Clinical efficacy of Baijin pills in the treatment of generalized tonicclonic seizure epilepsy with cognitive impairment

BACKGROUND The generalized tonic-clonic seizure(GTCS)is the most usual variety of epileptic seizure.It is mainly characterized by strong body muscle rigidity,loss of consciousness,a disorder of plant neurofunction,and significant damage to cognitive function.The effect of antiepileptic drugs on cognition should also be considered.At present,there is no effective treatment for patients with epilepsy,but traditional Chinese medicine has shown a significant effect on chronic disease with fewer harmful side effects and should,therefore,be considered for the therapy means of epilepsy with cognitive dysfunction.AIM To investigate the clinical efficacy of Baijin pills for treating GTCS patients with cognitive impairment.METHODS This prospective study enrolled patients diagnosed with GTCS between January 2020 and December 2023 and separate them into two groups(experimental and control)using random number table method.The control group was treated with sodium valproate,and the experimental group was Baijin pills and sodium valproate for three months.The frequency and duration of each seizure,the Montreal Cognitive Assessment Scale(MoCA),and the Quality of Life Rating Scale(QOLIE-31)were recorded before and after treatment.RESULTS There were 85 patients included(42 in the control group and 43 in the experimental group).After treatment,the seizure frequency in the experimental group was significantly reduced(P<0.05),and seizure duration was shortened(P<0.01).The total MoCA score in the experimental group significantly increased compared to before treatment(P<0.01),and the sub-item scores,except naming and abstract generalization ability,significantly increased(P<0.05),whereas the total MoCA score in the control group significantly decreased after treatment(P<0.05).The QOLIE-31 score of the experimental group increased significantly after treatment compared to before treatment(P<0.01).CONCLUSION Baijin pills have a good clinical effect on epilepsy with cognitive dysfunction.

Abnormal Basal Ganglia Functional Connectivity in Idiopathic Generalized Epilepsy

The basal ganglia have been implicated in a modulation role in idiopathic generalized epilepsy （IGE） by an invasive electrophysioigic means. This paper investigates the basal ganglia functional connectivity by using the region-wise functional connection analysis in resting-state functional magnetic resonance imaging （fMRI） in IGE. The increased functional connectivity within basal ganglia, and between the basal ganglia and the thalamus, and decreased functional connectivity between basal ganglia and motor cortex are found in IGE compared with the controls. These findings not only implicate dysfunctional integration in the motor loop in IGE and the enhanced interaction in the modulated loop, but also suggest that the basal ganglia modulate the generalized epileptic discharges with the influence over thalamus in the corticothalamus network.

Correlation between human seizure-related gene 6 variants and idiopathic generalized epilepsy in a Southern Chinese Han population

This study sought to analyze the genotype and gene mutations of human seizure-related gene 6 in 98 patients with idiopathic generalized epilepsy （non-febrile seizures）, who were selected from three generations of the Chinese Han population living in Shanghai, Zhejiang Province, Wuxi of Jiangsu Province, and Jiangxi Province of Southern China. Twenty-six patients＇ parents were available as a first-degree relatives group and 100 biologically unrelated healthy controls were collected as the control group. Based on the age of onset and seizure type, the patients were divided into six subgroups. Polymerase chain reaction and DNA direct sequencing analysis showed that the most frequent mutations c. 1249dupC （p.Gly418Argfx31 ） and c.1636A 〉 G （p.Thr546Ala） were detected in some idiopathic generalized epilepsy patients and tl^eir asymptomatic first-degree relatives （30.6% vs. 19.2% and 11.2% vs. 26.9%）. A novel mutation c.1807G 〉A （p.Val603Met） was found in a patient with late-onset idiopathic generalized epilepsy. There was no significant difference in the incidence of these three mutations among the different subgroups of idiopathic generalized epilepsy and controls. Thus, further analysis of a larger population is needed to confirm the assumption that human seizure-related gene 6 is a susceptibility gene for idiopathic generalized epilepsy with various sub-syndromes.

