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1.
J Med Libr Assoc ; 108(4): 534-546, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33013210

RESUMO

OBJECTIVE: The authors reviewed educational interventions for improving literature searching skills in the health sciences. METHODS: We performed a scoping review of experimental and quasi-experimental studies published in English and German, irrespective of publication year. Targeted outcomes were objectively measurable literature searching skills (e.g., quality of search strategy, study retrieval, precision). The search methods consisted of searching databases (CINAHL, Embase, MEDLINE, PsycINFO, Web of Science), tracking citations, free web searching, and contacting experts. Two reviewers performed screening and data extraction. To evaluate the completeness of reporting, the Template for Intervention Description and Replication (TIDieR) was applied. RESULTS: We included 6 controlled trials and 8 pre-post trials from the 8,484 references that we screened. Study participants were students in various health professions and physicians. The educational formats of the interventions varied. Outcomes clustered into 2 categories: (1) developing search strategies (e.g., identifying search concepts, selecting databases, applying Boolean operators) and (2) database searching skills (e.g., searching PubMed, MEDLINE, or CINAHL). In addition to baseline and post-intervention measurement, 5 studies reported follow-up. Almost all studies adequately described their intervention procedures and delivery but did not provide access to the educational material. The expertise of the intervention facilitators was described in only 3 studies. CONCLUSIONS: The results showed a wide range of study populations, interventions, and outcomes. Studies often lacked information about educational material and facilitators' expertise. Further research should focus on intervention effectiveness using controlled study designs and long-term follow-up. To ensure transparency, replication, and comparability, studies should rigorously describe their intervention.


Assuntos
Educação Médica/métodos , Armazenamento e Recuperação da Informação/métodos , Publicações Periódicas como Assunto , Estudantes de Medicina , Humanos
2.
J Surg Oncol ; 119(6): 728-736, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30674074

RESUMO

BACKGROUND AND OBJECTIVES: Postoperative lymphoceles and further wound complications occur frequently after radical inguinal lymph node dissection (ILND). In various studies, tissue sealants have shown to reduce the incidence of postoperative morbidity. METHODS: A systematic review and meta-analysis of randomized controlled trials (RCTs) investigating the effectiveness of tissue sealants in reducing the incidence of postoperative lymphoceles following ILND in patients with melanoma was conducted. Individual patient data was requested to pool the data for meta-analysis appropriately. RESULTS: Thousand seven hundred twenty-nine manuscripts were screened for eligibility. Six RCTs published between 1986 and 2012 were identified including 194 patients for ILND. Only four RCTs were included in the meta-analysis. No study properly defined the term "lymphocele." Tissue sealants failed to influence the duration of drain placement (mean difference [MD] = -3.05 days; z = 1.18; P = 0.24), total drainage volume (MD = 598.39 mL; z = 1.49; P = 0.14), the incidence of postoperative seroma, wound infection and skin necrosis. CONCLUSIONS: No improvement was identified with the use of tissue sealants, however, a valid comparison of the results of included trials was difficult owing to the lack of a definition of the term "lymphocele." Other surgical techniques and trials using validated endpoint definitions are required to reevaluate these findings.


Assuntos
Excisão de Linfonodo , Linfocele/prevenção & controle , Complicações Pós-Operatórias/prevenção & controle , Adesivos Teciduais/uso terapêutico , Drenagem , Virilha , Humanos , Metástase Linfática , Linfocele/etiologia , Melanoma/patologia , Melanoma/cirurgia , Neoplasias Cutâneas/patologia
3.
Sensors (Basel) ; 16(10)2016 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-27669241

RESUMO

The use of massive multiple-input multiple-output (MIMO) techniques for communication at millimeter-Wave (mmW) frequency bands has become a key enabler to meet the data rate demands of the upcoming fifth generation (5G) cellular systems. In particular, analog and hybrid beamforming solutions are receiving increasing attention as less expensive and more power efficient alternatives to fully digital precoding schemes. Despite their proven good performance in simple setups, their suitability for realistic cellular systems with many interfering base stations and users is still unclear. Furthermore, the performance of massive MIMO beamforming and precoding methods are in practice also affected by practical limitations and hardware constraints. In this sense, this paper assesses the performance of digital precoding and analog beamforming in an urban cellular system with an accurate mmW channel model under both ideal and realistic assumptions. The results show that analog beamforming can reach the performance of fully digital maximum ratio transmission under line of sight conditions and with a sufficient number of parallel radio-frequency (RF) chains, especially when the practical limitations of outdated channel information and per antenna power constraints are considered. This work also shows the impact of the phase shifter errors and combiner losses introduced by real phase shifter and combiner implementations over analog beamforming, where the former ones have minor impact on the performance, while the latter ones determine the optimum number of RF chains to be used in practice.

