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P Rodrigues

Publications and source records attributed to P Rodrigues.

At least 37 records · Page 2Linked to original sources
PubMed2001

Urodynamic pressure flow studies can predict the clinical outcome after transurethral prostatic resection.

PURPOSE: We evaluate whether urodynamic evaluation can determine preoperatively the clinical prognosis of patients treated with transurethral prostatic resection as measured by urinary symptom score and quality of life index. MATERIALS AND METHODS: A total of 253 patients who previously elected transurethral prostatic resection based on clinical symptoms completed the American Urological Association symptom score and quality of life index, and underwent urodynamic evaluation before and after operation. The patients were divided into 7 groups in accordance with detrusor pressure at maximum urinary flow rate. The preoperative and postoperative symptom score and quality of life index were analyzed in each group. RESULTS: Of the patients 42% were not obstructed and could not be distinguished from those who were obstructed preoperatively based on total urinary symptoms (p = 0.95) or subjective impression measured by the quality of life index (p = 0.96). The entire obstructed group demonstrated marked improvement compared to the nonobstructed group (p = 0.018). Analysis of severity also revealed a clear relationship with clinical outcome and subjective satisfaction with obstruction grade, that is the more severely obstructed cases had greater clinical benefit compared to those with little or no obstruction. Furthermore, the nonobstructed subjects did not show any clinical or subjective improvement after transurethral prostatic resection (p = 0.24). CONCLUSIONS: Urodynamic studies provide great predictive value of clinical improvement after prostatic relief but they also properly predict the poor clinical results in nonobstructed patients.

Aged↗
PubMed2001

Transmembrane topology of PiT-2, a phosphate transporter-retrovirus receptor.

PiT-1 and PiT-2 are related multiple transmembrane proteins which function as sodium-dependent phosphate transporters and as the cell receptors of several oncoretroviruses. Two copies of a homology domain that is found in distantly related species assign these proteins to a large family of phosphate transporters. A current membrane topology model of PiT-1 and PiT-2 predicts 10 transmembrane domains. However, the validity of this model has not been addressed experimentally. We addressed this issue by a comprehensive study of human PiT-2. Evidence was obtained for glycosylation of asparagine 81. Epitope tagging showed that the N- and C-terminal extremities are extracellular. The orientation of C-terminal-truncation mutants expressed in cell-free translation assays and incorporated into microsomal membranes was examined by immunoprecipitation. Data were interpreted with respect to previous knowledge about retrovirus binding sites, to the existence of repeated homology domains, and to predictions made in family members. A model in which PiT-2 has 12 transmembrane domains and extracellular N- and C-terminal extremities is proposed. This model, which differs significantly from previous predictions about PiT-2 topology, may be useful for further investigations of PiT-2 interactions with other proteins and for the understanding of PiT-2 transporter and virus receptor functions.

Amino Acid Sequence↗
PubMed2001

Establishment of a diploid reference value for DNA ploidy analysis by image cytometry in mouse cells.

OBJECTIVE: To establish a diploid reference value for DNA ploidy analysis of mouse cells (Mus musculus) by image cytometry using the CAS 200, an analysis system suitable for DNA content studies in human cells. STUDY DESIGN: To establish this standard, we used spleen imprints from 26 normal animals. A minimum of 150 lymphocytes present in each imprint was counted. The mean DNA content (pg/cell) of the G0/G1 peak and the DNA index observed in all samples were statistically analyzed. Cytospins with peritoneal cells from the same animals were then analyzed with this reference DNA value to confirm the diploid range. RESULTS: The DNA diploid reference value was determined by the mean DNA content of all spleen samples, which was 6.42 +/- 0.234 pg/cell, and the diploid range, defined as the diploid value +/- 10%, was 5.78-7.06 pg/cell. All the peritoneal samples showed a DNA diploid histogram, with a mean value for the G0/G1 peak DNA content of 6.742 +/- 0.15. CONCLUSION: The diploid reference value found in this study differs from those reported for other species, including the human being, and should be used in further studies of mouse pathology.

Animals↗
PubMed2000

Redox thermodynamics of low-potential iron-sulfur proteins.