Pathogenesis, diagnosis, and treatment of epilepsy: electromagnetic stimulation-mediated neuromodulation therapy and new technologies

Epilepsy is a severe,relapsing,and multifactorial neurological disorder.Studies regarding the accurate diagnosis,prognosis,and in-depth pathogenesis are crucial for the precise and effective treatment of epilepsy.The pathogenesis of epilepsy is complex and involves alterations in variables such as gene expression,protein expression,ion channel activity,energy metabolites,and gut microbiota composition.Satisfactory results are lacking for conventional treatments for epilepsy.Surgical resection of lesions,drug therapy,and non-drug interventions are mainly used in clinical practice to treat pain associated with epilepsy.Non-pharmacological treatments,such as a ketogenic diet,gene therapy for nerve regeneration,and neural regulation,are currently areas of research focus.This review provides a comprehensive overview of the pathogenesis,diagnostic methods,and treatments of epilepsy.It also elaborates on the theoretical basis,treatment modes,and effects of invasive nerve stimulation in neurotherapy,including percutaneous vagus nerve stimulation,deep brain electrical stimulation,repetitive nerve electrical stimulation,in addition to non-invasive transcranial magnetic stimulation and transcranial direct current stimulation.Numerous studies have shown that electromagnetic stimulation-mediated neuromodulation therapy can markedly improve neurological function and reduce the frequency of epileptic seizures.Additionally,many new technologies for the diagnosis and treatment of epilepsy are being explored.However,current research is mainly focused on analyzing patients’clinical manifestations and exploring relevant diagnostic and treatment methods to study the pathogenesis at a molecular level,which has led to a lack of consensus regarding the mechanisms related to the disease.

The role of axon guidance molecules in the pathogenesis of epilepsy

Current treatments for epilepsy can only manage the symptoms of the condition but cannot alter the initial onset or halt the progression of the disease. Consequently, it is crucial to identify drugs that can target novel cellular and molecular mechanisms and mechanisms of action. Increasing evidence suggests that axon guidance molecules play a role in the structural and functional modifications of neural networks and that the dysregulation of these molecules is associated with epilepsy susceptibility. In this review, we discuss the essential role of axon guidance molecules in neuronal activity in patients with epilepsy as well as the impact of these molecules on synaptic plasticity and brain tissue remodeling. Furthermore, we examine the relationship between axon guidance molecules and neuroinflammation, as well as the structural changes in specific brain regions that contribute to the development of epilepsy. Ample evidence indicates that axon guidance molecules, including semaphorins and ephrins, play a fundamental role in guiding axon growth and the establishment of synaptic connections. Deviations in their expression or function can disrupt neuronal connections, ultimately leading to epileptic seizures. The remodeling of neural networks is a significant characteristic of epilepsy, with axon guidance molecules playing a role in the dynamic reorganization of neural circuits. This, in turn, affects synapse formation and elimination. Dysregulation of these molecules can upset the delicate balance between excitation and inhibition within a neural network, thereby increasing the risk of overexcitation and the development of epilepsy. Inflammatory signals can regulate the expression and function of axon guidance molecules, thus influencing axonal growth, axon orientation, and synaptic plasticity. The dysregulation of neuroinflammation can intensify neuronal dysfunction and contribute to the occurrence of epilepsy. This review delves into the mechanisms associated with the pathogenicity of axon guidance molecules in epilepsy, offering a valuable reference for the exploration of therapeutic targets and presenting a fresh perspective on treatment strategies for this condition.

Treadmill exercise improves hippocampal neural plasticity and relieves cognitive deficits in a mouse model of epilepsy

Epilepsy frequently leads to cognitive dysfunction and approaches to treatment remain limited.Although regular exercise effectively improves learning and memory functions across multiple neurological diseases,its application in patients with epilepsy remains controversial.Here,we adopted a 14-day treadmill-exercise paradigm in a pilocarpine injection-induced mouse model of epilepsy.Cognitive assays confirmed the improvement of object and spatial memory after endurance training,and electrophysiological studies revealed the maintenance of hippocampal plasticity as a result of physical exercise.Investigations of the mechanisms underlying this effect revealed that exercise protected parvalbumin interneurons,probably via the suppression of neuroinflammation and improved integrity of blood-brain barrier.In summary,this work identified a previously unknown mechanism through which exercise improves cognitive rehabilitation in epilepsy.

Aberrant adult neurogenesis in intractable epilepsy:can GABAergic progenitor transplantation normalize this process?

Temporal lobe epilepsy(TLE) is a common type of focal epilepsy characterized by seizure foci within the temporal lobes.While surgical resection of the foci is an established and effective approach for controlling seizures,both temporal lobes cannot be removed,due to their prominent roles in learning and memory.Additionally,seizures induce changes to the temporal lobes that contribute to hyperexcitability,including mossy fiber sprouting,astrogliosis.

