Prelimbic cortical pyramidal neurons to ventral tegmental area projections promotes arousal from sevoflurane anesthesia.

AIMS: General anesthesia has been used in surgical procedures for approximately 180 years, yet the precise mechanism of anesthetic drugs remains elusive. There is significant anatomical connectivity between the ventral tegmental area (VTA) and the prelimbic cortex (PrL). Projections from VTA dopaminergic neurons (VTADA ) to the PrL play a role in the transition from sevoflurane anesthesia to arousal. It is still uncertain whether the prelimbic cortex pyramidal neuron (PrLPyr ) and its projections to VTA (PrLPyr -VTA) are involved in anesthesia-arousal regulation. METHODS: We employed chemogenetics and optogenetics to selectively manipulate neuronal activity in the PrLPyr -VTA pathway. Electroencephalography spectra and burst-suppression ratios (BSR) were used to assess the depth of anesthesia. Furthermore, the loss or recovery of the righting reflex was monitored to indicate the induction or emergence time of general anesthesia. To elucidate the receptor mechanisms in the PrLPyr -VTA projection's impact on anesthesia and arousal, we microinjected NMDA receptor antagonists (MK-801) or AMPA receptor antagonists (NBQX) into the VTA. RESULTS: Our findings show that chemogenetic or optogenetic activation of PrLPyr neurons prolonged anesthesia induction and promoted emergence. Additionally, chemogenetic activation of the PrLPyr -VTA neural pathway delayed anesthesia induction and promoted anesthesia emergence. Likewise, optogenetic activation of the PrLPyr -VTA projections extended the induction time and facilitated emergence from sevoflurane anesthesia. Moreover, antagonizing NMDA receptors in the VTA attenuates the delayed anesthesia induction and promotes emergence caused by activating the PrLPyr -VTA projections. CONCLUSION: This study demonstrates that PrLPyr neurons and their projections to the VTA are involved in facilitating emergence from sevoflurane anesthesia, with the PrLPyr -VTA pathway exerting its effects through the activation of NMDA receptors within the VTA.

Adaptive Event-Triggered Consensus of Multi-Agent Systems in Sense of Asymptotic Convergence.

In this paper, the asymptotic consensus control of multi-agent systems with general linear agent dynamics is investigated. A neighbor-based adaptive event-triggering strategy with a dynamic triggering threshold is proposed, which leads to a fully distributed control of the multi-agent system, depending only on the states of the neighboring agents at triggering moments. By using the Lyapunov method, we prove that the states of the agents converge asymptotically. In addition, the proposed event-triggering strategy is proven to exclude Zeno behavior. The numerical simulation results illustrate that the agent states achieve consensus in sense of asymptotic convergence. Furthermore, the proposed strategy is shown to be scalable in case of variable agent numbers.

Ventrolateral periaqueductal gray GABAergic neurons promote arousal of sevoflurane anesthesia through cortico-midbrain circuit.

The mechanism of general anesthesia remains elusive. The ventrolateral periaqueductal gray (vlPAG) in the midbrain regulates sleep and awake states. However, the role of vlPAG and its circuits in anesthesia is unclear. We utilized opto/chemogenetics, righting reflex, and electroencephalographic recording to assess consciousness changes. We employed fiber photometry to measure the activity of neurons and neurotransmitters. As a result, photometry recording showed that the activity of GABA neurons in vlPAG decreased during sevoflurane anesthesia and was reactivated after anesthesia. Activating GABAergic neurons in vlPAG promoted arousal during anesthesia, while inhibiting them delayed this process. Furthermore, medial prefrontal cortex (mPFC) to vlPAG pyramidal neurons projections and vlPAG to ventral tegmental area (VTA) GABAergic projections played a prominent role in the anesthesia-awake transition. GABA neurotransmitter activity of VTA synchronized with mPFC-vlPAG pyramidal neuron projections. Therefore, the cortico-midbrain circuits centered on vlPAG GABAergic neurons exert an arousal-promoting effect during sevoflurane anesthesia.

