stimulation protocol
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2021 ◽  
Author(s):  
Jonna Leppänen ◽  
Petrus Nuotio ◽  
Kaisa Randell ◽  
Jarkko Romppanen ◽  
Leea Keski-Nisula ◽  
...  

Abstract Background: Do different hormonal phases affect appetite regulation, food intake, and concentrations of leptin, glucagon-like peptide-1 (GLP-1), and high-sensitivity C-reactive protein (hs-CRP) during a long agonist in vitro fertilization (IVF) protocol? Does the IVF stimulation induce metabolic changes, which might impact maternal health? Methods: Fifty-four infertile women were encountered thrice, the first of which was at the beginning of their period (low estradiol). The other two were during a gonadotrophin-releasing hormone (GnRH) analog downregulation (low estradiol) and at the end of a follicle-stimulating hormone (FSH) stimulation (high estradiol). The first visit was the reference; the women served as their controls. The concentrations of leptin, GLP-1, and hs-CRP were assessed from plasma. Dietary intake was assessed using food records (FRs) three days before each visit. In addition, weight, height, body mass index (BMI), and plasma levels of estradiol, glucose, HbA1c, insulin, and lipids were monitored. Twenty-six of the subjects also had a postprandial test, in which the blood samples were taken at five time points at every three visits. They also filled visual analog scales to exhibit satiety and appetite. Twenty-eight of the subjects had only fasting blood samples. Results: During the stimulation protocol, leptin concentrations elevated (P<0.001), and energy intake decreased (P=0.03) while estradiol levels increased (P<0.001). GLP-1 levels unchanged (P=0.75) and hs-CRP (P=0.03) concentrations diminished while estradiol levels increased. Conclusions: No increased food intake or weight gain occurred during the stimulation protocol; thus, leptin may protect from overeating during high estradiol levels, and leptin resistance may not occur during a short follow-up. Also, a favorable anti-inflammatory effect was detected. During this study, no harmful metabolic effects occurred, which might have a disproportionate impact on maternal health. Trial registration: Not applicable. This study is a clinical study without intervention.


Molecules ◽  
2021 ◽  
Vol 27 (1) ◽  
pp. 138
Author(s):  
Xesús Feás ◽  
Carmen Vidal ◽  
M. Pilar Vázquez-Tato ◽  
Julio A. Seijas

The yellow-legged Asian hornet (Vespa velutina Lepeletier 1836 (Hymenoptera: Vespidae)) is naturally distributed in China, Southeast Asia, and India; however, recently it has been detected outside of its native area, confirmed as being established in South Korea, Europe, and Japan. Health risks and deaths caused by the invasive Vespa velutina stings have become a public health concern, being the most common cause of anaphylaxis due to hymenopterans in some European regions. This in turn has led to increased demand from medical practitioners and researchers for Vespa velutina venom for diagnostic and therapeutic purposes. In this study, a straightforward, quick, and inexpensive method for obtaining Vespa velutina venom by electric stimulation is described. The venom extracts were analyzed by nuclear magnetic resonance spectroscopy (1H-NMR). The availability of Vespa velutina venom will lead to improved diagnostic and therapeutic methods, mainly by venom immunotherapy (VIT), in patients allergic to this invasive species.


Author(s):  
Marc-André Sirard

Abstract In human IVF, the main uncertainty factor impacting on success is oocyte quality, which largely depends on the follicular status at the time of collection. Decades of debate ensued to find the perfect stimulation protocol demonstrated the complexity of the ovarian response to exogenous gonadotropins and the dynamic nature of late folliculogenesis. Although several follicular markers, proteins, RNA from granulosa cells or microRNA and follicular fluid metabolites have been associated with outcome, the possibility to influence them during stimulation remains elusive. The heterogeneity of the follicle’s maturity following control ovarian stimulation is also an important factor to explain average poor oocyte quality still observed today. In this review, the analogy between the apple ripening on the tree and follicular development is presented to focus the attention on a biphasic process: growth and differentiation. The molecular analysis of the progressive follicular differentiation indicates 2 competing phenomena: growth and differentiation where a delicate balance must operate from one to the other to ensure proper maturity at ovulation. As long as FSH stimulates growth, follicles remain green, and it is only when FSH is replaced by LH that the ripening process begins, and “apples” become red. Both fruits, follicles and apples, depend on a perfect timing of events to generate offspring.


