983 resultados para Biology, Molecular|Health Sciences, Medicine and Surgery


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Wilms tumor (WT) is an embryonal renal tumor with a heterogeneous genetic etiology that serves as a valuable model for studying tumorigenesis. Biallelic inactivation of the tumor suppressor gene WT1, a zinc-finger transcriptional regulator located at 11p13, is critical for the development of some Wilms tumors. Interestingly, WT1 genomic analysis has demonstrated mutations in less than 20% of WT cases. This suggests either other genes play a more major role in Wilms tumorigenesis or WT1 is functionally altered by mechanisms other than DNA mutation. Previous observations in rat and in WT xenograft cell lines have suggested that abnormal WT1 RNA processing (exon 6 RNA editing and aberrant exon 2 splicing, respectively) is a potential mechanism of altering WT1 function in the absence of a WT1 DNA mutation. However, the role of this abnormal RNA processing has not previously been assessed in primary Wilms tumors. ^ To test the hypothesis that abnormal WT1 RNA processing is a mechanism of WT1alteration during tumor development, WT1 RNA from 85 primary tumors was analyzed using reverse transcription and polymerase chain reaction amplification (RT-PCR). Although no evidence for WT1 RNA editing was observed, variable levels (5% to 50%) of aberrant WT1 exon 2 splicing were detected for 11 tumors in the absence of a detectable WT1 DNA mutation. Also, alteration of normal WT1 alternative splicing, observed as RNA isoform loss, was detected in five tumors with no apparent WT1 genomic alteration, although no consistent pattern of RNA isoform loss was detected. This abnormal WT1 splicing, detected by either loss of exon 2 from some of the transcripts or loss of RNA isoforms, is statistically correlated with relapse (p = 0.005). These studies demonstrate that abnormal WT1 RNA processing is not a common mechanism of abrogating normal WT1 function in primary tumors. However, in those cases in which abnormal WTI splicing is present, these data indicate that it may serve as a useful prognostic marker for relapse in WT patients. ^

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STUDY QUESTION To what extent do the management of endometriosis and the symptoms that remain after treatment affect the quality of life in women with the disease? SUMMARY ANSWER Many women with endometriosis had impaired quality of life and continued to suffer from endometriosis-associated symptoms even though their endometriosis has been managed in tertiary care centres. WHAT IS KNOWN ALREADY The existing literature indicates that quality of life and work productivity is reduced in women with endometriosis. However, most studies have small sample sizes, are treatment related or examine newly diagnosed patients only. STUDY DESIGN, SIZE, DURATION A cross-sectional questionnaire-based survey among 931 women with endometriosis treated in 12 tertiary care centres in 10 countries. PARTICIPANTS/MATERIALS, SETTING, METHODS Women diagnosed with endometriosis who had at least one contact related to endometriosis-associated symptoms during 2008 with a participating centre were enrolled into the study. The study investigated the effect of endometriosis on education, work and social wellbeing, endometriosis-associated symptoms and health-related quality of life, by using questions obtained from the World Endometriosis Research Foundation (WERF) GSWH instrument (designed and validated for the WERF Global Study on Women's Health) and the Short Form 36 version 2 (SF-36v2). MAIN RESULTS AND THE ROLE OF CHANCE Of 3216 women invited to participate in the study, 1450 (45%) provided informed consent and out of these, 931 (931/3216 = 29%) returned the questionnaires. Endometriosis had affected work in 51% of the women and affected relationships in 50% of the women at some time during their life. Dysmenorrhoea was reported by 59%, dyspareunia by 56% and chronic pelvic pain by 60% of women. Quality of life was decreased in all eight dimensions of the SF-36v2 compared with norm-based scores from a general US population (all P < 0.01). Multivariate regression analysis showed that number of co-morbidities, chronic pain and dyspareunia had an independent negative effect on both the physical and mental component of the SF-36v2. LIMITATIONS, REASONS FOR CAUTION The fact that women were enrolled in tertiary care centres could lead to a possible over-representation of women with moderate-to-severe endometriosis, because the participating centres typically treat more complex and referred cases of endometriosis. The response rate was relatively low. Since there was no Institute Review Board approval to do a non-responder investigation on basic characteristics, some uncertainty remains regarding the representativeness of the investigated population. WIDER IMPLICATIONS OF THE FINDINGS This international multicentre survey represents a large group of women with endometriosis, in all phases of the disease, which increases the generalizability of the data. Women still suffer from frequent symptoms, despite tertiary care management, in particular chronic pain and dyspareunia. As a result their quality of life is significantly decreased. A patient-centred approach with extensive collaboration across disciplines, such as pain specialists, psychologists, sexologists and social workers, may be a valuable strategy to improve the long-term care of women with endometriosis. STUDY FUNDING/COMPETING INTEREST(S) The WERF EndoCost study is funded by the World Endometriosis Research Foundation (WERF) through grants received from Bayer Schering Pharma AG, Takeda Italia Farmaceutici SpA, Pfizer Ltd and the European Society of Human Reproduction and Embryology. The sponsors did not have a role in the design and conduct of the study; collection, management, analysis and interpretation of the data; and preparation, review or approval of the manuscript. L.H. is the chief executive and T.D. was a board member of WERF at the time of funding. T.D. holds the Merck-Serono Chair in Reproductive Medicine and Surgery, and the Ferring Chair in Reproductive Medicine at the Katholieke Universiteit Leuven in Belgium and has served as consultant/research collaborator for Merck-Serono, Schering-Plough, Astellas and Arresto.

