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1.
Cell ; 157(4): 785-94, 2014 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-24813606

RESUMO

Polar bears are uniquely adapted to life in the High Arctic and have undergone drastic physiological changes in response to Arctic climates and a hyper-lipid diet of primarily marine mammal prey. We analyzed 89 complete genomes of polar bear and brown bear using population genomic modeling and show that the species diverged only 479-343 thousand years BP. We find that genes on the polar bear lineage have been under stronger positive selection than in brown bears; nine of the top 16 genes under strong positive selection are associated with cardiomyopathy and vascular disease, implying important reorganization of the cardiovascular system. One of the genes showing the strongest evidence of selection, APOB, encodes the primary lipoprotein component of low-density lipoprotein (LDL); functional mutations in APOB may explain how polar bears are able to cope with life-long elevated LDL levels that are associated with high risk of heart disease in humans.


Assuntos
Evolução Biológica , Ursidae/classificação , Ursidae/genética , Adaptação Fisiológica , Tecido Adiposo/metabolismo , Animais , Apolipoproteínas B/química , Apolipoproteínas B/metabolismo , Regiões Árticas , Ácidos Graxos/metabolismo , Fluxo Gênico , Genética Populacional , Genoma , Ursidae/fisiologia
2.
Surgeon ; 19(5): e281-e288, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33558141

RESUMO

During the pandemic healthcare faced great pressure on the availability of protective equipment. This paper describes the entire novel innovative process of design optimisation, production and deployment of face-visors to NHS frontline workers during SARS-CoV-2 pandemic. The described innovative journey spans collaboration between clinicians and academic colleagues for design to the implementation with industry partners of a face-visor for use in a healthcare setting. It identifies the enablers and barriers to development along with the strategies employed to produce a certified reusable, adjustable, high volume and locally produced face-visor. The article also explores aspects of value, scalability, spread and sustainability all of which are essential features of innovation.


Assuntos
COVID-19/prevenção & controle , Difusão de Inovações , Colaboração Intersetorial , Invenções , Equipamento de Proteção Individual , Medicina Estatal , COVID-19/epidemiologia , COVID-19/transmissão , Desenho de Equipamento , Humanos , Reino Unido
3.
Mol Biol Evol ; 36(6): 1239-1253, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-30913563

RESUMO

Genomic imprinting is an epigenetic phenomenon where autosomal genes display uniparental expression depending on whether they are maternally or paternally inherited. Genomic imprinting can arise from parental conflicts over resource allocation to the offspring, which could drive imprinted loci to evolve by positive selection. We investigate whether positive selection is associated with genomic imprinting in the inbreeding species Arabidopsis thaliana. Our analysis of 140 genes regulated by genomic imprinting in the A. thaliana seed endosperm demonstrates they are evolving more rapidly than expected. To investigate whether positive selection drives this evolutionary acceleration, we identified orthologs of each imprinted gene across 34 plant species and elucidated their evolutionary trajectories. Increased positive selection was sought by comparing its incidence among imprinted genes with nonimprinted controls. Strikingly, we find a statistically significant enrichment of imprinted paternally expressed genes (iPEGs) evolving under positive selection, 50.6% of the total, but no such enrichment for positive selection among imprinted maternally expressed genes (iMEGs). This suggests that maternally- and paternally expressed imprinted genes are subject to different selective pressures. Almost all positively selected amino acids were fixed across 80 sequenced A. thaliana accessions, suggestive of selective sweeps in the A. thaliana lineage. The imprinted genes under positive selection are involved in processes important for seed development including auxin biosynthesis and epigenetic regulation. Our findings support a genomic imprinting model for plants where positive selection can affect paternally expressed genes due to continued conflict with maternal sporophyte tissues, even when parental conflict is reduced in predominantly inbreeding species.


Assuntos
Arabidopsis/genética , Evolução Molecular , Impressão Genômica , Seleção Genética , Proteínas de Arabidopsis/genética , RNA Polimerases Dirigidas por DNA/genética
4.
BMC Evol Biol ; 19(1): 154, 2019 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-31345177

