PubMed Health⌕ Search

Biomedical subjects

D Costa

Publications and source records attributed to D Costa.

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

Chlamydia trachomatis and Mycobacterium tuberculosis lung infection in an HIV-positive homosexual man.

A 31-year-old homosexual man, who was human immunodeficiency virus (HIV)-positive was admitted for fever and cough. Chest computed tomography (CT) revealed the presence of diffuse interstitial reticular nodulation, and brain nuclear magnetic resonance imaging showed the presence of nodular frontal lesions. Microscopic examination of sputum and other body fluids showed the presence of acid-fast bacilli and culture-only growth Mycobacterium tuberculosis. Serology for respiratory tract pathogens was negative except for Chlamydia. An antibody titer in the immunoglobulin G (IgG) class of 1:64 for Chlamydia pneumoniae and, unexpectedly, an antibody titer of 1:1024 for C. trachomatis were found. The patient was successfully treated with antituberculosis agents, and clarithromycin, for presumptive chlamydial infection.

AIDS-Related Opportunistic Infections↗
PubMed2001

Evaluation of recombinant Leptospira antigen-based enzyme-linked immunosorbent assays for the serodiagnosis of leptospirosis.

There is an urgent need for development of new serodiagnostic strategies for leptospirosis, an emerging zoonosis with worldwide distribution. We have evaluated the diagnostic utility of five recombinant antigens in enzyme-linked immunosorbent assays (ELISAs) for serodiagnosis of leptospirosis. Sera from 50 healthy residents of a high-incidence region were used to determine cutoff values for 96% specificity. In paired sera from 50 cases of leptospirosis confirmed by the microscopic agglutination test, immunoglobulin G (IgG) but not IgM reacted with the recombinant leptospiral proteins. The recombinant LipL32 IgG ELISA had the highest sensitivities in the acute (56%) and convalescent (94%) phases of leptospirosis. ELISAs based on recombinant OmpL1, LipL41, and Hsp58 had sensitivities of 16, 24, and 18% during the acute phase and 72, 44, and 32% during convalescence, respectively. Compared to sera from healthy individuals, patient sera did not react significantly with recombinant LipL36 (P > 0.05). Recombinant LipL32 IgG ELISA demonstrated 95% specificity among 100 healthy individuals, and specificities ranging from 90 to 97% among 30 dengue patients, 30 hepatitis patients, and 16 patients with diseases initially thought to be leptospirosis. Among 39 Venereal Disease Research Laboratory test-positive individuals and 30 Lyme disease patients, 13 and 23% of sera, respectively, reacted positively with the rLipL32 antigen. These findings indicate that rLipL32 may be an useful antigen for the serodiagnosis of leptospirosis.

Antibodies, Bacterial↗
PubMed2001

An 'injury-time integral' model for extrapolating from acute to chronic effects of phosgene.

The present study compares acute and subchronic episodic exposures to phosgene to test the applicability of the 'concentrationxtime' (CxT) product as a measure of exposure dose, and to relate acute toxicity and adaptive responses to chronic toxicity. Rats (male Fischer 344) were exposed (six hours/day) to air or 0.1, 0.2, 0.5 and 1.0 ppm of phosgene one time or on a repeated regimen for up to 12 weeks as follows: 0.1 ppm (five days/week), 0.2 ppm (five days/week), 0.5 ppm (two days/week), or 1.0 ppm (one day/week) (note that the CxT for the three highest exposures was the same). Animals were sacrificed at 4, 8, and 12 weeks during the exposure and after four weeks recovery. Bronchoalveolar lavage (BAL) was performed 18 hours after the last exposure for each time period and the BAL supernatant assayed for protein. Elevated BAL fluid protein was defined as 'acute injury', diminished response after repeated exposure was defined as 'adaptation', and increased lung hydroxyproline or trichrome staining for collagen was defined as 'chronic injury'. Results indicated that exposures that cause maximal chronic injury involve high exposure concentrations and longer times between exposures, not high CxT products. A conceptual model is presented that explains the lack of CxT correlation by the fact that adaptation reduces an 'injury-time integral' as phosgene exposure is lengthened from acute to subchronic. At high exposure concentrations, the adaptive response appears to be overwhelmed, causing a continued injury-time integral, which appears to be related to appearance of chronic injury. The adaptive response is predicted to disappear if the time between exposures is lengthened, leading to a continued high injury-time integral and chronic injury. It has generally been assumed that long, continuous exposures of rodents is a conservative approach for detecting possible chronic effects. The present study suggests that such an approach my not be conservative, but might actually mask effects that could occur under intermittent exposure conditions.

