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BACKGROUND: Regional hyperthermia (RHT) with cisplatin added to gemcitabine showed efficacy in gemcitabine-pre-treated patients with advanced pancreatic ductal adenocarcinoma. We conducted a randomised clinical trial to investigate RHT with cisplatin added to gemcitabine (GPH) compared with gemcitabine (G) in the adjuvant setting of resected pancreatic ductal adenocarcinoma. METHODS: This randomised, multicentre, open-label trial randomly assigned patients to either GPH (gemcitabine 1000 mg/m2 on day 1, 15 and cisplatin 25 mg/m2 with RHT on day 2, 3 and 15,16) or to G (gemcitabine 1000 mg/m2 on day 1,8,15), four-weekly over six cycles. Disease-free survival (DFS) was the primary end-point. Secondary end-points included overall survival (OS) and safety. RESULTS: A total of 117 eligible patients (median age, 63 years) were randomly allocated to treatment (57 GPH; 60 G). With a follow-up time of 56.6 months, the median DFS was 12.7 compared to 11.2 months for GPH and G, respectively (p = 0.394). Median post-recurrence survival was significantly prolonged in the GPH-group (15.3 versus 9.8 months; p = 0.031). Median OS reached 33.2 versus 25.2 months (p = 0.099) with 5-year survival rates of 28.4% versus 18.7%. Excluding eight patients who received additional capecitabine in the G-arm (investigators choice), median OS favoured GPH (p = 0.052). Adverse events CTCAE (Common Terminology Criteria for Adverse Events) grade ≥3 occurred in 61.5% (GPH) versus 63.6% (G) of patients. Two patients in the G-group died because of treatment-related toxic effects. CONCLUSIONS: The randomised controlled Hyperthermia European Adjuvant Trial study failed to demonstrate a significant difference in DFS. However, it suggests a difference in post-recurrence survival and a trend for improved OS. CLINICALTRIALS: gov, number NCT01077427.
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Adenocarcinoma , Carcinoma Ductal Pancreático , Hipertermia Induzida , Neoplasias Pancreáticas , Humanos , Pessoa de Meia-Idade , Gencitabina , Cisplatino/efeitos adversos , Temperatura Alta , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carcinoma Ductal Pancreático/tratamento farmacológico , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/patologia , Adenocarcinoma/tratamento farmacológico , Neoplasias PancreáticasRESUMO
RNA-binding proteins (RBPs) play key roles in post-transcriptional regulation and disease. Their binding sites cover more of the genome than coding exons; nevertheless, most noncoding variant prioritization methods only focus on transcriptional regulation. Here, we integrate the portfolio of ENCODE-RBP experiments to develop RADAR, a variant-scoring framework. RADAR uses conservation, RNA structure, network centrality, and motifs to provide an overall impact score. Then, it further incorporates tissue-specific inputs to highlight disease-specific variants. Our results demonstrate RADAR can successfully pinpoint variants, both somatic and germline, associated with RBP-function dysregulation, which cannot be found by most current prioritization methods, for example, variants affecting splicing.
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Genômica/métodos , Processamento Pós-Transcricional do RNA/genética , Proteínas de Ligação a RNA/genética , Software , Neoplasias da Mama/genética , HumanosRESUMO
ENCODE comprises thousands of functional genomics datasets, and the encyclopedia covers hundreds of cell types, providing a universal annotation for genome interpretation. However, for particular applications, it may be advantageous to use a customized annotation. Here, we develop such a custom annotation by leveraging advanced assays, such as eCLIP, Hi-C, and whole-genome STARR-seq on a number of data-rich ENCODE cell types. A key aspect of this annotation is comprehensive and experimentally derived networks of both transcription factors and RNA-binding proteins (TFs and RBPs). Cancer, a disease of system-wide dysregulation, is an ideal application for such a network-based annotation. Specifically, for cancer-associated cell types, we put regulators into hierarchies and measure their network change (rewiring) during oncogenesis. We also extensively survey TF-RBP crosstalk, highlighting how SUB1, a previously uncharacterized RBP, drives aberrant tumor expression and amplifies the effect of MYC, a well-known oncogenic TF. Furthermore, we show how our annotation allows us to place oncogenic transformations in the context of a broad cell space; here, many normal-to-tumor transitions move towards a stem-like state, while oncogene knockdowns show an opposing trend. Finally, we organize the resource into a coherent workflow to prioritize key elements and variants, in addition to regulators. We showcase the application of this prioritization to somatic burdening, cancer differential expression and GWAS. Targeted validations of the prioritized regulators, elements and variants using siRNA knockdowns, CRISPR-based editing, and luciferase assays demonstrate the value of the ENCODE resource.