Astrocyte chloride,excitatory-inhibitory balance and epilepsy

Excitation and inhibition are at the core of brain function and malfunction.To sustain the activity of neuronal networks over time and space,glutamatergic excitation is balanced by GABAergic inhibition.The equipoise of excitation and inhibition,known as the excitation/inhibition(E/I)balance,is crucial for proper brain function.The E/I balance is highly dynamic and shifts across different brain states:wakefulness primarily augments excitatory activity,while sleep promotes a decrease in excitation and an increase in inhibition(Bridi et al.,2020).Neuronal activity during various brain states is primarily regulated by neurotransmitters(Schiemann et al.,2015),alongside non-synaptic mechanisms that operate on a slower timescale.The non-synaptic mechanisms are many,with the ionic composition of the extracellular space playing a significant role;altering extracellular ion concentrations affects sleep,arousal,electroencephalogram patterns,and behavioral states(Ding et al.,2016).

Psychiatric comorbidities in epilepsy:population co-occurrence,genetic correlations and causal effects

Background Psychiatric comorbidities are common in patients with epilepsy.Reasons for the co-occurrence of psychiatric conditions and epilepsy remain poorly understood.Aim We aimed to triangulate the relationship between epilepsy and psychiatric conditions to determine the extent and possible origins of these conditions.Methods Using nationwide Swedish health registries,we quantified the lifetime prevalence of psychiatric disorders in patients with epilepsy.We then used summarydata from genome-wide association studies to investigate whether the identified observational associations could be attributed to a shared underlying genetic aetiology using cross-trait linkage disequilibrium score regression.Finally,we assessed the potential bidirectional relationships using two-sample Mendelian randomisation.Results In a cohort of 7628495 individuals,we found that almost half of the 94435 individuals diagnosed with epilepsy were also diagnosed with a psychiatric condition in their lifetime(adjusted lifetime prevalence,44.09%;95%confidence interval(Cl)43.78%to 44.39%).We found evidence for a genetic correlation between epilepsy and some neurodevelopmental and psychiatric conditions.For example,we observed a genetic correlation between epilepsy and attention-deficit/hyperactivity disorder(r,=0.18,95%Cl 0.09 to 0.27,p<0.001)—a correlation that was more pronounced in focal epilepsy(r=0.23,95%CI 0.09 to 0.36,p<0.001).Findings from Mendelian randomisation using common genetic variants did not support bidirectional effects between epilepsy and neurodevelopmental or psychiatric conditions.Conclusions Psychiatric comorbidities are common in patients with epilepsy.Genetic correlations may partially explain some comorbidities;however,there is little evidence of a bidirectional relationship between the genetic liability of epilepsy and psychiatric conditions.These findings highlight the need to understand the role of environmental factors or rare genetic variations in the origins of psychiatric comorbidities in epilepsy.

Nrf2 as a potential target for the treatment of epilepsy

Epilepsy is a prevalent chronic brain disorder that is characterized by a persistent predisposition to recurrently generate epileptic seizures and is often associated with cognitive and psychological consequences.Epilepsy affects approximately 65 million individuals,including both males and females of all ages worldwide,and poses a significant burden on patients,their families,and the health system(Vezzani et al.,2019).

Electroencephalogram findings in 10 patients with post-stroke epilepsy:A retrospective study

BACKGROUND Post-stroke epilepsy is a common and easily overlooked complication of acute cerebrovascular disease.Long-term seizures can seriously affect the prognosis and quality of life of patients.Electroencephalogram(EEG)is the simplest way to diagnose epilepsy,and plays an important role in predicting seizures and guiding medication.AIM To explore the EEG characteristics of patients with post-stroke epilepsy and improve the detection rate of inter-seizure epileptiform discharges.METHODS From January 2017 to June 2020,10 patients with post-stroke epilepsy in our hospital were included.The clinical,imaging,and EEG characteristics were collected.The stroke location,seizure type,and ictal and interictal EEG manifestations of the patients with post-stroke epilepsy were then retrospectively analyzed.RESULTS In all 10 patients,epileptiform waves occurred in the side opposite to the stroke lesion during the interictal stage;these manifested as sharp wave,sharp-wave complex,or spike discharges in the anterior head lead of the side opposite to the lesion.CONCLUSION In EEG,epileptiform waves can occur in the side opposite to the stroke lesion in patients with post-stroke epilepsy.

