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1.
South Med J ; 117(7): 358-363, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38959961

RESUMO

OBJECTIVES: Periodically, medical publications are retracted. The reasons vary from minor situations, such as author attributions, which do not undermine the validity of the data or the analysis in the article, to serious reasons, such as fraud. Understanding the reasons for retraction can provide important information for clinicians, educators, researchers, journals, and editorial boards. METHODS: The PubMed database was searched using the term "COVID-19" (coronavirus disease 2019) and the term limitation "retracted publication." The characteristics of the journals with retracted articles, the types of article, and the reasons for retraction were analyzed. RESULTS: This search recovered 196 articles that had been retracted. These retractions were published in 179 different journals; 14 journals had >1 retracted article. The mean impact factor of these journals was 8.4, with a range of 0.32-168.9. The most frequent reasons for retractions were duplicate publication, concerns about data validity and analysis, concerns about peer review, author request, and the lack of permission or ethical violation. There were significant differences between the types of article and the reasons for retraction but no consistent pattern. A more detailed analysis of two particular retractions demonstrates the complexity and the effort required to make decisions about article retractions. CONCLUSIONS: The retraction of published articles presents a significant challenge to journals, editorial boards, peer reviewers, and authors. This process has the potential to provide important benefits; it also has the potential to undermine confidence in both research and the editorial process.


Assuntos
COVID-19 , Publicações Periódicas como Assunto , PubMed , Retratação de Publicação como Assunto , Humanos , COVID-19/epidemiologia , Publicações Periódicas como Assunto/estatística & dados numéricos , SARS-CoV-2 , Fator de Impacto de Revistas , Má Conduta Científica
2.
Int J Mol Sci ; 25(14)2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39063156

RESUMO

Autologous platelet-rich plasma (PRP) preparations are prepared at the point of care. Centrifugation cellular density separation sequesters a fresh unit of blood into three main fractions: a platelet-poor plasma (PPP) fraction, a stratum rich in platelets (platelet concentrate), and variable leukocyte bioformulation and erythrocyte fractions. The employment of autologous platelet concentrates facilitates the biological potential to accelerate and support numerous cellular activities that can lead to tissue repair, tissue regeneration, wound healing, and, ultimately, functional and structural repair. Normally, after PRP preparation, the PPP fraction is discarded. One of the less well-known but equally important features of PPP is that particular growth factors (GFs) are not abundantly present in PRP, as they reside outside of the platelet alpha granules. Precisely, insulin-like growth factor-1 (IGF-1) and hepatocyte growth factor (HGF) are mainly present in the PPP fraction. In addition to their roles as angiogenesis activators, these plasma-based GFs are also known to inhibit inflammation and fibrosis, and they promote keratinocyte migration and support tissue repair and wound healing. Additionally, PPP is known for the presence of exosomes and other macrovesicles, exerting cell-cell communication and cell signaling. Newly developed ultrafiltration technologies incorporate PPP processing methods by eliminating, in a fast and efficient manner, plasma water, cytokines, molecules, and plasma proteins with a molecular mass (weight) less than the pore size of the fibers. Consequently, a viable and viscous protein concentrate of functional total proteins, like fibrinogen, albumin, and alpha-2-macroglobulin is created. Consolidating a small volume of high platelet concentrate with a small volume of highly concentrated protein-rich PPP creates a protein-rich, platelet-rich plasma (PR-PRP) biological preparation. After the activation of proteins, mainly fibrinogen, the PR-PRP matrix retains and facilitates interactions between invading resident cells, like macrophages, fibroblast, and mesenchymal stem cells (MSCs), as well as the embedded concentrated PRP cells and molecules. The administered PR-PRP biologic will ultimately undergo fibrinolysis, leading to a sustained release of concentrated cells and molecules that have been retained in the PR-PRP matrix until the matrix is dissolved. We will discuss the unique biological and tissue reparative and regenerative properties of the PR-PRP matrix.


Assuntos
Plasma Rico em Plaquetas , Cicatrização , Humanos , Plasma Rico em Plaquetas/metabolismo , Plasma Rico em Plaquetas/química , Regeneração , Animais , Plaquetas/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo
3.
Proc (Bayl Univ Med Cent) ; 37(3): 459-464, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38628334

RESUMO

Background: The retraction of medical articles periodically occurs in most medical journals and can involve multiple article types. These retractions are beneficial if they remove flawed or fraudulent information from the medical literature. However, retractions may also decrease confidence in the medical literature and require significant amounts of time by editors. Methods: One publisher (Hindawi) announced that it will retract over 1200 articles. Given this, the PubMed database was searched to identify retracted publications on or related to COVID-19, and articles retracted by journals sponsored by the publisher Hindawi were then identified. Results: These journals retracted 25 articles and, in most cases, did not provide an exact explanation about the particular problem(s) resulting in the retraction. The time to retraction was 468.7 ± 109.8 days (median = 446 days). These articles had 9.3 ± 9.9 citations. Conclusion: Analysis of the titles and abstracts of the articles suggests that their removal from the medical literature would have limited effects on the near-term management decisions during the COVID-19 pandemic. Nevertheless, retraction of medical articles creates uncertainty in medical care and science and in the public regarding the validity of medical research and related publications and the level of professionalism of the individuals submitting these articles.

