A two-step method for paroxysmal atrial fibrillation event detection based on machine learning.

Detection of atrial fibrillation (AF) events is significant for early clinical diagnosis and appropriate intervention. However, in existing detection algorithms for paroxysmal AF (AFp), the location of AF starting and ending points in AFp is not concerned. To achieve an accurate identification of AFp events in the long-term dynamic electrocardiograms (ECGs), this paper proposes a two-step method based on machine learning. In the first step, based on features extracted from the calculated R-to-R intervals (RR intervals, the cycle of heart beat), the rhythm type of the ECG signal is first classified into three classes (AFp rhythm, persistent AF (AFf) rhythm, and non-atrial fibrillation (non-AF, N) rhythm) using support vector machine (SVM). In the second step, the starting and ending points for AF episodes of AFp rhythms predicted in the first step are further located based on heartbeat classification. By training a deep convolutional neural network with phased training, the segmented beats of AFp rhythms are divided into AF beats and non-AF beats to determine the beginning and end of any AF episode. The proposed two-step method is trained and tested on the 4th China Physiological Signal Challenge 2021 databases. A final score U of 1.9310 is obtained on the unpublished test set maintained by the challenge organizers, which demonstrates the advantage of the two-step method in AFp event detection. The work is useful for assessing AF burden index for AFp patients.

Experimental Validation of Falling Liquid Film Models: Velocity Assumption and Velocity Field Comparison.

This publication focuses on the experimental validation of film models by comparing constructed and experimental velocity fields based on model and elementary experimental data. The film experiment covers Kapitza numbers Ka = 278.8 and Ka = 4538.6, a Reynolds number range of 1.6-52, and disturbance frequencies of 0, 2, 5, and 7 Hz. Compared to previous publications, the applied methodology has boundary identification procedures that are more refined and provide additional adaptive particle image velocimetry (PIV) method access to synthetic particle images. The experimental method was validated with a comparison with experimental particle image velocimetry and planar laser induced fluorescence (PIV/PLIF) results, Nusselt's theoretical prediction, and experimental particle tracking velocimetry (PTV) results of flat steady cases, and a good continuity equation reproduction of transient cases proves the method's fidelity. The velocity fields are reconstructed based on different film flow model velocity profile assumptions such as experimental film thickness, flow rates, and their derivatives, providing a validation method of film model by comparison between reconstructed velocity experimental data and experimental velocity data. The comparison results show that the first-order weighted residual model (WRM) and regularized model (RM) are very similar, although they may fail to predict the velocity field in rapidly changing zones such as the front of the main hump and the first capillary wave troughs.

Association of constitutive nuclear factor-kappaB activation with aggressive aspects and poor prognosis in cervical cancer.

INTRODUCTION: Although nuclear factor-kappaB (NF-kappaB) is generally believed to be involved in carcinogenesis, the relationship between NF-kappaB activation and progression of cervical cancer in clinical settings has not been reported. In this study, we investigated the association of NF-kappaB activation with aggressive aspects and prognosis in cervical cancer. METHODS: Nuclear factor-kappaB subunits p65 and p50 were detected in 159 paraffin tissues including normal cervical, precancerous (squamous intraepithelial lesions), and cervical carcinoma tissues by immunohistochemistry. Nuclear factor-kappaB nuclear translocation and DNA-binding activity in precancerous or carcinoma tissues were examined by Western blot and electrophoretic mobility shift assay, respectively. RESULTS: A gradual NF-kappaB activation from normal cervical epithelial cells to precancerous and carcinoma cells was detected by immunohistochemistry (nuclear expression of p65 and p50, P < 0.001), Western blot (NF-kappaB nuclear translocation), and electrophoretic mobility shift assay (enhanced DNA-binding activity). In 79 cancer tissues, increased nuclear p65, an active NF-kappaB form, was correlated with poor tumor grade, lymphatic metastasis, interstitial invasion, and larger tumor size (P < 0.05). Similarly, increased nuclear p50 was correlated with poor tumor grade, interstitial invasion, and larger tumor size (P < 0.05). Moreover, increased nuclear p65 was associated with lower survival rate in patients with cancer (P < 0.05). CONCLUSIONS: Constitutive NF-kappaB activation is correlated to tumor progression, aggressive behaviors, and poor prognosis in cervical cancer, suggesting that NF-kappaB is a tumor promoter, a prognostic indicator, and a possible therapeutic target for this malignant disease.

[Study of local immunity of lower genital tract infections].

