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1.
Sci Rep ; 7(1): 429, 2017 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-28348369

RESUMO

Museum specimens represent valuable genomic resources for understanding host-endosymbiont/parasitoid evolutionary relationships, resolving species complexes and nomenclatural problems. However, museum collections suffer DNA degradation, making them challenging for molecular-based studies. Here, the mitogenomes of a single 1912 Sri Lankan Bemisia emiliae cotype puparium, and of a 1942 Japanese Bemisia puparium are characterised using a Next-Generation Sequencing approach. Whiteflies are small sap-sucking insects including B. tabaci pest species complex. Bemisia emiliae's draft mitogenome showed a high degree of homology with published B. tabaci mitogenomes, and exhibited 98-100% partial mitochondrial DNA Cytochrome Oxidase I (mtCOI) gene identity with the B. tabaci species known as Asia II-7. The partial mtCOI gene of the Japanese specimen shared 99% sequence identity with the Bemisia 'JpL' genetic group. Metagenomic analysis identified bacterial sequences in both Bemisia specimens, while hymenopteran sequences were also identified in the Japanese Bemisia puparium, including complete mtCOI and rRNA genes, and various partial mtDNA genes. At 88-90% mtCOI sequence identity to Aphelinidae wasps, we concluded that the 1942 Bemisia nymph was parasitized by an Eretmocerus parasitoid wasp. Our approach enables the characterisation of genomes and associated metagenomic communities of museum specimens using 1.5 ng gDNA, and to infer historical tritrophic relationships in Bemisia whiteflies.


Assuntos
DNA Mitocondrial/química , DNA Mitocondrial/genética , Fósseis , Hemípteros/genética , Animais , Ásia , Bactérias/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Sequenciamento de Nucleotídeos em Larga Escala , Himenópteros/genética , Metagenômica , Análise de Sequência de DNA , Homologia de Sequência
2.
J Bone Joint Surg Br ; 88(10): 1373-8, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17012430

RESUMO

In order to treat painful subluxation or dislocation secondary to cerebral palsy, 11 patients (12 hips) underwent combined femoral and Chiari pelvic osteotomies with additional soft-tissue releases at a mean age of 14.1 years (9.1 to 17.8). Relief of pain, improvement in movement of the hip, and in sitting posture, and ease of perineal care were recorded in all, and were maintained at a mean follow-up of 13.1 years (8 to 17.5). The improvement in general mobility was marginal, but those who were able to walk benefited the most. The radiological measurements made before operation were modified afterwards to use the lateral margin of the neoacetabulum produced by the pelvic osteotomy. The radiological migration index improved from a mean of 80.6% (61% to 100%) to 13.7% (0% to 33%) (p < 0.0001). The mean changes in centre edge angle and Sharp's angle were 72 degrees (56 degrees to 87 degrees; p < 0.0001) and 12.3 degrees (9 degrees to 15.6 degrees; p < 0.0001), respectively. Radiological evidence of progressive arthritic change was seen in one hip, in which only a partial reduction had been achieved, and there was early narrowing of the joint space in another. Painless heterotopic ossification was observed in one patient with athetoid quadriplegia. In seven hips the lateral Kawamura approach, elevating the greater trochanter, provided exposure for both osteotomies and allowed the construction of a dome-shaped iliac osteotomy, while protecting the sciatic nerve.


Assuntos
Paralisia Cerebral/cirurgia , Luxação do Quadril/cirurgia , Osteotomia/métodos , Adolescente , Paralisia Cerebral/complicações , Paralisia Cerebral/diagnóstico por imagem , Criança , Feminino , Fêmur/diagnóstico por imagem , Fêmur/cirurgia , Luxação do Quadril/diagnóstico por imagem , Luxação do Quadril/etiologia , Articulação do Quadril/diagnóstico por imagem , Articulação do Quadril/cirurgia , Humanos , Masculino , Dor/fisiopatologia , Complicações Pós-Operatórias , Radiografia , Amplitude de Movimento Articular/fisiologia , Escoliose/complicações , Escoliose/cirurgia , Resultado do Tratamento
3.
Hip Int ; 16(3): 185-90, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-19219789

