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1.
Blood Coagul Fibrinolysis ; 34(4): 247-249, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36966757

RESUMO

Purpura fulminans is a thrombotic emergency affecting small vessels of skin and of internal organs that may rapidly progress into necrotizing fasciitis, critical limb ischaemia and multiorgan failure; it often develops during an infection or as a postinfective 'autoimmune' disorder. Although supportive care and hydration are important, anticoagulation ought to be started to prevent further occlusions alongside blood products according to need. Herein, we describe the case of an elderly woman who received extended intravenous low-dose recombinant tissue plasminogen activator at the onset of purpura fulminans that salvaged her skin and prevented the development of multiorgan failure.


Assuntos
Púrpura Fulminante , Trombose , Humanos , Feminino , Idoso , Púrpura Fulminante/tratamento farmacológico , Púrpura Fulminante/etiologia , Ativador de Plasminogênio Tecidual/uso terapêutico , Insuficiência de Múltiplos Órgãos
2.
Prev Med ; 145: 106410, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33388329

RESUMO

One in five U.S. women with health insurance are underscreened for cervical cancer. We sought to identify whether underscreening correlates differed among women with different levels of health care interaction. Among women age 30-64 years who were members of an integrated U.S. health system, we used 2014-2015 electronic health record data to identify underscreened cases (≥3.4 years since last Papanicolaou (Pap) test, n=3352) and screening-adherent controls (<3.4 years since last Pap test, n=45,359) and extracted data on potential underscreening correlates (demographics, health history, and healthcare utilization). We calculated the odds of underscreening in the total population and by subgroups defined by healthcare visits and online health portal usage in the prior 12 months. Underscreening was associated with older age (50-64 vs. 30-39; odds ratio (OR)=1.6; 95%CI=1.4-1.8), current tobacco use (vs. never use; OR=2.1; 95%CI=1.8-2.2), higher BMI (≥35 kg/m2 vs <25 kg/m2, OR=2.0; 95%CI=1.8-2.3), screening non-adherence for colorectal cancer (OR=5.1; 95%CI=4.6-5.7) and breast cancer (OR=8.1, 95%CI=7.2-9.0), and having no recent visit with their primary care provider (PCP) nor recent health portal use (vs. recent PCP visit and portal use; OR=8.4, 95%CI=7.6-9.4). Underscreening correlates were similar between the total study population and within all healthcare interaction groups. Interaction with the healthcare system is associated with lower odds of underscreening, but sociodemographic and health status correlates are similar regardless of primary care visits or online portal use. These data support the need for additional interventions to reach insured women who remain underscreened for cervical cancer.


Assuntos
Prestação Integrada de Cuidados de Saúde , Neoplasias do Colo do Útero , Adulto , Idoso , Detecção Precoce de Câncer , Feminino , Humanos , Pessoa de Meia-Idade , Teste de Papanicolaou , Estados Unidos , Neoplasias do Colo do Útero/diagnóstico , Esfregaço Vaginal
4.
Prev Med ; 132: 105953, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31911163

RESUMO

HPV self-sampling (HPV-SS) can increase cervical cancer screening participation by addressing barriers in high- and low- and middle-income settings. Successful implementation of HPV-SS programs will depend on understanding potential costs and health effects. Our objectives were to summarize the methods and results of published HPV-SS cost and cost-effectiveness studies, present implications of these results for HPV-SS program implementation, and identify knowledge gaps. We followed the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines. One reviewer searched online databases for articles published through June 12, 2019, identified eligible studies, and extracted data; a second reviewer checked extracted data for accuracy. Eligible studies used an economic model to compare HPV-SS outreach strategies to standard-of-care tests. Of 16 eligible studies, 14 reported HPV-SS could be a cost-effective strategy. Studies differed in model type, HPV-SS delivery methods, triage strategies for positive results, and target populations. Most (9/16) modeled HPV-SS in European screening programs, 6/16 targeted women who were underscreened for cervical cancer, and 5/16 modeled HPV-SS in low- and middle-income countries. The most commonly identified driver of HPV-SS cost-effectiveness was the level of increase in cervical cancer screening attendance. Lower HPV-SS material and testing costs, higher sensitivity to detect cervical precancer, and longer duration of underscreening among HPV-SS users were also associated with increased cost-effectiveness. Future HPV-SS models in high-income settings should explore the effect of widespread vaccination and new triage strategies such as partial HPV genotyping. Knowledge gaps remain about the cost-effectiveness of HPV-SS in low- and middle-income settings.