2021 ◽  
Author(s):  
Hong Chen ◽  
Zhi qin Chen ◽  
Ernest Hung Yu Ng ◽  
zili sun ◽  
Zheng wang ◽  
...  

Abstract Background: The efficacy and reproductive outcomes of progestin primed ovarian stimulation protocol (PPOS) were previously compared to rarely used ovarian stimulation protocol and also the live birth rate were reported by per embryo transfer rather than cumulative live birth rates (CLBRs). Does the use of PPOS improve the cumulative live birth rates (CLBRs) and shorten time to live birth when compared to long GnRH agonist protocol in women with normal ovarian reserve?Methods: A retrospective cohort study was designed to include women aged<40 with normal ovarian reserve (regular menstrual cycles, FSH <10 IU/L, antral follicle count >5) undergoing IVF from January 2017 to December 2019. The primary outcome was cumulative live birth rates (CLBRs) within 18 months from the day of ovarian stimulation.Results: A total of 995 patients were analyzed. They used either PPOS (n=509) or long GnRH agonist (n=486) protocol at the discretion of the attending physicians. Both groups had almost comparable demographic and cycle stimulation characteristics except for duration of infertility which was shorter in the PPOS group. In the GnRH agonist group 372 cases (77%) completed fresh embryo transfer, resulting into 218 clinical pregnancies and 179 live birth. The clinical pregnancy rate, ongoing pregnancy, and live birth per transfer were 58.6%, 54.0%, 53.0% respectively. In the PPOS, no fresh transfer was carried out. During the study period, the total number of initiated FET cycles with thawed embryos was 665 in the PPOS group and 259 in the long agonist group. Of all FET cycles, a total of 206/662 (31.1%) cycles resulted in a live birth in the PPOS group versus 110/257 (42.8%) in the long agonist group (OR: 0.727; 95% CI: 0.607–0.871; p<0.001) .The implantation rate of total FET cycles was also lower in the PPOS group compared with that in the agonist group 293/1004 (29.2%) and 157/455 (34.5%) (OR: 0.846; 95% CI: 0.721–0.992; p= 0.041). Cumulative live birth rates after one complete IVF cycle including fresh and subsequent frozen embryo cycles within 18 months follow up were significantly lower in the PPOS group compared that in the long agonist group 206/509 (40.5%) and 307/486 (63.2%), respectively (OR: 0.641; 95% CI: 0.565-0.726). The average time from ovarian stimulation to pregnancy and live birth was significantly shorter in the long agonist group compared to the PPOS group (p<0.01) In Kaplan-Meier analysis, the cumulative incidence of ongoing pregnancy leading to live birth was significantly higher in the long agonist compared in the PPOS group(Log rank test, p<0.001). Cox regression analysis revealed stimulation protocol adopted was strongly associated with the cumulative live birth rate after adjusting other confounding factors (OR =1.917 (1.152-3.190), p=0.012) .Conclusion: Progestin primed ovarian stimulation was associated with a lower cumulative live birth rates and a longer time to pregnancy / live birth than the long agonist protocol in women with a normal ovarian reserve.


2021 ◽  
Vol 50 (1) ◽  
pp. 787-787
Author(s):  
Kyle Brandenberger ◽  
Elliott Scranton ◽  
Richard Sola ◽  
Juan Banda ◽  
Rondi Gelbard ◽  
...  

