Prenatal stress and balance of the child's cardiac autonomic nervous system at age 5-6 years

Objective

Autonomic nervous system (ANS) misbalance is a potential causal factor in the development of cardiovascular disease. The ANS may be programmed during pregnancy due to various maternal factors. Our aim is to study maternal prenatal psychosocial stress as a potential disruptor of cardiac ANS balance in the child.

Methods

Mothers from a prospective birth cohort (ABCD study) filled out a questionnaire at gestational week 16 [IQR 12–20], that included validated instruments for state anxiety, depressive symptoms, pregnancy-related anxiety, parenting daily hassles and job strain. A cumulative stress score was also calculated (based on 80^th percentiles). Indicators of cardiac ANS in the offspring at age 5–6 years are: pre-ejection period (PEP), heart rate (HR), respiratory sinus arrhythmia (RSA) and cardiac autonomic balance (CAB), measured with electrocardiography and impedance cardiography in resting supine and sitting positions.

Results

2,624 mother-child pairs, only single births, were available for analysis. The stress scales were not significantly associated with HR, PEP, RSA and CAB (p≥0.17). Accumulation of maternal stress was also not associated with HR, PEP, RSA and CAB (p≥0.07).

Conclusion

Results did not support the hypothesis that prenatal maternal psychosocial stress deregulates cardiac ANS balance in the offspring, at least in rest, and at the age of five-six years.     

Availability of Volunteer-Led Home-Based Care System and Baseline Factors as Predictors of Clinical Outcomes in HIV-Infected Patients in Rural Zambia

Background

We assessed the impact of home-based care (HBC) for HIV+ patients, comparing outcomes between two groups of Zambians receiving antiretroviral therapy (ART) who lived in villages with and without HBC teams.

Methods

We conducted a retrospective cohort study using medical charts from Macha Mission Hospital, a hospital providing HIV care in Zambia''s rural Southern Province. Date of birth, date of ART initiation, place of residence, sex, body mass index (BMI), CD4+ cell count, and hemoglobin (Hgb) were abstracted. Logistic regression was used to test our hypothesis that HBC was associated with treatment outcomes.

Results

Of 655 patients, 523 (80%) were eligible and included in the study. There were 428 patients (82%) with favorable outcomes (alive and on ART) and 95 patients (18%) with unfavorable outcomes (died, lost to follow-up, or stopped treatment). A minority of the 523 eligible patients (n = 84, 16%) lived in villages with HBC available. Living in a village with HBC was not significantly associated with treatment outcomes; 80% of patients in a village with HBC had favorable outcomes, compared to 82% of patients in a village without HBC (P = 0.6 by χ²). In bivariable analysis, lower BMI (P<0.001), low CD4+ cell count (P = 0.02), low Hgb concentration (P = 0.02), and older age at ART initiation (P = 0.047) were associated with unfavorable outcomes. In multivariable analysis, low BMI remained associated with unfavorable outcomes (P<0.001).

Conclusions

We did not find that living in a village with HBC available was associated with improved treatment outcomes. We speculate that the ART clinic''s rigorous treatment preparation before ART initiation and continuous adherence counseling during ART create a motivated group of patients whose outcomes did not improve with additional HBC support. An alternative explanation is that the quality of the HBC program is suboptimal.     

Different anthropometric adiposity measures and their association with cardiovascular disease risk factors: a meta-analysis

Objectives

To investigate which anthropometric adiposity measure has the strongest association with cardiovascular disease (CVD) risk factors in Caucasian men and women without a history of CVD.

Design

Systematic review and meta-analysis.

Methods

We searched databases for studies reporting correlations between anthropometric adiposity measures and CVD risk factors in Caucasian subjects without a history of CVD. Body mass index (BMI), waist circumference, waist-to-hip ratio, waist-to-height ratio and body fat percentage were considered the anthropometric adiposity measures. Primary CVD risk factors were: systolic blood pressure, diastolic blood pressure, high density lipoprotein (HDL) cholesterol, triglycerides and fasting glucose. Two independent reviewers performed abstract, full text and data selection.

Results

Twenty articles were included describing 21,618 males and 24,139 females. Waist circumference had the strongest correlation with all CVD risk factors for both men and women, except for HDL and LDL in men. When comparing BMI with waist circumference, the latter showed significantly better correlations to CVD risk factors, except for diastolic blood pressure in women and HDL and total cholesterol in men.