RESUMO

BACKGROUND: Genes that encode proteins associated with sperm competition, fertilization, and sexual conflicts of interest are often among the most rapidly evolving parts of animal genomes. One family of sperm-expressed genes (Zp3r, C4bpa) in the mammalian gene cluster called the regulator of complement activation (RCA) encodes proteins that bind eggs and mediate reproductive success, and are therefore expected to show high relative rates of nonsynonymous nucleotide substitution in response to sexual selection in comparison to other genes not involved in gamete binding at fertilization. We tested that working hypothesis by using phylogenetic models of codon evolution to identify episodes of diversifying positive selection. We used a comparative approach to quantify the evidence for episodic diversifying selection acting on RCA genes with known functions in fertilization (and sensitivity to sexual selection), and contrast them with other RCA genes in the same gene family that function in innate immunity (and are not sensitive to sexual selection). RESULTS: We expected but did not find evidence for more episodes of positive selection on Zp3r in Glires (the rodents and lagomorphs) or on C4BPA in Primates, in comparison to other paralogous RCA genes in the same taxon, or in comparison to the same orthologous RCA gene in the other taxon. That result was not unique to RCA genes: we also found little evidence for more episodes of diversifying selection on genes that encode selective sperm-binding molecules in the egg coat or zona pellucida (Zp2, Zp3) in comparison to members of the same gene family that encode structural elements of the egg coat (Zp1, Zp4). Similarly, we found little evidence for episodic diversifying selection acting on two other recently discovered genes (Juno, Izumo1) that encode essential molecules for sperm-egg fusion. CONCLUSIONS: These negative results help to illustrate the importance of a comparative context for this type of codon model analysis. The results may also point to other phylogenetic contexts in which the effects of selection acting on these fertilization proteins might be more readily discovered and documented in mammals and other taxa.


Assuntos
Epistasia Genética , Evolução Molecular , Fertilização/genética , Mamíferos/genética , Animais , Códon/genética , Feminino , Variação Genética , Masculino , Camundongos , Fenótipo , Filogenia , Seleção Genética
5.
Transpl Int ; 30(6): 566-578, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28211192

RESUMO

Controversy exists as to whether African American (AA) transplant recipients are at risk for developing de novo donor-specific anti-human leucocyte antigen (HLA) antibody (dnDSA). We studied 341 HLA-mismatched, primary renal allograft recipients who were consecutively transplanted between 3/1999 and 12/2010. Sera were collected sequentially pre- and post-transplant and tested for anti-HLA immunoglobulin G (IgG) via single antigen bead assay. Of the 341 transplant patients (225 AA and 116 non-AA), 107 developed dnDSA at a median of 9.2 months post-transplant. AA patients had a 5-year dnDSA incidence of 35%. This was significantly higher than the 5-year dnDSA incidence for non-AA patients (21%). DQ mismatch (risk) and receiving a living-related donor (LRD) transplant (protective) were transplant factors associated with dnDSA. Within the AA patient cohort, HLA-DQ mismatch, not-receiving a LRD transplant, nonadherence and BK viraemia were the most common factors associated with early dnDSA (occurring <24 months post-transplant). Nonadherence and pretransplant diabetes history were the strong precursors to late dnDSA. Despite the higher rates of dnDSA in the AA cohort, post-dnDSA survival was the same in AA and non-AA patients. This study suggests that DQ matching, increasing LRD transplantation in AA patients and minimizing under-immunosuppression will be key to preventing dnDSA.


Assuntos
Isoanticorpos/sangue , Transplante de Rim , Grupos Raciais , Doadores de Tecidos , Adulto , Negro ou Afro-Americano , Especificidade de Anticorpos , Vírus BK , Estudos de Coortes , Feminino , Rejeição de Enxerto/etiologia , Rejeição de Enxerto/imunologia , Antígenos HLA/imunologia , Antígenos HLA-DQ/imunologia , Teste de Histocompatibilidade , Humanos , Imunoglobulina G/sangue , Transplante de Rim/efeitos adversos , Doadores Vivos , Masculino , Pessoa de Meia-Idade , Infecções por Polyomavirus/etiologia , Fatores de Risco , Fatores de Tempo , Infecções Tumorais por Vírus/etiologia , Viremia/etiologia , População Branca
6.
J Cell Biochem ; 117(10): 2340-5, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-26945839

RESUMO

Constitutive activation of mutant K ras (Kirsten rat sarcoma viral oncogene homologue) and disassembly of E-cadherin-catenin complex (E-cadherin, α-catenin, ß-catenin, and γ-catenin) play an important role in apoptosis, differentiation, and cell proliferation. In this study, the expression pattern of K ras and E-cadherin-catenin complex has been evaluated in normal and mutant colorectal cancer cell lines with an object to determine its impact on disassociation of cells from one another. We addressed the expression analysis of K ras with reference to its association with adherence molecules in two colorectal cancer cell lines, that is, Caco-2 (wild type K ras served as a control) and DLD1 (heterozygous mutation at codon 13) at message level by qRT-PCR and translational level by western blotting. Compared to the control Caco-2 cell lines, the K ras in DLD1 cell lines showed slightly higher values while α-catenin showed a slight lower (1.3-folds), ß-catenin and E-cadherin showed significantly lower expression (4.2-fold decrease). It can be inferred that a possible cross talk exists between K ras and adherent junction mediated signalling. Mutation at codon 13 (G to D) leads to the overexpression of K ras and reduced expression of adherent junction complex resulting in metastasis. J. Cell. Biochem. 117: 2340-2345, 2016. © 2016 Wiley Periodicals, Inc.


