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1.
Int J Radiat Oncol Biol Phys ; 119(1): 90-99, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38163520

RESUMO

PURPOSE: High-dose-rate brachytherapy (HDR-BT) and external beam radiation therapy (EBRT) are effective treatments for prostate cancer but cause genitourinary (GU) and gastrointestinal (GI) toxicities. There is no consensus on the timing of HDR-BT in relation to EBRT and the effect of sequencing on patients. The primary objective was to assess differences, if any, in the incidence of grade (G) 3 or higher GU toxicities from treatment. We also aimed to explore the incidence of G1 to G4 GI toxicities, quality of life (QOL), and patient satisfaction. Suppression of prostate-specific antigen (PSA) and signals for survival differences were also analyzed. METHODS AND MATERIALS: This was a single-center randomized trial in patients with intermediate- and high-risk localized prostate cancer who received HDR-BT before (Arm A) or after (Arm B) EBRT. Toxicities were graded using Common Terminology Criteria for Adverse Events (CTCAE). The International Prostate Symptom Score (IPSS) was used to assess lower urinary tract symptoms. The International Index of Erectile Function scale (IIEF) and Functional Assessment of Cancer Therapy-Prostate (FACT-P) were used to assess erectile dysfunction and QOL at 0, 3, 9, and 12 months. RESULTS: Fifty patients were recruited to each arm, with 48 and 46 patients completing treatment and follow-up in each arm, 81.5% of whom had high-risk disease. There were no G3 or G4 GU or GI toxicities. G1 urinary frequency was the most common adverse event experienced in both arms, peaking in incidence 3 months after treatment commenced (45.7% and 42.2% in Arm A and B, respectively). Up to 11% of patients reported G1 urinary frequency at 12 months. Other G1 GU toxicities experienced by >10% of patients were urinary tract obstruction, tract pain, and urgency. These symptoms also peaked in incidence at 3 months. G2 GU toxicities were uncommon and experienced in a maximum of 2 patients within each arm at any time point. Over 30% of patients had G1 flatulence at baseline, and this remained the most frequently occurring G1 GI toxicity throughout the study, peaking at 12 months (21.4% and 25.6% in Arm A and B, respectively). Other GI toxicities experienced by more than 10% of patients were GI pain, proctitis, and rectal mucositis, most of which demonstrated a peak incidence at 3 or 9 months. G2 GI toxicities were uncommon except for G2 flatulence. No significant difference was found in CTCAE, IPSS, IIEF, FACT-P, and QOL scores between the arms. Median prostate-specific antigen (PSA) follow-up was 5 years. Seven patients had treatment failure in each arm. Disease Free Survival (DFS) was 93.3% and 90.7% at 5 years in Arm A and B, respectively, with median failure time of 60 and 48 months in Arm A and B, respectively. There were no statistically significant differences between arms. CONCLUSIONS: The sequencing of HDR-BT and EBRT did not affect the incidence of G3 or G4 toxicities, and no significant differences were seen in other patient-reported outcomes. Treatment was well tolerated with maintained QOL scores. Treatment failure was low in both arms in a high-risk cohort; however, a larger study with longer follow-up is underway to establish whether the difference in median time to failure between the 2 arms is a signal of superiority.


Assuntos
Braquiterapia , Neoplasias da Próstata , Masculino , Humanos , Braquiterapia/métodos , Antígeno Prostático Específico , Qualidade de Vida , Flatulência/etiologia , Dor/etiologia , Dosagem Radioterapêutica
2.
AORN J ; 118(5): 297-305, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37882597

RESUMO

After noting an elevated surgical site infection rate in 2019 associated with colorectal surgeries, leaders at two Central Virginia health system hospitals convened an interdisciplinary team to audit current practices and research infection prevention strategies. After identifying a lack of standardization in care processes for colorectal surgery patients and reviewing the literature on colorectal bundles, the team created a bundle focusing on the use of antibiotics, chlorhexidine gluconate wipes or baths, separate closing instrument trays, nasal decolonization, bowel preparation, and maintaining patient normothermia. After synthesis and stakeholder input, the team implemented the colorectal bundle along with a checklist for all users to complete to ensure compliance and standardization of practice and for auditing purposes. Implementation results were positive: the total number of colorectal infections decreased from nine in 2020 to three in 2021. Education was critical to securing staff member engagement for successful implementation of and compliance with the bundle.