Conclusions

We recommend the use of waist circumference in clinical and research studies above other anthropometric adiposity measures, especially compared with BMI, when evaluating CVD risk factors.     

Umbilical cord clamping in term piglets: a useful model to study perinatal asphyxia?

Perinatal asphyxia results in tissue and cellular changes during the reperfusion period and clinical signs like perinatal mortality and decreased vitality at birth in newborn piglets. This study aimed to develop and validate a model of birth asphyxia, mimicking the evolvement of birth asphyxia in natural farrowings by conducting umbilical cord clamping (UCC) in term piglets during caesarean sections under general anaesthesia. In total 23 piglets were subjected to 5-8min of UCC and 24 piglets served as controls. Acid-base balance values and heart rates measured before UCC remained fairly constant throughout the surgical procedure, indicating nearly identical starting conditions of piglets within and between litters. UCC resulted in a significant, mild, mixed respiratory-metabolic acidosis (pH 7.22, pCO(2) 9.8kPa, BE(ecf) 2mmol/L, lactate 6.5mmol/L; controls: pH 7.31, pCO(2) 8.5kPa, BE(ecf) 5mmol/L, lactate 4mmol/L) at 10min after birth (defined as simultaneous cutting of the umbilical cord and removal of a plastic bag that had been placed over the head to avoid air intake). Heart rates were significantly decreased during UCC (range: 83-107beats/min versus 128-134beats/min in controls). Rectal temperatures and changes in body weight until 72h of life were not affected by UCC. Interestingly, four control and seven clamped piglets did not survive as no independent respiration could be attained. Birth weights and duration of UCC of these piglets did not differ significantly from those in surviving control and clamped piglets. In conclusion the mixed respiratory-metabolic acidosis arising in the surviving clamped piglets is not as severe as can be expected in highly asphyxiated, vaginally delivered newborn piglets. Repeatability of the model is compromised by considerable variation in the individual response to UCC.     

In-vivo range of motion of the subtalar joint using computed tomography

Understanding in vivo subtalar joint kinematics is important for evaluation of subtalar joint instability, the design of a subtalar prosthesis and for analysing surgical procedures of the ankle and hindfoot. No accurate data are available on the normal range of subtalar joint motion. The purpose of this study was to introduce a method that enables the quantification of the extremes of the range of motion of the subtalar joint in a loaded state using multidetector computed tomography (CT) imaging. In 20 subjects, an external load was applied to a footplate and forced the otherwise unconstrained foot in eight extreme positions. These extreme positions were foot dorsiflexion, plantarflexion, eversion, inversion and four extreme positions in between the before mentioned positions. CT images were acquired in a neutral foot position and each extreme position separately. After bone segmentation and contour matching of the CT data sets, the helical axes were determined for the motion of the calcaneus relative to the talus between four pairs of opposite extreme foot positions. The helical axis was represented in a coordinate system based on the geometric principal axes of the subjects’ talus. The greatest relative motion between the calcaneus and the talus was calculated for foot motion from extreme eversion to extreme inversion (mean rotation about the helical axis of 37.3±5.9°, mean translation of 2.3±1.1 mm). A consistent pattern of range of subtalar joint motion was found for motion of the foot with a considerable eversion and inversion component.     

CLIP-170 tracks growing microtubule ends by dynamically recognizing composite EB1/tubulin-binding sites

The microtubule cytoskeleton is crucial for the internal organization of eukaryotic cells. Several microtubule-associated proteins link microtubules to subcellular structures. A subclass of these proteins, the plus end–binding proteins (+TIPs), selectively binds to the growing plus ends of microtubules. Here, we reconstitute a vertebrate plus end tracking system composed of the most prominent +TIPs, end-binding protein 1 (EB1) and CLIP-170, in vitro and dissect their end-tracking mechanism. We find that EB1 autonomously recognizes specific binding sites present at growing microtubule ends. In contrast, CLIP-170 does not end-track by itself but requires EB1. CLIP-170 recognizes and turns over rapidly on composite binding sites constituted by end-accumulated EB1 and tyrosinated α-tubulin. In contrast to its fission yeast orthologue Tip1, dynamic end tracking of CLIP-170 does not require the activity of a molecular motor. Our results demonstrate evolutionary diversity of the plus end recognition mechanism of CLIP-170 family members, whereas the autonomous end-tracking mechanism of EB family members is conserved.