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1.
Heredity (Edinb) ; 89(6): 488-94, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12466993

RESUMO

Interspecific triploid hybrid plants between the tetraploid species Coffea arabica L. and the diploid species C. canephora P. were backcrossed to C. arabica. Although characterised by a low production and an important fruit dropping, all attempted crosses (ie, 6) generated BC(1) progenies. Flow cytometric analysis of the nuclear DNA content revealed that most of the BC1 individuals were nearly tetraploid. Among the male gametes produced by the interspecific triploid hybrids, those presenting a high number of chromosomes appeared strongly favoured. Only pollen mother cells having nearly 22 chromosomes were effective, the others leading to deficient endosperm and fruit dropping. Molecular markers (ie, microsatellite and AFLP) combined with evaluations of morphological characteristics and resistance to leaf rust were applied to verify the occurrence of gene transfer from C. canephora into C. arabica, and to estimate the amount of introgression present in BC(1) individuals. The results reveal a strong deficiency in the C. canephroa alleles indicating a severe counter-selection against the introgression of genetic material from C. canephora into C. arabica by way of triploid hybrids. However, introgressants displaying desirable traits such as a high resistance to leaf rust were obtained. The low level of introgression could be an advantage by facilitating the recovery of the recurrent parent and possibly reducing the number of required backcrosses. On the other hand, this could be a limitation when attempting the transfer of a complex trait or several simply inherited traits.


Assuntos
Coffea/genética , Hibridização Genética , Poliploidia , DNA/metabolismo , Marcadores Genéticos , Variação Genética , Células Germinativas , Repetições de Microssatélites
2.
Eur J Radiol ; 26(2): 121-31, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9518221

RESUMO

PURPOSE: To determine the frequency, evolution and diagnostic impact of characteristic central nervous system MR imaging lesions in children with neurofibromatosis type 1 (NF1). SUBJECTS: We reviewed 89 children with established or clinically suspected disease. A final diagnosis of NF1 was made in 72 (age range, 10 months to 14 years). RESULTS: Hyperintense lesions on long TR images were detected in 78% of patients, principally involving the basal ganglia, cerebellum and brain stem. In 30% of the globus pallidus lesions, hyperintensity was seen on short TR images, being usually isointense on IR T1 weighted images. Globus pallidus lesions did not enhance. Eight patients presented atypical unenhanced lesions showing either edema, mass effect or hypointensity on short TR images; 2 of them were considered symptomatic brain stem gliomas. Six other children showed one or more growing enhanced cerebral lesions classified as tumors. Other child developed a growing enhanced lesion that markedly decreased in the follow-up studies. Twenty patients (28%) had optic gliomas. In two children, under 6 years old, this tumor appeared de novo. Forty-five children had several follow-up MR imaging studies (mean interval, 3 years). Regression of the basal ganglia lesions, both in size and/or intensity was noticed in 42% of cases, enlargement or new appearance of lesions in 24.5%, mixed increased/decreased in 7%, and stability in 26.5%. White matter lesions of the cerebellum and brain stem decreased in size in 40%, grew in 15.5%, showed a mixed increased/decreased pattern in 11%, and remained unchanged in 33.5% of cases. An involutional tendency of these lesions occurred in children older than 10 years, while progression was more frequent in younger children (P<0.05). CONCLUSIONS: Hyperintense lesions are highly prevalent and characteristic in patients with NF1. MR imaging contributed to a definitive diagnosis of NF1 in 53% of suspected cases. Follow-up studies are necessary in the evaluation of suspected NF1, even if the first examination is negative.


Assuntos
Neoplasias do Sistema Nervoso Central/diagnóstico , Sistema Nervoso Central/patologia , Imageamento por Ressonância Magnética , Neurofibromatose 1/diagnóstico , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino
3.
J Clin Ultrasound ; 26(2): 59-64, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9460631

RESUMO

PURPOSE: This study compares the value of sonography and computed tomography (CT) in assessing fluid-fluid levels (FFLs) in aneurysmal bone cysts (ABCs) in children. METHODS: Five children 4-13 years old with ABC in pubis, humerus, fibula, calcaneus, and ilium-ischium were studied between January 1995 and December 1996. Plain radiography, sonography, and CT were performed. RESULTS: FFLs were visualized equally or better with sonography than with CT. CONCLUSIONS: We propose that sonography be used to complement plain radiography in the prebiopsy assessment of expansile bone lesions with cortical bone thinning because the presence of FFLs is characteristic of ABC. CT and/or magnetic resonance imaging could be used in indeterminate cases and in complex anatomic locations. Such an approach would save time and reduce costs and discomfort to children.