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Bases de Dados Genéticas , Genômica , Neoplasias/genética , Linhagem Celular Tumoral , Transformação Celular Neoplásica/genética , Redes Reguladoras de Genes , Humanos , Mutação/genética , Reprodutibilidade dos Testes , Fatores de Transcrição/metabolismoRESUMO
Mature adipocytes store fatty acids and are a common component of tissue stroma. Adipocyte function in regulating bone marrow, skin, muscle, and mammary gland biology is emerging, but the role of adipocyte-derived lipids in tissue homeostasis and repair is poorly understood. Here, we identify an essential role for adipocyte lipolysis in regulating inflammation and repair after injury in skin. Genetic mouse studies revealed that dermal adipocytes are necessary to initiate inflammation after injury and promote subsequent repair. We find through histological, ultrastructural, lipidomic, and genetic experiments in mice that adipocytes adjacent to skin injury initiate lipid release necessary for macrophage inflammation. Tamoxifen-inducible genetic lineage tracing of mature adipocytes and single-cell RNA sequencing revealed that dermal adipocytes alter their fate and generate ECM-producing myofibroblasts within wounds. Thus, adipocytes regulate multiple aspects of repair and may be therapeutic for inflammatory diseases and defective wound healing associated with aging and diabetes.
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Lipólise , Miofibroblastos , Adipócitos , Animais , Macrófagos , Camundongos , PeleRESUMO
AIM: Investigation of the compatibility of work and family life for physicians in the Munich metropolitan area. METHODS: Survey of a representative sample of 1,800 physicians using a questionnaire. RESULTS: Men were less satisfied (7% very satisfied vs. 21%) with compatibility between work and family life than women. The group least satisfied overall was hospital-based physicians (p=0.000, chi-square=122.75). Women rather than men cut back their career due to children, perceived their professional advancement as impaired, desisted from establishing private practice or quit hospital employment altogether. Respondents strove for flexible childcare and makeshift solution if the established service failed. Most did not have that at their disposal. Hospital-based physicians wished for predictable working hours, and would like to have a say in the structure of their schedule. For the majority this was not the case. While for 80% it would be important to participate in the definition of their working hours, this was only possible in 17%. 86% found the opportunity to work part-time important, but many doctors (more than 30%) did not have that option. The biggest help for office-based physicians would be an expedited procedure by the Bavarian Association of Statutory Health Insurance Physicians (KVB) when applying for a proxy. The second most important would be the ability to hand over on-call duties. 36% of respondents felt that compatibility of work and family life was best achieved outside of patient care, during residency 42% believed this to be the case. Only 6% of physicians felt the best compatibility to be achieved in a hospital. Among the physician owners of practices, 34% considered their model to be the best way to reconcile both aspects of life. CONCLUSION: More flexible options for childcare and more influence on the definition of working hours are necessary in order to better reconcile work and family life. For office-based physicians it must be made easier to find a substitute. Currently, especially women consider children as hindering their careers. Hospitals are perceived as extremely unfavorable workplaces for achieving compatibility between work and family life.
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Emprego , Satisfação no Emprego , Médicos , Criança , Feminino , Alemanha , Humanos , Internato e Residência , Masculino , Inquéritos e QuestionáriosRESUMO
Chemical probing has the power to provide insight into RNA conformation in vivo and in vitro, but interpreting the results depends on methods to detect the chemically modified nucleotides. Traditionally, the presence of modified bases was inferred from their ability to halt reverse transcriptase during primer extension and the locations of termination sites observed by electrophoresis or sequencing. More recently, modification-induced mutations have been used as a readout for chemical probing data. Given the variable propensity for mismatch incorporation and read-through with different reverse transcriptases, we examined how termination and mutation events compare to each other in the same chemical probing experiments. We found that mutations and terminations induced by dimethyl sulfate probing are both specific for methylated bases, but these two measures have surprisingly little correlation and represent largely nonoverlapping indicators of chemical modification data. We also show that specific biases for modified bases depend partly on local sequence context and that different reverse transcriptases show different biases toward reading a modification as a stop or a mutation. These results support approaches that incorporate analysis of both termination and mutation events into RNA probing experiments.