Assuntos
Neoplasias Colorretais , Pacotes de Assistência ao Paciente , Humanos , Infecção da Ferida Cirúrgica/prevenção & controle , Melhoria de Qualidade , Lista de Checagem , Pacotes de Assistência ao Paciente/métodos
3.
Phlebology ; 36(7): 505-514, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33435839

RESUMO

INTRODUCTION: The mainstay of treatment for venous ulceration remains compression therapy. Velcro Wrap devices are being increasingly used in these patients despite limited evidence. This feasibility study aimed to compare standard bandaging to the JuxtaCures™ Velcro wrap device. METHODS: A single centre, unblinded RCT compared participants with venous ulceration randomised to either the JuxtaCures™ device or short stretch bandaging. Participants were followed up for 26 weeks. RESULTS: 160 participants were screened with 40 randomised. 3 participants in bandaging and 1 in JuxtaCures™ didn't complete the study. 60% in JuxtaCures™ healed v 55% in bandaging despite larger ulcers in the JuxtaCures™ arm (9.33 cm2 v 6.97 cm2). There was no significant difference in time to healing (12.17 v 13.64 weeks). JuxtaCures™ showed improved ulcer reduction for those that didn't heal (14.91-5.00 cm2 v 14.20-8.62 cm2; P = 0.06). JuxtaCures™ had more consistent sub-bandage pressure dropping from 39-36 mmHg versus 41-25 mmHg in bandaging between application and removal (P < 0.001). Quality of life (EQ5D) was improved in JuxtaCures at 3 months (mean difference 0.14, p = 0.04), but not at 1 and 6 months, or in disease specific quality of life. Cost was lower in JuxtaCures™ £842.47 v £1064.68. Duration of appointment was significantly shorter in JuxtaCures™ (41 minutes v 53 minutes; P = 0.003). CONCLUSION: This study has shown the feasibility and necessity of running a multicentre trial to evaluate the use of Velcro wrap devices for venous ulceration. It highlights the potential benefits of more consistent pressure, increased self-care, and potential with regards to ulcer healing, cost, nursing resource and quality of life.


Assuntos
Qualidade de Vida , Úlcera Varicosa , Bandagens Compressivas , Estudos de Viabilidade , Humanos , Úlcera Varicosa/terapia , Cicatrização
4.
Clin Nutr ; 40(5): 3643-3649, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33413912

RESUMO

OBJECTIVE: There is increasing evidence that red and processed meat consumption is associated with increased risk of cardiovascular (CV) disease. However, little literature reported the association among people with obesity versus those without obesity. We sought to investigate this using the UK Biobank data. METHODS: In this large prospective population-based cohort study, the red and processed meat consumption was assessed through the UK Biobank touch-screen questionnaire at baseline. The estimated hazards ratios (HRs) with 95% confidence intervals (CIs) were obtained from the Cox proportional hazard models to assess the association between red and processed meat consumption and the risk of CV death, cerebrovascular, and ischemic heart diseases in participants with and without obesity. RESULTS: Of 428,070 participants, 100,175 (23.4%) were obese with the mean age of 56 (SD: 7.9) years old and 54% were female. Participants without obesity, the mean age was 56 (SD: 5.2) years old and 55% were female. The overall median follow-up was 7.2 (IQR: 6.5-7.8) years. red and processed meat consumption had increased risk of CV death (HR (95%CI):1.04 (1.01-1.08) per week serve for participants with obesity and 1.04 (1.02-1.07) for those without obesity) after adjusted for age, sex, ethnicity, education, smoking and alcohol status and overall health. The moderate positive association between red and processed meat consumption and ischemic heart disease was only observed in participants without obesity (HR (95%CI): 1.15 (1.00-1.31) for the highest versus lowest terciles of red and processed meat consumption). No association was found with cerebrovascular disease in the participants regardless of obesity. CONCLUSIONS: Consumption frequency of red and processed meat is associated with higher risk of CV death regardless of obesity. The risk of ischemic heart disease associated with red and processed meat consumption may be higher in participants without obesity. Further studies are needed to understand the full extent of the mechanism of the association.


