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1.
Biomed Res Int ; 2020: 2148706, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33145342

RESUMO

Background: Endotoxin-associated acute kidney injury (AKI), a disease characterized by marked oxidative stress and inflammation disease, is a major cause of mortality in critically ill patients. Mitochondrial fission and pyroptosis often occur in AKI. However, the underlying biological pathways involved in endotoxin AKI remain poorly understood, especially those related to mitochondrial dynamics equilibrium disregulation and pyroptosis. Previous studies suggest that heme oxygenase- (HO-) 1 confers cytoprotection against AKI during endotoxic shock, and PTEN-induced putative kinase 1 (PINK1) takes part in mitochondrial dysfunction. Thus, in this study, we examine the roles of HO-1/PINK1 in maintaining the dynamic process of mitochondrial fusion/fission to inhibit pyroptosis and mitigate acute kidney injury in rats exposed to endotoxin. Methods: An endotoxin-associated AKI model induced by lipopolysaccharide (LPS) was used in our study. Wild-type (WT) rats and PINK1 knockout (PINK1KO) rats, respectively, were divided into four groups: the control, LPS, Znpp+LPS, and Hemin+LPS groups. Rats were sacrificed 6 h after intraperitoneal injecting LPS to assess renal function, oxidative stress, and inflammation by plasma. Mitochondrial dynamics, morphology, and pyroptosis were evaluated by histological examinations. Results: In the rats with LPS-induced endotoxemia, the expression of HO-1 and PINK1 were upregulated at both mRNA and protein levels. These rats also exhibited inflammatory response, oxidative stress, mitochondrial fission, pyroptosis, and decreased renal function. After upregulating HO-1 in normal rats, pyroptosis was inhibited; mitochondrial fission and inflammatory response to oxidative stress were decreased; and the renal function was improved. The effects were reversed by adding Znpp (a type of HO-1 inhibitor). Finally, after PINK1 knockout, there is no statistical difference in the LPS-treated group and Hemin or Znpp pretreated group. Conclusions: HO-1 inhibits inflammation response and oxidative stress and regulates mitochondria fusion/fission to inhibit pyroptosis, which can alleviate endotoxin-induced AKI by PINK1.

2.
Anat Sci Educ ; 2020 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-33217164

RESUMO

The Covid-19 pandemic launched the use of online courses in Chinese medical schools during February 2020. To evaluate the state of gross anatomy education in China during the pandemic, a nationwide survey was conducted through convenience sampling by email or respondent invitations on social media. A total of 359 questionnaires were received from the respondents. The first response from a given school was included in the study to represent that school, thus, 77 questionnaires were used for analyses. Schools represented were from all provinces in mainland China as well as Hong Kong and Macao. The survey found that before the pandemic, 74.0% and 33.8% of the 77 schools conducted online theoretical and practical sessions, respectively, on gross anatomy, and 36 (46.8% of 77) had temporarily suspended practical sessions at the time the survey. Body donation programs were also affected with 26.0% and 27.3% of the 77 schools having suspended donation programs or saw a decreased number of donations. During the pandemic, 40.3% of the 77 schools kept or initiated the implementation of active learning, and online assessment was continued in 49.4% of the 77 medical schools. Another 26 (33.8%) schools initiated online assessment during the pandemic. A total of 359 answers were included for the analysis of the "teachers' perception of the online teaching experience". Nearly half (46.2%) of the 359 responded teachers were satisfied with the effectiveness of online teaching during the pandemic. A total of 36.2% of these respondents preferred to implement online teaching of theoretical sessions after the pandemic, and 89 (24.8%) teachers were keen to return to traditional face-to-face anatomy education.