RESUMO

We present a consecutive series of 24 adolescent and young adult patients who have undergone a triple pelvic osteotomy as treatment for symptomatic developmental dysplasia of the hip. With a mean duration of follow-up of 6.5 years (range 2 -16 years) we report good improvements with regard to pain and function in 22 of the 24 patients. Radiological improvements were consistently demonstrated in the centre edge angle and the acetabular index. There were no major complications. When dealing with this difficult problem in young patients we maintain that a redirectional pelvic osteotomy is an appropriate means of treatment in symptomatic patients with a congruent joint.

4.
Arch Dis Child ; 88(12): 1051-5, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14670767

RESUMO

Central core disease (CCD) is a dominantly inherited congenital myopathy allelic to malignant hyperthermia (MH) caused by mutations in the RYR1 gene on chromosome 19q13.1. Eleven individuals with RYR1 mutations are described. Four index cases showed features consistent with a congenital myopathy (hypotonia, delayed motor milestones, and skeletal abnormalities including congenital hip dislocation and scoliosis). All four cases and subsequently seven other family members were found to possess novel mutations in the RYR1 gene. The degree of disability varied from one clinically normal individual, to another who had never achieved independent ambulation (the only patient with a de novo mutation). Four cases showed a mild reduction in vital capacity, repeated nocturnal polysomnography showed hypoxaemia in one case. A variety of muscle biopsy features were found; central cores were absent in the youngest case, and the biopsy specimens from two others were more suggestive of mini-core myopathy. In all cases missense mutations in exons 101, 102, and 103 of the RYR1 gene on were found. Future laboratory diagnosis of suspected cases and family members will be less invasive and more accurate with DNA analysis. Clinicians, especially paediatricians and orthopaedic surgeons, should be aware of this disorder because of the potential risk of MH.


Assuntos
Miopatia da Parte Central , Adolescente , Adulto , Biópsia , Criança , Feminino , Humanos , Lactente , Masculino , Músculo Esquelético/patologia , Mutação/genética , Miopatia da Parte Central/genética , Miopatia da Parte Central/patologia , Linhagem
6.
J Pediatr Orthop B ; 10(3): 248-54, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11497370

RESUMO

Assessing healing after distraction limb lengthening is essential to manage patients undergoing callotasis for leg lengthening or bone transport. Direct measurement of fracture stiffness can assess healing but the equipment may not be available. In addition, it requires removal of the fixator, which may be complicated for ring fixators. The present study investigates whether an equivalent measure of healing can be based on the mineral density pattern from dual-energy X-ray absorptiometry (DXA) scans. Nine consecutive patients undergoing callotasis were studied. Bending stiffness of the distraction segment was measured and DXA scans were performed regularly starting 6 weeks after completing distraction. In all, 23 simultaneous readings of bending stiffness and DXA scans were obtained. All density patterns showed a distinct minimum value of bone mineral density. We found a high and significant correlation between fracture bending stiffness and the square of the total mineral content at the location of minimum bone density (r2 = 0.77, P < 0.001). We conclude that DXA scans can be used reliably and effectively to determine fracture bending stiffness, valuable for determining both time of frame removal and delay in union.


Assuntos
Absorciometria de Fóton/métodos , Densidade Óssea , Alongamento Ósseo/efeitos adversos , Regeneração Óssea , Fêmur , Consolidação da Fratura , Tíbia , Absorciometria de Fóton/instrumentação , Adolescente , Adulto , Fenômenos Biomecânicos , Alongamento Ósseo/métodos , Complacência (Medida de Distensibilidade) , Feminino , Fêmur/anormalidades , Fêmur/diagnóstico por imagem , Fêmur/cirurgia , Humanos , Modelos Lineares , Masculino , Microcomputadores , Pessoa de Meia-Idade , Cintilografia , Tíbia/anormalidades , Tíbia/diagnóstico por imagem , Tíbia/cirurgia , Fatores de Tempo , Resultado do Tratamento
7.
Curr Protoc Hum Genet ; Chapter 5: Unit 5.8, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-18428295