Assuntos
Doenças Cardiovasculares , Dieta , Obesidade , Carne Vermelha/estatística & dados numéricos , Doenças Cardiovasculares/complicações , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/mortalidade , Dieta/mortalidade , Dieta/estatística & dados numéricos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/complicações , Obesidade/epidemiologia , Obesidade/mortalidade , Estudos Prospectivos , Reino Unido
5.
Public Health Pract (Oxf) ; 2: 100065, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36101609

RESUMO

Objectives: Previous studies suggest that changes in body weight can lead to an increased risk of mortality in the general population, although the results are controversial. The current study sought to investigate this association further using data from the UK Biobank. Study design: This is a large prospective population-based cohort study. Data were derived from the UK Biobank, with the initial assessments commencing between 2006 and 2010. Methods: Proportional hazard models were used to assess the association between self-reported weight change and risk of all-cause, cancer and cardiovascular mortality. The effect of gender was also investigated. Results: Of 433,829 participants with data for self-reported weight change, the mean age was 56 (standard deviation [SD]: 8.1) years and 55% were female. In total, 55% of participants reported no weight change, 28% gained weight, 15% lost weight, 2% did not know and 0.1% preferred not to give an answer. The median follow-up was 7.1 (interquartile range [IQR]: 6.4-7.8) years. Compared with participants with no weight change, those with weight loss had an increased risk of all-cause mortality (adjusted hazard ratio [HR] 1.25, 95% confident interval [CI] 1.18-1.32), cancer death (HR 1.17, 95% CI 1.08-1.27) and cardiovascular death (HR 1.26, 95% CI 1.12-1.43). Similarly, participants reporting weight gain also had an increased risk of all-cause mortality (HR 1.08, 95% CI 1.02-1.13), cancer death (HR 1.14, 95% CI 1.07-1.22) and cardiovascular death (HR 1.27, 95% CI 1.14-1.42). Participants who had a response 'do not know' or 'prefer not to answer' showed an increased risk of all-cause and cardiovascular mortality, particularly in men. Conclusions: The results of this study highlight the importance of maintaining a stable weight in middle-aged adults. Further studies are needed to understand the pathophysiology of weight change and its effects on mortality.

7.
BMJ Open ; 8(10): e026770, 2018 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-30385451

RESUMO

INTRODUCTION: Patients with severe dry eye disease (DED) often have limited treatment options with standard non-surgical management focused on the use of artificial tears for lubrication and anti-inflammatory drugs. However, artificial tears do not address the extraordinary complexity of human tears. Crudely, human tears with its vast constituents is essentially filtered blood. Blood and several blood-derived products including autologous serum, have been studied as tear substitutes. This study proposes to test the use of whole, fresh, autologous blood obtained from a finger prick for treatment of severe DED. METHODS AND ANALYSIS: The research team at the two participating sites will approach patients with severe DED for this study. Recruitment will take place over 12 months and we expect to recruit 60 patients in total. The primary outcome of this feasibility study is to estimate the proportion of eligible patients approached who consent to and comply with study procedures including treatment regimen and completion of required questionnaires. The secondary outcome measures, although not powered for in this feasibility, include corneal inflammation (assessed by the Oxford corneal staining guide), patient pain and symptoms scores (assessed by the Ocular Surface Disease Index Score), and objective signs of DED as indicated by visual acuity (assessed by Schirmer's test, tear break-up time, lower and/or upper tear meniscus height measurement). Other secondary outcomes include patients' quality of life (assessed using the validated EQ-5D-5L Questionnaire), cost to the National Health Service (NHS) and patient (assessed via use of NHS services and privately purchased over-the-counter treatment related to DED) and safety measure of pressure within the eye (assessed by the Intraocular Pressure (IOP) Score). ETHICS AND DISSEMINATION: This protocol and any subsequent amendments, along with any accompanying material provided to the participant in addition to any advertising material used in this trial have been approved by the East of England - Cambridgeshire and Hertfordshire Research Ethics Committee (REC reference: 17/EE/0508). Written approval from the committee was obtained and subsequently submitted to the respective Trust's Research and Development (R&D) office with final NHS R&D approval obtained. Data obtained from this study will be published in a suitable peer-review journal and will also presented at international ophthalmic conferences including the American Academy of Ophthalmology, the Royal College of Ophthalmology Annual Congress, the Association for Research and Vision and Ophthalmology, and the European Society of Cataract and Refractive Surgery. Information will be provided to patient groups and charities such as the Sjogren's Society and the Royal National Institute of Blind People. This will also be shared with the study participants as well as with relevant patient groups and charities. TRIAL REGISTRATION NUMBER: NCT03395431; Pre-results.