Mental health changes in elderly patients undergoing non-cardiac surgery during the COVID-19 pandemic in China.

BACKGROUND: The COVID-19 pandemic has a heavy impact on the mental health of elderly surgical patients worldwide. In particular, the elderly patients faced considerable psychological stress due to various environmental and medical factors during the outbreak. This study aims to examine changes in mental health trends among non-cardiac surgical patients aged 65 and above in China during the COVID-19 pandemic. METHODS: This multi-center, convenient sampling, longitudinal observational study was conducted from April 1, 2020 to April 30, 2022. Primary outcome was the prevalence of postoperative depression. Secondary outcome was the prevalence of postoperative anxiety. Follow-up was conducted separately at 7 days and 30 days after surgery. Depression symptoms were assessed using the Patient Health Questionnaire 9 (PHQ-9) scale. Anxiety symptoms were assessed using Generalized Anxiety Disorder-7 (GAD-7) scale, with scores of ≥5 defining positive depression or anxiety symptoms. Multivariate logistic regression analysis was used to investigate risk factors of mental health status in more elderly patients undergoing non-cardiac surgery. RESULTS: A total of 4639 patients were included, of whom 2279 (46.0 %) were male, 752 (15.2 %) were over the age of 75, and 4346 (93.7 %) were married. The monthly prevalence trends demonstrated that compared to the outbreak period, a significant reduction in the prevalence of depression and anxiety symptoms in elderly patients who underwent surgery during the post-pandemic period. In post-pandemic period, a statistically significant decrease in the prevalence of all severity depression and anxiety patients was noted at the 7-day follow-up, but no significant decrease was observed for severe depression and anxiety in the 30-day follow-up. In COVID-19 low-risk area, a significant overall decrease in prevalence of mental health was observed during the post-pandemic period compared to the outbreak period, including 7-day depression, 7-day anxiety, 30-day depression, and 30-day anxiety (all with P < 0.001). Female and patients with ≥2 comorbidities appeared to be more susceptible to postoperative depression and anxiety during the pandemic. LIMITATION: The absence of data from the early days of the COVID-19 outbreak. CONCLUSIONS: This study analyzed the prevalence of depression and anxiety in elderly non-cardiac patients during and after the COVID-19 pandemic, focusing on dimensions such as severity, risk-areas, gender, and comorbidity. Our findings revealed a significant decrease in the prevalence of depression and anxiety in elderly surgery patients during the post-pandemic period.

Prognostic Nutritional Index (PNI) as a potential predictor and intervention target for perioperative ischemic stroke: a retrospective cohort study.