3.
Neuroscience ; 2020 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-33197504

RESUMO

Alzheimer's disease (AD) is the most common neurodegenerative disease and is characterized by progressive memory loss and cognitive dysfunction. Long non-coding RNAs (lncRNAs) have been shown to be among the most promising biomarkers and therapeutic targets of AD. Here, we aimed to investigate whether lncRNA BACE1-AS plays a role in the potential mechanisms of AD. The expression of BACE1-AS, miR-214-3p and ATG5 mRNA was detected using qRT-PCR. The expression of the LC3, P62, ATG5, Bcl-2, p-Tau and cleaved-caspase 3 proteins was examined using western blot analysis. Cell apoptosis, cytotoxicity and ROS levels were estimated using flow cytometry, an LDH kit and a DCFH-DA assay, respectively. The interaction between BACE1-AS or ATG5 and miR-214-3p was validated using a dual-luciferase reporter assay. HE staining and a TUNEL assay were employed to evaluate hippocampal neuronal injury. The BACE1-AS level was found to be upregulated in serum samples of AD patients, brain tissues of AD transgenic (Tg) mice and Aß1-42-treated SH-SY5Y cells. Autophagy activity was increased in both Tg mice and Aß1-42-treated cells. BACE1-AS knockdown alleviated Aß1-42-induced cell injury. Rapamycin abolished the protective effects of sh BACE1-AS against Aß1-42 induced cell injury. BACE1-AS indirectly regulated ATG5 expression by binding miR-214-3p. The miR-214-3p inhibitor reversed the protective effects of sh BACE1-AS and sh ATG5 against Aß1-42-induced cell injury. Knockdown of BACE1-AS alleviated neuronal injury by repressing autophagy in vivo. Our findings demonstrate that silencing of BACE1-AS alleviated neuronal injury by regulating autophagy through the miR-214-3p/ATG5 signalling axis in AD.

6.
Medicine (Baltimore) ; 99(46): e23102, 2020 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-33181675

RESUMO

BACKGROUND: Colonoscopy is considered a safe and effective tool for detecting colorectal cancer. Nevertheless, the proportion of patients are hesitating to receive colonoscopy. Smartphone education may decrease the barrier of colonoscopy. The aim of this study is to examine the effectiveness of smartphone education in colonoscopy. METHODS: We conducted a prospective, double-blinded, randomized, controlled study to examine the effectiveness of smartphone education on embarrassment, bowel preparation, and satisfaction in colonoscopy. The patients' embarrassment was measured by the colonoscopy embarrassment scale. The quality of the bowel preparation was evaluated by gastroenterologists according to the Aronchik Scale. The satisfaction of colonoscopy care was assessed by a satisfaction scale developed by the authors. RESULTS: A total of 150 patients were analyzed in the smartphone education and control groups (n = 75 in each group). The smartphone education group reported fewer embarrassment (B = -2.78, P = .02) than those of the control group, the patients who were older (B = .15, P = .001) and who were male (B = 2.91, P = .003) showed higher embarrassment. Additionally, smartphone education group were likely to have better colon preparation (odds ratio = 2.46, 95% confidence interval: 1.20-5.02) than that of the control group. Smartphone education also improved the satisfaction with care (ß = 4.60, P < .001), and above normal body mass index decreased the satisfaction with care (ß = -0.19, P < .05). CONCLUSION: Smartphone education improves embarrassment, bowel preparation, and satisfaction with care in patients receiving colonoscopy.


Assuntos
Colonoscopia/psicologia , Neoplasias Colorretais/diagnóstico , Instrução por Computador , Cooperação do Paciente/psicologia , Cuidados Pré-Operatórios , Smartphone , Colonoscopia/métodos , Instrução por Computador/instrumentação , Instrução por Computador/métodos , Método Duplo-Cego , Constrangimento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Educação de Pacientes como Assunto/métodos , Satisfação Pessoal , Cuidados Pré-Operatórios/métodos , Cuidados Pré-Operatórios/psicologia
7.
BMC Infect Dis ; 20(1): 818, 2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-33167900

