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Objective: Essential tremor (ET), while defined by progressive motor symptoms, is increasingly associated with cognitive impairments (e.g. attention, memory, and executive functions). This study characterizes the cognitive profile of individuals with ET on the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS), a commonly-used neuropsychological screening measure. Method: Seventy-seven individuals (mean age: 70.6, 34% female) diagnosed with ET and being considered for surgical/procedural intervention were recruited from a Movement Disorders Clinic. All participants completed the RBANS, Grooved Pegboard Test (GPB), and Fahn, Tolosa, Marin Tremor Scale (FTMTS) in the clinical evaluation of their tremor. Results: One-sample t-tests found Immediate Memory, Language, Attention, and Total Scale Index scores to be significantly lower than the expected population mean (p < .05). List Learning, Semantic Fluency, Coding, and List Recall subtests were significantly lower and Picture Naming was significantly higher than the expected population mean (p < .05). GPB scores were correlated with the Attention Index as well as List Learning and Coding subtests. FTMTS Severity was correlated with the Coding subtest and FTMTS Disability was correlated with the Figure Recall subtest. Conclusions: Results support prior literature indicating cognitive weaknesses in those with ET. Individuals with ET had poorer global cognitive abilities, with specific decrements in Immediate Memory, Attention, and Language. Notably, the Attention Index and Coding subtest were most affected by motor functioning. Cognitive screening measures, like the RBANS, can efficiently identify strengths and weaknesses in individuals with ET seeking surgical/procedural interventions.
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Transtornos Cognitivos , Tremor Essencial , Humanos , Feminino , Idoso , Masculino , Transtornos Cognitivos/diagnóstico , Tremor Essencial/diagnóstico , Tremor Essencial/complicações , Tremor/complicações , Testes Neuropsicológicos , CogniçãoRESUMO
Introduction of new methods requires meticulous evaluation before they can be applied to forensic genetic case work. Here, a custom QIAseq Targeted DNA panel with 164 ancestry informative markers was assessed using the MiSeq sequencing platform. Concordance, sensitivity, and the capability for analysis of mixtures were tested. The assay gave reproducible and nearly concordant results with an input of 10 and 2 ng DNA. Lower DNA input led to an increase in both locus and allele drop-outs, and a higher variation in heterozygote balance. Locus or allele drop-outs in the samples with less than 2 ng DNA input were not necessarily associated with the overall performance of a locus. Thus, the QIAseq assay will be difficult to implement in a forensic genetic setting where the sample material is often scarce and of poor quality. With equal or near equal mixture ratios, the mixture DNA profiles were easily identified by an increased number of imbalanced heterozygotes. For more skewed mixture ratios, the mixture DNA profiles were identified by an increased noise level. Lastly, individuals from Great Britain and the Middle East were investigated. The Middle Eastern individuals showed a greater affinity with South European populations compared to North European populations.
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Impressões Digitais de DNA , Sequenciamento de Nucleotídeos em Larga Escala , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNA , Marcadores Genéticos , HumanosRESUMO
Individual age estimation can be applied to criminal, legal, and anthropological investigations. DNA methylation has been established as the biomarker of choice for age prediction, since it was observed that specific CpG positions in the genome show systematic changes during an individual's lifetime, with progressive increases or decreases in methylation levels. Subsequently, several forensic age prediction models have been reported, providing average age prediction error ranges of ±3-4 years, using a broad spectrum of technologies and underlying statistical analyses. DNA methylation assessment is not categorical but quantitative. Therefore, the detection platform used plays a pivotal role, since quantitative and semi-quantitative technologies could potentially result in differences in detected DNA methylation levels. In the present study, we analyzed as a shared sample pool, 84 blood-based DNA controls ranging from 18 to 99 years old using four different technologies: EpiTYPER®, pyrosequencing, MiSeq, and SNaPshotTM. The DNA methylation levels detected for CpG sites from ELOVL2, FHL2, and MIR29B2 with each system were compared. A restricted three CpG-site age prediction model was rebuilt for each system, as well as for a combination of technologies, based on previous training datasets, and age predictions were calculated accordingly for all the samples detected with the previous technologies. While the DNA methylation patterns and subsequent age predictions from EpiTYPER®, pyrosequencing, and MiSeq systems are largely comparable for the CpG sites studied, SNaPshotTM gives bigger differences reflected in higher predictive errors. However, these differences can be reduced by applying a z-score data transformation.