Assuntos
Cistos Ósseos Aneurismáticos/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Adolescente , Criança , Pré-Escolar , Análise Custo-Benefício , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Ultrassonografia
4.
Surg Neurol ; 47(4): 389-91, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9122844

RESUMO

BACKGROUND: Subgaleal abscesses and skull osteomyelitis are very uncommon since the introduction of antibiotics. Eikenella corrodens infection is extremely rare in childhood and has never been reported in calvarial osteomyelitis. METHODS: We present a previously healthy 9-year-old boy, with a history of frontal contusion without injury, who developed E corrodens osteomyelitis of the skull. The radiographic findings are reviewed, including skull films and computed tomographic scans. The patient underwent surgical debridement of the lesion, as well as systemic medical therapy with amoxicillin. We review the medical and surgical therapy for such lesions. The differential diagnosis of a posttraumatic scalp swelling is also reviewed. RESULTS: Good resolution after debridement and antibiotic therapy is reported. CONCLUSIONS: Surgical intervention is emphasized for the removal of bony sequestrum and nonviable bone while maintaining an intact dura.


Assuntos
Eikenella corrodens , Infecções por Bactérias Gram-Negativas/microbiologia , Infecções por Bactérias Gram-Negativas/cirurgia , Osteomielite/microbiologia , Osteomielite/cirurgia , Crânio/microbiologia , Crânio/cirurgia , Criança , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Humanos , Masculino , Osteomielite/tratamento farmacológico
5.
Pediatr Radiol ; 26(9): 680-1, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8781112

RESUMO

We report a case of radial metaphyseal osteochondroma secondary to osteomyelitis in a premature baby of 28 weeks. This is the second case with these characteristics that has been described in the literature. A possible pathogenesis is related to trauma during drainage of the abscess or following the associated inflammatory process.


Assuntos
Neoplasias Ósseas/etiologia , Osteocondroma/etiologia , Osteomielite/complicações , Rádio (Anatomia)/diagnóstico por imagem , Ulna/diagnóstico por imagem , Neoplasias Ósseas/diagnóstico por imagem , Neoplasias Ósseas/patologia , Feminino , Seguimentos , Humanos , Recém-Nascido , Osteocondroma/diagnóstico por imagem , Osteocondroma/patologia , Osteomielite/diagnóstico por imagem , Osteomielite/patologia , Radiografia , Rádio (Anatomia)/patologia , Ulna/patologia
6.
Pediatr Radiol ; 26(7): 488-92, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8662067

RESUMO

A case of neurofibroma of the larynx occurring in generalized neurofibromatosis (von Recklinghausen's disease) is presented, and the previously reported pediatric cases are reviewed. Laryngeal involvement in neurofibromatosis is rare and the predominant signs and symptoms include dyspnea, stridor, loss or change of voice and dysphagia. Problems posed related to diagnosis, management and course of this infrequent laryngeal localization are discussed.


Assuntos
Neoplasias Laríngeas/epidemiologia , Neurofibroma Plexiforme/epidemiologia , Neurofibromatose 1/epidemiologia , Pré-Escolar , Humanos , Neoplasias Laríngeas/diagnóstico por imagem , Masculino , Neurofibroma Plexiforme/diagnóstico por imagem , Neurofibromatose 1/diagnóstico por imagem , Radiografia
7.
Pediatr Radiol ; 25(5): 369-72, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7567267

RESUMO

Three cases of pulmonary plasma cell granuloma in the pediatric age group are presented. Although rare, it is the most frequent primary lung tumor in childhood. In two of the cases, there was a close adherence between the tumor and the surrounding mediastinal structures and diaphragm, a very uncommon feature in these tumors. In the other case, plasma cell granuloma of the lung was seen in association with a clinical-radiological picture of hypertrophic osteoarthropathy, which resolved after excision of the mass. Such an association has not, to date, been reported in the literature, and could constitute an additional finding useful in the differential diagnosis of primary lung tumors in childhood. The literature concerning this issue has been reviewed.