RESUMO

BACKGROUND: To explore the kinetic changes in virology, specific antibody response and imaging during the clinical course of COVID-19. METHODS: This observational study enrolled 20 patients with COVID-19, who were hospitalized between January 20-April 6, 2020, in the two COVID-19 designated hospitals of Zhoushan, Zhejiang and Rushan, Shandong, China, The laboratory findings, imaging, serum response to viral infection, and viral RNA level in the throat and stool samples were assessed from onset to recovery phase in patients with COVID-19. RESULTS: SARS-COV-2 RNA was positive as early as day four. It remained positive until day 55 post-onset in the sputum-throat swabs and became negative in most cases (55%) within 14 days after onset. Lymphocytopenia occurred in 40% (8/20) of patients during the peak infection period and returned to normal at week five. The most severe inflammation in the lungs appeared in week 2 or 3 after onset, and this was completely absorbed between week 6 and 8 in 85.7% of patients. All patients had detectable antibodies to the receptor binding domain (RBD), and 95% of these patients had IgG to viral N proteins. The antibody titer peaked at week four. Anti-S IgM was positive in 7 of 20 patients after week three. CONCLUSIONS: All COVID-19 patients in this study were self-limiting and recovered well though it may take as long as 6-8 weeks. Our findings on the kinetic changes in imaging, serum response to viral infection and viral RNA level may help understand pathogenesis and define clinical course of COVID-19.


Assuntos
Anticorpos Antivirais/sangue , Betacoronavirus/imunologia , Técnicas de Laboratório Clínico , Infecções por Coronavirus/diagnóstico por imagem , Infecções por Coronavirus/imunologia , Pulmão/diagnóstico por imagem , Pneumonia Viral/diagnóstico por imagem , Pneumonia Viral/imunologia , Adolescente , Adulto , Idoso , Betacoronavirus/genética , Criança , China/epidemiologia , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/virologia , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Masculino , Pessoa de Meia-Idade , Proteínas do Nucleocapsídeo/imunologia , Pandemias , Pneumonia Viral/epidemiologia , Pneumonia Viral/virologia , RNA Viral/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Escarro/virologia , Tomografia Computadorizada por Raios X , Adulto Jovem
8.
PLoS One ; 15(11): e0240046, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33170868

RESUMO

This paper propose a direct generalization quantile regression estimation method (DGQR estimation) for quantile regression with varying-coefficient models with interval censored data, which is a direct generalization for complete observed data. The consistency and asymptotic normality properties of the estimators are obtained. The proposed method has the advantage that does not require the censoring vectors to be identically distributed. The effectiveness of the method is verified by some simulation studies and a real data example.

9.
Poult Sci ; 99(11): 6147-6162, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33142533

RESUMO

Melatonin is a key regulator of follicle granular cell maturation and ovulation. The mammalian target of rapamycin (mTOR) pathway plays an important role in cell growth regulation. Therefore, our aim was to investigate whether the mTOR signaling pathway is involved in the regulation of melatonin-mediated proliferation and apoptotic mechanisms in granulosa cells. Chicken follicle granular cells were cultured with melatonin (0, 2, 20, or 200 µmol/L) for 48 h. The results showed that melatonin treatment enhanced proliferation and suppressed apoptosis in granular cells at 20 µmol/L and 200 µmol/L (P < 0.05) by upregulation of cyclin D1 (P < 0.01) and Bcl-2 (P < 0.01) and downregulation of P21, caspase-3, Beclin1, and LC3-II (P < 0.01). The effects resulted in the activation of the mTOR signaling pathway by increasing the expression of avTOR, PKC, 4E-BP1, S6K (P < 0.05), p-mTOR, and p-S6K. We added an mTOR activator and inhibitor to the cells and identified the optimal dose (10 µmol/L MHY1485 and 100 nmol/L rapamycin) for subsequent experiments. The combination of 20 µmol/L melatonin and 10 µmol/L MHY1485 significantly enhanced granulosa cell proliferation (P < 0.05), while 100 nmol/L rapamycin significantly inhibited proliferation and enhanced apoptosis (P < 0.05), but this action was reversed in the 20-µmol/L melatonin and 100-nmol/L rapamycin cotreatment groups (P < 0.05). This was confirmed by mRNA and protein expression that was associated with proliferation, apoptosis, and autophagy (P < 0.05). The combination of 20 µmol/L melatonin and 10 µmol/L MHY1485 also activated the mTOR pathway upstream genes PI3K, AKT1, and AKT2 and downstream genes PKC, 4E-BP1, and S6K (P < 0.05), as well as protein expression of p-mTOR and p-S6K. Rapamycin significantly inhibited the mTOR pathway-related genes mRNA levels (P < 0.05). In addition, activation of the mTOR pathway increased melatonin receptor mRNA levels (P < 0.05). In conclusion, these findings demonstrate that melatonin regulates chicken granulosa cell proliferation and apoptosis by activating the mTOR signaling pathway via its receptor.