Cognitive Disorders, Depression and Anxiety in Temporal Lobe Epilepsy: An Overview

Partial epilepsies, originating in a specific brain region, affect about 60% of adults with epilepsy. Temporal lobe epilepsy (TLE) is the most prevalent subtype within this category, often necessitating surgical intervention due to its refractoriness to antiepileptic drugs (AEDs). Hippocampal sclerosis, a common underlying pathology, often exacerbates the severity by introducing cognitive and emotional challenges. This review delves deeper into the cognitive profile of TLE, along with the risk factors for cognitive disorders, depression, and anxiety in this population.

Bibliometric analysis of research in epilepsy and comorbid depression from 2014 to 2023

BACKGROUND Epilepsy and depression have complicated bidirectional relationships.Our study aimed to explore the field of epilepsy comorbid with depression in a bibliometric perspective from 2014-2023.AIM To improve our understanding of epilepsy and depression by evaluating the relationship between epilepsy and depression,bibliometric analyses were performed.METHODS Epilepsy and depression-related publications from the last decade were retrieved from the Web of Science Core Collection.We conducted bibliometric and visual analysis using VOSviewer and CiteSpace,examining authorships,countries,institutions,journals of publication,co-citations of references,connections between keywords,clusters of keywords,and keywords with citation bursts.RESULTS Over the past ten years,we collected 1045 research papers focusing on the field of epilepsy and comorbid depression.Publications on epilepsy and depression have shown a general upward trend over time,though with some fluctuations.The United States,with 287 articles,and the University of Melbourne,contributing 34 articles,were the top countries and institutions,respectively.In addition,in the field of epilepsy and depression,Professor Lee,who has published 30 articles,was the most contributing author.The hot topics pay attention to the quality of life in patients with epilepsy and depression.CONCLUSION We reported that quality of life and stigma in patients with epilepsy comorbid with depression are possible future hot topics and directions in the field of epilepsy and depression research.

Necessary and Sufficient Conditions for Oscillations of the Generalized Liénard Systems

In this paper, we study the second-order nonlinear differential systems of Liénard-type x˙=1a(x)[ h(y)−F(x) ], y˙=−a(x)g(x). Necessary and sufficient conditions to ensure that all nontrivial solutions are oscillatory are established by using a new nonlinear integral inequality. Our results substantially extend and improve previous results known in the literature.

Generalized load graphical forecasting method based on modal decomposition

In a“low-carbon”context,the power load is affected by the coupling of multiple factors,which gradually evolves from the traditional“pure load”to the generalized load with the dual characteristics of“load+power supply.”Traditional time-series forecasting methods are no longer suitable owing to the complexity and uncertainty associated with generalized loads.From the perspective of image processing,this study proposes a graphical short-term prediction method for generalized loads based on modal decomposition.First,the datasets are normalized and feature-filtered by comparing the results of Xtreme gradient boosting,gradient boosted decision tree,and random forest algorithms.Subsequently,the generalized load data are decomposed into three sets of modalities by modal decomposition,and red,green,and blue(RGB)images are generated using them as the pixel values of the R,G,and B channels.The generated images are diversified,and an optimized DenseNet neural network was used for training and prediction.Finally,the base load,wind power,and photovoltaic power generation data are selected,and the characteristic curves of the generalized load scenarios under different permeabilities of wind power and photovoltaic power generation are obtained using the density-based spatial clustering of applications with noise algorithm.Based on the proposed graphical forecasting method,the feasibility of the generalized load graphical forecasting method is verified by comparing it with the traditional time-series forecasting method.

Regulation of specific abnormal calcium signals in the hippocampal CA1 and primary cortex M1 alleviates the progression of temporal lobe epilepsy