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BACKGROUND: Multiple modern Indian hospitals operate at very low cost while meeting US-equivalent quality accreditation standards. Though US hospitals face intensifying pressure to lower their cost, including proposals to extend Medicare payment rates to all admissions, the transferability of Indian hospitals' cost advantages to US peers remains unclear. METHODS: Using time-driven activity-based costing methods, we estimate the average cost of personnel and space for an elective coronary artery bypass graft (CABG) surgery at two American hospitals and one Indian hospital (NH). All three hospitals are Joint Commission accredited and have reputations for use of modern performance management methods. Our case study applies several analytic steps to distinguish transferable from non-transferable sources of NH's cost savings. RESULTS: After removing non-transferable sources of efficiency, NH's residual cost advantage primarily rests on shifting tasks to less-credentialed and/or less-experienced personnel who are supervised by highly-skilled personnel when perceived risk of complications is low. NH's high annual CABG volume facilitates such supervised work "downshifting." The study is subject to limitations inherent in case studies, does not account for the younger age of NH's patients, or capture savings attributable to NH's negligible frequency of re-admission or post-acute care facility placement. CONCLUSIONS: Most transferable bases for a modern Indian hospital's cost advantage would require more flexible American states' hospital and health professional licensing regulations, greater family participation in inpatient care, and stronger support by hospital executives and clinicians for substantially lowering the cost of care via regionalization of complex surgeries and weekend use of costly operating rooms.
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Ponte de Artéria Coronária/economia , Doença da Artéria Coronariana/cirurgia , Procedimentos Cirúrgicos Eletivos/economia , Custos Hospitalares , Medicare/economia , Transferência de Pacientes/economia , Doença da Artéria Coronariana/economia , Feminino , Humanos , Índia , Masculino , Estados UnidosRESUMO
In a previous EUROFORGEN/EDNAP collaborative exercise, we tested two assays for targeted mRNA massively parallel sequencing for the identification of body fluids/tissues, optimized for the Illumina MiSeq/FGx and the Ion Torrent PGM/S5 platforms, respectively. The task of the second EUROFORGEN/EDNAP collaborative exercise was to analyze dried body fluid stains with two different multiplexes, the former Illumina 33plex mRNA panel for body fluid/tissue identification and a 35plex cSNP panel for assignment of body fluids/tissues to donors that was introduced in a proof-of-concept study recently. The coding region SNPs (cSNPs) are located within the body fluid specific mRNA transcripts and represent a direct link between the body fluid and the donor. We predicted the origin of the stains using a partial least squares discriminant analysis (PLS-DA) model, where most of the single source samples were correctly predicted. The mixed body fluid stains showed poorer results, however, at least one component was predicted correctly in most stains. The cSNP data demonstrated that coding region SNPs can give valuable information on linking body fluids/tissues with donors in mixed body fluid stains. However, due to the unfavorable performance of some cSNPs, the interpretation remains challenging. As a consequence, additional markers are needed to increase the discrimination power in each body fluid/tissue category.
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Genética Forense/métodos , Sequenciamento de Nucleotídeos em Larga Escala , RNA Mensageiro/genética , Sangue , Muco do Colo Uterino , Feminino , Marcadores Genéticos , Humanos , Masculino , Menstruação , Polimorfismo de Nucleotídeo Único , Saliva , Sêmen , Pele/químicaRESUMO
Inference of biogeographic origin is an important factor in clinical, population and forensic genetics. The information provided by AIMs (Ancestry Informative Markers) can allow the differentiation of major continental population groups, and several AIM panels have been developed for this purpose. However, from these major population groups, Eurasia covers a wide area between two continents that is difficult to differentiate genetically. These populations display a gradual genetic cline from West Europe to South Asia in terms of allele frequency distribution. Although differences have been reported between Europe and South Asia, Middle East populations continue to be a target of further investigations due to the lack of genetic variability, therefore hampering their genetic differentiation from neighboring populations. In the present study, a custom-built ancestry panel was developed to analyze North African and Middle Eastern populations, designated the 'NAME' panel. The NAME panel contains 111 SNPs that have patterns of allele frequency differentiation that can distinguish individuals originating in North Africa and the Middle East when combined with a previous set of 126 Global AIM-SNPs.