2021 ◽  
Vol 11 (12) ◽  
pp. 1640
Author(s):  
Katarina Hosel ◽  
François Tremblay

Theta-burst stimulation (TBS) is a form of repetitive transcranial magnetic stimulation (rTMS) developed to induce neuroplasticity. TBS usually consists of 50 Hz bursts at 5 Hz intervals. It can facilitate motor evoked potentials (MEPs) when applied intermittently, although this effect can vary between individuals. Here, we sought to determine whether a modified version of intermittent TBS (iTBS) consisting of 30 Hz bursts repeated at 6 Hz intervals would lead to lasting MEP facilitation. We also investigated whether recruitment of early and late indirect waves (I-waves) would predict individual responses to 30 Hz iTBS. Participants (n = 19) underwent single-pulse TMS to assess MEP amplitude at baseline and variations in MEP latency in response to anterior-posterior, posterior-anterior, and latero-medial stimulation. Then, 30 Hz iTBS was administered, and MEP amplitude was reassessed at 5-, 20- and 45-min. Post iTBS, most participants (13/19) exhibited MEP facilitation, with significant effects detected at 20- and 45-min. Contrary to previous evidence, recruitment of early I-waves predicted facilitation to 30 Hz iTBS. These observations suggest that 30 Hz/6 Hz iTBS is effective in inducing lasting facilitation in corticospinal excitability and may offer an alternative to the standard 50 Hz/5 Hz protocol.


2021 ◽  
Vol 2 (4) ◽  
pp. 100944
Author(s):  
Tianzhen Chen ◽  
Hang Su ◽  
Ruihua Li ◽  
Haifeng Jiang ◽  
Xiaotong Li ◽  
...  

2021 ◽  
Author(s):  
Katharina Brech ◽  
Elena K. Enax-Krumova ◽  
Lynn Eitner ◽  
Jan Vollert ◽  
Christoph Maier ◽  
...  

Abstract Objective: Pain-related evoked potentials (PREP) are increasingly used to investigate nociception and small-fibre function. Due to lack of a standard stimulation protocol, it is unclear whether results from studies using different protocols are comparable. Aim of the study was to assess the influence of different stimulation parameters on N1P1-amplitudes, N1-latencies and PREP-induced pain intensity. Methods: In a cross-over design we examined 31 healthy volunteers using four different stimulation protocols (number of stimulation electrodes 1 vs. 3, stimulus durations 200 µs vs. 500 µs) in a randomized order. Statistics: paired t-test, ANOVA, correlation analyses. Results: Longer stimulus duration induced higher N1P1-amplitudes (p<0.05) and higher pain intensity (p<0.001). Stimulation with 3 electrodes lead to a lower pain intensity (p<0.01), whereas the N1P1-amplitude and stimulus intensity at twofold of individual pain remained unaffected by the number of electrodes. Also, there was no relation between stimulus intensities and N1P1-amplitudes (one electrode: r=0.079; p=0.646, three electrodes: r=-0.10, p=0.70) was observed. N1-latencies remained comparable between the four protocols.Conclusions and Significance: The use of different stimulation protocols for PREP is limited by relevant differences in the N1P1-amplitudes and evoked pain intensities. Standard consented stimulation protocols are needed to allow data comparison between different labs and studies.


2021 ◽  
Vol 9 (5) ◽  
pp. 01-07
Author(s):  
Sheila Veronese ◽  
Marco Cambiaghi ◽  
Andrea Sbarbati

Background: Surgery for applying the auditory brainstem implant is an otoneurosurgery that requires careful intraoperative monitoring to optimize the placement of the electrode paddle. This study aimed to validate a new method capable of increasing the accuracy of electrode array placement, reducing channel interaction, electrical artefacts, and saturation effects, and providing the largest number of electrodes that can be activated with the lowest possible electric charge. Materials and methods: Thirty-six subjects aged between 1.42 and 69.92 years were tested during surgery for auditory brainstem implantation. We recorded auditory electrical responses of the brainstem using the implant supplier's suggested stimulation protocol and the new protocol. Results: Saturations effects and electric artefacts were noticed respectively in 81.85% and 53.25% of recordings using implant supplier's method, while in 70.34% and 24.75% of recordings using the new method, with a percentage variation of 11.51% and 28.50%. Considering the amount of charge required to activate the electrodes, with the implant supplier's method an average charge of 14 nC was needed, while with the new protocol an average charge of 8 nC was necessary. Conclusions: The new method improves the coupling between the auditory brainstem implant and the surface of the cochlear nucleus.


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