Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 13 de 13
Filtrar
2.
Medicine (Baltimore) ; 102(25): e34146, 2023 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-37352047

RESUMO

BACKGROUND: This meta-analysis compared the effects of intravenous Tranexamic acid (TXA) and a placebo on hemostasis, hospital course, and complications in adult patients undergoing various urologic surgeries. METHODS: The literature was extensively searched using various databases. The primary outcomes were standardized mean differences (SMDs) of intraoperative blood loss and odds ratios (ORs) of necessary blood product transfusion. The secondary outcomes included SMDs of operative time, SMDs of decreased hemoglobulin levels at 24 hours after surgery, and ORs of thromboembolic events. RESULTS: The meta-analysis included 13 randomized controlled trials (RCT) comprising 1814 participants in total. The SMD of intraoperative blood loss for TXA versus placebo was -0.705 (95% confidence interval [CI]: -1.113 to -0.297). The pooled ORs of transfusion in the TXA group compared with the placebo group was 0.426 (95% CI: 0.290-0.625). These findings indicated a significantly lower intraoperative blood loss and a reduced need for transfusion following intravenous TXA. The pooled ORs of thromboembolic events in the TXA group compared with the placebo group was 0.664 (95% CI: 0.146-3.024). CONCLUSIONS: Intravenous TXA can reduce intraoperative blood loss, decrease the need for transfusion, and shorten operative time, and it does not increase the risk of thromboembolic events.


Assuntos
Antifibrinolíticos , Tromboembolia , Ácido Tranexâmico , Humanos , Perda Sanguínea Cirúrgica/prevenção & controle , Ensaios Clínicos Controlados Aleatórios como Assunto , Tromboembolia/prevenção & controle
3.
Healthcare (Basel) ; 11(10)2023 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-37239677

RESUMO

BACKGROUND: One of the most severe complications of liposuction and fat grafting is pulmonary fat embolism (PFE). However, most healthcare workers are not familiar with PFE. We performed a systematic review to describe the details of PFE. METHODS: PubMed, EMBASE, and Google Scholar were searched up to October 2022. Further analysis focused on clinical, diagnostic, and outcome parameters. RESULTS: A total of 40 patients from 19 countries were included. Chest computed tomography (CT) yielded 100% accuracy in the diagnosis of PFE. More than 90% of the deceased died within 5 days after surgery, and in 69% of patients, onset of symptoms occurred within 24 h after surgery. The proportions of patients who required mechanical ventilation, had a cardiac arrest event, or died among all patients and among those whose onset of symptoms occurred within 24 h after surgery were 76%, 38%, and 34% versus 86%, 56%, and 54%, respectively. CONCLUSIONS: The earlier the onset of symptoms was, the more severe the clinical course was. Once a patient presents with PFE-related symptoms, surgery should be halted, supportive care initiated, and chest CT used to diagnose PFE. According to our review results, if a patient with PFE survives the initial episode without permanent sequelae, a complete recovery can be anticipated.

4.
Medicina (Kaunas) ; 58(10)2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36295540

RESUMO

Background and Objectives: We developed a machine learning algorithm to analyze trauma-related data and predict the mortality and chronic care needs of patients with trauma. Materials and Methods: We recruited admitted patients with trauma during 2015 and 2016 and collected their clinical data. Then, we subjected this database to different machine learning techniques and chose the one with the highest accuracy by using cross-validation. The primary endpoint was mortality, and the secondary endpoint was requirement for chronic care. Results: Data of 5871 patients were collected. We then used the eXtreme Gradient Boosting (xGBT) machine learning model to create two algorithms: a complete model and a short-term model. The complete model exhibited an 86% recall for recovery, 30% for chronic care, 67% for mortality, and 80% for complications; the short-term model fitted for ED displayed an 89% recall for recovery, 25% for chronic care, and 41% for mortality. Conclusions: We developed a machine learning algorithm that displayed good recall for the healthy recovery group but unsatisfactory results for those requiring chronic care or having a risk of mortality. The prediction power of this algorithm may be improved by implementing features such as age group classification, severity selection, and score calibration of trauma-related variables.