4.
Viruses ; 14(9)2022 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-36146663

RESUMO

Respiratory pathogens can be spread though the transmission of aerosolised expiratory secretions in the form of droplets or particulates. Understanding the fundamental aerosol parameters that govern how such pathogens survive whilst airborne is essential to understanding and developing methods of restricting their dissemination. Pathogen viability measurements made using Controlled Electrodynamic Levitation and Extraction of Bioaerosol onto Substrate (CELEBS) in tandem with a comparative kinetics electrodynamic balance (CKEDB) measurements allow for a direct comparison between viral viability and evaporation kinetics of the aerosol with a time resolution of seconds. Here, we report the airborne survival of mouse hepatitis virus (MHV) and determine a comparable loss of infectivity in the aerosol phase to our previous observations of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Through the addition of clinically relevant concentrations of mucin to the bioaerosol, there is a transient mitigation of the loss of viral infectivity at 40% RH. Increased concentrations of mucin promoted heterogenous phase change during aerosol evaporation, characterised as the formation of inclusions within the host droplet. This research demonstrates the role of mucus in the aerosol phase and its influence on short-term airborne viral stability.


Assuntos
COVID-19 , SARS-CoV-2 , Animais , Camundongos , Viabilidade Microbiana , Mucinas , Aerossóis e Gotículas Respiratórios
5.
Stem Cells Transl Med ; 8(12): 1265-1271, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31599497

RESUMO

The stromal vascular fraction (SVF) is a heterogeneous population of stem/stromal cells isolated from perivascular and extracellular matrix (ECM) of adipose tissue complex (ATC). Administration of SVF holds a strong therapeutic potential for regenerative and wound healing medicine applications aimed at functional restoration of tissues damaged by injuries or chronic diseases. SVF is commonly divided into cellular stromal vascular fraction (cSVF) and tissue stromal vascular fraction (tSVF). Cellular SVF is obtained from ATC by collagenase digestion, incubation/isolation, and pelletized by centrifugation. Enzymatic disaggregation may alter the relevant biological characteristics of adipose tissue, while providing release of complex, multiattachment of cell-to-cell and cell-to-matrix, effectively eliminating the bioactive ECM and periadventitial attachments. In many countries, the isolation of cellular elements is considered as a "more than minimal" manipulation, and is most often limited to controlled clinical trials and subject to regulatory review. Several alternative, nonenzymatic methods of adipose tissue processing have been developed to obtain via minimal mechanical manipulation an autologous tSVF product intended for delivery, reducing the procedure duration, lowering production costs, decreasing regulatory burden, and shortening the translation into the clinical setting. Ideally, these procedures might allow for the integration of harvesting and processing of adipose tissue for ease of injection, in a single procedure utilizing a nonexpanded cellular product at the point of care, while permitting intraoperative autologous cellular and tissue-based therapies. Here, we review and discuss the options, advantages, and limitations of the major strategies alternative to enzymatic processing currently developed for minimal manipulation of adipose tissue. Stem Cells Translational Medicine 2019;8:1265&1271.


Assuntos
Tecido Adiposo/citologia , Separação Celular/métodos , Terapia Baseada em Transplante de Células e Tecidos/métodos , Matriz Extracelular/fisiologia , Células-Tronco/citologia , Diferenciação Celular , Humanos , Cicatrização
6.
Phys Med Rehabil Clin N Am ; 27(4): 871-891, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27788905

RESUMO

"Using your own tissues to heal" represents a major health care paradigm change and is one of the most exciting minimally invasive options currently available. Biocellular regenerative therapies are rapidly improving in documentation and cellular analyses and are gaining good safety and efficacy profiles. Once considered purely experimental, they have entered into an accepted, translational period to clinical providers, backed by improving science supporting the basic hypotheses. It is a well-recognized and reported alternative to many traditional medical/surgical interventions.


Assuntos
Tecido Adiposo/citologia , Medicina Regenerativa , Células Estromais/fisiologia , Diferenciação Celular , Humanos
7.
Artigo em Inglês | MEDLINE | ID: mdl-23630430

RESUMO

OBJECTIVES: Provide background for use of acquiring autologous adipose tissue as a tissue graft and source of adult progenitor cells for use in cosmetic plastic surgery. Discuss the background and mechanisms of action of closed syringe vacuum lipoaspiration, with emphasis on accessing adipose-derived mesenchymal/stromal cells and the stromal vascular fraction (SVF) for use in aesthetic, structural reconstruction and regenerative applications. Explain a proven protocol for acquiring high-quality autologous fat grafts (AFG) with use of disposable, microcannula systems. DESIGN: Explain the components and advantage of use of the patented super luer-lock and microcannulas system for use with the closed-syringe system. A sequential explanation of equipment selection for minimally traumatic lipoaspiration in small volumes is presented, including use of blunt injection cannulas to reduce risk of embolism. RESULTS: Thousands of AFG have proven safe and efficacious for lipoaspiration techniques for large and small structural fat grafting procedures. The importance and advantages of gentle harvesting of the adipose tissue complex has become very clear in the past 5 years. The closed-syringe system offers a minimally invasive, gentle system with which to mobilize subdermal fat tissues in a suspension form. Resulting total nuclear counting of undifferentiated cells of the adipose-derived -SVF suggests that the yield achieved is better than use of always-on, constant mechanical pump applied vacuum systems. CONCLUSION: Use of a closed-syringe lipoaspiration system featuring disposable microcannulas offers a safe and effective means of harvesting small volumes of nonmanipulated adipose tissues and its accompanying progenitor cells within the SVF. Closed syringes and microcannulas are available as safe, sterile, disposable, compact systems for acquiring high-quality AFG. Presented is a detailed, step-by-step, proven protocol for performing quality autologous structural adipose transplantation.

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