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Biomedical subjects

J M Costa

Publications and source records attributed to J M Costa.

At least 19 recordsLinked to original sources
PubMed2005

Development and mapping of microsatellite (SSR) markers in wheat.

Microsatellite DNA markers are consistently found to be more informative than other classes of markers in hexaploid wheat. The objectives of this research were to develop new primers flanking wheat microsatellites and to position the associated loci on the wheat genome map by genetic linkage mapping in the ITMI W7984 x Opata85 recombinant inbred line (RIL) population and/or by physical mapping with cytogenetic stocks. We observed that the efficiency of marker development could be increased in wheat by creating libraries from sheared rather than enzyme-digested DNA fragments for microsatellite screening, by focusing on microsatellites with the [ATT/TAA]n motif, and by adding an untemplated G-C clamp to the 5'-end of primers. A total of 540 microsatellite-flanking primer pairs were developed, tested, and annotated from random genomic libraries. Primer pairs and associated loci were assigned identifiers prefixed with BARC (the acronym for the USDA-ARS Beltsville Agricultural Research Center) or Xbarc, respectively. A subset of 315 primer sets was used to map 347 loci. One hundred and twenty-five loci were localized by physical mapping alone. Of the 222 loci mapped with the ITMI population, 126 were also physically mapped. Considering all mapped loci, 126, 125, and 96 mapped to the A, B, and D genomes, respectively. Twenty-three of the new loci were positioned in gaps larger than 10 cM in the map based on pre-existing markers, and 14 mapped to the ends of chromosomes. The length of the linkage map was extended by 80.7 cM. Map positions were consistent for 111 of the 126 loci positioned by both genetic and physical mapping. The majority of the 15 discrepancies between genetic and physical mapping involved chromosome group 5.

Base Sequence↗
PubMed2005

Molecular cytogenetic characterization of rearrangements involving 12p in leukemia.

Translocations involving the short arm of chromosome 12 are frequent events among patients with various hematologic malignancies. In approximately half of these patients, fluorescence in situ hybridization (FISH) analysis has shown that the breakpoints are clustered within the ETS-variant gene 6 (ETV6) at 12p13, leading to its fusion with a variety of partner genes on different chromosomes. The remaining patients have breakpoints centromeric or telomeric to ETV6 or, less frequently, interstitial 12p13 deletions that invariably involve this gene. In most cases reported, 12p translocations were found to be associated with other structural and/or numerical abnormalities as part of a complex karyotype. Initially using conventional cytogenetic analysis, we characterized the chromosomal breakpoints of three leukemia patients (two with B-acute lymphoblastic leukemia and one with myelodysplastic/myeloproliferative disorder) presenting a t(5;12)(q13;p13), t(12;15)(p13;q22), and dic(9;12)(p11;p11), respectively, as the only structural abnormalities in the karyotype. These rearrangements were further investigated using FISH and molecular studies. Two cases revealed cryptic three-way translocations that had gone undetected in the conventional cytogenetic analyses. One of the cases presented an ETV6 rearrangement with an unsuspected fusion, with the CBFA2 gene at 21q22. In the other two, small and large 12p deletions that included ETV6 were found. This report illustrates the chromosomal and molecular heterogeneity of rearrangements underlying 12p chromosome translocations in leukemia.

Aged↗
PubMed2004

Circulating cell-free fetal DNA in maternal serum appears to originate from cyto- and syncytio-trophoblastic cells. Case report.

Circulating cell-free fetal DNA in maternal serum offers an early and non-invasive method for prenatal diagnosis, but the origin of this DNA is still unknown. We report the absence of the SRY gene in maternal serum of a pregnant woman despite male genitalia at ultrasound. The karyotype was 45,X after direct trophoblast analysis and 45,X/46,Xidic(Yp) after culture and in all fetal tissues studied. Due to the absence of the SRY sequence in maternal blood and in the cytotrophoblast, we presume that free fetal DNA in this case originates from trophoblastic cells. As the case presented here is exceptional, it only has a minor impact on the accuracy of fetal sex determination by maternal serum analysis, but highlights the importance of and the necessity for the complementary ultrasonographic control.

DNA↗
PubMed2004

Spontaneous resolution of a Chiari I malformation associated syringomyelia in one child.

A child with complete spontaneous resolution of a Chiari I malformation associated Syringomyelia without surgical intervention is presented. The child was followed clinically by serial magnetic resonance imaging (MRI) and remains neurologically stable after 8-years of follow-up. To our knowledge, only 6 pediatric cases with spontaneous resolution of a spinal cord syrinx documented by MRI without surgical intervention have been reported. This case is of interest in the light of the postulated theories to explain spontaneous resolution of syringomyelia.