Assuntos
Algoritmos , Aprendizado de Máquina , Humanos , Prognóstico , Hospitalização , Estudos Retrospectivos
5.
Healthcare (Basel) ; 10(5)2022 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-35627927

RESUMO

Smartphones are currently extensively used worldwide, and advances in hardware quality have engendered improvements in smartphone image quality, which is occasionally comparable to the quality of medical imaging systems. This paper proposes two algorithms for pupil recognition: a stateful-service-based pupil recognition mechanism and color component low-pass filtering algorithm. The PRSSM algorithm can determine pupil diameters in images captured in indoor natural light environments, and the CCLPF algorithm can determine pupil diameters in those captured outdoors under sunlight. The PRSSM algorithm converts RGB colors into the hue saturation value color space and performs adaptive thresholding, morphological operations, and contour detection for effectively analyzing the diameter of the pupil. The CCLPF algorithm derives the average matrix for the red components of eye images captured in outdoor environments. It also performs low-pass filtering, morphological and contour detection operations, and rule-of-thumb correction. This algorithm can effectively analyze pupil diameter in outdoor natural light. Traditional ruler-based measurements of pupil diameter were used as the reference to verify the accuracy of the PRSSM and CCLPF algorithms and to compare their accuracy with that of the other algorithm. The errors in pupil diameter data were smaller for the PRSSM and CCLPF algorithms than for the other algorithm.

6.
Medicine (Baltimore) ; 100(49): e27753, 2021 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-34889225

RESUMO

ABSTRACT: In an overcrowded emergency department (ED), trauma surgeons and emergency physicians need an accurate prognostic predictor for critical decision-making involving patients with severe trauma. We aimed to develope a machine learning-based early prognostic model based on admission features and initial ED management.We only recruited patients with severe trauma (defined as an injury severity score >15) as the study cohort and excluded children (defined as patients <16 years old) from a 4-years database (Chi-Mei Medical Center, from January 2015, to December 2018) recording the clinical features of all admitted trauma patients. We considered only patient features that could be determined within the first 2 hours after arrival to the ED. These variables included Glasgow Coma Scale (GCS) score; heart rate; respiratory rate; mean arterial pressure (MAP); prehospital cardiac arrest; abbreviated injury scales (AIS) of head and neck, thorax, and abdomen; and ED interventions (tracheal intubation/tracheostomy, blood product transfusion, thoracostomy, and cardiopulmonary resuscitation). The endpoint for prognostic analyses was mortality within 7 days of admission.We divided the study cohort into the early death group (149 patients who died within 7 days of admission) and non-early death group (2083 patients who survived at >7 days of admission). The extreme Gradient Boosting (XGBoost) machine learning model provided mortality prediction with higher accuracy (94.0%), higher sensitivity (98.0%), moderate specificity (54.8%), higher positive predict value (PPV) (95.4%), and moderate negative predictive value (NPV) (74.2%).We developed a machine learning-based prognostic model that showed high accuracy, high sensitivity, and high PPV for predicting the mortality of patients with severe trauma.


Assuntos
Serviços Médicos de Emergência , Aprendizado de Máquina , Ferimentos e Lesões/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Escala de Coma de Glasgow , Humanos , Escala de Gravidade do Ferimento , Masculino , Pessoa de Meia-Idade , Admissão do Paciente , Prognóstico , Estudos Retrospectivos , Taiwan
8.
PLoS One ; 12(2): e0169432, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28146565

RESUMO

Planctomycetes are distinguished from other Bacteria by compartmentalization of cells via internal membranes, interpretation of which has been subject to recent debate regarding potential relations to Gram-negative cell structure. In our interpretation of the available data, the planctomycete Gemmata obscuriglobus contains a nuclear body compartment, and thus possesses a type of cell organization with parallels to the eukaryote nucleus. Here we show that pore-like structures occur in internal membranes of G.obscuriglobus and that they have elements structurally similar to eukaryote nuclear pores, including a basket, ring-spoke structure, and eight-fold rotational symmetry. Bioinformatic analysis of proteomic data reveals that some of the G. obscuriglobus proteins associated with pore-containing membranes possess structural domains found in eukaryote nuclear pore complexes. Moreover, immunogold labelling demonstrates localization of one such protein, containing a ß-propeller domain, specifically to the G. obscuriglobus pore-like structures. Finding bacterial pores within internal cell membranes and with structural similarities to eukaryote nuclear pore complexes raises the dual possibilities of either hitherto undetected homology or stunning evolutionary convergence.