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População Negra/genética , Genética Forense/métodos , Genética Populacional , África do Norte , Impressões Digitais de DNA , Frequência do Gene , Marcadores Genéticos , Técnicas de Genotipagem , Humanos , Oriente Médio , Reação em Cadeia da Polimerase , Polimorfismo de Nucleotídeo Único , Análise de Componente PrincipalRESUMO
The STR sequence template file published in 2016 as part of the considerations from the DNA Commission of the International Society for Forensic Genetics on minimal STR sequence nomenclature requirements, has been comprehensively revised and audited using the latest GRCh38 genome assembly. The list of forensic STRs characterized was expanded by including supplementary autosomal, X- and Y-chromosome microsatellites in less common use for routine DNA profiling, but some likely to be adopted in future massively parallel sequencing (MPS) STR panels. We outline several aspects of sequence alignment and annotation that required care and attention to detail when comparing sequences to GRCh37 and GRCh38 assemblies, as well as the necessary matching of MPS-based allele descriptions to previously established repeat region structures described in initial sequencing studies of the less well known forensic STRs. The revised sequence guide is now available in a dynamically updated FTP format from the STRidER website with a date-stamped change log to allow users to explore their own MPS data with the most up-to-date forensic STR sequence information compiled in a simple guide.
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Impressões Digitais de DNA , Repetições de Microssatélites , Software , Genética Forense/normas , Sequenciamento de Nucleotídeos em Larga Escala , HumanosRESUMO
Gizzard helminths were examined in 100 (50 adult, 50 juvenile) female northern pintails ( Anas acuta). Sixty-three individual helminths, representing 5 species ( Amidostomum acutum, Echinuria uncinata, Epomidiostomum uncinatum, Streptocara crassicauda, and Gastrotaenia cygni) were found. Twenty-seven northern pintails were infected with 1-3 helminth species and averaged 1.4 species. Overall, A. acutum and G. cygni were the most prevalent and abundant species (20%, n = 31 and 10%, n = 25, respectively), followed by S. crassicauda (5%, n = 5), E. uncinata (1%, n = 1), and E. uncinatum (1%, n = 1). Intensity of infection for A. acutum, E. uncinata, E. uncinatum, S. crassicauda, and G. cygni was 1.6 ± 0.3 [SE], 1.0 ± 0, 1.0 ± 0, 1.0 ± 0, and 2.5 ± 0.6, respectively. Our findings represent new information about gizzard helminth infections in northern pintails wintering along the Texas coast.