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Fibroblastos/metabolismo , DNA Polimerase Dirigida por RNA/metabolismo , RNA/química , Animais , Células Cultivadas , Regulação Enzimológica da Expressão Gênica , Camundongos , Mutação , DNA Polimerase Dirigida por RNA/químicaRESUMO
BACKGROUND: Lifestyle factors play a pivotal role in the primary and tertiary prevention of colorectal cancer. The purpose of this review article is to summarize data concerning the effect of the lifestyle factors physical activity (PA) and nutrition in primary and, more importantly, tertiary prevention of colorectal cancer (CRC). METHODS: Focusing on the influence of lifestyle factors on prognosis und quality of life (QOL), a comprehensive literature search of clinical studies published mainly in the years 2000 until 2015 was performed and the current knowledge based on these clinical studies reviewed. RESULTS: Besides avoiding risk factors (such as smoking and overindulgence in alcohol), healthy weight, regular and moderate PA as well as a diet which contains fruit, vegetables, poultry, and fish (so-called 'Mediterranean' diet) may reduce the risk of the disease significantly. Patients already diagnosed with CRC can also actively improve the prognosis of CRC and QOL by changing their lifestyle. Patients commencing moderate exercise and modifying their eating habits in terms of a 'Mediterranean' diet can reduce cancer-specific and overall mortality by up to 40% and significantly increase their quality of life already during chemotherapy. Therefore, moderate physical exercise, calorie restriction, and a Mediterranean dietary pattern for patients with CRC should be recommended by physicians treating these patients. In fact, the World Cancer Research Fund/American Institute for Cancer Research (AICR/WCRF) systematic literature review from 2007 shows that the lifestyle changes recommended after diagnosis are the same for primary prevention of this disease. CONCLUSION: Lifestyle changes such as moderate PA and a Mediterranean diet significantly improve the QOL as well as the prognosis of patients suffering from colorectal disease. However, the effect of lifestyle changes is mostly based on observational studies, while only few studies are prospective and none are randomized. Therefore, these observational studies warrant controlled randomized trials to prove the effectiveness of lifestyle interventions on QOL and cancer recurrence.
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Beyond coding for proteins, RNA molecules have well-established functions in the posttranscriptional regulation of gene expression. Less clear are the upstream roles of RNA in regulating transcription and chromatin-based processes in the nucleus. RNA is transcribed in the nucleus, so it is logical that RNA could play diverse and broad roles that would impact human physiology. Indeed, this idea is supported by well-established examples of noncoding RNAs that affect chromatin structure and function. There has been dramatic growth in studies focused on the nuclear roles of long noncoding RNAs (lncRNAs). Although little is known about the biochemical mechanisms of these lncRNAs, there is a developing consensus regarding the challenges of defining lncRNA function and mechanism. In this review, we examine the definition, discovery, functions, and mechanisms of lncRNAs. We emphasize areas where challenges remain and where consensus among laboratories has underscored the exciting ways in which human lncRNAs may affect chromatin biology.
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Núcleo Celular/genética , Cromatina/genética , RNA Longo não Codificante/genética , Regulação da Expressão Gênica , HumanosRESUMO
The long non-coding RNA (lncRNA) Xist is a master regulator of X-chromosome inactivation in mammalian cells. Models for how Xist and other lncRNAs function depend on thermodynamically stable secondary and higher-order structures that RNAs can form in the context of a cell. Probing accessible RNA bases can provide data to build models of RNA conformation that provide insight into RNA function, molecular evolution, and modularity. To study the structure of Xist in cells, we built upon recent advances in RNA secondary structure mapping and modeling to develop Targeted Structure-Seq, which combines chemical probing of RNA structure in cells with target-specific massively parallel sequencing. By enriching for signals from the RNA of interest, Targeted Structure-Seq achieves high coverage of the target RNA with relatively few sequencing reads, thus providing a targeted and scalable approach to analyze RNA conformation in cells. We use this approach to probe the full-length Xist lncRNA to develop new models for functional elements within Xist, including the repeat A element in the 5'-end of Xist. This analysis also identified new structural elements in Xist that are evolutionarily conserved, including a new element proximal to the C repeats that is important for Xist function.
