Publications by authors named "Xiaomin Pang"

18 Publications

  • Page 1 of 1

Aberrant cerebral intrinsic activity and cerebro-cerebellar functional connectivity in right temporal lobe epilepsy: a resting-state functional MRI study.

Neuroreport 2021 Jun 1. Epub 2021 Jun 1.

Department of Neurology, the People's Hospital of Guangxi Zhuang Autonomous Region Department of Neurology, The First Affiliated Hospital of Guangxi Medical University, Nanning, China.

Objective: Numerous neuroimaging studies have demonstrated that functional brain aberrations are associated with cognitive impairments in temporal lobe epilepsy (TLE). Here, we aimed to investigate the neural substrates of attention deficits by combining assessment of regional intrinsic brain activities with large-scale functional connectivity in patients with right TLE (rTLE).

Methods: Thirty-five patients with rTLE and 33 matched healthy controls were recruited. All participants completed the Attention Network Test (ANT) and resting-sate functional MRI (rs-fMRI) scans. The z-standardized fractional amplitude of the low-frequency fluctuation (zfALFF) approach was applied to evaluate the brain's intrinsic activity. The cerebral regions with significant zfALFF values were selected as seeds for subsequent functional connectivity analyses. A correlation analysis was performed between functional activity and clinical variables.

Results: Compared with the healthy control group, the patients showed decreased zfALFF in the right inferior temporal gyrus and bilateral superior parietal gyrus, and the right inferior temporal gyrus exhibited increased functional connectivity with the bilateral cerebellum-6/vermis-6 and decreased functional connectivity with right superior frontal gyrus. The ANT indicated that the rTLE group exhibited attention deficits. Furthermore, a positive correlation was found between the zfALFF value of the left superior parietal gyrus and alerting performance, while a negative correlation between the zfALFF value of the right superior parietal gyrus and disease duration.

Conclusion: This study demonstrated aberrant intrinsic cerebral activity and functional connectivity in the whole brain network, which may act as responsible and compensatory factors in attention deficits, especially further profoundly illuminated the compensatory role of cerebellum in patients with rTLE.
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http://dx.doi.org/10.1097/WNR.0000000000001681DOI Listing
June 2021

Altered interhemispheric functional homotopy and connectivity in temporal lobe epilepsy based on fMRI and multivariate pattern analysis.

Neuroradiology 2021 May 3. Epub 2021 May 3.

Department of Neurology, the First Affiliated Hospital of Guangxi Medical University, Nanning, China.

Purpose: This study aimed to investigate how the functional homotopy and further functional connectivity (FC) of whole brain changed in temporal lobe epilepsy (TLE). We also evaluated which brain regions played a decisive role in classification by using functional magnetic resonance imaging (fMRI).

Methods: Patients with TLE and matched healthy controls were included to collect the fMRI data and perform the voxel-mirrored homotopic connectivity (VMHC) and FC analyses. The correlation between the changed functional homotopy and neuropsychology tests was examined. Based on VMHC, the weight of each region in the classification was obtained using multivariate pattern analysis (MVPA).

Results: The patients exhibited decreased functional coordination in the bilateral inferior temporal gyrus (ITG) and increased functional homotopy in the bilateral lingual gyrus compared with the control group in the VMHC analysis. Compared with healthy controls, the Montreal Cognitive Assessment score was lower, and the scores of Hamilton Anxiety (HAMA) and Hamilton Depression Scales were higher. The score of the HAMA Scale was positively correlated with the altered bilateral ITG. The FC analysis revealed increased connections between the right lingual gyrus and the left superior temporal gyrus/left insula. The MVPA showed that the accuracy, sensitivity, and specificity of classification were 68.49, 66.67 and 70.27%, respectively, and it confirmed that the temporal lobe, cerebellum, and parietal lobe provided significant contributions.

Conclusion: These findings demonstrated that the VMHC and FC changed in TLE, and the alterations were correlated with the anxiety state. The MVPA indicated that the abnormal VMHC was a crucial fMRI feature.
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http://dx.doi.org/10.1007/s00234-021-02706-xDOI Listing
May 2021

The Insula Is a Hub for Functional Brain Network in Patients With Anti--Methyl-D-Aspartate Receptor Encephalitis.

Front Neurosci 2021 15;15:642390. Epub 2021 Mar 15.

Department of Neurology, The First Affiliated Hospital of Guangxi Medical University, Nanning, China.

Background: In recent years, imaging technologies have been rapidly evolving, with an emphasis on the characterization of brain structure changes and functional imaging in patients with autoimmune encephalitis. However, the neural basis of anti--methyl-D-aspartate receptor (NMDAR) encephalitis and its linked cognitive decline is unclear. Our research aimed to assess changes in the functional brain network in patients with anti-NMDAR encephalitis and whether these changes lead to cognitive impairment.

