INTRODUCTION On March 28,2025,at 06:20:52 UTC,a shallow,magnitude M_(w)7.7 earthquake struck Myanmar(Burma)with an epicenter near the major city of Mandalay.This event,the strongest seismic activity recorded in Myanma...INTRODUCTION On March 28,2025,at 06:20:52 UTC,a shallow,magnitude M_(w)7.7 earthquake struck Myanmar(Burma)with an epicenter near the major city of Mandalay.This event,the strongest seismic activity recorded in Myanmar since 1950,generated intense shaking across much of the country,extended into regions of Thailand,and was felt in China's Yunnan and Guangxi provinces.展开更多
As a main structure of the limbic system,the hippocampus plays a critical role in pain perception and chronicity.The ventral hippocampal CA1(vCA1)is closely associated with negative emotions such as anxiety,stress,and...As a main structure of the limbic system,the hippocampus plays a critical role in pain perception and chronicity.The ventral hippocampal CA1(vCA1)is closely associated with negative emotions such as anxiety,stress,and fear,yet how vCA1 neurons encode nociceptive information remains unclear.Using in vivo electrophysiological recording,we characterized vCA1 pyramidal neuron subpopulations that exhibited inhibitory or excitatory responses to plantar stimuli and were implicated in encoding stimuli modalities in naïve rats.Functional heterogeneity of the vCA1 pyramidal neurons was further identified in neuropathic pain conditions:the proportion and magnitude of the inhibitory response neurons paralleled mechanical allodynia and contributed to the confounded encoding of innocuous and noxious stimuli,whereas the excitatory response neurons were still instrumental in the discrimination of stimulus properties.Increased theta power and theta-spike coupling in vCA1 correlated with nociceptive behaviors.Optogenetic inhibition of vCA1 pyramidal neurons induced mechanical allodynia in naïve rats,whereas chemogenetic reversal of the overall suppressed vCA1 activity had analgesic effects in rats with neuropathic pain.These results provide direct evidence for the representations of nociceptive information in vCA1.展开更多
The prelimbic cortex(PL)is actively engaged in pain modulation.The infralimbic cortex(IL)has been reported to regulate the PL.However,how this regulation affects pain remains unclear.In the present study,we recorded t...The prelimbic cortex(PL)is actively engaged in pain modulation.The infralimbic cortex(IL)has been reported to regulate the PL.However,how this regulation affects pain remains unclear.In the present study,we recorded temporary hyper-activity of PL pyramidal neurons responding to nociceptive stimuli,but a temporary hypofunction of the IL by in vivo electrophysiological recording in rats with peripheral inflammation.Manipulation of the PL or IL had opposite effects on thermal hyperalgesia.Furthermore,the functional connectivity and chemogenetic regulation between the subregions indicated an inhibitory influence of the IL on the PL.Activation of the pathway from the IL to the PL alleviated thermal hyperalgesia,whereas its inhibition exacerbated chronic pain.Overall,our results suggest a new mechanism underlying the role of the medial prefrontal cortex in chronic pain:hypo-function of the IL leads to hyperactivity of the PL,which regulates thermal hyperalgesia,and thus contributes to the chronicity of pain.展开更多
Hamilton energy,which reflects the energy variation of systems,is one of the crucial instruments used to analyze the characteristics of dynamical systems.Here we propose a method to deduce Hamilton energy based on the...Hamilton energy,which reflects the energy variation of systems,is one of the crucial instruments used to analyze the characteristics of dynamical systems.Here we propose a method to deduce Hamilton energy based on the existing systems.This derivation process consists of three steps:step 1,decomposing the vector field;step 2,solving the Hamilton energy function;and step 3,verifying uniqueness.In order to easily choose an appropriate decomposition method,we propose a classification criterion based on the form of system state variables,i.e.,type-I vector fields that can be directly decomposed and type-II vector fields decomposed via exterior differentiation.Moreover,exterior differentiation is used to represent the curl of low-high dimension vector fields in the process of decomposition.Finally,we exemplify the Hamilton energy function of six classical systems and analyze the relationship between Hamilton energy and dynamic behavior.This solution provides a new approach for deducing the Hamilton energy function,especially in high-dimensional systems.展开更多
