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Biomedical subjects

D Costa

Publications and source records attributed to D Costa.

At least 37 records · Page 2Linked to original sources
PubMed1999

Translocation (11;14)(q13;q32) and preferential involvement of chromosomes 1, 2, 9, 13, and 17 in mantle cell lymphoma.

We have studied 13 cases of histologically confirmed mantle cell lymphomas (MCL) combining cytological-immunological features with conventional cytogenetics and in situ hybridization (ISH) techniques. Peripheral blood smears and lymph node biopsies expressed the typical mantle zone pattern with alpha B-cell phenotype. Most of the cases (11 of 13) had lymphomatous cells in the peripheral blood. Chromosome analysis was carried out on lymphoid cells from peripheral blood and/or lymph node biopsies. Phytohemagglutinin (PHA) and phorbol 12-myristate 13 acetate (TPA) were used as mitogens. Biotin-labeled libraries of whole chromosomes implicated in complex karyotypes were used to improve their interpretation. Clonal chromosome abnormalities were found in 10 of 13 patients (77%); 7 of these had a complex abnormality. The most frequent recurrent structural abnormalities were: t(11;14)(q13;q32), involvement of chromosome 1 (der[1], del[1], dup[1]), chromosome 2 (del[2], der[2]), chromosome 9 (der[9], -9), chromosome 13 (add[13], t[13q]), and chromosome 17 (add[17], der[17], t[17q]). The most frequent numerical abnormalities were monosomy 21 and loss of the Y chromosome.

Adult↗
PubMed1999

Dopaminergic activities in the human striatum: rostrocaudal gradients of uptake sites and of D1 and D2 but not of D3 receptor binding or dopamine.

The human striatum, which receives dopaminergic innervation from the substantia nigra and ventral tegmental area (cell groups A8, A9 and A10), has structural and functional subdivisions both rostrocaudally and dorsoventrally. These relate to motor and non-motor origins of cortical projections and the specific areas of the substantia nigra and ventral tegmental area providing dopaminergic innervation. In the present study, we have evaluated the distribution of a number of dopaminergic parameters in the caudate, putamen and nucleus accumbens at separate coronal levels in a post mortem study in a series of elderly normal individuals aged 55-94 years, with analysis of the effect of post mortem variables. Dopamine D1 receptor density displayed a rostrocaudally declining gradient in the putamen but not in the caudate, such that at levels posterior to the anterior commissure, there was significantly lower D1 binding in the putamen compared to the caudate. The density of dopamine D2 receptors was similar in the putamen and caudate, increasing rostrocaudally. The density of dopamine uptake sites exhibited an increasing rostrocaudal gradient in the caudate, especially ventrally, but not in the putamen, where binding was more constant. The dopamine D3 receptor was concentrated in the ventral striatum, particularly the nucleus accumbens, although there was no evidence of a rostrocaudal gradient. With respect to striosome-matrix compartmentalization, there was no complete segregation, although D1 and D3 receptors were concentrated in striosomes, whereas D2 receptors and uptake sites showed higher density in the matrix. Levels of dopamine were similar in the caudate and putamen, and were significantly elevated at levels including the nucleus accumbens and the anterior commissure. Homovanillic acid and the metabolic index (homovanillic acid/dopamine ratio) were significantly higher in the putamen compared to the caudate, especially at levels from and caudal to the anterior commissure. These distributions of dopamine receptors and metabolic indicators, reflecting the different functional domains of the striatum, are relevant to the interpretation of current in vivo imaging of the dopamine transporter and receptors in neurological and psychiatric disorders. They provide information to assist in the detection of perturbations in expression, in specific diseases, at particular points on rostrocaudal, lateromedial and dorsoventral axes, a level of resolution beyond current neuroimaging capability.

Aged↗
PubMed1999

Thermodynamically self-consistent theories of fluids interacting through short-range forces.