Arnold-Chiari Malformation↗
PubMed2004

[Occipital dermal sinus associated to a cerebellar abscess. Case].

Congenital dermal sinuses are tubular tracts which communicate the skin with deeper structures. It is a manifestation of defective separation of the ectoderm and neuroderm. The incidence is 1/2500-3000 births alive. Almost 10 % of congenital dermal sinuses are localized in the occipitocervical region. They are usually asymptomatic, unless an infectious process is concurrent (meningitis, abscess). We are presenting the case of a 12 months girl with unnoticed cutaneous stigmata in the occipital region, who was admitted with a meningeal syndrome and secondary neurological impairment. She had a cerebellar abscess and was treated with decompression by puncture of the abscess and antibiotics. When infection was resolved, congenital dermal sinus was excised. Process solves without morbidity. We reviewed the clinical and therapeutic features in cases reported previously in the literature.

Cerebellum↗
PubMed2003

[Contribution of genotyping for fetal sex determination in maternal serum for preimplantation genetic diagnosis of X-linked diseases].

OBJECTIVE: Couples with a risk of transmitting X-linked diseases included in a preimplantation genetic diagnosis (PGD) center need early and rapid fetal sex determination during pregnancy in two situations. The first situation corresponds to control of embryo sexing after PGD, the second one being that of couples in PGD program having a spontaneous pregnancy. Determination of fetal sex can be achieved by karyotyping using invasive procedures such as chorionic villus sampling (CVS), amniocentesis or cordocentesis and by non-invasive procedures such as ultrasound (US) examination. CVS is the earliest invasive procedure for fetal sex determination and molecular analysis of X-linked genetic disorders during the first trimester but it is associated with a risk of fetal loss. US allows reliable fetal sex determination only during the second trimester. Recently, reliable non-invasive fetal sex determination was realized by using SRY gene amplification in maternal serum. PATIENTS AND METHODS: We report the prospective use of fetal sex determination in maternal serum in our PGD center. Management of pregnancies was performed using this non-invasive procedure in four cases of embryo sexing control and nine cases of spontaneous pregnancies in couples included in PGD program for X-linked diseases. RESULTS: Fetal sex results using SRY gene amplification on maternal serum were in complete concordance with fetal sex observed by cytogenetic analysis or US examination, as well as at birth. DISCUSSION AND CONCLUSION: This new strategy allowed rapid sex determination during the first trimester and permitted to avoid performing invasive procedures in nine pregnancies.

Adult↗
PubMed2003

Mutational spectrum and DNA-based prenatal diagnosis in carnitine-acylcarnitine translocase deficiency.

Carnitine-acylcarnitine translocase (CAC) deficiency is a rare autosomal recessive disorder of long-chain fatty acid oxidation with a severe outcome. We report mutation analysis in a cohort of 12 patients. Twelve mutations were identified of which 9 have not been reported so far (G28C, D32N, R178Q, P230R, D231H, 179delG, 802delG, 69-70insTGTGC, and 609-1g>a). Altogether, including our results, 22 mutations of the CAC gene have been published to date in 23 patients demonstrating the allelic heterogeneity of CAC deficiency. DNA-based prenatal diagnosis was performed for the first time in pregnancies at risk for CAC deficiency. Two fetuses were affected and one pregnancy was terminated by family decision. Two other fetuses had normal genotype and five others were heterozygotes. All the offspring of these seven pregnancies are alive and apparently healthy.

Amniotic Fluid↗
PubMed2003

[Growing skull fracture in childhood. Presentation of 12 cases].

Growing skull fractures (GSF) are rare complications of head injury (HI) in childhood. This entity consists of a skull fracture with an underlying dural tear that courses with a progressive enlargement of the fracture to produce a cranial defect. The pathophysiology and some aspects of its management are still controversial. In this review we present 12 patients diagnosedd and treated for a GSF at our institution between 1980 and 2002. 11 patients were under the age of 3 years and one patient was 5 years old at the moment of HI. The most common cause of injury was a fall from height. In the initial plain x-rayfilms, 11 patients showed a diastatic skull fracture and one patient only had a linear fracture. At this time, CT scan showed cortical contussion underlying the fracture in every case. The mean time between injury and presentation of GSF was 11.6 weeks. Diagnosis was made by palpation of the cranial defect and confirmed with skull x-rayfilms. The most frecuent location of GSF was in the parietal region. Associated lesions like hydrocephalus, encephalomalacia, lepto-menigeal cysts, brain tissue herniation and ipsilateral ventricular dilatation, were found in the preoperative CT or MRI. All patients underwent a dural repair with pericranium or fascia lata. The cranial defect was covered with local calvarial bone fragments in every case. Only one patient needed a cranioplasty with titanium mesh. Every child with a skull fracture must be followed until the fracture heals. Patients under the age of 3 years with a diastatic fracture and a dural tear, demostrated by TC or MRI, are more prone to develop GSF. In these cases, early repair must be adviced in order to prevent progressive brain damage.