Assuntos
Análise Custo-Benefício , Detecção Precoce de Câncer/economia , Infecções por Papillomavirus/prevenção & controle , Adulto , Alphapapillomavirus/isolamento & purificação , Países em Desenvolvimento , Europa (Continente) , Feminino , Humanos , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/prevenção & controle
5.
J Med Screen ; 27(3): 146-156, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-31744374

RESUMO

OBJECTIVES: To evaluate experiences and reactions after receiving a mailed, unsolicited human papillomavirus self-sampling kit and identify psychosocial correlates of using kits. METHODS: Survey participants were underscreened women aged 30-64 who were mailed human papillomavirus kits as part of a pragmatic trial at Kaiser Permanente Washington, a United States integrated health care system. Six months after the mailing, we invited kit returners and non-returners to complete a web survey that measured psychosocial factors (e.g. cervical cancer/human papillomavirus knowledge, attitudes toward screening), experiences, and reactions to kits. We compared responses between kit returners and non-returners. RESULTS: Comparing 116 kit returners (272 invited) and 119 non-returners (1083 invited), we found no clinically significant differences in psychosocial factors. Overall, survey respondents showed knowledge gaps in human papillomavirus natural history (82% did not know human papillomavirus infection can clear on its own) and interpreting human papillomavirus test results (37% did not know a human papillomavirus-negative result indicates low cancer risk). Kit returners found kits convenient and easy to use (>90%). The most common reason for non-return was low confidence in ability to correctly use a kit, although many non-returners (49%) indicated that they would consider future use. Women reported low trust in human papillomavirus testing to identify women at high risk for cervical cancer (52% in returners, 42% in non-returners). CONCLUSIONS: Screening programs could improve uptake and acceptability of human papillomavirus self-sampling through outreach materials that emphasize the high efficacy of human papillomavirus testing for cervical cancer screening and educate patients about how to interpret results.


Assuntos
Alphapapillomavirus/isolamento & purificação , Atitude Frente a Saúde , Detecção Precoce de Câncer/métodos , Infecções por Papillomavirus/diagnóstico , Autoteste , Neoplasias do Colo do Útero/diagnóstico , Adulto , Feminino , Promoção da Saúde/métodos , Humanos , Pessoa de Meia-Idade , Serviços Postais , Manejo de Espécimes/métodos , Inquéritos e Questionários , Neoplasias do Colo do Útero/virologia , Esfregaço Vaginal
6.
Lancet ; 393(10173): 758-767, 2019 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-30712878

RESUMO

BACKGROUND: Identification of chromosomal aneuploidies and copy number variants that are associated with fetal structural anomalies has substantial value. Although whole-exome sequencing (WES) has been applied to case series of a few selected prenatal cases, its value in routine clinical settings has not been prospectively assessed in a large unselected cohort of fetuses with structural anomalies. We therefore aimed to determine the incremental diagnostic yield (ie, the added value) of WES following uninformative results of standard investigations with karyotype testing and chromosomal microarray in an unselected cohort of sequential pregnancies showing fetal structural anomalies. METHODS: In this prospective cohort study, the parents of fetuses who were found to have a structural anomaly in a prenatal ultrasound were screened for possible participation in the study. These participants were predominantly identified in or were referred to the Columbia University Carmen and John Thain Center for Prenatal Pediatrics (New York, NY, USA). Fetuses with confirmed aneuploidy or a causal pathogenic copy number variant were excluded from WES analyses. By use of WES of the fetuses and parents (parent-fetus trios), we identified genetic variants that indicated an underlying cause (diagnostic genetic variants) and genetic variants that met the criteria of bioinformatic signatures that had previously been described to be significantly enriched among diagnostic genetic variants. FINDINGS: Between April 24, 2015, and April 19, 2017, 517 sequentially identified pregnant women found to have fetuses with a structural anomaly were screened for their eligibility for inclusion in our study. 71 (14%) couples declined testing, 87 (17%) trios were missing at least one DNA sample (from either parent or the fetus), 69 (13%) trios had a clinically relevant abnormal karyotype or chromosomal microarray finding, 51 (10%) couples did not consent to WES or withdrew consent, and five (1%) samples were not of good enough quality for analysis. DNA samples from 234 (45%) eligible trios were therefore used for analysis of the primary outcome. By use of trio sequence data, we identified diagnostic genetic variants in 24 (10%) families. Mutations with bioinformatic signatures that were indicative of pathogenicity but with insufficient evidence to be considered diagnostic were also evaluated; 46 (20%) of the 234 fetuses assessed were found to have such signatures. INTERPRETATION: Our analysis of WES data in a prospective cohort of unselected fetuses with structural anomalies shows the value added by WES following the use of routine genetic tests. Our findings suggest that, in cases of fetal anomalies in which assessment with karyotype testing and chromosomal microarray fail to determine the underlying cause of a structural anomaly, WES can add clinically relevant information that could assist current management of a pregnancy. The unique challenges of WES-based prenatal diagnostics require analysis by a multidisciplinary team of perinatal practitioners and laboratory specialists. FUNDING: Institute for Genomic Medicine (Columbia University Irving Medical Center).


