scholarly journals Magnetophospenes in humans exposed to ELF MF up to 50 mT, a threshold study

2018 ◽  
Author(s):  
A Legros ◽  
J Modolo ◽  
M Corbacio ◽  
D Goulet ◽  
M Plante ◽  
...  
Keyword(s):  
Flux Density ◽  
Current Knowledge ◽  
Small Sample Size ◽  
Low Frequency ◽  
Small Sample ◽  
Magnetic Flux Density ◽  
Clear Trend ◽  
Total N ◽  
Eeg Data ◽  
Group 2

AbstractAlthough magnetophosphene perception is the most reliable reported effect on acute human neurophysiological responses to extremely low frequency (ELF) magnetic field (MF) exposure, current knowledge is based on small sample size, non-replicated experiments. In this study, we established MF levels triggering magnetophosphenes at 20, 50, 60 and 100 Hz in humans. Magnetophosphene perception and EEG were collected in 55 magnetic flux density conditions randomly delivered in each frequency group (2 experiments, total n=145). Results indicate that threshold values 1) need to be reported as a function of dB/dt instead of flux density, and 2) are frequency-dependent (higher sensitivity to lower frequencies). No clear trend was found in EEG data.

scholarly journals Biological Effects of a Low-Frequency Electromagnetic Field on Yeast Cells of the Genus Saccharomyces Cerevisiae

2021 ◽  
Vol 21 (2) ◽  
pp. 34-41
Author(s):  
K Sladicekova ◽  
M Bereta ◽  
J Misek ◽  
D Parizek ◽  
J Jakus
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Electromagnetic Field ◽  
Magnetic Flux ◽  
Flux Density ◽  
Biological Effects ◽  
Low Frequency ◽  
Growth Dynamics ◽  
Yeast Cells ◽  
Magnetic Flux Density ◽  
Time Points

Abstract Background: Although the scientific community is extensively concerned with the effects of the EMF, the unambiguous explanation of its effects on living structures is still lacking. Goals: The goal of the study was to evaluate the effect of a low-frequency (LF) electromagnetic field (EMF) on the growth and multiplication of the yeast Saccharomyces cerevisiae. Methods: Yeast cells were exposed to a frequency of 900 Hz and a magnetic flux density of 2.3 mT. The duration of each experiment was 8 hours, in the beginning of the measurement the value of frequency, rms (root mean square) value of electric current (2 A), and magnetic flux density were fixed set on the exposure device. A paired experiment was performed, a sample exposed to EMF, and a sample shielded from the field. Subsequently, samples were taken every two hours, the number of cells was recorded, and then the concentration of the yeast cells was evaluated at time points. The time points reflected the exposure time of the samples exposed to EMF. Results: The results indicate that LF EMF at given parameters has an inhibitory effect on the growth and multiplication of yeast cells. Conclusion: Exposure to EMF can cause the differences in growth dynamics between cells exposed to the field and the unexposed ones.

P–383 Cytogenetic analysis of products of conception from miscarriages following natural conception and IVF pregnancy: a comparative study

2021 ◽  
Vol 36 (Supplement_1) ◽  
Author(s):  
F Kaderbhai ◽  
E Kalu ◽  
P Chan
Keyword(s):  
Cytogenetic Analysis ◽  
Small Sample Size ◽  
Chromosomal Rearrangements ◽  
Small Sample ◽  
Assisted Conception ◽  
Total N ◽  
Recurrent Miscarriages ◽  
Products Of Conception ◽  
Cytogenetic Testing ◽  
Natural Conception

