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1.
Ann R Coll Surg Engl ; 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38362748

RESUMO

We present a case of previously unclassified duplicated gallbladder which posed a surgical challenge intraoperatively by mimicking a choledochal cyst. An intraoperative cholangiogram was performed followed by a simple cholecystectomy. No further dissection was performed to avoid bile duct injury and complication from the unconventional anatomy. Postoperative imaging and histology, followed by the second operation confirmed findings consistent with the duplicated gallbladder. Through this case, we have demonstrated the principles of safe cholecystectomy and the importance of a staged approach in an unanticipated encounter of anatomical uncertainty, as well as the description of a new variant of duplicated gallbladder.

2.
BJS Open ; 5(4)2021 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-34426830

RESUMO

BACKGROUND: Limited evidence exists to guide the management of patients with liver metastases from squamous cell carcinoma (SCC). The aim of this retrospective multicentre cohort study was to describe patterns of disease recurrence after liver resection/ablation for SCC liver metastases and factors associated with recurrence-free survival (RFS) and overall survival (OS). METHOD: Members of the European-African Hepato-Pancreato-Biliary Association were invited to include all consecutive patients undergoing liver resection/ablation for SCC liver metastases between 2002 and 2019. Patient, tumour and perioperative characteristics were analysed with regard to RFS and OS. RESULTS: Among the 102 patients included from 24 European centres, 56 patients had anal cancer, and 46 patients had SCC from other origin. RFS in patients with anal cancer and non-anal cancer was 16 and 9 months, respectively (P = 0.134). A positive resection margin significantly influenced RFS for both anal cancer and non-anal cancer liver metastases (hazard ratio 6.82, 95 per cent c.i. 2.40 to 19.35, for the entire cohort). Median survival duration and 5-year OS rate among patients with anal cancer and non-anal cancer were 50 months and 45 per cent and 21 months and 25 per cent, respectively. For the entire cohort, only non-radical resection was associated with worse overall survival (hazard ratio 3.21, 95 per cent c.i. 1.24 to 8.30). CONCLUSION: Liver resection/ablation of liver metastases from SCC can result in long-term survival. Survival was superior in treated patients with liver metastases from anal versus non-anal cancer. A negative resection margin is paramount for acceptable outcome.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Hepáticas , Carcinoma de Células Escamosas/cirurgia , Estudos de Coortes , Humanos , Neoplasias Hepáticas/cirurgia , Recidiva Local de Neoplasia/cirurgia , Estudos Retrospectivos
4.
Haemophilia ; 23(3): e204-e213, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28181366

RESUMO

INTRODUCTION: Inherited defects in RUNX1 are important causes of platelet function disorders. AIM: Our goals were to evaluate RUNX1-related platelet disorders among individuals evaluated for uncharacterized, inherited platelet function disorders and test a proof of concept that bleeding risks could be quantitatively estimated for typical families with an inherited platelet function disorder. METHODS: Index cases with an uncharacterized inherited platelet function disorder were subjected to exome sequencing with confirmation of RUNX1 mutations by Sanger sequencing. Laboratory findings were obtained from medical records and persistence of platelet non-muscle myosin heavy chain IIB (MYH10), a biomarker of RUNX1 defects, was assessed by Western blotting. Bleeding histories were assessed using standardized assessment tools. Bleeding risks were estimated as odds ratios (OR) using questionnaire data for affected individuals compared to controls. RESULTS: Among 12 index cases who had their exomes sequenced, one individual from a family with eight study participants had a c.583dup in RUNX1 that segregated with the disease and was predicted to cause a frameshift and RUNX1 haploinsufficiency. Unlike unaffected family members (n = 2), affected family members (n = 6) had increased bleeding scores and abnormal platelet aggregation and dense granule release responses to agonists but only some had thrombocytopenia and/or dense granule deficiency. This family's mutation was associated with persistence of MYH10 in platelets and increased risks (OR 11-440) for wound healing problems and mild bleeding symptoms, including bleeding interfering with lifestyle in women. CONCLUSION: Inherited platelet dysfunction due to a RUNX1 haploinsufficiency mutation significantly increases bleeding risks.