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Doenças das Aves/parasitologia , Patos/parasitologia , Moela das Aves/parasitologia , Helmintíase Animal/parasitologia , Migração Animal , Animais , Doenças das Aves/epidemiologia , Cestoides/isolamento & purificação , Feminino , Helmintíase Animal/epidemiologia , Estações do Ano , Spirurina/isolamento & purificação , Texas/epidemiologia , Trichostrongyloidea/isolamento & purificaçãoRESUMO
PURPOSE: To evaluate the effect of catheter connections on drainage catheters' flow rate. MATERIALS AND METHOD: The in vitro model used commercially available catheters (8.5-F, 10.2-F, 12-F, and 14-F), connections - Luer-lok (2.33mm inner diameter), and stopcocks (1.33mm, 2.00mm, and 2.67mm inner diameters), water, ultrasound gel, textured vegetable protein (TVP) 2-mm particles, and collection bags. Plain water, viscous fluid (30% ultrasound gel solution in water), or water/viscous fluid with TVP were placed in collection bags and drained by gravity through each of the catheters and each connection. The flow rate was measured, recorded, and compared for each catheter and each connection as well as to the control flow rate of the catheters without connections. Ten one-minute trials were performed, and the mean flow rates were analyzed using Student t-test and Pearson correlation coefficient. RESULTS: Flow rate was significantly decreased in the 12-F and 14-F catheters with all stopcock and Luer-Lok connections with both water and viscous fluids. There was no significant reduction in flow for the 8.5-F and 10.2-F catheters with the 2.00-mm, 2.33-mm, and 2.67-mm connections; flow rate was significantly decreased in the 8.5-F and 10.2-F catheters with the 1.33-mm connection. A majority of trials with particulate fluid became occluded, and no consistent pattern between connections could be made. CONCLUSION: This in vitro study suggests that stopcock and Luer-Lok connections limit catheter flow rate when their inner diameter is less than that of the drainage catheter.
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Catéteres , Drenagem/instrumentação , Reologia , Desenho de Equipamento , Humanos , Teste de MateriaisAssuntos
Bile , Cateterismo , Catéteres , Drenagem , Hidrodinâmica , Desenho de Equipamento , Modelos AnatômicosRESUMO
A collaborative European DNA Profiling (EDNAP) Group exercise was undertaken to assess the performance of an earlier described SNaPshot™-based screening assay (denoted mini-mtSNaPshot) (Weiler et al., 2016) [1] that targets 18 single nucleotide polymorphism (SNP) positions in the mitochondrial (mt) DNA control region and allows for discrimination of major European mtDNA haplogroups. Besides the organising laboratory, 14 forensic genetics laboratories were involved in the analysis of 13 samples, which were centrally prepared and thoroughly tested prior to shipment. The samples had a variable complexity and comprised straightforward single-source samples, samples with dropout or altered peak sizing, a point heteroplasmy and two-component mixtures resulting in one to five bi-allelic calls. The overall success rate in obtaining useful results was high (97.6%) given that some of the participating laboratories had no previous experience with the typing technology and/or mtDNA analysis. The majority of the participants proceeded to haplotype inference to assess the feasibility of assigning a haplogroup and checking phylogenetic consistency when only 18 SNPs are typed. To mimic casework procedures, the participants compared the SNP typing data of all 13 samples to a set of eight mtDNA reference profiles that were described according to standard nomenclature (Parson et al., 2014) [2], and indicated whether these references matched each sample or not. Incorrect scorings were obtained for 2% of the comparisons and derived from a subset of the participants, indicating a need for training and guidelines regarding mini-mtSNaPshot data interpretation.
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Impressões Digitais de DNA/normas , DNA Mitocondrial/genética , Polimorfismo de Nucleotídeo Único , Genética Forense/normas , Haplótipos , Humanos , Laboratórios/normasRESUMO
The EUROFORGEN Global ancestry-informative SNP (AIM-SNPs) panel is a forensic multiplex of 128 markers designed to differentiate an individual's ancestry from amongst the five continental population groups of Africa, Europe, East Asia, Native America, and Oceania. A custom multiplex of AmpliSeq™ PCR primers was designed for the Global AIM-SNPs to perform massively parallel sequencing using the Ion PGM™ system. This study assessed individual SNP genotyping precision using the Ion PGM™, the forensic sensitivity of the multiplex using dilution series, degraded DNA plus simple mixtures, and the ancestry differentiation power of the final panel design, which required substitution of three original ancestry-informative SNPs with alternatives. Fourteen populations that had not been previously analyzed were genotyped using the custom multiplex and these studies allowed assessment of genotyping performance by comparison of data across five laboratories. Results indicate a low level of genotyping error can still occur from sequence misalignment caused by homopolymeric tracts close to the target SNP, despite careful scrutiny of candidate SNPs at the design stage. Such sequence misalignment required the exclusion of component SNP rs2080161 from the Global AIM-SNPs panel. However, the overall genotyping precision and sensitivity of this custom multiplex indicates the Ion PGM™ assay for the Global AIM-SNPs is highly suitable for forensic ancestry analysis with massively parallel sequencing.