Abstract Study question Do cytogenetic results from products of conception from miscarriages differ from patients conceiving by natural conception versus IVF? Summary answer: Cytogenetic results were similar, with no statistical difference from miscarriages following natural conception and assisted conception. What is known already Cytogenetic sampling of products of conception (POC) following recurrent miscarriages (RM) are recommended to rule out parental chromosomal rearrangements. The RCOG recommends cytogenetic testing in cases of recurrent miscarriages (3 consecutive miscarriages). However some units routinely request cytogenetic analysis following a single miscarriage following an IVF pregnancy. There is no evidence to support the routine sampling of POCs following assisted conception. Study design, size, duration: Retrospective cohort study of 117 cytogenetic samples, followed up by the outcome of parental karyotyping if applicable. Patients were categorised based on mode of conception into natural conception (NC) with recurrent miscarriages (≥3) or one miscarriage following IVF. Data collected between 2018–2020. Primary Outcome measure: Presence and type of cytogenetic abnormality; individual parental targeted G-band karyotyping result. Participants/materials, setting, methods: A total of 117 cytogenetic results were reviewed, of which 35 were unsuitable for analysis due to contamination (Total n = 79: NC = 60, IVF = 19). Main results and the role of chance: Cytogenetic analysis showed abnormal results in 59% of miscarriages following natural conception and 53% of miscarriages from IVF pregnancy (p = 0.46). Abnormal cytogenetic results were mainly sporadic. Trisomy 16 was the commonest abnormality in both groups. Others included Trisomy 15, 22, 21, 8, 13, 5, 9, 10, 14, 18, single X (Turner’s), all occurring in the same frequency in both groups. As expected 35 out of 45 abnormal cytogenetic results occurred with a maternal age greater than 35 years. One couple from the NC group were referred to a geneticist for a Trisomy 9 imbalance. All other parental karyotyping results were normal. Limitations, reasons for caution This study contains a small sample size, and would benefit from further data collection to account for a percentage of samples being inadequate for analysis. Wider implications of the findings: Cytogenetic results were similar from miscarriages following natural conception and assisted conception. IVF does not increase the risk of miscarriage from abnormal embryonic karyotype. Routine cytogenetic testing following one miscarriage in patients undergoing IVF is not cost effective. Trial registration number Not applicable

scholarly journals Effects of the Dietary Approaches to Stop Hypertension Diet and Sodium Reduction on Blood Pressure in Persons With Diabetes

Hypertension ◽  
2020 ◽  
Author(s):  
Eva Tseng ◽  
Lawrence J. Appel ◽  
Hsien-Chieh Yeh ◽  
Scott J. Pilla ◽  
Edgar R. Miller ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Dietary Pattern ◽  
Behavioral Interventions ◽  
Small Sample Size ◽  
Small Sample ◽  
Dietary Sodium ◽  
Sodium Reduction ◽  
Dietary Interventions ◽  
Total N ◽  
Intervention Delivery

Elevated blood pressure and blood pressure-related morbidity are extraordinarily common in persons with diabetes. The Dietary Approaches to Stop Hypertension dietary pattern and dietary sodium reduction are recommended as lifestyle interventions in individuals with diabetes. However, these recommendations have largely been based on studies conducted in persons without diabetes. In this review, we summarize available evidence from trials that tested the effects of these 2 dietary interventions on blood pressure in people with diabetes. Overall, of the 3 trials (total n=151) that tested the effects of the Dietary Approaches to Stop Hypertension dietary pattern in persons with diabetes, 2 trials documented that the Dietary Approaches to Stop Hypertension dietary pattern lowered blood pressure. While 16 trials (total n=445) tested the effects of sodium reduction in persons with diabetes, results were inconsistent, likely because of design limitations, for example, brief duration, small sample size, and low baseline blood pressure levels, as well as differences in the mode of intervention delivery (behavioral interventions, feeding studies, and sodium supplements). In conclusion, there is a substantial need for additional research on the blood pressure lowering effects of the Dietary Approaches to Stop Hypertension diet and sodium reduction in people with diabetes and hypertension, given the high prevalence of hypertension and the dearth of high-quality trials in this population.

How Long does it Take for Antidepressant Therapies to Act?

2000 ◽  
Vol 34 (1) ◽  
pp. 65-70 ◽  
Author(s):  
Gordon Parker ◽  
Kay Roy ◽  
David B. Menkes ◽  
John Snowdon ◽  
Philip Boyce ◽  
...  
Keyword(s):  
Small Sample Size ◽  
Strong Predictor ◽  
Antidepressant Drugs ◽  
Longitudinal Component ◽  
Small Sample ◽  
Depression And Anxiety ◽  
Onset Of Action ◽  
Clear Trend ◽  
Early Improvement ◽  
Delayed Onset