4.
Transfus Med Hemother ; 41(5): 364-74, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25538539

RESUMO

To be able to take well-informed decisions or carry out sound research, clinicians and researchers alike require specific information seeking skills matching their respective information needs. Biomedical information is traditionally available via different literature databases. This article gives an introduction to two diverging sources, PubMed (23 million references) and The Cochrane Library (800,000 references), both of which offer sophisticated instruments for searching an increasing amount of medical publications of varied quality and ambition. Whereas PubMed as an unfiltered source of primary literature comprises all different kinds of publication types occurring in academic journals, The Cochrane Library is a pre-filtered source which offers access to either synthesized publication types or critically appraised and carefully selected references. A search approach has to be carried out deliberately and requires a good knowledge on the scope and features of the databases as well as on the ability to build a search strategy in a structured way. We present a specific and a sensitive search approach, making use of both databases within two application case scenarios in order to identify the evidence on granulocyte transfusions for infections in adult patients with neutropenia.

5.
Front Immunol ; 15: 1403771, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38855104

RESUMO

Background: Immunotherapeutic approaches, including immune checkpoint inhibitor (ICI) therapy, are increasingly recognized for their potential. Despite notable successes, patient responses to these treatments vary significantly. The absence of reliable predictive and prognostic biomarkers hampers the ability to foresee outcomes. This meta-analysis aims to evaluate the predictive significance of circulating myeloid-derived suppressor cells (MDSC) in patients with solid tumors undergoing ICI therapy, focusing on progression-free survival (PFS) and overall survival (OS). Methods: A comprehensive literature search was performed across PubMed and EMBASE from January 2007 to November 2023, utilizing keywords related to MDSC and ICI. We extracted hazard ratios (HRs) and 95% confidence intervals (CIs) directly from the publications or calculated them based on the reported data. A hazard ratio greater than 1 indicated a beneficial effect of low MDSC levels. We assessed heterogeneity and effect size through subgroup analyses. Results: Our search yielded 4,023 articles, of which 17 studies involving 1,035 patients were included. The analysis revealed that patients with lower levels of circulating MDSC experienced significantly improved OS (HR=2.13 [95% CI 1.51-2.99]) and PFS (HR=1.87 [95% CI 1.29-2.72]) in response to ICI therapy. Notably, heterogeneity across these outcomes was primarily attributed to differences in polymorphonuclear MDSC (PMN-MDSC) subpopulations and varying cutoff methodologies used in the studies. The monocytic MDSC (M-MDSC) subpopulation emerged as a consistent and significant prognostic marker across various subgroup analyses, including ethnicity, tumor type, ICI target, sample size, and cutoff methodology. Conclusions: Our findings suggest that standardized assessment of MDSC, particularly M-MDSC, should be integral to ICI therapy strategies. These cells hold the promise of identifying patients at risk of poor response to ICI therapy, enabling tailored treatment approaches. Further research focusing on the standardization of markers and validation of cutoff methods is crucial for integrating MDSC into clinical practice. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42023420095, identifier CRD42023420095.


Assuntos
Biomarcadores Tumorais , Inibidores de Checkpoint Imunológico , Células Supressoras Mieloides , Neoplasias , Humanos , Células Supressoras Mieloides/imunologia , Neoplasias/tratamento farmacológico , Neoplasias/imunologia , Neoplasias/sangue , Inibidores de Checkpoint Imunológico/uso terapêutico , Biomarcadores Tumorais/sangue , Prognóstico
6.
Sports Med Open ; 9(1): 61, 2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37466877