Assuntos
Cariótipo Anormal/embriologia , Anormalidades Múltiplas/diagnóstico , Anormalidades Múltiplas/genética , Aneuploidia , Variações do Número de Cópias de DNA/genética , Sequenciamento do Exoma/estatística & dados numéricos , Desenvolvimento Fetal/genética , Feto/anormalidades , Anormalidades Múltiplas/epidemiologia , Amniocentese , Amostra da Vilosidade Coriônica , Feminino , Triagem de Portadores Genéticos , Humanos , Masculino , Gravidez , Estudos Prospectivos , Ultrassonografia Pré-Natal , Sequenciamento do Exoma/métodos
7.
J Womens Health (Larchmt) ; 28(3): 384-392, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30481121

RESUMO

OBJECTIVE: We explored patient perspectives after a positive human papillomavirus (HPV) self-sampling result to describe experiences and information needs for this home-based screening modality. MATERIALS AND METHODS: We recruited women who tested high-risk (hr) HPV positive during a pragmatic trial evaluating mailed hrHPV self-sampling kits as an outreach strategy for women overdue for Pap screening in a U.S. integrated health care system. Telephone interviews were conducted from 2014 to 2017. Five independent coders analyzed transcripts using iterative content analysis. RESULTS: Forty-six women (61% of invited; median age 55.5 years) completed a semistructured interview. Six themes emerged: (1) convenience of home-based screening, (2) intense feelings and emotions after receiving positive kit results, (3) importance of seeing provider and discussing kit results, (4) information seeking from various sources, (5) confusion about purpose and meaning of HPV versus Pap tests, and (6) concern that HPV self-sampling is inaccurate when the subsequent Pap test is normal. CONCLUSIONS: Although women liked the kit's convenience, discussion about discordant home HPV and in-clinic Pap results led them to question the accuracy of HPV self-sampling. Patient-provider communication around home HPV kits is more complex than for reflex or cotesting because clinician-collected Pap results are unknown at the time of the positive kit result. Patients need education about differences between HPV and Pap tests and how they are used for screening and follow-up. To reassure patients and keep them interested in self-sampling, education should be provided at multiple time points during the screening process.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Teste de Papanicolaou/métodos , Infecções por Papillomavirus/diagnóstico , Autoexame , Neoplasias do Colo do Útero/diagnóstico , Adulto , Detecção Precoce de Câncer/métodos , Feminino , Humanos , Programas de Rastreamento/métodos , Pessoa de Meia-Idade , Papillomaviridae/isolamento & purificação , Educação de Pacientes como Assunto/métodos
8.
N Engl J Med ; 380(2): 142-151, 2019 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-30586318

RESUMO

BACKGROUND: Exome sequencing is emerging as a first-line diagnostic method in some clinical disciplines, but its usefulness has yet to be examined for most constitutional disorders in adults, including chronic kidney disease, which affects more than 1 in 10 persons globally. METHODS: We conducted exome sequencing and diagnostic analysis in two cohorts totaling 3315 patients with chronic kidney disease. We assessed the diagnostic yield and, among the patients for whom detailed clinical data were available, the clinical implications of diagnostic and other medically relevant findings. RESULTS: In all, 3037 patients (91.6%) were over 21 years of age, and 1179 (35.6%) were of self-identified non-European ancestry. We detected diagnostic variants in 307 of the 3315 patients (9.3%), encompassing 66 different monogenic disorders. Of the disorders detected, 39 (59%) were found in only a single patient. Diagnostic variants were detected across all clinically defined categories, including congenital or cystic renal disease (127 of 531 patients [23.9%]) and nephropathy of unknown origin (48 of 281 patients [17.1%]). Of the 2187 patients assessed, 34 (1.6%) had genetic findings for medically actionable disorders that, although unrelated to their nephropathy, would also lead to subspecialty referral and inform renal management. CONCLUSIONS: Exome sequencing in a combined cohort of more than 3000 patients with chronic kidney disease yielded a genetic diagnosis in just under 10% of cases. (Funded by the National Institutes of Health and others.).


Assuntos
Exoma , Predisposição Genética para Doença , Mutação , Insuficiência Renal Crônica/genética , Análise de Sequência de DNA/métodos , Adulto , Idoso , Estudos de Coortes , Variação Genética , Humanos , Masculino , Pessoa de Meia-Idade , Insuficiência Renal Crônica/etnologia , Adulto Jovem
9.
Ann Neurol ; 83(6): 1133-1146, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29679388