Objective: To review the proposition that antidepressants have a delayed onset of action by employing measurement and analytic strategies that overcome problems confounding interpretation of many efficacy studies. Method: A subset of patients was recruited to the longitudinal component of the Australasian database study, was assessed at baseline, and then completed measures of depression and anxiety when treatment commenced, and every 3 days over the next 4 weeks. The trajectories of defined 4-week outcome responders and non-responders were compared. Results: Both groups showed a similar decrease in depression (and anxiety) over the first 3 days. A clear trend break then occurred, with little further improvement in the non-responders, as against distinct and progressive improvement in the responders. Ongoing early improvement (across days 3–6) was a strong predictor of responder status. Conclusions: The small sample size limits firm interpretation, although distinct interpretive advantages to the study design are evident. Findings are compatible with a number of recent studies arguing against any extensive delayed onset of action for the antidepressant drugs, but argue for caution in interpreting immediate improvement as predicting likely responder status, and more for examining early and sustained improvement as such a marker.

A fistful of shells: amplifying sclerochronological and palaeoclimate signals from molluscan death assemblages

2009 ◽  
Vol 146 (6) ◽  
pp. 917-930 ◽  
Author(s):  
S. HELAMA ◽  
J. K. NIELSEN ◽  
M. MACIAS FAURIA ◽  
I. VALOVIRTA
Keyword(s):  
Sample Size ◽  
Tree Ring ◽  
Small Sample Size ◽  
Low Frequency ◽  
Small Sample ◽  
Pearl Mussel ◽  
Climate Signal ◽  
Growth Variability ◽  
Low Frequency Variability ◽  
The Individual

AbstractA growing body of literature is using sclerochronological information to infer past climates. Sclerochronologies are based on series of skeletal growth records of molluscs that have been correctly aligned in time. Incremental series are obtained from a number of shells to assess the temporal control and improve the climate signal in the final chronology. Much of the sclerochronological theory has been adopted from tree-ring science, due to the longer tradition and more firmly established concepts of chronology construction in dendrochronology. Compared to tree-ring studies, however, sclerochronological datasets are often characterized by relatively small sample size. Here we evaluate how effectively palaeoclimatic signal can be extracted from such a suite of samples. In so doing, the influences of the very basic methods that are applied in nearly every sclerochronological study to remove the non-climatic growth variability prior to palaeoclimatic interpretations, are ranked by their capability to amplify the desired signal. The study is performed in the context of six shells that constitute a bicentennial growth record from annual shell increments of freshwater pearl mussel. It was shown that when the individual series were detrended using the models set by the mean or the median summary curves for ageing (that is, applying Regional Curve Standardization, RCS), instead of fitting the ageing mode statistically to each series, the resulting sclerochronology displayed more low-frequency variability. Consistently, the added low-frequency variability evoked higher proxy–climate correlations. These results show the particular benefit of using the RCS method to develop sclerochronologies and preserve their low-frequency variations. Moreover, calculating the ageing curve and the final chronology by median, instead of mean, resulted in an amplified low-frequency climate signal. The results help to answer a growing need to better understand the behaviour of the sclerochronological data. In addition, we discuss the pitfalls that may potentially disrupt palaeoclimate signal detection in similar sclerochronological studies. Pitfalls may arise from shell taphonomy, water chemistry, time-variant characters of biological growth trends and small sample size.

CD14 and Tissue Factor Positive Extracellular Vesicles Predict Response to Dovitinib in Patients with GBM: A Pilot Study

Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 4999-4999
Author(s):  
Nikolaos Papadantonakis ◽  
Manmeet S Ahluwalia ◽  
Micheal Khoury ◽  
Shruti Chaturvedi ◽  
Keith R. McCrae
Keyword(s):  
Growth Factor ◽  
Sample Size ◽  
Progressive Disease ◽  
Small Sample Size ◽  
Small Sample ◽  
Malignant Cells ◽  
Angiogenic Therapy ◽  
Pre Treatment ◽  
Group 2 ◽  
Group 1

