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A growing number of clinical and animal studies suggest that the nucleus accumbens (NAc), especially the shell, is involved in the pathogenesis of temporal lobe epilepsy (TLE). However, the role of parvalbumin (PV) GABAergic neurons in the NAc shell involved in TLE is still unclear. In this study, we induced a spontaneous TLE model by intrahippocampal administration of kainic acid (KA), which generally induce acute seizures in first 2 h (acute phase) and then lead to spontaneous recurrent seizures after two months (chronic phase). We found that chemogenetic activation of NAc shell PV neurons could alleviate TLE seizures by reducing the number and period of focal seizures (FSs) and secondary generalized seizures (sGSs), while selective inhibition of PV exacerbated seizure activity. Ruby-virus mapping results identified that the hippocampus (ventral and dorsal) is one of the projection targets of NAc shell PV neurons. Chemogenetic activation of the NAc-Hip PV projection fibers can mitigate seizures while inhibition has no effect on seizure ictogenesis. In summary, our findings reveal that PV neurons in the NAc shell could modulate the seizures in TLE via a long-range NAc-Hip circuit. All of these results enriched the investigation between NAc and epilepsy, offering new targets for future epileptogenesis research and precision therapy. • Chemogenetic activation of PV (+) neurons in the NAc shell attenuates seizures. • Chemogenetic inhibition of NAc shell PV (+) neurons aggravates seizures. • The ventral and dorsal hippocampus is innervated by the NAc PV projections. • Chemogenetic activation of the NAc-Hippocampal PV projection fibers also has an antiepileptic effect. [ABSTRACT FROM AUTHOR]

• Pooled reported prevalence in IGE is 27% with a mean follow-up of 14 years. • Psychiatric comorbidities, combined three seizure types, the presence of absence seizure, generalized polyspike trains, status epilepticus, and catamenial epilepsy significantly increase the odds of drug resistance. • Further prospective cohort studies are needed to investigate the clinical and EEG factors to help complete the prognostic guidelines. Idiopathic generalized epilepsy (IGE) is a common epilepsy syndrome with early age onset and generally good seizure outcomes. This study aims to determine the incidence and predictive risk factors for drug-resistant IGE. We systematically searched three databases (PubMed, Embase, and Cochrane Library) in November 2022 and included 12 eligible studies which reported long-term outcomes (mean = 14.05) after antiseizure medications (ASMs) from 2001 to 2020. We defined drug resistance as the persistence of any seizure despite ASMs treatment (whether as monotherapies or in combination) given the criteria of drug resistance varied in original studies. A random-effects model was used to evaluate the prevalence of refractory IGE. Studies reporting potential poor prognostic factors were included for subsequent subgroup meta-analysis. The pooled prevalence of drug resistance in IGE cohorts was 27% (95% CI: 0.19–0.36). Subgroup analysis of the risk factors revealed that the psychiatric comorbidities (odds ratio (OR): 4.87, 95% confidence interval (CI): 2.97–7.98), combined three seizure types (absences, myoclonic jerks, and generalized tonic-clonic seizures) (OR: 5.37, 95% CI: 3.16–9.13), the presence of absence seizure (OR: 4.38, 95% CI: 2.64–7.28), generalized polyspike trains (GPT) (OR: 4.83, 95% CI: 2.42–9.64), sex/catamenial epilepsy (OR: 3.25, 95% CI: 1.97–5.37), and status epilepticus (OR: 5.94, 95% CI: 2.23–15.85) increased the risk of poor prognosis. Other factors, including age onset, family history, and side effects of ASMs, were insignificantly associated with a higher incidence of refractory IGE. Drug resistance is a severe complication of IGE. Further standardized research about clinical and electroencephalography factors is warranted. [ABSTRACT FROM AUTHOR]

Highlights: [•] This is the structure of GH131 family enzyme in complex with polysaccharide. [•] The broadened substrate binding cleft may explain the substrate diversity. [•] The hydrolysis of GH131 family enzyme may perform via an inverting mechanism. [ABSTRACT FROM AUTHOR]

The multi-clearances of breaking type steering trapezoidal mechanism joints influences vehicle steering stability. Hence, to ascertain the influence of clearance value on steering stability, this paper takes the steering mechanism of a certain vehicle type as a prototype that can be simplified into a planar six-bar linkage, then establishes the system dynamic differential equations after considering the two clearances of tie rods and the steering knuckle arms. The influence of the clearance parameters on the movement stability of the steering mechanism is studied using a numerical computation method. Results show that when the two clearances are equal, the planar movement of the tie rods changes from period-doubling to chaos as the clearances increase. When the two clearances are 0.25 mm and 1.5 mm respectively, the planar movements of the two side tie rods come into chaos, causing the steering stability to deteriorate. Moreover, with the increase of clearances, turning moment fluctuates more intensively and the peak value increases. [ABSTRACT FROM AUTHOR]

RNA silencing is a common mechanism that plays a key role in antiviral defense. To overcome host defense responses, plant viruses encode silencing-suppressor proteins to target one or several key steps in the silencing machinery. Here, we report that the P6 protein encoded by Strawberry vein banding virus (SVBV) is an RNA silencing suppressor through Agrobacterium -mediated co-infiltration assays. SVBV P6 protein can suppress green fluorescent protein ( GFP ) gene silencing induced by single-stranded RNA but not by double-stranded RNA. The P6 protein can also inhibit systemic silencing of GFP through interfering the systemic spread of GFP silencing signal. Subcellular localization study indicated that P6 protein formed irregular bodies and distributed in both cytoplasm and nucleus of Nicotiana benthamiana cells. Furthermore, deletion analysis indicated that a nuclear localization signal (NLS, aa 402–426) in the P6 protein is responsible for the silencing suppression efficiency. In addition, expression of the P6 protein via a Potato virus X (PVX)-based vectors induced more severe mosaic symptoms in N. benthamiana leaves, and transgenic N. benthamiana plants expressing P6 showed obvious vein yellowing as well as severe mosaic symptoms in leaves. Taken together, our results demonstrates that SVBV P6 is a suppressor of RNA silencing, possibly acting at a upstream step for dsRNA generation. [ABSTRACT FROM AUTHOR]

In recent years, an expansion of irrigated agriculture and rapid population growth have threatened the Tarim River basin's natural ecosystems and caused water shortages. Improving the water resources management in the basin requires accurate seasonal precipitation forecasts. Based on previous research, possible predictors of precipitation were selected and either downloaded directly or calculated using NCEP/NCAR Reanalysis 1 or NOAA Extended Reconstructed Sea Surface Temperature (SST) V3b data. Predictors were correlated with precipitation data, provided by the National Climate Centre of the China Meteorological Administration for the period 1961 to 2010 and averaged over the subbasins of the Tarim River. The Spearman rank correlation analyses with lead times of up to six months (or two seasons) revealed significant (at the 1% level) and strong (ρ ≤ −0.6 or ρ ≥ 0.6) correlations of precipitation in all subbasins with the SST and monsoon indices as well as with the Siberian High Intensity (SHI) and the Westerly Circulation Index (WCI). Lastly, we demonstrate the setup of a forecast model based on a multiple linear regression on the example of the Hotan River subbasin. This model predicts precipitation 5 months in advance with reasonable accuracy in two out of three configurations. [ABSTRACT FROM AUTHOR]