Temporal lobe epilepsy is a multifactorial neurological dysfunction syndrome that is refractory,resistant to antiepileptic drugs,and has a high recurrence rate.The pathogenesis of temporal lobe epilepsy is complex and is not fully understood.Intracellular calcium dynamics have been implicated in temporal lobe epilepsy.However,the effect of fluctuating calcium activity in CA1 pyramidal neurons on temporal lobe epilepsy is unknown,and no longitudinal studies have investigated calcium activity in pyramidal neurons in the hippocampal CA1 and primary motor cortex M1 of freely moving mice.In this study,we used a multichannel fiber photometry system to continuously record calcium signals in CA1 and M1 during the temporal lobe epilepsy process.We found that calcium signals varied according to the grade of temporal lobe epilepsy episodes.In particular,cortical spreading depression,which has recently been frequently used to represent the continuously and substantially increased calcium signals,was found to correspond to complex and severe behavioral characteristics of temporal lobe epilepsy ranging from gradeⅡto gradeⅤ.However,vigorous calcium oscillations and highly synchronized calcium signals in CA1 and M1 were strongly related to convulsive motor seizures.Chemogenetic inhibition of pyramidal neurons in CA1 significantly attenuated the amplitudes of the calcium signals corresponding to gradeⅠepisodes.In addition,the latency of cortical spreading depression was prolonged,and the above-mentioned abnormal calcium signals in CA1 and M1 were also significantly reduced.Intriguingly,it was possible to rescue the altered intracellular calcium dynamics.Via simultaneous analysis of calcium signals and epileptic behaviors,we found that the progression of temporal lobe epilepsy was alleviated when specific calcium signals were reduced,and that the end-point behaviors of temporal lobe epilepsy were improved.Our results indicate that the calcium dynamic between CA1 and M1 may reflect specific epileptic behaviors corresponding to different grades.Furthermore,the selective regulation of abnormal calcium signals in CA1 pyramidal neurons appears to effectively alleviate temporal lobe epilepsy,thereby providing a potential molecular mechanism for a new temporal lobe epilepsy diagnosis and treatment strategy.

Exploring the role of interleukin-6 receptor blockade in epilepsy and associated neuropsychiatric conditions through a mendelian randomization study

BACKGROUND The interplay between inflammation,immune dysregulation,and the onset of neurological disorders,including epilepsy,has become increasingly recognized.Interleukin(IL)-6,a pro-inflammatory cytokine,is suspected to not only mediate traditional inflammatory pathways but also contribute to neuroinflammatory responses that could underpin neuropsychiatric symptoms and broader psychiatric disorders in epilepsy patients.The role of IL-6 receptor(IL6R)blockade presents an intriguing target for therapeutic intervention due to its potential to attenuate these processes.neuropsychiatric conditions due to neuroinflammation.METHODS Mendelian randomization(MR)analysis employing single nucleotide poly-morphisms(SNPs)in the vicinity of the IL6R gene(total individuals=408225)was used to evaluate the putative causal relationship between IL6R blockade and epilepsy(total cases/controls=12891/312803),focal epilepsy(cases/controls=7526/399290),and generalized epilepsy(cases/controls=1413/399287).SNP weights were determined by their effect on C-reactive protein(CRP)levels and integrated using inverse variance-weighted meta-analysis as surrogates for IL6R effects.To address potential outlier and pleiotropic influences,sensitivity analyses were conducted employing a variety of MR methods under different modeling assumptions.RESULTS The genetic simulation targeting IL6R blockade revealed a modest but significant reduction in overall epilepsy risk[inverse variance weighting:Odds ratio(OR):0.827;95%confidence interval(CI):0.685-1.000;P=0.05].Subtype analysis showed variability,with no significant effect observed in generalized,focal,or specific childhood and juvenile epilepsy forms.Beyond the primary inflammatory marker CRP,the findings also suggested potential non-inflammatory pathways mediated by IL-6 signaling contributing to the neurobiological landscape of epilepsy,hinting at possible links to neuroinflammation,psychiatric symptoms,and associated mental disorders.CONCLUSION The investigation underscored a tentative causal relationship between IL6R blockade and decreased epilepsy incidence,likely mediated via complex neuroinflammatory pathways.These results encouraged further in-depth studies involving larger cohorts and multifaceted psychiatric assessments to corroborate these findings and more thoroughly delineate the neuro-psychiatric implications of IL-6 signaling in epilepsy.The exploration of IL6R blockade could herald a novel therapeutic avenue not just for seizure management but also for addressing the broader psychiatric and cognitive disturbances often associated with epilepsy.