Abstract BACKGROUND: Glioblastoma (GBM) is most common primary malignant brain tumor, and has a median survival of 15-18 months. Dovitinib, an oral multi-tyrosine kinase inhibitor of vascular endothelial growth factor (VEGF), fibroblast growth factor (FGF), and platelet derived growth factor (PDGF) is currently under study in a phase II trial for GBM at the Cleveland Clinic. Dovitinib is administrated 5 days on and 2 days off every 4 weeks until progressive disease (PD) or intolerable toxicity are observed. Extracellular vesicles (EV) are submicron particles that express or contain cellular proteins and nucleic acids and are released from a variety of non-malignant cells (e.g. endothelial cells, platelets, leucocytes) and malignant cells. In some settings, EV may serve as biomarkers of inflammation, thrombosis and tumor spread/burden. OBJECTIVE: The aim of our study was to characterize levels of circulating EV and their relation to disease course in patients with GBM enrolled in the Dovitinib study (with or without prior treatments with anti-angiogenic agents). We also examined the association between EV levels and the development of venous thromboembolism (VTE). METHODS: Patients previously treated with anti-angiogenic therapy (Group 1, n=14) or without prior anti-angiogenic treatment (Group 2, n=14) were examined separately. EV were measured at study enrollment (pre-treatment), at the end of cycle 1 (day 28), and at PD. EV were isolated from citrated whole blood by differential centrifugation and incubated with fluorochrome-conjugated monoclonal antibodies to CD144-PE (endothelial cells), CD41-PECy4 (platelets), CD14-PE (monocytes) and CD142 (tissue factor, Alexa Fuor 647), then analyzed by flow cytometry. Depending on sample size, the Student t-test or Wilcoxon test was used to compare EV levels (due to the small sample size and skewed distribution of EV levels). P<0.05 was considered significant for all analyses. RESULTS: Three patients from group 1 and 6 patients from group 2 were not included in the analysis secondary to lack of an EV sample, withdrawal of consent or complications leading to early drug discontinuation. Of theremaining 11 patients in Group 1, 3 had PD and 8 had stable disease (SD) at the end of cycle 1. Of the 8 patients in group 2 available for analyses after cycle 1, 2 had PD and 6 had SD (one of these developed VTE but continued on the study). In the pretreatment sample of patients from group 1, patients who developed PD had significantly higher levels of CD14+ EV (89977±12121 vs. 42237±27651, p =0.048) and CD142+ EV (68701±9010 vs. 9695±12462, p=0.048) compared to those with SD. However, there was no statistically significant difference in EV levels (all sub-populations) from pre-treatment to the end of cycle 1 in patents with either PD or SD. EV levels did not correlate with peripheral blood counts. Due to the small number of patients in group 2 with progressive disease, we were unable to assess the correlation with EV. Six (2 in group 1, 4 in group 2) of the 27 patients for which pre-treatment EV were available developed VTE during the study. The EV levels were not significantly different between patients who developed VTE compared to those who did not both at pretreatment and at the day 28 evaluation. However, most patients who developed VTE demonstrated profound increases in EV before or in association with their thrombotic event. CONCLUSIONS: In patients with GBM receiving Dovitinib without prior exposure to anti-angiogenic therapy, elevated pre-treatment levels of CD14+ and CD142+ EV were associated with progressive disease, suggesting their potential role as a predictor of poor response to Dovitinib. Due to the relatively small sample size, no significant differences were observed between patients that developed VTE and those that did not, either pretreatment or at the Day 28 evaluation; however, these studies are ongoing. In the majority of patients with VTE, EV levels increased substantially before or in association with VTE development. Acknowledgment: This work was supported by a grant from the Scott Hamilton Cares Initiative Disclosures No relevant conflicts of interest to declare.

scholarly journals Microsurgical resection of brain arteriovenous malformations in the elderly: outcomes analysis and risk stratification

2018 ◽  
Vol 129 (5) ◽  
pp. 1107-1113 ◽  
Author(s):  
Jan-Karl Burkhardt ◽  
George F. Lasker ◽  
Ethan A. Winkler ◽  
Helen Kim ◽  
Michael T. Lawton
Keyword(s):  
Elderly Patients ◽  
Arteriovenous Malformations ◽  
Small Sample Size ◽  
Functional Dependence ◽  
The Elderly ◽  
Small Sample ◽  
Treatment Modalities ◽  
Total N ◽  
Microsurgical Resection