Assuntos
Bactérias/ultraestrutura , Poro Nuclear/ultraestrutura , Bactérias/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Evolução Biológica , Compartimento Celular , Parede Celular/metabolismo , Biologia Computacional/métodos , Eucariotos/ultraestrutura , Imageamento Tridimensional , Membranas Intracelulares/ultraestrutura , Modelos Moleculares , Planctomycetales/ultraestrutura , Conformação Proteica , Proteoma , Proteômica
9.
Appl Opt ; 54(15): 4617-22, 2015 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-26192493

RESUMO

We report a high-efficiency quantum dot (QD) film for high color gamut edge-lit LCD backlights. On the film's input surface, an array of asymmetric microprisms is used to preserve the large off-axis angle of the incident blue light. On the exit surface, the retroreflective microprisms retain blue light inside the film. The extended optical path effectively enhances the blue light's probability to hit QDs and generate downconverted wavelengths. When not using any volume scattering particles, fewer QDs are needed to re-emit higher power green and red light, which helps lower the material cost.

10.
PLoS One ; 9(3): e91344, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24632833

RESUMO

Members of phylum Planctomycetes have been proposed to possess atypical cell organisation for the Bacteria, having a structure of sectioned cells consistent with internal compartments surrounded by membranes. Here via electron tomography we confirm the presence of compartments in the planctomycete Gemmata obscuriglobus cells. Resulting 3-D models for the most prominent structures, nuclear body and riboplasm, demonstrate their entirely membrane - enclosed nature. Immunogold localization of the FtsK protein also supports the internal organisation of G.obscuriglobus cells and their unique mechanism of cell division. We discuss how these new data expand our knowledge on bacterial cell biology and suggest evolutionary consequences of the findings.


Assuntos
Compartimento Celular , Planctomycetales/ultraestrutura , Proteínas de Bactérias/metabolismo , Parede Celular/ultraestrutura , Espaço Intracelular/metabolismo , Planctomycetales/metabolismo , Transporte Proteico
11.
Proc Natl Acad Sci U S A ; 107(29): 12883-8, 2010 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-20566852

RESUMO

Endocytosis is a process by which extracellular material such as macromolecules can be incorporated into cells via a membrane-trafficking system. Although universal among eukaryotes, endocytosis has not been identified in Bacteria or Archaea. However, intracellular membranes are known to compartmentalize cells of bacteria in the phylum Planctomycetes, suggesting the potential for endocytosis and membrane trafficking in members of this phylum. Here we show that cells of the planctomycete Gemmata obscuriglobus have the ability to uptake proteins present in the external milieu in an energy-dependent process analogous to eukaryotic endocytosis, and that internalized proteins are associated with vesicle membranes. Occurrence of such ability in a bacterium is consistent with autogenous evolution of endocytosis and the endomembrane system in an ancestral noneukaryote cell.


Assuntos
Bactérias/citologia , Bactérias/metabolismo , Proteínas de Bactérias/metabolismo , Endocitose , Bactérias/ultraestrutura , Evolução Biológica , Compartimento Celular , DNA Bacteriano/metabolismo , Metabolismo Energético , Proteínas de Fluorescência Verde , Processamento de Proteína Pós-Traducional , Vesículas Transportadoras/ultraestrutura
12.
BMC Microbiol ; 9: 5, 2009 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-19133117

RESUMO

BACKGROUND: The phylum Verrucomicrobia is a divergent phylum within domain Bacteria including members of the microbial communities of soil and fresh and marine waters; recently extremely acidophilic members from hot springs have been found to oxidize methane. At least one genus, Prosthecobacter, includes species with genes homologous to those encoding eukaryotic tubulins. A significant superphylum relationship of Verrucomicrobia with members of phylum Planctomycetes possessing a unique compartmentalized cell plan, and members of the phylum Chlamydiae including human pathogens with a complex intracellular life cycle, has been proposed. Based on the postulated superphylum relationship, we hypothesized that members of the two separate phyla Planctomycetes and Verrucomicrobia might share a similar ultrastructure plan differing from classical prokaryote organization. RESULTS: The ultrastructure of cells of four members of phylum Verrucomicrobia - Verrucomicrobium spinosum, Prosthecobacter dejongeii, Chthoniobacter flavus, and strain Ellin514 - was examined using electron microscopy incorporating high-pressure freezing and cryosubstitution. These four members of phylum Verrucomicrobia, representing 3 class-level subdivisions within the phylum, were found to possess a compartmentalized cell plan analogous to that found in phylum Planctomycetes. Like all planctomycetes investigated, they possess a major pirellulosome compartment containing a condensed nucleoid and ribosomes surrounded by an intracytoplasmic membrane (ICM), as well as a ribosome-free paryphoplasm compartment between the ICM and cytoplasmic membrane. CONCLUSION: A unique compartmentalized cell plan so far found among Domain Bacteria only within phylum Planctomycetes, and challenging our concept of prokaryote cell plans, has now been found in a second phylum of the Domain Bacteria, in members of phylum Verrucomicrobia. The planctomycete cell plan thus occurs in at least two distinct phyla of the Bacteria, phyla which have been suggested from other evidence to be related phylogenetically in the proposed PVC (Planctomycetes-Verrucomicrobia-Chlamydiae) superphylum. This planctomycete cell plan is present in at least 3 of 6 subdivisions of Verrucomicrobia, suggesting that the common ancestor of the verrucomicrobial phylum was also compartmentalized and possessed such a plan. The presence of this compartmentalized cell plan in both phylum Planctomycetes and phylum Verrucomicrobia suggest that the last common ancestor of these phyla was also compartmentalized.