Effects of intensive psychological intervention on treatment compliance,psychological status,and quality of life of patients with epilepsy

BACKGROUND Epilepsy is a nervous system disease characterized by recurrent attacks,a long disease course,and an unfavorable prognosis.It is associated with an enduring therapeutic process,and finding a cure has been difficult.Patients with epilepsy are predisposed to adverse moods,such as resistance,anxiety,nervousness,and anxiety,which compromise treatment compliance and overall efficacy.AIM To explored the influence of intensive psychological intervention on treatment compliance,psychological status,and quality of life(QOL)of patients with epilepsy.METHODS The clinical data of 105 patients with epilepsy admitted between December 2019 and July 2023 were retrospectively analyzed,including those of 50 patients who underwent routine intervention(control group)and 55 who underwent intensive psychological intervention(research group).Treatment compliance,psychological status based on the Self-Rating Anxiety Scale(SAS)and Depression Scale Self-Rating Depression Scale(SDS)scores,hope level assessed using the Herth Hope Scale(HHS),psychological resilience evaluated using the Psychological Resilience Scale,and QOL determined using the QOL in Epilepsy-31 Inventory(QOLIE-31)were comparatively analyzed.RESULTS Treatment compliance in the research group was 85.5%,which is significantly better than the 68.0%of the control group.No notable intergroup differences in preinterventional SAS and SDS scores were identified(P>0.05);however,after the intervention,the SAS and SDS scores decreased significantly in the two groups,especially in the research group(P<0.05).The two groups also exhibited no significant differences in preinterventional HHS,Connor-Davidson Resilience Scale(CD-RISC),and QOLIE-31 scores(P>0.05).After 6 months of intervention,the research group showed evidently higher HHS,CD-RISC,tenacity,optimism,strength,and QOLIE-31 scores(P<0.05).CONCLUSION Intensive psychological intervention enhances treatment compliance,psychological status,and QOL of patients with epilepsy.

Intrinsic correlation between the generalized phase equilibrium condition and mechanical behaviors in hydrate-bearing sediments

The phase equilibrium and mechanical behaviors of natural gas hydrate-bearing sediment are essential for gas recovery from hydrate reservoirs.In heating closed systems,the temperature-pressure path of hydrate-bearing sediment deviates from that of pure bulk hydrate,reflecting the porous media effect in phase equilibrium.A generalized phase equilibrium equation was established for hydrate-bearing sediments,which indicates that both capillary and osmotic pressures cause the phase equilibrium curve to shift leftward on the temperature-pressure plane.In contrast to bulk hydrate,hydrate-bearing sediment always contains a certain amount of unhydrated water,which keeps phase equilibrium with the hydrate within the hydrate stability field.With changes in temperature and pressure,a portion of pore hydrate and unhydrated water may transform into each other,affecting the shear strength of hydrate-bearing sediment.A shear strength model is proposed to consider not only hydrate saturation but also the change in temperature and pressure of hydrate-bearing sediment.The model is validated by experimental data with various hydrate saturation,temperature and pressure conditions.The deformation induced by partial dissociation was studied through depressurization tests under constant effective stress.The reduction in gas pressure within the hydrate stability field indeed caused sediment deformation.The dissociation-induced deformation can be reasonably estimated as the difference in volume between hydrate-bearing and hydrate-free sediments from the compression curves.

3D digital-image correlation insight into generalized relaxation behavior of sandstone under stress and pore pressure coupling

The occurrence of geological hazards and the instability of geotechnical engineering structures are closely related to the time-dependent behavior of rock.However,the idealization boundary condition for constant stress in creep or constant strain in relaxation is not usually attained in natural geological systems.Therefore,generalized relaxation tests that explore the simultaneous changes of stress and strain with time under different stress levels with constant pore-water pressure are conducted in this study.The results show that in area I,area II,and area III,the stress and strain both change synchronously with time and show similar evolutionary laws as the strain-time curve for creep or the stress-time curve for relaxation.When the applied stress level surpasses the sci or scd threshold,the variations in stress and strain and their respective rates of change exhibit a significant increase.The radial deformation and its rate of change exhibit greater sensitivity in response to stress levels.The apparent strain deforms homogeneously at the primary stage,and subsequently,gradually localizes due to the microcrack development at the secondary stage.Ultimately,interconnection of the microcracks causes the formation of a shear-localization zone at the tertiary stage.The strain-time responses inside and outside the localization zone are characterized by local strain accumulation and inelastic unloading during the secondary and tertiary stages,respectively.The width of the shear-localization zone is found to range from 4.43 mm to 7.08 mm and increased with a longer time-to-failure.Scanning electron microscopy(SEM)reveals a dominant coalescence of intergranular cracks on the fracture surface,and the degree of physiochemical deterioration caused by water-rock interaction is more severe under a longer lifetime.The brittle sandstone’s time-dependent deformation is essentially controlled by microcrack development during generalized relaxation,and its expectancy-life is determined by its initial microstructural state and the rheological path.