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1.
Annu Rev Biochem ; 91: 475-504, 2022 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-35320685

RESUMO

Molybdenum- and tungsten-dependent proteins catalyze essential processes in living organisms and biogeochemical cycles. Among these enzymes, members of the dimethyl sulfoxide (DMSO) reductase superfamily are considered the most diverse, facilitating a wide range of chemical transformations that can be categorized as oxygen atom installation, removal, and transfer. Importantly, DMSO reductase enzymes provide high efficiency and excellent selectivity while operating under mild conditions without conventional oxidants such as oxygen or peroxides. Despite the potential utility of these enzymes as biocatalysts, such applications have not been fully explored. In addition, the vast majority of DMSO reductase enzymes still remain uncharacterized. In this review, we describe the reactivities, proposed mechanisms, and potential synthetic applications of selected enzymes in the DMSO reductase superfamily. We also highlight emerging opportunities to discover new chemical activity and current challenges in studying and engineering proteins in the DMSO reductase superfamily.


Assuntos
Proteínas Ferro-Enxofre , Oxirredutases , Proteínas Ferro-Enxofre/genética , Proteínas Ferro-Enxofre/metabolismo , Oxirredutases/metabolismo , Oxigênio/metabolismo , Tungstênio/metabolismo
2.
BMC Plant Biol ; 24(1): 440, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38778295

RESUMO

BACKGROUND: Exploring the relationship between parasitic plants and answering taxonomic questions is still challenging. The subtribe Scurrulinae (Loranthaceae), which has a wide distribution in Asia and Africa, provides an excellent example to illuminate this scenario. Using a comprehensive taxon sampling of the subtribe, this study focuses on infer the phylogenetic relationships within Scurrulinae, investigate the phylogeny and biogeography of the subtribe, and establish a phylogenetically-based classification incorporating both molecular and morphological evidence. We conducted phylogenetic, historical biogeography, and ancestral character state reconstruction analyses of Scurrulinae based on the sequences of six DNA regions from 89 individuals to represent all five tribes of the Loranthaceae and the dataset from eleven morphological characters. RESULTS: The results strongly support the non-monophyletic of Scurrulinae, with Phyllodesmis recognized as a separate genus from its allies Taxillus and Scurrula based on the results from molecular data and morphological character reconstruction. The mistletoe Scurrulinae originated in Asia during the Oligocene. Scurrulinae was inferred to have been widespread in Asia but did not disperse to other areas. The African species of Taxillus, T. wiensii, was confirmed to have originated in Africa from African Loranthaceae ca. 17 Ma, and evolved independently from Asian members of Taxillus. CONCLUSIONS: This study based on comprehensive taxon sampling of the subtribe Scurrulinae, strongly supports the relationship between genera. The taxonomic treatment for Phyllodesmis was provided. The historical biogeography of mistletoe Scurrulinae was determined with origin in Asia during the Oligocene. Taxillus and Scurrula diverged during the climatic optimum in the middle Miocene. Taxillus wiensii originated in Africa from African Loranthaceae, and is an independent lineage from the Asian species of Taxillus. Diversification of Scurrulinae and the development of endemic species in Asia may have been supported by the fast-changing climate, including cooling, drying, and the progressive uplift of the high mountains in central Asia, especially during the late Pliocene and Pleistocene.


Assuntos
Loranthaceae , Filogenia , Filogeografia , Loranthaceae/genética , África , Ásia , Evolução Biológica , DNA de Plantas/genética , Evolução Molecular , Análise de Sequência de DNA
3.
Nature ; 554(7691): 234-238, 2018 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-29420476