The enthalpy and entropy changes associated with protein reduction (deltaHdegrees,(rc), deltaSdegrees,(rc)) were determined for a number of low-potential iron-sulfur proteins through variable temperature direct electrochemical experiments. These data add to previous estimates making available, overall, the reduction thermodynamics for twenty species from various sources containing all the different types of metal centers. These parameters are discussed with reference to structural data and calculated electrostatic metal-environment interaction energies, and redox properties of model complexes. This work, which is the first systematic investigation on the reduction thermodynamics of Fe-S proteins, contributes to the comprehension of the determinants of the differences in reduction potential among different protein families within a novel perspective. Moreover, comparison with analogous data obtained previously for electron transport (ET) metalloproteins with positive reduction potentials, i.e., cytochromes c, blue copper proteins, and HiPIPs, helps our understanding of the factors controlling the reduction potential in ET species containing different metal cofactors. The main results of this work can be summarized as follows.

Desulfovibrio↗
PubMed2000

Bacillary angiomatosis by Bartonella quintana in an HIV-infected patient.

Bacillary angiomatosis and bacillary peliosis are opportunistic infections caused by Bartonella henselae and Bartonella quintana, which occur in patients with late-stage infection. We report a case of bacillary angiomatosis in an HIV-infected patient with skin, bone, and probably liver involvement, The identification of the agent (B quintana ) was done by polymerase chain reaction in the skin specimen. The patient had complete regression of all lesions after a 6-month regimen of oral erythromycin.

AIDS-Related Opportunistic Infections↗
PubMed2000

Expansions of CD8+CD28- and CD8+TcRVbeta5.2+ T cells in peripheral blood of heavy alcohol drinkers.

BACKGROUND: Despite heavy alcohol consumption, only a low percentage of heavy drinkers develop liver disease. Imbalances in T-cell subsets and iron metabolism parameters are common findings in heavy drinkers, yet the possible role played by discrete T-lymphocyte subsets under heavy alcohol consumption remains unclear. METHODS: To gain new insights into the possible role played by T lymphocytes during alcohol consumption, characterization of CD28 expression and TcR repertoire in peripheral blood CD4+ and CD8+ T cells by two and three-color flow cytometry was performed. A group of heavy alcohol drinkers (AHD, n = 71) and a group of age-matched controls (n = 81), both HLA-phenotyped and HFE-genotyped, constituted the groups under study. RESULTS: Marked expansions of CD28- T cells within the CD8+ but not the CD4+ T-cell pool were observed in AHD compared with controls. These CD8+CD28- expansions were paralleled by expansions of CD8+ T cells bearing specific TcR Valpha/beta chains, namely VP5.2. Moreover, AHD, but not controls, carrying the H63D mutation in the HFE gene showed significantly higher percentages of CD28- T cells within the CD8+ T-cell pool than AHD carrying the normal HFE gene. Finally, high numbers of CD8+CD28- T cells in AHD were associated with lower levels of the liver-related enzymes ALT and GGT. CONCLUSIONS: This study showed that under active ethanol consumption, expansions of discrete CD8+ T-cell subsets occur within the CD8+ T-cell pool, that molecules of the MHC-class I locus seem to influence the extent of the expansions, and that high numbers of CD8+CD28- T cells are associated with low levels of liver enzymes in AHD.

Adult↗
PubMed2000

Importance of lipoprotein metabolism parameters in the clinical and angiographic severity of coronary artery disease.

Coronary artery disease that is clinically and angiographically significant is associated to important biochemical parameters with direct interference in lipoprotein and apoprotein metabolism. The purpose of our study was to evaluate the importance of several lipoprotein metabolic parameters in the clinical and angiographic severity of chronic coronary artery disease. In a population with the diagnosis of ischemic coronary artery disease, we assessed the degree of angiographic (single- versus multivessel disease) and clinical (C.C.S. I-IV classification) severities. In each patient, we determined the value of total cholesterol, triglycerides, HDL and LDL cholesterol, HDL 2 and 3, apoprotein AI and B, lipoprotein (a), anti-phospholipid antibodies and C reactive protein. Our results showed that some parameters were significant in the comparison between a normal group and the global coronary artery disease population, such as the value of total cholesterol, HDL cholesterol, HDL 2, apoprotein AI and B lipoprotein (a) and anti-phospholipid antibodies. In the distinction of coronary artery disease subgroups, in relation to C.C.S. < or = 2 and > or = 3 classes, some factors could be discriminated, such as HDL cholesterol, HDL 2, total cholesterol/HDL, lipoprotein (a), anti-phospholipid antibodies and C reactive protein. In the distinction between classes C.C.S. < or = 2 and AMI, the levels of triglycerides, HDL cholesterol, HDL 2, total cholesterol/HDL, lipoprotein (a) and anti-phospholipid antibodies were significant. In the division between single vessel versus multivessel coronary artery disease we found significant values of HDL cholesterol, HDL 2, total cholesterol/HDL, apoprotein AI, lipoprotein (a), anti-phospholipid antibodies and C reactive protein. In conclusion, our present study endorses the clinical role of lipids and plasma lipoproteins in the determination of several cardiovascular risk factors, but introduction of new parameters such as lipoprotein (a) and the anti-phospholipid antibodies can be very useful for a better and global understanding of the pathophysiological processes and distinction of higher risk subgroups for extension and degree of severity of ischemic coronary artery disease.