Assuntos
Síndromes do Olho Seco/terapia , Lubrificantes Oftálmicos/uso terapêutico , Soro , Inglaterra , Estudos de Viabilidade , Humanos , Estudos Multicêntricos como Assunto , Soluções Oftálmicas/uso terapêutico , Modelos de Riscos Proporcionais , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , Índice de Gravidade de Doença , Método Simples-Cego , Cloreto de Sódio/uso terapêutico , Acuidade Visual
8.
BMC Complement Altern Med ; 17(1): 439, 2017 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-28865459

RESUMO

BACKGROUND: Indigo naturalis is a Traditional Chinese Medicine (TCM) ingredient long-recognized as a therapy for several inflammatory conditions, including psoriasis. However, its mechanism is unknown due to lack of knowledge about the responsible chemical entity. We took a different approach to this challenge by investigating the molecular profile of Indigo naturalis treatment and impacted pathways. METHODS: A randomized, double-blind, placebo-controlled clinical study was conducted using Indigo naturalis as topical monotherapy to treat moderate plaque psoriasis in a Chinese cohort (n = 24). Patients were treated with Indigo naturalis ointment (n = 16) or matched placebo (n = 8) twice daily for 8 weeks, with 1 week of follow-up. RESULTS: At week 8, significant improvements in Psoriasis Area and Severity Index (PASI) scores from baseline were observed in Indigo naturalis-treated patients (56.3% had 75% improvement [PASI 75] response) compared with placebo (0.0%). A gene expression signature of moderate psoriasis was established from baseline skin biopsies, which included the up-regulation of the interleukin (IL)-17 pathway as a key component; Indigo naturalis treatment resulted in most of these signature genes returning toward normal, including down-regulation of the IL-17 pathway. Using an in vitro keratinocyte assay, an IL-17-inhibitory effect was observed for tryptanthrin, a component of Indigo naturalis. CONCLUSIONS: This study demonstrated the clinical efficacy of Indigo naturalis in moderate psoriasis, and exemplified a novel experimental medicine approach to understand TCM targeting mechanisms. TRIAL REGISTRATION: NCT01901705 .


Assuntos
Indigofera/química , Interleucina-17/imunologia , Extratos Vegetais/administração & dosagem , Psoríase/tratamento farmacológico , Adulto , Idoso , Feminino , Humanos , Interleucina-17/genética , Masculino , Pessoa de Meia-Idade , Psoríase/genética , Psoríase/imunologia , Resultado do Tratamento , Adulto Jovem
9.
JMIR Res Protoc ; 4(2): e49, 2015 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-25926023

RESUMO

BACKGROUND: Prostate cancer is the most common cancer in males in the UK and affects around 105 men for every 100,000. The role of radiotherapy in the management of prostate cancer significantly changed over the last few decades with developments in brachytherapy, external beam radiotherapy (EBRT), intensity-modulated radiotherapy (IMRT), and image-guided radiotherapy (IGRT). One of the challenging factors of radiotherapy treatment of localized prostate cancer is the development of acute and late genitourinary and gastrointestinal toxicities. The recent European guidelines suggest that there is no consensus regarding the timing of high-dose rate (HDR) brachytherapy and EBRT. The schedules vary in different institutions where an HDR boost can be given either before or after EBRT. Few centers deliver HDR in between the fractions of EBRT. OBJECTIVE: Assessment of acute genitourinary and gastrointestinal toxicities at various time points to better understand if the order in which treatment modality is delivered (ie, HDR brachytherapy or EBRT first) has an effect on the toxicity profile. METHODS: Timing of HDR brachytherapy with EBRT in Prostate CAncer (THEPCA) is a single-center, open, randomized controlled feasibility trial in patients with intermediate and high-risk localized prostate cancer. A group of 50 patients aged 18 years old and over with histological diagnosis of prostate cancer (stages T1b-T3BNOMO), will be randomized to one of two treatment arms (ratio 1:1), following explanation of the study and informed consent. Patients in both arms of the study will be treated with HDR brachytherapy and EBRT, however, the order in which they receive the treatments will vary. In Arm A, patients will receive HDR brachytherapy before EBRT. In Arm B (control arm), patients will receive EBRT before HDR brachytherapy. Study outcomes will look at prospective assessment of genitourinary and gastrointestinal toxicities. The primary endpoint will be grade 3 genitourinary toxicity and the secondary endpoints will be all other grades of genitourinary toxicities (grades 1 and 2), gastrointestinal toxicities (grades 1 to 4), prostate-specific antigen (PSA) recurrence-free survival, overall survival, and quality of life. RESULTS: Results from this feasibility trial will be available in mid-2016. CONCLUSIONS: If the results from this feasibility trial show evidence that the sequence of treatment modality does affect the patients' toxicity profiles, then funding would be sought to conduct a large, multicenter, randomized controlled trial. TRIAL REGISTRATION: International Standard Randomized Controlled Trial Number (ISRCTN): 15835424; http://www.isrctn.com/ISRCTN15835424 (Archived by WebCite at http://www.webcitation.org/6Xz7jfg1u).