Animals↗
PubMed2000

Stuttering: an update for physicians.

Stuttering is a disturbance in the normal fluency and time patterning of speech. Developmental stuttering (DS), with or without associated psychiatric illness, is the most common form and includes all cases with gradual onset in childhood that are not the result of acquired brain damage. Persistent developmental stuttering (PDS) is DS that has not undergone spontaneous or speech-therapy-induced remission. Organic models of DS focus on incomplete lateralization or abnormal cerebral dominance. There is also evidence that DS has a significant genetic component to its cause. Neuroimaging research data and the effectiveness of dopamine receptor antagonists in DS seem to support the theory of a hyperdopaminergic origin. Speech therapy remains the main treatment for DS; however, antidepressants can be useful in selected cases. Risperidone, a serotonin-dopamine antagonist, has been shown to be more effective than placebo in decreasing the severity of stuttering. The long-term efficacy and safety of serotonin-dopamine antagonists in DS deserve further study.

Adult↗
PubMed2000

Paternal isodisomy 13 in a normal newborn infant after trisomy rescue evidenced by prenatal diagnosis.

Maternal and paternal uniparental disomy of chromosome 13 have been associated with normal phenotypes. We report on a new case of paternal isodisomy 13 in a phenotypically normal girl. Prenatal diagnosis had shown a 46,XX,-13,der(13;13) karyotype in chorionic villi and a 45,XX,der(13;13) karyotype in amniocytes and fetal blood. Molecular studies demonstrated that the de novo der(13;13) was an isochromosome 13 of paternal origin. This observation supports the lack of imprinting effects on chromosome 13 and trisomy rescue as a mechanism leading to uniparental disomy in cases involving isochromosomes.

Chorionic Villi Sampling↗
PubMed2000

Nuchal thickness evolution in trisomy 18 fetuses.

OBJECTIVE: To assess the natural evolution of nuchal thickness in trisomy 18 fetuses. METHODS: Serial measurements of nuchal thickness were performed over a 1- to 5-week period in 17 fetuses with trisomy 18, from the 10th to the 20th week of pregnancy. To avoid a confounding effect due to gestational age, nuchal thickness was also expressed in standard deviations (SD) for the corresponding gestational week. In addition, the changes were assessed in terms of the presence of clinically positive thickening, considered as such when its measurement was above 2.5 SD for the corresponding gestational week. RESULTS: On the initial nuchal thickness measurement, sensitivity for trisomy 18 decreased from 66% on assessment at 10-13 weeks of gestation to 38% at 14-16 weeks. In serial determinations, a mean increase of 1.3 mm [95% confidence interval (CI), 0.1-2.5] was observed for a mean period of 21 days. When corrected for gestational age, the mean increase of 0.2 SD (95% CI, -1.2 to -1.6) was found to be non-significant. No clinically relevant changes were recorded on re-examination, with nuchal thickening remaining stable in 76% of cases. CONCLUSION: Nuchal thickening at re-examination was observed in a similar proportion of trisomy 18 fetuses as when initially observed.

Adult↗
PubMed2000

Disseminated Mycobacterium terrae infection in a patient with advanced human immunodeficiency virus disease.

Mycobacterium terrae has been rarely implicated in human disease and never in patients infected with human immunodeficiency virus (HIV). We describe an HIV-infected patient with disseminated infection by M. terrae with pulmonary and cutaneous clinical manifestations. M. terrae was isolated from both sputum and urine, and identified by both conventional tests and high-performance liquid chromatography. Clinical and microbiological characteristics of this case are compared with those reported in the literature.

AIDS-Related Opportunistic Infections↗
PubMed2000

Mary O. Amdur.

Explore the source record for details and available documents.

Journal Article↗
PubMed2000

Aerosol delivery of muramyl dipeptide to rodent lungs.