RESUMO

OBJECTIVE: Somatic variants are a recognized cause of epilepsy-associated focal malformations of cortical development (MCD). We hypothesized that somatic variants may underlie a wider range of focal epilepsy, including nonlesional focal epilepsy (NLFE). Through genetic analysis of brain tissue, we evaluated the role of somatic variation in focal epilepsy with and without MCD. METHODS: We identified somatic variants through high-depth exome and ultra-high-depth candidate gene sequencing of DNA from epilepsy surgery specimens and leukocytes from 18 individuals with NLFE and 38 with focal MCD. RESULTS: We observed somatic variants in 5 cases in SLC35A2, a gene associated with glycosylation defects and rare X-linked epileptic encephalopathies. Nonsynonymous variants in SLC35A2 were detected in resected brain, and absent from leukocytes, in 3 of 18 individuals (17%) with NLFE, 1 female and 2 males, with variant allele frequencies (VAFs) in brain-derived DNA of 2 to 14%. Pathologic evaluation revealed focal cortical dysplasia type Ia (FCD1a) in 2 of the 3 NLFE cases. In the MCD cohort, nonsynonymous variants in SCL35A2 were detected in the brains of 2 males with intractable epilepsy, developmental delay, and magnetic resonance imaging suggesting FCD, with VAFs of 19 to 53%; Evidence for FCD was not observed in either brain tissue specimen. INTERPRETATION: We report somatic variants in SLC35A2 as an explanation for a substantial fraction of NLFE, a largely unexplained condition, as well as focal MCD, previously shown to result from somatic mutation but until now only in PI3K-AKT-mTOR pathway genes. Collectively, our findings suggest a larger role than previously recognized for glycosylation defects in the intractable epilepsies. Ann Neurol 2018.


Assuntos
Encéfalo/patologia , Epilepsia Resistente a Medicamentos/genética , Proteínas de Transporte de Monossacarídeos/genética , Neocórtex/patologia , Adolescente , Criança , Exoma/genética , Feminino , Humanos , Masculino , Malformações do Desenvolvimento Cortical/genética , Mutação/genética , Neurônios/patologia , Fosfatidilinositol 3-Quinases/genética , Serina-Treonina Quinases TOR/genética , Adulto Jovem
10.
Nature ; 552(7684): 268-272, 2017 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-29211718

RESUMO

Transposable elements can drive genome evolution, but their enhanced activity is detrimental to the host and therefore must be tightly regulated. The Piwi-interacting small RNA (piRNA) pathway is vital for the regulation of transposable elements, by inducing transcriptional silencing or post-transcriptional decay of mRNAs. Here we show that piRNAs and piRNA biogenesis components regulate precursor mRNA splicing of P-transposable element transcripts in vivo, leading to the production of the non-transposase-encoding mature mRNA isoform in Drosophila germ cells. Unexpectedly, we show that the piRNA pathway components do not act to reduce transcript levels of the P-element transposon during P-M hybrid dysgenesis, a syndrome that affects germline development in Drosophila. Instead, splicing regulation is mechanistically achieved together with piRNA-mediated changes to repressive chromatin states, and relies on the function of the Piwi-piRNA complex proteins Asterix (also known as Gtsf1) and Panoramix (Silencio), as well as Heterochromatin protein 1a (HP1a; encoded by Su(var)205). Furthermore, we show that this machinery, together with the piRNA Flamenco cluster, not only controls the accumulation of Gypsy retrotransposon transcripts but also regulates the splicing of Gypsy mRNAs in cultured ovarian somatic cells, a process required for the production of infectious particles that can lead to heritable transposition events. Our findings identify splicing regulation as a new role and essential function for the Piwi pathway in protecting the genome against transposon mobility, and provide a model system for studying the role of chromatin structure in modulating alternative splicing during development.


Assuntos
Processamento Alternativo , Elementos de DNA Transponíveis/genética , Drosophila melanogaster/citologia , Drosophila melanogaster/genética , Células Germinativas/metabolismo , RNA Interferente Pequeno/genética , Animais , Proteínas Argonautas/metabolismo , Cromatina/química , Cromatina/genética , Cromatina/metabolismo , Homólogo 5 da Proteína Cromobox , Proteínas Cromossômicas não Histona/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/enzimologia , Feminino , Células Germinativas/citologia , Masculino , Proteínas Nucleares/metabolismo , Ovário/citologia , Ovário/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/metabolismo , Retroelementos/genética
11.
JMM Case Rep ; 4(3): jmmcr005087, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28663821

RESUMO

Introduction.Staphylococcus pseudintermedius, an opportunistic pathogen of dogs and cats, is rarely reported to cause infection in humans. Here, we describe a case of severe skin infection caused by S. pseudintermedius, in a 47-year-old male, a dog owner; to the best of our knowledge, this is the first such case reported from Scotland. Case presentation. The patient presented with a short history of a severe ecthyma-like lesion on his forehead, with smaller lesions on his abdomen and legs. Bacterial culture revealed Clostridium perfringens, thought to be colonizing the wound, and a Staphylococcus species, identified as S. pseudintermedius by matrix-assisted laser desorption/ionization-time of flight MS and confirmed by molecular methods using a PCR-RFLP approach. The patient was treated with flucloxacillin, penicillin V and Fucibet cream, and recovered fully. Zoonotic infection was considered likely; however, screening swabs from his dogs grew S. pseudintermedius of a different clonal type. Both patient and dog strains carried Staphylococcus intermedius exfoliative toxin and leucocidin I, closely related to Panton-Valentine leucocidin, possibly contributing to the severity of the infection. S pseudintermedius, although coagulase positive, is normally negative by rapid slide clumping and latex agglutination tests routinely used to identify Staphylococcus aureus. Hence, S. pseudintermedius may easily be misidentified as a coagulase-negative staphylococcus and considered insignificant. Conclusion. This is, to the best of our knowledge, the first reported case of a human S. pseudintermedius infection in Scotland. Zoonotic transmission of S. pseudintermedius between pets and owners has been shown. However, in this case zoonosis could not be confirmed.

