Investigating fractal property and respiratory modulation of human heartbeat time series using empirical mode decomposition

The human heartbeat interval reflects a complicated composition with different underlying modulations and the reactions against environmental inputs. As a result, the human heartbeat interval is a complex time series and its complexity can be scaled using various physical quantifications, such as the property of long-term correlation in detrended fluctuation analysis (DFA). Recently, empirical mode decomposition (EMD) has been shown to be a dyadic filter bank resembling those involved in wavelet decomposition. Moreover, the hierarchy of the extracted modes may be exploited for getting access to the Hurst exponent, which also reflects the property of long-term correlation for a stochastic time series. In this paper, we present significant findings for the dynamic properties of human heartbeat time series by EMD. According to our results, EMD provides a more accurate access to long-term correlation than Hurst exponent does. Moreover, the first intrinsic mode function (IMF 1) is an indicator of orderliness, which reflects the modulation of respiratory sinus arrhythmia (RSA) for healthy subjects or performs a characteristic component similar to that decomposed from a stochastic time series for subjects with congestive heart failure (CHF) and atrial fibrillation (AF). In addition, the averaged amplitude of IMF 1 acts as a parameter of RSA modulation, which reflects significantly negative correlation with aging. These findings lead us to a better understanding of the cardiac system.     

Myeloperoxidase in the plasma and placenta of normal pregnant women and women with pregnancies complicated by preeclampsia and intrauterine growth restriction

Myeloperoxidase (MPO) is a heme protein produced and released by activated neutrophils and monocytes, and increased MPO is considered important in the pathophysiology of cardiovascular diseases (CVD). Accumulating evidence suggests that preeclampsia (PE), idiopathic intrauterine growth restriction (IUGR), and CVD share many similar metabolic disturbances, including an enhanced systemic inflammatory response and endothelial dysfunction. We hypothesized that MPO plays an important role in the development of PE and IUGR. Plasma samples were collected mid-gestation and at delivery from women with normal pregnancies (n?=?40) and those who subsequently developed PE (n?=?20), IUGR (n?=?11) or both (PE?+?IUGR, n?=?8). Placental samples were obtained immediately after delivery from 22 women with normal pregnancies, 19 women with PE, 14 women with IUGR, and 14 women with PE?+?IUGR. The MPO concentrations were measured using ELISA. Women with PE?+?IUGR had significantly higher plasma MPO before delivery than normal pregnant women. There was no difference in plasma levels at mid-gestation or the placental concentrations between women with normal pregnancies and those who developed PE, IUGR, or PE?+?IUGR. Using explants prepared from the placentas of 8 women with normal pregnancies and 8 women with PE, we found no difference in the levels of MPO in the tissue homogenates and culture media between these two groups of women. Together, these results indicate that increased maternal circulating MPO in women with PE?+?IUGR is likely a result of enhanced systemic inflammation caused by the established disease rather than a primary pathophysiological factor.     

Hypoadiponectinemia: A useful marker of dyslipidemia in women with polycystic ovary syndrome

ObjectiveAdiponectin plays a role in obesity, lipid metabolism, and anti-inflammation. Women with polycystic ovary syndrome (PCOS) are also at risk for dyslipidemia. Therefore, we investigated the association between adiponectin levels and the lipid profile including high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and triglycerides (TGs) in women with PCOS and contemplated what role adiponectin might play in dyslipidemia with PCOS.Materials and MethodsWe recruited 118 young Taiwanese women with PCOS. The women enrolled were not taking any medication and those with other systemic diseases of nonovarian origin, which could have affected the hypothalamic–pituitary–ovarian axis, were excluded. The serum lipid profile, metabolic and hormonal parameters, and adiponectin were measured. The lipid profile and adiponectin were analyzed and adjusted for age, body mass index (BMI), homeostasis model assessment-insulin resistance (HOMA-IR), and sex hormone-binding globulin (SHBG).ResultsIn a simple linear regression, adiponectin was significantly inversely related to LDL-C and TGs, but positively related to HDL-C (all p < 0.001) after logarithmic transformation. In the multiple linear regression, adiponectin was significantly related to HDL-C (p < 0.001) independent of age, BMI, HOMA-IR, and SHBG after logarithmic transformation. Using a logistic regression, the odds ratio was 0.088 between the association of increased adiponectin and abnormal HDL-C (≤50 mg/dL).ConclusionsWe demonstrated that adiponectin is an independent biomarker that is positively and evidently related to HDL-C and TGs in women with PCOS. Hypoadiponectinemia may be a useful marker of dyslipidemia in women with PCOS.     