Assuntos
Bactérias/ultraestrutura , Compartimento Celular , Filogenia , Bactérias/classificação , Bactérias/citologia , Bactérias/genética , Citoplasma/ultraestrutura , DNA Bacteriano/análise , Membranas Intracelulares/microbiologia , Membranas Intracelulares/ultraestrutura , Microscopia Eletrônica de Transmissão , Ribossomos/microbiologia
13.
BMC Cell Biol ; 10: 4, 2009 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-19144151

RESUMO

BACKGROUND: Gemmata obscuriglobus is a distinctive member of the divergent phylum Planctomycetes, all known members of which are peptidoglycan-less bacteria with a shared compartmentalized cell structure and divide by a budding process. G. obscuriglobus in addition shares the unique feature that its nucleoid DNA is surrounded by an envelope consisting of two membranes forming an analogous structure to the membrane-bounded nucleoid of eukaryotes and therefore G. obscuriglobus forms a special model for cell biology. Draft genome data for G. obscuriglobus as well as complete genome sequences available so far for other planctomycetes indicate that the key bacterial cell division protein FtsZ is not present in these planctomycetes, so the cell division process in planctomycetes is of special comparative interest. The membrane-bounded nature of the nucleoid in G. obscuriglobus also suggests that special mechanisms for the distribution of this nuclear body to the bud and for distribution of chromosomal DNA might exist during division. It was therefore of interest to examine the cell division cycle in G. obscuriglobus and the process of nucleoid distribution and nuclear body formation during division in this planctomycete bacterium via light and electron microscopy. RESULTS: Using phase contrast and fluorescence light microscopy, and transmission electron microscopy, the cell division cycle of G. obscuriglobus was determined. During the budding process, the bud was formed and developed in size from one point of the mother cell perimeter until separation. The matured daughter cell acted as a new mother cell and started its own budding cycle while the mother cell can itself initiate budding repeatedly. Fluorescence microscopy of DAPI-stained cells of G. obscuriglobus suggested that translocation of the nucleoid and formation of the bud did not occur at the same time. Confocal laser scanning light microscopy applied to cells stained for membranes as well as DNA confirmed the behaviour of the nucleoid and nucleoid envelope during cell division. Electron microscopy of cryosubstituted cells confirmed deductions from light microscopy concerning nucleoid presence in relation to the stage of budding, and showed that the nucleoid was observed to occur in both mother and bud cells only at later budding stages. It further suggested that nucleoid envelope formed only after the nucleoid was translocated into the bud, since envelopes only appeared in more mature buds, while naked nucleoids occurred in smaller buds. Nucleoid envelope appeared to originate from the intracytoplasmic membranes (ICM) of both mother cell and bud. There was always a connecting passage between mother cell and bud during the budding process until separation of the two cells. The division cycle of the nucleated planctomycete G. obscuriglobus appears to be a complex process in which chromosomal DNA is transported to the daughter cell bud after initial formation of the bud, and this can be performed repeatedly by a single mother cell. CONCLUSION: The division cycle of the nucleated planctomycete G. obscuriglobus is a complex process in which chromosomal nucleoid DNA is transported to the daughter cell bud after initial formation of a bud without nucleoid. The new bud nucleoid is initially naked and not surrounded by membrane, but eventually acquires a complete nucleoid envelope consisting of two closely apposed membranes as occurs in the mother cell. The membranes of the new nucleoid envelope surrounding the bud nucleoid are derived from intracytoplasmic membranes of both the mother cell and the bud. The cell division of G. obscuriglobus displays some unique features not known in cells of either prokaryotes or eukaryotes.


Assuntos
Bactérias/citologia , Compartimento Celular/fisiologia , Ciclo Celular/genética , Bactérias/genética , Microscopia Confocal , Microscopia Eletrônica de Transmissão , Microscopia de Fluorescência , Microscopia de Contraste de Fase
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA