Multimodal Assessment of the Pulse Rate Variability Analysis Module of a Photoplethysmography-Based Telemedicine System.

Alterations of heart rate variability (HRV) are associated with various (patho)physiological conditions; therefore, HRV analysis has the potential to become a useful diagnostic module of wearable/telemedical devices to support remote cardiovascular/autonomic monitoring. Continuous pulse recordings obtained by photoplethysmography (PPG) can yield pulse rate variability (PRV) indices similar to HRV parameters; however, it is debated whether PRV/HRV parameters are interchangeable. In this study, we assessed the PRV analysis module of a digital arterial PPG-based telemedical system (SCN4ALL). We used Bland-Altman analysis to validate the SCN4ALL PRV algorithm to Kubios Premium software and to determine the agreements between PRV/HRV results calculated from 2-min long PPG and ECG captures recorded simultaneously in healthy individuals (n = 33) at rest and during the cold pressor test, and in diabetic patients (n = 12) at rest. We found an ideal agreement between SCN4ALL and Kubios outputs (bias < 2%). PRV and HRV parameters showed good agreements for interbeat intervals, SDNN, and RMSSD time-domain variables, for total spectral and low-frequency power (LF) frequency-domain variables, and for non-linear parameters in healthy subjects at rest and during cold pressor challenge. In diabetics, good agreements were observed for SDNN, LF, and SD2; and moderate agreement was observed for total power. In conclusion, the SCN4ALL PRV analysis module is a good alternative for HRV analysis for numerous conventional HRV parameters.

High-density real-time PCR-based in vivo toxicogenomic screen to predict organ-specific toxicity.

Toxicogenomics, based on the temporal effects of drugs on gene expression, is able to predict toxic effects earlier than traditional technologies by analyzing changes in genomic biomarkers that could precede subsequent protein translation and initiation of histological organ damage. In the present study our objective was to extend in vivo toxicogenomic screening from analyzing one or a few tissues to multiple organs, including heart, kidney, brain, liver and spleen. Nanocapillary quantitative real-time PCR (QRT-PCR) was used in the study, due to its higher throughput, sensitivity and reproducibility, and larger dynamic range compared to DNA microarray technologies. Based on previous data, 56 gene markers were selected coding for proteins with different functions, such as proteins for acute phase response, inflammation, oxidative stress, metabolic processes, heat-shock response, cell cycle/apoptosis regulation and enzymes which are involved in detoxification. Some of the marker genes are specific to certain organs, and some of them are general indicators of toxicity in multiple organs. Utility of the nanocapillary QRT-PCR platform was demonstrated by screening different references, as well as discovery of drug-like compounds for their gene expression profiles in different organs of treated mice in an acute experiment. For each compound, 896 QRT-PCR were done: four organs were used from each of the treated four animals to monitor the relative expression of 56 genes. Based on expression data of the discovery gene set of toxicology biomarkers the cardio- and nephrotoxicity of doxorubicin and sulfasalazin, the hepato- and nephrotoxicity of rotenone, dihydrocoumarin and aniline, and the liver toxicity of 2,4-diaminotoluene could be confirmed. The acute heart and kidney toxicity of the active metabolite SN-38 from its less toxic prodrug, irinotecan could be differentiated, and two novel gene markers for hormone replacement therapy were identified, namely fabp4 and pparg, which were down-regulated by estradiol treatment.

Toxicogenomics screening of small molecules using high-density, nanocapillary real-time PCR.

Compounds which induce toxicity through similar mechanisms lead to characteristic gene expression patterns. The concept that structurally similar compounds may have similar biological profiles, the so-called generalized neighborhood behavior, is less obvious to be demonstrated. We screened 625 compounds from a fully combinatorial library for their gene expression profiles in vitro over a selected toxicity panel of 56 genes. We used the novel nanocapillary, quantitative real-time PCR OpenArray technology that is coupling outstanding analytical performance with the medium-throughput ideal for such a sample-per-feature ratio. Applying a hybrid clustering on the gene expression data, correlation was analyzed between molecular scaffold and biological fingerprint. Structurally highly dissimilar, but similarly hepatotoxic compounds show similar fingerprint on our toxicity panel, however compounds of the same scaffold and of unknown biological effect do not always share similar fingerprints. Out of 12 different scaffolds, 4 families show non-correlating, uniform distribution among clusters whilst 8 families show neighborhood behavior of varying strength. Structurally not similar compounds may have highly similar biological activity, on the other hand, compounds of the same scaffold family do not all share the same biological effects based on toxicology related gene expression fingerprint.

Do lunar cycles influence in vitro fertilization results?

PURPOSE: Our objective was to investigate the lunar influence on IVF-ET outcomes. METHODS: Between 1992 and 1999 we have completed 7572 preprogrammed IVF-ET treatment cycles with the same stimulation protocol in two outpatient units. (Vienna, Austria and Budapest, Hungary) Multiple regression (SAS; proc Logistic) and two separate analyses were performed on pregnancy rates using a harmonic sinoidal trend based on the synodic and anomalistic lunar cycles respectively. RESULTS: The overall pregnancy rate was 30.9%. The amplitude of harmonic sinoidal, trend for the synodic lunar cycles was chi2 = 1.63,2d.f., p = 0.44 and chi2 = 6.27,2d.f., p = 0.044 for the anomalistic moon periods. For the anomalistic lunar months the amplitude of harmonic sinoidal trend was borderline in terms of higher pregnancy rates with the moon in Perigee. CONCLUSION: The cause of seasonal changes in IVF-ET outcomes is probably very complex. Our results indicate that lunar influence may only be one of the contributing factors. Further studies are needed to clarify unexplained fluctuations of pregnancy outcomes.

Ascorbic acid supplement during luteal phase in IVF.

PURPOSE: To evaluate the impact of ascorbic acid of different doses as additional support during luteal phase in infertility treatment by means of a prospective, randomized, placebo-controlled, group comparative, double-blind study. METHODS: Voluntary daily oral intake of either ascorbic acid (1, 5, or 10 g/day) or Placebo for 14 days after follicle aspiration for IVF-ET procedure. Data was obtained on 620 cases of women, age <40 years, undergoing first IVF-embryo transfer cycles in two private outpatient infertility clinics. All women were stimulated by the same protocol. The mean age was 31.73 (+/- 4.4 SD) years. RESULTS: No differences in clinical pregnancy rate and implantation rate were noted in statistical logistic regression analysis between the four intake groups. CONCLUSIONS: There was no clinical evidence of any beneficial effect, as defined by main outcome measures, of ascorbic acid on IVF-ET. Our data suggest there is no obvious value of high dosed intake of vitamin C during luteal phase in infertility treatment.