10.
Life Sci ; : 118707, 2020 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-33144187

RESUMO

Circular RNAs (circRNAs) are formed from the genome through diverse back splicing and feature the closed loop. circRNAs are widely available in a variety of cells and characterized by conservation, structural stability, high abundance and tissue-specific or developmental-specific expression. Recent studies have shown that circRNAs are closely related to liver diseases, such as metabolic-associated fatty liver disease, hepatitis, liver cirrhosis and hepatocellular carcinoma. circRNAs play an important role in the progression of liver diseases, are potential diagnostic and prognostic markers, and have translational value in therapy. This article reviews the research on circRNAs in liver diseases, with a view to providing a theoretical basis and new ideas for future research and treatment of liver diseases.

11.
Artigo em Inglês | MEDLINE | ID: mdl-33237880

RESUMO

Edge states of various two-dimensional materials such as graphene are intrinsically spin-polarized. In other materials, electric field and charge doping are required for introducing magnetism to their edges. In this work, by using first-principles calculations, we studied the effects of transverse electric field on the edge states of the armchair blue phosphorene nanoribbon (ABPNR), and found that a transverse electric field drives the edge electronic state occupied and at the same time spin-polarized. We also doped electrons to the ABPNR and found that these additional electrons occupy and spin-polarize the electronic states of both edges of the nanoribbon.

12.
Medicine (Baltimore) ; 99(45): e23151, 2020 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-33157998

RESUMO

During sepsis, platelets dysfunction contributes to organ dysfunction. Studies on platelets dysfunction in the long-term prognosis of sepsis are lacking. The aim of this study was to assess the role of platelets in the long-term prognosis of sepsis patients.A total of 4576 sepsis patients were extracted from MIMIC III Database. Survival was analyzed by the Kaplan-Meier method. Univariate and multivariate cox analyses were performed to identify prognostic factors. Significant prognostic factors were combined to build a nomogram to predict 1 year overall survival (OS). The discriminative ability and predictive accuracy of the nomogram were evaluated using the receiver operating characteristic curve (ROC) analysis and calibration curves used for sepsis.The more abnormal the platelet level, the worse prognosis of patients. After final regression analysis, age, blood urea nitrogen, platelets, international normalized ratio, partial thromboplastin time, potassium, hemoglobin, white blood cell count, organ failures were found to be independent predictors of 1 year OS of sepsis patient and were entered into a nomogram. The nomogram showed a robust discrimination, with an area under the receiver operating characteristic curve of 0.752. The calibration curves for the probability of the prognosis of sepsis patients showed optimal agreement between the probability as predicted by the nomogram and the actual probability.Platelet was an independent prognostic predictor of 1 year OS for patients with sepsis. Platelet-related nomogram that can predict the 1 year OS of sepsis patients. It revealed optimal discrimination and calibration, indicating that the nomogram may have clinical utility.