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Although research and clinical interventions for patients with dual disorders have been described since as early as the 1980s, the day-to-day treatment of these patients remains problematic and challenging in many countries. Throughout this book, many approaches and possible pathways have been outlined. Based upon these experiences, some key points can be extracted in order to guide to future developments. (1) New diagnostic approaches are warranted when dealing with patients who have multiple problems, given the limitations of the current categorical systems. (2) Greater emphasis should be placed on secondary prevention and early intervention for children and adolescents at an increased risk of later-life dual disorders. (3) Mental, addiction, and somatic care systems can be integrated, adopting a patient-focused approach to care delivery. (4) Recovery should be taken into consideration when defining treatment intervention and outcome goals. (5) It is important to reduce societal risk factors, such as poverty and early childhood adversity. (6) More resources are needed to provide adequate mental health care in the various countries. The development of European guidance initiatives would provide benefits in many of these areas, making it possible to ensure a more harmonized standard of care for patients with dual disorders.

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BACKGROUND Record linkage of existing individual health care data is an efficient way to answer important epidemiological research questions. Reuse of individual health-related data faces several problems: Either a unique personal identifier, like social security number, is not available or non-unique person identifiable information, like names, are privacy protected and cannot be accessed. A solution to protect privacy in probabilistic record linkages is to encrypt these sensitive information. Unfortunately, encrypted hash codes of two names differ completely if the plain names differ only by a single character. Therefore, standard encryption methods cannot be applied. To overcome these challenges, we developed the Privacy Preserving Probabilistic Record Linkage (P3RL) method. METHODS In this Privacy Preserving Probabilistic Record Linkage method we apply a three-party protocol, with two sites collecting individual data and an independent trusted linkage center as the third partner. Our method consists of three main steps: pre-processing, encryption and probabilistic record linkage. Data pre-processing and encryption are done at the sites by local personnel. To guarantee similar quality and format of variables and identical encryption procedure at each site, the linkage center generates semi-automated pre-processing and encryption templates. To retrieve information (i.e. data structure) for the creation of templates without ever accessing plain person identifiable information, we introduced a novel method of data masking. Sensitive string variables are encrypted using Bloom filters, which enables calculation of similarity coefficients. For date variables, we developed special encryption procedures to handle the most common date errors. The linkage center performs probabilistic record linkage with encrypted person identifiable information and plain non-sensitive variables. RESULTS In this paper we describe step by step how to link existing health-related data using encryption methods to preserve privacy of persons in the study. CONCLUSION Privacy Preserving Probabilistic Record linkage expands record linkage facilities in settings where a unique identifier is unavailable and/or regulations restrict access to the non-unique person identifiable information needed to link existing health-related data sets. Automated pre-processing and encryption fully protect sensitive information ensuring participant confidentiality. This method is suitable not just for epidemiological research but also for any setting with similar challenges.

