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J Cardoso

Publications and source records attributed to J Cardoso.

At least 37 records · Page 2Linked to original sources
PubMed1997

[Oxygen consumption by indirect calorimetry and Fick equation in swine: role of cardiac output].

OBJECTIVES: To compare O2 uptake values measured by indirect calorimetry (VO2R) with Fick-derived values (VO2Fick) over a wide range of VO2 in experimental conditions and to analyze the influence of cardiac output (QC) on the difference between VO2R and VO2Fick. STUDY DESIGN: Animal study. MATERIAL: Nineteen 2.5-month-old, 29.2 +/- 2.8-kg, Large White pigs. METHODS: A step-by-step decrease in venous return was obtained either by haemorrhage or progressive inferior vena cava and portal veins clamping. Measurements, of 5 to 7 minutes duration included VO2R (Deltatrac), thermodilution QC and arterial and mixed venous blood O2-content. The VO2 values were compared using Bland and Altman's bias analysis. The relationship between QC values and relative error (ER = [VO2R - VO2Fick]/0.5x[VO2R + VO2Fick] was analyzed using a Spearman rank correlation coefficient. RESULTS: The VO2R and VO2Fick arithmetic mean ranged from 108 to 253 mL.min-1 in 130 measurements with broad limits of agreement between both methods. On average, VO2R values were higher than VO2Fick values by +15 +/- 25 mL.min-1. ER significantly decreased with QC (rs = 0.417; P = 0.0001). CONCLUSION: VO2R values exceed VO2Fick values. This bias does not occur in the low QC range, presumably owing to artifactual over estimation of thermodilution QC.

Animals↗
PubMed1997

Parallel distributed processing and executive functioning: Tower of Hanoi neural networkmodel in healthy controls and left frontal lobe patients.

Previous clinical studies have demonstrated that executive functioning has a significant association with the frontal lobes. In this study we examined executive functioning with parallel distributed processing (PDP) methodology by attempting to replicate Tower of Hanoi (TOH) neuropsychological test performance differences in normal healthy controls vs. left frontal lobe patients. Initial theoretical experiments were carried out to solve computer subprocessing constraints of the TOH partially by determining the programming prerequisites for a specific number of rings, efficient sequencing, and a general learning rule. These preliminary studies were then modified using a back-propagation neurocomputational approach. Computer program output showed a resemblance to normal controls' TOH moves. Degrading of the left frontal lobe patients' network resulted in characteristic impairments of executive functioning, i.e., perseveration and rule-braking.

Algorithms↗
PubMed1996

[Complications of two types of pancreatic anastomosis after pancreaticoduodenectomy].

The operative mortality rate after pancreaticoduodenectomy (PD) is 5% or less at major surgical centers and is generally related to pancreatic anastomosis complications. Recently, several authors have reported a low incidence of complications after PD using pancreaticogastrostomy. The aim of our work was to retrospectively study the operative complications of pancreaticogastrostomy (PG) and pancreaticojejeunostomy (PJ) after PD. Since 1989 we have performed 59 consecutive DP, in 33 male patients and 22 female patients, with a mean age of 56 +/- 12 years. We performed 43 PG and 16 PJ. In 42/59 cases, PD was performed for malignant disease. Pancreaticoduodenal resection was identical in both groups, with classical pancreatic transection performed at the level of the mesentericoportal axis. The overall mortality rate in this study was 5.08% (n = 3). It was 4.65% (n = 2) in the PG group and 6.25% (n = 1) in the PJ group. Operative complications were absent in 36 patients (24 PG, 12 PJ). The mean postoperative hospital stay was 17 +/- 6 days; 23 patients (19 PG, 4 PJ) presented one or several complications. 12 patients required re-exploration (10 PG, 2 PJ). Pancreatic fistula occurred in 8 patients (13.55%), 14% (n = 6) in the PG group and 12.5% (n = 2) in the PJ group. In each group, only one pancreatic fistula was re-explored. Seven patients (16%) in the PG group presented postoperative pancreatitis. Pancreatic fistula and postoperative pancreatitis occurred in a pancreas with a normal texture and non-dilated pancreatic duct in every case, with one exception (PJ). During long term follow-up, 18 patients died from cancer (12 PG, 6 PJ). In conclusion, this study suggests that PG does not decrease the pancreatic fistula or postoperative pancreatitis rates and that these complications are essentially related to pancreatic texture and pancreatic duct.