RESUMO

High species diversity may result from recent rapid speciation in a 'cradle' and/or the gradual accumulation and preservation of species over time in a 'museum'. China harbours nearly 10% of angiosperm species worldwide and has long been considered as both a museum, owing to the presence of many species with hypothesized ancient origins, and a cradle, as many lineages have originated as recent topographic changes and climatic shifts-such as the formation of the Qinghai-Tibetan Plateau and the development of the monsoon-provided new habitats that promoted remarkable radiation. However, no detailed phylogenetic study has addressed when and how the major components of the Chinese angiosperm flora assembled to form the present-day vegetation. Here we investigate the spatio-temporal divergence patterns of the Chinese flora using a dated phylogeny of 92% of the angiosperm genera for the region, a nearly complete species-level tree comprising 26,978 species and detailed spatial distribution data. We found that 66% of the angiosperm genera in China did not originate until early in the Miocene epoch (23 million years ago (Mya)). The flora of eastern China bears a signature of older divergence (mean divergence times of 22.04-25.39 Mya), phylogenetic overdispersion (spatial co-occurrence of distant relatives) and higher phylogenetic diversity. In western China, the flora shows more recent divergence (mean divergence times of 15.29-18.86 Mya), pronounced phylogenetic clustering (co-occurrence of close relatives) and lower phylogenetic diversity. Analyses of species-level phylogenetic diversity using simulated branch lengths yielded results similar to genus-level patterns. Our analyses indicate that eastern China represents a floristic museum, and western China an evolutionary cradle, for herbaceous genera; eastern China has served as both a museum and a cradle for woody genera. These results identify areas of high species richness and phylogenetic diversity, and provide a foundation on which to build conservation efforts in China.


Assuntos
Biodiversidade , Magnoliopsida/classificação , Filogenia , China , Conservação dos Recursos Naturais/métodos , Evolução Molecular , Mapeamento Geográfico , Análise de Regressão , Análise Espaço-Temporal
4.
Childs Nerv Syst ; 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38722323

RESUMO

PURPOSE: To examine demographic and clinical characteristics and their association with survival in grade 2 and 3 pediatric meningiomas in a large cohort using the National Cancer Database (NCDB). METHODS: We conducted a comprehensive analysis using data from NCDB between 2004 to 2018. Tumor-specific data included tumor grade and size. Treatment details, including surgical resection, extent of resection, and radiotherapy, were gathered. Our analytic approach incorporated logistic and Poisson regression, Kaplan-Meier survival estimates, and Cox proportional hazards models. RESULTS: Among the included 239 patients aged 0-21 years, age category distribution was significantly different between grade 2 and grade 3 tumors (p = 0.018). For grade 2 meningiomas, 51.5% of patients were female, and 76.7% were white. 85.3% of patients with grade 2 meningiomas underwent surgical resection, of which 67% underwent gross total resection. Overall survival (OS) was significantly different between resected and non-resected patients (p = 0.048). Uninsured patients were over seven times as likely to have prolonged length of stay (LOS) versus those with private insurance (OR = 7.663, p = 0.014). For grade 3 meningiomas, 51.4% of patients were male, and 82.9% were white. 91.4% of patients with grade 3 meningiomas underwent surgical resection, of which 53.3% underwent subtotal resection. OS was not significantly different between resected and non-resected patients (p = 0.659). CONCLUSION: In summary, there were significant differences in age, maximum tumor dimension, unplanned readmission, radiotherapy, and treatment combinations between grade 2 and 3 meningiomas. These findings highlight the intricacies of managing pediatric meningiomas and emphasize the necessity for tailored therapeutic approaches to enhance outcomes in the future.

5.
Clin Oral Investig ; 28(6): 307, 2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38733524

RESUMO

PURPOSE: The factors related to pericoronitis severity are unclear, and this study aimed to address this knowledge gap. MATERIALS AND METHODS: In total, 113 patients with pericoronitis were included, and their demographic, clinical, and radiographic characteristics were recorded. The Patient-Clinician Pericoronitis Classification was used to score and categorize the severity of pericoronitis. Statistical analysis was conducted to examine the participants' characteristics, validity of the Patient-Clinician Pericoronitis Classification, and risk factors associated with the severity of pericoronitis. RESULTS: The demographic, clinical, and radiographic characteristics of males and females were similar, except for Winter's classification, pain, and intraoral swelling. The constructive validity of the Patient-Clinician Pericoronitis Classification was confirmed with three latent factors, including infection level, patient discomfort, and social interference. Ordinal logistic multivariate regression analysis revealed that upper respiratory tract infection was the sole risk factor associated with pericoronitis severity in males (odds ratio = 4.838). In females, pericoronitis on the right side (odds ratio = 2.486), distal radiolucency (odds ratio = 5.203), and menstruation (odds ratio = 3.416) were significant risk factors. CONCLUSION: This study demonstrated the constructive validity of the Patient-Clinician Pericoronitis Classification. Among females, pericoronitis in mandibular third molars on the right side with radiolucency in menstruating individuals was more severe. In males, upper respiratory tract infection was the sole risk factor associated with pericoronitis severity. CLINICAL RELEVANCE: Individuals with risk factors should be aware of severe pericoronitis in the coming future.