Tuberculosis is the single most serious infectious disease worldwide. The respiratory tract is the primary site of infection by Mycobacterium tuberculosis(MTB). A number of immunogenic components of the cell wall of MTB, if delivered to the lungs as aerosols, can be used to study the local immune response. The site of deposition of these aerosols can be employed to control their residence time in the lungs. Muramyl dipeptide (MDP) aerosols were delivered to alveolar macrophages in the lungs of rodents. Guinea pig macrophages harvested by bronchoalveolar lavage were examined by differential interference contrast microscopy for morphological changes indicative of activation. Bronchoalveolar lavage fluid was analyzed for the presence of alkaline phosphatase, lactate dehydrogenase, N-acetyl-glucosaminidase (NAG), and total protein content. Rat alveolar macrophages were studied for the production of nitric oxide, by induction of nitric oxide synthase. Twenty-four hours following exposure to an aerosol of MDP, alveolar macrophages exhibited morphological characteristics (spreading and pseudopodia), enzyme activity (NAG 50% above control), and production of the reactive intermediate nitric oxide. Rat macrophages subjected to aerosol exposure to MDP when challenged with a second dose of MDP or lipopolysaccharide exhibited a linear dose response as measured by nitric oxide production. These studies indicate that the topical delivery of an MTB bacterial cell wall component, muramyl dipeptide, results in activation of alveolar macrophages. This approach may be useful in elucidating elements of the immune response to MTB.

Acetylmuramyl-Alanyl-Isoglutamine↗
PubMed2000

Rapid diagnosis of acute promyelocytic leukemia by analyzing the immunocytochemical pattern of the PML protein with the monoclonal antibody PG-M3.

The fusion protein, promyelocytic leukemia-retinoic acid receptor (PML-RAR)alpha, generated by the t(15;17) translocation has an abnormal cellular distribution with colocalization of RARalpha and PML proteins. We analyzed the immunostaining pattern of PML protein using the PG-M3 monoclonal antibody directed against the amino terminal portion of PML (retained in wild-type PML and PML-RARalpha fusion protein) in the diagnosis of acute promyelocytic leukemia (APL). In addition, we compared this test with other methods for detecting the PML-RARalpha fusion gene. A normal immunostaining pattern was observed in nonmyeloid disorders and in 78 of 111 acute myeloid leukemias (AMLs). A microgranular pattern was observed in 25 AMLs, all corresponding to APL. These results were concordant with the reverse transcriptase-polymerase chain reaction results for PML-RARalpha fusion gene. Only 1 case positive for the PML-RARalpha transcript showed a normal protein pattern by immunocytochemistry. PML immunostaining was helpful to rapidly differentiate 7 cases with borderline characteristics and to obtain the diagnosis in 2 cases with scarce material. The effectiveness and low cost of this technique support its routine use as a first-line procedure in the differential diagnosis of AML.

Antibodies, Monoclonal↗
PubMed2000

Blast crisis of Ph-positive chronic myeloid leukemia with isochromosome 17q: report of 12 cases and review of the literature.

Isochromosome 17q [i(17q)] is frequently observed in the blast crisis (BC) of chronic myelogenous leukemia (CML). It has been suggested that this chromosome abnormality is associated with special hematological characteristics of the BC, but the information on this subject is scarce. The clinical, hematological and cytogenetic features of patients with i(17q) were analyzed in a series of 121 patients with BC of Ph-positive CML. Twelve patients (10%) displayed an i(17q), representing the third commonest cytogenetic abnormality, after trisomy 8 and Ph chromosome duplication. In seven of the 12 patients the BC was preceded by an accelerated phase, and 10 had more than 10% blood basophils at BC diagnosis. The blast cells had a myeloid phenotype in the 12 patients. Five patients exhibited cytogenetic abnormalities in addition to i(17q), with trisomy 8 and duplication of the Ph chromosome being the alterations most frequently observed. Median survival of patients with i(17q) was 22 weeks, which was not significantly different from the survival of patients with myeloid BC in the overall series. These results are similar to the findings in 181 patients with i(17q) from 12 series of the literature, and confirm the special hematologic profile of BC of CML with this cytogenetic abnormality.