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Genética Populacional , Sequenciamento de Nucleotídeos em Larga Escala/instrumentação , Polimorfismo de Nucleotídeo Único , Grupos Raciais/genética , Degradação Necrótica do DNA , Impressões Digitais de DNA , Primers do DNA , Bases de Dados Genéticas , Frequência do Gene , Marcadores Genéticos , Genótipo , Humanos , Reação em Cadeia da PolimeraseRESUMO
PURPOSE: The primary goal of this study was to demonstrate the value of micro-CT imaging in a rheumatoid arthritis (RA) mouse model. The secondary goal was to assess whether manual correction of the articular surface regions of interest (ROI) identification of the semi-automated methods may result in more effective assessment of bone volume and density loss. MATERIALS AND METHODS: Collagen-induced arthritis (CIA) was induced in six DBA/1J mice at 12 weeks of age and three other DBA/1J identical mice served as controls. Micro-CT images were acquired at baseline and at four, seven, and nine weeks post-induction. Disease was monitored via ROI analysis, and ROIs were first generated using semi-automated techniques. These ROIs were manually manipulated so that a variety of edge irregularities were corrected. Effort was focused on the proximal and distal humerus and the distal femur. ROI volume and density were calculated, and data were compared. A histologic analysis of the study mice was also performed after the last time frame. RESULTS: There was a significant difference between the volume data comparison between the manually manipulated data and the semi-automated routine data across all time frames and across both humeri and femurs. There was no significant difference in densities calculated in Hounsfield units across any of the time frames, humeri or femurs, except for one time frame. CONCLUSION: Our findings suggest that the manual correction technique of semi-automated data can be used to quantify and evaluate bone volume, density, and joint surface architecture changes in a RA mouse model.
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Artrite Reumatoide/diagnóstico por imagem , Progressão da Doença , Fêmur/diagnóstico por imagem , Úmero/diagnóstico por imagem , Microtomografia por Raio-X , Animais , Densidade Óssea , Modelos Animais de Doenças , Camundongos Endogâmicos DBARESUMO
BACKGROUND: Overuse of cranial computed tomography scans in children with blunt head trauma unnecessarily exposes them to radiation. The Pediatric Emergency Care Applied Research Network (PECARN) blunt head trauma prediction rules identify children who do not require a computed tomography scan. Electronic health record (EHR) based clinical decision support (CDS) may effectively implement these rules but must only be provided for appropriate patients in order to minimize excessive alerts. OBJECTIVES: To develop, implement and evaluate site-specific groupings of chief complaints (CC) that accurately identify children with head trauma, in order to activate data collection in an EHR. METHODS: As part of a 13 site clinical trial comparing cranial computed tomography use before and after implementation of CDS, four PECARN sites centrally developed and locally implemented CC groupings to trigger a clinical trial alert (CTA) to facilitate the completion of an emergency department head trauma data collection template. We tested and chose CC groupings to attain high sensitivity while maintaining at least moderate specificity. RESULTS: Due to variability in CCs available, identical groupings across sites were not possible. We noted substantial variability in the sensitivity and specificity of seemingly similar CC groupings between sites. The implemented CC groupings had sensitivities greater than 90% with specificities between 75-89%. During the trial, formal testing and provider feedback led to tailoring of the CC groupings at some sites. CONCLUSIONS: CC groupings can be successfully developed and implemented across multiple sites to accurately identify patients who should have a CTA triggered to facilitate EHR data collection. However, CC groupings will necessarily vary in order to attain high sensitivity and moderate-to-high specificity. In future trials, the balance between sensitivity and specificity should be considered based on the nature of the clinical condition, including prevalence and morbidity, in addition to the goals of the intervention being considered.