The self-consistent Ornstein-Zernike approximation (SCOZA), the generalized mean spherical approximation (GMSA), the modified hypernetted chain (MHNC) approximation, and the hierarchical reference theory (HRT) are applied to the determination of thermodynamic and structural properties, and the phase diagram of the hard-core Yukawa fluid (HCYF). We investigate different Yukawa-tail screening lengths lambda, ranging from lambda=1.8 (a value appropriate to approximate the shape of the Lennard-Jones potential) to lambda=9 (suitable for a simple one-body modelization of complex fluids like colloidal suspensions and globular protein solutions). The comparison of the results obtained with computer simulation data shows that at relatively low lambda's all the theories are fairly accurate in the prediction of thermodynamic and structural properties; as far as the phase diagram is concerned, the SCOZA and HRT are able to predict the binodal line and the critical parameters in a quantitative manner. At lambda=4 some discrepancies begin to emerge in the performances of the different theoretical approaches: the MHNC remains, on the whole, reasonably accurate in predicting the energy and the contact value of the radial distribution function; the SCOZA predicts well the equation of state up to the highest lambda values investigated. The GMSA and the MHNC underestimate and overestimate, respectively, the liquid coexisting density, while the SCOZA and HRT yield liquid branches that fall between the two former theoretical predictions, although both appear to overestimate the critical temperature somewhat. At higher lambda's the GMSA and MHNC binodals further worsen, while the SCOZA appears to remain usefully predictive. In general, the predictions of all the theories tend to slightly worsen at low temperatures and high density. The determination of the freezing line, performed by means of a one-phase "freezing criterion" (due to other authors) is not particularly satisfactory within either the SCOZA or the MHNC; the GMSA prediction for the freezing line at lambda=7 and 9 is instead able to follow in a qualitative manner the pattern of the solid-vapor coexistence line as determined through computer simulation studies. The necessity of further assessments of the freezing predictions is also discussed. Finally, versions of the GMSA, SCOZA, and HRT that can be expected to be more accurate for interactions with extremely short-ranged attractions are identified.

Journal Article↗
PubMed1999

Assaying the granulocyte-macrophage colony-stimulating factor (GM-CSF) as a mitogen of immature cells in fetal blood cultures.

Based on the presence of immature cells in fetal blood, and in an attempt to shorten the cytogenetic reporting time, three simultaneous one-day culture regimes were established in 23 fetal blood samples: (a) the standard phytohemagglutinin (PHA)-stimulated lymphocytes culture, (b) a culture using the granulocyte-macrophage colony-stimulating factor (GM-CSF) as an alternative mitogen, and (c) an unstimulated culture. Diagnostic success rates achieved by these three methods were as follows: 43 per cent (95 per cent CI: 23-64) (GM-CSF), 30 per cent (95 per cent CI: 12-49) (PHA) and 9 per cent (unstimulated). These three regimes were also assayed in three-day cultures giving 100 per cent diagnostic success rate for the PHA and GM-CSF, and 62 per cent (95 per cent CI: 41-83) for the unstimulated. A moderate correlation was found between the initial concentration of cultured erythroblasts and the metaphase count in one-day GM-CSF-stimulated (r=0.43, p=0.01) and unstimulated (r=0.35, p=0.05) cultures, suggesting that erythroblasts may be in part responsible for the mitotic index observed in these two regime cultures. In conclusion, our experience suggests that immature cells in fetal blood may be successfully cultured for diagnostic purposes.

Cells, Cultured↗
PubMed1999

Trisomy/tetrasomy 21 mosaicism in CVS: interpretation of cytogenetic discrepancies between placental and fetal chromosome complements.

Trisomy/tetrasomy 21 mosaicism was found in chorionic villi (semidirect preparation) obtained from a 40 year old pregnant woman. Since both cell lines were abnormal, the couple elected for pregnancy termination. Placenta and fetal tissue samples were obtained for cytogenetic study. Long term cultured villi showed a non-mosaic trisomy 21 karyotype, while other tissues showed either a normal karyotype or normal/trisomy21 mosaicism. These discrepancies could be explained by a modified "bottle neck" embryogenic model with a trisomic zygote and a non-disjunction event taking place in one of the first divisions. Our case emphasises the need for confirmatory studies in other tissues when mosaicism is encountered in chorionic villi, even if all cell lines are abnormal.

Adult↗
PubMed1999

First-trimester transcervical chorionic villus sampling by biopsy forceps versus mid-trimester amniocentesis: a randomized controlled trial project.

