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1.
Sensors (Basel) ; 23(10)2023 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-37430613

RESUMO

Virtualization is a core 5G network technology which helps telecom companies significantly reduce capital expenditure and operating expenses by deploying multiple services on the same hardware infrastructure. However, providing QoS-guaranteed services for multi-tenants poses a significant challenge due to multi-tenant service diversity. Network slicing has been proposed as a means of addressing this problem by isolating computing and communication resources for the different tenants of different services. However, optimizing the allocation of the network and computation resources across multiple network slices is a critical but extremely difficult problem. Accordingly, this study proposes two heuristic algorithms, namely Minimum Cost Resource Allocation (MCRA) and Fast Latency Decrease Resource Allocation (FLDRA), to perform dynamic path routing and resource allocation for multi-tenant network slices in a two-tier architecture. The simulation results show that both algorithms significantly outperform the Upper-tier First with Latency-bounded Overprovisioning Prevention (UFLOP) algorithm proposed in previous work. Furthermore, the MCRA algorithm achieves a higher resource utilization than the FLDRA algorithm.

2.
Sensors (Basel) ; 23(2)2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36679651

RESUMO

Deep learning technology has developed rapidly in recent years and has been successfully applied in many fields, including face recognition. Face recognition is used in many scenarios nowadays, including security control systems, access control management, health and safety management, employee attendance monitoring, automatic border control, and face scan payment. However, deep learning models are vulnerable to adversarial attacks conducted by perturbing probe images to generate adversarial examples, or using adversarial patches to generate well-designed perturbations in specific regions of the image. Most previous studies on adversarial attacks assume that the attacker hacks into the system and knows the architecture and parameters behind the deep learning model. In other words, the attacked model is a white box. However, this scenario is unrepresentative of most real-world adversarial attacks. Consequently, the present study assumes the face recognition system to be a black box, over which the attacker has no control. A Generative Adversarial Network method is proposed for generating adversarial patches to carry out dodging and impersonation attacks on the targeted face recognition system. The experimental results show that the proposed method yields a higher attack success rate than previous works.


Assuntos
Aprendizado Profundo , Reconhecimento Facial , Redes Neurais de Computação
3.
West J Emerg Med ; 23(2): 258-267, 2022 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-35302462

RESUMO

BACKGROUND: Early recognition and prevention of in-hospital cardiac arrest (IHCA) have played an increasingly important role in the chain of survival. However, clinical tools for predicting IHCA are scarce, particularly in the emergency department (ED). We sought to estimate the incidence of ED-based IHCA and to develop and validate a novel triage tool, the Emergency Department In-hospital Cardiac Arrest Score (EDICAS), for predicting ED-based IHCA. METHODS: In this retrospective cohort study we used electronic clinical warehouse data from a tertiary medical center with approximately 100,000 ED visits per year. We extracted data from 733,398 ED visits over a seven-year period. We selected one ED visit per person and excluded out-of-hospital cardiac arrest or children. Patient demographics and computerized triage information were included as potential predictors. RESULTS: A total of 325,502 adult ED patients were included. Of these patients, 623 (0.2%) developed ED-based IHCA. The EDICAS, which includes age and arrival mode and categorizes vital signs with simple cut-offs, showed excellent discrimination (area under the receiver operating characteristic [AUROC] curve, 0.87) and maintained its discriminatory ability (AUROC, 0.86) in cross-validation. Previously developed early warning scores showed lower AUROC (0.77 for the Modified Early Warning Score and 0.83 for the National Early Warning Score) when applied to our ED population. CONCLUSION: In-hospital cardiac arrest in the ED is relatively uncommon. We developed and internally validated a novel tool for predicting imminent IHCA in the ED. Future studies are warranted to determine whether this tool could gain lead time to identify high-risk patients and potentially reduce ED-based IHCA.