Assuntos
Dente Serotino , Pericoronite , Índice de Gravidade de Doença , Humanos , Masculino , Feminino , Fatores de Risco , Dente Serotino/diagnóstico por imagem , Pericoronite/complicações , Adulto , Adolescente , Mandíbula/diagnóstico por imagem
6.
Sensors (Basel) ; 23(12)2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37420704

RESUMO

Internet of Things (IoT) systems cooperative with unmanned aerial vehicles (UAVs) have been put into use for more than ten years, from transportation to military surveillance, and they have been shown to be worthy of inclusion in the next wireless protocols. Therefore, this paper studies user clustering and the fixed power allocation approach by placing multi-antenna UAV-mounted relays for extended coverage areas and achieving improved performance for IoT devices. In particular, the system enables UAV-mounted relays with multiple antennas together with non-orthogonal multiple access (NOMA) to provide a potential way to enhance transmission reliability. We presented two cases of multi-antenna UAVs such as maximum ratio transmission and the best selection to highlight the benefits of the antenna-selections approach with low-cost design. In addition, the base station managed its IoT devices in practical scenarios with and without direct links. For two cases, we derive closed-form expressions of outage probability (OP) and closed-form approximation ergodic capacity (EC) generated for both devices in the main scenario. The outage and ergodic capacity performances in some scenarios are compared to confirm the benefits of the considered system. The number of antennas was found to have a crucial impact on the performances. The simulation results show that the OP for both users strongly decreases when the signal-to-noise ratio (SNR), number of antennas, and fading severity factor of Nakagami-m fading increase. The proposed scheme outperforms the orthogonal multiple access (OMA) scheme in outage performance for two users. The analytical results match Monte Carlo simulations to confirm the exactness of the derived expressions.


Assuntos
Internet das Coisas , Militares , Humanos , Reprodutibilidade dos Testes , Análise por Conglomerados , Simulação por Computador
7.
J Neurooncol ; 160(1): 33-40, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35921021

RESUMO

INTRODUCTION: Cystic meningiomas are rare, accounting for 2-7% of all intracranial meningiomas. Little is known regarding whether these meningiomas behave differently compared to solid meningiomas. We sought to study this relatively uncommon imaging appearance of meningioma and to evaluate its clinical significance. METHODS: A single-institution retrospective cohort study of surgically-treated meningioma patients between 2000 and 2019 was conducted. Cystic meningioma was defined as a tumor with an intratumoral or peritumoral cyst present on preoperative imaging. Demographics, preoperative imaging, histopathology characteristics, operative data, and surgical outcomes were reviewed. Imaging variables, histopathology and outcomes were reported for cystic meningiomas and compared with non-cystic meningiomas. Univariate/multivariable analyses were conducted. RESULTS: Of 737 total meningiomas treated surgically, 38 (5.2%) were cystic. Gross total resection (GTR) was achieved in 84.2% of cystic meningioma patients. Eighty-two percent of cystic meningiomas were WHO grade I (n = 31), 15.7% were grade II and 2.6% were grade III. Most cystic meningiomas had low Ki-67/MIB-1 proliferation index (n = 24, 63.2%). A total of 18.4% (n = 7) patients with cystic meningioma had recurrence compared to 12.2% (n = 80) of patients with non-cystic meningioma (p = 0.228). No significant difference in median time to recurrence was observed between cystic and non-cystic meningiomas (25.4, Q1:13.9, Q3:46.9 months vs. 13.4, Q1:8.6, Q3:35.5 months, p = 0.080). CONCLUSIONS: A small portion of intracranial meningiomas have cystic characteristics on imaging. Cystic meningiomas are frequently WHO grade I, have low proliferation index, and had similar outcomes compared to non-cystic meningioma. Cysts in meningioma may not be a surrogate to determine aggressive meningioma behavior.