Assuntos
Osteoartropatia Hipertrófica Secundária/complicações , Granuloma de Células Plasmáticas Pulmonar/complicações , Granuloma de Células Plasmáticas Pulmonar/diagnóstico por imagem , Osso e Ossos/diagnóstico por imagem , Criança , Pré-Escolar , Feminino , Humanos , Pulmão/diagnóstico por imagem , Masculino , Osteoartropatia Hipertrófica Secundária/diagnóstico por imagem , Radiografia
8.
AJR Am J Roentgenol ; 158(4): 867-71, 1992 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1546607

RESUMO

Sturge-Weber syndrome is a neurocutaneous syndrome that includes facial and leptomeningeal angiomas. Imaging findings include cerebral lobar atrophy, brain calcifications, choroid plexus enlargement, cranial diploë prominence, and venous abnormalities. We compared the efficacy of CT and MR imaging in making the diagnosis in 14 consecutive patients. CT, with and without contrast enhancement, was performed in all patients, and 11 of the 14 had MR imaging (eight before and after administration of IV gadopentetate dimeglumine). MR imaging was better than CT in showing the extent and degree of brain parenchymal atrophy, the presumed ischemic changes affecting the gray and white matter, and the cranial diploetic prominence on the affected side. MR imaging after contrast administration permitted a better evaluation of the extent and patency of the leptomeningeal angiomatous malformation and the parenchymal venous anomalies. CT was better than MR imaging in showing the presence and extent of cortical calcifications. Enhanced CT and MR imaging were equal in evaluating the prominence of the ipsilateral choroid plexus. Our experience indicates that contrast-enhanced MR imaging is the method of choice in the diagnosis of Sturge-Weber syndrome. Unenhanced CT should be used only if MR findings are normal, to exclude the presence of intracranial calcifications.


Assuntos
Imageamento por Ressonância Magnética , Síndrome de Sturge-Weber/diagnóstico , Tomografia Computadorizada por Raios X , Adolescente , Adulto , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Síndrome de Sturge-Weber/diagnóstico por imagem
9.
Pediatr Radiol ; 22(7): 485-9, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1491903

RESUMO

CT, MRI and neurological features of 27 children with tuberous sclerosis were prospectively compared. Imaging studies were positive in 92.5% of cases. CT was more useful in detecting subependymal nodules, while MRI showed the number and location of cerebral cortical and subcortical lesions more accurately. Cortical lesions in the cerebellar hemispheres were present in 26% of patients. Gadolinium-DTPA used in 10 patients showed slight enhancement of the subependymal lesions in 80% of cases, probably representing active lesions with alteration of the blood-brain barrier. None of the cortical and subcortical lesions enhanced. Giant-cell astrocytomas were detected in 5 patients, the postcontrast CT and MRI studies improving their assessment. Unlike subependymal nodules, all tumors showed marked enhancement regardless of their size. Seizures were present in 96% of patients, mostly beginning before 1 year of age. There was no clear relationship between the radiological features and the neurological evolution of these patients. Therefore, it is not possible to establish a clinical prognosis based on the radiological findings. MRI is the procedure of choice in the diagnosis of tuberous sclerosis. When pre and postcontrast MRI are negative, CT is used to exclude small calcified subependymal nodules. MRI follow-up is required only when tumoral development is clinically suspected.


Assuntos
Astrocitoma/diagnóstico , Neoplasias Encefálicas/diagnóstico , Córtex Cerebelar , Epêndima , Esclerose Tuberosa/diagnóstico , Adolescente , Astrocitoma/complicações , Neoplasias Encefálicas/complicações , Criança , Pré-Escolar , Meios de Contraste , Feminino , Seguimentos , Gadolínio DTPA , Humanos , Lactente , Imageamento por Ressonância Magnética , Masculino , Compostos Organometálicos , Ácido Pentético , Estudos Prospectivos , Tomografia Computadorizada por Raios X , Esclerose Tuberosa/complicações
10.
Gastrointest Radiol ; 17(4): 339-43, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1426851

RESUMO

A total of 158 consecutive therapeutic air enemas were performed upon 133 patients during a 2-year period. Perforation and/or an impairment of the general condition of the children were the only main contraindications for the reduction attempt (five patients). Successful reductions were achieved in 89% of cases with no complications. Operation was performed in all 17 cases of unsuccessful reduction: resection in four cases, easy manual reduction in nine, difficult manual reduction in two, and spontaneous reduction in two. There were 16 (12%) patients with one or more recurrent episodes. In 23 (16%) cases, following pneumatic reduction, a swollen ileocecal valve showing a multiple appearance was observed. This fact sometimes results in a differential diagnosis with incomplete reduction; in all these cases, small bowel aeration was always a sign of complete reduction. No significant difference was noted between a swollen ileocecal valve and patient age, duration of symptoms, presence of small bowel obstruction, and further recurrences. Air enema has improved our previous success obtained with hydrostatic reduction (79%), as well as being a simpler, cleaner, and faster technique for intussusception reduction in children.