Assuntos
Plaquetas , Sepse/sangue , Sepse/mortalidade , Idoso , Estudos de Coortes , Bases de Dados Factuais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nomogramas , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida , Fatores de Tempo
13.
Food Chem Toxicol ; 146: 111815, 2020 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-33157167

RESUMO

Previous studies on the risk assessment of chemicals with respect to human health have focused mainly on the safety of individual substances. Recently, public health policy emphasizes the combined effects of mixtures. An overall risk probability (ORP)-based method long with the combined toxicity factor (cuv) can be used to evaluate the combined toxicity of chemical mixtures from the environment and foods on human health. However, the procedure for calculating the cuv accurately and quantitatively in the ORP method is yet unclear. In this study, an improved ORP-based method (IORP) was developed by introducing a variable time t, and the cuv was analyzed quantitatively using simultaneous equations and based on the principle of least squares regression. This phenomenon can be explained based on the example of the mixture of aflatoxin B1 (AFB1) and microcystin LR (MC-LR) by dietary intake in order to understand the application of this method. The IORP approach makes it possible for estimating the combined effects of mixtures for human health by dietary pathway.

14.
Artigo em Inglês | MEDLINE | ID: mdl-33231418

RESUMO

Planar heterojunction (PHJ) organic photodetectors are potentially more stable than traditional bulk heterojunction counterparts because of the absence of uncontrolled phase separation in the donor and acceptor binary blend system. This work reports a new class of PHJ organic photodetectors based on the medium-band gap fullerene C60 and low-band gap fused-ring non-fullerene acceptor ID-MeIC bilayer structure, which allows a wide range of spectral response tuning across the UV-visible-near-infrared (UV-vis-NIR) region by tailoring individual layer thickness. The C60 layer not only increases the external quantum efficiency at 745 nm by 57% but also reduces dark currents by two orders of magnitude. More importantly, the p-type poly[N,N'-bis(4-butylphenyl)-N,N'-bis(phenyl)-benzi] is found to be the key compound to conduct the layer-by-layer fabrication as combined with n-type ID-MeIC for higher charge extraction efficiency. In light of the above information, PHJ organic photodetectors exhibited a specific detectivity of 6.5 × 1010 Jones to detect NIR light at 745 nm under -0.1 V. The linear dynamic range was estimated to be 80 dB. This work has demonstrated a feasible approach to develop a PHJ architecture with tunable spectral response in the UV-vis-NIR range toward long-term stable organic photodetectors for potential applications in flexible and wearable biomedical sensors.

15.
Urology ; 2020 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-33221418

RESUMO

Inflammatory myofibroblastic tumor (IMT) is a rare tumor with an indolent course. It is less often reported as a second tumor that occurs after treatment of malignant tumors in pediatric patients. Here we report a case of IMT following Wilms tumor (WT), and conduct a literature review concerning IMTs and WT to evaluate the diagnostic possibility of IMT as a second tumor. The co-existence of the two tumors may cause confusion as to whether they share genetic links or that IMTs may appear as late effects of the treatment of WT.

16.
Stem Cell Res Ther ; 11(1): 478, 2020 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-33176866

RESUMO

BACKGROUND: Our previous studies demonstrated that adipose-derived mesenchymal stromal cells (ASCs) have immunomodulatory effects that prolong allograft survival in a rodent hind-limb allotransplant model. In this study, we investigated whether the effects of immunomodulation by ASCs on allograft survival are correlated with B cell regulation. METHODS: B cells isolated from splenocytes were cocultured with ASCs harvested from adipose tissue from rodent groin areas for in vitro experiments. In an in vivo study, hind-limb allotransplantation from Brown-Norway to Lewis rats was performed, and rats were treated with ASCs combined with short-term treatment with anti-lymphocyte serum (ALS)/cyclosporine (CsA) as immunosuppressants. Peripheral blood and transplanted tissue were collected for further analysis. RESULT: An in vitro study revealed that ASCs significantly suppressed lipopolysaccharide-activated B cell proliferation and increased the percentage of Bregs. The levels of immunoregulatory cytokines, such as TGF-ß1 and IL-10, were significantly increased in supernatants of stimulated B cells cocultured with ASCs. The in vivo study showed that treatment with ASCs combined with short-term ALS/CsA significantly reduced the B cell population in alloskin tissue, increased the proportion of circulating CD45Ra+/Foxp3+ B cells, and decreased C4d expression in alloskin. CONCLUSION: ASCs combined with short-term immunosuppressant treatment prolong allograft survival and are correlated with B cell regulation, C4d expression and the modulation of immunoregulatory cytokines.