RESUMO

End clones from YACs (terminal fragments of the YAC-insert DNA cloned into a plasmid vector) are essential ingredients for contig building using chromosome walking strategies, for fluorescent in situ hybridization experiments, and for generating repeat-free probes for pulsed-field gel electrophoresis or genetic linkage analysis. The basic protocol describes a method for rescuing the CEN (centromere) ends of YACs constructed in the vector pYAC4. However, because this method relies on XhoI and SalI sites, which are relatively rare in the mammalian genome, it is not always possible to obtain a subclone in this manner. An alternate protocol presents a method utilizing integrative plasmid-rescue vectors to facilitate the isolation of both ends of any YAC clone even in the absence of convenient restriction enzyme sites.


Assuntos
Cromossomos Artificiais de Levedura/genética , Escherichia coli/genética , Plasmídeos/genética , Técnicas Genéticas , Vetores Genéticos , Genética Médica , Humanos
8.
Cancer Res ; 60(23): 6677-82, 2000 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-11118052

RESUMO

Previous functional and deletion mapping studies on cervical cancer (CC) have implicated one or more tumor suppressor genes (TSGs) on chromosome 11 at q13 and q22-24 regions. Of these, the 11q22-24 region exhibits frequent allelic deletions in a variety of solid tumor types, suggesting the presence of critical genes for tumor suppression in this region. However, the precise region of deletion on 11q is not clearly defined in CC. In an attempt to accurately map the deleted region, we performed an extensive loss of heterozygosity (LOH) mapping in 58 tumors using 25 polymorphic loci on both the short and long arms. The pattern of LOH identified three sites of deletions, two on 11p (p15.11-p15.3 and p12-13), and one on 11q (q23.1-q23.2). The 11q23.1-q23.2 exhibited highest frequency (60.6%) of deletions, suggesting that this could be the site of a candidate TSG in CC. The minimal deletion at 11q23.1-23.2 was restricted to a 6-cM region between 123.5 and 129.5 cM genetic distance on chromosome 11, identifying the site of a potential TSG important in the pathogenesis of CC. At least five known genes and 28 UniGene clusters were mapped to the present commonly deleted region. In addition, we have excluded a previously known TSG PPP2R1B at 11q23 as a deletion target in CC. The definition of the minimal deletion and the availability of expressed sequence resources should facilitate the identification of the candidate TSG.


Assuntos
Adenocarcinoma/genética , Carcinoma de Células Escamosas/genética , Cromossomos Humanos Par 11 , Deleção de Genes , Genes Supressores de Tumor/genética , Neoplasias do Colo do Útero/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Mapeamento Cromossômico/métodos , Feminino , Humanos , Perda de Heterozigosidade , Pessoa de Meia-Idade , Mutação , Fosfoproteínas Fosfatases/genética , Polimorfismo Conformacional de Fita Simples
10.
Dev Dyn ; 218(3): 452-64, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10878610

RESUMO

Hereditary multiple exostoses (HME) is a genetically heterogeneous disease characterized by the development of bony protuberances at the ends of all long bones. Genetic analyses have revealed HME to be a multigenic disorder linked to three loci on chromosomes 8q24 (EXT1), 11p11-13 (EXT2), and 19p (EXT3). The EXT1 and EXT2 genes have been cloned and defined as glycosyltransferases involved in the synthesis of heparan sulfate. EST database analysis has demonstrated additional gene family members, EXT-like genes (EXTL1, EXTL2, and EXTL3), not associated with a HME locus. The mouse homologs of EXT1 and EXT2 have also been cloned and shown to be 99% and 95% identical to their human counterparts, respectively. Here, we report the identification of the mouse EXTL1 gene and show it is 74% identical to the human EXTL1 gene. Expression studies of all three mouse EXT genes throughout various stages of embryonic development were carried out and whole-mount in situ hybridization in the developing limb buds showed high levels of expression of all three EXT genes. However, in situ hybridization of sectioned embryos revealed remarkable differences in expression profiles of EXT1, EXT2, and EXTL1. The identical expression patterns found for the EXT1 and EXT2 genes support the recent observation that both proteins form a glycosyltransferase complex. We suggest a model for exostoses formation based on the involvement of EXT1 and EXT2 in the Indian hedgehog/parathyroid hormone-related peptide (PTHrP) signaling pathway, an important regulator of the chondrocyte maturation process.