Assuntos
Caderinas/metabolismo , Cateninas/metabolismo , Neoplasias Colorretais/secundário , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Animais , Western Blotting , Neoplasias Colorretais/metabolismo , Humanos , Técnicas Imunoenzimáticas , Metástase Neoplásica , Ratos , Células Tumorais Cultivadas
7.
Mol Biol Evol ; 32(7): 1717-29, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25758009

RESUMO

It has been proposed that positive selection may be associated with protein functional change. For example, human and macaque have different outcomes to HIV infection and it has been shown that residues under positive selection in the macaque TRIM5α receptor locate to the region known to influence species-specific response to HIV. In general, however, the relationship between sequence and function has proven difficult to fully elucidate, and it is the role of large-scale studies to help bridge this gap in our understanding by revealing major patterns in the data that correlate genotype with function or phenotype. In this study, we investigate the level of species-specific positive selection in innate immune genes from human and mouse. In total, we analyzed 456 innate immune genes using codon-based models of evolution, comparing human, mouse, and 19 other vertebrate species to identify putative species-specific positive selection. Then we used population genomic data from the recently completed Neanderthal genome project, the 1000 human genomes project, and the 17 laboratory mouse genomes project to determine whether the residues that were putatively positively selected are fixed or variable in these populations. We find evidence of species-specific positive selection on both the human and the mouse branches and we show that the classes of genes under positive selection cluster by function and by interaction. Data from this study provide us with targets to test the relationship between positive selection and protein function and ultimately to test the relationship between positive selection and discordant phenotypes.


Assuntos
Adaptação Fisiológica/genética , Evolução Biológica , Imunidade Inata/genética , Aminoácidos/metabolismo , Animais , Genética Populacional , Humanos , Camundongos , Filogenia , Estrutura Terciária de Proteína , Seleção Genética , Especificidade da Espécie , Receptor 3 Toll-Like/química
8.
Mutagenesis ; 31(3): 323-8, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26208916

RESUMO

Assessment of genetic toxicity and/or carcinogenic activity is an essential element of chemical screening programs employed to protect human health. Dose-response and gene mutation data are frequently analysed by industry, academia and governmental agencies for regulatory evaluations and decision making. Over the years, a number of efforts at different institutions have led to the creation and curation of databases to house genetic toxicology data, largely, with the aim of providing public access to facilitate research and regulatory assessments. This article provides a brief introduction to a new genetic toxicology portal called Mutation Analysis Informatics Tools (MutAIT) (www.mutait.org) that provides easy access to two of the largest genetic toxicology databases, the Mammalian Gene Mutation Database (MGMD) and TransgenicDB. TransgenicDB is a comprehensive collection of transgenic rodent mutation data initially compiled and collated by Health Canada. The updated MGMD contains approximately 50 000 individual mutation spectral records from the published literature. The portal not only gives access to an enormous quantity of genetic toxicology data, but also provides statistical tools for dose-response analysis and calculation of benchmark dose. Two important R packages for dose-response analysis are provided as web-distributed applications with user-friendly graphical interfaces. The 'drsmooth' package performs dose-response shape analysis and determines various points of departure (PoD) metrics and the 'PROAST' package provides algorithms for dose-response modelling. The MutAIT statistical tools, which are currently being enhanced, provide users with an efficient and comprehensive platform to conduct quantitative dose-response analyses and determine PoD values that can then be used to calculate human exposure limits or margins of exposure.


Assuntos
Análise Mutacional de DNA/métodos , Bases de Dados de Ácidos Nucleicos , Mutagênicos/toxicidade , Mutação , Software , Toxicologia/métodos , Animais , Carcinógenos/toxicidade , Biologia Computacional/métodos , DNA/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Genética , Humanos , Masculino , Camundongos , Modelos Genéticos , Primatas/genética , Ratos
9.
Clin Transplant ; 30(9): 1108-14, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27327607