17.
Med Sci Monit ; 26: e926323, 2020 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-33206632

RESUMO

BACKGROUND Previous studies have implicated reduced brain-derived neurotrophic factor (BDNF) expression and BDNF-TrkB receptor signaling as well as microglial activation and neuroinflammation in poststroke depression (PSD). However, the contributions of microglial BDNF-TrkB signaling to PSD pathogenesis are unclear. MATERIAL AND METHODS We compared depression-like behaviors as well as neuronal and microglial BDNF and TrkB expression levels in the amygdala, a critical mood-relating limbic structure, in rat models of stroke, depression, and PSD. Depression-like behaviors were assessed using the sucrose preference test, open-field test, and weight measurements, while immunofluorescence double staining was employed to estimate BDNF and TrkB expression by CD11b-positive amygdala microglia and NeuN-positive amygdala neuron. Another group of PSD model rats were examined following daily intracerebroventricular injection of proBDNF, tissue plasminogen activator (t-PA), or normal saline (NS) for 7 days starting 4 weeks after chronic unpredictable mild stress (CUMS). RESULTS The numbers of BDNF/CD11b- and TrkB/CD11b-immunofluorescence-positive cells were lowest in the PSD group at 4 and 8 weeks after CUMS (P0.05). Injection of t-PA increased BDNF/CD11b- and TrkB/CD11b-positive cells in the amygdala of PSD rats and normalized behavior compared with NS or proBDNF injection (P<0.05). In contrast, proBDNF injection reduced BDNF and TrkB expression compared with NS (P<0.05). CONCLUSIONS These results suggest that decreased BDNF and TrkB expression by amygdala microglia may contribute to PSD pathogenesis and depression-like behaviors.

18.
Clin Imaging ; 72: 11-18, 2020 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-33197711

RESUMO

OBJECTIVE: To evaluate the diagnostic performance of magnetic resonance hysterosalpingography for fallopian tubal occlusion in the context of female infertility when compared to the diagnostic performance of conditional X-ray hysterosalpingography. METHODS: PubMed, EMBASE, Web of Science, EBSCO, Cochrane Library database, Scopus were searched for studies in which magnetic resonance hysterosalpingography and X-ray hysterosalpingography were used as diagnostic tools for tubal occlusion assessment; databases were searched through April 2020. Two researchers conducted study inclusion assessment, data extraction, a systematic review, and pooled meta-analysis independently. Stata 15.1 software was used to analyze the pooled sensitivity, specificity, diagnostic odds ratio, positive and negative likelihood ratios, and the area under the summary receiver-operating characteristic curve of magnetic resonance hysterosalpingography. RESULTS: A total of five studies involving 101 patients and 198 fallopian tubes were finally included. Compared with the conditional X-ray hysterosalpingography (the imaging gold standard), the pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio and the area under the curve of magnetic resonance hysterosalpingography for tubal occlusion were 0.91 (95% CI: 0.48-0.99), 1.00 (95% CI: 0.87-1.00), 230.47 (95% CI: 6.79-7824.72), 0.09 (95% CI: 0.01-0.80), 2676.10 (95% CI: 61.35-120,000), and 1.00 (95% CI: 0.99-1.00), respectively. Subgroup analyses revealed that viscosity of contrast agent (P = 0.024) and test order (P = 0.036) affected the accuracy of MR-HSG to evaluate tubal occlusion. CONCLUSIONS: Our meta-analysis indicated magnetic resonance hysterosalpingography may serve as an alternative for further evaluation of fallopian tubal occlusion of female infertility.