Assuntos
Desenvolvimento Ósseo/fisiologia , Cartilagem/embriologia , Condrócitos/metabolismo , Exostose Múltipla Hereditária/genética , N-Acetilglucosaminiltransferases , N-Acetilexosaminiltransferases/genética , Proteínas/genética , Proteínas Supressoras de Tumor , Sequência de Aminoácidos , Animais , Sequência de Bases , Northern Blotting , Células COS , Cartilagem/metabolismo , Retículo Endoplasmático/metabolismo , Exostose Múltipla Hereditária/patologia , Expressão Gênica , Perfilação da Expressão Gênica , Humanos , Hibridização In Situ , Camundongos , Modelos Biológicos , Dados de Sequência Molecular , N-Acetilexosaminiltransferases/metabolismo , Reação em Cadeia da Polimerase , Proteínas/metabolismo , Análise de Sequência de DNA
12.
14.
Genes Chromosomes Cancer ; 24(3): 199-206, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10451699

RESUMO

Translocation t(11;21)(q24;q11.2) is a rare but recurrent chromosomal abnormality associated with myelodysplastic syndrome (MDS) that until now has not been characterized at the molecular level. We report here results of a molecular cytogenetic analysis of this translocation in a patient with refractory anemia. Using FISH with a panel of 11q and 21q cosmid/YAC probes, we localized the chromosome 11 breakpoint at q23.3 in a region flanked by CP-921G9 and CP-939H3 YACs, distal to the HRX/MLL locus frequently involved in acute leukemias. The chromosome 21 breakpoint was mapped in a 800-kb fragment inserted into the CP-145E3 YAC at 21q11.2, proximal to the AML1 gene. It is noteworthy that in all four cases with a t(11;21) reported until now, a second der(11)t(11;21) and loss of normal chromosome 11 could be observed either at diagnosis or during the course of the disease. Since in our case heteromorphism was detected by FISH on the centromeric region of the two der(11), the second der(11) chromosome could be the result of a mitotic recombination that had occurred on the long arm of chromosome 11, rather than of duplication of the original der(11). Constancy of secondary karyotypic changes resulting in an extra copy of the putative chimeric gene at der(11), loss of 11 qter sequences, and partial trisomy 21 suggest that neoplastic progression of MDS cases with a t(11;21) may be driven by the same mechanism(s).


Assuntos
Cromossomos Humanos Par 11/genética , Cromossomos Humanos Par 21/genética , Síndromes Mielodisplásicas/genética , Translocação Genética/genética , Bandeamento Cromossômico , Mapeamento Cromossômico , Humanos , Hibridização in Situ Fluorescente , Cariotipagem , Masculino , Pessoa de Meia-Idade
15.
Genes Chromosomes Cancer ; 25(2): 154-9, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10337999

RESUMO

11q23-24 chromosome is a region containing frequent allelic loss (loss of heterozygosity; LOH) in human cancers. To examine cancer-related allelic loss in the region between D11S940 and APOC3, we used 17 polymorphic markers and allotyped 28 lung cancer-derived cell lines and their corresponding matched lymphoblastoid cell lines. LOH was found in 71.4% (20/28) of the lung cancer cell lines and was localized to two distinct minimal regions of loss. One region is bracketed by markers D11S1647 and NCAM2 and contains the gene encoding the beta isoform of the A subunit of the human protein phosphatase 2A (PPP2R1B). Recently, mutations in this gene were described in lung and colon cancers, suggesting that PPP2R1B functions as a tumor-suppressor gene. A second minimal region of loss was defined between markers D11S1792 and D11S1885, a region estimated to be less than I Mb. Thus, chromosome 11 likely harbors two sites of suppressor oncogene activity in lung cancer, one defined by the PPP2R1B gene and the second located telomeric to PPP2R1B. This study facilitates the identification and cloning of a second critical tumor-suppressor gene involved in lung cancer, and possibly a variety of other cancers, on human chromosome band 11q23.