OBJECTIVE: To investigate the profile of local immunity of vagina and the immune defense mechanisms against lower genital tract infections. METHODS: Vaginal lavage was collected from healthy women and patients of vulvovaginal candidiasis, bacterial vaginosis, Trichomonol vaginitis, human papilloma virus infection (VVC), and chlamydia trachomatis infection. Each group included 60 cases. The level of interleukin (IL)2, 4, 5, 13, 8 and human defensin 5 (HD5) were detected by enzyme linked immunosorbent assay(ELISA). RESULTS: (1) Cytokine of helper T cell 1(Th1): the level of IL-2 between healthy women and VVC/ bacterial vaginosis (BV)/ trichomonol vaginitis (TV)/ chlamydia trachomatis (CT) patients had no significant difference. The IL-2 level(96 +/- 33) x 10(-3) pg/L of human papilloma virus (HPV) infection patients was significantly higher than that of healthy women (P < 0.05). (2) Cytokine of helper T cell 2 (Th2): the level of IL-4 between healthy women and VVC/CT patients had no significant difference. The level of IL-5 between healthy women and BV patients had no significant difference. The IL-13 level (42 +/- 15) x 10(-3) pg/L of TV patients was significantly higher than that of healthy women (30 +/- 29) x 10(-3) pg/L (P < 0.05). The IL-4 level (103 +/- 28) x 10(-3) pg/L of HPV infection patients was significantly higher than that of healthy women (36 +/- 22) x 10(-3) pg/L (P < 0.05). (3) IL-8: the IL-8 level (5.8 +/- 2.7) pg/L of TV infection patients was significantly higher than that of healthy women (2.6 +/- 2.4) pg/L (P < 0.05). The level of IL-8 between healthy women and BV patients had no significant difference. (4) HD5: the HD5 level of TV, BV, VVC, HPV and CT infection patients were significantly higher than that of healthy women (P < 0.05). CONCLUSIONS: (1) HD5 plays an important role in the defence of vaginal epithelial cell. (2) Th2 may be more important than Thl in lower genital tract infections. (3) IL-8 plays an important role in extrinsic source infections.

Correlation of inhibitor of differentiation 1 expression to tumor progression, poor differentiation and aggressive behaviors in cervical carcinoma.

OBJECTIVE: To study the correlation of inhibitor of differentiation 1 (Id-1) to tumor invasion and metastasis by examining Id-1 expression levels in different stages of cervical carcinogenesis. METHODS: Id-1 mRNA and protein expression was detected in total of 171 cervical samples including precancerous and cancerous tissues by quantitative RT-PCR (qRT-PCR) and immunohistochemistry (IHC), respectively. Twenty-five normal cervical tissues were used as a normal control. Correlation between Id-1 positive rates and expression levels to cancer progression and clinicopathologic features was statistically analyzed. RESULTS: A gradual increase of Id-1 protein expression associated with cervical cancer progression was detected (4%, 16%, 50% and 75.9% in normal, low squamous intraepithelial lesion (LSIL), high squamous intraepithelial lesion (HSIL) and cancer tissue, respectively, p<0.001). A similar trend of Id-1 mRNA expression was also observed (1.3, 3.4 and 10.4 fold higher than normal tissues in LSIL, HSIL and cancer tissue, respectively, p<0.001). Furthermore, the Id-1 expression level was correlated to tumor grade (p=0.005), lymph node metastasis (p=0.001), interstitial invasive (p<0.001) and tumor size (p<0.001). These results suggest that high Id-1 expression is associated with tumor growth, invasion and metastasis. CONCLUSION: Id-1 expression is correlated to progression and aggressive behaviors in cervical cancer, suggesting a tumor-promoting role for Id-1 in progression of this malignancy.

[Expression and action of keratinocyte growth factor, keratinocyte growth factor receptor on CaSki cell].

OBJECTIVE: To investigate the expressions of keratinocyte growth factor (KGF), keratinocyte growth factor receptor (KGFR) in CaSki cell and action of keratinocyte growth factor on proliferation, migration of the CaSki cell. METHODS: ELISA and Western blot methods were used to determine the protein expressions of the KGF and KGFR in CaSki cell respectively: 3H-Thymidine incorporation method was used to determine the effect of recombinant human KGF and anti-KGF on CaSki cell proliferation; Millicell-PCF was used to determine the effect of recombinant human KGF, anti-KGF on CaSki cell migration. RESULTS: Both KGF and KGFR were expressing in the CaSki cell; Recombinant human KGF resulted in a increase in the proliferation and migration of CaSki cells; The proliferation and migration of CaSki cell became weak due to autocrine KGF neutralized by KGF antibodies (P < 0.05). CONCLUSION: Current results demonstrate that KGF and KGFR express in CaSki cell; Both autocrine and recombinant human KGF have the effect on CaSki cell proliferation and migration.

[Expression of keratinocyte growth factor and keratinocyte growth factor receptor and its impact on Hela cells].

OBJECTIVE: To identify the expression of keratinocyte growth factor (KGF) and keratinocyte growth factor receptor (KGFR) in Hela cells and the impact of keratinocyte growth factor on Hela cells. METHODS: Reverse transcriptase polymerase chainreaction (RT-PCR) method was employed to determine the gene expression of KGF and KGFR in Hela cells. The ELISA and Western blot methods were employed to determine the protein expression of the KGF and KGFR. The 3H-Thymidine incorporation method was employed to determine the impact of the KGF on the proliferation of Hela cells. RESULTS: The KGF and KGFR genes were expressed in the Hela cells. The KGF and KGFR proteins were expressed in the Hela cells. The Hela cells were stimulated to proliferate by the recombinant human KGF. The proliferation of the autocrine KGF in the Hela cells was neutralized by the KGF antibodies significantly (Dunnett's test, P