How to properly evaluate cardiac vagal tone in oncology studies: a state-of-the-art review.

Heart rate variability (HRV) analysis provides an assessment of cardiac vagal tone and consequently global cardiac health as well as systemic condition. In systemic diseases such as cancer and during treatments that affect the whole body, like chemotherapy, the vagus nerve activity is low and deregulated. Some studies focus on using HRV to predict mortality in oncology. However, in cancer patients, systemic alterations substantially increase artifacts during HRV measurement, especially atrial ectopic beats. Moreover, HRV may be altered by various factors (duration and time of measurement, breathing, drugs, and other confounding factors) that alter each metric in different ways. The Standard Deviation of all Normal to Normal intervals (SDNN) is the most commonly used metric to evaluate HRV in oncology, but it does not appear to be specific to the cardiac vagal tone. Thus, cardiac vagal activity diagnosis and vital prognosis of cancer patients can be biased. Our review presents the main HRV metrics that can be currently used in oncology studies and their links with vagus nerve and cancer. We present the influence of external factors and the required duration and time of measurement. Considering all these parameters, this review proposes seven key points for an assessment of HRV and cardiac vagal tone in patients with cancer.

On punctate white matter lesions in preterm infants: Is ultrasound diagnosis feasible?

OBJECTIVES: To observe hyperechoic nodular or punctate white matter lesions (HNPL) in a population of preterm infants using routine cranial ultrasound (cUS), to describe the characteristics of HNPL, and to compare them with punctate white matter lesions (PWML) detected in magnetic resonance imaging (MRI). DESIGN: Retrospective observational single-center cohort study. SETTING: Level 2B neonatal unit in France. PATIENTS: 307 infants born <33 weeks gestation undergoing routine cUS with a total of 961 cUS performed. MAIN OUTCOME MEASURES: Description of lesions (HNPL/PWML): presence or absence, number, size, location, and structural distribution. RESULTS: Among the 307 included infants, 63 (20.5%) had at least one cerebral lesion, with 453 HNPL for 63 infants. HNPL were numerous (more than three in 66.6% of cases), primarily grouped in clusters (76.2%), located near the lateral ventricles (96.8%), and measuring more than 2 mm (79%). HNPL were diagnosed on day 29 on average and persisted until term. Overall, 43 MRI were performed in 307 infants, on average 18.9 days after last cUS, in 21 of those the indication was presence of HPNL on cUS. Of these 21 MRI, 14/21 presented 118 PWML compared to 173 HNPL on cUS. In the remaining MRI (7/21), no PWML were detected compared to 47 HNPL on cUS. CONCLUSIONS: In our population of 307 preterm infants, cUS allowed the diagnosis of HNPL, with a large similarity to PWML in MRI and a better sensitivity. But in the absence of data on inter-observer variability, we cannot exclude overdiagnosis of HNPL.

Hearing aid benefits in children with mild bilateral hearing loss: AUDIO-INFANS study.

OBJECTIVES: There is a lack of consensus regarding the definition, consequences, and management of mild bilateral hearing loss in children. The objective of this study is to analyze the benefit of hearing aids in children with mild bilateral hearing loss by evaluating their functional hearing. METHODS: This retrospective study included 57 children with mild bilateral hearing loss between 20 dB HL and 40 dB HL. Pure tone and speech audiometry thresholds were assessed with and without hearing aids. Two groups were subsequently formed: group E with an effective use of hearing aids (>10 h/day), and group IE whose use of hearing aids was deemed ineffective (<10 h/day). RESULTS: Without hearing aids, the initial median of hearing level was 35 dB HL and 36 dB HL in the right and left ears, respectively, compared to 23 dB HL and 25 dB HL with hearing aids. The Lafon test performed on 25 children at 55 dB HL and 65 dB HL showed results ranging from 0% to 100% without hearing aids and from 90% to 100% with hearing aids. Scores obtained with hearing aids were significantly higher than those without them at an average speech level. Median age at diagnosis and at prescription were found to significantly influence the daily use of hearing aids. CONCLUSIONS: Our results show that in the case of mild bilateral hearing loss, hearing aids have positive effects on the functional hearing of children and help them to no longer be disadvantaged. This study highlights the need to provide regular support to these children to ensure their optimal care in the event of hearing-related problems. Coordination between the different professionals working with these children is also necessary for their follow-up and appropriate management.

Side scatter intensity is highly heterogeneous in undifferentiated pluripotent stem cells and predicts clonogenic self-renewal.

In culture, human pluripotent stem cells (PSCs) are phenotypically (for instance, the SSEA3 expression level) and functionally (capacity to survive after single-cell dissociation) heterogeneous. We report here that the side scatter (SSC) signal measured by flow cytometry, a variable correlated with membrane irregularity and cell granularity, is very high in PSCs, even higher than in blood polymorphonuclear cells, and markedly heterogeneous. Moreover, SSC intensity rapidly and strongly decreases upon PSC differentiation into any of the three germ layers. PSCs with high SSC (HSSC cells) or low SSC (LSSC cells) values both express pluripotency markers, but HSSC cells are characterized by more frequent simultaneous expression of the membrane pluripotency factors SSEA3, SSEA4, TRA-1-81, TRA-1-60, and CD24 and by a higher mitochondrial content. Functionally, HSSC cells are more likely to generate colonies upon single-cell passage than LSSC cells. SSC monitoring might provide a simple, but robust and rapid method to estimate pluripotency variations in culture and unveils a new phenotypic and functional heterogeneity in PSCs.

Human pluripotent stem cells: from biology to cell therapy.

Human pluripotent stem cells (PSCs), encompassing embryonic stem cells and induced pluripotent stem cells, proliferate extensively and differentiate into virtually any desired cell type. PSCs endow regenerative medicine with an unlimited source of replacement cells suitable for human therapy. Several hurdles must be carefully addressed in PSC research before these theoretical possibilities are translated into clinical applications. These obstacles are: (1) cell proliferation; (2) cell differentiation; (3) genetic integrity; (4) allogenicity; and (5) ethical issues. We discuss these issues and underline the fact that the answers to these questions lie in a better understanding of the biology of PSCs. To contribute to this aim, we have developed a free online expression atlas, Amazonia!, that displays for each human gene a virtual northern blot for PSC samples and adult tissues (http://www.amazonia.transcriptome.eu).