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Evolução Molecular , Conformação de Ácido Nucleico , RNA Longo não Codificante/genética , Inativação do Cromossomo X/genética , Animais , Metilação de DNA/genética , Humanos , Camundongos , Mutação Puntual/genética , Dobramento de RNA/genética , RNA Ribossômico/genética , Alinhamento de Sequência , Análise de Sequência de RNA , Cromossomo X/genéticaRESUMO
We describe a chemical method to label and purify 4-thiouridine (s(4)U)-containing RNA. We demonstrate that methanethiosulfonate (MTS) reagents form disulfide bonds with s(4)U more efficiently than the commonly used HPDP-biotin, leading to higher yields and less biased enrichment. This increase in efficiency allowed us to use s(4)U labeling to study global microRNA (miRNA) turnover in proliferating cultured human cells without perturbing global miRNA levels or the miRNA processing machinery. This improved chemistry will enhance methods that depend on tracking different populations of RNA, such as 4-thiouridine tagging to study tissue-specific transcription and dynamic transcriptome analysis (DTA) to study RNA turnover.
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MicroRNAs/química , Biotina/análogos & derivados , Proliferação de Células , Dissulfetos , Perfilação da Expressão Gênica/métodos , Células HEK293 , Humanos , Indicadores e Reagentes , Mesilatos , MicroRNAs/genética , MicroRNAs/metabolismo , Fenômenos de Química Orgânica , Processamento Pós-Transcricional do RNA , Tiouridina/químicaRESUMO
OBJECTIVE: To determine whether circular plastic wound edge protectors (CWEPs) significantly reduce the rate of surgical site infections (SSIs) in comparison to standard surgical towels in patients undergoing laparotomy. BACKGROUND: SSIs cause substantial morbidity, prolonged hospitalization, and costs and remain one of the most frequent surgical complications. CWEPs have been proposed as a measure to reduce the incidence of SSIs. METHODS: In this randomized controlled, multicenter, 2-arm, parallel-group design, patient- and observer-blinded trial patients undergoing open elective abdominal surgery were assigned to either intraoperative wound coverage with a CWEP or standard coverage with surgical towels. Primary endpoint was superiority of intervention over control in terms of the incidence of SSIs within a 30-day postoperative period. RESULTS: Between September 2010 and November 2012, 608 patients undergoing laparotomy were randomized at 16 centers across Germany. Three patients in the device group and 11 patients in the control group did not undergo laparotomy. Patients' and procedural characteristics were well balanced between the 2 groups. Forty-eight patients discontinued the study prematurely, mainly because of relaparotomy (control, n=9; intervention, n=9) and death (control, n=4; intervention, n=7). A total of 79 patients experienced SSIs within 30 days of surgery, 27 of 274 (9.9%) in the device group and 52 of 272 (19.1%) in the control group (odds ratio=0.462, 95% confidence interval: 0.281-0.762; P=0.002). Subgroup analyses indicate that the effect could be more pronounced in colorectal surgery, and in clean-contaminated/contaminated surgeries. CONCLUSIONS: Our trial shows that CWEPs are effective at reducing the incidence of SSIs in elective and clean or clean-contaminated open abdominal surgery.
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Técnicas de Fechamento de Ferimentos Abdominais , Bandagens , Infecção da Ferida Cirúrgica/prevenção & controle , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos Clínicos , Método Duplo-Cego , Feminino , Alemanha/epidemiologia , Humanos , Incidência , Laparotomia , Masculino , Pessoa de Meia-Idade , Polietileno , Fatores de Risco , Infecção da Ferida Cirúrgica/epidemiologia , Resultado do TratamentoRESUMO
Pseudogenes are degraded fossil copies of genes. Here, we report a comparison of pseudogenes spanning three phyla, leveraging the completed annotations of the human, worm, and fly genomes, which we make available as an online resource. We find that pseudogenes are lineage specific, much more so than protein-coding genes, reflecting the different remodeling processes marking each organism's genome evolution. The majority of human pseudogenes are processed, resulting from a retrotranspositional burst at the dawn of the primate lineage. This burst can be seen in the largely uniform distribution of pseudogenes across the genome, their preservation in areas with low recombination rates, and their preponderance in highly expressed gene families. In contrast, worm and fly pseudogenes tell a story of numerous duplication events. In worm, these duplications have been preserved through selective sweeps, so we see a large number of pseudogenes associated with highly duplicated families such as chemoreceptors. However, in fly, the large effective population size and high deletion rate resulted in a depletion of the pseudogene complement. Despite large variations between these species, we also find notable similarities. Overall, we identify a broad spectrum of biochemical activity for pseudogenes, with the majority in each organism exhibiting varying degrees of partial activity. In particular, we identify a consistent amount of transcription (â¼15%) across all species, suggesting a uniform degradation process. Also, we see a uniform decay of pseudogene promoter activity relative to their coding counterparts and identify a number of pseudogenes with conserved upstream sequences and activity, hinting at potential regulatory roles.