Adolescent↗
PubMed2000

Extracorporeal circulation in ewe's foetus: towards a reliable foetal cardiac surgery protocol. A comparison of two cases.

UNLABELLED: Foetal cardiac surgery is the ultimate goal in the treatment of congenital cardiac malformations. The aim of our research is to elucidate some of the features of the necessarily invasive experimental protocol to be used in an animal model of foetal cardiac surgery. In particular, we assessed the foetal placental reactivity to prolonged cardiac bypass in steady-flow conditions. METHODS: Two cases were selected to show the outcome of prolonged (> 30 minutes) extracorporeal circulation (ECC) instituted without oxygenator under steady-flow assistance. Following the instrumentation of the animal (placement of pressure, flow and myocardial fiber length transducers) and the baseline recordings, a 60-minute bypass period was established with an axial turbopump (Hemopump 14 Fr), after systemic heparinisation and artero-venous cannulation. At the end of the circulatory assistance, the cannulae were removed and a 90 minute observation period followed. The cardiac function was assessed by means of indirectly obtained P-V loops. RESULTS: Case A showed a marked reduction in the end-systolic pressure-volume relationship (ESPVR) during ECC, corresponding to a rightward shift of the P-V loop, with a gradual recovery after the assisted circulation. On the contrary, case B was subjected to progressive placental dysfunction, as evidenced by haemogasanalytical data. Consequently, the haemodynamic data also outlined a negative outcome, with high ESPVR values after bypass. CONCLUSIONS: The present study, while confirming the possibility of cardiac intervention in the foetus, underlines the critical role of minimally invasive protocol to limit both foetal stress and placental dysfunction.

Animals↗
PubMed1999

[Philadelphia chromosome-positive chronic myeloid leukemia in the elderly: presenting features, natural history and survival].

BACKGROUND: Among patients with chronic myeloid leukaemia (CML) old people represent a minority whose disease characteristics are not well known. The aim of the study was to analyze the presenting features, the evolutive course, and the survival of older persons with Ph-positive CML. PATIENTS AND METHODS: Forty-four individuals > 65 years diagnosed with Ph-positive CML in a single centre were compared with 292 younger patients. RESULTS: Comparison of the presenting features of chronic phase Ph-positive CML patients yielded the following significant differences: predominance of female sex (15 males/29 females versus 155/137; p = 0.02), higher proportion of patients with anaemic syndrome (12% versus 2%; p = 0.001), lower frequency of splenomegaly (41% versus 68%; p = 0.001), and higher serum levels of uric acid (p = 0.0006) in the older group. Although the latter patients survived significantly less (median survival 36.6 months, 95% CI: 27-46.2, versus 57.6 months, 95%: 51.2-64.1; p = 0.004), 9 of the 33 deaths registered in this group (27%) occurred in the chronic phase of CML, versus 15 (9%) of the 166 deaths in the younger group (p = 0.003). When chronic phase deaths were excluded and leukaemia-related deaths only considered (i.e., those occurring in the BC or the accelerated phase of CML), old patients still had a shorter survival but the difference was no longer significant. CONCLUSIONS: Ph-positive CML features are essentially the same in older and young individuals, since most of the differences observed are attributable rather to the patients' advanced age than to the leukaemia itself.

Aged↗
PubMed1999

[Glutathione S-transferase GSTM1 and GSTT1 genotypes and susceptibility to lung cancer].

A 1:1 matched population-based case-control study was conducted in Xuanwei City, Yunnan Province, where the lung cancer mortality is among China's highest. In this study there were 86 newly diagnosed lung cancer cases and 86 matched control subjects with the same sex, fuel type used, and age(+/- 2 years). Buccal cells were collected from each subject to determine the genotypes of GSTM1 and GSTT1. It was found that the rate of GSTM1 null genotype was higher in the case group than in the control group, and its odds ratio was 2.39(95% CI: 1.25-4.56). The odds ratio became 2.62(95% CI: 1.33-5.15) when other possible confounding factors such as smoking, COPD, and the lifetime exposure to unvented fuel combustion (tons) were adjusted. No association was found between GSTT1 null genotype and lung cancer. The rate of GSTM1 null genotype in Xuanwei City was found to be similar to those of other Chinese populations.

Case-Control Studies↗
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↗