Among the hypotheses regarding fusimotor functions based on earlier animal experiments some are inconsistent, others are in conformity with microneurographic observations in man. The human data provide evidence against the following two theories: (1) the length follow-up servo theory; and (2) the theory that fusimotor neurons can be selectively activated to produce spindle sensitization and stretch reflex reinforcements. The human data support the theory of alpha-gamma coactivation. In particular, in the early phase of isometric voluntary contractions fusimotor-driven afferent spindle activity assists in autogenetic activation of alpha motoneurons and in reciprocal relaxation of antagonists. As muscle fatigue develops, the autogenetic reflex drive via the fusimotor route declines. The fusimotor bias during contraction provides for maintenance of spindle sensitivity to minute perturbations and for load-compensating reflex adjustments to such perturbations. Reflex overcorrections may lead to uncontrollable oscillations of the type seen in enhanced physiological tremor.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1002/mus.880160702 | DOI Listing |
CNS Drugs
January 2025
School of Medicine and Dentistry, Gold Coast Campus, Griffith University, Southport, QLD, 4222, Australia.
Background: Epstein-Barr virus (EBV) is implicated as a necessary factor in the development of multiple sclerosis (MS) and may also be a driver of disease activity. Although it is not clear whether ongoing viral replication is the driver for MS pathology, MS researchers have considered the prospect of using drugs with potential efficacy against EBV in the treatment of MS. We have undertaken scientific and lived experience expert panel reviews to shortlist existing licensed therapies that could be used in later-stage clinical trials in MS.
View Article and Find Full Text PDFAppl Biochem Biotechnol
January 2025
Department of Life Science and Biochemical Engineering, Graduate School, SunMoon University, Asan, 31460, Republic of Korea.
Antarctic organisms are known for producing unique secondary metabolites, and this study specifically focuses on the less-explored metabolites of the moss Warnstorfia fontinaliopsis. To evaluate their potential bioactivity, we extracted secondary metabolites using four different solvents and identified significant lipase inhibitory activity in the methanol extract. Non-targeted metabolomic analysis using liquid chromatography-tandem mass spectrometry (LC-MS/MS) on this extract predicted the presence of 12 compounds, including several not previously reported in mosses.
View Article and Find Full Text PDFEnviron Sci Technol
January 2025
School of Ecology and Environmental Science, Yunnan University, Kunming 650504, China.
Safer chemical alternatives to bisphenol (BP) have been a major pursuit of modern green chemistry and toxicology. Using a chemical similarity-based approach, it is difficult to identify minor structural differences that contribute to the significant changes of toxicity. Here, we used omics and computational toxicology to identify chemical features associated with BP analogue-induced embryonic toxicity, offering valuable insights to inform the design of safer chemical alternatives.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
January 2025
Centre for Human Genetics, Nuffield Department of Medicine, University of Oxford, Oxford OX3 7BN, United Kingdom.
A value is conventionally interpreted either as a) the probability by chance of obtaining more extreme results than those observed or b) a tool for declaring significance at a prespecified level. Both approaches carry difficulties: b) does not allow users to make inferences based on the data in hand, and is not rigorously followed by researchers in practice, while (a) is not meaningful as an error rate. Although values retain an important role, these shortcomings are likely to have contributed significantly to the scientific reproducibility crisis.
View Article and Find Full Text PDFAnal Chem
January 2025
Institute for Advanced Optics, Hunan Institute of Science and Technology, Yueyang, Hunan 414006, China.
Diffraction imaging of cells allows rapid phenotyping by the response of intracellular molecules to coherent illumination. However, its ability to distinguish numerous types of human leukocytes remains to be investigated. Here, we show that accurate classification of three lymphocyte subtypes can be achieved with features extracted from cross-polarized diffraction image (p-DI) pairs.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!