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BACKGROUND Potentially avoidable risk factors continue to cause unnecessary disability and premature death in older people. Health risk assessment (HRA), a method successfully used in working-age populations, is a promising method for cost-effective health promotion and preventive care in older individuals, but the long-term effects of this approach are unknown. The objective of this study was to evaluate the effects of an innovative approach to HRA and counselling in older individuals for health behaviours, preventive care, and long-term survival. METHODS AND FINDINGS This study was a pragmatic, single-centre randomised controlled clinical trial in community-dwelling individuals aged 65 y or older registered with one of 19 primary care physician (PCP) practices in a mixed rural and urban area in Switzerland. From November 2000 to January 2002, 874 participants were randomly allocated to the intervention and 1,410 to usual care. The intervention consisted of HRA based on self-administered questionnaires and individualised computer-generated feedback reports, combined with nurse and PCP counselling over a 2-y period. Primary outcomes were health behaviours and preventive care use at 2 y and all-cause mortality at 8 y. At baseline, participants in the intervention group had a mean ± standard deviation of 6.9 ± 3.7 risk factors (including unfavourable health behaviours, health and functional impairments, and social risk factors) and 4.3 ± 1.8 deficits in recommended preventive care. At 2 y, favourable health behaviours and use of preventive care were more frequent in the intervention than in the control group (based on z-statistics from generalised estimating equation models). For example, 70% compared to 62% were physically active (odds ratio 1.43, 95% CI 1.16-1.77, p = 0.001), and 66% compared to 59% had influenza vaccinations in the past year (odds ratio 1.35, 95% CI 1.09-1.66, p = 0.005). At 8 y, based on an intention-to-treat analysis, the estimated proportion alive was 77.9% in the intervention and 72.8% in the control group, for an absolute mortality difference of 4.9% (95% CI 1.3%-8.5%, p = 0.009; based on z-test for risk difference). The hazard ratio of death comparing intervention with control was 0.79 (95% CI 0.66-0.94, p = 0.009; based on Wald test from Cox regression model), and the number needed to receive the intervention to prevent one death was 21 (95% CI 12-79). The main limitations of the study include the single-site study design, the use of a brief self-administered questionnaire for 2-y outcome data collection, the unavailability of other long-term outcome data (e.g., functional status, nursing home admissions), and the availability of long-term follow-up data on mortality for analysis only in 2014. CONCLUSIONS This is the first trial to our knowledge demonstrating that a collaborative care model of HRA in community-dwelling older people not only results in better health behaviours and increased use of recommended preventive care interventions, but also improves survival. The intervention tested in our study may serve as a model of how to implement a relatively low-cost but effective programme of disease prevention and health promotion in older individuals. TRIAL REGISTRATION International Standard Randomized Controlled Trial Number: ISRCTN 28458424.

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OBJECTIVES The aim of this study was to optimise dexmedetomidine and alfaxalone dosing, for intramuscular administration with butorphanol, to perform minor surgeries in cats. METHODS Initially, cats were assigned to one of five groups, each composed of six animals and receiving, in addition to 0.3 mg/kg butorphanol intramuscularly, one of the following: (A) 0.005 mg/kg dexmedetomidine, 2 mg/kg alfaxalone; (B) 0.008 mg/kg dexmedetomidine, 1.5 mg/kg alfaxalone; (C) 0.012 mg/kg dexmedetomidine, 1 mg/kg alfaxalone; (D) 0.005 mg/kg dexmedetomidine, 1 mg/kg alfaxalone; and (E) 0.012 mg/kg dexmedetomidine, 2 mg/kg alfaxalone. Thereafter, a modified 'direct search' method, conducted in a stepwise manner, was used to optimise drug dosing. The quality of anaesthesia was evaluated on the basis of composite scores (one for anaesthesia and one for recovery), visual analogue scales and the propofol requirement to suppress spontaneous movements. The medians or means of these variables were used to rank the treatments; 'unsatisfactory' and 'promising' combinations were identified to calculate, through the equation first described by Berenbaum in 1990, new dexmedetomidine and alfaxalone doses to be tested in the next step. At each step, five combinations (one new plus the best previous four) were tested. RESULTS None of the tested combinations resulted in adverse effects. Four steps and 120 animals were necessary to identify the optimal drug combination (0.014 mg/kg dexmedetomidine, 2.5 mg/kg alfaxalone and 0.3 mg/kg butorphanol). CONCLUSIONS AND RELEVANCE The investigated drug mixture, at the doses found with the optimisation method, is suitable for cats undergoing minor clinical procedures.