10.
Mol Cell Biol ; 33(4): 763-72, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23230266

RESUMO

Centromeres, the sites of spindle attachment during mitosis and meiosis, are located in specific positions in the human genome, normally coincident with diverse subsets of alpha satellite DNA. While there is strong evidence supporting the association of some subfamilies of alpha satellite with centromere function, the basis for establishing whether a given alpha satellite sequence is or is not designated a functional centromere is unknown, and attempts to understand the role of particular sequence features in establishing centromere identity have been limited by the near identity and repetitive nature of satellite sequences. Utilizing a broadly applicable experimental approach to test sequence competency for centromere specification, we have carried out a genomic and epigenetic functional analysis of endogenous human centromere sequences available in the current human genome assembly. The data support a model in which functionally competent sequences confer an opportunity for centromere specification, integrating genomic and epigenetic signals and promoting the concept of context-dependent centromere inheritance.


Assuntos
Centrômero/genética , DNA Satélite/genética , Genoma Humano , Autoantígenos/genética , Sequência de Bases , Proteína Centromérica A , Proteínas Cromossômicas não Histona/genética , Cromossomos Artificiais/genética , Bases de Dados Genéticas , Humanos , Dados de Sequência Molecular
11.
BMC Genomics ; 13: 324, 2012 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-22817545

RESUMO

BACKGROUND: Centromeres are sites of chromosomal spindle attachment during mitosis and meiosis. While the sequence basis for centromere identity remains a subject of considerable debate, one approach is to examine the genomic organization at these active sites that are correlated with epigenetic marks of centromere function. RESULTS: We have developed an approach to characterize both satellite and non-satellite centromeric sequences that are missing from current assemblies in complex genomes, using the dog genome as an example. Combining this genomic reference with an epigenetic dataset corresponding to sequences associated with the histone H3 variant centromere protein A (CENP-A), we identify active satellite sequence domains that appear to be both functionally and spatially distinct within the overall definition of satellite families. CONCLUSIONS: These findings establish a genomic and epigenetic foundation for exploring the functional role of centromeric sequences in the previously sequenced dog genome and provide a model for similar studies within the context of less-characterized genomes.


Assuntos
Centrômero/genética , Genoma/genética , Animais , Sequência de Bases , Imunoprecipitação da Cromatina , Elementos de DNA Transponíveis/genética , DNA Satélite/genética , Bases de Dados Genéticas , Cães , Biblioteca Gênica , Células Madin Darby de Rim Canino , Anotação de Sequência Molecular
12.
J Invest Dermatol ; 132(11): 2552-64, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22763790

RESUMO

Psoriasis is a complex disease with an expanding definition of its pathological features. We sought to expand/refine the psoriasis transcriptome using 85 paired lesional and non-lesional samples from a cohort of patients with moderate-to-severe psoriasis vulgaris who were not receiving active psoriasis therapy. This new analysis identified 4,175 probe sets (representing 2,725 unique known genes) as being differentially expressed in psoriasis lesions compared with matched biopsies of non-lesional skin when the following criteria were applied: >2-fold change and false discovery rate <0.05. These probe sets represent the largest and most comprehensive set of genes defining psoriasis at the molecular level and within the previously unidentified genes, a link to functional pathways associated with metabolic diseases/diabetes and to cardiovascular risk pathways is identified. In addition, we profiled the serum of moderate-to-severe psoriatics compared with healthy controls to assess the overlap of overexpressed lesional genes with overexpressed systemic proteins. We identified linkage of functional pathways in lesional skin associated with metabolic diseases/diabetes and cardiovascular risk with those pathways overexpressed in the serum, suggesting a potential linkage between altered gene transcription in the skin and comorbidities commonly seen in patients with moderate-to-severe psoriasis.


