in glycaemic control, irrespective of how it is achieved, will help rectify this abnormality.
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Sousa M, Cunha C, Erkan M, Guerra R, Oliveira E, Baldaia L. Chromatin condensation during Scrobicularia plana spermiogenesis: a controlled and comparative enzymatic ultracytochemical study. Tissue Cell 2000; 32:88-94. [PMID: 10798322 DOI: 10.1054/tice.1999.0090] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
In Scrobicularia plana testis, a nuclear acid phosphatase (ACPase) activity was detected in mid and late spermatids with the improved Gomori-chloride procedure. Lead deposits were first observed in mid spermatids at focal points over condensed chromatin strands, increasing in density as chromatin further condensated. In late spermiogenesis, lead deposits became concentrated between chromatin aggregates, and after total DNA compaction were transfered to the nuclear periphery and then shed into the cytoplasm. The specificity of the nuclear ACPase was tested against different pH values (3.9, 7.2, 7.8, 9.0), substrates (TPP, IDP, TMP, p-NCS, ATP, GTP, AMP, ADP, AMP-PNP) and inhibitors (NaF, levamisole, Zn, vanadate, theophylline). To further specify the nature of this nuclear ACPase, other enzymes were comparatively studied at their optimal pH values and at pH 5.0: nucleoside-diphosphatase, thiamin-pyrophosphatase, inorganic trimetaphosphatase, lysosomal arylsulfatases A and B, ATPase, GTPase, 5'-nucleotidase, adenylate kinase, and adenylate cyclase. Several other controls were introduced to exclude artefactual deposits induced by lead ions and tissue molecules. The results showed that the enzyme has an optimal pH at 5.0, a high specific affinity for beta-GP, and is inhibited by NaF, which suggests that it behaves as a type B-ACPase, and all controls demonstrated the specificity of the enzymic activity. Because lead deposits were specifically and temporally associated with spermatid chromatin condensation, when DNA and RNA synthesis, histones, phosphoproteins and RNA molecules strongly decrease, it is possible to suggest that the nuclear ACPase could be associated with DNA processing during chromatin compaction or involved in the hydrolysis of 2' and 3' nucleotides resulting from nuclear RNase action during RNA degradation.
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Correia P, Oliveira E, Oliveira P. Simultaneous determination of Cd and Pb in foodstuffs by electrothermal atomic absorption spectrometry. Anal Chim Acta 2000. [DOI: 10.1016/s0003-2670(99)00761-8] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Lima FR, Fernandes JI, Oliveira E, Fronzaglia GC, Kahn H. Laboratory evaluations of feed-grade and agricultural-grade phosphates. Poult Sci 1999; 78:1717-28. [PMID: 10626647 DOI: 10.1093/ps/78.12.1717] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Nine samples of pure, feed-grade (FP) and agricultural-grade (AP) phosphates were evaluated at seven laboratories (six in Brazil and one in the U.S.) for physical and chemical characteristics. Phosphates were one "standard" pure dicalcium phosphate; four FP, two dicalcium phosphates (FP-1 and FP-2) made in Brazil, one di-monocalcium phosphate (FP-3), and one defluorinated phosphate (FP-4) made in the U.S.; and four AP made in Brazil [single superphosphate (AP-1), triple superphosphate (AP-2) and monoammonium (AP-3), and thermomagnesium (AP-4) phosphates]. Average analytical values for FP and AP, respectively, were 3.3 and 6.3% moisture, 1.0 and 2.5% insoluble residue, 16.2 and 28.4% loss on ignition, 6.8 and 4.7 (pH), 1,028 and 1,023 g/L apparent density, 9.6 and 55.0% P solubility in water, 83.6 and 88.4% P solubility in 2% citric acid, and 85.2 and 97.0% P solubility in neutral ammonium citrate. Based on particle size, six products were classified as "fine," and three were classified as "irregular." Atomic absorption and plasma spectrometry determinations were performed for 31 essential and potentially harmful or radioactive minerals. The Na level was high in FP-4 (6.03%). Mineral concentrations were safe for all FP as compared with NRC standards. Levels in AP were toxic, exceeding the tolerance limits for F, Fe, Mg, and Ba, and were particularly high as compared with FP for S, Ti, and radioactive Th. The AP-1 was high in F, Ba, S, and Th; AP-2 and AP-3 were high in F and S; and AP-4 was high in F, Ba, Fe, Mg, Ti, and Th. X-ray diffraction assays detected impurities for all commercial samples and identified as major components CaHPO4*2H2O (standard phosphate), CaCO3 and CaHPO4 (FP-1, FP-2, and FP-3), Ca(H2PO4)2*H2O (FP-3), Na2Ca3Al2(PO4)2(SiO4)2 and Ca3(PO4)2 (FP-4), CaSO4*nH2O and (NH4)Fe3P6O20*(PO4)2 (AP-1), Ca(H2PO4)2*H2O and KFe3P6O20*10H2O (AP-2), (NH4)H2PO4 and CaSO4*nH2O (AP-3), and no definite molecular structure for AP-4, an amorphous product. The biological consequences of feeding animals a mineral source with no definite molecular structure, an amorphous product, is not known. A biological evaluation of all phosphates included in this article is being published as a separate report (Fernandes et al., 1999).
