It has been observed that mechanical stimulation of the skin of the index fingertip causes a weak short-latency inhibition followed by a strong long-lasting facilitation of the flexor carpi radialis (FCR) H-reflex. Based on threshold and latency, these cutaneous reflexes are thought to be routed to motoneurons by parallel pathways. As recent studies have shown predominant inhibitory potentials in slow motoneurons and predominant excitatory potentials in faster ones, the question arises as to whether or not the two cutaneous pathways converge onto the same motoneuron. The poststimulus time histogram technique was used to investigate the changes in firing frequency of low-threshold FCR motor units (MUs), induced by passive mechanical or focal electrical stimuli to the index skin. After gently tapping the finger pulp a small sharp inhibition appeared in 20 MUs. On average, inhibition started 10.2 +/- 1.6 ms from the homonymous Ia monosynaptic effect, and its central delay was estimated to be 1.2 +/- 1.6 ms. The subsequent facilitation, more consistent, had a mean latency of 13.5 +/- 1.7 ms. Inhibition and excitation were statistically significant (P < 0.05). A similar biphasic effect was observed in seven other FCR-MUs, also after focal electrical stimulation of the same skin area. Comparison with the time course of the H-reflex, representing the whole population of MUs, showed striking similarities in time course and latency to the present MU effect. It is thus suggested that cutaneous spinal pathways may have a homogeneous distribution within the FCR motoneuron pool, and that the skewed distribution of cutaneous afferents onto motoneurons should be not taken as a rule.
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http://dx.doi.org/10.1111/j.1460-9568.2007.05834.x | DOI Listing |
Nano Converg
January 2025
Bendable Electronics and Sustainable Technologies (BEST) Group, Electrical and Computer Engineering Department, Northeastern University, Boston, MA, 02115, USA.
The intriguing way the receptors in biological skin encode the tactile data has inspired the development of electronic skins (e-skin) with brain-inspired or neuromorphic computing. Starting with local (near sensor) data processing, there is an inherent mechanism in play that helps to scale down the data. This is particularly attractive when one considers the huge data produced by large number of sensors expected in a large area e-skin such as the whole-body skin of a robot.
View Article and Find Full Text PDFBMC Oral Health
January 2025
Afrone Network, Faculty of Dentistry, Alexandria University, Alexandria, Egypt.
Background: Climate change is a global challenge, caused by increasing greenhouse gas (GHG) emissions. Dental clinical practice contributes to these emissions through patient and staff travel, waste, energy and water consumption and procurement. Carbon footprinting quantifies GHG emissions.
View Article and Find Full Text PDFEur Arch Otorhinolaryngol
January 2025
Audio-vestibular Medicine unit, department of Ear, Nose and throat, Faculty of Medicine, Assiut University, Assiut, Egypt.
Background: Subjective tinnitus is characterized by perception of sound in the absence of any external or internal acoustic stimuli. Many approaches have been developed over the years to treat tinnitus (medical and nonmedical). However, no consensus has been reached on the optimal therapeutic approach.
View Article and Find Full Text PDFSci Rep
January 2025
College of Veterinary Medicine, Anhui Agricultural University, Hefei, Anhui, China.
Previous studies have confirmed that methylation regulates gene transcription in the hypothalamus-pituitary-gonadal axis during puberty initiation, but little is known about the regulation of DNA methylation on gene expression in the pineal gland. To screen pineal gland candidate genes related to the onset of goat puberty and regulated by genome methylation, we collected pineal glands from prepubertal and pubertal female goats, then, determined the DNA methylation profile by whole genome bisulfite sequencing and the transcriptome by RNA sequencing on Illumina HiSeqTM2500. We analyzed differentially expressed genes between the Pre group and Pub group using the DESeq2 software (version 1.
View Article and Find Full Text PDFNat Commun
January 2025
National-Local Joint Engineering Laboratory of Druggability and New Drug Evaluation, National Engineering Research Center for New Drug and Druggability (cultivation), Guangdong Province Key Laboratory of New Drug Design and Evaluation, School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, 510006, China.
Epitranscriptomic modifications, particularly N6-methyladenosine (mA), are crucial regulators of gene expression, influencing processes such as RNA stability, splicing, and translation. Traditional computational methods for detecting mA from Nanopore direct RNA sequencing (DRS) data are constrained by their reliance on experimentally validated labels, often resulting in the underestimation of modification sites. Here, we introduce pum6a, an innovative attention-based framework that integrates positive and unlabeled multi-instance learning (MIL) to address the challenges of incomplete labeling and missing read-level annotations.
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