The Association of eNOS G894T Polymorphism with Metabolic Syndrome and Erectile Dysfunction

IntroductionAccumulated evidences have outlined the potential relation between insulin resistance and endothelial dysfunction. The impaired ability of endothelium to synthesize or release nitric oxide may provide a common pathophysiological mechanism in the development of metabolic syndrome (MtS) and erectile dysfunction (ED).AimThe aim of this article was to investigate the genetic susceptibility of endothelial nitric oxide synthase (eNOS) G894T polymorphism underlying the development of both disorders.MethodsA total of 590 subjects with a mean (standard deviation) age of 55.3 years (4.1) were enrolled during a free health screening. Complete clinical data and questionnaires were taken for all subjects. Multivariate logistic regression analysis was used to determine the independent predictors of MtS and ED. The eNOS G894T polymorphism was determined using a polymerase chain reaction‐restriction fragment length polymorphism method.Main Outcome MeasuresThe definition of MtS was according to the modified criteria developed by the Bureau of Health Promotion in Taiwan. Patients with ED were defined as those having a five‐item International Index of Erectile Function (IIEF‐5) <21.ResultsOur results showed that the eNOS 894T allele carriers had significantly higher prevalence of MtS and ED (odds ratio [OR] = 1.64, 95% confidence interval [CI] = 1.05～2.56, P = 0.02 and OR = 1.76, 95% CI = 1.11～2.80, P = 0.01, respectively) after adjustment for each other and age. Also the T allele carriers had significantly lower IIEF‐5 score and more MtS components than G allele carriers (P < 0.01 and P < 0.01, respectively), which were significantly associated with an increment of the T allele number (P < 0.05).ConclusionsThe eNOS 894T allele carriers are at greater risk for both MtS and ED, suggesting that eNOS G894T gene polymorphism might play an implication as a common genetic susceptibility factor to develop both disorders. Lee Y‐C, Huang S‐P, Liu C‐C, Yang Y‐H, Yeh H‐C, Li W‐M, Wu W‐J, Wang C‐J, Juan Y‐S, Huang C‐N, Hour T‐C, Chang C‐F, and Huang C‐H. The Association of eNOS G894T polymorphism with metabolic syndrome and erectile dysfunction. J Sex Med 2012;9:837–843.     

Group B Streptococcal infection in neonates and colonization in pregnant women: An epidemiological retrospective analysis

Background

Group B Streptococcus (GBS) infection is one of the major causes of neonatal morbidity and mortality. Universal GBS screening with intrapartum antibiotic prophylaxis (IAP) in pregnant women were initiated in 2012 in Taiwan. This study aimed to analyze the most recent maternal GBS colonization rate and the changes in neonatal GBS infection rate from 2011 to 2016.

A system of corticotropin releasing factor-containing amacrine cells in the rat retina

Immunohistochemical processing of Long-Evans retina wholemounts using an antiserum directed against rat, human corticotropin releasing factor revealed a group of immunoreactive amacrine cells. Two subpopulations could be distinguished based primarily on the location of their cell bodies. One subpopulation had cell bodies situated along the junction of the inner nuclear layer and the inner plexiform layer. The other subpopulation had cell bodies in the ganglion cell layer. The latter was judged to be displaced amacrine cells since double-label experiments indicated that the pattern of corticotropin releasing factor-like immunoreactive staining in the ganglion cell layer did not coincide with that of ganglion cells labeled retrogradely with fluorogold. Corticotropin releasing factor-like immunoreactive amacrine cells on either side of the inner plexiform layer emitted processes which ramified extensively in sublamina 5 and, to a lesser degree, in sublamina 4. A minority of these cells also sent a single process to ramify in sublamina 1. Throughout the retina, corticotropin releasing factor-like immunoreactive cells were distributed relatively evenly, with a tendency to peak in the superior temporal region. Despite the anatomical classification into two subpopulations, it is proposed that the corticotropin releasing factor-like immunoreactive cells are functionally one system, influencing preferentially synaptic interactions associated with the inner half of the inner plexiform layer. The results of this study provide anatomical basis for further investigations of corticotropin releasing factor as a putative peptidergic neurotransmitter in the retina.     

The Chinese version of the Parenting Stress Index: a psychometric study

This study examined the psychometric properties of a Chinese version of the Parenting Stress Index/Short Form (PSI/SF). A 15-item simplified PSI/SF (S-PSI/SF) was subsequently developed which maintained a level of reliability and validity similar to the full version. The Chinese PSI/SF was tested on 149 parents (100 mothers, 49 fathers) of pediatric cancer patients in Taiwan. Psychometric testing was conducted using item analysis, Cronbach's alpha and confirmatory factor analysis. The S-PSI/SF was constructed based on the item analysis of the PSI/SF. Both the PSI/SF and S-PSI/SF produced good reliability coefficients. Confirmatory factor analyses indicated that both PSI/SF and S-PSI/SF met all criteria for goodness of fit. Compared with the PSI/SF, the S-PSI/SF demonstrated better internal consistency and overall fit at the one-subscale level, and satisfactory overall fit at two- and three-subscale levels. Despite the limited number of items included, the S-PSI/SF had a very good factor structure. No gender difference in parenting distress index was observed between mothers and fathers of pediatric cancer patients. Conclusion: The 15-item S-PSI/SF is a brief, easily administered instrument that has evidence of reliability and validity in Taiwanese parents of children with cancer. It could serve as a valuable assessment tool in clinical practice to identify parenting stress with a need for intervention.