Assuntos
Parada Cardíaca , Triagem , Adulto , Área Sob a Curva , Criança , Serviço Hospitalar de Emergência , Parada Cardíaca/diagnóstico , Parada Cardíaca/epidemiologia , Parada Cardíaca/etiologia , Humanos , Estudos Retrospectivos
4.
BMC Bioinformatics ; 22(1): 305, 2021 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-34090341

RESUMO

BACKGROUND: Early detection of bladder cancer remains challenging because patients with early-stage bladder cancer usually have no incentive to take cytology or cystoscopy tests if they are asymptomatic. Our goal is to find non-invasive marker candidates that may help us gain insight into the metabolism of early-stage bladder cancer and be examined in routine health checks. RESULTS: We acquired urine samples from 124 patients diagnosed with early-stage bladder cancer or hernia (63 cancer patients and 61 controls). In which 100 samples were included in our marker discovery cohort, and the remaining 24 samples were included in our independent test cohort. We obtained metabolic profiles of 922 compounds of the samples by gas chromatography-mass spectrometry. Based on the metabolic profiles of the marker discovery cohort, we selected marker candidates using Wilcoxon rank-sum test with Bonferroni correction and leave-one-out cross-validation; we further excluded compounds detected in less than 60% of the bladder cancer samples. We finally selected eight putative markers. The abundance of all the eight markers in bladder cancer samples was high but extremely low in hernia samples. Moreover, the up-regulation of these markers might be in association with sugars and polyols metabolism. CONCLUSIONS: In the present study, comparative urine metabolomics selected putative metabolite markers for the detection of early-stage bladder cancer. The suggested relations between early-stage bladder cancer and sugars and polyols metabolism may create opportunities for improving the detection of bladder cancer.


Assuntos
Neoplasias da Bexiga Urinária , Biomarcadores Tumorais , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Metaboloma , Metabolômica , Neoplasias da Bexiga Urinária/diagnóstico
5.
Eur J Emerg Med ; 28(5): 394-401, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34191766

RESUMO

BACKGROUND AND IMPORTANCE: Although factors related to a return emergency department (ED) visit have been reported, few studies have examined 'high-risk' return ED visits with serious adverse outcomes. Understanding factors associated with high-risk return ED visits may help with early recognition and prevention of these catastrophic events. OBJECTIVES: We aimed to (1) estimate the incidence of high-risk return ED visits, and (2) to investigate time-varying factors associated with these revisits. DESIGN: Case-crossover study. SETTINGS AND PARTICIPANTS: We used electronic clinical warehouse data from a tertiary medical center. We retrieved data from 651 815 ED visits over a 6-year period. Patient demographics and computerized triage information were extracted. OUTCOME MEASURE AND ANALYSIS: A high-risk return ED visit was defined as a revisit within 72 h of the index visit with ICU admission, receiving emergency surgery, or with in-hospital cardiac arrest during the return ED visit. Time-varying factors associated with a return visit were identified. MAIN RESULTS: There were 440 281 adult index visits, of which 19 675 (4.5%) return visits occurred within 72 h. Of them, 417 (0.1%) were high-risk revisits. Multivariable analysis showed that time-varying factors associated with an increased risk of high-risk revisits included the following: arrival by ambulance, dyspnea, or chest pain on ED presentation, triage level 1 or 2, acute change in levels of consciousness, tachycardia (>90/min), and high fever (>39°C). CONCLUSIONS: We found a relatively small fraction of discharges (0.1%) developed serious adverse events during the return ED visits. We identified symptom-based and vital sign-based warning signs that may be used for patient self-monitoring at home, as well as new-onset signs during the return visit to alert healthcare providers for timely management of these high-risk revisits.


Assuntos
Serviço Hospitalar de Emergência , Readmissão do Paciente , Adulto , Dor no Peito , Estudos Cross-Over , Humanos , Triagem
6.
J Clin Hypertens (Greenwich) ; 23(3): 628-637, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33336887