RESUMO

BACKGROUND: The role of anti-HLA-DP antibodies in renal transplantation is poorly defined. This study describes the impact of donor (donor-specific antibody [DSA]) and non-donor-specific antibodies against HLA-DP antigens in renal transplant patients. METHODS: Of 195 consecutive patients transplanted between September 2009 and December 2011, 166 primary kidney recipients and their donors were typed (high-resolution) for DP antigens. Sera taken pre-transplant and at 1, 3, 6, 9, and 12 months, and annually post-transplant were retrospectively tested for anti-DP antibodies using single-antigen beads. RESULTS: In 81 (49%) patients, anti-DP antibodies were found; 64% (n=52) of patients were positive in the pre-transplant samples and 36% (n=29) were positive exclusively post-transplant. The median time from transplantation to antibody was 20.9 months. Fifty-five percent (n=16) of the de novo anti-DP antibodies were accompanied by another de novo DSA. Anti-DP antibody-positive patients had a higher rate of rejection (compared with anti-DP antibody-negative patients, P=.01). The estimated glomerular filtration rate declined more with anti-DP antibodies (-5.5% vs +26%). CONCLUSIONS: Antibodies against HLA-DP antigens are common. De novo anti-DP antibodies commonly appear after acute rejection and accompany DSA, which makes it difficult to determine whether anti-DP antibodies are the cause or the consequence of graft injury.


Assuntos
Rejeição de Enxerto/imunologia , Antígenos HLA-DP/imunologia , Isoanticorpos/imunologia , Transplante de Rim , Doadores de Tecidos , Feminino , Seguimentos , Rejeição de Enxerto/epidemiologia , Sobrevivência de Enxerto/imunologia , Teste de Histocompatibilidade , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , North Carolina/epidemiologia , Estudos Retrospectivos
10.
J Clin Gastroenterol ; 50(1): 17-22, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25811111

RESUMO

GOALS: To develop a new nested polymerase chain reaction (PCR) assay for identifying Helicobacter pylori DNA from dental plaque. BACKGROUND: H. pylori is one of the most common chronic bacterial pathogens in humans. The accurate detection of this organism is essential for proper patient management and for the eradication of the bacteria following treatment. STUDY: Forty-nine patients (24 males and 25 females; mean age: 51; range, 19 to 94 y) were investigated for the presence of H. pylori in dental plaque by single-step PCR and nested PCR and in the stomach by single-step PCR, nested PCR, and histologic examination. RESULTS: The newly developed nested PCR assay identified H. pylori DNA in gastric biopsies of 18 patients who were histologically classified as H. pylori-positive and 2 additional biopsies of patients who were H. pylori-negative by histologic examination (20/49; 40.8%). Dental plaque samples collected before and after endoscopy from the 49 patients revealed that single-step PCR did not detect H. pylori but nested PCR was able to detect H. pylori DNA in 40.8% (20/49) patients. Nested PCR gave a higher detection rate (40.8%, 20/49) than that of histology (36.7%, 18/49) and single-step PCR. When nested PCR results were compared with histology results there was no significant difference between the 2 methods. CONCLUSIONS: Our newly developed nested PCR assay is at least as sensitive as histology and may be useful for H. pylori detection in patients unfit for endoscopic examination.


Assuntos
Placa Dentária/microbiologia , Infecções por Helicobacter/diagnóstico , Helicobacter pylori/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , DNA Bacteriano/isolamento & purificação , Feminino , Infecções por Helicobacter/microbiologia , Humanos , Masculino , Pessoa de Meia-Idade , Boca , Estômago/microbiologia , Adulto Jovem
11.
Dent Update ; 43(9): 849-50, 853-6, 858, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29152956

RESUMO

People with learning disabilities (LDs) have poorer health than their non-disabled peers due to failures in reasonable adjustments. One hundred patients with severe LD and challenging behaviour attended for dental treatment under GA, during which routine blood testing was provided. Communication with general medical practitioners (GMPs) and blood test results were evaluated, showing poor communication with GMPs and significant undiagnosed disease among this group. Blood tests generate similar costs in primary and secondary care but a holistic approach to care under GA reduces expenses brought by lost clinical time and resources due to complex behaviours in an out-patient setting. Clinical relevance: This article discusses a holistic approach to healthcare for people with severe LD, including patient outcomes, financial and resource implications, and offers practical guidance on venepuncture technique, which is relevant to many aspects of both community and hospital dental practice.