Assuntos
Transtornos Plaquetários/complicações , Transtornos Plaquetários/genética , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Mutação da Fase de Leitura , Hemorragia/complicações , Fenótipo , Adolescente , Adulto , Idoso , Sequência de Bases , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Linhagem , Risco , Adulto Jovem
5.
Clin Microbiol Infect ; 22(6): 563.e9-563.e17, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26932518

RESUMO

We evaluated single nucleotide polymorphisms (SNPs) associated with infection risk in children with newly diagnosed acute myeloid leukaemia (AML). We conducted a multicentre, prospective cohort study that included children aged ≤18 years with de novo AML. DNA was isolated from blood lymphocytes or buccal swabs, and candidate gene SNP analysis was conducted. Primary outcome was the occurrence of microbiologically documented sterile site infection during chemotherapy. Secondary outcomes were Gram-positive and -negative infections, viridans group streptococcal infection and proven/probable invasive fungal infection. Interpretation was guided by consistency in risk alleles and microbiologic agent with previous literature. Over the study period 254 children and adolescents with AML were enrolled. Overall, 190 (74.8%) had at least one sterile site microbiologically documented infection. Among the 172 with inferred European ancestry and DNA available, nine significant associations were observed; two were consistent with previous literature. Allele A at IL1B (rs16944) was associated with decreased microbiologically documented infection, and allele G at IL10 (rs1800896) was associated with increased risk of Gram-positive infection. We identified SNPs associated with infection risk in paediatric AML. Genotype may provide insight into mechanisms of infection risk that could be used for supportive-care novel treatments.


Assuntos
Doenças Transmissíveis/epidemiologia , Doenças Transmissíveis/genética , Predisposição Genética para Doença , Interleucina-1beta/genética , Leucemia Mieloide Aguda/complicações , Polimorfismo de Nucleotídeo Único , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Estudos Prospectivos , Medição de Risco
6.
Artigo em Inglês | MEDLINE | ID: mdl-26738030

RESUMO

This paper presents and elaborates upon the practicalities of a method which enables the recording of voltage measurements from omental tissue in patients with advanced ovarian cancer. The key components of the proposed low-cost experimental setup are a tungsten electrode, a Ag/AgCl reference electrode and an instrumentation amplifier. Intriguingly, potential difference recordings between cancerous omentum and tissue culture media and between non-cancerous omentum and media, differ for tissue samples coming from the same patient. Further studies are warranted to assess the potential prognostic value of voltage measurements in cancerous tissue.


Assuntos
Eletrodiagnóstico/métodos , Omento/fisiopatologia , Neoplasias Ovarianas/fisiopatologia , Neoplasias Peritoneais/fisiopatologia , Eletrodos , Feminino , Humanos
7.
J Med Econ ; 18(3): 173-88, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25347449

RESUMO

OBJECTIVE: The NeoSphere trial demonstrated that the addition of pertuzumab to trastuzumab and docetaxel for the neoadjuvant treatment of HER2-positive locally advanced, inflammatory, or early breast cancer (eBC) resulted in a significant improvement in pathological complete response (pCR). Furthermore, the TRYPHAENA trial supported the benefit of neoadjuvant dual anti-HER2 therapy. Survival data from these trials is not yet available; however, other studies have demonstrated a correlation between pCR and improved event-free survival (EFS) and overall survival (OS) in this patient population. This study represents the first Canadian cost-effectiveness analysis of pertuzumab in the neoadjuvant treatment of HER2-positive eBC. METHODS: A cost-utility analysis (CUA) was conducted using a three health state Markov model ('event-free', 'relapsed', and 'dead'). Two separate analyses were conducted; the first considering total pCR (ypT0/is ypN0) data from NeoSphere, and the second from TRYPHAENA. Published EFS and OS data partitioned for patients achieving/not achieving pCR were used in combination with the percentage achieving pCR in the pertuzumab trials to estimate survival. This CUA included published utility values and direct medical costs including drugs, treatment administration, management of adverse events, supportive care, and subsequent therapy. To address uncertainty, a probabilistic sensitivity analysis (PSA) and alternative scenarios were explored. RESULTS: Both analyses suggested that the addition of pertuzumab resulted in increased life-years and quality-adjusted life-years (QALYs). The incremental cost per QALY ranged from $25,388 (CAD; NeoSphere analysis) to $46,196 (TRYPHAENA analysis). Sensitivity analyses further support the use of pertuzumab, with cost-effectiveness ratios ranging from $9230-$64,421. At a threshold of $100,000, the addition of pertuzumab was cost-effective in nearly all scenarios (93% NeoSphere; 79% TRYPHAENA). CONCLUSION: Given the improvement in clinical efficacy and a favorable cost per QALY, the addition of pertuzumab in the neoadjuvant setting represents an attractive treatment option for HER2-positive eBC patients.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/economia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Anticorpos Monoclonais Humanizados/economia , Anticorpos Monoclonais Humanizados/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias da Mama/mortalidade , Canadá , Análise Custo-Benefício , Intervalo Livre de Doença , Feminino , Humanos , Cadeias de Markov , Pessoa de Meia-Idade , Terapia Neoadjuvante , Recidiva Local de Neoplasia , Receptor ErbB-2 , Trastuzumab/economia , Trastuzumab/uso terapêutico
8.
Genes Immun ; 15(6): 378-91, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24920533