Adult↗
PubMed1995

Use of intravenous immunoglobulin to delay xenogeneic hyperacute rejection. An in vivo and in vitro evaluation.

The delaying action of intravenous immunoglobulin (IVIG) from human origin on hyperacute xenogeneic rejection was assessed in the guinea pig-to-rat combination. IVIG (1500 mg/kg) injected i.v. into Lewis rats 1 hr before grafting significantly prolonged the mean guinea pig heart survival time (167 min, P < 0.005) compared with control injections using NaCl (12 min) or the IVIG glycine vehicle (11 min). The effect of IVIG was also assessed in vitro in the pig-to-human combination. A dose-dependent inhibition of the complement-mediated direct cytotoxicity of human serum on pig RBC was shown using IVIG. The weak direct cytotoxicity of IVIG to pig RBC, which was abolished after preincubating IVIG with pig RBC, was attributed to the anti-pig xenoreactive natural antibodies (XNA) contained in the IVIG preparation. In vitro, XNA-depleted IVIG exerted a significantly stronger inhibitory effect than non-XNA-depleted IVIG, suggesting the use XNA-depleted IVIG in the pig-to-human combination. Although the mechanism of the inhibitory effect of IVIG remains to be clarified, IVIG may represent a new and simple therapeutic modality against xenogeneic hyperacute rejection.

Acute Disease↗
PubMed1995

Dysrhythmic profile of human immunodeficiency virus infected patients.

We prospectively studied, with 24-h Holter monitoring, 21 consecutive human immunodeficiency virus (HIV) infected patients, at all stages of the infection, in order to assess their dysrhythmic profile. Three (14.3%) patients presented one isolated run of supraventricular tachycardia, with < 10 beats, that was considered clinically irrelevant. No patient presented other clinically relevant supraventricular or ventricular tachy or bradydysrhythmias. One (4.8%) patient presented intermittent Mobitz type I second-degree AV block, two (9.5%) patients paroxistic 2:1 AV block and one (4.8%) patient presented a bifascicular block on the 12-lead ECG that persisted during the ambulatory recording. This study suggests that clinically relevant cardiac tachydysrhythmias are rare in our population of HIV infected patients. On the other hand we found an unexpectedly high incidence of cardiac impulse conduction disturbances.

Adult↗
PubMed1995

Long-term delivery of a lysosomal enzyme by genetically modified fibroblasts in dogs.

We have evaluated the feasibility and efficacy of intraperitoneal implants (neo-organs) for protein delivery in large animals. Skin biopsies were taken from four healthy dogs. Primary fibroblast cultures were transduced with a retroviral vector coding for the human beta-glucuronidase. One to six lattices each containing 10(9) skin fibroblasts were implanted into the omentum of the donor animal. Laparotomies performed at regular intervals showed vascularized neo-organs without local inflammation. Human beta-glucuronidase levels equivalent to 0.8 to 3.1% of the endogenous canine activity were detected for up to 340 days on liver biopsy samples. These results indicate that neo-organs can be considered for the long-term delivery of therapeutic proteins or enzymes in humans.

Animals↗
PubMed1995

Comparison of the Amplicor Chlamydia trachomatis test and cell culture for the detection of urogenital chlamydial infections.