Assuntos
Anestesia Geral , Assistência Odontológica para a Pessoa com Deficiência , Deficiências da Aprendizagem , Flebotomia , Humanos , Índice de Gravidade de Doença
12.
Tumour Biol ; 36(6): 4861-9, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25631751

RESUMO

Increasingly, in castration-resistant prostate cancer, patients are often treated with docetaxel and the bisphosphonate zoledronic acid concurrently, yet there is still a paucity in the literature regarding the molecular basis of how this drug combination works. The study was performed on the hormone-resistant cell line PC-3. Cells were treated with clinically relevant concentrations of docetaxel and zoledronic acid either as single agents or in sequence and combination. Cell viability and apoptosis were assessed along with the prenylation status of the GTPases Ras and RhoA. Following 1-mM zoledronic acid treatment, inhibition of the prenylation of H-Ras and Rho A was observed along with an increase in the unprenylated form in the cytoplasm. Docetaxel 1 nM and zoledronic acid 1 mM also showed an increase in the unprenylated form of both small GTP-binding proteins in the cytoplasm and a reduction of protein in the membrane fraction. Overall, zoledronic acid followed by docetaxel was the best regimen producing the greatest reduction in cell viability and increase in apoptosis. At the highest concentrations of zoledronic acid and docetaxel, zoledronic acid followed by docetaxel was also the most effective at reducing the prenylation of both H-Ras and RhoA at the membrane. We have demonstrated that clinically achievable concentrations of zoledronic acid and docetaxel cause a reduction in the prenylation of both H-Ras and Rho A and a reduction of protein movement into the membrane. The most effective regimen overall was high-dose zoledronic acid followed by docetaxel, suggesting that this regimen may be of benefit in clinical practice.


Assuntos
Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/genética , Proteínas ras/biossíntese , Proteína rhoA de Ligação ao GTP/biossíntese , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Difosfonatos/administração & dosagem , Docetaxel , Regulação Neoplásica da Expressão Gênica , Humanos , Imidazóis/administração & dosagem , Masculino , Neoplasias da Próstata/patologia , Taxoides/administração & dosagem , Ácido Zoledrônico
13.
Mol Biol Evol ; 30(9): 2145-56, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23813979

RESUMO

Heterogeneity among life traits in mammals has resulted in considerable phylogenetic conflict, particularly concerning the position of the placental root. Layered upon this are gene- and lineage-specific variation in amino acid substitution rates and compositional biases. Life trait variations that may impact upon mutational rates are longevity, metabolic rate, body size, and germ line generation time. Over the past 12 years, three main conflicting hypotheses have emerged for the placement of the placental root. These hypotheses place the Atlantogenata (common ancestor of Xenarthra plus Afrotheria), the Afrotheria, or the Xenarthra as the sister group to all other placental mammals. Model adequacy is critical for accurate tree reconstruction and by failing to account for these compositional and character exchange heterogeneities across the tree and data set, previous studies have not provided a strongly supported hypothesis for the placental root. For the first time, models that accommodate both tree and data set heterogeneity have been applied to mammal data. Here, we show the impact of accurate model assignment and the importance of data sets in accommodating model parameters while maintaining the power to reject competing hypotheses. Through these sophisticated methods, we demonstrate the importance of model adequacy, data set power and provide strong support for the Atlantogenata over other competing hypotheses for the position of the placental root.


Assuntos
Evolução Molecular , Mamíferos/classificação , Modelos Genéticos , Filogenia , Substituição de Aminoácidos , Animais , Feminino , Heterogeneidade Genética , Mamíferos/genética , Taxa de Mutação , Placenta/fisiologia , Gravidez , Recombinação Genética
14.
Mamm Genome ; 25(11-12): 636-47, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25239304

RESUMO

Mitochondrial data have traditionally been used in reconstructing a variety of species phylogenies. The low rates of recombination and thorough characterization of mitochondrial data across vertebrate species make it a particularly attractive phylogenetic marker. The relatively low number of fully sequenced mammal genomes and the lack of extensive sampling within Superorders have posed a serious problem for reaching agreement on the placement mammal species. The use of mitochondrial data sequences from large numbers of mammals could serve to circumvent the taxon-sampling deficit. Here we assess the suitability of mitochondrial data as a phylogenetic marker in mammal phylogenetics. MtDNA datasets of mammal origin have been filtered as follows: (i) we have sampled sparsely across the phylogenetic tree, (ii) we have constrained our sampling to genes with high taxon coverage, (iii) we have categorised rates across sites in a phylogeny independent manner and have removed fast evolving sites, and (iv), we have sampled from very shallow divergence times to reduce phylogenetic conflict. However, topologies obtained using these filters are not consistent with previous studies and are discordant across different genes. Individual mitochondrial genes, and indeed all mitochondrial genes analysed as a supermatrix, resulted in poor resolution of the species phylogeny. Overall, our study highlights the limitations of mitochondrial data, not only for resolving deep divergences and but also for shallow divergences in the mammal phylogeny.