RESUMO

The 40 Mb T1D susceptibility locus Iddm26 was mapped to chromosome 2 through linkage analysis of a conditioned cross-intercross between the diabetes-prone BBDP and the diabetes-resistant ACI.BBDP-Iddm1,Iddm2 (ACI.1u.Lyp). It is flanked by Iddm32 and Iddm33, which control the kinetics of disease progression. To fine-map Iddm26 and characterize immune phenotypes controlled by this locus, several congenic sublines were generated carrying smaller, overlapping intervals spanning Iddm26 and fragments of Iddm32 and 33. Analysis of disease susceptibility, age of disease onset, and immune phenotypes in these sublines identified subloci regulating these different parameters. Two ACI.1u.Lyp-derived subloci, Iddm26.1 and Iddm26.2, imparted significant protection from diabetes, decreasing the cumulative incidence by as much as 57% and 28%, respectively. Iddm26.2, which overlaps with the human PTPN22 locus, only affected disease susceptibility, whereas Iddm26.1 also significantly affected disease kinetics, delaying T1D onset by more than 10 days compared with the parental BBDP strain. These Iddm26 subloci also regulated various immune phenotypes, including the proportion of splenic macrophages by Iddm26.1, and the proportion of activated T-cells in secondary lymphoid organs by Iddm26.2. The analysis of Iddm26 congenic animals in two different SPF facilities demonstrated that the influence of this locus on T1D is environment-dependent.


Assuntos
Mapeamento Cromossômico/métodos , Cromossomos de Mamíferos , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/imunologia , Animais , Cruzamentos Genéticos , Diabetes Mellitus Tipo 1/sangue , Feminino , Ligação Genética , Loci Gênicos/genética , Loci Gênicos/imunologia , Predisposição Genética para Doença/genética , Imunoglobulina E/sangue , Imunoglobulina E/imunologia , Macrófagos/citologia , Macrófagos/imunologia , Macrófagos/metabolismo , Masculino , Ratos , Ratos Endogâmicos ACI , Ratos Endogâmicos BB , Organismos Livres de Patógenos Específicos , Baço/imunologia , Baço/metabolismo , Análise de Sobrevida , Linfócitos T/citologia , Linfócitos T/imunologia , Linfócitos T/metabolismo , Timócitos/citologia , Timócitos/imunologia , Timócitos/metabolismo
9.
Int Urol Nephrol ; 45(6): 1539-44, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23896941

RESUMO

PURPOSE: Increasing life expectancy and PSA testing has increased the number of men over the age of seventy-five presenting for investigation of potential prostate malignancies. Prostatic biopsies provide diagnostic information; however, they are invasive and may not alter management decisions. Therefore, this study aimed to investigate whether prostate biopsies in this age group were justified. MATERIALS AND METHODS: All men aged 75 years and older who underwent prostatic biopsies between January 2010 and November 2011 at Bedford Hospital were identified and the indication for the biopsies, histopathological results and subsequent management plan investigated. RESULTS: One hundred and thirty-eight (138) prostatic biopsies were undertaken and malignancies identified in 60/138 (43 %) cases. Prebiopsy PSA and examination findings had a poor positive predictive value of 54 %. Fifty-five out of sixty (92 %) cancers were classified as high or medium risk disease with 30/60 (50 %) patients commencing radiotherapy treatment with curative intent. CONCLUSION: In selected patients aged 75 years or over, prostatic biopsies provide important diagnostic information which directly impacts on clinical decisions, supporting their use in this age group.