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Traumatismos Craniocerebrais/diagnóstico por imagem , Sistemas de Apoio a Decisões Clínicas , Registros Eletrônicos de Saúde , Uso Excessivo dos Serviços de Saúde/prevenção & controle , Criança , Traumatismos Craniocerebrais/enfermagem , Humanos , Sistemas de Registro de Ordens Médicas/estatística & dados numéricos , RadiografiaRESUMO
There is increasing interest in forensic ancestry tests, which are part of a growing number of DNA analyses that can enhance routine profiling by obtaining additional genetic information about unidentified DNA donors. Nearly all ancestry tests use single nucleotide polymorphisms (SNPs), but these currently rely on SNaPshot single base extension chemistry that can fail to detect mixed DNA. Insertion-deletion polymorphism (Indel) tests have been developed using dye-labeled primers that allow direct capillary electrophoresis detection of PCR products (PCR-to-CE). PCR-to-CE maintains the direct relationship between input DNA and signal strength as each marker is detected with a single dye, so mixed DNA is more reliably detected. We report the results of a collaborative inter-laboratory exercise of 19 participants (15 from the EDNAP European DNA Profiling group) that assessed a 34-plex SNP test using SNaPshot and a 46-plex Indel test using PCR-to-CE. Laboratories were asked to type five samples with different ancestries and detect an additional mixed DNA sample. Statistical inference of ancestry was made by participants using the Snipper online Bayes analysis portal plus an optional PCA module that analyzes the genotype data alongside calculation of Bayes likelihood ratios. Exercise results indicated consistent genotyping performance from both tests, reaching a particularly high level of reliability for the Indel test. SNP genotyping gave 93.5% concordance (compared to the organizing laboratory's data) that rose to 97.3% excluding one laboratory with a large number of miscalled genotypes. Indel genotyping gave a higher concordance rate of 99.8% and a reduced no-call rate compared to SNP analysis. All participants detected the mixture from their Indel peak height data and successfully assigned the correct ancestry to the other samples using Snipper, with the exception of one laboratory with SNP miscalls that incorrectly assigned ancestry of two samples and did not obtain informative likelihood ratios for a third. Therefore, successful ancestry assignments were achieved by participants in 92 of 95 Snipper analyses. This exercise demonstrates that ancestry inference tests based on binary marker sets can be readily adopted by laboratories that already have well-established CE regimes in place. The Indel test proved to be easy to use and allowed all exercise participants to detect the DNA mixture as well as achieving complete and concordant profiles in nearly all cases. Lastly, two participants successfully ran parallel next-generation sequencing analyses (each using different systems) and achieved high levels of genotyping concordance using the exercise PCR primer mixes unmodified.
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Eletroforese Capilar/métodos , Genética Forense , Marcadores Genéticos , DNA/genética , Genótipo , Humanos , Polimorfismo de Nucleotídeo ÚnicoRESUMO
PURPOSE: To report the sequential placement of inferior vena cava filter (IVCF) and peripherally inserted central catheter (PICC) using the same upper extremity venous access. MATERIAL AND METHODS: This is a retrospective study that reviewed the medical records of 379 consecutive patients who underwent IVCF insertion during a 39-month period at our center. Of these 379 patients, 28 patients had sequential insertion of an IVCF and a PICC through the same upper extremity venous access. The same vein entry site was used for placement of the IVCF followed by PICC insertion. Data collected included: indication and duration of IVCF and PICC placement, access site location, complications, and the type of IVCF. RESULTS: IVCFs were placed for prophylactic purposes in 15 patients (53.6%) and therapeutic purposes in 13 patients (46.4%). Right upper extremity veins were used for venous access in 27 patients (96.4%): brachial (n=16), basilic (n=9), and cephalic (n=2). The left basilic vein was used in one patient (3.6%). IVCFs were temporary in 20 patients (71.4%) and permanent in 8 patients (28.6%). There were no procedural complications. The OptEase filter was used in 23 patients (82.1%) and the TrapEase filter was used in 5 patients (17.9%). CONCLUSION: Simultaneous IVCF and PICC insertion using the same upper extremity venous access was feasible and safe in our series. This combined technique provides the patient with central venous access for repeated blood collections and intravenous therapy.