Assuntos
Cistos , Neoplasias Meníngeas , Meningioma , Humanos , Meningioma/diagnóstico por imagem , Meningioma/cirurgia , Meningioma/patologia , Neoplasias Meníngeas/diagnóstico por imagem , Neoplasias Meníngeas/cirurgia , Neoplasias Meníngeas/patologia , Estudos Retrospectivos , Cistos/patologia , Recidiva Local de Neoplasia/cirurgia
8.
Anesthesiology ; 134(6): 862-873, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33730169

RESUMO

BACKGROUND: Postoperative residual neuromuscular blockade related to nondepolarizing neuromuscular blocking agents may be associated with pulmonary complications. In this study, the authors sought to determine whether sugammadex was associated with a lower risk of postoperative pulmonary complications in comparison with neostigmine. METHODS: Adult patients from the Vanderbilt University Medical Center National Surgical Quality Improvement Program database who underwent general anesthesia procedures between January 2010 and July 2019 were included in an observational cohort study. In early 2017, a wholesale switch from neostigmine to sugammadex occurred at Vanderbilt University Medical Center. The authors therefore identified all patients receiving nondepolarizing neuromuscular blockades and reversal with neostigmine or sugammadex. An inverse probability of treatment weighting propensity score analysis approach was applied to control for measured confounding. The primary outcome was postoperative pulmonary complications, determined by retrospective chart review and defined as the composite of the three postoperative respiratory occurrences: pneumonia, prolonged mechanical ventilation, and unplanned intubation. RESULTS: Of 10,491 eligible cases, 7,800 patients received neostigmine, and 2,691 received sugammadex. A total of 575 (5.5%) patients experienced postoperative pulmonary complications (5.9% neostigmine vs. 4.2% sugammadex). Specifically, 306 (2.9%) patients had pneumonia (3.2% vs. 2.1%), 113 (1.1%) prolonged mechanical ventilation (1.1% vs. 1.1%), and 156 (1.5%) unplanned intubation (1.6% vs. 1.0%). After propensity score adjustment, the authors found a lower absolute incidence rate of postoperative pulmonary complications over time (adjusted odds ratio, 0.91 [per year]; 95% CI, 0.87 to 0.96; P < .001). No difference was observed on the odds of postoperative pulmonary complications in patients receiving sugammadex in comparison with neostigmine (adjusted odds ratio, 0.89; 95% CI, 0.65 to 1.22; P = 0.468). CONCLUSIONS: Among 10,491 patients at a single academic tertiary care center, the authors found that switching neuromuscular blockade reversal agents was not associated with the occurrence of postoperative pulmonary complications.


Assuntos
Inibidores da Colinesterase , Neostigmina , Adulto , Inibidores da Colinesterase/efeitos adversos , Estudos de Coortes , Humanos , Neostigmina/efeitos adversos , Sistema de Registros , Estudos Retrospectivos , Sugammadex/efeitos adversos
9.
Pediatr Blood Cancer ; 68(8): e29093, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34003588

RESUMO

Complex cranial vault reconstruction (CCVR) for pediatric craniosynostosis is a high blood loss surgery, for which antifibrinolytic agents have been shown to reduce bleeding and transfusion requirements. The relative efficacy of ε-aminocaproic acid (EACA) versus tranexamic acid (TXA) has not yet been evaluated in this population. The aim of this retrospective study was to compare perioperative blood loss and transfusion in CCVR patients receiving EACA versus TXA. In a CCVR cohort of 95 children, 47 received EACA and 48 received TXA. We found no differences in demographics, adverse outcomes, calculated blood loss (CBL), or transfusion requirements between the two antifibrinolytic groups.