Up to now, no data are available comparing amniocentesis and chorionic villus sampling (CVS) using biopsy forceps. A series of 1313 consecutive women referred to our unit before 12 weeks of pregnancy for fetal cytogenetic analysis because of advanced maternal age, were randomized into CVS with the use of transcervical biopsy forceps or mid-trimester amniocentesis. The diagnostic success rates of the two groups were 98 per cent and 100 per cent, and a second procedure was needed in 4.1 per cent (13/314) and in 0. 3 per cent (1/358), respectively. Follow-up was achieved in 98.7 per cent of the pregnancies. Postprocedure spontaneous fetal losses, until the first week after birth, in the 672 pregnancies that completed the trial accounted for 2.2 per cent (7/314) in the CVS group and 2.8 per cent (10/358) in the amniocentesis group. Although the trial was prematurely discontinued, and therefore the sample size was smaller than initially planned, the results indicate that transcervical CVS was as safe as mid-trimester amniocentesis.

Adult↗
PubMed1999

IL-8, IL-6 and ICAM-1 in serum of paediatric patients undergoing cardiopulmonary bypass with and without cardiocirculatory arrest.

BACKGROUND: The aim of the present study was to evaluate the systemic inflammatory response to CPB in paediatric patients undergoing surgical correction of congenital heart diseases. METHODS EXPERIMENTAL DESIGN: comparative investigation. SETTING: paediatric cardiology hospital INTERVENTION: ICAM-1, IL-8, and IL-6 production were analysed before and during CPB, and after surgery in 9 paediatric patients, submitted to cardiocirculatory arrest (Group A); and in 11 without cardiocirculatory arrest (Group B). MEASURES: ICAM-1, IL-8, and IL-6 production were analysed from arterial samples before and during CPB, and after surgery. RESULTS: In group A vs group B a significant increase of IL-8 was detected during (297+/-250 vs 11+/-19 pg x ml(-1), p<0.001) and after (100+/-230 vs n.d. pg x ml(-1)) surgery and was correlated with the duration of operation (r=0.759; p=0.0001) and clamping time (r=0.738; p<0.05). After surgery in group A, IL-6 levels (35+/-43 pg x ml) were higher than those in group B (2+/-5 pg x ml), and a good correlation was observed between IL-6 and duration of aortic clamping (r=0.714; p=0.048), cardiac arrest, (r=0.714; p=0.048), and length of surgery (r=0.867; p=0.04). CONCLUSIONS: In children who underwent CPB with cardiocirculatory arrest cytokine production seems related to duration of operation and amplified by ischemia-reperfusion phenomena.

Cardiopulmonary Bypass↗
PubMed1998

Reversed end-diastolic umbilical flow in a first-trimester fetus with congenital heart disease.

Reversed end-diastolic umbilical artery velocities and a reduced chorionic sac were first seen at 10 weeks in a pregnancy subsequently showing a normal male karyotype on chorionic villi. Four weeks later Doppler studies demonstrated normal umbilical artery waveforms. At 20 weeks, ultrasound examination of the fetus revealed a mild pericardic effusion, hypoplastic righ heart with hypertrophic myocardium and a single umbilical artery, suggesting pulmonary atresia. After neonatal death, pathological studies confirmed pulmonary atresia. This case suggests that reversed end-diastolic umbilical flow in the first trimester may identify a subgroup of fetuses with a lethal abnormality (heart defect, severe intra-uterine retardation, aneuploidy or others).

Adult↗
PubMed1998

A rabbit model for metabolic studies after burn injury.

BACKGROUND: A rabbit burn model was developed and characterized, which will allow conduct of repeated, noninvasive and more sophisticated in vivo metabolic studies to explore the pathophysiology of burn injury, owing to its larger blood volume and tissue mass than the rat. MATERIALS AND METHODS: A 20% body surface, full thickness burn was applied to the backs of six anesthetized rabbits by immersion into a boiling-water bath for 10 s, followed by resuscitation with saline. Resting energy expenditure (REE) was measured daily in pre- and postburn periods. Whole body protein kinetics were evaluated using L-[1(-13)C]leucine tracer, on the preburn and the third postburn day. Fasting plasma glucose was also measured. RESULTS: A significant elevation of REE began on the second postburn day and reached 34 +/- 8% above the preburn level (P < 0.05, paired t test) on the third postburn day. The fasting plasma leucine flux and oxidation were significantly elevated from their preburn levels (both P < 0.05), indicating an accelerated proteolysis and a more negative body protein balance (P < 0.05); however, the rate of whole body protein synthesis did not differ significantly pre- and postburn injury. Fasting plasma glucose also increased (P < 0.001). on the third postburn day. The burn scar remained intact during the study, without any sign of infection. CONCLUSIONS: The metabolic changes observed in this animal model can be attributed to burn injury per se and they mimic those for flow phase in burn patients. This rabbit burn model should be suitable for exploring mechanistic aspects of the burn-induced changes in metabolism and nutrient balance.

