Search results for "STIMULATION"

Induction of (2′−5′)oligoadenylate synthetase in the marine spongesSuberites domunculaandGeodia cydoniumby the bacterial endotoxin lipopolysaccharide

2002

Recent studies have shown that the Porifera, with the examples of the demosponges Suberites domuncula and Geodia cydonium, comprise a series of pathways found also in the immune system of Deuterostomia, such as vertebrates, but are absent in Protostomia, with insects or nematodes as examples. One pathway is the (2'-5')oligoadenylate synthetase [(2-5)A synthetase] system. In the present study we show that crude extracts from tissue of S. domuncula collected from the sea display a considerable amount of (2-5)A synthetase activity; 16% of the ATP substrate is converted to the (2-5)A product, while tissue from specimens which were kept for 6 months in an aquarium shows only 1% of conversion. As…

Release of Inflammatory Mediators (PGE2, IL-6) by Fenofibric Acid-Photosensitized Human Keratinocytes and Fibroblasts

1998

Ultraviolet-A radiation has weak effects on the release of inflammatory mediators by skin cells due to the poor overlap between UVA wavelengths and the absorption spectra of the relevant chromophores of key biomole-cules. However, this situation could be very different in the presence of a photosensitizing drug. To investigate this issue, we have irradiated human skin cells (keratinocytes and fibroblasts) in the presence of fenofibric acid (the active phototoxic metabolite of fenofibrate). The results of this research show a dual effect on the production/release of inflammatory mediators: the synthesis of the proinflammatory cytokine interleukin-6 becomes strongly inhibited at photosensitiz…

TRANSPLANTATION AND IN VITRO ANALYSIS OF SOYBEAN-AGGLUTININ SEPARATED MOUSE SPLEEN CELLS

1984

In human bone marrow allotransplantation, an in vitro method using soybean agglutinin(SBA) for enrichment of stem cells and depletion of mature T cells in the graft has been described (Reisner et al.;Lancet 2:1320,1980).To define the quality of the method,mouse spleen cells (C3H, C57/B6,BALB/c)containing about 30% of mature T cells were separated by SBA.The composition and functional capacity of the cell fraction known to contain the stem cells were characterized in vitro after each of two SBA-separation steps.In addition, the ability of the cell fraction to reconstitute successfully allogeneic irradiated (900R) mice was investigated. Only the two step SBA-separation procedure yielded satis…

Extremely Low Frequency Magnetic Fields Do Not Affect LTP-Like Plasticity in Healthy Humans.

2020

Introduction: Several studies explored, in vitro, the biological effects of extremely low-frequency magnetic fields (ELF-MFs) and reported the induction of functional changes in neuronal activity. In particular, ELF-MFs can influence synaptic plasticity both in-vitro and in animal models. Indeed, some studies reported an increase in long-term potentiation (LTP) whereas others suggested its reduction. However, no specific study has investigated such effect in humans. Aims: To evaluate whether ELF-MFs affect the propensity of the human cortex to undergo LTP-like plasticity. Methods: We designed a randomized, single-blind, sham-controlled, cross-over study on 10 healthy subjects. Cortical plas…

Development of new strategies to assess the safety of controlled ovarian stimulation for fertility preservation in breast cancer patients

2023

El càncer de mama és la neoplàsia més comuna en dones en edat reproductiva. Les millores en el diagnòstic i el tractament d'aquesta malaltia han suposat un important descens en la mortalitat en els darrers 20 anys. Tot i això, el tractament quimioterapèutic del càncer de mama resulta altament gonadotòxic, sovint danyant la funció ovàrica i implicant una pèrdua de la fertilitat posterior. Per aquest motiu, oferir la possibilitat de preservar la fertilitat en dones amb desitjos reproductius posteriors resulta de vital importància. Entre les opcions per preservar la fertilitat femenina, la criopreservació d'ovòcits i/o embrions destaca com la tècnica amb més èxit a la pràctica clínica habitual…

Toll-like receptors play a crucial part in the pathophysiological activity of antiphospholipid antibodies

2011

The antiphospholipid syndrome (APS) is a systemic autoimmune disease characterized by thrombosis, recurrent fetal loss and the presence of a variety of antiphospholipid antibodies (aPL), directed to phospholipids like Cardiolipin and phospholipid binding proteins like β2-glycoprotein I. Till date, the pathophysiological processes underlying these thrombotic events were still not fully understood. Recent data support the idea that the aPL might act via enhanced cytokine release due to activation of certain Toll-like receptors. The investigation of some of those mechanisms in more detail enlightens the involvement of the intracellular receptors TLR7 and TLR8 in a central point. Using patients…

Muscle-Monitoring Textiles: Cutaneous Recording and Stimulation of Muscles Using Organic Electronic Textiles (Adv. Healthcare Mater. 16/2016)

2016

Psychophysical response to electrocutaneous stimulation.

1984

A method is presented to determine a reliable stimulus-sensation relationship particularly suitable for electrocutaneous stimulation. An experimental intensity-discrimination curve was obtained through simple psychophysical comparison tasks, and sensory response was inferred from integration of a JND's density function. The psychophysical response resembles a power law, although departures cannot be described in terms of a unique exponent. An estimate of binary information capacity per electrode is also given as a feature of a stimulation procedure that preserves a low value of the size-intensity product.

The Effect of Medium-Intensity Electromagnetic Stimulation on Pelvic Floor Muscle Activity in a Young Woman—A Case Report

2021

Aims In recent years, devices for deep electromagnetic stimulation have been implemented in clinical practice. These devices generate pulses with a frequency of 1 to 50 Hz and magnetic induction of up to 2.5 T. Due to the possibility of producing or an effective deep-penetrating mechanical vibration, electromagnetic stimulation is increasingly used in the physiotherapy of urogynecological disorders. This study aimed to analyse of the effect of deep electromagnetic stimulation on the bioelectrical activity of pelvic floor muscles in a young woman. Case report The case of a 24-year-old woman with no diagnosed stress urinary incontinence is presented. The subject underwent electromagnetic stim…

P–446 Controlled ovarian stimulation protocols for oocyte vitrification induce differential gene expression profiles in primary tumours of breast can…

2021

Abstract Study question Could controlled ovarian stimulation (COS) protocols used in fertility preservation (FP) impact on malignant cell proliferation and tumour molecular profiling of breast cancer (BC) patients? Summary answer Letrozole supplementation during ovarian stimulation for oocyte vitrification could be considered as a safe procedure in estrogen-dependent BC patients undergoing FP. What is known already High estradiol levels associated to COS could promote changes in gene expression in estrogen-positive BC tumors. Estradiol levels reached during the ovarian stimulation could aggressively promote malignant cell proliferation and cell migration to adjacent organs. Aromatase inhibi…