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Caenorhabditis elegans/genética , Drosophila melanogaster/genética , Filogenia , Pseudogenes/genética , Animais , Evolução Molecular , Estudos de Associação Genética , Humanos , Anotação de Sequência Molecular , Regiões Promotoras Genéticas/genética , Homologia de Sequência do Ácido NucleicoRESUMO
We use first-principles density functional theory within the local density approximation to ascertain the ground state structure of real and theoretical compounds with the formula ABS3 (A = K, Rb, Cs, Ca, Sr, Ba, Tl, Sn, Pb, and Bi; and B = Sc, Y, Ti, Zr, V, and Nb) under the constraint that B must have a d(0) electronic configuration. Our findings indicate that none of these AB combinations prefer a perovskite ground state with corner-sharing BS6 octahedra, but that they prefer phases with either edge- or face-sharing motifs. Further, a simple two-dimensional structure field map created from A and B ionic radii provides a neat demarcation between combinations preferring face-sharing versus edge-sharing phases for most of these combinations. We then show that by modifying the common Goldschmidt tolerance factor with a multiplicative term based on the electronegativity difference between A and S, the demarcation between predicted edge-sharing and face-sharing ground state phases is enhanced. We also demonstrate that, by calculating the free energy contribution of phonons, some of these compounds may assume multiple phases as synthesis temperatures are altered, or as ambient temperatures rise or fall.
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The Xist long noncoding RNA (lncRNA) is essential for X-chromosome inactivation (XCI), the process by which mammals compensate for unequal numbers of sex chromosomes. During XCI, Xist coats the future inactive X chromosome (Xi) and recruits Polycomb repressive complex 2 (PRC2) to the X-inactivation centre (Xic). How Xist spreads silencing on a 150-megabases scale is unclear. Here we generate high-resolution maps of Xist binding on the X chromosome across a developmental time course using CHART-seq. In female cells undergoing XCI de novo, Xist follows a two-step mechanism, initially targeting gene-rich islands before spreading to intervening gene-poor domains. Xist is depleted from genes that escape XCI but may concentrate near escapee boundaries. Xist binding is linearly proportional to PRC2 density and H3 lysine 27 trimethylation (H3K27me3), indicating co-migration of Xist and PRC2. Interestingly, when Xist is acutely stripped off from the Xi in post-XCI cells, Xist recovers quickly within both gene-rich and gene-poor domains on a timescale of hours instead of days, indicating a previously primed Xi chromatin state. We conclude that Xist spreading takes distinct stage-specific forms. During initial establishment, Xist follows a two-step mechanism, but during maintenance, Xist spreads rapidly to both gene-rich and gene-poor regions.
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RNA Longo não Codificante/metabolismo , Inativação do Cromossomo X , Cromossomo X/metabolismo , Animais , Cromatina/genética , Cromatina/metabolismo , Células-Tronco Embrionárias/metabolismo , Feminino , Fibroblastos/metabolismo , Inativação Gênica , Genes , Histona-Lisina N-Metiltransferase/metabolismo , Histonas/química , Histonas/metabolismo , Lisina/metabolismo , Metilação , Camundongos , Modelos Genéticos , RNA Longo não Codificante/genética , Cromossomo X/genética , Inativação do Cromossomo X/genéticaRESUMO
BACKGROUND: The aim of this study was to compare single-port access cholecystectomy (SPA) with the standard laparoscopic technique (LC) regarding the duration of the operation, complications, learning curve, late postoperative quality of life (QoL) and the incidence of incisional hernias. METHODS: Between June 2009 and December 2011, a total of 122 SPA cholecystectomies were performed in our hospital. Simultaneously, 310 patients were operated on with the LC technique. In the LC group, 100 patients met the same criteria defined for SPA surgery. The two groups (SPA and LC) were compared by multivariable regression analysis. Endpoints of this study were quality of life (QoL) after 6 months by the EQ-5D questionnaire 5L and the incidence of incisional hernia 1 year after surgery. Operating time, hospital stay, and perioperative complications were also measured and compared. The median follow-up was 9.2 months (3-25 months). RESULTS: The patients in the SPA group were younger and more often female. The mean operating time for group SPA was 73 min (35-136 min)-significantly longer than that for group LC with 60 min (33-190 min) (p < 0.001). Additional trocars were used in 8 of 122 (6.5 %) SPA patients. A conversion to open cholecystectomy was not necessary in SPA patients. The conversion rate in the LC group to open cholecystectomy was 2 % (2/100). The perioperative and postoperative complications and incisional hernia (5.5 %) were the same in both groups. QoL was significantly better in the SPA group in terms of mobility (p = 0,002), usual activity (p = 0.036), and overall anxiety (p = 0.026). CONCLUSIONS: SPA cholecystectomy is safe, although the operation is significantly longer. No differences in terms of major complications or the incidence of incisional hernia were seen after 1 year. QoL was significantly better in patients operated on with the SPA technique.
