Diagnosing and classifying central nervous system tumors such as gliomas or glioblastomas pose a significant challenge due to their aggressive and infiltrative nature. However, recent advancements in metabolomics and magnetic resonance spectroscopy (MRS) offer promising avenues for differentiating tumor grades both in vivo and ex vivo. This study aimed to explore tissue-based metabolic signatures to classify/distinguish between low- and high-grade gliomas.
View Article and Find Full Text PDFAm J Physiol Gastrointest Liver Physiol
December 2024
Gastric peristalsis is governed by electrical "slow waves" generally assumed to travel from proximal to distal stomach (antegrade propagation) in symmetric rings. Although alternative slow-wave patterns have been correlated with gastric disorders, their mechanisms and how they alter contractions remain understudied. Optical electromechanical mapping, a developing field in cardiac electrophysiology, images electrical and mechanical physiology simultaneously.
View Article and Find Full Text PDFRhythmic electrical events, termed slow waves, govern the timing and amplitude of phasic contractions of the gastric musculature. Extracellular multielectrode measurement of gastric slow waves can be a biomarker for phenotypes of motility dysfunction. However, a gastric slow-wave conduction pathway for the rat, a common animal model, is unestablished.
View Article and Find Full Text PDFAm J Physiol Gastrointest Liver Physiol
June 2024
The motility of the gastrointestinal tract is coordinated in part by rhythmic slow waves, and disrupted slow-wave patterns are linked to functional motility disorders. At present, there are no treatment strategies that primarily target slow-wave activity. This study assessed the use of pacing to suppress glucagon-induced slow-wave dysrhythmias in the small intestine.
View Article and Find Full Text PDFThe uterus exhibits intermittent electrophysiological activity in vivo. Although most active during labor, the non-pregnant uterus can exhibit activity of comparable magnitude to the early stages of labor. In this study, two types of flexible electrodes were utilized to measure the electrical activity of uterine smooth muscle in vivo in anesthetized, non-pregnant rats.
View Article and Find Full Text PDFBackground: The National Cancer Institute issued a Request for Information (RFI; NOT-CA-23-007) in October 2022, soliciting input on using and reusing metabolomics data. This RFI aimed to gather input on best practices for metabolomics data storage, management, and use/reuse.
Aim Of Review: The nuclear magnetic resonance (NMR) Interest Group within the Metabolomics Association of North America (MANA) prepared a set of recommendations regarding the deposition, archiving, use, and reuse of NMR-based and, to a lesser extent, mass spectrometry (MS)-based metabolomics datasets.
Pacing has been proposed as a therapy to restore function in motility disorders associated with electrical dysrhythmias. The spatial response of bioelectrical activity in the small intestine to pacing is poorly understood due to a lack of high-resolution investigations. This study systematically varied pacing parameters to determine the optimal settings for the spatial entrainment of slow wave activity in the jejunum.
View Article and Find Full Text PDFThermochromism, the change in color of a material with temperature, is the fundamental basis of optical thermometry. A longstanding challenge in realizing sensitive optical thermometers for widespread use is identifying materials with pronounced thermometric optical performance in the visible range. Herein, it is demonstrated that single crystals of indium selenium iodide (InSeI), a 1D van der Waals (vdW) solid consisting of weakly bound helical chains, exhibit considerable visible range thermochromism.
View Article and Find Full Text PDFSwallowing is a primary and complex behaviour that transports food and drink from the oral cavity, through the pharynx and oesophagus, into the stomach at an appropriate rate and speed. To understand this sophisticated behaviour, a tremendous amount of research has been carried out by utilising the in vivo approach, which is often challenging to perform, poses a risk to the subjects if interventions are undertaken and are seldom able to control for confounding factors. In contrast, in silico (computational) and in vitro (instrumental) methods offer an alternate insight into the process of the human swallowing system.
View Article and Find Full Text PDFSoft gastric simulators are biomimetic modules that can reproduce the antral contraction waves (ACWs). Along with providing information concerning stomach contents, stomach simulators enable experts to evaluate the digestion process of foods and drugs. Traditionally, open-loop control approaches were implemented on stomach simulators to produce ACWs.