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The nail unit is the largest and a rather complex skin appendage. It is located on the dorsal aspect of the tips of fingers and toes and has important protective and sensory functions. Development begins in utero between weeks 7 and 8 and is fully formed at birth. For its correct development, a great number of signals are necessary. Anatomically, it consists of 4 epithelial components: the matrix that forms the nail plate; the nail bed that firmly attaches the plate to the distal phalanx; the hyponychium that forms a natural barrier at the physiological point of separation of the nail from the bed; and the eponychium that represents the undersurface of the proximal nail fold which is responsible for the formation of the cuticle. The connective tissue components of the matrix and nail bed dermis are located between the corresponding epithelia and the bone of the distal phalanx. Characteristics of the connective tissue include: a morphogenetic potency for the regeneration of their epithelia; the lateral and proximal nail folds form a distally open frame for the growing nail; and the tip of the digit has rich sensible and sensory innervation. The blood supply is provided by the paired volar and dorsal digital arteries. Veins and lymphatic vessels are less well defined. The microscopic anatomy varies from nail subregion to subregion. Several different biopsy techniques are available for the histopathological evaluation of nail alterations.

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Diffusion-weighted imaging (DWI) is an established diagnostic tool with regards to the central nervous system (CNS) and research into its application in the musculoskeletal system has been growing. It has been shown that DWI has utility in differentiating vertebral compression fractures from malignant ones, assessing partial and complete tears of the anterior cruciate ligament (ACL), monitoring tumor response to therapy, and characterization of soft-tissue and bone tumors. DWI is however less useful in differentiating malignant vs. infectious processes. As of yet, no definitive qualitative or quantitative properties have been established due to reasons ranging from variability in acquisition protocols to overlapping imaging characteristics. Even with these limitations, DWI can still provide clinically useful information, increasing diagnostic accuracy and improving patient management when magnetic resonance imaging (MRI) findings are inconclusive. The purpose of this article is to summarize recent research into DWI applications in the musculoskeletal system.

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Paper presented at the French Colonial Historical Society annual Conference, Binghampton, University, NY on May 8, 2015

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In this work we will present a model that describes how the number of healthy and unhealthy subjects that belong to a cohort, changes through time when there are occurrences of health promotion campaigns aiming to change the undesirable behavior. This model also includes immigration and emigration components for each group and a component taking into account when a subject that used to perform a healthy behavior changes to perform the unhealthy behavior. We will express the model in terms of a bivariate probability generating function and in addition we will simulate the model. ^ An illustrative example on how to apply the model to the promotion of condom use among adolescents will be created and we will use it to compare the results obtained from the simulations and the results obtained by the probability generating function. ^

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Although many clinical trials investigated the use of IL-2, IL-12, and LAK in adoptive immunotherapy to treat cancer, only limited clinical success has been achieved. Better understanding of the intracellular processes that IL-2 and IL-12 utilize to generate LAK and other functions in NK cells is necessary to improve this mode of therapy. IL-2 and IL-12 stimulate extracellular signal-regulated protein kinase (ERK) and p38 MAPK in mitogen-activated T lymphocytes. The functional roles that these kinases play are still unclear. In this study, we examined whether MAPK Kinase (MKK)/ERK and/or p38 MAPK pathways are necessary for IL-2 or IL-12 to activate NK cells. We established that IL-2 activates MKK1/2/ERK pathway in freshly isolated human NK cells without any prior stimulation. Furthermore, we determined that an intact MKK/ERK pathway is necessary for IL-2 to activate NK cells to express at least four known biological responses: LAK activity, IFN-γ secretion, and CD25 and CD69 expression. Treatment of NK cells with a specific inhibitor of MKK1/2 PD98059, during the IL-2 stimulation blocked in a dose-dependent manner each of four activation parameters. Although activation of ERK was not detected in NK cells immediately after IL-12 stimulation, IL-12-induced functional activation was inhibited by the MKK1/2 inhibitor, as well. In contrast to what was observed by others in T lymphocytes, activation of p38 MAPK by IL-2 was not detected in NK cells. Additionally, a specific inhibitor of p38 MAPK (SB203850) did not inhibit IL-2-activated NK functions. These data reveal selective signaling differences between NK cells and T lymphocytes. Collectively, the data support that the MKK/ERK pathway plays a critical positive regulatory role in NK cells during activation by IL-2 and IL-12. ^