BACKGROUND: The prognostic nutritional index (PNI) is a nutritional indicator and predictor of various diseases. However it is unclear whether PNI can be a predictor of perioperative ischemic stroke. This study aims to evaluate the association of the preoperative PNI and ischemic stroke in patients undergoing non-cardiac surgery. METHODS: The retrospective cohort study included patients who underwent noncardiac surgery between January 2008 and August 2019. The patients were divided into PNI ≥ 38.8 and PNI < 38.8 groups according to the cut-off value of PNI. Univariate and multivariate logistic regression analyses were performed to explore the association between PNI and perioperative ischemic stroke. Subsequently, propensity score matching (PSM) analysis was performed to eliminate the confounding factors of covariates and further validate the results. Subgroup analyses were completed to assess the predictive utility of PNI for perioperative ischemic stroke in different groups. RESULTS: Amongst 221,542 hospitalized patients enrolled, 485 (0.22%) experienced an ischemic stroke within 30 days of the surgery, 22.1% of patients were malnourished according to PNI < 38.8, and the occurrence of perioperative ischemic stroke was 0.34% (169/49055) in the PNI < 38.8 group. PNI < 38.8 was significantly associated with an increased incidence of perioperative ischemic stroke whether in univariate logistic regression analysis (OR = 1.884, 95% CI: 1.559-2.267, P < 0.001) or multivariate logistic regression analysis (OR = 1.306, 95% CI: 1.061-1.602, P = 0.011). After PSM analysis, the ORs of PNI < 38.8 group were 1.250 (95% CI: 1.000-1.556, P = 0.050) and 1.357 (95% CI: 1.077-1.704, P = 0.009) in univariate logistic regression analysis and multivariate logistic regression analysis respectively. The subgroup analysis indicated that reduced PNI was significantly associated to an increased risk of perioperative ischemic stroke in patients over 65 years old, ASA II, not taking aspirin before surgery, without a history of stroke, who had neurosurgery, non-emergency surgery, and were admitted to ICU after surgery. CONCLUSIONS: Our study indicates that low preoperative PNI is significantly associated with a higher incidence of ischemic stroke in patients undergoing non-cardiac surgery. Preoperative PNI, as a preoperative nutritional status evaluation index, is an independent risk factor useful to predict perioperative ischemic stroke risk, which could be used as an intervenable preoperative clinical biochemical index to reduce the incidence of perioperative ischemic stroke.

Insulin alleviates lipopolysaccharide-induced cognitive impairment via inhibiting neuroinflammation and ferroptosis.

Neuroinflammation is regarded to be a key mediator in cerebral diseases with attendant cognitive decline. Ferroptosis, characterized by iron-dependent lipid peroxidation, participates in neuroinflammation and cognitive impairment. Recent studies have revealed insulin's neuroprotective effects and involvement in the regulation of numerous central functions. But the effect of insulin on cognitive impairment induced by neuroinflammation has been rarely explored. In this study, we constructed a cognitive impairment model by intracerebroventricular injection of lipopolysaccharide (LPS) and a single dosage of insulin was mixed in the LPS solution to explore the potential mechanisms through which insulin treatment could improve LPS-induced cognitive dysfunction. At 24 h after treatment, we found that insulin treatment significantly improved LPS-induced cognitive decline, neuronal injuries, and blood-brain barrier (BBB) disruption. Insulin treatment could also inhibit the LPS-induced activation of microglia and astrocytes, and the release of tumor necrosis factor-α (TNF-α) and interleukin-1ß (IL-1ß) in the hippocampus. Furthermore, insulin treatment inhibited LPS-induced ferroptosis in the hippocampus by decreasing iron accumulation levels, regulating ferroptosis-related proteins including transferrin, glutathione peroxidase 4 (GPX4), ferritin heavy chin 1 (FTH1) and cystine/glutamate antiporter (xCT), inhibiting oxidative stress injuries and lipid peroxidation in the hippocampus. In conclusion, our finding that insulin treatment could alleviate LPS-induced cognitive impairment by inhibiting neuroinflammation and ferroptosis provides a new potential therapeutic method to ameliorate cognitive decline.

Association of triglyceride-glucose index with myocardial injury post-stroke in older patients with first-ever ischemic stroke.