Assuntos
Tomada de Decisões , Próstata/patologia , Neoplasias da Próstata/patologia , Neoplasias da Próstata/terapia , Fatores Etários , Idoso , Antineoplásicos Hormonais/uso terapêutico , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico , Humanos , Masculino , Gradação de Tumores , Invasividade Neoplásica , Valor Preditivo dos Testes , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/sangue , Conduta Expectante
11.
Curr Oncol ; 19(5): 259-68, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23144574

RESUMO

Most women with advanced breast cancer will develop bone metastases, which are associated with the development of skeletal-related events (sres) such as pathologic fractures and spinal cord compression. This article reviews the evolving definition and incidence of sres, the pathophysiology of bone metastases, and the key evidence for the safety and efficacy of the currently available systemic treatment options for preventing and delaying sres in the setting of breast cancer with bone metastases.The bisphosphonates are structural analogues of endogenous pyrophosphate; three of them (clodronate, pamidronate, and zoledronate) are currently approved for use in Canada in the setting of breast cancer with bone metastases. Denosumab is a fully human immunoglobulin G2 monoclonal antibody that binds to human rankl (receptor activator of nuclear factor κB ligand), thereby preventing osteoclast formation, function, and survival, and reducing cancer-induced destruction of bone. Denosumab has recently been approved in Canada for reducing the risk of sres from the bone metastases associated with a variety of malignancies, including breast cancer. How to predict the patients that will benefit most from prophylactic treatment, the agents to select and the timing of switches between agents, the dosing schedules and durations of treatment to choose, the potential utility of the agents in the adjuvant setting, and the utility of additional endpoints such as markers of bone resorption are among the outstanding questions with respect to the optimal use of antiresorptive agents for patients with breast cancer and bone metastases.

12.
Heredity (Edinb) ; 108(5): 500-6, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22511177

RESUMO

To explore types, levels and patterns of genetic divergence among diploid Gossypium (cotton) genomes, 780 cDNA, genomic DNA and simple sequence repeat (SSR) loci were re-sequenced in Gossypium herbaceum (A1 genome), G. arboreum (A2), G. raimondii (D5), G. trilobum (D8), G. sturtianum (C1) and an outgroup, Gossypioides kirkii. Divergence among these genomes ranged from 7.32 polymorphic base pairs per 100 between G. kirkii and G. herbaceum (A1) to only 1.44 between G. herbaceum (A1) and G. arboreum (A2). SSR loci are least conserved with 12.71 polymorphic base pairs and 3.77 polymorphic sites per 100 base pairs, whereas expressed sequence tags are most conserved with 3.96 polymorphic base pairs and 2.06 sites. SSR loci also exhibit the highest percentage of 'extended polymorphisms' (spanning multiple consecutive nucleotides). The A genome lineage was particularly rapidly evolving, with the D genome also showing accelerated evolution relative to the C genome. Unexpected asymmetry in mutation rates was found, with much more transition than transversion mutation in the D genome after its divergence from a common ancestor shared with the A genome. This large quantity of orthologous DNA sequence strongly supports a phylogeny in which A-C divergence is more recent than A-D divergence, a subject that is of much importance in view of A-D polyploid formation being key to the evolution of the most productive and finest-quality cottons. Loci that are monomorphic within A or D genome types, but polymorphic between genome types, may be of practical importance for identifying locus-specific DNA markers in tetraploid cottons including leading cultivars.


Assuntos
Evolução Molecular , Genoma de Planta , Gossypium/genética , Filogenia , Diploide , Dosagem de Genes , Gossypium/classificação , Repetições de Microssatélites , Polimorfismo Genético , Poliploidia
13.
Gut ; 60(10): 1317-26, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21478220