RESUMO

BACKGROUND: Weak lower body strength and balance impairments are fundamental risk factors for mobility impairments and falls that can be improved by physical activity (PA). Previous meta-analyses have focused on these risk factors in adults aged ≥ 65 years. Yet, the potential of PA for improving these risk factors in middle-aged populations has not been systematically investigated. This systematic review and meta-analysis aim to examine the effect of general and structured PA on lower limb strength, postural balance and falls in middle-aged adults. METHODS: A computerized systematic literature search was conducted in the electronic databases MEDLINE, CINAHL, Web of Science and Cochrane Library. PA intervention types were classified according to the ProFaNE taxonomy. Randomized controlled trials exploring the effects of PA on strength (e.g., leg press one-repetition-maximum), balance (e.g., single limb stance) and falls (e.g., fall rates) in adults aged 40-60 years were systematically searched and included in a network analysis. Moderator analyses were performed for specific subgroups (age, sex, low PA). The methodological quality of the included studies was assessed using the Physiotherapy Evidence Database (PEDro) Scale. RESULTS: Out of 7170 articles screened, 66 studies (median PEDro score 5) with 3387 participants were included. Strong, significant effects on muscle strength were found for strength (SMD = 1.02), strength-aerobic (SMD = 1.41), strength-endurance (SMD = 0.92) and water-based (SMD = 1.08) training (52 studies, I2 = 79.3%). Strength training (SMD = 1.16), strength-aerobic (SMD = 0.98) and 3D training (SMD = 1.31) improved postural balance (30 studies, I2 = 88.1%). Moderator analyses revealed significant effects of specific intervention types on certain subgroups and subdomains of strength and balance. No studies were found measuring falls. CONCLUSIONS: Structured PA interventions in middle-aged adults improve strength and balance outcomes related to functional impairments and falls. Strength training increases both strength and balance and can be recommended to prevent age-related functional decline. However, the interpretability of the results is limited due to considerable heterogeneity and the overall low methodological quality of the included studies. Long-term trials are needed to determine the preventive potential of PA on strength, balance and falls. This meta-analysis may inform guidelines for tailored training during middle age to promote healthy aging. Prospero registration: CRD42020218643.

7.
Minerva Urol Nephrol ; 74(5): 538-550, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35274903

RESUMO

INTRODUCTION: Artificial intelligence (AI) has been successfully applied for automatic tumor detection and grading in histopathological image analysis in urologic oncology. The aim of this review was to assess the applicability of these approaches in image-based oncological outcome prediction. EVIDENCE ACQUISITION: A systematic literature search was conducted using the databases MEDLINE through PubMed and Web of Science up to April 20, 2021. Studies investigating AI approaches to determine the risk of recurrence, metastasis, or survival directly from H&E-stained tissue sections in prostate, renal cell or urothelial carcinoma were included. Characteristics of the AI approach and performance metrics were extracted and summarized. Risk of bias (RoB) was assessed using the PROBAST tool. EVIDENCE SYNTHESIS: 16 studies yielding a total of 6658 patients and reporting on 17 outcome predictions were included. Six studies focused on renal cell, six on prostate and three on urothelial carcinoma while one study investigated renal cell and urothelial carcinoma. Handcrafted feature extraction was used in five, a convolutional neural network (CNN) in six and a deep feature extraction in four studies. One study compared a CNN with handcrafted feature extraction. In seven outcome predictions, a multivariable comparison with clinicopathological parameters was reported. Five of them showed statistically significant hazard ratios for the AI's model's-prediction. However, RoB was high in 15 outcome predictions and unclear in two. CONCLUSIONS: The included studies are promising but predominantly early pilot studies, therefore primarily highlighting the potential of AI approaches. Additional well-designed studies are needed to assess the actual clinical applicability.


Assuntos
Carcinoma de Células de Transição , Neoplasias da Bexiga Urinária , Urologia , Inteligência Artificial , Amarelo de Eosina-(YS) , Hematoxilina , Humanos , Masculino
8.
Nature ; 433(7022): 152-6, 2005 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-15650738

RESUMO

Developmental processes are thought to be highly complex, but there have been few attempts to measure and compare such complexity across different groups of organisms. Here we introduce a measure of biological complexity based on the similarity between developmental and computer programs. We define the algorithmic complexity of a cell lineage as the length of the shortest description of the lineage based on its constituent sublineages. We then use this measure to estimate the complexity of the embryonic lineages of four metazoan species from two different phyla. We find that these cell lineages are significantly simpler than would be expected by chance. Furthermore, evolutionary simulations show that the complexity of the embryonic lineages surveyed is near that of the simplest lineages evolvable, assuming strong developmental constraints on the spatial positions of cells and stabilizing selection on cell number. We propose that selection for decreased complexity has played a major role in moulding metazoan cell lineages.