OBJECTIVEFew outcomes studies have been published on microsurgical resection of arteriovenous malformations (AVMs) in elderly patients, and most are limited by a small sample size and the heterogeneous application of treatment modalities. This study aimed to determine whether functional outcomes at last follow-up (LFU) in patients 60 years or older differed when stratified by age.METHODSPatients 60 years or older (n = 104) who had undergone microsurgical AVM resection (total, n = 72; 60–65 years, n = 35; and > 65 years, n = 37) or observation (n = 32) were identified from a prospective database. Age, sex, Spetzler-Martin (SM) grade, supplemented SM grade, clinical presentation, AVM location, AVM-associated aneurysms, and functional outcome measured using the modified Rankin Scale (mRS score 0–2 [favorable] vs mRS score > 2 [unfavorable]) at LFU were analyzed.RESULTSAVM patients undergoing microsurgical resection were younger, had lower AVM grades, and were more likely to present with rupture. Overall outcome in the surgical group was favorable in 71% of the patients and was statistically significantly better in patients 60–65 years old (p = 0.039). In patients older than 65 years, outcome was dependent on SM grade and level of preexisting functional dependence. Patients with supplemented SM grades of greater than 6 points had favorable outcomes that were age dependent (p = 0.029). This difference was not observed in patients with lower supplemented SM grades or in those with low or high preoperative SM grades (SM grade ≤ 2 and grade ≥ 4, respectively).CONCLUSIONSThis study demonstrates that favorable outcomes can be achieved with microsurgical resection of AVMs in elderly patients, with careful patient selection. Outcomes in more elderly patients (> 65 years of age) are more dependent on preoperative SM and supplemented SM grading than those in younger cohorts.

scholarly journals Assessment of advice to reduce dietary fat and non-milk extrinsic sugar in a free-living male population

1999 ◽  
Vol 2 (2) ◽  
pp. 187-197 ◽  
Author(s):  
Sandra Drummond ◽  
Terry Kirk
Keyword(s):  
Energy Intake ◽  
Dietary Fat ◽  
Small Sample Size ◽  
Small Sample ◽  
Dietary Advice ◽  
Control Group ◽  
Free Living ◽  
Initial Decrease ◽  
Group 2 ◽  
Group 1

AbstractObjectiveTo compare the effect of advice to reduce both dietary fat and sugar with advice to reduce fat alone on subsequent dietary intake in Scottish men.DesignA parallel design intervention study was employed to measure compliance to the two types of dietary advice. Subjects were randomly assigned to Group 1 (advice to reduce fat and non-milk extrinsic (NME) sugar), Group 2 (advice to reduce fat only, ad libitum sugar) or a control Group 0 (no advice). Compliance was assessed by two 4-day food diaries over 6 months.SettingThe study was conducted in the Strathclyde area of Scotland.SubjectsSubjects were normal to moderately overweight Scottish men. The men recruited were non-dieting and volunteered for a ‘healthy eating’ study with the aim to improve the ‘healthiness’ of their diet.ResultsGroups 1 and 2 achieved the dietary target for fat, reducing their mean intake to below 35% energy. Group 1 achieved a statistically significant reduction in percentage energy from NME sugar in the short term (6 weeks), decreasing their mean intake from 9.9% to 7.2% energy. This initial decrease appeared to slip back towards baseline levels at 6 months (8.1% energy from NME sugar) and was no longer significantly different from baseline. At 6 months Group 1 reported a significantly lower mean energy intake than at baseline, whereas Group 2 adjusted for an initial decrease in energy intake and by 6 months energy intakes were not significantly different from baseline intakes. Group 2 appeared to compensate for the absolute reduction in dietary fat with a slight increase in total sugars and the maintenance of NME sugar intakes.ConclusionsSubjects in Group 1 complied with advice to reduce both fat and sugar over 6 weeks but to a lesser extent over 6 months. The 1.8% reduction in percentage energy from NME sugars in Group 1 at 6 months may not have reached significance due to the small sample size. Alternatively it may be that free-living populations find it hard to maintain concurrent reductions in fat and sugar owing to the well-documented inverse relationship between intakes of these macronutrients when expressed as a proportion of energy.

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