Child, Preschool↗
PubMed2002

[Unusual abdominal complication of ventriculoperitoneal shunt].

The most common complications after CSF shunting to treat hydrocephalus are shunt infection and obstruction. Although ventriculoperitoneal (VP) diversion of the CSF using artificial shunt devices is an accepted method for the management of hydrocephalus, high rates of various complications have been reported, ranging from 24% to 47%. Among these, abdominal complications account for approximately 25%. The incidence of bowel perforation by shunt-catheter is known to be as low as 0.1-0.7%. We describe a case of migration af a peritoneal catheter through a congenital hernia of Morgagni.

Child↗
PubMed2002

[First trimester fetal sex determination in maternal serum using real-time PCR].

OBJECTIVE: Fetal sex prediction can be achieved using PCR targeted at the SRY gene by analyzing cell-free fetal DNA in maternal serum. Unfortunately, the results reported to date, show lack of sensitivity, especially in the first trimester of pregnancy. Therefore, determination of fetal sex by maternal serum analysis can not replace caryotype analysis following chorionic villus sampling. PATIENTS AND METHODS: A new highly sensitive real-time PCR was developed to detect a SRY gene sequence in maternal serum. Analysis was performed on 121 pregnant women during their first trimester of pregnancy (mean gestational age: 11.8 weeks). Among them, 61 had at least one previous male-bearing pregnancy. Results were compared to fetal sex. RESULTS: SRY PCR analysis of maternal serum was in complete concordance with fetal sex. Among the 121 pregnant women, 61 were bearing a male fetus and 60 a female fetus No false negative results were observed. Furthermore, no false positive results results occurred although 27 women carried female fetus during the current pregnancy, had at least one previous male-bearing pregnancy. DISCUSSION AND CONCLUSION: This study demonstrates that a reliable, non-invasive sex determination can be achieved by PCR analysis of maternal serum during the first trimester of pregnancy. This non-invasive approach for fetal sex prediction should have great implications in the management of pregnant women carriers of an X-linked genetic disorder. Prenatal diagnosis is thus performed for male fetuses only, avoiding invasive procedures and the risk of fetal loss for female fetuses.

DNA↗
PubMed2001

Prenatal diagnosis of congenital toxoplasmosis by duplex real-time PCR using fluorescence resonance energy transfer hybridization probes.

The diagnosis of congenital toxoplasmosis frequently relies on PCR tests of amniotic fluid (AF). A duplex real-time quantitative PCR test based on fluorescence resonance energy transfer was developed to quantify the parasite load and to decrease the risk of contamination. An internal control based on the detection of 10 pg mouse DNA added to the AF was included to check for PCR efficiency. The relationship between the parasite load and the occurrence of ultrasonographic abnormalities in 87 samples of AF was analyzed. Seven AF (8%) had a parasitic load > 10(3); 14 (16%) had > 10(2)-< or =10(3); 26 (30%) had > 10-< or = 10(2); and 40 (46%) had < or = 10 parasites/ml. Four of the six AF with cerebral ventriculomegaly had >10(3) parasites/ml. The other two had 130 and 24 parasites/ml, respectively. No parasitic loads of > 10(3) parasites/ml and no ultrasonographic abnormalities were observed in the 11 AF with maternal toxoplasmosis in the third trimester. Therefore, there is a trend to associate high parasite count with ultrasonographic abnormality, but the main concern remains early maternal infection. The importance of quantification should be better evaluated with postnatal studies. The duplex LightCycler PCR test currently provides rapid and safe results.

Amniocentesis↗
PubMed2001

First-trimester fetal sex determination in maternal serum using real-time PCR.

Fetal sex prediction can be achieved using PCR targeted at the SRY gene by analysing cell-free fetal DNA in maternal serum. Unfortunately, the results reported to date show a lack of sensitivity, especially during the first trimester of pregnancy. Therefore, determination of fetal sex by maternal serum analysis could not replace karyotype analysis following chorionic villus sampling. A new highly sensitive real-time PCR was developed to detect an SRY gene sequence in maternal serum. Analysis was performed on 121 pregnant women during the first trimester of pregnancy (mean gestational age: 11.8 weeks). Among them, 51 had at least one previous male-bearing pregnancy. Results were compared with fetal sex. SRY PCR analysis of maternal serum was in complete concordance with fetal sex. Among the 121 pregnant women, 61 were bearing a male fetus and 60 a female fetus. No false-negative results were observed. Furthermore, no false-positive results occurred, even though 27 women carrying a female fetus during the current pregnancy had at least one previous male-bearing pregnancy. This study demonstrates that a reliable, non-invasive sex determination can be achieved by PCR analysis of maternal serum during the first trimester of pregnancy. This non-invasive approach for fetal sex prediction should have great implications in the management of pregnant women who are carriers of an X-linked genetic disorder. Prenatal diagnosis might thus be performed for male fetuses only, avoiding invasive procedures and the risk of the loss of female fetuses.