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Colecistectomia Laparoscópica/métodos , Doenças da Vesícula Biliar/cirurgia , Adolescente , Adulto , Idoso , Feminino , Seguimentos , Hérnia Ventral/epidemiologia , Hérnia Ventral/etiologia , Humanos , Curva de Aprendizado , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Duração da Cirurgia , Distribuição de Poisson , Complicações Pós-Operatórias/epidemiologia , Estudos Prospectivos , Qualidade de Vida , Inquéritos e Questionários , Resultado do Tratamento , Adulto JovemRESUMO
BACKGROUND/AIMS: To investigate the clinical features and rates of progression of conditions that are not considered to be normal, but do not fulfill criteria for mild cognitive impairment (MCI). METHODS: We longitudinally evaluated 269 elderly subjects who did not meet formal criteria for MCI at baseline but had: (1) a clinical history suggesting MCI without neuropsychological deficits (PreMCI-Clinical); or (2) neuropsychological deficits on one or more memory measures in conjunction with a negative clinical examination (amnestic PreMCI-NP) or were normal on both neuropsychological and clinical examination. RESULTS: The rate of progression to MCI or dementia over an average of 2- to 3 years was 3.7% for no cognitive impairment subjects, whereas it was significantly greater for all PreMCI subtypes (22.0% for PreMCI-Clinical, 38.9% for amnestic PreMCI-NP subjects with two or more memory impairments). Among PreMCI subjects as a whole, lower baseline scores on object memory and category fluency tests were the best predictors of progression to MCI or dementia. Cardiovascular risk factors, Parkinsonian symptoms, and hippocampal atrophy were not associated with progression. CONCLUSION: Distinct PreMCI subtypes defined on the basis of clinical and neuropsychological evaluations were found to have distinct characteristics, but both subtypes demonstrated elevated risk for progression to MCI or dementia. Despite the lack of evidence of clinical impairment, subjects with neuropsychological deficits in two memory domains were particularly at increased risk for progression of their deficits.
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Disfunção Cognitiva/classificação , Disfunção Cognitiva/diagnóstico , Idoso , Amnésia/diagnóstico , Amnésia/etiologia , Doenças Cardiovasculares , Disfunção Cognitiva/fisiopatologia , Progressão da Doença , Humanos , Estudos Longitudinais , Imageamento por Ressonância Magnética , Transtornos da Memória/diagnóstico , Transtornos da Memória/etiologia , Pessoa de Meia-Idade , Testes Neuropsicológicos , Escalas de Graduação Psiquiátrica , Estudos Retrospectivos , Fatores de RiscoRESUMO
The use of isolated human liver cells in research and development has gained increasing interest during the past years. The possible application may vary between elucidation of new biochemical pathways in liver diseases, drug development, safety issues, and new therapeutic strategies up to direct clinical translation for liver support. However, the isolation of human liver cells requires a well-developed logistic network among surgeons, biologists, and technicians to obtain a high quality of cells. Our laboratories have been involved in various applications of human liver cells and we have long-lasting experiences in human liver cell isolation and their application in R&D. We here summarize the present protocol of our laboratories for cell isolation from normal resected liver tissue, the most common tissue available. In addition, we discuss the necessary network in the clinic and quality controls to maintain human liver cells in culture and the effect of 3D extracellular matrix in cultured cells which results in preservation of hepatocyte epithelial polarity in the form of bile canaliculi and repression of epithelial to mesenchymal transitions occurring in 2D cultures.