RESUMO

BACKGROUND AND AIMS: The incidence of oesophageal adenocarcinoma (OAC) has been increasing rapidly with a dismal survival rate of less than 20%. Understanding the genomic aberrations and biology of this cancer may enhance disease interventions. This study aimed to use genome-wide genomic and expression data to enhance the understanding of OAC pathogenesis and identify groups with differential outcomes. METHODS: Array-comparative genomic hybridisation (aCGH) analysis was carried out on 56 fresh frozen OAC resection samples with long-term clinical follow-up data. Samples with aberrations were further analysed with whole-genome single-nucleotide polymorphism arrays to confirm aCGH findings. Matched gene expression microarray data were used to identify genes with high copy number-expression correlations. Nested-multiplex PCR on DNA from microdissected specimens and fluorescence in situ hybridisation assays were used for target validation. Immunohistochemistry on the same cohort and independent samples (n=371) was used for subsequent validation. Kaplan-Meier survival analyses were performed based on aCGH data after unsupervised K-means clustering (K=5, 50 iterations) and immunohistochemistry data. RESULTS: aCGH identified 17 common regions (>5% samples) of gains and 11 common regions of losses, including novel regions in OAC (loci 11p13 and 21q21.2). Integration of aCGH data with matched gene expression microarray data highlighted genes with high copy number-expression correlations: two deletions (p16/CDKN2A, MBNL1) and four gains (EGFR, WT1, NEIL2, MTMR9). Immunohistochemistry demonstrated protein over-expression of targets with gains: EGFR (10%), WT1 (20%), NEIL2 (14%) and MTMR9 (25%). These targets individually (p<0.060) and in combination had prognostic significance (p=0.008). On the genomic level, K-means clustering identified a cluster (32% of cohort) with differential log(2) ratios of 16 CGH probes (p<4×10(-7)) and a worse prognosis (median survival=1.37 years; p=0.015). CONCLUSIONS: Integration of aCGH and gene expression data identified copy number aberrations and novel genes with prognostic potential in OAC.


Assuntos
Adenocarcinoma/genética , Hibridização Genômica Comparativa/métodos , DNA de Neoplasias/genética , Receptores ErbB/genética , Neoplasias Esofágicas/genética , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica , Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/biossíntese , Biomarcadores Tumorais/genética , Receptores ErbB/biossíntese , Neoplasias Esofágicas/mortalidade , Neoplasias Esofágicas/patologia , Feminino , Seguimentos , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Masculino , Análise em Microsséries , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida , Fatores de Tempo , Reino Unido/epidemiologia
14.
J Cancer Educ ; 25(4): 493-6, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20217291

RESUMO

Breast cancer is the most common cancer diagnosed in women. The present study evaluated the family physicians' (FPs) understanding of adjuvant hormonal therapies for an early breast cancer. FPs were invited to attend teaching workshops on this topic, which utilized a pretest, didactic and interactive teaching, and posttest format. FPs (n = 23) showed an improvement (p < 0.001) in pretest to posttest score. It is clear that, with a targeted teaching, FPs can quickly become more knowledgeable on the topic of hormonal therapies in breast cancer, with the potential of applying this information in their own practice.


Assuntos
Antineoplásicos Hormonais/uso terapêutico , Inibidores da Aromatase/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Educação Médica Continuada , Modelos Educacionais , Médicos de Família/educação , Tamoxifeno/uso terapêutico , Quimioterapia Adjuvante , Competência Clínica , Feminino , Humanos , Pós-Menopausa
15.
Heredity (Edinb) ; 105(5): 463-72, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20160757

RESUMO

After polyploid formation, retention or loss of duplicated genes is not random. Genes with some functional domains are convergently restored to 'singleton' state after many independent genome duplications, and have been referred to as 'duplication-resistant' (DR) genes. To further explore the timeframe for their restoration to the singleton state, 27 cotton homologs of genes found to be 'DR' in Arabidopsis were selected based on diagnostic Pfam domains. Their copy numbers were studied using southern hybridization and sequence analysis in five tetraploid species and their ancestral A and D genome diploids. DR genes had significantly lower copy number than gene families hybridizing to randomly selected cotton ESTs. Three DR genes showed complete loss of D genome-derived homoeologs in some or all tetraploid species. Prior analysis has shown gene loss in polyploid cotton to be rare, and herein only one randomly selected gene showed loss of a homoeolog in only one of the five tetraploid species (Gossypium mustelinum). BAC sequencing confirmed two cases of gene loss in tetraploid cotton. Divergence among 5' sequences of DR genes amplified from G. arboreum, G. raimondii, and Gossypioides kirkii was correlated with gene copy number. These results show that genes containing Pfam domains associated with duplication resistance in Arabidopsis have also been preferentially restored to low copy number after a more recent polyploidization event in cotton. In tetraploid cotton, genes from the progenitor D genome seem to experience more gene copy number divergence than genes from the A genome. Together with D subgenome-biased alterations in gene expression, perhaps gene loss may contribute to the relatively larger portion of quantitative trait variation attributable to D than A subgenome chromosomes of tetraploid cotton.


Assuntos
Evolução Molecular , Dosagem de Genes , Gossypium/genética , Poliploidia , Autorradiografia , Southern Blotting , Etiquetas de Sequências Expressas , Duplicação Gênica , Reação em Cadeia da Polimerase
16.
S Afr Med J ; 99(2): 103-6, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19418671

RESUMO

BACKGROUND: Colorectal carcinoma (CRC) has a low incidence among the black African population. Largely unrecognised in the scientific literature is the fact that a disproportionately large number of young black patients (<50 years old) present with CRC. OBJECTIVES: To analyse those tumours, which we propose may link them to morphological features associated with known genetic pathways. METHODS: A retrospective review of South African patients histologically diagnosed as having CRC by the Division of Anatomical Pathology, National Health Laboratory Service (NHLS) and the University of the Witwatersrand (1732 patients from 1990 to 2003). The histology was fully reviewed in 609 patients (1997-2002), and all specimens from patients <50 years of age were subjected to immunohistochemistry tests for mismatch repair proteins, as well as APC and p53 proteins. RESULTS: Most young patients (<50 years) were black (41% v. 10% white; p < or = 0.001). Blacks had predominantly proximal tumours and significantly more poorly differentiated and/or mucinous tumours (p = 0.006), and loss of mismatch repair protein expression was more evident than in whites. CONCLUSIONS: It seems likely that CRC in young blacks develops through the accumulation of mutations, most probably via mismatch repair deficiency or promoter methylation, which in turn is linked to poor differentiation and a mucinous architecture.


Assuntos
Adenocarcinoma Mucinoso/genética , População Negra/genética , Neoplasias Colorretais/genética , Predisposição Genética para Doença/genética , Proteína 2 Homóloga a MutS/metabolismo , Adenocarcinoma Mucinoso/etnologia , Adenocarcinoma Mucinoso/patologia , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Neoplasias Colorretais/etnologia , Neoplasias Colorretais/patologia , Feminino , Humanos , Masculino , Repetições de Microssatélites/genética , Pessoa de Meia-Idade , Proteína 2 Homóloga a MutS/genética , Razão de Chances , Estudos Retrospectivos , Distribuição por Sexo , População Branca , Adulto Jovem
17.
Heredity (Edinb) ; 103(1): 73-81, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19277058

RESUMO

Whole-genome duplication (polyploidisation) is a widespread mechanism of speciation in plants. Over time, polyploid genomes tend towards a more diploid-like state, through downsizing and loss of duplicated genes (homoeologues), but relatively little is known about the timing of gene loss during polyploid formation and stabilisation. Several studies have also shown gene transcription to be affected by polyploidisation. Here, we examine patterns of gene loss in 10 sets of homoeologues in five natural populations of the allotetraploid Tragopogon miscellus that arose within the past 80 years following independent whole-genome duplication events. We also examine 44 first-generation synthetic allopolyploids of the same species. No cases of homoeologue loss arose in the first allopolyploid generation, but after 80 years, 1.6% of homoeologues were lost in natural populations. For seven homoeologue sets we also examined transcription, finding that 3.4% of retained homoeologues had been silenced in the natural populations, but none in the synthetic plants. The homoeologue losses and silencing events found were not fixed within natural populations and did not form a predictable pattern among populations. We therefore show haphazard loss and silencing of homoeologues, occurring within decades of polyploid formation in T. miscellus, but not in the initial generation.


Assuntos
Deleção de Genes , Inativação Gênica , Poliploidia , Tragopogon/genética , Genes Sintéticos , Genoma de Planta , Dados de Sequência Molecular
18.
J Appl Genet ; 50(1): 17-23, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19193978

RESUMO

Retroviral envelope (env)-like sequences in 2 cultivated allotetraploid cottons and their diploid progenitors have been identified and characterized in this study. DNA sequence analysis reveals that these sequences are heterogeneous. The observed sequence diversity, however, seems to preserve coding information. This is evidenced by the detection of the transmembrane domain (TM), which is the most conserved feature of the divergent retroviral env genes. The high ratio of synonymous to nonsynonymous changes suggests that these sequences are evolving under purifying selection. Phylogenetic analysis shows that Gossypium sequences closely cluster with a lineage of plant endogenous retroviruses that have an env-like gene. These results provide evidence for the antiquity and the wide diversity of env-like sequences in the Gossypium genome.


