Publications by authors named "Wen-Chang Li"

Forkhead box D1 (FOXD1) serves a critical role in colorectal cancer (CRC). FOXD1 expression is an independent prognostic factor in patients with CRC; however, the molecular mechanism and signaling pathway of FOXD1 that regulates cell stemness and chemoresistance has not been fully characterized. The aim of the present study was to further validate the effect of FOXD1 on the proliferation and migration of CRC cells, and to delve into the possible potential of FOXD1 in the clinical treatment of CRC.

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  • Developing spinal circuits in hatchling frog tadpoles create swimming movements even as some neurons are still maturing.
  • Research found that the reliability of inhibitory interneurons in swimming is inversely related to their membrane resistance, affecting their firing properties.
  • Incorporating the electrical and synaptic characteristics of these neurons into a computer model demonstrated that their recruitment during swimming differs from traditional recruitment models, highlighting the role of membrane resistance in neural development.
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  • * Researchers identified 7762 genes with altered expression in zebrafish spinal cords, focusing on those related to axon regeneration and metabolic pathways during recovery.
  • * The study highlights two key genes, clasp2 and h1m, with potential as therapeutic targets for spinal cord injury repair, emphasizing their roles in axon extension and stem cell differentiation.
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has a lateral line mechanosensory system throughout its full life cycle, and a previous study on prefeeding stage tadpoles revealed that it may play a role in motor responses to both water suction and water jets. Here, we investigated the physiology of the anterior lateral line system in newly hatched tadpoles and the motor outputs induced by its activation in response to brief suction stimuli. High-speed videoing showed tadpoles tended to turn and swim away when strong suction was applied close to the head.

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Background: Neoadjuvant therapy (NAT) is becoming increasingly important in locally advanced rectal cancer. Hence, such research has become a problem.

Aim: To evaluate the downstaging effect of NAT, its impact on postoperative complications and its prognosis with different medical regimens.

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tadpoles have been an excellent, simple vertebrate model for studying the basic organization and physiology of the spinal cord and motor centers in the brainstem. In the past, intracellular recordings from the spinal and brainstem neurons were primarily made using sharp electrodes, although whole-cell patch-clamp technology has been around since the early 1980s. In this protocol, I describe the dissections and procedures needed for in situ whole-cell patch-clamp recording, which has become routine in tadpole neurophysiology since the early 2000s.

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All animals use sensory systems to monitor external events and have to decide whether to move. Response times are long and variable compared to reflexes, and fast escape movements. The complexity of adult vertebrate brains makes it difficult to trace the neuronal circuits underlying basic decisions to move.

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Vertebrate central pattern generators (CPGs) controlling locomotion contain neurons which provide the excitation that drives and maintains network rhythms. In a simple vertebrate, the developing tadpole, we study the role of excitatory descending neurons with ipsilateral projecting axons (descending interneurons, dINs) in the control of swimming rhythms. In tadpoles with both intact central nervous system (CNS) and transections in the hindbrain, exciting some individual dINs in the caudal hindbrain region could start swimming repeatedly.

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Key Points: Short-term working memory and decision-making are usually studied in the cerebral cortex; in many models of simple decision making, sensory signals build slowly and noisily to threshold to initiate a motor response after long, variable delays. When touched, hatchling frog tadpoles decide whether to swim; we define the long and variable delays to swimming and use whole-cell recordings to uncover the neurons and processes responsible. Firing in sensory and sensory pathway neurons is short latency, and too brief and invariant to explain these delays, while recordings from hindbrain reticulospinal neurons controlling swimming reveal a prolonged and variable build-up of synaptic excitation which can reach firing threshold and initiate swimming.

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We present the study of a minimal microcircuit controlling locomotion in two-day-old Xenopus tadpoles. During swimming, neurons in the spinal central pattern generator (CPG) generate anti-phase oscillations between left and right half-centres. Experimental recordings show that the same CPG neurons can also generate transient bouts of long-lasting in-phase oscillations between left-right centres.

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Muscarinic acetylcholine receptors (mAChRs) mediate effects of acetylcholine (ACh) in many systems, including those involved in spinal functions like locomotion. In Xenopus laevis tadpoles at two days old, a model vertebrate for motor control research, we investigated the role of mAChRs in the skin mechanosensory pathway. We found that mAChR activation by carbachol did not affect the sensory Rohon-Beard neuron properties.