Assuntos
Ácido Aminocaproico , Antifibrinolíticos , Craniossinostoses , Ácido Tranexâmico , Ácido Aminocaproico/uso terapêutico , Antifibrinolíticos/uso terapêutico , Perda Sanguínea Cirúrgica/prevenção & controle , Criança , Craniossinostoses/cirurgia , Humanos , Estudos Retrospectivos , Ácido Tranexâmico/uso terapêutico
10.
J Am Chem Soc ; 142(27): 11691-11697, 2020 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-32564602

RESUMO

Alkyl chlorides are bench-stable chemical feedstocks that remain among the most underutilized electrophile classes in transition metal catalysis. Overcoming intrinsic limitations of C(sp3)-Cl bond activation, we report the development of a novel organosilane reagent that can participate in chlorine atom abstraction under mild photocatalytic conditions. In particular, we describe the application of this mechanism to a dual nickel/photoredox catalytic protocol that enables the first cross-electrophile coupling of unactivated alkyl chlorides and aryl chlorides. Employing these low-toxicity, abundant, and commercially available organochloride building blocks, this methodology allows access to a broad array of highly functionalized C(sp2)-C(sp3) coupled adducts, including numerous drug analogues.


Assuntos
Hidrocarbonetos Clorados/química , Catálise , Estrutura Molecular , Níquel/química , Oxirredução , Processos Fotoquímicos
11.
Nature ; 505(7482): 239-43, 2014 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-24291791

RESUMO

The increasing demands placed on natural resources for fuel and food production require that we explore the use of efficient, sustainable feedstocks such as brown macroalgae. The full potential of brown macroalgae as feedstocks for commercial-scale fuel ethanol production, however, requires extensive re-engineering of the alginate and mannitol catabolic pathways in the standard industrial microbe Saccharomyces cerevisiae. Here we present the discovery of an alginate monomer (4-deoxy-L-erythro-5-hexoseulose uronate, or DEHU) transporter from the alginolytic eukaryote Asteromyces cruciatus. The genomic integration and overexpression of the gene encoding this transporter, together with the necessary bacterial alginate and deregulated native mannitol catabolism genes, conferred the ability of an S. cerevisiae strain to efficiently metabolize DEHU and mannitol. When this platform was further adapted to grow on mannitol and DEHU under anaerobic conditions, it was capable of ethanol fermentation from mannitol and DEHU, achieving titres of 4.6% (v/v) (36.2 g l(-1)) and yields up to 83% of the maximum theoretical yield from consumed sugars. These results show that all major sugars in brown macroalgae can be used as feedstocks for biofuels and value-added renewable chemicals in a manner that is comparable to traditional arable-land-based feedstocks.


Assuntos
Biocombustíveis/provisão & distribuição , Metabolismo dos Carboidratos , Etanol/metabolismo , Engenharia Genética , Phaeophyceae/metabolismo , Saccharomyces cerevisiae/metabolismo , Alginatos/metabolismo , Anaerobiose , Ascomicetos/genética , Ascomicetos/metabolismo , Biotecnologia , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Evolução Molecular , Fermentação , Teste de Complementação Genética , Ácido Glucurônico/metabolismo , Ácidos Hexurônicos/metabolismo , Manitol/metabolismo , Phaeophyceae/genética , Ácido Quínico/metabolismo , Reprodutibilidade dos Testes , Saccharomyces cerevisiae/genética , Alga Marinha/genética , Alga Marinha/metabolismo , Ácidos Urônicos/metabolismo
12.
Sensors (Basel) ; 20(2)2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-32284496

RESUMO

As one of key technologies of future networks, vehicle-to-everything (V2X) communication has recently been proposed to improve conventional vehicle systems in terms of traffic and communications. Main benefits of using V2X are efficient and safe traffic as well as low-latency communications and reliable massive connections. Non-orthogonal multiple access (NOMA) scheme was introduced as a promising solution in the fifth-generation (5G) mobile communications, by which quality-of-service (QoS) requirements of many 5G-enabled applications are satisfied as a result of improved network throughput and lower accessing and transmission latency. In this paper, we study NOMA-based communications between vehicles equipped with multiple antennas over Nakagami-m fading channels in V2X networks, in which uplink and downlink transmission between two vehicles with upper controller are supported by a road side unit (RSU) to increase the capacity rather than simply be connected to the base station. In the NOMA-V2X system under study, the outage probability depends on the power allocation factor of RSU transmission and the operation of successive interference cancellation (SIC) at vehicles. Analyses and simulations verify that the outage performance of NOMA-V2X system are mainly affected by fading parameters, levels of imperfect SIC, and power allocation factors.