View Article and Find Full Text PDFNeural regulation of gastric motility occurs partly through the regulation of gastric bioelectrical slow waves (SWs) and phasic contractions. The interaction of the tissues and organs involved in this regulatory process is complex. We sought to infer the relative importance of cellular mechanisms in inhibitory neural regulation of the stomach by enteric neurons and the interaction of inhibitory and excitatory electrical field stimulation.
View Article and Find Full Text PDFAnnu Int Conf IEEE Eng Med Biol Soc
July 2023
Gastrointestinal (GI) sphincters provide critical roles in regulating the transport of contents along the GI tract. Dysfunctions of GI sphincters are associated with a range of major digestive disorders. Despite their importance, the microstructures of GI sphincters are not well investigated.
View Article and Find Full Text PDFThe primary function of the duodenum is to undertake chemical digestion by ensuring that the partially digested food received from the stomach is well-mixed with the enzymes and chemicals secreted into it. However, little is known about the anatomical variations in the shape of the duodenum within humans, and thus the effect of duodenum shape on the flow and mixing occurring within the lumen has not been studied. In this work, a methodology for analyzing shape variations in the normal duodenal anatomy has been developed and applied to a publicly available dataset of abdominal CT images.
View Article and Find Full Text PDFAnnu Int Conf IEEE Eng Med Biol Soc
July 2023
Postoperative ileus and chronic intestinal pseudo-obstruction are intestinal motility disorders that can compromise bowel function resulting in a significant reduction in quality of life and prolonged hospital stays. While medication and nutritional support provides relief for some patients, a significant patient population remains untreated. Therefore, alternative treatment options are required.
View Article and Find Full Text PDFAnnu Int Conf IEEE Eng Med Biol Soc
July 2023
A framework to simulate the flow in the stomach using subject-specific motility patterns and geometries was developed. Dynamic 2D magnetic resonance images (MRIs) were obtained. Motility parameters such as contraction speed and occlusion were quantified, and 3D stomach geometries were reconstructed using a semi-automated approach.
View Article and Find Full Text PDFAnnu Int Conf IEEE Eng Med Biol Soc
July 2023
Swallowing involves the precise coordination of a large number of muscles. This coordination can be quantified non-invasively by electromyographic (EMG) time-series analysis of swallowing events. The temporal alignment of swallow events is critical for defining coordination patterns.
View Article and Find Full Text PDFAnnu Int Conf IEEE Eng Med Biol Soc
July 2023
Cervical vagus nerve stimulation (cVNS) is a promising neuromodulation therapy for treating symptoms of disease in peripheral organs. The rat is a common animal model for studying and trialing new applications of cVNS therapy, but the stomach and its activity in rats is less well characterized than other animals, such as pigs. We sought to investigate the effects of acute, in vivo cVNS on gastric bioelectrical activity as an intermediate step to computational modeling of the effects of cVNS on gastric smooth muscle electromechanical coupling.
View Article and Find Full Text PDFObjective: Bioelectrical 'slow waves' regulate gastrointestinal contractions. We aimed to confirm whether the pyloric sphincter demarcates slow waves in the intact stomach and duodenum.
Methods: We developed and validated novel anatomically-specific electrode cradles and analysis techniques which enable high-resolution slow wave mapping across the in vivo gastroduodenal junction.
Intestinal motility is governed in part by bioelectrical slow-waves and spike-bursts. Mesenteric ischemia is a substantial clinical challenge, but its electrophysiological and contractile mechanisms are not well understood. Simultaneous high-resolution bioelectrical and video mapping techniques were used to capture the changes in slow-waves, spike-bursts, and contractile activity during baseline, ischemia, and reperfusion periods.
View Article and Find Full Text PDFBackground: Renal cell carcinoma (RCC) is a metabolic disease, with subtypes exhibiting aberrations in different metabolic pathways. Metabolomics may offer greater sensitivity for revealing disease biology. We investigated the metabolomic profile of RCC using high-resolution magic angle spinning (HRMAS) proton magnetic resonance spectroscopy (HMRS).
View Article and Find Full Text PDFStickland-fermenting preferentially ferment amino acids to generate energy and anabolic substrates for growth. In gut ecosystems, these species prefer dual redox substrates, particularly mucin-abundant leucine. Here, we establish how theronine, a more prevalent, mucinabundant substrate, supports dual redox metabolism in the pathogen .
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