Animals↗
PubMed1998

Abnormal ductus venosus blood flow in trisomy 21 fetuses during early pregnancy.

OBJECTIVE: Our purpose was to assess the ductus venosus blood flow in trisomy 21 fetuses in the first half of pregnancy and the relation of this blood flow to nuchal thickness. STUDY DESIGN: The ductus venosus blood flow has been studied in 534 consecutive fetuses between 10 and 18 weeks of gestation who were undergoing prenatal invasive diagnostic procedures. Before the sampling, the velocity during atrial contraction, the pulsatility index for veins, and the ratio of systole-end-systole to diastole were established in the Doppler waveforms and eventually correlated with the fetal karyotype. RESULTS: Ductus venosus waveforms were successfully obtained in 82% of the pregnancies. Eleven fetuses were found to have trisomy 21; the pulsatility index was abnormally increased (>95th percentile) in 73% (8/11), the ratio of systole-end-systole to diastole was abnormally increased in 45% (5/11), and the velocity during atrial contraction was decreased (<5th percentile) in 27% (3/11). CONCLUSIONS: An abnormally increased ductus venosus pulsatility index was found in a substantial proportion of early trisomy 21 fetuses, and this was apparently independent of nuchal thickening.

Blood Circulation↗
PubMed1998

Natural evolution of nuchal thickness in trisomy-21 fetuses.

OBJECTIVE: To assess the natural evolution of nuchal thickness in trisomy-21 fetuses. METHODS: Serial measurements of nuchal thickness were performed over a 1- to 6-week period in 45 consecutive fetuses with trisomy 21, between the 10th and the 23rd weeks of pregnancy. To avoid a gestational age confounding effect, nuchal thickness also was expressed in standard deviations (SDs) for the corresponding gestational week. In addition, the changes were assessed in terms of the presence of clinical positive thickening, considered as such when the measurement was above 2.5 SD. RESULTS: A mean increase of 1.8 mm (95% confidence interval [CI] 1.3, 2.3) for nuchal thickness was observed for a mean period of 21 days. When corrected by gestational age, the mean increase of 0.3 SD (95% CI -0.2, 0.9) was found to be not significant. No clinically relevant nuchal thickening changes were recorded (51% versus 69%) at re-examination. CONCLUSION: Nuchal thickening at re-examination is observed in a similar proportion of trisomy-21 fetuses as when first observed.

Down Syndrome↗
PubMed1998

Molecular, cytogenetic, and clinical characterisation of six XX males including one prenatal diagnosis.

Cytogenetic analysis, fluorescent in situ hybridisation (FISH), and molecular amplification have been used to characterise the transfer of Yp fragments to Xp22.3 in six XX males. PCR amplification of the genes SRY, RPS4Y, ZFY, AMELY, KALY, and DAZ and of several other markers along the Y chromosome short and long arms indicated the presence of two different breakpoints in the Y fragment. However, the clinical features were very similar in five of the cases, showing a male phenotype with small testes, testicular atrophy, and azoospermia. All these patients have normal intelligence and a stature within the normal male range. In the remaining case, the diagnosis was made prenatally in a fetus with male genitalia detected by ultrasound and a 46,XX karyotype in amniocytes and fetal blood. Molecular analysis of fetal DNA showed the presence of the SRY gene. FISH techniques also showed Y chromosomal DNA on Xp22.3 in metaphases of placental cells. To our knowledge, this is the second molecular prenatal diagnosis reported of an XX male.

DNA-Binding Proteins↗
PubMed1998

Drug-resistant tuberculosis in human immunodeficiency virus infected persons in Italy. The Italian Drug-Resistant Tuberculosis Study Group.