RESUMO

Home blood pressure (BP) monitoring is a useful tool for hypertension management. BP variability (BPV) has been associated with an increased risk of cardiovascular events. However, little is known about the correlation between BPV and different measurement patterns of long-term home BP monitoring. This longitudinal cohort study aimed to assess the associations between dynamic BP measurement patterns and BPV. A total of 1128 participants (mean age, 77.4 ± 9.3 years; male, 51%) with 23 269 behavior measuring units were included. We used sliding window sampling to classify the home BP data with a regular 6-month interval into units in a sliding manner until the data are not continuous. Three measurement patterns (stable frequent [SF], stable infrequent [SI], and unstable [US]) were assessed based on the home BP data obtained within the first 3 months of the study, and the data in the subsequent 3 months were used to assess the BPV of that unit. We used linear mixed-effects model to assess the association between BP measurement patterns and BPV with adjustment for possible confounding factors including average BP. Average real variability and coefficient variability were used as measures of the BPV. No significant differences were observed in average BP between the SF, SI, and US patterns. However, BPV in the SF group was significantly lower than that in the US and SI groups (all p-values < .05). The BPV in SI and US groups was not significantly different. A stable and frequent BP measuring pattern was independently associated with a lower BPV.


Assuntos
Hipertensão , Idoso , Idoso de 80 Anos ou mais , Pressão Sanguínea , Determinação da Pressão Arterial , Monitorização Ambulatorial da Pressão Arterial , Humanos , Hipertensão/diagnóstico , Hipertensão/epidemiologia , Estudos Longitudinais , Masculino
7.
Oncotarget ; 8(24): 38802-38810, 2017 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-28415579

RESUMO

Bladder cancer is one of the most common urinary tract carcinomas in the world. Urine metabolomics is a promising approach for bladder cancer detection and marker discovery since urine is in direct contact with bladder epithelia cells; metabolites released from bladder cancer cells may be enriched in urine samples. In this study, we applied ultra-performance liquid chromatography time-of-flight mass spectrometry to profile metabolite profiles of 87 samples from bladder cancer patients and 65 samples from hernia patients. An OPLS-DA classification revealed that bladder cancer samples can be discriminated from hernia samples based on the profiles. A marker discovery pipeline selected six putative markers from the metabolomic profiles. An LLE clustering demonstrated the discriminative power of the chosen marker candidates. Two of the six markers were identified as imidazoleacetic acid whose relation to bladder cancer has certain degree of supporting evidence. A machine learning model, decision trees, was built based on the metabolomic profiles and the six marker candidates. The decision tree obtained an accuracy of 76.60%, a sensitivity of 71.88%, and a specificity of 86.67% from an independent test.


Assuntos
Biomarcadores Tumorais/análise , Metaboloma , Metabolômica/métodos , Neoplasias da Bexiga Urinária/diagnóstico , Idoso , Estudos de Casos e Controles , Cromatografia Líquida , Feminino , Seguimentos , Humanos , Masculino , Espectrometria de Massas , Pessoa de Meia-Idade , Prognóstico , Neoplasias da Bexiga Urinária/metabolismo
8.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 27(4): 491-5, 2005 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-16178446

RESUMO

OBJECTIVE: To explore the role of monocyte chemoattractant protein-1 (MCP-1) in lupus nephritis (LN). METHODS: Sera MCP-1 levels were measured by enzyme linked immunosorbent assay in 112 patients with systemic lupus erythematosus (SLE), 30 patients with rheumatoid arthritis, 11 non-SLE patients with renal impairment, and 40 healthy volunteers. MCP-1 mRNA expression in peripheral blood mononuclear cells (PBMCs) was also investigated with reverse trancription-polymerase chain reaction semi-quantitative method. RESULTS: The expression of MCP-1 was significantly higher in active LN groups than in all other groups (P < 0.001), and there was a close correlation between MCP-1 expression and the overall SLE disease activity index score (r=0.6245, P < 0.001) and the SLE disease activity index renal score (r=0.6808, P < 0.001). Low expression of MCP-1 was observed in diseased controls and healthy controls. The sera levels of MCP-1 were significantly higher in patients with active diseases than in patients with inactive SLE and controls, but no significant difference were found between the active LN groups and non-renal involvement group (P >0.05). CONCLUSION: The expression of PBMCs MCP-1 mRNA is upregulated in active SLE. Meanwhile, its expression levels are correlated with the activity of LN.