Assuntos
DNA Mitocondrial/genética , Animais , Evolução Molecular , Especiação Genética , Mamíferos/genética , Modelos Genéticos , Tipagem de Sequências Multilocus , Filogenia , Análise de Sequência de DNA
15.
J Surg Res ; 192(1): 1-5, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25151468

RESUMO

BACKGROUND: The Hemodialysis Reliable Outflow (HeRO) vascular access device is a hybrid polytetrafluoroethylene graft-stent construct designed to address central venous occlusive disease. Although initial experience has demonstrated excellent mid-term patency rates, subsequent studies have led to external validity questions. The purpose of this study was to examine a single center experience with this vascular access device in challenging access cases with associated costs. METHODS: A retrospective study representing the authors' cumulative HeRO vascular access device experience was undertaken. The primary endpoint was graft failure or death, with secondary endpoints including secondary intervention rates and cost. RESULTS: Forty-one patients with 15,579 HeRO days and a mean of 12.7 ± 1.5 mo with the vascular access device were available for analysis. Secondary patency was 81.6% at 6 mo and 53.7% at 12 mo. The reintervention rate was 2.84 procedures per HeRO vascular access device year. Associated HeRO costs related to subsequent procedures were estimated at $34,713.63 per patient/y. CONCLUSIONS: These data on the patency and primary outcome data diverge significantly from initial multicenter studies and represent a real-world application of this technology. It is costly to maintain patency. Use of HeRO vascular access devices should be judicious with outcome expectations reduced.


Assuntos
Derivação Arteriovenosa Cirúrgica/normas , Oclusão de Enxerto Vascular/prevenção & controle , Falência Renal Crônica/terapia , Diálise Renal/instrumentação , Dispositivos de Acesso Vascular/normas , Derivação Arteriovenosa Cirúrgica/economia , Feminino , Oclusão de Enxerto Vascular/economia , Oclusão de Enxerto Vascular/mortalidade , Gastos em Saúde/estatística & dados numéricos , Humanos , Estimativa de Kaplan-Meier , Falência Renal Crônica/economia , Falência Renal Crônica/mortalidade , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde/economia , Diálise Renal/economia , Diálise Renal/mortalidade , Estudos Retrospectivos , Dispositivos de Acesso Vascular/economia
16.
Front Psychiatry ; 15: 1383080, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38903648

RESUMO

Introduction: COVID-19 necessitated a rapid move from face-to-face services to remote care for eating disorders/eating distress (EDs). This study explores the advantages and challenges of remote care, identifying future implications for service provision. Remote care has been considered in the broadest of terms, including therapeutic care (e.g., Cognitive Behavioural Therapy, peer support, forums, one-to-one and group care options). Methods: Using a mixed methods approach, data were collected from 211 people with lived experience of EDs (PWLE), with and without formal diagnosis. 27 participants took part in semi-structured interviews/workshops and a further 184 participants took part via an online survey. Participants reported on their ED status, the impact of the pandemic on symptoms, the benefits, and challenges of remote care (and type of support accessed), and any reasons for not accessing support. Participants were invited to make future care recommendations. Results: ED symptoms were reported as worsening during the pandemic with contributing factors including isolation, lack of routine, negative emotions, and feeling like the external situation was outside of one's control. Remote care was positively attributed to increased flexibility and facilitation of social connection. Identified barriers to access included lack of awareness about support availability, digital access/literacy, and competing commitments. Further challenges included approaches being perceived as too clinical (e.g., ED information and support presented using clinical language and/or limited to support within medical care settings, without acknowledging the broader context of disordered eating), uncertainty around remote care quality, and concerns that remote platforms may facilitate masking of symptoms. Participants reported distress caused by online platforms where self-view is the default during video calls. They expressed a need for more holistic approaches to remote care, including: "real stories" of recovery, and hybrid (online and offline) options for greater flexibility and widening of access and choice. Participants also expressed a need for appropriate digital literacy training. Discussion: Future recommendations emphasise user-centred holistic and hybrid approaches to ED remote support, with training to address digital literacy barriers and facilitate user control of platform functionalities (e.g., self-view). This study underscores the need for continued remote care with a focus on inclusivity and user empowerment.