13.
J Nurs Care Qual ; 35(1): 70-76, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-30973426

RESUMO

BACKGROUND: Incivility has been identified as a common occurrence in health care settings. While anecdotal evidence exists that these behaviors negatively impact patient care, more robust evidence is lacking. PURPOSE: This randomized controlled trial investigated the effects of exposure to incivility on clinical performance, teamwork, and emotions. METHODS: Teams of nurses were randomly assigned to a control or experimental group. The experimental group was exposed to incivility. Both groups were then prompted to perform basic life support on a high-fidelity manikin. Teams were scored on cardiopulmonary resuscitation (CPR) performance and teamwork. Individuals completed measures of affect and a cognitive test. RESULTS: There were no differences in CPR, cognitive or teamwork scores, or emotional state. However, 66% of the experimental group had a major error in their CPR performance. None of the control groups made the same error. CONCLUSIONS: These findings support anecdotal evidence that exposure to incivility may contribute to errors in clinical performance.


Assuntos
Reanimação Cardiopulmonar/normas , Incivilidade , Desempenho Profissional/normas , Adulto , Reanimação Cardiopulmonar/métodos , Competência Clínica/normas , Competência Clínica/estatística & dados numéricos , Feminino , Humanos , Relações Interpessoais , Masculino , Cuidados de Enfermagem/métodos , Cuidados de Enfermagem/normas , Cuidados de Enfermagem/estatística & dados numéricos , Desempenho Profissional/estatística & dados numéricos
14.
Int Microbiol ; 22(4): 437-449, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30895406

RESUMO

Azurin, a bacteriocin produced by a human gut bacterium Pseudomonas aeruginosa, can reveal selectively cytotoxic and induce apoptosis in cancer cells. After overcoming two phase I trials, a functional region of Azurin called p28 has been approved as a drug for the treatment of brain tumor glioma by FDA. The present study aims to improve a screening procedure and assess genetic diversity of Azurin genes in P. aeruginosa and Azurin-like genes in the gut microbiome of a specific population in Vietnam and global populations. Firstly, both cultivation-dependent and cultivation-independent techniques based on genomic and metagenomic DNAs extracted from fecal samples of the healthy specific population were performed and optimized to detect Azurin genes. Secondly, the Azurin gene sequences were analyzed and compared with global populations by using bioinformatics tools. Finally, the screening procedure improved from the first step was applied for screening Azurin-like genes, followed by the protein synthesis and NCI in vitro screening for anticancer activity. As a result, this study has successfully optimized the annealing temperatures to amplify DNAs for screening Azurin genes and applying to Azurin-like genes from human gut microbiota. The novelty of this study is the first of its kind to classify Azurin genes into five different genotypes at a global scale and confirm the potential anticancer activity of three Azurin-like synthetic proteins (Cnazu1, Dlazu11, and Ruazu12). The results contribute to the procedure development applied for screening anticancer proteins from human microbiome and a comprehensive understanding of their therapeutic response at a genetic level.


Assuntos
Azurina/genética , Microbioma Gastrointestinal , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/isolamento & purificação , Adolescente , Adulto , Azurina/metabolismo , Criança , Meios de Cultura/metabolismo , Fezes/microbiologia , Feminino , Variação Genética , Humanos , Masculino , Filogenia , Pseudomonas aeruginosa/crescimento & desenvolvimento , Pseudomonas aeruginosa/metabolismo , Adulto Jovem
15.
J Ultrasound Med ; 38(12): 3155-3161, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31037752

