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991.

Background

Although infant lung function (ILF) testing is widely practiced in developed Western countries it is not typically performed in Eastern countries, and lung measurements are scarce for Asian infants. Therefore, this study aimed to establish normal reference values for Taiwanese infants.

Materials and Methods

Full-term infants without any chronic diseases and major anomalies were enrolled in the Prediction of Allergies in Taiwanese Children (PATCH) cohort study. Detailed medical data, such as body weight and length, birth history, and histories of previous illness and hospitalization were recorded. Lung function measurements such as analysis of tidal breathing, passive respiratory mechanics, and forced tidal expiratory flow-volume curves were obtained through Jaeger Masterscreen BabyBody Paediatrics System. Multiple linear analyses were performed to determine various parameters of the lung function tests.

Results

ILF test parameters were collected from 126 infants, and 189 tests were performed. The results revealed that the ratio of time to peak expiratory flow to total expiratory time, the ratio of volume to peak expiratory flow to total expiratory volume, and the ratio of inspiratory time to total respiratory time remained relatively constant despite differences in age. However, body length is the strongest independent variable influencing tidal volume, respiratory rate, resistance, compliance, and maximal expiratory flow at functional residual capacity.

Conclusion

According to our review of relevant literature, this is the first study to establish a reference data of ILF tests in the Asian population. This study provided reference values and regression equations for several variables of lung function measurements in healthy infants aged less than 2 years. With these race-specific reference data, ILF can more precisely and efficiently diagnose respiratory diseases in infants of Chinese ethnicity.  相似文献   
992.

Background & aims

Current hepatocellular carcinoma (HCC) staging systems only use baseline characteristics to predict outcome. We aimed to explore modifiable factors of the prognosis in HCC cases had undergone non-surgical treatment.

Methods

All HCC cases in Kaohsiung Chang Gung Memorial hospital in southern Taiwan from 2002 to 2012 must met all below criteria: (1) met international diagnostic guidelines, (2) underwent the initial treatments in our hospital (3) treated by non-surgical treatment modalities and (4) survived more than two years, with follow-up time longer than five years.

Results

A total 698 patients were enrolled: 451 (24.6%, group A) survivied between 2 to 5 years, and 247 (13.5%, group B) had survived > 5 years. Aside from liver function reserve and BCLC stages, four interventional factors: initial treatment modality, outcomes of 1st or 2nd treatment, and anti-viral therapy to chronic viral hepatitis were associated with prognosis. After propensity score matching, multiple logistic regression of 223 well-matched pairs showed that recurrence within one year after 1st treatment (OR: 2.17, 95% CI: 1.35–3.48), incomplete 2nd treatment (2.01, 1.27–3.17) and absence of anti-viral agents (1.68, 1.09–2.59) were independent poor prognostic factors.

Conclusion

Complete treatment and anti-viral agents to chronic hepatitis were both independent modifiable prognostic factors of HCC patients had undergone non-surgical treatment. Based on these findings, timely treatment to achieve maximal locoregional control and anti-viral treatment should be provided as possible.  相似文献   
993.

Background

Coronary artery calcium (CAC) assessed by non-contrast cardiac CT has been shown to be an independent factor from the Framingham risk factors in predicting cardiovascular events. However, many patients with acute coronary syndrome (ACS) have low CAC score. A recent study that re-analyzed the previous CAC CT scan of MESA cohort showed that in subjects with global lower density, CAC was associated with higher risk of ACS. We aimed to further evaluate the characteristics of CAC attenuation features in ACS subjects, in comparison to asymptomatic and stable angina pectoris (SAP) groups.

Methods

In a period of 18 months, 524 consecutive subjects received standard CAC CT scans in our department; 278 of 524 subjects with presence of CAC (225 men, age = 60.6±9.5 years; ACS = 41, SAP = 78, asymptomatic = 159) were enrolled. Agatston score, number of plaques (NP) per subject and mean (HMEAN) and standard deviation (HSD) of attenuation of each calcified plaque were measured. Three regression models to distinguish the groups were built: model 1, conventional risk factors only; model 2, Agatston score plus model 1; model 3, plaque attenuation features plus model 2.

Results

Agatston score in ACS group (median = 112.9) was higher than in the asymptomatic group (median = 54.4, P = 0.028) and similar to the SAP group (median = 237.8, P = 0.428). Calcified plaques in the ACS group showed lower (HMEAN = 180.5) and more homogenous (HSD = 31.2) attenuation than those of the asymptomatic group (HMEAN = 205.9, P = 0.002; HSD = 52.4, P = 0.006) and the SAP group (HMEAN = 204.1, P = 0.016; HSD = 54.4, P = 0.011). Model 3 significantly improved the distinction between ACS and asymptomatic groups (area under curve [AUC] = 0.93) as compared to model 2 (AUC = 0.83, P = 0.003) and model 1 (AUC = 0.79, P = 0.001).