OBJECTIVE: To compare the polymerase chain reaction (PCR) Amplicor Chlamydia trachomatis test with the cell culture method, in diagnosing urogenital chlamydial infections. SUBJECTS: 439 patients (327 women and 112 men) attending one STD clinic and Family Planning and Gynaecological Clinics in Lisbon, Portugal, between November 1993 and March 1994. METHODS: In women, two endocervical swab samples were collected: one for PCR Amplicor and one for standard culture technique. Men were asked to submit 20 ml of urine (first pass urine) for PCR Amplicor and one urethral specimen was taken for culture. The order of collection of the specimens was rotated every 50 patients. Discrepant results were further analysed by a second PCR with primers directed against the C trachomatis major outer membrane protein (MOMP) and by direct fluorescent antibody (DFA). RESULTS: After analysis of discrepancies, the adjusted sensitivity and specificity of PCR on endocervical specimens were 92.9% and 100% and the positive and negative predictive values were 100% and 99.7% respectively; on the urine samples these values were 100%, 99.1%, 100% and 99.1%, respectively. CONCLUSION: These results indicate that the PCR Amplicor test is a rapid sensitive and specific assay for the detection of C trachomatis in urogenital infections and provides a non-invasive technique for screening chlamydia infection in men.

Base Sequence↗
PubMed1995

Diltiazem effects on left ventricular function preliminary results of 12 patients evaluated by calibrated apexcardiogram.

Diltiazem is a calcium channel blocker whose effects on left ventricular function (LVF) are controversial. We studied 12 patients with ischemic heart disease (IHD) before starting and 15 and 30 days after having initiated Diltiazem 60 mg t.i.d. LVF was accessed by means of the normalized indexes of the calibrated apexcardiogram: nS for systolic LVF evaluation and nA for diastolic LVF evaluation. Recent works have shown that these indexes have a good correlation with invasive parameters of LVF. We verified that nS did not change and nA decreased significantly (p < 0.05) after Diltiazem. We preliminary concluded that Diltiazem has no deleterious effect on LV systolic function and improves LV diastolic function, by decreasing nA, a parameter which correlates well with LV end diastolic pressure.

Depression, Chemical↗
PubMed1994

Organ xenografting between rodents: an evolutionary perspective.

Rejection times of heart xenografts in several donor-recipient combinations including the guinea pig, rat, hamster, and mouse are examined in light of the paleontological history of rodents and the resulting phylogenetic distances between taxa. This multidisciplinary review at the molecular, chromosomal and morphological levels suggests that xenograft rejection time is inversely proportional to the time divergence or phylogenetic distance, and that the binomial terminology concordant/discordant does not reflect the amplitude of phylogenetic distances.

Animals↗
PubMed1994

Hyperacute xenograft rejection in the swine-to-human donor-recipient combination. In vitro analysis of complement activation.

Complement activation is central to the rejection of discordant xenografts. In order to assess the respective roles of direct and alternative pathways, an in vitro model of hyperacute rejection in the swine-to-human donor-recipient combination was designed, using a complement-dependent cytotoxicity test with swine endothelial cells in culture as targets, and fresh human serum as the source of xenogeneic antibodies and complement. The cytotoxic activity of the sera was evaluated by a colorimetric assay using (3-[4,5-dimethyldiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT). Pure human serum lysed 58 +/- 5% of swine endothelial cells. Selective inhibition of the direct pathway by adding EGTA to the serum reduced cytolysis to 51 +/- 2% (P < 0.01 versus normal serum). Similarly, when using C1q-deficient human sera, only 37 +/- 7% of swine endothelial cells were killed (P < 0.001 versus normal serum). When the alternative pathway was selectively inhibited by heating for 20 min at 50 degrees C, the lytic activity of human serum dropped to 42 +/- 5% (P < 0.001 versus normal serum). Factor B-deficient human serum could only lyse 42 +/- 10% of porcine endothelial cells (P < 0.001 versus normal serum). Syngeneic normal swine serum and heat-inactivated serum were not cytotoxic. Mixing serum with deficient direct pathway and serum with deficient alternative pathway restored the cytotoxicity to normal levels. Similarly, the cytotoxic activity of deficient serum supplemented with purified C1q or factor B at physiological concentrations reached that of normal human serum. In this model of in vitro hyperacute rejection, both pathways of complement activation are involved, suggesting that regimens designed to inhibit hyperacute rejection of swine xenografts into humans should take into account the dual activation of complement in this donor-recipient combination.

Acute Disease↗