RESUMO

OBJECTIVES: To investigate the diagnostic accuracy and interobserver agreement among sonologists when assessing offline ultrasound (US) video sets of the "sliding sign" and among gynecologic surgeons when assessing corresponding laparoscopic video sets to predict pouch of Douglas (POD) obliteration and to compare the performance of the groups. METHODS: A diagnostic and reproducibility study was conducted, including 15 observers in 4 groups: (1) senior sonologists, (2) junior sonologists, (3) general gynecologists, and (4) advanced laparoscopists. The sonologists viewed 25 offline preoperative US video sets of the sliding sign, and the surgeons viewed the corresponding intraoperative laparoscopic videos of the same patients. Each observer was asked to classify POD obliteration in the video sets and was compared to the reference standard POD state determined at real-time laparoscopy by a single investigator (G.C.). The interobserver correlation and diagnostic accuracy were evaluated among the 15 observers and 4 groups. The Cohen κ coefficient and Fleiss κ coefficient were used for the analysis. RESULTS: The overall accuracy, sensitivity, specificity, positive predictive value, and negative predictive value for senior sonologists were 93.3%, 100%, 89.6%, 84.4%, and 100%, respectively; for junior sonologists, 70.0%, 88.9%, 59.4%, 55.2%, and 90.5%; for general gynecologists, 75.2%, 88.1%, 78.1%, 69.8%, and 91.9%; and for advanced laparoscopists, 82.4%, 91.9%, 90.8%, 82.9%, and 95.8%. The overall agreement between senior sonologists was almost perfect (Fleiss κ = 0.876); for junior sonologists and general gynecologists, it was moderate (Fleiss κ = 0.589 and 0.528); and for advanced laparoscopists, it was substantial (Fleiss κ = 0.652). CONCLUSIONS: Interobserver agreement was superior among senior sonologists. Prediction of POD obliteration using offline US videos by senior sonologists is comparable to offline assessments of laparoscopic videos by advanced laparoscopists for prediction of POD obliteration.


Assuntos
Escavação Retouterina/diagnóstico por imagem , Escavação Retouterina/patologia , Laparoscopia , Doenças Peritoneais/diagnóstico , Gravação em Vídeo , Feminino , Humanos , Variações Dependentes do Observador , Doenças Peritoneais/diagnóstico por imagem , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Estudos Retrospectivos , Ultrassonografia
16.
Sensors (Basel) ; 19(22)2019 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-31717626

RESUMO

In this investigation, a wireless sensor network using a non-orthogonal multiple access (NOMA) system is considered in two scenarios related to the number of serving access point/base stations, where two policies provide system performance improvement in two sensors (the near user and the far user). To improve performance efficiency, two robust transmit antenna strategies are designed related to the access point/base station (BS), namely (i) Transmit Antenna Selection (TAS) mode and (ii) two base station (TBS) approach to simultaneously serve NOMA users. First, the TAS scheme is implemented to provide suboptimal outage performance for such NOMA, in which BS equipped at least two antennas while NOMA users are equippeda single antenna. Secondly, the TBS scheme is conducted to enhance the outage performance, especially considering priority evaluation for the far user in user pairs. As an important result, such far users in two proposed schemes are studied by introducing the exact closed-form expression to examine outage behavior. Accordingly, the closed-form expressions regarding ergodic capacity can be further obtained. To corroborate the exactness of these metrics, Monte Carlo simulation is performed. In addition, the proposed schemes exhibit various performance evaluations accompanied by different related parameters such as power allocation factors, the number of transmit antenna, and transmit signal-to-noise ratio (SNR).

17.
Sensors (Basel) ; 19(6)2019 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-30875822

RESUMO

In this paper, a cooperative non-orthogonal multiple access (NOMA) system is studied for the Internet-of-Things (IoT) in which a master node intends to serve multiple client nodes. The adaptive transmission strategy is proposed at the relay node, i.e., the relay can be half-duplex (HD) and/or full duplex (FD). In practical terms, numerous low-cost devices are deployed in such IoT systems and it exhibits degraded performance due to hardware imperfections. In particular, the effects of hardware impairments in the NOMA users are investigated. Specifically, the closed-form expressions are derived for the outage probability. Moreover, the ergodic capacity is also analysed. This study also comparatively analyzes the orthogonal multiple access (OMA) and NOMA with HD and/or FD relaying. The numerical results are corroborated through Monte Carlo simulations.