12.
Am J Respir Crit Care Med ; 196(1): 82-93, 2017 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-28099038

RESUMO

RATIONALE: Idiopathic pulmonary fibrosis (IPF) is an increasingly recognized, often fatal lung disease of unknown etiology. OBJECTIVES: The aim of this study was to use whole-exome sequencing to improve understanding of the genetic architecture of pulmonary fibrosis. METHODS: We performed a case-control exome-wide collapsing analysis including 262 unrelated individuals with pulmonary fibrosis clinically classified as IPF according to American Thoracic Society/European Respiratory Society/Japanese Respiratory Society/Latin American Thoracic Association guidelines (81.3%), usual interstitial pneumonia secondary to autoimmune conditions (11.5%), or fibrosing nonspecific interstitial pneumonia (7.2%). The majority (87%) of case subjects reported no family history of pulmonary fibrosis. MEASUREMENTS AND MAIN RESULTS: We searched 18,668 protein-coding genes for an excess of rare deleterious genetic variation using whole-exome sequence data from 262 case subjects with pulmonary fibrosis and 4,141 control subjects drawn from among a set of individuals of European ancestry. Comparing genetic variation across 18,668 protein-coding genes, we found a study-wide significant (P < 4.5 × 10-7) case enrichment of qualifying variants in TERT, RTEL1, and PARN. A model qualifying ultrarare, deleterious, nonsynonymous variants implicated TERT and RTEL1, and a model specifically qualifying loss-of-function variants implicated RTEL1 and PARN. A subanalysis of 186 case subjects with sporadic IPF confirmed TERT, RTEL1, and PARN as study-wide significant contributors to sporadic IPF. Collectively, 11.3% of case subjects with sporadic IPF carried a qualifying variant in one of these three genes compared with the 0.3% carrier rate observed among control subjects (odds ratio, 47.7; 95% confidence interval, 21.5-111.6; P = 5.5 × 10-22). CONCLUSIONS: We identified TERT, RTEL1, and PARN-three telomere-related genes previously implicated in familial pulmonary fibrosis-as significant contributors to sporadic IPF. These results support the idea that telomere dysfunction is involved in IPF pathogenesis.


Assuntos
Exoma/genética , Predisposição Genética para Doença/genética , Fibrose Pulmonar Idiopática/genética , Feminino , Variação Genética/genética , Humanos , Masculino , Pessoa de Meia-Idade
13.
Cell Stem Cell ; 18(2): 276-90, 2016 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-26669894

RESUMO

Complex regulatory networks regulate stem cell behavior and contributions to tissue growth, repair, and homeostasis. A full understanding of the networks controlling stem cell self-renewal and differentiation, however, has not yet been realized. To systematically dissect these networks and identify their components, we performed an unbiased, transcriptome-wide in vivo RNAi screen in female Drosophila germline stem cells (GSCs). Based on characterized cellular defects, we classified 646 identified genes into phenotypic and functional groups and unveiled a comprehensive set of networks regulating GSC maintenance, survival, and differentiation. This analysis revealed an unexpected role for ribosomal assembly factors in controlling stem cell cytokinesis. Moreover, our data show that the transition from self-renewal to differentiation relies on enhanced ribosome biogenesis accompanied by increased protein synthesis. Collectively, these results detail the extensive genetic networks that control stem cell homeostasis and highlight the intricate regulation of protein synthesis during differentiation.


Assuntos
Diferenciação Celular , Drosophila melanogaster/citologia , Células Germinativas/citologia , Biogênese de Organelas , Biossíntese de Proteínas , Ribossomos/metabolismo , Células-Tronco/citologia , Animais , Nucléolo Celular/patologia , Sobrevivência Celular/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Fator de Iniciação 4E em Eucariotos/metabolismo , Regulação da Expressão Gênica , Técnicas de Silenciamento de Genes , Genes de Insetos , Hipertrofia , Iniciação Traducional da Cadeia Peptídica/genética , Fenótipo , Ligação Proteica , Interferência de RNA , Transcriptoma/genética
14.
Curr Opin Genet Dev ; 34: 88-94, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26451497

RESUMO

During normal tissue development, the accumulation of unrepaired cellular and genomic damage can impair growth and ultimately leads to death. To preserve cellular integrity, cells employ a number of defense mechanisms including molecular checkpoints, during which development is halted while dedicated pathways attempt repair. This process is most critical in germline tissues where cellular damage directly threatens an organism's reproductive capacity and offspring viability. In the fruit fly, Drosophila melanogaster, germline development has been extensively studied for over a century and the breadth of our knowledge has flourished in the genomics age. Intriguingly, several peculiar phenomena that trigger catastrophic germline damage described decades ago, still endure only a partial understanding of the underlying molecular causes. A deeper reexamination using new molecular and genetic tools may greatly benefit our understanding of host system biology. Among these, and the focus of this concise review, are hybrid dysgenesis and an intragenomic conflict that pits the X and Y sex chromosomes against each other.