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Separação Celular/métodos , Hepatócitos/citologia , Cultura Primária de Células/métodos , Cultura Primária de Células/normas , Células Cultivadas , Hepatócitos/enzimologia , Hepatócitos/metabolismo , Humanos , Controle de QualidadeRESUMO
We investigate the effect of ferroelectric polarization direction on the geometric properties of Pd deposited on the positive and negative surfaces of LiNbO(3) (0001). We predict preferred geometries and diffusion properties of small Pd clusters using density functional theory, and use these calculations as the basis for kinetic Monte Carlo simulations of Pd deposition on a larger scale. Our results show that on the positive surface, Pd atoms favor a clustered configuration, while on the negative surface, Pd atoms are adsorbed in a more dispersed pattern due to suppression of diffusion and agglomeration. This suggests that the effect of LiNbO(3) polarization direction on the catalytic activity of Pd [J. Phys. Chem. 88, 1148 (1984)] is due, at least in part, to differences in adsorption geometry. Further investigations using these methods can aid the search for catalysts whose activities switch reversibly with the polarization of their ferroelectric substrates.
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OBJECTIVE: To compare clinical, imaging, and neuropsychological characteristics and longitudinal course of subjects with pre-mild cognitive impairment (pre-MCI), who exhibit features of MCI on clinical examination but lack impairment on neuropsychological examination, to subjects with no cognitive impairment (NCI), nonamnestic MCI (naMCI), amnestic MCI (aMCI), and mild dementia. METHODS: For 369 subjects, clinical dementia rating sum of boxes (CDR-SB), ApoE genotyping, cardiovascular risk factors, parkinsonism (UPDRS) scores, structural brain MRIs, and neuropsychological testing were obtained at baseline, whereas 275 of these subjects received an annual follow-up for 2-3 years. RESULTS: At baseline, pre-MCI subjects showed impairment on tests of executive function and language, higher apathy scores, and lower left hippocampal volumes (HPCV) in comparison to NCI subjects. Pre-MCI subjects showed less impairment on at least one memory measure, CDR-SB and UPDRS scores, in comparison to naMCI, aMCI and mild dementia subjects. Follow-up over 2-3 years showed 28.6% of pre-MCI subjects, but less than 5% of NCI subjects progressed to MCI or dementia. Progression rates to dementia were equivalent between naMCI (22.2%) and aMCI (34.5%) groups, but greater than for the pre-MCI group (2.4%). Progression to dementia was best predicted by the CDR-SB, a list learning and executive function test. CONCLUSION: This study demonstrates that clinically defined pre-MCI has cognitive, functional, motor, behavioral and imaging features that are intermediate between NCI and MCI states at baseline. Pre-MCI subjects showed accelerated rates of progression to MCI as compared to NCI subjects, but slower rates of progression to dementia than MCI subjects.
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Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/patologia , Disfunção Cognitiva/psicologia , Progressão da Doença , Hipocampo/patologia , Testes Neuropsicológicos/estatística & dados numéricos , Idoso , Idoso de 80 Anos ou mais , Apolipoproteínas E/genética , Atrofia/patologia , Demência/complicações , Demência/patologia , Demência/psicologia , Diagnóstico Precoce , Feminino , Seguimentos , Genótipo , Humanos , Imageamento por Ressonância Magnética/métodos , Imageamento por Ressonância Magnética/psicologia , Masculino , Pessoa de Meia-Idade , Neuroimagem/métodos , Neuroimagem/psicologia , Transtornos Parkinsonianos/complicações , Transtornos Parkinsonianos/patologia , Transtornos Parkinsonianos/psicologia , Valor Preditivo dos Testes , Escalas de Graduação Psiquiátrica/estatística & dados numéricos , Fatores de RiscoRESUMO
Cognitive change following bilateral subthalamic nucleus (STN) deep brain stimulation (DBS) surgery in those with Parkinson's disease (PD) has led to equivocal results. The current study applied a standardized regression-based (SRB) method based on 20 medically managed PD patients and 20 STN DBS PD surgical patients who were administered the Repeatable Battery of Neuropsychological Status (RBANS). Of the medically managed PD participants, 94% remained stable compared to 73% of the DBS group. In the DBS group cognitive change was noted on the Total scale and the Immediate Memory Index. A secondary analysis also revealed reliable change on several subtest scores. Although preliminary, the current study provides change parameters for post DBS surgery on this brief battery.