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Objectives: The new daily persistent headache (NDPH) is a rare primary headache disorder. However, the underlying mechanisms of NDPH remain incompletely understood. This study aims to apply seed‐based analysis to explore the functional connectivity (FC) of brainstem nuclei in patients with NDPH using resting‐state functional magnetic resonance imaging (MRI). Methods: The FC analysis from the region of interest (ROI) to whole brain voxels was used to investigate 29 patients with NDPH and 37 well‐matched healthy controls (HCs) with 3.0 Tesla MRI. The 76 nuclei in the brainstem atlas were defined as ROIs. Furthermore, we explored the correlations between FC and patients' clinical characteristics and neuropsychological evaluations. Results: Patients with NDPH exhibited reduced FC in multiple brainstem nuclei compared to HCs (including right inferior medullary reticular formation, right mesencephalic reticular formation, bilateral locus coeruleus, bilateral laterodorsal tegmental nucleus‐central gray of the rhombencephalon, median raphe, left medial parabrachial nucleus, periaqueductal gray, and bilateral ventral tegmental area‐parabrachial pigmented nucleus complex) and increased FC in periaqueductal gray. No significant correlations were found between the FC of these brain regions and clinical characteristics or neuropsychological evaluations after Bonferroni correction (p > 0.00016). Conclusions: Our results demonstrated that patients with NDPH have abnormal FC of brainstem nuclei involved in the perception and regulation of pain and emotions. [ABSTRACT FROM AUTHOR]

Aims: Deep brain stimulation (DBS) of the anterior nucleus of the thalamus, is an effective therapy for patients with drug‐resistant epilepsy, yet, its mechanism of action remains elusive. Adenosine kinase (ADK), a key negative regulator of adenosine, is a potential modulator of epileptogenesis. DBS has been shown to increase adenosine levels, which may suppress seizures via A1 receptors (A1Rs). We investigated whether DBS could halt disease progression and the potential involvement of adenosine mechanisms. Methods: Control group, SE (status epilepticus) group, SE‐DBS group, and SE‐sham‐DBS group were included in this study. One week after a pilocarpine‐induced status epilepticus, rats in the SE‐DBS group were treated with DBS for 4 weeks. The rats were monitored by video‐EEG. ADK and A1Rs were tested with histochemistry and western blot, respectively. Results: Compared with the SE group and SE‐sham‐DBS group, DBS could reduce the frequency of spontaneous recurrent seizures (SRS) and the number of interictal epileptic discharges. The DPCPX, an A1R antagonist, reversed the effect of DBS on interictal epileptic discharges. In addition, DBS inhibited the overexpression of ADK and the downregulation of A1Rs. Conclusion: The findings indicate that DBS can reduce SRS in epileptic rats via inhibition of ADK and activation of A1Rs. A1Rs might be a potential target of DBS for the treatment of epilepsy. [ABSTRACT FROM AUTHOR]

Aims: Mesial temporal lobe epilepsy without hippocampal sclerosis (no‐HS MTLE) refers to those MTLE patients who have neither magnetic resonance imaging (MRI) lesions nor definite pathological evidence of hippocampal sclerosis. They usually have resistance to antiepileptic drugs, difficulties in precise seizure location and poor surgical outcomes. Adenosine is a neuroprotective neuromodulator that acts as a seizure terminator in the brain. The role of adenosine in no‐HS MTLE is still unclear. Further research to explore the aetiology and pathogenesis of no‐HS MTLE may help to find new therapeutic targets. Methods: In surgically resected hippocampal specimens, we examined the maladaptive changes of the adenosine system of patients with no‐HS MTLE. In order to better understand the dysregulation of the adenosine pathway in no‐HS MTLE, we developed a rat model based on the induction of focal cortical lesions through a prenatal freeze injury. Results: We first examined the adenosine system in no‐HS MTLE patients who lack hippocampal neuronal loss and found ectopic expression of the astrocytic adenosine metabolising enzyme adenosine kinase (ADK) in hippocampal pyramidal neurons, as well as downregulation of neuronal A1 receptors (A1Rs) in the hippocampus. In the no‐HS MTLE model rats, the transition of ADK from neuronal expression to an adult pattern of glial expression in the hippocampus was significantly delayed. Conclusions: Ectopic expression of neuronal ADK might be a pathological hallmark of no‐HS MTLE. Maladaptive changes in adenosine metabolism might be a novel target for therapeutic intervention in no‐HS MTLE. [ABSTRACT FROM AUTHOR]