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9-β-D-arabinosylguanine (ara-G), an analogue of deoxyguanosine, has demonstrated T-lymphoblast selective anti-leukemia activity both in vitro and in vivo in cell lines and primary cells and in phase I investigations. The present work was initiated to identify factors that result in this selectivity. ^ The cytotoxicity of ara-G is manifest only after its phosphorylation. Experiments using cell lines transfected to overexpress specific nucleoside kinases demonstrated that the phosphorylation of ara-G to its monophosphate is by both cytoplasmic deoxycytidine kinase and mitochondria) deoxyguanosine kinase. Ara-G monophosphate is converted to its 5′-triphosphate (ara-GTP) in cells by these kinases and then incorporated into DNA. Mechanistic studies demonstrated that incorporation of ara-GTP into DNA was a necessary event for the induction of cell death. ^ Pharmacokinetic and pharmacodynamic studies utilizing three human acute leukemia cell lines, CEM (T-lymphoblastic), Raji (B-lymphoblastic), and ML-1 (myeloid) were performed. CEM cells were most sensitive to ara-G-induced inhibition of colony formation, accumulated ara-GTP at a faster rate and to a greater degree than either Raji or ML-1, but incorporated the lowest number of ara-G molecules into DNA. The position of incorporation was internal and similar in all cell lines. The terminal elimination phase of ara-GTP was >24 h and similar in these cells. Comparisons between inhibition of colony formation and ara-GTP incorporation into DNA demonstrated that while within a cell line there was correlation among these parameters, between cell lines there was no relationship between number of incorporated ara-G molecules and ara-G(TP)-mediated toxicity suggesting that there were additional factors. ^ The expression of membrane bound Fas and Fast was unchanged in all cell lines. In contrast, there was a 2-fold increase in soluble Fast, which was found exclusively in CEM cells. Ara-G-mediated apoptosis in CEM occurred from all phases of the cell cycle and was abrogated partially by Fas antagonist antibodies. These data suggest that Fas-mediated cell death due to the liberation of sFasL may be responsible for the hypersensitivity to ara-G manifested by immature T-cells such as CEM. The role of Fas in ara-G induced death of acute T-lymphoblastic leukemia cells during therapy needs to be tested. ^

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Neural tube defects (NTDs) are the most common severely disabling birth defects in the United States, with a frequency of approximately 1–2 of every 1,000 births. This text includes the identification and evaluation of candidate susceptibility genes that confer risk for the development of neural tube defects (NTDs). The project focused on isolated meningomyelocele, also termed spina bifida (SB). ^ Spina bifida is a complex disease with multifactorial inheritance, therefore the subject population (consisting of North American Caucasians and Hispanics of Mexicali-American descent) was composed of 459 simplex SB families who were tested for genetic associations utilizing the transmission disequilibrium test (TDT), a nonparametric linkage technique. Three categories of candidate genes were studied, including (1) human equivalents of genes determined in mouse models to cause NTDs, (2) HOX and PAX genes, and (3) the MTHFR gene involved in the metabolic pathway of folate. ^ The C677T variant of the 5,10-methylenetetrahydrofolate reductase (MTHFR) gene was the first mutation in this gene to be implicated as a risk factor for NTDs. Our evaluation of the MTHFR gene provides evidence that maternal C677T homozygosity is a risk factor for upper level spina bifida defects in Hispanics [OR = 2.3, P = 0.02]. This observed risk factor is of great importance due to the high prevalence of this homozygous genotype in the Hispanic population. Additionally, maternal C677T/A1298C compound heterozygosity is a risk factor for upper level spina bifida defects in non-Hispanic whites [OR = 3.6, P = 0.03]. ^ For TDT analysis, our total population of 1128 subjects were genotyped for 54 markers from within and/or flanking the 20 candidate genes/gene regions of interest. Significant TDT findings were obtained for 3 of the 54 analyzed markers: d20s101 flanking the PAX1 gene (P = 0.019), d1s228 within the PAX7 gene (P = 0.011), and d2s110 within the PAX8 gene (P = 0.013). These results were followed-up by testing the genes directly for mutations utilizing single-strand conformational analysis (SSCA) and direct sequencing. Multiple variations were detected in each of these PAX genes; however, these variations were not passed from parent to child in phase with the positively transmitted alleles. Therefore, these variations do not contribute to the susceptibility of spina bifida, but rather are previously unreported single nucleotide polymorphisms. ^