Assuntos
Proteínas de Drosophila/genética , Drosophila melanogaster/crescimento & desenvolvimento , Células Germinativas/crescimento & desenvolvimento , Disgenesia Gonadal/genética , Proteínas Quinases/genética , Animais , Drosophila melanogaster/genética , Células Germinativas/metabolismo , Células Germinativas/patologia , Disgenesia Gonadal/patologia , Cromossomos Sexuais/genética , Biologia de Sistemas
15.
J Neuroinflammation ; 12: 134, 2015 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-26186920

RESUMO

BACKGROUND: Rasmussen encephalitis (RE) is a rare neuroinflammatory disease characterized by intractable seizures and progressive atrophy on one side of the cerebrum. Perivascular cuffing and clusters of T cells in the affected cortical hemisphere are indicative of an active cellular immune response. METHODS: Peripheral blood mononuclear cells (PBMCs) and brain-infiltrating lymphocytes (BILs) were isolated from 20 RE surgery specimens by standard methods, and CD3(+) T cell populations were analyzed by flow cytometry. Gamma delta T cell receptor spectratyping was carried out by nested PCR of reversed transcribed RNA extracted from RE brain tissue, followed by high resolution capillary electrophoresis. A MiSeq DNA sequencing platform was used to sequence the third complementarity determining region (CDR3) of δ1 chains. RESULTS: CD3(+) BILs from all of the RE brain specimens comprised both αß and γδ T cells. The median αß:γδ ratio was 1.9 (range 0.58-5.2) compared with a median ratio of 7.7 (range 2.7-40.8) in peripheral blood from the same patients. The αß T cells isolated from brain tissue were predominantly CD8(+), and the majority of γδ T cells were CD4(-) CD8(-). Staining for the early activation marker CD69 showed that a fraction of the αß and γδ T cells in the BILs were activated (median 42%; range 13-91%, and median 47%; range 14-99%, respectively). Spectratyping T cell receptor (TCR) Vδ1-3 chains from 14 of the RE brain tissue specimens indicated that the γδ T cell repertoire was relatively restricted. Sequencing δ1 chain PCR fragments revealed that the same prevalent CDR3 sequences were found in all of the brain specimens. These CDR3 sequences were also detected in brain tissue from 15 focal cortical dysplasia (FCD) cases. CONCLUSION: Neuroinflammation in RE involves both activated αß and γδ T cells. The presence of γδ T cells with identical TCR δ1 chain CDR3 sequences in all of the brain specimens examined suggests that a non-major histocompatibility complex (MHC)-restricted immune response to the same antigen(s) is involved in the etiology of RE. The presence of the same δ1 clones in CD brain implies the involvement of a common inflammatory pathway in both diseases.


Assuntos
Encefalite/imunologia , Encefalite/fisiopatologia , Imunidade Celular/fisiologia , Receptores de Antígenos de Linfócitos T gama-delta/fisiologia , Linfócitos T/fisiologia , Antígenos CD/imunologia , Antígenos CD/fisiologia , Antígenos de Diferenciação de Linfócitos T/imunologia , Antígenos de Diferenciação de Linfócitos T/fisiologia , Encéfalo/imunologia , Encéfalo/patologia , Encéfalo/fisiopatologia , Criança , Pré-Escolar , Estudos de Coortes , Regiões Determinantes de Complementaridade/imunologia , Regiões Determinantes de Complementaridade/fisiologia , Encefalite/patologia , Epilepsia/imunologia , Epilepsia/patologia , Epilepsia/fisiopatologia , Feminino , Humanos , Imunidade Celular/imunologia , Lactente , Lectinas Tipo C/imunologia , Lectinas Tipo C/fisiologia , Masculino , Malformações do Desenvolvimento Cortical do Grupo I/imunologia , Malformações do Desenvolvimento Cortical do Grupo I/patologia , Malformações do Desenvolvimento Cortical do Grupo I/fisiopatologia , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/fisiologia , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Linfócitos T/imunologia , Linfócitos T/patologia
16.
J Vis Exp ; (96)2015 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-25741775