Assuntos
Evolução Biológica , Linhagem da Célula , Rhabditoidea/citologia , Rhabditoidea/embriologia , Urocordados/citologia , Urocordados/embriologia , Algoritmos , Animais , Caenorhabditis elegans/citologia , Caenorhabditis elegans/embriologia , Simulação por Computador , Modelos Biológicos
9.
Arch Dis Child ; 102(6): 535-542, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28104626

RESUMO

BACKGROUND: Deformational plagiocephaly (DP) is one of the most prevalent abnormal findings in infants and a frequent reason for parents to seek paediatric advice. OBJECTIVE: To systematically review the literature and identify evidence and hypotheses on the aetiology and determinants of DP in otherwise healthy infants. DESIGN: Systematic keyword search in all major biomedical databases to identify peer-reviewed publications reporting (a) empirical research or (b) hypotheses on the aetiology of DP in healthy, term infants. 3150 studies published between 1985 and 2016 and containing relevant keywords were screened. In a two-pronged approach, results were summarised separately for the body of empirical work (22 studies) and the body of hypotheses (110 articles). REVIEW FINDINGS: Only a few empirical studies have examined risk factors in non-selected patient populations on a higher grade methodological level. The most commonly reported risk factors were: male gender, supine sleep position, limited neck rotation or preference in head position, first-born child, lower level of activity and lack of tummy time. Agreement between empirical studies was poor for most exposures, including supine sleep position, tummy time and use of car seats. The articles reporting hypotheses on the aetiology of DP cover a wide field of environmental and biological factors, but include little suggestions as to the potential influence of the everyday care environment of the baby. CONCLUSIONS AND RELEVANCE: The evidence on the aetiology of DP is fragmentary and heterogeneous. In addition, factors possibly relevant to the development of DP have not been appreciated in the scientific discussion.


Assuntos
Plagiocefalia não Sinostótica/etiologia , Exercício Físico/fisiologia , Feminino , Movimentos da Cabeça/fisiologia , Humanos , Lactente , Masculino , Plagiocefalia não Sinostótica/fisiopatologia , Fatores de Risco , Fatores Sexuais , Decúbito Dorsal/fisiologia
10.
Crit Care Med ; 30(11): 2473-80, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12441757

RESUMO

OBJECTIVE: Animal studies have demonstrated that reperfusion disorders occurring after cardiac arrest affect outcome. Reperfusion injury can be caused by activation of complement, polymorphonuclear leukocytes (PMN), and PMN-endothelial interaction. We studied different specific markers of these processes during and after cardiopulmonary resuscitation in humans. DESIGN: Prospective clinical trial. SETTING: University hospital. PATIENTS: A total of 55 patients who underwent out-of-hospital cardiopulmonary resuscitation for nontraumatic causes. INTERVENTIONS: Blood samples were drawn immediately, 15 mins, and 30 mins after initiation of cardiopulmonary resuscitation. In the case of restoration of spontaneous circulation, additional blood samples were taken at serial time points until 7 days after cardiac arrest. MEASUREMENTS AND MAIN RESULTS: A marked activation of complement and PMN was found in all patients investigated. Serum concentrations of specific activation markers of the complement system, anaphylatoxin C3a and the soluble membrane attack complex SC5b-9, and PMN elastase were increased during cardiopulmonary resuscitation and for

Assuntos
Reanimação Cardiopulmonar , Moléculas de Adesão Celular/metabolismo , Ativação do Complemento , Parada Cardíaca/fisiopatologia , Ativação de Neutrófilo , Traumatismo por Reperfusão/imunologia , Idoso , Anafilatoxinas/metabolismo , Biomarcadores , Estudos de Casos e Controles , Complexo de Ataque à Membrana do Sistema Complemento/metabolismo , Feminino , Parada Cardíaca/terapia , Humanos , Molécula 1 de Adesão Intercelular/sangue , Elastase de Leucócito/sangue , Masculino , Pessoa de Meia-Idade , Selectina-P/sangue , Estudos Prospectivos , Estatísticas não Paramétricas
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