Assuntos
Quimiocina CCL2/biossíntese , Lúpus Eritematoso Sistêmico/metabolismo , Nefrite Lúpica/metabolismo , Adolescente , Adulto , Idoso , Artrite Reumatoide/metabolismo , Quimiocina CCL2/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/biossíntese , RNA Mensageiro/genética
9.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 26(3): 298-301, 2004 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-15266834

RESUMO

OBJECTIVE: To explore the role of eotaxin in the pathogenesis of bronchial asthma and the clinical value in the diagnosis of asthma. METHODS: Serum eotaxin were measured by ELISA in 38 patients with asthma, 28 patients with non-asthma allergy, and 30 healthy controls. RESULTS: The levels of serum eotaxin in the asthma group were higher than those in the non-asthma allergic and control group (P<0.01). Furthermore, eotaxin levels in patients with acute asthma were significantly higher than those in patients with stable asthma (P<0.001). It was also found that the eotaxin levels of the acute asthma group were positively correlated to the amounts of eosinophils in peripheral blood (r=0.4196, P<0.001), and inversely correlated to the forced expiratory volume in one second (FEV1) (r=-0.3746, P<0.001). CONCLUSION: It suggests that eotaxin may play a crucial pathogenic role in the asthmatic process possibly by activating the allergic inflammatory cells and controlling the recruitment of eosinophils from blood to bronchial epithelium of the airway. The concentration of eotaxin is significantly associated with the attack of acute asthma and its severity. Eotaxin may be a potential therapeutic target in patients with asthma.


Assuntos
Asma/diagnóstico , Quimiocinas CC/sangue , Adulto , Asma/fisiopatologia , Contagem de Células , Quimiocina CCL11 , Quimiocinas CC/fisiologia , Eosinofilia/patologia , Feminino , Volume Expiratório Forçado , Humanos , Masculino , Pessoa de Meia-Idade
10.
Zhongguo Zhong Yao Za Zhi ; 29(6): 570-5, 2004 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-15706927

RESUMO

OBJECTIVE: To observe inhibiting effect of CGE (compound ginseng extract) on increased expression of IL-1beta and c-fos protein following cerebral ischemia-reperfusion. METHOD: The vascular dementia model was made by middle cerebral artery occlusion for 2 hours. Expression of IL-1beta and c-fos were determined by immunohistochemistry in the hippocampus regions in brain tissue at the 0.5 h-7 d after reperfusion. CGE was diluted by CMC and poured into the stomach by 0.7 mL x (100 g)(-1) with a high dosage (19.34 x 10(3) g x L(-1) row herbs), a middle dosage (9.67 x 10(3) g x L(-1)), a low dosage (4.83 x 10(3) g x L(-1)). There were an IL-1ra (rhIL-1ra 20 microg injected into the left cerebral ventricle), a sham operation (NaCl 20 microL injected into the left cerebral ventricle) and a model as control. RESULT: Compared with control group, three dose groups (low, middle and high) in CGE showed significant inhibiting effects on the expression of c-fos protein at 2, 3, 4, 12 hours and 3 day following cerebral ischaemic-reperfusion. The level of the inhibiting effects in small and middle groups were lower at all time points than that in IL-1ra group (P < 0.05 to P < 0.01). CGE inhibited the expression of hippocampus IL-1beta protein, taking effect from the 2 h after reperfusion. Both HD group (531 +/- 151.1) and MD group (589.3 +/- 78.6) showed more obvious effect which lasted until the 72 h compared with the model group (687.6 +/- 116.7) (P < 0.01 and 0.05). Large dose group (81.3 +/- 16.1) showed the same level of the inhibiting effect on expression of c-fos protein as IL-1ra group (67.2 +/- 25.7) from 4 hour on following cerebral ischaemic reperfusion (P > 0.05). CONCLUSION: CGE with function of Yiqi Bushen, Huoxue Huatan has effect of inhibiting up-regulated expression of IL-1beta and c-fos protein following cerebral ischemia-reperfusion. However, this effect of CGE starts relatively later than that of IL-1ra. The effect of CGE is associated with its dosage, i.e. a larger dosage has a better effect on expression of c-fos protein in post-stroke dementia.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Hipocampo/metabolismo , Interleucina-1/metabolismo , Proteínas Proto-Oncogênicas c-fos/metabolismo , Traumatismo por Reperfusão/metabolismo , Animais , Isquemia Encefálica/complicações , Cistanche/química , Relação Dose-Resposta a Droga , Combinação de Medicamentos , Medicamentos de Ervas Chinesas/isolamento & purificação , Masculino , Panax/química , Plantas Medicinais/química , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/etiologia
11.
Zhonghua Yi Xue Za Zhi ; 83(16): 1409-12, 2003 Aug 25.
Artigo em Chinês | MEDLINE | ID: mdl-14521744