19.
JAMA Pediatr ; 2020 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-33165599

RESUMO

Importance: Escherichia coli is a leading cause of serious infection among term and preterm newborn infants. Surveillance of antibiotic susceptibility patterns of E coli among infants admitted to neonatal intensive care units should inform empirical antibiotic administration. Objective: To assess the epidemiologic characteristics and antibiotic susceptibility patterns of E coli in infants admitted to neonatal intensive care units in the US over time. Design, Setting, and Participants: This retrospective cohort study used the Premier Health Database, a comprehensive administrative database of inpatient encounters from academic and community hospitals across the US. Participants included newborn infants admitted to centers contributing microbiology data from January 1, 2009, to December 31, 2017, with E coli isolated from blood, cerebrospinal fluid, or urine cultures. Data were collected and analyzed from December 1, 2018, to November 30, 2019. Main Outcomes and Measures: Changes in annual antibiotic susceptibility of E coli during the study period. The proportion of infants with nonsusceptible organisms (resistant or intermediate susceptibility) in antibiotic categories by year, birth weight, infection source, and timing of infection and patient and center characteristics associated with neonatal E coli infection and antibiotic susceptibility were assessed. Results: A total of 721 infants (434 male [60.2%]; median age at E coli infection, 14 days [interquartile range, 1-33 days]) from 69 centers had at least 1 episode of E coli infection and available susceptibility results. No significant changes were observed over time in the overall annual proportions of antibiotic nonsusceptibility to ampicillin (mean [SD], 66.8% [1.5%]; range, 63.3% to 68.6%; estimated yearly change, -0.28% [95% CI, -1.75% to 1.18%]), nonsusceptibility to aminoglycosides (mean [SD], 16.8% [4.5%]; range, 10.7% to 23.2%; estimated yearly change, -0.85% [95% CI, -1.93% to 0.23%]), or extended-spectrum ß-lactamase phenotype (mean [SD], 5.0% [3.7%]; range, 0% to 11.1%; estimated yearly change, 0.46% [95% CI, -0.18% to 1.11%]). No isolates with nonsusceptibility to carbapenems were identified. Among 218 infants with early-onset infection, 22 (10.1%) had isolates with nonsusceptibility to both ampicillin and gentamicin, the antibiotics most commonly administered to newborns as empirical therapy. Conclusions and Relevance: In this cohort study, nonsusceptibility to commonly administered antibiotics was found in substantial proportions of neonatal E coli isolates, with no significant change from 2009 to 2017. These findings may inform empirical antibiotic choices for newborn infants.

20.
Sensors (Basel) ; 20(22)2020 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-33202665

RESUMO

An enhanced long-range navigation (eLoran) system was selected as the backup of Global Navigation Satellite Systems (GNSS), and experts and scholars are committed to improving the accuracy of the eLoran system such that its accuracy is close to the GNSS system. A differential method called eLoran differential timing technology is applied to the eLoran system, which has been used in maritime applications of eLoran. In this study, an application of eLoran differential timing technology in a terrestrial medium is carried out. Based on the eLoran timing service error, the correlation of the timing service error is analyzed in theory quantitatively to obtain the range of the difference station in the ground. The results show that to satisfy the timing accuracy of 100 ns, the action range of eLoran difference station on the land needs to be less than 55 km. Therefore, the eLoran differential method is proposed, and in the difference station, the theoretical calculation is combined with the measurement of the signal delay to obtain the difference information, which is sent to the users to adjust the prediction delay and improve the eLoran timing precision. The experiment was carried out in the Guan Zhong Plain, and the timing error of the user decreased from 394.7287 ns (pre-difference) to 19.5890 ns (post-difference). The proposed method is found to effectively enhance the timing precision of the eLoran system within the scope of action.

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