Assuntos
Psoríase/epidemiologia , Psoríase/genética , Índice de Gravidade de Doença , Transcriptoma , Adulto , Biomarcadores/sangue , Biópsia , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/genética , Estudos de Coortes , Comorbidade , Dermatite/sangue , Dermatite/epidemiologia , Dermatite/genética , Diabetes Mellitus/sangue , Diabetes Mellitus/epidemiologia , Diabetes Mellitus/genética , Feminino , Humanos , Masculino , Doenças Metabólicas/sangue , Doenças Metabólicas/epidemiologia , Doenças Metabólicas/genética , Pessoa de Meia-Idade , Psoríase/sangue , Pele/patologia
13.
Chromosome Res ; 20(5): 621-33, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22801774

RESUMO

Advances in human genomics have accelerated studies in evolution, disease, and cellular regulation. However, centromere sequences, defining the chromosomal interface with spindle microtubules, remain largely absent from ongoing genomic studies and disconnected from functional, genome-wide analyses. This disparity results from the challenge of predicting the linear order of multi-megabase-sized regions that are composed almost entirely of near-identical satellite DNA. Acknowledging these challenges, the field of human centromere genomics possesses the potential to rapidly advance given the availability of individual, or personalized, genome projects matched with the promise of long-read sequencing technologies. Here I review the current genomic model of human centromeres in consideration of those studies involving functional datasets that examine the role of sequence in centromere identity.


Assuntos
Centrômero/metabolismo , Cromossomos Humanos/metabolismo , Genoma Humano , Centrômero/genética , Montagem e Desmontagem da Cromatina , Duplicação Cromossômica , Mapeamento Cromossômico , Cromossomos Humanos/genética , DNA Satélite/genética , DNA Satélite/metabolismo , Evolução Molecular , Genética Populacional/métodos , Humanos , Modelos Genéticos , Mapeamento de Interação de Proteínas
14.
Genome Biol Evol ; 3: 1136-49, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21828373

RESUMO

Centromeric regions in many complex eukaryotic species contain highly repetitive satellite DNAs. Despite the diversity of centromeric DNA sequences among species, the functional centromeres in all species studied to date are marked by CENP-A, a centromere-specific histone H3 variant. Although it is well established that families of multimeric higher-order alpha satellite are conserved at the centromeres of human and great ape chromosomes and that diverged monomeric alpha satellite is found in old and new world monkey genomes, little is known about the organization, function, and evolution of centromeric sequences in more distant primates, including lemurs. Aye-Aye (Daubentonia madagascariensis) is a basal primate and is located at a key position in the evolutionary tree to study centromeric satellite transitions in primate genomes. Using the approach of chromatin immunoprecipitation with antibodies directed to CENP-A, we have identified two satellite families, Daubentonia madagascariensis Aye-Aye 1 (DMA1) and Daubentonia madagascariensis Aye-Aye 2 (DMA2), related to each other but unrelated in sequence to alpha satellite or any other previously described primate or mammalian satellite DNA families. Here, we describe the initial genomic and phylogenetic organization of DMA1 and DMA2 and present evidence of higher-order repeats in Aye-Aye centromeric domains, providing an opportunity to study the emergence of chromosome-specific modes of satellite DNA evolution in primate genomes.


Assuntos
Autoantígenos/genética , Proteínas Cromossômicas não Histona/genética , DNA Satélite/genética , Evolução Molecular , Genoma , Família Multigênica , Primatas/genética , Animais , Sequência de Bases , Linhagem Celular , Centrômero/genética , Proteína Centromérica A , Feminino , Humanos , Masculino , Dados de Sequência Molecular , Filogenia , Primatas/classificação
15.
PLoS Genet ; 6(8)2010 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-20711355

RESUMO

Genome rearrangement often produces chromosomes with two centromeres (dicentrics) that are inherently unstable because of bridge formation and breakage during cell division. However, mammalian dicentrics, and particularly those in humans, can be quite stable, usually because one centromere is functionally silenced. Molecular mechanisms of centromere inactivation are poorly understood since there are few systems to experimentally create dicentric human chromosomes. Here, we describe a human cell culture model that enriches for de novo dicentrics. We demonstrate that transient disruption of human telomere structure non-randomly produces dicentric fusions involving acrocentric chromosomes. The induced dicentrics vary in structure near fusion breakpoints and like naturally-occurring dicentrics, exhibit various inter-centromeric distances. Many functional dicentrics persist for months after formation. Even those with distantly spaced centromeres remain functionally dicentric for 20 cell generations. Other dicentrics within the population reflect centromere inactivation. In some cases, centromere inactivation occurs by an apparently epigenetic mechanism. In other dicentrics, the size of the alpha-satellite DNA array associated with CENP-A is reduced compared to the same array before dicentric formation. Extra-chromosomal fragments that contained CENP-A often appear in the same cells as dicentrics. Some of these fragments are derived from the same alpha-satellite DNA array as inactivated centromeres. Our results indicate that dicentric human chromosomes undergo alternative fates after formation. Many retain two active centromeres and are stable through multiple cell divisions. Others undergo centromere inactivation. This event occurs within a broad temporal window and can involve deletion of chromatin that marks the locus as a site for CENP-A maintenance/replenishment.