RESUMO

We report a novel adaptation of the Radial Monolayer Cell Migration assay, first reported to measure the radial migration of adherent tumor cells on extracellular matrix proteins, for measuring the motility of fluorescently-labeled, non-adherent human or murine effector immune cells. This technique employs a stainless steel manifold and 10-well Teflon slide to focally deposit non-adherent T cells into wells prepared with either confluent tumor cell monolayers or extracellular matrix proteins. Light and/or multi-channel fluorescence microscopy is used to track the movement and behavior of the effector cells over time. Fluorescent dyes and/or viral vectors that code for fluorescent transgenes are used to differentially label the cell types for imaging. This method is distinct from similar-type in vitro assays that track horizontal or vertical migration/invasion utilizing slide chambers, agar or transwell plates. The assay allows detailed imaging data to be collected with different cell types distinguished by specific fluorescent markers; even specific subpopulations of cells (i.e., transduced/nontransduced) can be monitored. Surface intensity fluorescence plots are generated using specific fluorescence channels that correspond to the migrating cell type. This allows for better visualization of the non-adherent immune cell mobility at specific times. It is possible to gather evidence of other effector cell functions, such as cytotoxicity or transfer of viral vectors from effector to target cells, as well. Thus, the method allows researchers to microscopically document cell-to-cell interactions of differentially-labeled, non-adherent with adherent cells of various types. Such information may be especially relevant in the assessment of biologically-manipulated or activated immune cell types, where visual proof of functionality is desired with tumor target cells before their use for cancer therapy.


Assuntos
Movimento Celular/fisiologia , Linfócitos T Citotóxicos/fisiologia , Animais , Neoplasias da Mama/imunologia , Neoplasias da Mama/patologia , Adesão Celular/fisiologia , Comunicação Celular/fisiologia , Linhagem Celular Tumoral , Feminino , Corantes Fluorescentes , Vetores Genéticos , Proteínas de Fluorescência Verde/biossíntese , Proteínas de Fluorescência Verde/química , Proteínas de Fluorescência Verde/genética , Humanos , Teste de Cultura Mista de Linfócitos , Camundongos , Microscopia de Fluorescência , Retroviridae/genética , Linfócitos T Citotóxicos/citologia , Transdução Genética , Transgenes
17.
Genes Dev ; 28(16): 1786-99, 2014 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-25104425

RESUMO

The exon junction complex (EJC) is a highly conserved ribonucleoprotein complex that binds RNAs during splicing and remains associated with them following export to the cytoplasm. While the role of this complex in mRNA localization, translation, and degradation has been well characterized, its mechanism of action in splicing a subset of Drosophila and human transcripts remains to be elucidated. Here, we describe a novel function for the EJC and its splicing subunit, RnpS1, in preventing transposon accumulation in both Drosophila germline and surrounding somatic follicle cells. This function is mediated specifically through the control of piwi transcript splicing, where, in the absence of RnpS1, the fourth intron of piwi is retained. This intron contains a weak polypyrimidine tract that is sufficient to confer dependence on RnpS1. Finally, we demonstrate that RnpS1-dependent removal of this intron requires splicing of the flanking introns, suggesting a model in which the EJC facilitates the splicing of weak introns following its initial deposition at adjacent exon junctions. These data demonstrate a novel role for the EJC in regulating piwi intron excision and provide a mechanism for its function during splicing.


Assuntos
Proteínas Argonautas/metabolismo , Elementos de DNA Transponíveis/fisiologia , Proteínas de Drosophila/metabolismo , Drosophila/genética , Drosophila/metabolismo , Splicing de RNA , Ribonucleoproteínas/metabolismo , Animais , Proteínas Argonautas/genética , DNA Complementar/metabolismo , Proteínas de Drosophila/genética , Feminino , Técnicas de Silenciamento de Genes , Inativação Gênica , Íntrons/genética , Mutação , Ovário/citologia , Ovário/metabolismo , Subunidades Proteicas/metabolismo , Ribonucleoproteínas/genética
18.
Arch Pathol Lab Med ; 138(6): 803-8, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24878019

RESUMO

CONTEXT: The creation of 3-dimensional prostate cancer maps could assist with surgical intervention, radiotherapy treatment planning and for correlative pathology-imaging research. OBJECTIVES: To develop methodology for creating detailed, 3-dimensional, prostate cancer maps (3DPCM) of tumor location, extra prostatic extension sites, and positive margins and to assess the adequacy of current clinical target volumes for postoperative radiotherapy to the prostate using 3DPCM coregistered with preoperative magnetic resonance imaging. DESIGN: Parallel slices of prostatectomy specimens were created with ProCUT, and 2-dimensional cancer maps were generated as line diagrams after microscopic examination of each slice. The 2-dimensional cancer maps were aligned and stacked to create a 3DPCM, which was coregistered with the preoperative magnetic resonance imaging scan. The map was exported to the radiotherapy planning system and was used to determine the areas at greater risk, which were then compared against the current Radiation Therapy Oncology Group guidelines for contouring postoperative clinical target volumes to assess the adequacy of coverage. RESULTS: Twenty-eight patients with a mean age of 66 years (range, 52-73) underwent radical prostatectomy and postoperative radiotherapy. Seventeen patients (61%) received adjuvant radiotherapy for pT3 disease and/or positive margins, and the rest underwent salvage radiotherapy. Thirty-nine percent (11 of 28) of the patients had Gleason scores of 8 or 9. The contours based on the Radiation Therapy Oncology Group guidelines for postoperative radiotherapy resulted in inadequate coverage of extraprostatic extensions in 79% (22 of 28) and positive margins in 64% (18 of 28) of the cases. CONCLUSIONS: We have developed a methodology for creation of 3DPCM. Modification of the radiotherapy contours, based on the 3DPCM coregistered with pretreatment magnetic resonance imaging, covers the areas at high risk of recurrence. The 3DPCM could become an important clinical and research tool for urologists, pathologists, radiologists, and oncologists.