Aged↗
PubMed2000

Acid phosphatase, genetic polymorphism and cardiovascular risk factors in a pediatric population.

BACKGROUND: Although the clinical expression of cardiovascular disease usually occurs in adulthood, it is unanimously accepted that atherosclerosis begins in the pediatric age. Because of the early onset of the disease, it is of great importance to screen for major risk factors since pre-school age, especially in risk families. Recent investigations have shown a great interest not only in studying the classic risk factors, but also in the evaluation of oxidative stress and the main antioxidant defense systems. The major cause of this interest is the knowledge of the deleterious effect of reactive oxygen species on lipids, the endothelial membrane of arteries and, finally, on the occurrence of cardiovascular disease. POPULATION AND METHODS: 51 children of both genders, aged 9-12 years, randomly selected from a rural community, were observed. A possible association between low molecular acid phosphatase genetic polymorphism of the erythrocyte and the prooxidant status markers (epinephrine oxidase and low molecular protein phosphotyrosine phosphatase from the erythrocyte), some enzymatic systems of the body antioxidant defense (transmembranar reductase of ferricyanide and metahemoglobin reductase) and finally some intermediate phenotypes of cardiovascular disease (lipid profile and blood pressure) were studied. RESULTS: The study of prooxidant status markers and antioxidant enzymes shows significant differences for acid phosphatase and epinephrine oxidase activities in relation to low molecular acid phosphatase genetic polymorphism, the highest values observed being in those homozygous to the B allele (p < 0.05). The inter-relation study between variables showed, among other things, a significant inverse correlation between acid phosphatase and transmembrane reductase and a direct correlation between apolipoprotein B, acid phosphatase and metahemoglobin reductase. A positive family history for cardiovascular disease also showed a direct and significant correlation to total cholesterol, LDL-cholesterol and apolipoprotein B. CONCLUSIONS: The polymorphic variants of low molecular acid phosphatase and protein phosphotyrosine phosphatase with greater activity are strongly associated, not with the classic parameters of cardiovascular risk factors, but with oxidative stress indicators, such as low molecular protein phosphotyrosine phosphatase and epinephrine oxidase. Family history indicators of cardiovascular risk are clearly associated, since early ages, to some conventional risk factors, such as lipid profile and blood pressure.

Acid Phosphatase↗
PubMed1999

The solution structure of a [3Fe-4S] ferredoxin: oxidised ferredoxin II from Desulfovibrio gigas.

The use of standard 2D NMR experiments in combination with 1D NOE experiments allowed the assignment of 51 of the 58 spin systems of oxidised [3Fe4S] ferredoxin isolated from Desulfovibrio gigas. The NMR solution structure was determined using data from 1D NOE and 2D NOESY spectra, as distance constraints, and information from the X-ray structure for the spin systems not detected by NMR in torsion angle dynamics calculations to produce a family of 15 low target function structures. The quality of the NMR family, as judged by the backbone r.m.s.d. values, was good (0.80 A), with the majority of phi/psi angles falling within the allowed region of the Ramachandran plot. A comparison with the X-ray structure indicated that the overall global fold is very similar in solution and in the solid state. The determination of the solution structure of ferredoxin II (FdII) in the oxidised state (FdIIox) opens the way for the determination of the solution structure of the redox intermediate state of FdII (FdII(int)), for which no X-ray structure is available.

Amino Acid Sequence↗
PubMed1999

Single-cell analysis of glycopeptide resistance gene expression in teicoplanin-resistant mutants of a VanB-type Enterococcus faecalis.