Assuntos
Centrômero/metabolismo , Cromossomos Humanos/genética , Telômero/genética , Telômero/metabolismo , Linhagem Celular , Centrômero/genética , Cromossomos Humanos/metabolismo , DNA Satélite/genética , DNA Satélite/metabolismo , Humanos
16.
Clin Vaccine Immunol ; 15(1): 42-8, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18003817

RESUMO

The accurate detection and quantitation of cytokines in serum are important in the study of disease mechanisms, pathogenesis, and treatment. Serum cytokines can reflect processes that are occurring at the cellular or tissue level and thus provide a means of indirectly monitoring these processes. Multiplex detection of cytokines allows the simultaneous measurement of multiple cytokines in a sample, increasing the efficiency of measuring the cytokines while reducing the serum sample volumes required for the testing. Two commercially available multiplex platforms were evaluated (Pierce SearchLight and Meso Scale Discovery), using multiplexes capable of simultaneously detecting eight cytokines. The cytokines analyzed in this study were gamma interferon, vascular endothelial growth factor, tumor necrosis factor alpha, interleukin-6 (IL-6), macrophage inflammatory protein 1beta, monocyte chemoattractant protein 1, IL-12p40, and IL-4. The range of quantitation of the platforms, the recovery of spiked cytokines, and the detection of the cytokines in serum samples from subjects with ulcerative colitis, Crohn's disease, rheumatoid arthritis, and psoriasis were examined. The findings showed that the detection of the cytokines was highly dependent upon the platform, with the consistency of the detection of cytokines across platforms being dependent upon the cytokine being analyzed. A careful examination of platform assay performance must be made prior to utilizing multiplex platforms in a study. While some cytokines will give similar patterns of results across platforms, others will be highly variable. The use of the same platform within a study or across studies where data will be compared is advised.


Assuntos
Citocinas/sangue , Imunoensaio/métodos , Adulto , Idoso , Artrite Reumatoide/imunologia , Colite Ulcerativa/sangue , Colite Ulcerativa/imunologia , Doença de Crohn/sangue , Doença de Crohn/imunologia , Citocinas/biossíntese , Citocinas/imunologia , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Psoríase/imunologia , Kit de Reagentes para Diagnóstico
17.
Genome Res ; 15(10): 1344-56, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16169929

RESUMO

Structural changes (deletions, insertions, and inversions) between human and chimpanzee genomes have likely had a significant impact on lineage-specific evolution because of their potential for dramatic and irreversible mutation. The low-quality nature of the current chimpanzee genome assembly precludes the reliable identification of many of these differences. To circumvent this, we applied a method to optimally map chimpanzee fosmid paired-end sequences against the human genome to systematically identify sites of structural variation > or = 12 kb between the two species. Our analysis yielded a total of 651 putative sites of chimpanzee deletion (n = 293), insertions (n = 184), and rearrangements consistent with local inversions between the two genomes (n = 174). We validated a subset (19/23) of insertion and deletions using PCR and Southern blot assays, confirming the accuracy of our method. The events are distributed throughout the genome on all chromosomes but are highly correlated with sites of segmental duplication in human and chimpanzee. These structural variants encompass at least 24 Mb of DNA and overlap with > 245 genes. Seventeen of these genes contain exons missing in the chimpanzee genomic sequence and also show a significant reduction in gene expression in chimpanzee. Compared with the pioneering work of Yunis, Prakash, Dutrillaux, and Lejeune, this analysis expands the number of potential rearrangements between chimpanzees and humans 50-fold. Furthermore, this work prioritizes regions for further finishing in the chimpanzee genome and provides a resource for interrogating functional differences between humans and chimpanzees.