OBJECTIVE: To describe the prevalence and epidemiological-clinical characteristics of tuberculosis (TB) resistance to first-line drugs in Italian human immunodeficiency virus (HIV)-infected subjects. DESIGN: Prospective, observational multicenter (25 Centers of Infectious Diseases) study. Mycobacterium tuberculosis strains from 167 HIV co-infected subjects with TB (149 new cases, 18 relapses) were tested at a central laboratory for susceptibility to rifampin (R), isoniazid (H), pyrazinamide (Z), ethambutol (E) and streptomycin (S) and for DNA fingerprint type. Drug susceptibility results were related to patients' epidemiological, clinical and laboratory features. RESULTS: Drug resistance patterns among new TB cases were as follows: R = 1%, Z = 6%, S = 8%, H + S = 3%, S + Z = 4%. TB resistant to at least R + H (MDR-TB) was detected in 36% of new cases due to an MDR-TB outbreak which was the largest thus far in Europe, involving 7/25 participating institutions, and was demonstrated by conventional and molecular epidemiology evidence. With multivariate analysis, MDR-TB was associated with hospital exposure to MDR-TB (OR = 39.3, P < 0.001) and previous use of anti-TB drugs (OR = 9.8, P = 0.008). CONCLUSION: As drug-resistant tuberculosis in Italy is thus far relatively scarce, detection of a large MDR-TB epidemic among HIV-infected subjects was alarming. Aggressive control measures are urgently needed to prevent the spread of MDR-TB throughout the country and among the general population.

AIDS-Related Opportunistic Infections↗
PubMed1997

Brachycephaly is ineffective for detection of Down syndrome in early midtrimester fetuses.

The aim of this study was to assess the value of fetal brachycephaly in the detection of Down syndrome at 13-18 weeks of pregnancy. The cephalic index (CI) was determined in 555 consecutive chromosomally normal fetuses, and in 38 chromosomal abnormalities, prior to amniocentesis. A CI > 0.85 was observed in 14% (2/14) of the fetuses with Down syndrome and in 11% of the normal fetuses. In conclusion, our data show that brachycephaly is not a useful marker for Down syndrome in early midtrimester fetuses.

Adolescent↗
PubMed1997

Interobserver variability of midtrimester fetal nuchal thickness.

OBJECTIVE: To assess the interobserver variability of ultrasound measured fetal nuchal thickness (NT). STUDY DESIGN: NT was measured in 103 consecutive early midtrimester pregnancies (13-18 weeks) by three ultrasonographists with different levels of expertise, in our Prenatal Unit. Measurements were obtained prior to amniocentesis, blindly in relation to other examiners' values. The Lin's concordance correlation coefficient and the Kappa statistics were used to assess concordance between observed values. RESULTS: Mean differences between pairs of observers ranged from 0.44 to 0.57 mm. A higher concordance correlation between measurements was obtained between the more experienced observers (r = 0.77 versus r = 0.51). When assigning cases with a NT > or = 5 mm to a group at risk for Down's syndrome, a high concordance between experienced ultrasonographists was observed (98% agreement; kappa = 0.90). CONCLUSIONS: Interobserver variability in NT was acceptable between experienced ultrasonographists.

Adult↗
PubMed1997

Thrombosis and restenosis after peripheral angioplasty: does acute 111indium-platelet accumulation predict angioplasty outcome?

OBJECTIVES: Use of platelet deposition to predict failure following angioplasty. DESIGN: Prospective study of angioplasty patients in a 9 months surveillance period. MATERIALS: Thirty-eight successful angioplasty patients. METHODS: Autologous 111indium-labelled platelets were re-injected immediately after angioplasty. Gamma camera and probe measures of radioactivity were obtained daily for 2-4 days and compared to a reference site to obtain a radioactivity ratio. Patient follow up was with duplex and arteriography from day 0 to 9 months or at angioplasty failure. RESULTS: Thirty-one patients remained asymptomatic; two developed acute occlusion and five developed restenosis. Platelet accumulation (increased mean radioactivity ratio) occurred at all angioplasty sites and was significantly higher after acute occlusion (camera: 2.93 and probe: 1.93) compared to asymptomatic patients (camera: 1.25 and probe: 1.15) and restenotic patients (camera: 1.31 and probe: 1.23). Radioactivity ratio was not different in patients who later developed restenosis. CONCLUSION: 111Indium platelet radioactivity effectively detected acute angioplasty reocclusions, but was unable to predict subsequent angioplasty restenosis.

Adult↗