The vanB gene cluster confers resistance to vancomycin but not to the related antibiotic teicoplanin, as the VanRB SB two-component regulatory system triggers expression of the glycopeptide resistance genes only in response to vancomycin. The VanRB regulator activates promoters PRB and PYB for transcription of the regulatory (vanRB SB) and resistance (vanYB WHB BXB) genes respectively. The gfpmut1 gene encoding a green fluorescent protein was fused to PYB to analyse promoter activation in single cells by fluorescence microscopy and flow cytometry. Characterization of 17 teicoplanin-resistant mutants indicated that amino acid substitutions on either side of the VanSB autophosphorylation site led to a constitutive phenotype. Substitutions in the membrane-associated domain resulted in a gain of function, as they allowed induction by teicoplanin. A vanSB null mutant expressed gfpmut1 at various levels under non-inducing conditions, and the majority of the bacteria were not fluorescent. Bacteria grown in the presence of vancomycin or teicoplanin were homogeneously fluorescent. The increase in the number of fluorescent bacteria resulted from induction in negative cells rather than from selection of a resistant subpopulation, indicating that VanRB was activated by cross-talk. Transglycosylase inhibition was probably the stimulus for the heterologous kinase, as moenomycin was also an inducer.

Anti-Bacterial Agents↗
PubMed1999

A randomized, double-blind, placebo-controlled clinical trial of vitamin A in Mozambican children hospitalized with nonmeasles acute lower respiratory tract infections.

OBJECTIVE: The objective of this study was to test the potential of routine vitamin A supplementation at admission to speed up recovery during hospitalization for acute lower respiratory tract infections (ALRI) and to decrease the levels of morbidity at 6 weeks after discharge. The study was conducted in the Central Hospital of Maputo (CHM), Mozambique, from 1995 to 1997. METHODS: Children aged 6-72 months with ALRI admitted to the paediatric wards of the CHM were assigned to a supplementation group (n = 71, receiving 200000 IU of vitamin A) or a control group (n = 93, receiving a placebo). RESULTS: The prevalence of vitamin A deficiency was very high and similar between the two groups. The median number of inpatient days for the supplementation group was 3, for the placebo group 4 days. On day 5 the rate of clinical discharge was 88.4% (n = 61/69) in the experimental intervention group and 73.9% (n = 65/88) in the placebo group (P = 0.023). CONCLUSION We found a statistically significant reduction in duration of admission among vitamin A-supplemented children with ALRI. This effect is in line with what is known about the role of vitamin A in human defence and immune mechanisms and with the serological evidence of the extent of vitamin A deficiency among the children in this trial.

Breast Feeding↗
PubMed1999

Modulation of phosphate uptake and amphotropic murine leukemia virus entry by posttranslational modifications of PIT-2.

PIT-2 is a type III sodium phosphate cotransporter and the receptor for amphotropic murine leukemia viruses. We have investigated the expression and the functions of a tagged version of PIT-2 in CHO cells. PIT-2 remained equally abundant at the cell surface within 6 h following variation of the phosphate supply. In contrast, the efficiency of phosphate uptake and retrovirus entry was inversely related to the extracellular phosphate concentration, indicating that PIT-2 activities are modulated by posttranslational modifications of cell surface molecules induced by phosphate. Conformational changes of PIT-2 contribute to both activities, as shown by the inhibitory effect of sulfhydryl reagents known as inhibitors of type II cotransporters. A physical association of PIT-2 with actin was demonstrated. Modifications of the actin network were induced by variations of the concentrations of extracellular phosphate, cytochalasin D, or lysophosphatidic acid. They revealed that the formation of actin stress fibers determines the cell surface distribution of PIT-2, the internalization of the receptor in response to virus binding, and the capacity to process retrovirus entry. Thus, the presence of PIT-2 at the cell surface is not sufficient to ensure phosphate transport and susceptibility to amphotropic retrovirus infection. Further activation of cell surface PIT-2 molecules is required for these functions.

Actins↗
PubMed1999

Non-coronary sinus of Valsalva aneurysm diagnosed after a road traffic accident.

A 38 year old man with a huge unruptured sinus of Valsalva aneurysm, complicated with severe valvar aortic regurgitation, is described. The aneurysm was detected by echocardiography in the asymptomatic patient who presented with an intense precordial diastolic rumble after a road traffic accident. The patient had successful surgery for the aneurysm and aortic valve replacement. Possible aetiologies for the aneurysm and a brief revision of clinical aspects and treatment are discussed.

Accidents, Traffic↗
PubMed1999

[Myocardial infarct without angiographic coronary atherosclerosis: study of a group of patients].