BACKGROUND: Myocardial injury post-stroke is a common sequela of acute stroke. Triglyceride-glucose index (TyG index), a valuable surrogate indicator of insulin resistance, has been suggested to be closely related to cardiovascular outcomes. However, it is unknown whether the TyG index is independently associated with a higher risk of myocardial injury post-stroke. We therefore investigated the longitudinal association between TyG index and risk of myocardial injury post-stroke in older patients with first-ever ischemic stroke and no prior cardiovascular comorbidities. METHODS: We included older patients with first-ever ischemic stroke and no prior cardiovascular comorbidities between January 2021 to December 2021. The individuals were stratified into low and high TyG index groups according to the optimal cutoff value with TyG index. We performed logistic regression analysis, propensity score matching (PSM) analysis, restricted cubic spline analysis, and subgroup analyses to explore the longitudinal association between TyG index and risk of myocardial injury post-stroke. RESULTS: We included 386 individuals with a median age of 69.8 years (interquartile range: 66.6, 75.3). The optimal TyG index cut-off for predicting myocardial injury post-stroke was 8.9 (sensitivity 67.8%; specificity 75.5%; area under curve 0.701). Multivariate logistic regression analysis revealed that the risk of genesis of myocardial injury post-stroke increased with elevated TyG index (odds ratio [OR], 2.333; 95% confidence interval [CI], 1.201-4.585; P = 0.013). Furthermore, all covariates were well balanced between the two groups. The longitudinal association between TyG index and myocardial injury post-stroke remained significantly robust (OR: 2.196; 95% CI: 1.416-3.478; P < 0.001) after PSM adjustment. CONCLUSION: Individuals with an elevated TyG index were more susceptible to having an increased risk of myocardial injury post-stroke. TyG index thus might be served as a complementary approach for optimized-for-risk stratification in older patients with first-ever ischemic stroke and no prior cardiovascular comorbidities.

Risk Factor Analysis and a Predictive Model of Postoperative Depressive Symptoms in Elderly Patients Undergoing Video-Assisted Thoracoscopic Surgery.

Among the elderly, depression is one of the most common mental disorders, which seriously affects their physical and mental health and quality of life, and their suicide rate is particularly high. Depression in the elderly is strongly associated with surgery. In this study, we aimed to explore the risk factors and establish a predictive model of depressive symptoms 1 month after video-assisted thoracoscopic surgery (VATS) in elderly patients. The study participants included 272 elderly patients (age > 65 years) undergoing VATS from April 2020 to May 2021 at 1 of 18 medical centers in China. The patients were divided into a depression group and a nondepression group according to the Chinese version of the nine-item Patient Health Questionnaire (PHQ-9). The patients' pre- and postoperative characteristics and questionnaires were collected and compared. Then, binary logistic regression was used to determine the risk factors that affect postoperative depressive symptoms, and the predictive model was constructed. The prediction efficiency of the model was evaluated by drawing the receiver operating characteristic curve (ROC), and the area under the curve (AUC) was calculated to evaluate the value of the predictive model. Among all of the included patients, 16.54% (45/272) suffered from depressive symptoms after VATS. The results of the univariate analysis showed that body mass index (BMI), chronic pain, leukocyte count, fibrinogen levels, prothrombin time, ASA physical status, infusion volume, anxiety, sleep quality, and postoperative pain were related to postoperative depressive symptoms (all p < 0.05). The results of multivariate logistic regression analysis showed that a high fibrinogen level (OR = 2.42), postoperative anxiety (OR = 12.05), poor sleep quality (OR = 0.61), and pain (OR = 2.85) were risk factors of postoperative depressive symptoms. A predictive model was constructed according to the regression coefficient of each variable, the ROC curve was drawn, and the AUC value was calculated to be 0.889. The prediction model may help medical personnel identify older patients at risk of developing depressive disorders associated with VATS and may be useful for clinical purposes.

Intraoperative dexmedetomidine on postoperative pain in gastrointestinal surgery: an observational study.