18.
Sensors (Basel) ; 19(15)2019 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-31357691

RESUMO

In this paper, we investigate the performance of a secondary network in a cognitive radio network employing a non-orthogonal multiple access (NOMA) scheme to form a CR-NOMA system serving many destination users. In the secondary network of our proposed system, a device-to-device (D2D) scheme is deployed to further provide the signal transmission at a close distance of NOMA users in downlink, and such performance is evaluated under the situation of interference reception from the primary network. An outage performance gap exists among these NOMA users since different power allocation factors are assigned to the different destinations. Unlike existing NOMA schemes that consider fixed power allocation factors, which are not optimal in terms of outage performance, our proposed paradigm exhibits optimal outage in the scenario of D2D transmission. In particular, the outage performances in two kinds of schemes in term of existence of D2D link are further achieved. Simulation results validate the analytical expressions, and show the advantage of each scheme in the proposed CR-NOMA system based on outage performance and throughput.

19.
Molecules ; 24(18)2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31514275

RESUMO

This paper deals with the development and characteristics of the properties of a permeable water-resistant heat insulation panel based on recycled materials. The insulation panel consists of a thermal insulation core of recycled soft polyurethane foam and winter wheat husk, a layer of geopolymer that gives the entire sandwich composite strength and fire resistance, and a nanofibrous membrane that permits water vapor permeability, but not water in liquid form. The observed properties are the thermal conductivity coefficient, volumetric heat capacity, fire resistance, resistance to long-term exposure of a water column, and the tensile strength perpendicular to the plane of the board. The results showed that while the addition of husk to the thermal insulation core does not significantly impair its thermal insulation properties, the tensile strength perpendicular to the plane of these boards was impaired by the addition of husk. The geopolymer layer increased the fire resistance of the panel for up to 13 min, and the implementation of the nanofibrous membrane resulted in a water flow of 154 cm2 in the amount of 486 g of water per 24 h at a water column height of 0.8 m.


Assuntos
Temperatura Alta , Fenômenos Mecânicos , Reciclagem , Água/química , Membranas Artificiais , Nanofibras/química , Permeabilidade , Poliuretanos/química , Condutividade Térmica , Triticum/química
20.
J Cell Physiol ; 233(1): 688-698, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28328069

RESUMO

Understanding the role and underlying regulation mechanism of autophagy in lipopolysaccharide-induced lung injury (LPS-LI) may provide potentially new pharmacological targets for treatment of acute lung injury. The aim of this study was to investigate the functional significance of autophagy in LPS-LI. The autophagy of human pulmonary microvascular endothelial cells (HPMVECs) and mice was inhibited before they were challenged with LPS. In vitro, permeability, vitality, and the LDH release rate of the cells were detected, the zonula occluden-1 (ZO-1) expression and the stress fiber formation were determined. In vivo, the lung injury was assessed. We found LPS caused high permeability and increased lactate dehydrogenase (LDH) release rate, lowered viability of the cells, inhibited the ZO-1 expression and induced stress fiber formation, these effects were further aggravated by prohibiting the level of autophagy. Consistently, in in vivo experiments, LPS-induced serious lung injury, which was reflected as edema, leukocyte infiltration and hemorrhage in lung tissue, and the high concentration of pro-inflammation cytokines tumor necrosis factor (TNF)-α and interleukin (IL)-1ß in bronchoalveolar lavage fluid (BALF). Inhibiting autophagy further exacerbated LPS-LI. It appears that autophagy played a protective role in LPS-LI in part through restricting the injury of lung microvascular barrier.


Assuntos
Lesão Pulmonar Aguda/metabolismo , Autofagia , Barreira Alveolocapilar/metabolismo , Permeabilidade Capilar , Células Endoteliais/metabolismo , Lipopolissacarídeos , Pulmão/irrigação sanguínea , Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/genética , Lesão Pulmonar Aguda/patologia , Animais , Proteína 5 Relacionada à Autofagia/genética , Proteína 5 Relacionada à Autofagia/metabolismo , Proteína 7 Relacionada à Autofagia/genética , Proteína 7 Relacionada à Autofagia/metabolismo , Barreira Alveolocapilar/ultraestrutura , Células Cultivadas , Modelos Animais de Doenças , Células Endoteliais/ultraestrutura , Humanos , Pulmão/metabolismo , Pulmão/ultraestrutura , Camundongos Endogâmicos C57BL , Edema Pulmonar/induzido quimicamente , Edema Pulmonar/metabolismo , Edema Pulmonar/patologia , Interferência de RNA , Fibras de Estresse/metabolismo , Transfecção , Proteína da Zônula de Oclusão-1/metabolismo
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