Assuntos
Imageamento Tridimensional/métodos , Neoplasias da Próstata/patologia , Idoso , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Prostatectomia , Neoplasias da Próstata/radioterapia , Neoplasias da Próstata/cirurgia , Planejamento da Radioterapia Assistida por Computador
19.
Can J Urol ; 20(5): 6944-9, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24128835

RESUMO

INTRODUCTION: Stereotactic ablative body radiotherapy (SABR) is currently under study regarding its clinical application in management of patients with kidney tumors. CyberKnife can accurately deliver ablative tumor radiation doses while preserving kidney function. We report Canada's first use of CyberKnife SABR system in treating primary kidney tumors. MATERIALS AND METHODS: Between January 2011 and February 2012, we treated three patients with renal tumors using CyberKnife SABR. Two patients had tumors in solitary kidney. The third patient had a recurrent tumor after two previous radiofrequency ablation treatments. Platinum seed fiducials were used for real time tumor tracking. Magnetic resonance imaging registration was used for tumor delineation in all cases. The patients were followed with regular renal scans and renal function tests. RESULTS: The mean age was 79 years. Mean tumor size was 21.3 cm3. A dose of 39 Gy in 3 fractions was delivered. The post treatment follow up times were 15 months, 13 months and 12 months. Local control was obtained in all three patients. No acute or chronic toxicity was reported. Kidney functions remained unaffected after treatment. CONCLUSION: CyberKnife is technically feasible for treatment of medically inoperable renal tumors or tumors in a solitary kidney.


Assuntos
Carcinoma de Células Renais/cirurgia , Carcinoma de Células de Transição/cirurgia , Neoplasias Renais/cirurgia , Radiocirurgia , Idoso , Idoso de 80 Anos ou mais , Canadá , Carcinoma de Células Renais/patologia , Carcinoma de Células Renais/fisiopatologia , Carcinoma de Células de Transição/patologia , Carcinoma de Células de Transição/fisiopatologia , Seguimentos , Humanos , Rim/patologia , Rim/fisiopatologia , Rim/cirurgia , Neoplasias Renais/patologia , Neoplasias Renais/fisiopatologia , Imageamento por Ressonância Magnética , Estudos Retrospectivos , Resultado do Tratamento
20.
RNA ; 19(8): 1064-77, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23788724

RESUMO

Piwi proteins and their associated small RNAs are essential for fertility in animals. In part, this is due to their roles in guarding germ cell genomes against the activity of mobile genetic elements. piRNA populations direct Piwi proteins to silence transposon targets and, as such, form a molecular code that discriminates transposons from endogenous genes. Information ultimately carried by piRNAs is encoded within genomic loci, termed piRNA clusters. These give rise to long, single-stranded, primary transcripts that are processed into piRNAs. Despite the biological importance of this pathway, neither the characteristics that define a locus as a source of piRNAs nor the mechanisms that catalyze primary piRNA biogenesis are well understood. We searched an EMS-mutant collection annotated for fertility phenotypes for genes involved in the piRNA pathway. Twenty-seven homozygous sterile strains showed transposon-silencing defects. One of these, which strongly impacted primary piRNA biogenesis, harbored a causal mutation in CG5508, a member of the Drosophila glycerol-3-phosphate O-acetyltransferase (GPAT) family. These enzymes catalyze the first acylation step on the path to the production of phosphatidic acid (PA). Though this pointed strongly to a function for phospholipid signaling in the piRNA pathway, a mutant form of CG5508, which lacks the GPAT active site, still functions in piRNA biogenesis. We have named this new biogenesis factor Minotaur.


Assuntos
Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Glicerol-3-Fosfato O-Aciltransferase/metabolismo , RNA Interferente Pequeno/biossíntese , Sequência de Aminoácidos , Animais , Animais Geneticamente Modificados , Proteínas Argonautas/genética , Proteínas Argonautas/metabolismo , Domínio Catalítico , Elementos de DNA Transponíveis/genética , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Feminino , Genes de Insetos , Glicerol-3-Fosfato O-Aciltransferase/genética , Masculino , Dados de Sequência Molecular , Mutação , Fosfolipídeos/metabolismo , RNA Interferente Pequeno/genética , Transdução de Sinais
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