BACKGROUND: Dexmedetomidine (DEX) is widely used for adjuvant sedation and analgesia in gastrointestinal surgeries. The authors aimed to reassess the effects of intraoperative DEX on acute pain by comprehensive analysis of the multiple dimensions of pain. MATERIALS AND METHODS: In this multicentre cohort study, patients undergoing gastrointestinal surgeries were prospectively enrolled in the China Acute Postoperative Pain Study. Patients were divided into DEX and non-DEX groups based on whether DEX was used during surgery. Patient satisfaction with pain treatment (rated on a numeric rating score, 0-10) and other pain-related outcomes were evaluated using the International Pain Outcome Questionnaire on the first postoperative day. The effects of intraoperative DEX were analyzed using logistic or linear regression for dichotomous or continuous variables, respectively. Propensity score matching and subgroup analyses were performed to appraise the correlation between intraoperative DEX and postoperative pain outcomes. RESULTS: Of the 1260 patients eligible for analysis, 711 (56.4%) received intraoperative DEX. Propensity score matching resulted in 415 patients in each group. Intraoperative DEX was associated with higher patient satisfaction (ß: 0.556; 95% CI: 0.366-0.745), and a decrease in the percentage of time spent in severe pain (ß: -0.081; 95% CI: -0.104- -0.058), anxiety (odds ratio: 0.394; 95% CI: 0.307-0.506), helplessness (odds ratio: 0.539; 95% CI: 0.411-0.707), and postoperative opioid consumption (ß: -16.342; 95% CI: -27.528- -5.155). CONCLUSIONS: Intraoperative DEX was associated with the prognosis of acute postoperative pain in multiple aspects in patients undergoing major gastrointestinal surgery, including increased patient satisfaction, and a reduction in the duration of severe pain, postoperative anxiety and helplessness, and postoperative opioid consumption. Future studies to determine the dose and timing of DEX administration on pain-related outcomes are warranted.

Assessing Hemorrhagic Shock Severity Using the Second Heart Sound Determined from Phonocardiogram: A Novel Approach.

Introduction: Hemorrhagic shock (HS) is a severe medical emergency. Early diagnosis of HS is important for clinical treatment. In this paper, we report a flexible material-based heart sound monitoring device which can evaluate the degree of HS through a phonocardiogram (PCG) change. Methods: Progressive hemorrhage treatments (H1, H2, and H3 stage) were used in swine to build animal models. The PCG sensor was mounted on the chest of the swine. Routine monitoring was used at the same time. Results: This study showed that arterial blood pressure decreased significantly from the H1 phase, while second heart sound amplitude (S2A) and energy (S2E) decreased significantly from the H2 phase. Both S2A and S2E correlated well with BP (p < 0.001). The heart rate, pulse pressure variation and serum hemoglobin level significantly changed in the H3 stage (p < 0.05). Discussion: The change of second heart sound (S2) was at the H2 stage and was earlier than routine monitoring methods. Therefore, PCG change may be a new indicator for the early detection of HS severity.

Insights into the removal of organic contaminants by calcium sulfite activation with Fe(III): Performance, kinetics, and mechanisms.

S(IV)-based advanced oxidation process has been applied for contaminants remediation. However, as a traditional source of sulfite (SO32-), Na2SO3 is extremely soluble in water, resulting in a high concentration of SO32- to quench the generated reactive oxygen species (ROS). In this work, CaSO3 was introduced instead of Na2SO3 for its slow-released SO32- ability and Fe(III)/CaSO3 system was established for the removal of trichloroethylene (TCE) and other organic contaminants. The degradation efficiency of TCE reached 94.0% and TCE could be completely dechlorinated and mineralized, while the removal of other contaminants was all over 85.0% at the optimal tested conditions. Through EPR detection, ROS scavenging and probe tests, and quantification of ROS amounts, it was concluded that the dominant ROS in Fe(III)/CaSO3 system were SO4-· and 1O2, of which the transformation mechanism of SO4-· to 1O2 was revealed and demonstrated comprehensively. The synergistic contaminants degradation performance in different sulfur-iron-containing systems and in the presence of oxidants was evaluated. The effects of various solution conditions were assessed and Fe(III)/CaSO3 system was of higher resistance on complex solution matrixes, suggesting the broad-spectrum and application perspective for the remediation of complex contaminants in actual water.

Insights into the role of nanoscale zero-valent iron in Fenton oxidation and its application in naphthalene degradation from water and slurry systems.