Assuntos
Enema , Doenças do Íleo/terapia , Intussuscepção/terapia , Ar , Pré-Escolar , Enema/instrumentação , Feminino , Humanos , Doenças do Íleo/cirurgia , Valva Ileocecal/diagnóstico por imagem , Lactente , Intussuscepção/cirurgia , Masculino , Radiografia , Recidiva
12.
Pediatr Radiol ; 21(6): 389-94, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1749666

RESUMO

CT and MRI were used in a prospective study of the central nervous system (CNS) manifestations in 41 consecutive children with neurofibromatosis type 1 (NF-1). Gadolinium-DTPA was used in 15 patients. MRI was more effective than CT in delimiting the extension of the optic pathway glioma and in evaluating associated cerebral malformations. MRI visualized lesions generally undetected by CT, in the form of iso- or hyperintense foci with respect to the cerebral cortex in T2-weighted sequences. Well-delimited lesions of high signal intensity were observed in the globus pallidus (22 cases), the internal capsule (6 cases), corpus callosum (2 cases), anterior commissure (1 case) and semioval center (2 cases). Poorly defined hyper- or isointense areas were also observed affecting the cerebellar white matter (21 cases) and brain stem (17 cases). None of these lesions showed Gadolinium-DTPA enhancement, and were of no clinical significance. MRI has displaced CT in the initial diagnosis of patients with NF-1. Periodic annual MRI controls are only justified in patients with MRI changes to evaluate the progression or stabilization of the lesions.


Assuntos
Sistema Nervoso Central/patologia , Neurofibromatose 1/diagnóstico , Adolescente , Encefalopatias/complicações , Encefalopatias/diagnóstico , Encefalopatias/diagnóstico por imagem , Sistema Nervoso Central/diagnóstico por imagem , Neoplasias do Sistema Nervoso Central/diagnóstico , Neoplasias do Sistema Nervoso Central/diagnóstico por imagem , Criança , Pré-Escolar , Neoplasias dos Nervos Cranianos/diagnóstico , Neoplasias dos Nervos Cranianos/diagnóstico por imagem , Feminino , Glioma/diagnóstico , Glioma/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Masculino , Neurofibromatose 1/complicações , Neurofibromatose 1/diagnóstico por imagem , Nervo Óptico/diagnóstico por imagem , Nervo Óptico/patologia , Estudos Prospectivos , Tomografia Computadorizada por Raios X
13.
J Urol ; 142(2 Pt 1): 356-7, 1989 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2664222

RESUMO

A case of true complete diphallia associated with multiple malformations is presented. Complete radiological evaluation should include sonography of both penes preoperatively to classify the penile duplication correctly.


Assuntos
Pênis/anormalidades , Ultrassonografia , Anormalidades Múltiplas/diagnóstico , Humanos , Recém-Nascido , Masculino , Escroto/anormalidades
18.
Pediatr Radiol ; 9(2): 111-2, 1980 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7367056

RESUMO

In a newborn infant with heart failure and hepatomegaly the radiological findings suggested hepatic haemangioendothelioma, but subsequently the tumour proved to be a hamartoma.


Assuntos
Hamartoma/congênito , Neoplasias Hepáticas/congênito , Angiografia , Feminino , Hamartoma/diagnóstico por imagem , Humanos , Recém-Nascido , Neoplasias Hepáticas/diagnóstico por imagem
19.
Pediatr Radiol ; 8(3): 188-90, 1979 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-112567

RESUMO

A 2 year old boy with humero-spinal dysostosis is described. This is the third case of this disease reported in the literature. Humero-spinal dysostosis is characterised radiologically by distal humeral bifurcation, elbow subluxation and coronal cleft vertebrae. Congenital, progressive heart disease, possibly with fatal outcome, is probably part of the syndrome.


Assuntos
Úmero/diagnóstico por imagem , Doenças da Coluna Vertebral/diagnóstico por imagem , Doenças Ósseas/diagnóstico por imagem , Pré-Escolar , Diagnóstico Diferencial , Humanos , Lactente , Masculino , Ossificação Heterotópica/diagnóstico por imagem , Radiografia
20.
An Esp Pediatr ; 12(6-7): 501-10, 1979.
Artigo em Espanhol | MEDLINE | ID: mdl-225972

RESUMO

Six primitive hepatic tumours (two benign and four malignant) collected over a period of seven years, are studied. The symptoms were mild or absent in many of the cases, and all were discovered after investigation of hepatomegaly or abdominal mass. The importance of the co-ordinated use of radiological and gammagraphical findings is pointed out.


Assuntos
Carcinoma Hepatocelular/diagnóstico por imagem , Neoplasias Hepáticas/diagnóstico por imagem , Angiografia , Feminino , Humanos , Recém-Nascido , Masculino , Urografia
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