Neurosteroids are synthesized in the nervous system from cholesterol or steroidal precursors imported from peripheral sources. These compounds are important allosteric modulators of γ-aminobutyric acid A receptors （...Neurosteroids are synthesized in the nervous system from cholesterol or steroidal precursors imported from peripheral sources. These compounds are important allosteric modulators of γ-aminobutyric acid A receptors （GABAARs）, which play a vital role in pain modulation in the lateral thalamus, a main gate where somatosensory information enters the cerebral cortex. Using high-perfor mance liquid chromatography/tandem mass spectrometry, we found increased levels of neurosteroids （pregnenolone, progesterone, deoxycorticosterone, allopregnanolone, and tetrahydrodeoxycorticosterone） in the chronic stage of neuropathic pain （28 days after spared nerve injury） in rats.The expression of the translocator protein TSPO, the upstream steroidogenesis rate-limiting enzyme, increased at the same time. In vivo stereotaxic microinjection of neurosteroids or the TSPO activator AC-5216 into the lateral thalamus （AP -3.0 mm, ML 4-3.0 mm, DV 6.0 mm） alleviated the mechanical allodynia in neuropathic pain, while the TSPO inhibitor PK 11195 exacerbated it. The analgesic effects of AC-5216 and neurosteroids were sig- nificantly attenuated by the GABAAR antagonist bicuculline. These results suggested that elevated neurosteroids in the lateral thalamus play a protective role in the chronic stage of neuropathic pain.展开更多
Tegillarca granosa(T.granosa)is susceptible to heavy metals,which may pose a threat to consumer health.Thus,healthy and polluted T.granosa should be distinguished quickly.This study aimed to rapidly identify heavy met...Tegillarca granosa(T.granosa)is susceptible to heavy metals,which may pose a threat to consumer health.Thus,healthy and polluted T.granosa should be distinguished quickly.This study aimed to rapidly identify heavy metal pollution by using laser-induced breakdown spectroscopy(LIBS)coupled with linear regression classification(LRC).Five types of T.granosa were studied,namely,Cd-,Zn-,Pb-contaminated,mixed contaminated,and control samples.Threshold method was applied to extract the significant variables from LIBS spectra.Then,LRC was used to classify the different types of T.granosa.Other classification models and feature selection methods were used for comparison.LRC was the best model,achieving an accuracy of 90.67%.Results indicated that LIBS combined with LRC is effective and feasible for T.granosa heavy metal detection.展开更多
Cognition and pain share common neural substrates and interact reciprocally: chronic pain compromises cognitive performance, whereas cognitive processes modulate pain perception. In the present study, we established a...Cognition and pain share common neural substrates and interact reciprocally: chronic pain compromises cognitive performance, whereas cognitive processes modulate pain perception. In the present study, we established a non-drug-dependent rat model of context-based analgesia,where two different contexts(dark and bright) were matched with a high(52°C) or low(48°C) temperature in the hot-plate test during training. Before and after training,we set the temperature to the high level in both contexts.Rats showed longer paw licking latencies in trials with the context originally matched to a low temperature than those to a high temperature, indicating successful establishment of a context-based analgesic effect in rats. This effect was blocked by intraperitoneal injection of naloxone(an opioid receptor antagonist) before the probe. The context-based analgesic effect also disappeared after optogenetic activation or inhibition of the bilateral infralimbic or prelimbic sub-region of the prefrontal cortex. In brief, we established a context-based, non-drug dependent, placebo-like analgesia model in the rat. This model provides a new and useful tool for investigating the cognitive modulation of pain.展开更多
Neuronal ensembles with distinct morphological,biochemical,and functional identities are organized into complex circuits in the mammalian brain,and malfunction of specific neuronal types in different networks contribu...Neuronal ensembles with distinct morphological,biochemical,and functional identities are organized into complex circuits in the mammalian brain,and malfunction of specific neuronal types in different networks contributes to diverse pathological symptoms.Taking memory as an example,specific memories are held in a subset of neurons,referred to as engram cells.展开更多
基金supported by the National Key R&D Program of the Republic of China(Nos.2023YFC3007303,2017YFB0504104)the Science and Technology Projects of Gansu Provincial(No.24JRRA1188)。
文摘INTRODUCTION On March 28,2025,at 06:20:52 UTC,a shallow,magnitude M_(w)7.7 earthquake struck Myanmar(Burma)with an epicenter near the major city of Mandalay.This event,the strongest seismic activity recorded in Myanmar since 1950,generated intense shaking across much of the country,extended into regions of Thailand,and was felt in China's Yunnan and Guangxi provinces.