Conclusions

Calcified plaques in the ACS group were characteristically of low and homogenous CT attenuation. With validation in a large cohort, analysis of CT attenuation features may improve risk stratification of ACS using CAC CT scan.  相似文献   
994.
Trefoil factor 3 (TFF3), also called intestinal trefoil factor or Itf, is a 59 amino acid peptide found as a homodimer predominantly along the gastrointestinal tract and in serum. TFF3 expression is elevated during gastrointestinal adenoma progression and has been shown to promote mucosal wound healing. Here we show that in contrast to other trefoil factor family members, TFF1 and TFF2, TFF3 is highly expressed in mouse duodenum, jejunum and ileum and that its expression is regulated by food intake. Overexpression of TFF3 using a recombinant adeno-associated virus (AAV) vector, or daily administration of recombinant TFF3 protein in vivo improved glucose tolerance in a diet-induced obesity mouse model. Body weight, fasting insulin, triglyceride, cholesterol and leptin levels were not affected by TFF3 treatment. Induction of mucinous metaplasia was observed in mice with AAV-mediated TFF3 overexpression, however, no such adverse histological effect was seen after the administration of recombinant TFF3 protein. Altogether these results suggest that the therapeutic potential of targeting TFF3 to treat T2D may be limited.  相似文献   
995.
996.
Multiple epigenetic factors play a critical role in cell proliferation and differentiation. However, their function in embryogenesis, especially in neural development, is currently unclear. The Trithorax group (TrxG) homolog KMT2A (MLL1) is an important epigenetic regulator during development and has an especially well‐defined role in hematopoiesis. Translocation and aberrant expression of KMT2A is often observed in many tumors, indicating its proto‐oncogenic character. Here, we show that Kmt2a was essential for neural development in zebrafish embryos. Disrupting the expression of Kmt2a using morpholino antisense oligonucleotides and a dominant‐negative variant resulted in neurogenic phenotypes, including downregulated proliferation of neural progenitors, premature differentiation of neurons, and impaired gliogenesis. This study therefore revealed a novel function of Kmt2a in cell proliferation and differentiation, providing further insight into the function of TrxG proteins in neural development and brain tumors. © 2014 Wiley Periodicals, Inc. Develop Neurobiol 75: 452–462, 2015  相似文献   
997.

Background

L-type calcium current reactivation plays an important role in development of early afterdepolarizations (EADs) and torsades de pointes (TdP). Secondary intracellular calcium (Cai) rise is associated with initiation of EADs.

Objective

To test whether inhibition of sarcoplasmic reticulum (SR) Ca2+ cycling suppresses secondary Cai rise and genesis of EADs.

Methods

Langendorff perfusion and dual voltage and Cai optical mapping were conducted in 10 rabbit hearts. Atrioventricular block (AVB) was created by radiofrequency ablation. After baseline studies, E4031, SR Ca2+ cycling inhibitors (ryanodine plus thapsigargin) and nifedipine were then administrated subsequently, and the protocols were repeated.

Results

At baseline, there was no spontaneous or pacing-induced TdP. After E4031 administration, action potential duration (APD) was significantly prolonged and the amplitude of secondary Cai rise was enhanced, and 7 (70%) rabbits developed spontaneous or pacing-induced TdP. In the presence of ryanodine plus thapsigargin, TdP inducibility was significantly reduced (2 hearts, 20%, p = 0.03). Although APD was significantly prolonged (from 298 ± 30 ms to 457 ± 75 ms at pacing cycle length of 1000 m, p = 0.007) by ryanodine plus thapsigargin, the secondary Cai rise was suppressed (from 8.8 ± 2.6% to 1.2 ± 0.9%, p = 0.02). Nifedipine inhibited TdP inducibility in all rabbit hearts.

Conclusion

In this AVB and long QT rabbit model, inhibition of SR Ca2+ cycyling reduces the inducibility of TdP. The mechanism might be suppression of secondary Cai rise and genesis of EADs.  相似文献   
998.
Mitogen-activated protein kinase (MAPK) activation controls diverse cellular functions including cellular survival, proliferation, and apoptosis. Tuning of MAPK activation is counter-regulated by a family of dual-specificity phosphatases (DUSPs). IL-33 is a recently described cytokine that initiates Th2 immune responses through binding to a heterodimeric IL-33Rα (ST2L)/IL-1α accessory protein (IL-1RAcP) receptor that coordinates activation of ERK and NF-κB pathways. We demonstrate here that DUSP5 is expressed in eosinophils, is upregulated following IL-33 stimulation and regulates IL-33 signaling. Dusp5−/− mice have prolonged eosinophil survival and enhanced eosinophil effector functions following infection with the helminth Nippostrongylus brasiliensis. IL-33-activated Dusp5−/− eosinophils exhibit increased cellular ERK1/2 activation and BCL-XL expression that results in enhanced eosinophil survival. In addition, Dusp5−/− eosinophils demonstrate enhanced IL-33-mediated activation and effector functions. Together, these data support a role for DUSP5 as a novel negative regulator of IL-33-dependent eosinophil function and survival.  相似文献   
999.
1000.
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