17.
Cell Biosci ; 14(1): 38, 2024 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-38521952

RESUMO

BACKGROUND: Bacterial cancer therapy was first trialled in patients at the end of the nineteenth century. More recently, tumour-targeting bacteria have been harnessed to deliver plasmid-expressed therapeutic interfering RNA to a range of solid tumours. A major limitation to clinical translation of this is the short-term nature of RNA interference in vivo due to plasmid instability. To overcome this, we sought to develop tumour-targeting attenuated bacteria that stably express shRNA by virtue of integration of an expression cassette within the bacterial chromosome and demonstrate therapeutic efficacy in vitro and in vivo. RESULTS: The attenuated tumour targeting Salmonella typhimurium SL7207 strain was modified to carry chromosomally integrated shRNA expression cassettes at the xylA locus. The colorectal cancer cell lines SW480, HCT116 and breast cancer cell line MCF7 were used to demonstrate the ability of these modified strains to perform intracellular infection and deliver effective RNA and protein knockdown of the target gene c-Myc. In vivo therapeutic efficacy was demonstrated using the Lgr5creERT2Apcflx/flx and BlgCreBrca2flx/flp53flx/flx orthotopic immunocompetent mouse models of colorectal and breast cancer, respectively. In vitro co-cultures of breast and colorectal cancer cell lines with modified SL7207 demonstrated a significant 50-95% (P < 0.01) reduction in RNA and protein expression with SL7207/c-Myc targeted strains. In vivo, following establishment of tumour tissue, a single intra-peritoneal administration of 1 × 106 CFU of SL7207/c-Myc was sufficient to permit tumour colonisation and significantly extend survival with no overt toxicity in control animals. CONCLUSIONS: In summary we have demonstrated that tumour tropic bacteria can be modified to safely deliver therapeutic levels of gene knockdown. This technology has the potential to specifically target primary and secondary solid tumours with personalised therapeutic payloads, providing new multi-cancer detection and treatment options with minimal off-target effects. Further understanding of the tropism mechanisms and impact on host immunity and microbiome is required to progress to clinical translation.

18.
Lancet Gastroenterol Hepatol ; 9(8): 694-704, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38823398

RESUMO

BACKGROUND: In the preplanned interim analysis of the TOPAZ-1 study, durvalumab plus gemcitabine-cisplatin significantly improved overall survival versus placebo plus gemcitabine-cisplatin in participants with advanced biliary tract cancer. We aimed to report updated overall survival and safety data from TOPAZ-1 with additional follow-up and data maturity beyond the interim analysis. METHODS: TOPAZ-1 was a phase 3, randomised, double-masked, placebo-controlled, global study done at 105 sites in 17 countries. Participants aged 18 years or older with unresectable, locally advanced, or metastatic biliary tract cancer were randomly assigned (1:1) to durvalumab plus gemcitabine-cisplatin or placebo plus gemcitabine-cisplatin using a computer-generated randomisation scheme, stratified by disease status and primary tumour location. Participants received durvalumab (1500 mg) or placebo on day 1 of each cycle every 3 weeks for up to eight cycles, plus gemcitabine (1000 mg/m2) and cisplatin (25 mg/m2) intravenously on days 1 and 8 of each cycle every 3 weeks for up to eight cycles, followed by durvalumab (1500 mg) or placebo monotherapy every 4 weeks until disease progression or other discontinuation criteria were met. Investigators and participants were masked to study treatment. The primary endpoint was overall survival. TOPAZ-1 met its primary endpoint at the preplanned interim analysis, and the study is active but no longer recruiting participants. Updated overall survival and safety data from TOPAZ-1, with additional follow-up (data cutoff Feb 25, 2022) and data maturity beyond the interim analysis, are reported here. Efficacy was assessed in the full analysis set (all randomly assigned participants). Safety was assessed in the safety analysis set (all participants who received at least one dose of study treatment). The TOPAZ-1 study is registered with ClinicalTrials.gov, NCT03875235. FINDINGS: From April 16, 2019, to Dec 11, 2020, 914 participants were enrolled, 685 of whom were randomly assigned (341 to the durvalumab plus gemcitabine-cisplatin group and 344 to the placebo plus gemcitabine-cisplatin group). 345 (50%) participants were male and 340 (50%) were female. Median follow-up at the updated data cutoff was 23·4 months (95% CI 20·6-25·2) in the durvalumab plus gemcitabine-cisplatin group and 22·4 months (21·4-23·8) in the placebo plus gemcitabine-cisplatin group. At the updated data cutoff, 248 (73%) participants in the durvalumab plus gemcitabine-cisplatin group and 279 (81%) participants in the placebo plus gemcitabine-cisplatin group had died (median overall survival 12·9 months [95% CI 11·6-14·1] vs 11·3 months [10·1-12·5]; hazard ratio 0·76 [95% CI 0·64-0·91]). Kaplan-Meier-estimated 24-month overall survival rates were 23·6% (95% CI 18·7-28·9) in the durvalumab plus gemcitabine-cisplatin group and 11·5% (7·6-16·2) in the placebo plus gemcitabine-cisplatin group. Maximum grade 3 or 4 adverse events occurred in 250 (74%) of 338 participants in the durvalumab plus gemcitabine-cisplatin group and 257 (75%) of 342 in the placebo plus gemcitabine-cisplatin group. The most common maximum grade 3 or 4 treatment-related adverse events were decreased neutrophil count (70 [21%] vs 86 [25%]), anaemia (64 [19%] vs 64 [19%]), and neutropenia (63 [19%] vs 68 [20%]). INTERPRETATION: Durvalumab plus gemcitabine-cisplatin showed robust and sustained overall survival benefit with no new safety signals. Findings continue to support the regimen as a standard of care for people with untreated, advanced biliary tract cancer. FUNDING: AstraZeneca.