DNA↗
PubMed2001

Pott's puffy tumour: still not an eradicated entity.

Pott's puffy tumour is an infrequent entity characterised by one or more subperiosteal abscesses associated with frontal bone osteomyelitis. Although cases in patients of all ages have been reported, teenagers are the most frequently affected. Early diagnosis and aggressive treatment are essential because of the high risk of severe neurological complications, such as epidural abscess, subdural empyema, and secondary septic thrombosis of the dural sinuses. This paper describes the case of a patient with a subperiosteal abscess resulting from sinusitis, with orbital and intracranial extension, and subsequent neurological complications. Despite modern methods of diagnosis and treatment, 13 new cases have been published in the last 5 years; in at least 3 (23%) of these cases there were serious neurological complications. Upper respiratory infections and sinusitis are leading causes of visits to the emergency department in the paediatric age group; however, no risk factors for poor outcome have so far been identified in any of these patients.

Abscess↗
PubMed2001

First isolation of Candida dubliniensis in Rio Grande do Sul, Brazil.

Candida dubliniensis is a newly recognized species closely phylogenetically related to Candida albicans and is commonly associated with oral candidiasis in human immunodeficiency virus-positive patients. In this paper we report the isolation of three strains of C. dubliniensis, from AIDS patients, in the state of Rio Grande do Sul (Brazil). The phenotypic identification was based on germ tube emission, abundant production of chlamydospores, assimilation of sucrose but not of xylose and the inability to grow at 42 degrees C. Randomly amplified polymorphic DNA (RAPD) analysis and genomic DNA sequencing confirmed the distinct genetic nature C. dubliniensis. Topics related to the epidemiology, isolation, phenotypical and genotypical identification of C. dubliniensis are also discussed.

AIDS-Related Opportunistic Infections↗
PubMed2001

Galactomannan and polymerase chain reaction for the diagnosis of primary digestive aspergillosis in a patient with acute myeloid leukaemia.

Primary intestinal invasive aspergillosis is rarely reported in leukaemic patients. We describe a case of jejunal invasive aspergillosis in the setting of aplasia following chemotherapy for acute myeloid leukaemia. The diagnosis was confirmed by biopsy obtained during surgery and our polymerase chain reaction (PCR) test confirmed Aspergillus flavus as the fungus responsible. This patient had high levels of circulating galactomannan, an antigen secreted by Aspergillus sp., in serum. The ELISA test for galactomannan has been developed to improve the diagnosis of invasive aspergillosis but presents a 5-15% false positive rate. We suggest that some false positive results might be due to non-respiratory invasive aspergillosis, the usual localization of invasive aspergillosis. Our PCR test was also positive in serum. In case of positive results in serum with antigen and/or PCR tests without respiratory symptoms, the intestinal localizations should be investigated.

Aspergillosis↗
PubMed2001

Sandflies (Diptera: Psychodidae) of the Amazônia of Maranhão. V. Seasonal occurrence in ancient colonization area and endemic for cutaneous leishmaniasis.

In this paper, the seasonal abundance of 25 sandfly species (1 of the Brumptomyia genus and 24 of the Lutzomyia genus) found at P1V5, municipal district of Buriticupu, Maranhão State, is discussed. The capture was carried out from 18:00 P.M. to 6:00 A.M., once a month, from January to December 1996. CDC light traps were set up in the forest, in the peri and intradomicile environments. Five species were only found in the rainy season (January to June), being represented by one or two individuals; eight species occurred only in the dry season (July to December) and eleven species appeared in both seasons. The most frequent species in the dry period were: L. whitmani (26.3%), L. serrana (23%), L. choti (22.8%), L. evandroi (7.5%), L. longipalpis (5.8%), L. termitophila (3.3%), L. shannoni (3%) and L. migonei (2.5%). In the rainy season, L. whitmani was the prevailing species (74%), followed by L. termitophila (4%), L. umbratilis (3.4%), L. serrana (2.8%), L. evandroi (2,8%) and L. claustrei (2.4%). L. whitmani was thought to be an annual species, occurring in the entire year of study. The others species, with exception to L. serrana and L. evandroi, showed a seasonal, punctual or peripheric pattern.

Animals↗