Assuntos
Gossypium/genética , Gossypium/virologia , Sequência de Aminoácidos , Linhagem da Célula , Análise por Conglomerados , Sequência Conservada , Primers do DNA/genética , Diploide , Produtos do Gene env/genética , Genes de Plantas , Dados de Sequência Molecular , Filogenia , Estrutura Terciária de Proteína , Retroelementos/genética , Retroviridae/genética , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos
19.
J Clin Pathol ; 62(6): 519-24, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19155239

RESUMO

AIMS: In the era of targeted therapeutics, histological typing of hepatobiliary carcinomas has major clinical implications. Little is known about the reproducibility of the pathological diagnosis of primary liver carcinomas. Therefore, this study aimed to evaluate the worldwide variation in the pathological expert diagnoses of primary liver carcinomas with fibrous stroma in patients who did not have cirrhosis. METHODS: A single set of slides was selected from 25 tumours, and this set was reviewed independently by 12 pathologists who have worldwide expertise in liver tumours. Reproducibility of the diagnoses was evaluated by Light's kappa, and diagnoses were clustered by multidimensional scaling. Immunohistochemistry was performed after histological review. RESULTS: The interobserver reproducibility for diagnosis of hepatocellular carcinoma subtypes and cholangiocarcinomas was poor (kappa 0.23-0.52), even when the experts considered that the diagnosis required no additional stains or clinical information. Interestingly, multidimensional scaling revealed three main clusters of tumours: hepatocellular carcinoma with no other specifications (n = 13), fibrolamellar hepatocellular carcinoma (n = 3) and cholangiocarcinoma (n = 9). Using immunohistochemistry, these histological clusters correlated with expression of anti-hepatocyte and anti-cytokeratin 19 (p<0.001). CONCLUSIONS: The results demonstrate the poor reproducibility among experts of the pathological diagnosis of primary liver carcinomas with fibrous stroma in patients who did not have cirrhosis, and highlight that the systematic use of immunohistochemistry may improve the diagnostic accuracy.


Assuntos
Carcinoma Hepatocelular/patologia , Colangiocarcinoma/patologia , Neoplasias Hepáticas/patologia , Oncologia/normas , Adolescente , Adulto , Idoso , Anticorpos/análise , Biomarcadores Tumorais/análise , Antígeno Carcinoembrionário/imunologia , Carcinoma Hepatocelular/química , Criança , Colangiocarcinoma/química , Análise por Conglomerados , Diagnóstico Diferencial , Feminino , Hepatócitos/patologia , Humanos , Imuno-Histoquímica , Queratina-19/imunologia , Queratina-7/imunologia , Queratinas/análise , Neoplasias Hepáticas/química , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Adulto Jovem
20.
Heredity (Edinb) ; 102(3): 266-73, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19002204

RESUMO

What is the fate of organ-specific genes after the organ is lost? For Sorghum propinquum and Sorghum halepense genes that were previously shown to have rhizome-enriched expression, we have conducted comparative analysis of both coding regions and regulatory sequences in Sorghum bicolor (non-rhizomatousness) and S. propinquum (rhizomatousness). Most genes with rhizome-enriched expression appear to have similar numbers of paralogous copies in both genotypes, with only three of 24 genes studied showing significant differences in copy numbers. We detected no greater propensity for mutation in S. bicolor than in S. propinquum of genes with rhizome-enriched expression in the latter. Several cis-acting regulatory elements, particularly an Myb-binding core (AACGG) that is involved in the regulation of the mitotic cyclin, were more abundant in promoters of S. propinquum than in non-rhizomatous S. bicolor or Oryza sativa (rice). We suggest that many genes with rhizome-enriched expression in S. propinquum may serve multiple functions, with partial loss of some of these functions in S. bicolor but ongoing purifying selection acting to preserve the remaining functions. Expressed genes in polyploid S. halepense rhizomes appeared to be more frequently derived from the S. propinquum than the S. bicolor progenitor, but there was some evidence of formation of novel alleles and 'recruitment' of S. bicolor genes to rhizome-enriched expression in S. halepense, suggesting that polyploidy may have offered new evolutionary potential to S. halepense.


Assuntos
Evolução Molecular , Proteínas de Plantas/genética , Rizoma/genética , Sorghum/genética , Dosagem de Genes , Regulação da Expressão Gênica de Plantas , Genótipo , Mutação , Regiões Promotoras Genéticas , Especificidade da Espécie
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