Assuntos
Carcinoma de Células Pequenas/genética , Mapeamento Cromossômico/métodos , Cromossomos Humanos Par 11/genética , Perda de Heterozigosidade/genética , Neoplasias Pulmonares/genética , Genes Supressores de Tumor/genética , Humanos , Repetições de Microssatélites/genética , Células Tumorais Cultivadas
16.
Gene ; 221(1): 135-42, 1998 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-9852958

RESUMO

Here we report the expression of a fork head domain protein in human T helper cells. We cloned and characterized a fork head cDNA from human T helper cell mRNA using differential display RT-PCR. The cDNA contains a 546-nucleotide (nt) open reading frame (ORF) that codes for the carboxyl-terminal 180 amino acids (aa) of the recently identified fkhrl1 gene. This ORF does not contain the characteristic DNA-binding domain found in members of the forkhead protein family. In-vitro transcription/translation of this cDNA expressed a protein of approximately 20 kDa. We have generated antibodies that specifically immunoprecipitated the in-vitro-translated 20-kDa protein. This antibody also recognizes in human T lymphocytes a 70-kDa protein corresponding in size to that predicted for the fkhrl1 gene product. The mRNA levels for fkhrl1 is elevated in T helper-induced lymphocytes in comparison to PHA-stimulated T lymphocytes. Further characterization of FKHRL1 and its related family members should shed light on the transcriptional mechanisms of this fork head gene subfamily and their role in T helper cell differentiation and regulation of cell growth.


Assuntos
Proteínas de Ligação a DNA/genética , Fatores de Transcrição/genética , Sequência de Aminoácidos , Sequência de Bases , Northern Blotting , Diferenciação Celular , Clonagem Molecular , DNA Complementar/química , DNA Complementar/genética , Proteínas de Ligação a DNA/análise , Proteína Forkhead Box O1 , Proteína Forkhead Box O3 , Fatores de Transcrição Forkhead , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Dados de Sequência Molecular , Testes de Precipitina , Biossíntese de Proteínas , RNA Mensageiro/análise , RNA Mensageiro/genética , Alinhamento de Sequência , Análise de Sequência de DNA , Linfócitos T Auxiliares-Indutores/química , Linfócitos T Auxiliares-Indutores/citologia , Linfócitos T Auxiliares-Indutores/metabolismo , Fatores de Transcrição/análise
17.
Mol Biochem Parasitol ; 95(2): 267-80, 1998 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-9803418

RESUMO

The parasitic protozoan Giardia lamblia represents one of the earliest diverging lineages in the evolutionary history of eukaryotic organisms as well as an important human pathogen. A representative sampling of gene sequences from this early diverging protozoan could provide insights into genotypic and phenotypic innovations associated with the origin of eukaryotes. Currently, known giardial gene sequences are heavily biased toward a few gene families, including variant surface proteins (VSPs), structural proteins, and ribosomal RNA genes. One-pass sequences of Giardia genomic DNA were obtained using vector flanking priming sequences on the ends of cosmids in two independent libraries. Comparisons of 2304 of these sequences against the GenBank database identified 205 potential giardial genes with BLAST scores P(n) < 10(9). These coding regions encompass a wide range of metabolic, repair, and signaling enzymes, and include some genes not predicted by our current understanding of Giardia biochemistry. The efficiency of identification of putative genes is consistent with earlier findings that coding regions in the Giardia genome are densely packed and do not appear to contain introns. Our current results suggest that direct genome sequencing is an efficient method for identifying giardial genes for evolutionary and biochemical studies.