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Weingartner R, Oliveira E, Oliveira ES, Sant'Anna UL, Oliveira RP, Azambuja LA, Friedman G. Blockade of the action of nitric oxide in human septic shock increases systemic vascular resistance and has detrimental effects on pulmonary function after a short infusion of methylene blue. Braz J Med Biol Res 1999; 32:1505-13. [PMID: 10585632 DOI: 10.1590/s0100-879x1999001200009] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
To investigate the role of nitric oxide in human sepsis, ten patients with severe septic shock requiring vasoactive drug therapy and mechanical ventilation were enrolled in a prospective, open, non-randomized clinical trial to study the acute effects of methylene blue, an inhibitor of guanylate cyclase. Hemodynamic and metabolic variables were measured before and 20, 40, 60, and 120 min after the start of a 1-h intravenous infusion of 4 mg/kg of methylene blue. Methylene blue administration caused a progressive increase in mean arterial pressure (60 [55-70] to 70 [65-100] mmHg, median [25-75th percentiles]; P<0.05), systemic vascular resistance index (649 [479-1084] to 1066 [585-1356] dyne s-1 cm-5 m-2; P<0.05) and the left ventricular stroke work index (35 [27-47] to 38 [32-56] g m-1 m-2; P<0.05) from baseline to 60 min. The pulmonary vascular resistance index increased from 150 [83-207] to 186 [121-367] dyne s-1 cm-5 m-2 after 20 min (P<0.05). Mixed venous saturation decreased from 65 [56-76] to 63 [55-69]% (P<0.05) after 60 min. The PaO2/FiO2 ratio decreased from 168 [131-215] to 132 [109-156] mmHg (P<0.05) after 40 min. Arterial lactate concentration decreased from 5.1 +/- 2.9 to 4.5 +/- 2.1 mmol/l, mean +/- SD (P<0.05) after 60 min. Heart rate, cardiac filling pressures, cardiac output, oxygen delivery and consumption did not change. Methylene blue administration was safe and no adverse effect was observed. In severe human septic shock, a short infusion of methylene blue increases systemic vascular resistance and may improve myocardial function. Although there was a reduction in blood lactate concentration, this was not explained by an improvement in tissue oxygenation, since overall oxygen availability did not change. However, there was a significant increase in pulmonary vascular tone and a deterioration in gas exchange. Further studies are needed to demonstrate if nitric oxide blockade with methylene blue can be safe for patients with septic shock and, particularly, if it has an effect on pulmonary function.
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Antunes E, Rasteiro R, Martins S, Oliveira M, Oliveira E, Menezes M, Cacela D, Soares RM, da Silva N, Gracias R, Antunes AM. [Atrial fibrillation in Wolff-Parkinson-White syndrome]. Rev Port Cardiol 1999; 18:821-7. [PMID: 10536472] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/14/2023] Open
Abstract
The authors describe the main etiopathogenic factors and clinical importance of atrial fibrillation and analyse the results of catheter ablation of atrioventricular accessory pathways in Wolff-Parkinson-White syndrome. Atrial vulnerability is the principal mechanism and radiofrequency catheter ablation of atrioventricular accessory pathways seems to be useless to prevent atrial fibrillation.