基金supported by the National Natural Science Foundation of China(81974166,32271053,and 31872774).
文摘As a main structure of the limbic system,the hippocampus plays a critical role in pain perception and chronicity.The ventral hippocampal CA1(vCA1)is closely associated with negative emotions such as anxiety,stress,and fear,yet how vCA1 neurons encode nociceptive information remains unclear.Using in vivo electrophysiological recording,we characterized vCA1 pyramidal neuron subpopulations that exhibited inhibitory or excitatory responses to plantar stimuli and were implicated in encoding stimuli modalities in naïve rats.Functional heterogeneity of the vCA1 pyramidal neurons was further identified in neuropathic pain conditions:the proportion and magnitude of the inhibitory response neurons paralleled mechanical allodynia and contributed to the confounded encoding of innocuous and noxious stimuli,whereas the excitatory response neurons were still instrumental in the discrimination of stimulus properties.Increased theta power and theta-spike coupling in vCA1 correlated with nociceptive behaviors.Optogenetic inhibition of vCA1 pyramidal neurons induced mechanical allodynia in naïve rats,whereas chemogenetic reversal of the overall suppressed vCA1 activity had analgesic effects in rats with neuropathic pain.These results provide direct evidence for the representations of nociceptive information in vCA1.
基金supported by the National Natural Foundation of China(32371049,32271053,31872774,81974166,81821092,82101303,32271053,and 32000749)the Beijing Natural Science Foundation(L222016)+1 种基金the China Postdoctoral Science Foundation(2020M670061)the Tianjin Key Laboratory of Brain Science and Neuroengineering.
文摘The prelimbic cortex(PL)is actively engaged in pain modulation.The infralimbic cortex(IL)has been reported to regulate the PL.However,how this regulation affects pain remains unclear.In the present study,we recorded temporary hyper-activity of PL pyramidal neurons responding to nociceptive stimuli,but a temporary hypofunction of the IL by in vivo electrophysiological recording in rats with peripheral inflammation.Manipulation of the PL or IL had opposite effects on thermal hyperalgesia.Furthermore,the functional connectivity and chemogenetic regulation between the subregions indicated an inhibitory influence of the IL on the PL.Activation of the pathway from the IL to the PL alleviated thermal hyperalgesia,whereas its inhibition exacerbated chronic pain.Overall,our results suggest a new mechanism underlying the role of the medial prefrontal cortex in chronic pain:hypo-function of the IL leads to hyperactivity of the PL,which regulates thermal hyperalgesia,and thus contributes to the chronicity of pain.
基金the National Natural Science Foundation of China(Grant Nos.12305054,12172340,and 12371506)。
文摘Hamilton energy,which reflects the energy variation of systems,is one of the crucial instruments used to analyze the characteristics of dynamical systems.Here we propose a method to deduce Hamilton energy based on the existing systems.This derivation process consists of three steps:step 1,decomposing the vector field;step 2,solving the Hamilton energy function;and step 3,verifying uniqueness.In order to easily choose an appropriate decomposition method,we propose a classification criterion based on the form of system state variables,i.e.,type-I vector fields that can be directly decomposed and type-II vector fields decomposed via exterior differentiation.Moreover,exterior differentiation is used to represent the curl of low-high dimension vector fields in the process of decomposition.Finally,we exemplify the Hamilton energy function of six classical systems and analyze the relationship between Hamilton energy and dynamic behavior.This solution provides a new approach for deducing the Hamilton energy function,especially in high-dimensional systems.