STUDY OBJECTIVES: Clinical characterization and aspects of subsidiary clinical tests in a group of patients with myocardial infarction with no visible angiographic atherosclerotic stenosis. Etiologic identification, therapeutic approach and prognostic assessment of non atherosclerotic myocardial infarction. PATIENTS: We studied patients admitted with myocardial infarction to coronary care unit over a 4 year period and in whom cardiac catheterism did not show atherosclerotic coronary stenosis (17 patients). METHODOLOGY: Retrospective study; Assessment of clinical characteristics, exercise test parameters, echocardiogram, hemodynamics, heart rate variability (HRV) and signal-averaged electrocardiogram (ECG) of this group of patients; Maximal follow-up of 44 months and minimal of 3 months (average: 19.9 +/- 12.7 months) for the occurrence of ischemic cardiac events (recurrent angina, reinfarction or sudden death). RESULTS: Non atherosclerotic coronary infarction was an unusual situation (2% of the totality of the infarction hospitalized during those 4 years--795 cases), occurring mainly among young men, with few vascular risk factors (except smoking), as small infarctions, without a preferential localization and with good evolution in the acute phase (Killip I). In the predischarge exercise test there was no residual ischemia and functional capacity was generally good. In the majority of cases left ventricular systolic function was preserved (82% of the cases). With cardiac catheterism, we observed two cases of "bridging" and four cases of slow contrast progression. In arrhythmic risk stratification with 24 hours ECG, HRV and high resolution ECG, we observed no adverse prognostic markers in the majority of the cases. The clinical observation of the patients and the tests permitted us to establish probable hypotheses for the etiological diagnoses in 10 of the cases (left main anterior descending artery "bridging"--2 cases; slow contrast progression in the coronary vessels--4 cases, severe aortic stenosis--1 case; left valvular mechanic prosthesis--1 case: probable coronary thrombosis with complete reperfusion after thrombolytic therapy--2 cases). The therapeutic approach in the acute phase was the same as that of atherosclerotic infarctions. Secondary prevention was individualized and according to each case etiology, maintaining the antiplatelet agents. In the follow-up there was unstable angina in 3 patients. There were no cases of reinfarction or sudden death. CONCLUSIONS: This study allowed the characterization of the group of non atherosclerotic myocardial infarction as a group of young men with few vascular risk factors, with small infarctions and good prognosis, without adverse arrhythmic risk markers. It also allowed to identify the probable infarction etiology in 10 patients and the secondary individual prevention for each situation. We noted a good prognosis of this situation at two years.

Adult↗
PubMed1999

[Pulmonary thromboembolism in a female with resistance to activated protein C].

Primary or acquired hypercoagulable states favour thrombotic events. The identification of prothrombotic states is of immediate practical usefulness in the orientation, prophylaxis and treatment of pulmonary embolism. Detection of individuals resistant to activated protein C. the most frequent laboratory anomaly in the study of patients with venous thromboembolism, offers a better approach for these patients as well as a better prophylaxis and orientation of their direct relatives concerning thromboembolic events. The authors describe the clinical case of a young woman, previously healthy, who developed serious pulmonary thromboembolism, the resolution of which was difficult and the evolution unusual. Later, a state of resistance to activated protein C (aPCr) was identified. Concerning the case described, the authors reflect on hypercoagulable situations, especially "aPCr" states.

Activated Protein C Resistance↗
PubMed1999

[Extra-adrenal pheochromocytoma simulating acute myocardial infarction].

The authors present the case of a 65 year-old female who was admitted to the emergency room with epigastric pain, headache, palpitations, nausea, vomiting and sweating. The laboratory tests performed showed elevation of CK and CK-MB and the ECG presented sinus tachycardia. T-wave inversion and prolonged QT interval. The echocardiogram was normal. The patient was admitted to the ICU and during the standard myocardial infarction treatment (including beta-blocker) a wide range of the arterial pressure (230/140 to 70/40 mm Hg) was registered. In view of these new data, the hypothesis of pheochromocytoma and catecholamine induced myocarditis was suggested and later confirmed by high levels of plasmatic and urinary catecholamines. The abdominal echography. CT and MRI showed a large retroperitonal and para-aortic mass. The administration of phenoxybenzamine (30 mg/day) led to the normalization of the ECG and arterial pressure and the respective clinical improvement. The anatomopathological exam, after surgical removal, confirmed our hypothesis. Sixteen months after the surgical procedure the patient is assymptomatic, with normal arterial pressure and normal levels of plasmatic and urinary catecholamines.

Aged↗