Few researches have focused on the role of nanoscale zero-valent iron (nZVI) in Fenton-like process for polycyclic aromatic hydrocarbons (PAHs) removal. In this study, the naphthalene (NAP) degradation tests in ultrapure water showed that nZVI addition could enhance NAP degradation from 79.7% to 99.0% in hydrogen peroxide (H2 O2 )/Fe (II)/nZVI/NAP system at the molar ratio of 10/5/3/1, showing the excellent role of nZVI in promoting NAP removal. Multiple linear regression analysis found that the correlation coefficient between H2 O2 consumption and NAP degradation was converted from -9.17 to 0.48 with nZVI and 1-mM H2 O2 , indicating that nZVI could decompose H2 O2 more beneficially for NAP degradation. Multiple Fe (II)-dosing and iron leaching tests revealed that nZVI could gently liberate Fe (II) and promote Fe (II)/Fe (III) redox cycle to enhance the NAP degradation. When the H2 O2 /Fe (II)/nZVI/NAP molar ratios of 10/5/3/1 and 50/25/15/1 were applied in the simulated NAP contaminated actual groundwater and soil slurry, respectively, 75.0% and 82.9% of NAP removals were achieved. Based on the major degradation intermediates detected by GC/MS, such as 1,4-naphthalenedione, cinnamaldehyde, and o-phthalaldehyde, three possible NAP degradation pathways were proposed. This study provided the applicable potential of nZVI in Fenton process for PAHs contaminated groundwater and soil remediation. PRACTITIONER POINTS: nZVI enhanced the NAP degradation in Fenton-like process. Three schemes of NAP degradation pathway were proposed. nZVI performed well in the remediation of the simulated NAP contamination.

Efficient naphthalene degradation in FeS2-activated nano calcium peroxide system: Performance and mechanisms.

Naphthalene (NAP) has received increasing concern due to frequent detection in groundwater and harm to humans. In this study, FeS2 was selected as a novel catalyst to activate nano calcium peroxide (nCP) for NAP degradation. Batch experiments were conducted in a 250 mL glass reactor containing 0.1 mM NAP solution to investigate the effect of reagents dosage, pH, air conditions (with or without N2 purge), and different solution matrixes on NAP degradation. Scavenging tests, electron paramagnetic resonance (EPR) spectrum, and radical probe tests were conducted to identify the main radicals. Results indicated that over 96% NAP was removed in a wide pH range (3.0-9.0) within 180 min at optimal dosage of nCP = 1.0 mM and FeS2 = 5.0 g L-1 in nCP/FeS2 system. Aerobic condition was more beneficial to NAP degradation and the system could tolerate complex solution conditions. Moreover, HO• was determined to be responsible for NAP degradation. NAP degradation intermediates were detected by gas chromatography-mass spectrometry (GC-MS) and the possible degradation pathways were revealed. Finally, the efficient degradation of other organic pollutants confirmed the broad-spectrum reactivity of the nCP/FeS2 system. Overall, these findings strongly demonstrated the potential applicability of nCP/FeS2 system in remediating organic contaminated groundwater.

Common Variants of the OPG gene Are Associated with Osteoporosis Risk: A Meta-Analysis.