Assuntos
Anticorpos Monoclonais , Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias do Sistema Biliar , Cisplatino , Desoxicitidina , Gencitabina , Humanos , Cisplatino/administração & dosagem , Cisplatino/uso terapêutico , Desoxicitidina/análogos & derivados , Desoxicitidina/administração & dosagem , Desoxicitidina/uso terapêutico , Neoplasias do Sistema Biliar/tratamento farmacológico , Neoplasias do Sistema Biliar/mortalidade , Neoplasias do Sistema Biliar/patologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Masculino , Feminino , Pessoa de Meia-Idade , Método Duplo-Cego , Idoso , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais/efeitos adversos , Adulto , Taxa de Sobrevida
19.
BMC Evol Biol ; 13: 251, 2013 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-24237966

RESUMO

BACKGROUND: Placental mammals display a huge range of life history traits, including size, longevity, metabolic rate and germ line generation time. Although a number of general trends have been proposed between these traits, there are exceptions that warrant further investigation. Species such as naked mole rat, human and certain bat species all exhibit extreme longevity with respect to body size. It has long been established that telomeres and telomere maintenance have a clear role in ageing but it has not yet been established whether there is evidence for adaptation in telomere maintenance proteins that could account for increased longevity in these species. RESULTS: Here we carry out a molecular investigation of selective pressure variation, specifically focusing on telomere associated genes across placental mammals. In general we observe a large number of instances of positive selection acting on telomere genes. Although these signatures of selection overall are not significantly correlated with either longevity or body size we do identify positive selection in the microbat species Myotis lucifugus in functionally important regions of the telomere maintenance genes DKC1 and TERT, and in naked mole rat in the DNA repair gene BRCA1. CONCLUSION: These results demonstrate the multifarious selective pressures acting across the mammal phylogeny driving lineage-specific adaptations of telomere associated genes. Our results show that regardless of the longevity of a species, these proteins have evolved under positive selection thereby removing increased longevity as the single selective force driving this rapid rate of evolution. However, evidence of molecular adaptations specific to naked mole rat and Myotis lucifugus highlight functionally significant regions in genes that may alter the way in which telomeres are regulated and maintained in these longer-lived species.


Assuntos
Quirópteros/genética , Ratos-Toupeira/genética , Telômero/genética , Adaptação Fisiológica , Envelhecimento/genética , Animais , Tamanho Corporal , Humanos , Longevidade/genética , Mamíferos/genética , Mamíferos/fisiologia , Filogenia , Seleção Genética
20.
Angiogenesis ; 16(3): 493-502, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23417553

RESUMO

Chronic diseases such as vascular disease and diabetes are witnessing a global increase in prevalence. Such diseases often predispose patients to the development of severe, debilitating, chronic wounds. Angiogenesis, the formation of new capillaries from the pre-existing vascular network, is an essential component of wound healing and aberrant angiogenesis is evident in almost all chronic wounds. Natural products, derived from both plants and animals, provide a significant haven of compounds which have proved to be of great benefit to man and his ailments. Whilst significant advances have been made in the understanding of impaired angiogenesis in a non-healing wound, in the clinical setting, few effective agents exist that can expedite wound healing and closure. The lack of effective healing agents has led to a renewed interest in investigations into natural wound healing resources. In this review, we collate new evidence that details the potential for several natural compounds to promote angiogenesis and wound healing, most predominately via the up regulation of VEGF expression, that warrant urgent further investigation for development into new pro-angiogenic/wound healing therapies.


Assuntos
Indutores da Angiogênese/farmacologia , Produtos Biológicos/farmacologia , Doença Crônica/tratamento farmacológico , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Neovascularização Fisiológica/efeitos dos fármacos , Cicatrização/fisiologia , Animais , Humanos , Insetos , Larva/metabolismo , Larva/fisiologia , Modelos Biológicos , Neovascularização Fisiológica/fisiologia , Fenóis/farmacologia , Extratos Vegetais/farmacologia
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