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Cateterismo Periférico , Cateteres Venosos Centrais , Filtros de Veia Cava , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Braço , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Implantação de Prótese/métodos , Estudos Retrospectivos , Extremidade Superior , Veias , Adulto JovemRESUMO
AIM: To evaluate the influence of number and location of catheter shaft side holes regarding drainage efficiency in an in vitro model. MATERIALS AND METHODS: Three different drainage catheter models were constructed: open-ended model with no side holes (one catheter), unilateral side hole model (six catheters with one to six unilateral side holes), and bilateral side hole model (six catheters with one to six bilateral side holes). Catheters were inserted into a drainage output-measuring device with a constant-pressure reservoir of water. The volume of water evacuated by each of the catheters at 10-second intervals was measured. A total of five trials were performed for each catheter. Data were analysed using one-way analysis of variance. RESULTS: The open-ended catheter had a mean drainage volume comparable to the unilateral model catheters with three, four, and five side holes. Unilateral model catheters had significant drainage volume increases up to three side holes; unilateral model catheters with more than three side holes had no significant improvement in drainage volume. All bilateral model catheters had significantly higher mean drainage volumes than their unilateral counterparts. There was no significant difference between the mean drainage volume with one, two, or three pairs of bilateral side holes. Further, there was no drainage improvement by adding additional bilateral side holes. CONCLUSION: The present in vitro study suggests that beyond a critical side hole number threshold, adding more distal side holes does not improve catheter drainage efficiency. These results may be used to enhance catheter design towards improving their drainage efficiency.
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Catéteres , Drenagem/instrumentação , Desenho de Equipamento , Humanos , Técnicas In Vitro , PolietilenoRESUMO
Next generation sequencing (NGS) offers the opportunity to analyse forensic DNA samples and obtain massively parallel coverage of targeted short sequences with the variants they carry. We evaluated the levels of sequence coverage, genotyping precision, sensitivity and mixed DNA patterns of a prototype version of the first commercial forensic NGS kit: the HID-Ion AmpliSeq™ Identity Panel with 169-markers designed for the Ion PGM™ system. Evaluations were made between three laboratories following closely matched Ion PGM™ protocols and a simple validation framework of shared DNA controls. The sequence coverage obtained was extensive for the bulk of SNPs targeted by the HID-Ion AmpliSeq™ Identity Panel. Sensitivity studies showed 90-95% of SNP genotypes could be obtained from 25 to 100pg of input DNA. Genotyping concordance tests included Coriell cell-line control DNA analyses checked against whole-genome sequencing data from 1000 Genomes and Complete Genomics, indicating a very high concordance rate of 99.8%. Discordant genotypes detected in rs1979255, rs1004357, rs938283, rs2032597 and rs2399332 indicate these loci should be excluded from the panel. Therefore, the HID-Ion AmpliSeq™ Identity Panel and Ion PGM™ system provide a sensitive and accurate forensic SNP genotyping assay. However, low-level DNA produced much more varied sequence coverage and in forensic use the Ion PGM™ system will require careful calibration of the total samples loaded per chip to preserve the genotyping reliability seen in routine forensic DNA. Furthermore, assessments of mixed DNA indicate the user's control of sequence analysis parameter settings is necessary to ensure mixtures are detected robustly. Given the sensitivity of Ion PGM™, this aspect of forensic genotyping requires further optimisation before massively parallel sequencing is applied to routine casework.
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Genética Forense/métodos , Técnicas de Genotipagem/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Polimorfismo de Nucleotídeo Único , DNA/análise , DNA/genética , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , Análise de Sequência de DNARESUMO
Upon re-testing of a DNA extract as part of a defence examination, a discordant result was observed at D16S539. Further STR testing and DNA sequencing of the sample identified the cause as a primer binding site mutation which was shown to be a previously unreported SNP. The testing results obtained in this case are considered in light of the current ongoing Multiplex Upgrade Project in the UK and the likely increase in discordant results that may be observed once different next generation kits are introduced.