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We present a detailed computational model of interacting neuronal populations that mimic the hatchling Xenopus tadpole nervous system. The model includes four sensory pathways, integrators of sensory information, and a central pattern generator (CPG) network. Sensory pathways of different modalities receive inputs from an "environment"; these inputs are then processed and integrated to select the most appropriate locomotor action.

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Most vertebrates show concussion responses when their heads are hit suddenly by heavy objects. Previous studies have focused on the direct physical injuries to the neural tissue caused by the concussive blow. We study a similar behavior in a simple vertebrate, the tadpole.

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Persistent sodium currents () are common in neuronal circuitries and have been implicated in several diseases, such as amyotrophic lateral sclerosis (ALS) and epilepsy. However, the role of in the regulation of specific behaviors is still poorly understood. In this study we have characterized and investigated its role in the swimming and struggling behavior of tadpoles.

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Activity-dependent modification of neural network output usually results from changes in neurotransmitter release and/or membrane conductance. In Xenopus frog tadpoles, spinal locomotor network output is adapted by an ultraslow afterhyperpolarization (usAHP) mediated by an increase in Na(+) pump current. Here we systematically explore how the interval between two swimming episodes affects the second episode, which is shorter and slower than the first episode.

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Many neural circuits show fast reconfiguration following altered sensory or modulatory inputs to generate stereotyped outputs. In the motor circuit of Xenopus tadpoles, I study how certain voltage-dependent ionic currents affect firing thresholds and contribute to circuit reconfiguration to generate two distinct motor patterns, swimming and struggling. Firing thresholds of excitatory interneurons [i.

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Many neural circuits are capable of generating multiple stereotyped outputs after different sensory inputs or neuromodulation. We have previously identified the central pattern generator (CPG) for Xenopus tadpole swimming that involves antiphase oscillations of activity between the left and right sides. Here we analyze the cellular basis for spontaneous left-right motor synchrony characterized by simultaneous bursting on both sides at twice the swimming frequency.

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Neuroscience labs benefit from reliable, easily-monitored neural responses mediated by well-studied neural pathways. Xenopus laevis tadpoles have been used as a simple vertebrate model preparation in motor control studies. Most of the neuronal pathways underlying different aspects of tadpole swimming behavior have been revealed.

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Alternating contractions of antagonistic muscle groups during locomotion are generated by spinal "half-center" networks coupled in antiphase by reciprocal inhibition. It is widely thought that reciprocal inhibition only coordinates the activity of these muscles. We have devised two methods to rapidly and selectively silence neurons on just one side of Xenopus tadpole spinal cord and hindbrain, which generate swimming rhythms.

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Every type of neural rhythm has its own operational range of frequency. Neuronal mechanisms underlying rhythms at different frequencies, however, are poorly understood. We use a simple aquatic vertebrate, the two-day-old Xenopus tadpole, to investigate how the brainstem and spinal circuits generate swimming rhythms of different speeds.

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Objective: To study the lipids level in Kazakan individuals over 30-year-old in Fukang area of Xinjiang.

Methods: Random cluster multistage sampling method were performed to select the subjects, and 991 individuals aged older than 30 from Fukang of Xinjiang were included. The plasma total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), plasma glucose and insulin were measured.

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Locomotion rhythms are thought to be generated by neurons in the central-pattern-generator (CPG) circuit in the spinal cord. Synaptic connections in the CPG and pacemaker properties in certain CPG neurons, both may contribute to generation of the rhythms. In the half-center model proposed by Graham Brown a century ago, reciprocal inhibition plays a critical role.

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In young and developing amphibians and fish the spinal cord is functional but remarkably simple compared with the adult. Is the pattern of neurons and their connections common across at least these lower vertebrates? Does this basic pattern extend into the brainstem? Could the development of simple functioning neuronal networks depend on very basic rules of connectivity and act as pioneer networks providing a substrate for the development of more complex and subtle networks. In this review of the functional neuron classes in the Xenopus laevis tadpole spinal cord up to hatching, we will consider progress and difficulties in using anatomy, transcription factor expression, physiology, and activity to define spinal neuron types.

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Rhythmic activity is central to brain function. In the vertebrate CNS, the neuronal circuits for breathing and locomotion involve inhibition and also neurons acting as pacemakers, but identifying the neurons responsible has proven difficult. By studying simple hatchling Xenopus laevis tadpoles, we have already identified a population of electrically coupled hindbrain neurons (dINs) that drive swimming.

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