BACKGROUND: Clausena lansium (Lour.) Skeels, belonging to the genus Clausena of the family Rutaceae, has a wide range of medical and agricultural activities. Previous studies on agricultural activities have shown that C. lansium extracts and some components have obvious herbicidal activities. In order to study systematically herbicidal activity of this plant, we studied the herbicidal effect of ethyl acetate (EtOAc) extract from the stems and leaves of this plant and further isolated the active compounds. RESULTS: The EtOAc extract inhibited the growth of roots and shoots of Echinochloa crus‐galli (L.) Beauv., and the inhibitory effect of the EtOAc extract on roots were stronger than those on shoots with half maximal inhibitory concentration (IC50) values of 420.45 and 585.05 mg L−1, respectively. Fifteen compounds were subsequently isolated and identified from the stems and leaves of C. lansium, including nine O‐monoterpenoid furanocoumarins and six cinnamamides. Our results showed that most compounds exhibited varying degrees of herbicidal activities to E. crus‐galli. Among them, compounds 3, 8, and 13–15 showed the best inhibitory activities on the growth of E. crus‐galli roots, with inhibition rate values ranging from 70% to 83% at a concentration of 300 mg L−1. Compounds 1 and 2 are two new compounds, and their structures were established as 5‐O‐monoterpenoid furanocoumarin and 8‐O‐monoterpenoid furanocoumarin, and named as claulansicoumarin‐A and ‐B, respectively. CONCLUSION: The EtOAc extract and pure compounds showed noticeable herbicidal activities against E. crus‐galli and indicated a great potential for these natural compounds to be developed as a herbicide. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Conventional switching table‐based direct power control (DPC) usually suffers from higher power ripples due to the heuristic nature of the switching table. This study presents a novel model predictive DPC (MPDPC) strategy for grid‐connected three‐level inverters. In the proposed MPDPC strategy, a new synchronous frame‐based predictive model is first developed and the conjugate of the complex power is then chosen as the control variable to simplify the analysis. Based on the newly developed predictive model, new principles of the voltage vector selection are further derived with the strict analytical proof to match all the control requirements, including the active and reactive power control, neutral point potential balance control, as well as the avoidance of the high voltage jumps. Finally, experimental results are provided to support the theoretical study and confirm the effectiveness of the proposed MPDPC strategy, as well as to demonstrate better performance in both steady‐state and dynamic responses over the conventional DPC. [ABSTRACT FROM AUTHOR]

Enzymatic digestion, the commonly used method of adipose-derived stromal cells isolation, is time consuming and expensive, especially when applied to large volumes of tissue. In the present study, the characteristics of the cells obtained by adipose tissue explant culture were studied. We found that adipose tissue fragments could adhere onto the growth surface of flasks in a very short time after plating and that fibroblast-like cells migrated from the explants and reached confluence. Morphologic analysis and surface markers expression suggested the mesenchymal origin of the cells derived from adipose tissue explants. After in vitro expansion these cells were successfully induced into adipogenic, osteogenic, and chondrogenic lineages, which demonstrated their multipotency. The high growth rate and colony-forming efficiency of explant-derived cells were similar to those of cells obtained by digestion. Furthermore, explant culture gave higher yield of cells than digestion method after primary culture. The experiment of ectopic adipogenesis in nude mice suggested the prospects for tissue engineering of these cells. In conclusion, we obtained multipotent stromal cells from adipose tissue by explant culture, and this method was simple, time saving, and gave a high yield of cells. Therefore, explant culture can be used as an effective way to isolate adipose-derived stromal cells for tissue engineering., (© 2010, Copyright the Authors. Artificial Organs © 2010, International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.)