Background: The RANKL/RANK/OPG signaling pathway plays a critical role in osteoclastogenesis and bone remodeling. The associations between sequence variants of the osteoprotegerin (OPG) gene and osteoporosis risk have been widely investigated but remain inconclusive. Objective: We performed a meta-analysis to evaluate the associations between OPG gene variants and osteoporosis risk. Methods: We searched electronic databases and included studies meeting inclusion criteria. The genetic associations of four common OPG variants, A163G, T245G, T950C, and G1181C, with osteoporosis risk were explored. Pooled odds ratios (OR) and 95% confidence intervals (95% CI) were calculated for multiple genetic models. Subgroup analyses including ethnicity, gender, menopausal status, sample size, and control source were also performed. Results: Twenty-six studies comprising 4879 osteoporosis cases and 5708 controls were included. The A163G variant was found to be significantly associated with an increased risk of osteoporosis under both the allelic (G vs. A: OR = 1.45, 95% CI 1.29-1.64, p < 0.001) and dominant models (GG+GA vs. AA: OR = 1.48, 95% CI 1.29-1.70, p < 0.001). Significant associations were also found between the T245G variant and osteoporosis risk. In addition, we observed a reduced risk of osteoporosis in women with the CC genotype at T950C (OR = 0.76, 95% CI 0.64-0.89, p = 0.001) and among Caucasians with the GG or CG genotypes at the G1181C locus (OR = 0.78, 95% CI 0.64-0.94, p = 0.010). In postmenopausal women, only the GG/GA genotypes at the A163G variant were more predisposed to osteoporosis (OR = 1.31, 95% CI 1.00-1.71), whereas CC/CG carriers of G1181C locus may have reduced risk (OR = 0.83, 95% CI 0.66-1.03). Conclusions: Common variants of the OPG gene are associated with osteoporosis risk, especially in the Caucasian population and in the female subgroup. These genetic markers could potentially be used as predictive markers for osteoporosis.

Development of Rapid and High-Precision Colorimetric Device for Organophosphorus Pesticide Detection Based on Microfluidic Mixer Chip.

The excessive pesticide residues in cereals, fruit and vegetables is a big threat to human health, and it is necessary to develop a portable, low-cost and high-precision pesticide residue detection scheme to replace the large-scale laboratory testing equipment for rapid detection of pesticide residues. In this study, a colorimetric device for rapid detection of organophosphorus pesticide residues with high precision based on a microfluidic mixer chip was proposed. The microchannel structure with high mixing efficiency was determined by fluid dynamics simulation, while the corresponding microfluidic mixer chip was designed. The microfluidic mixer chip was prepared by a self-developed liquid crystal display (LCD) mask photo-curing machine. The influence of printing parameters on the accuracy of the prepared chip was investigated. The light source with the optimal wavelength of the device was determined by absorption spectrum measurement, and the relationship between the liquid reservoir depth and detection limit was studied by experiments. The correspondence between pesticide concentration and induced voltage was derived. The minimum detection concentration of the device could reach 0.045 mg·L-1 and the average detection time was reduced to 60 s. The results provide a theoretical and experimental basis for portable and high-precision detection of pesticide residues.

Plasmonic topological quasiparticle on the nanometre and femtosecond scales.

At the interface of classical and quantum physics, the Maxwell and Schrödinger equations describe how optical fields drive and control electronic phenomena to enable lightwave electronics at terahertz or petahertz frequencies and on ultrasmall scales1-5. The electric field of light striking a metal interacts with electrons and generates light-matter quasiparticles, such as excitons6 or plasmons7, on an attosecond timescale. Here we create and image a quasiparticle of topological plasmonic spin texture in a structured silver film. The spin angular momentum components of linearly polarized light interacting with an Archimedean coupling structure with a designed geometric phase generate plasmonic waves with different orbital angular momenta. These plasmonic fields undergo spin-orbit interaction and their superposition generates an array of plasmonic vortices. Three of these vortices can form spin textures that carry non-trivial topological charge8 resembling magnetic meron quasiparticles9. These spin textures are localized within a half-wavelength of light, and exist on the timescale of the plasmonic field. We use ultrafast nonlinear coherent photoelectron microscopy to generate attosecond videos of the spatial evolution of the vortex fields; electromagnetic simulations and analytic theory confirm the presence of plasmonic meron quasiparticles. The quasiparticles form a chiral field, which breaks the time-reversal symmetry on a nanometre spatial scale and a 20-femtosecond timescale (the 'nano-femto scale'). This transient creation of non-trivial spin angular momentum topology pertains to cosmological structure creation and topological phase transitions in quantum matter10-12, and may transduce quantum information on the nano-femto scale13,14.