Assuntos
Genoma , Pan troglodytes/genética , Animais , Coleta de Dados , Humanos , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Deleção de Sequência
18.
PLoS Biol ; 3(4): e110, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15737067

RESUMO

Retroviral infections of the germline have the potential to episodically alter gene function and genome structure during the course of evolution. Horizontal transmissions between species have been proposed, but little evidence exists for such events in the human/great ape lineage of evolution. Based on analysis of finished BAC chimpanzee genome sequence, we characterize a retroviral element (Pan troglodytes endogenous retrovirus 1 [PTERV1]) that has become integrated in the germline of African great ape and Old World monkey species but is absent from humans and Asian ape genomes. We unambiguously map 287 retroviral integration sites and determine that approximately 95.8% of the insertions occur at non-orthologous regions between closely related species. Phylogenetic analysis of the endogenous retrovirus reveals that the gorilla and chimpanzee elements share a monophyletic origin with a subset of the Old World monkey retroviral elements, but that the average sequence divergence exceeds neutral expectation for a strictly nuclear inherited DNA molecule. Within the chimpanzee, there is a significant integration bias against genes, with only 14 of these insertions mapping within intronic regions. Six out of ten of these genes, for which there are expression data, show significant differences in transcript expression between human and chimpanzee. Our data are consistent with a retroviral infection that bombarded the genomes of chimpanzees and gorillas independently and concurrently, 3-4 million years ago. We speculate on the potential impact of such recent events on the evolution of humans and great apes.


Assuntos
Retrovirus Endógenos/genética , Hominidae/genética , Pan troglodytes/genética , Pongo pygmaeus/genética , Animais , Mapeamento Cromossômico , Gorilla gorilla/genética , Gorilla gorilla/virologia , Hominidae/virologia , Humanos , Íntrons/genética , Dados de Sequência Molecular , Pan troglodytes/virologia , Pongo pygmaeus/virologia , Biossíntese de Proteínas , Retroelementos/genética , Especificidade da Espécie , Transcrição Gênica
19.
J Vasc Nurs ; 21(1): 17-21; quiz 22-3, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12629493

RESUMO

This study examined perceived and objective health risks, health promotive behavior, risk perception, and knowledge of risk factors for peripheral arterial disease (PAD) in children of patients with PAD. Children of patients who had lower extremity distal arterial reconstructive surgery or amputation for complications of PAD completed an investigator-developed questionnaire. Risk factor and behavioral measures were self-reported. Data were collected by telephone interview. The sample consisted of 15 children of 6 patients. Subjects displayed optimistic bias regarding their risk for developing PAD, with 67% reporting their parent's illness had no impact on their health behaviors. Fifty-three percent felt their comparative risk was "about the same" as same-age, same-sex peers. Risk factor knowledge varied and none mentioned hypertension, age, obesity, or gender; the most commonly cited risk factor was diabetes mellitus. Forty-seven percent of the offspring never smoked, less than half exercised regularly, most were overweight or had class I or class II obesity, and most were unaware of their blood pressure or cholesterol levels. Despite frequent interactions with their affected parent, these children exhibited poor understanding of risk factors and personal risk of developing PAD and most did not participate in health promotive behaviors. Educational efforts by national societies promoting an understanding of modifiable risk factors must be improved. Future studies need to explore interventions designed to improve risk perception and health promotive behaviors.


Assuntos
Filhos Adultos , Arteriosclerose , Conhecimentos, Atitudes e Prática em Saúde , Doenças Vasculares Periféricas , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Fatores de Risco , Estados Unidos
20.
New Phytol ; 152(3): 419-430, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33862986

RESUMO

• The way in which novel genetic variation affects the patterns of phenotypic integration in natural populations is addressed here. • An experimental study is presented of the variability in integration caused by interpopulation hybridization and consequent genetic reshuffling, as well as by changes in the physical environment in the model system Arabidopsis thaliana (Brassicaceae). • Our results show a basic invariance of sets of covarying traits in A. thaliana, with changes in nutrient availability as the principal factor accounting for major departures from the general pattern and where differences in the genetic background of the recombinant lines are less important. In A. thaliana, the relationships among vegetative and reproductive traits form distinct clusters in multivariate space. A high degree of congruence was found between differences in the multivariate mean phenotype and the pattern of phenotypic integration, as expected on the basis of recent theoretical models. • This relationship might indicate strong selective constraints acting on the specialized life history of these populations, which are spring ephemerals inhabiting ruderal habitats and prone to competition avoidance.

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