RESUMO

OBJECTIVE: To study the influence of beta-endorphin (beta end) on the function of immune system of patients with cerebral hemorrhage at different stages. METHODS: Radioimmunal analysis was applied to detect the serum beta-endorphin concentration in the peripheral blood of 28 patients with cerebral hemorrhage, aged 65.5 +/- 13, 28 age-matched patients with cerebral thrombosis, and 28 sex and age-matched normal controls. Mononuclear cells from peripheral blood of these 3 kinds of subjects were cultured and then beta end 10(-8) g/L, beta end 10(-11) g/L, beta end 10(-14) g/L, or beta end 10(-11) g/L + naloxone 10(-5) g/L were added into the media respectively and the MNCs were cultured for more 24 hours (beta end 10(-8) g/L group, beta end 10(-11) g/L group, beta end 10(-14) g/L group, and beta end 10(-11) g/L + Nal group). Another MNCs were cultured without addition of beta end (beta end 0 g/L group). Then the MNCs were collected. RT-PCR was used to detect the expressions of interleukin (IL)-1beta, IL-2, IL-8 and iNOS mRNA in the MNCs. RESULTS: The serum beta-end level of the patients with cerebral hemorrhage at the acute stage was 129 +/- 82 ng/L, significantly lower than that of the normal controls (321 +/- 62 ng/L, P<0.01) and that of the patients with cerebral thrombosis (264 +/- 163 ng/L, P<0.05), but not significantly different from that of the patients with cerebral hemorrhage in the convalescent stage (160 +/- 72 ng/L, P>0.05). The expression of IL-1beta and the expression of IL-2 of the patients with cerebral hemorrhage at the acute stage were significantly lower than those of the patients with cerebral thrombosis and the controls (all P<0.01). The expression of IL-1beta of the patients with cerebral hemorrhage at the convalescent stage were higher than that in the acute stage, however, the difference was not significant (P>0.05). The expression of IL-2 of the patients with cerebral hemorrhage at the convalescent stage was higher than that at the acute stage (P<0.01). The expression of IL-8 and the expression of iNOS of the patients with cerebral hemorrhage at the acute stage were significantly higher than those of the patients of cerebral thrombosis and the controls (both P<0.01). The expression of IL-8 and the expression of iNOS of the patients with cerebral hemorrhage at the convalescent stage were significantly lower than those in the acute stage (both P<0.01). The expressions of IL-1beta, IL-2, IL-8, and iNOS mRNA in the peripheral blood MNCs in vitro in the beta end 10(-8) g/L group and beta end 10(-11) g/L group were significantly higher than those of the beta end 0 g/L group, beta end 10(-11) g/L group, and beta-end 10(-11) g/L + Nal 10(-5)g/L group. The expressions of IL-1beta, IL-2, IL-8, and iNOS mRNA in the peripheral blood MNCs in the beta-end 10(-11) g/L +Nal 10(-5) g/L group were higher than those of the beta end 0 g/L group, however, not significantly. CONCLUSIONS: The endogenous beta-endorphin level of cerebral hemorrhage patients is low. The immune system function is up-regulated at the acute stage and then down-regulated. Thereafter the immune system function is invariably low. Exogenous beta-endorphin enhances the IL-1 beta, IL-2, IL-8 and iNOS mRNA expression of peripheral blood MNCS. beta-endorphin receptor antagonist naloxone blocks the positive immunoregulation by beta-endorphin.


Assuntos
Hemorragia Cerebral/imunologia , Sistema Imunitário/efeitos dos fármacos , beta-Endorfina/farmacologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Sistema Imunitário/fisiologia , Interleucina-8/genética , Masculino , Pessoa de Meia-Idade , Naloxona/farmacologia , Óxido Nítrico Sintase/genética , Óxido Nítrico Sintase Tipo II , RNA Mensageiro/análise
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