基金supported by grants from the National Basic Research Development Program of China(2013CB531905,2014CB548200,and 2015CB554503)the National Natural Science Foundation of China(81230023,81221002,31200835,81571067,and 21305005)+1 种基金a Key Project of the Ministry of Education of China(109003)the ‘‘111’’ Project of the Ministry of Education of China(B07001)
文摘Neurosteroids are synthesized in the nervous system from cholesterol or steroidal precursors imported from peripheral sources. These compounds are important allosteric modulators of γ-aminobutyric acid A receptors （GABAARs）, which play a vital role in pain modulation in the lateral thalamus, a main gate where somatosensory information enters the cerebral cortex. Using high-perfor mance liquid chromatography/tandem mass spectrometry, we found increased levels of neurosteroids （pregnenolone, progesterone, deoxycorticosterone, allopregnanolone, and tetrahydrodeoxycorticosterone） in the chronic stage of neuropathic pain （28 days after spared nerve injury） in rats.The expression of the translocator protein TSPO, the upstream steroidogenesis rate-limiting enzyme, increased at the same time. In vivo stereotaxic microinjection of neurosteroids or the TSPO activator AC-5216 into the lateral thalamus （AP -3.0 mm, ML 4-3.0 mm, DV 6.0 mm） alleviated the mechanical allodynia in neuropathic pain, while the TSPO inhibitor PK 11195 exacerbated it. The analgesic effects of AC-5216 and neurosteroids were sig- nificantly attenuated by the GABAAR antagonist bicuculline. These results suggested that elevated neurosteroids in the lateral thalamus play a protective role in the chronic stage of neuropathic pain.
基金This research was funded by National Natural Science Foundation of China(Nos.31571920,61671378)。
文摘Tegillarca granosa(T.granosa)is susceptible to heavy metals,which may pose a threat to consumer health.Thus,healthy and polluted T.granosa should be distinguished quickly.This study aimed to rapidly identify heavy metal pollution by using laser-induced breakdown spectroscopy(LIBS)coupled with linear regression classification(LRC).Five types of T.granosa were studied,namely,Cd-,Zn-,Pb-contaminated,mixed contaminated,and control samples.Threshold method was applied to extract the significant variables from LIBS spectra.Then,LRC was used to classify the different types of T.granosa.Other classification models and feature selection methods were used for comparison.LRC was the best model,achieving an accuracy of 90.67%.Results indicated that LIBS combined with LRC is effective and feasible for T.granosa heavy metal detection.
基金supported by grants from the National Natural Science Foundation of China (91732107, 31200835, 81571067, and 81521063)the National Basic Research Development Program (973 Program) of China (2014CB548200 and 2015CB554503)
文摘Cognition and pain share common neural substrates and interact reciprocally: chronic pain compromises cognitive performance, whereas cognitive processes modulate pain perception. In the present study, we established a non-drug-dependent rat model of context-based analgesia,where two different contexts(dark and bright) were matched with a high(52°C) or low(48°C) temperature in the hot-plate test during training. Before and after training,we set the temperature to the high level in both contexts.Rats showed longer paw licking latencies in trials with the context originally matched to a low temperature than those to a high temperature, indicating successful establishment of a context-based analgesic effect in rats. This effect was blocked by intraperitoneal injection of naloxone(an opioid receptor antagonist) before the probe. The context-based analgesic effect also disappeared after optogenetic activation or inhibition of the bilateral infralimbic or prelimbic sub-region of the prefrontal cortex. In brief, we established a context-based, non-drug dependent, placebo-like analgesia model in the rat. This model provides a new and useful tool for investigating the cognitive modulation of pain.
基金supported by grants from the National Natural Science Foundation of China(81974166,31872774,31371119,91732107,and 81821092)Beijing Natural Science Foundation(7202083,5182013)+1 种基金the National Basic Research(973)Program of the Ministry of Science and Technology of China(2014CB548200 and 2015CB554503)the Interdisciplinary Medicine Seed Fund of Peking University(BMU2018MX011)。
文摘Neuronal ensembles with distinct morphological,biochemical,and functional identities are organized into complex circuits in the mammalian brain,and malfunction of specific neuronal types in different networks contributes to diverse pathological symptoms.Taking memory as an example,specific memories are held in a subset of neurons,referred to as engram cells.