Assuntos
Genoma de Protozoário , Giardia lamblia/genética , Análise de Sequência de DNA , Animais , Cosmídeos/genética , Evolução Molecular , Biblioteca Gênica , Genes de Protozoários , Dados de Sequência Molecular , Monoéster Fosfórico Hidrolases/genética , Fosfotransferases/genética , Processamento de Proteína Pós-Traducional , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo
18.
Genomics ; 53(1): 56-68, 1998 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-9787077

RESUMO

Olfactory receptors (OR) are encoded by a large multigene family including hundreds of members dispersed throughout the human genome. Cloning and mapping studies have determined that a large proportion of the olfactory receptor genes are located on human chromosomes 6, 11, and 17, as well as distributed on other chromosomes. In this paper, we describe and characterize the organization of olfactory receptor genes on human chromosome 11 by using degenerate PCR-based probes to screen chromosome 11-specific and whole genome clone libraries for members of the OR gene family. OR genes were identified by DNA sequencing and then localized to regions of chromosome 11. Physical maps of several gene clusters were constructed to determine the chromosomal relationships between various members of the family. This work identified 25 new OR genes located on chromosome 11 in at least seven distinct regions. Three of these regions contain gene clusters that include additional members of this gene family not yet identified by sequencing. Phylogenetic analysis of the newly described OR genes suggests a mechanism for the generation of genetic diversity.


Assuntos
Cromossomos Humanos Par 11/genética , Receptores Odorantes/genética , Sequência de Aminoácidos , Mapeamento Cromossômico , Clonagem Molecular , Sondas de DNA/genética , Humanos , Dados de Sequência Molecular , Filogenia , Mapeamento Físico do Cromossomo , Alinhamento de Sequência , Análise de Sequência de DNA
19.
Arch Neurol ; 55(10): 1287-90, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9779654

RESUMO

The Human Genome Project (HGP), an international program to decode the entire DNA sequence of the human genome in 15 years, represents the largest biological experiment ever conducted. This set of information will contain the blueprint for the construction and operation of a human being. While the primary driving force behind the genome project is the potential to vastly expand the amount of genetic information available for biomedical research, the ramifications for other fields of study in biological research, the biotechnology and pharmaceutical industry, our understanding of evolution, effects on agriculture, and implications for bioethics are likely to be profound.


Assuntos
Encefalopatias/genética , Projeto Genoma Humano , Encefalopatias/diagnóstico , Encefalopatias/terapia , Clonagem Molecular , DNA Bacteriano/genética , Biblioteca Genômica , Humanos , Neurociências
20.
Science ; 282(5387): 284-7, 1998 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-9765152

RESUMO

The PPP2R1B gene, which encodes the beta isoform of the A subunit of the serine/threonine protein phosphatase 2A (PP2A), was identified as a putative human tumor suppressor gene. Sequencing of the PPP2R1B gene, located on human chromosome 11q22-24, revealed somatic alterations in 15% (5 out of 33) of primary lung tumors, 6% (4 out of 70) of lung tumor-derived cell lines, and 15% (2 out of 13) of primary colon tumors. One deletion mutation generated a truncated PP2A-Abeta protein that was unable to bind to the catalytic subunit of the PP2A holoenzyme. The PP2R1B gene product may suppress tumor development through its role in cell cycle regulation and cellular growth control.


Assuntos
Neoplasias do Colo/genética , Genes Supressores de Tumor , Neoplasias Pulmonares/genética , Fosfoproteínas Fosfatases/genética , Sequência de Aminoácidos , Ciclo Celular , Divisão Celular , Mapeamento Cromossômico , Cromossomos Humanos Par 11/genética , Neoplasias do Colo/enzimologia , Mutação da Fase de Leitura , Humanos , Perda de Heterozigosidade , Neoplasias Pulmonares/enzimologia , Dados de Sequência Molecular , Fosfoproteínas Fosfatases/química , Fosfoproteínas Fosfatases/metabolismo , Mutação Puntual , Proteína Fosfatase 2 , Deleção de Sequência , Células Tumorais Cultivadas
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