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Franzoni L, Nicastro G, Pertinhez TA, Oliveira E, Nakaie CR, Paiva AC, Schreier S, Spisni A. Structure of two fragments of the third cytoplasmic loop of the rat angiotensin II AT1A receptor. Implications with respect to receptor activation and G-protein selection and coupling. J Biol Chem 1999; 274:227-35. [PMID: 9867834 DOI: 10.1074/jbc.274.1.227] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The structural bases that render the third intracellular loop (i3) of the rat angiotensin II AT1A receptor one of the cytoplasmic domains responsible for G-protein coupling are still unknown. The three-dimensional structures of two overlapping peptides mapping the entire i3 loop and shown to differently interact with purified G-proteins have been obtained by simulated annealing calculations, using NMR-derived constraints collected in 70% water/30% trifluoroethanol solution. While the NH2-terminal half, Ni3, residues 213-231, adopts a stable amphipathic alpha-helix, extending over almost the entire peptide, a more flexible conformation is found for the COOH-terminal half, Ci3, residues 227-242. For this peptide, a cis-trans isomerization around the Lys6-Pro7 peptide bond generates two exchanging isomers adopting similar conformations, with an alpha-helix spanning from Asn9 to Ile15 and a poorly defined NH2 terminus. A quite distinct structural organization is found for the sequence EIQKN, common to Ni3 and Ci3. The data do suggest that the extension and orientation of the amphipathic alpha-helix, present in the proximal part of i3, may be modulated by the distal part of the loop itself through the Pro233 residue. A molecular model where this possibility is considered as a mechanism for G-protein selection and coupling is presented.
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Oliveira E, Masunari S. Population relationships between the parasiteAporobopyrus curtatus(Richardson, 1904) (Isopoda: Bopyridae) and one of its porcelain crab hostsPetrolisthes armatus(Gibbes, 1850) (Decapoda: Porcellanidae) from Farol Island, southern Brazil. J NAT HIST 1998. [DOI: 10.1080/00222939800771221] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Carvalho F, Sousa M, Oliveira E, Carvalheiro J, Baldaia L. Ultrastructure of oogenesis in Penaeus kerathurus (Crustacea, Decapoda). I. Previtellogenic oocytes. JOURNAL OF SUBMICROSCOPIC CYTOLOGY AND PATHOLOGY 1998; 30:409-16. [PMID: 9723202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Although Malacostracan species represent an important alimentary human resource, the ultrastructure of oogenesis in P. kerathurus remains unknown. Previtellogenic oocytes of Penaeus kerathurus possess a large nucleus with several peripheral nucleoli. The endoplasmic reticulum (ER) is originated from expansions of the nuclear envelope (NE) and contains small dense granules, which are first formed inside the intermembranous space of the NE but are later exported to the ER lumen. Direct vesiculation from the NE and ER then give rise to the Golgi complexes. Small yolk vesicles appear to be mainly formed by vesiculation of the ER, but also receive materials from the Golgi complexes. They contain a fine fibrillar content which seems to originate from decondensation of the small dense granules. Small vesicles and small multivesicular bodies originated from the NE, ER and Golgi complexes, as also myelin figures directly shedded from the NE, fuse together to give origin to large multivesticular bodies (MVB). These organelles, which have an incomplete membrane and appear meshed within nuage materials, give origin, at a later stage, to lipid droplets that are thereafter extruded into the cytoplasm. Neighbouring oocytes exhibit intercellular bridges, the remaining of their surface being surrounded by a single layer of flattened follicular cells. These results show for the first time in Malacostraca the existence of oocyte intercellular bridges, that the ER and Golgi complexes arise from NE activity, that early yolk formation is endogenous and derives from the activity of the NE, ER and Golgi complexes, and that lipid droplets are products of intracellular membrane recycling activity occurring within large multivesicular bodies.
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Grande RH, Santos JF, Nicolau J, Oliveira E, Singer JM. The influence of a mineralizing mouthrinse on the mineral contents and on the pH of dental plaque. THE JOURNAL OF CLINICAL DENTISTRY 1998; 8:134-7. [PMID: 9487833] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The main objective of this study was to evaluate the effects of a single use of a mineralizing mouthrinse on dental plaque pH and on its mineral contents: an additional objective was to examine the effects of an oral prophylaxis and scaling on the same response variables. A total of 22 volunteer dental students (14 female and 8 male) participated in the study. The mineralizing mouthrinse contained calcium, phosphate, strontium and fluoride ions. Following a 48-hour period without oral hygiene and 2 hours after breakfast, dental plaque was collected twice from each participant for the evaluation of the effects of the oral prophylaxis and scaling, and twice more for the evaluation of the effects of the mineralizing mouthrinse. The pH was measured in vitro with a microelectrode and the mineral contents were determined by atomic emission spectrometry. The results demonstrate that the average post-prophylaxis pH was higher than the average pre-prophylaxis pH, and that a variation of the average contents of some minerals in the dental plaque was also observed after prophylaxis compared to the contents prior to prophylaxis. Although there was a significant reduction in the Fe content after the rinse with the mineralizing solution, no significant variation on the average pH was detected.
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