Methods: Twenty-one anti-NMDAR encephalitis patients and 22 age-, gender-, and education status-matched healthy controls were assessed using resting functional magnetic resonance imaging (fMRI) scanning and neuropsychological tests, including the Hamilton Depression Scale (HAMD), the Montreal Cognitive Assessment (MoCA), and the Hamilton Anxiety Scale (HAMA). A functional brain network was constructed using fMRI, and the topology of the network parameters was analyzed using graph theory. Next, we extracted the aberrant topological parameters of the functional network as seeds and compared causal connectivity with the whole brain. Lastly, we explored the correlation of aberrant topological structures with deficits in cognitive performance.

Results: Relative to healthy controls, anti-NMDAR encephalitis patients exhibited decreased MoCA scores and increased HAMA and HAMD scores ( < 0.05). The nodal clustering coefficient and nodal local efficiency of the left insula (Insula_L) were significantly decreased in anti-NMDAR encephalitis patients ( < 0.05 following Bonferroni correction). Moreover, anti-NMDAR encephalitis patients showed a weakened causal connectivity from the left insula to the left inferior parietal lobe (Parietal_Inf_L) compared to healthy controls. Conversely, the left superior parietal lobe (Parietal_sup_L) exhibited an enhanced causal connectivity to the left insula in anti-NMDAR encephalitis patients compared to controls. Unexpectedly, these alterations were not correlated with any neuropsychological test scores.

Conclusion: This research describes topological abnormalities in the functional brain network in anti-NMDAR encephalitis. These results will be conducive to understand the structure and function of the brain network of patients with anti-NMDAR encephalitis and further explore the neuropathophysiological mechanisms.
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http://dx.doi.org/10.3389/fnins.2021.642390DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8005702PMC
March 2021

Fasciculation score: a sensitive biomarker in amyotrophic lateral sclerosis.

Neurol Sci 2021 Mar 11. Epub 2021 Mar 11.

Department of Neurology, First Hospital, Shanxi Medical University, No.85, Jiefang South Street, Taiyuan, 030000, People's Republic of China.

Objective: The aim of our study was to elucidate the characteristic of fasciculation distributions in amyotrophic lateral sclerosis (ALS) using a fasciculation score (FS) of muscle ultrasound (MUS) and to compare the diagnostic values of three MUS fasciculation parameters in patients.

Methods: Thirty ALS patients, 16 ALS mimics, and 10 healthy subjects were involved. MUS of unilateral 10 muscles in each patient and needle electromyography (EMG) of total 204 muscles were performed to detect fasciculations and spontaneous activity respectively in ALS. Control groups underwent only MUS. Fasciculation was graded semiquantitatively with FS.

Results: Three hundred fifty muscles in ALS and 260 in controls were examined. The fasciculation detection rates, total FS, the number of muscles with fasciculation, and the total number of fasciculations in ALS were all significantly higher than those of controls (P < 0.001). ALS patients exhibited a multifocal continuous pattern of fasciculation in limbs, whereas there were few fasciculations in controls. Compared with other parameters, total FS had the largest area under the curve (AUC) (AUC = 0.899, P < 0.001) in ALS diagnosis. The detection rates of lower motor neuron (LMN) acute lesions by MUS (70.6%) and EMG (72.1%) were nearly the same, and a positive correlation between the FS and spontaneous activity grades (P < 0.001, r = 0.359) was proved.

Conclusions: ALS patients exhibited the multifocal continuous pattern of fasciculation in limbs. FS showed high sensitivity and specificity in differentiating ALS from non-ALS patients, and the optimal cut-off value was determined as 4. The combination of MUS and EMG can provide additional information about specific muscles.
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http://dx.doi.org/10.1007/s10072-021-05166-6DOI Listing
March 2021

A novel Q93H missense mutation in DCTN1 caused distal hereditary motor neuropathy type 7B and Perry syndrome from a Chinese family.

Neurol Sci 2021 Jan 14. Epub 2021 Jan 14.

Department of Neurology, First Hospital, Shanxi Medical University, No.85, Jiefang South Street, Taiyuan, China.

The Dynactin 1 (DCTN1) encodes the p150 subunit of dynactin, which engages retrograde axonal transport. Missense mutations in DCTN1 have been linked to a series of neurodegenerative diseases, including distal hereditary motor neuropathies (dHMN) and Perry syndrome. A few pathogenic DCTN1 mutations related with Perry syndrome have been described within, or adjacent to, the highly conserved N-terminal cytoskeleton-associated protein, glycine-rich (CAP-Gly) domain. But to our best knowledge, only the pathogenic G59S mutation in DCTN1 has been reported in dHMN7B families. Herein, we provided a novel heterozygous mutation in DCTN1 which caused both dHMN7B and Perry syndrome from a Chinese family. Whole exome sequencing (WES) was performed to identify the disease-associated genes. Single nucleotide variants (SNVs) and small insertions/deletions (INDELs) were further predicted with Mutation Taster, Polymorphism Phenotyping v2 (PolyPhen-2), and Sorting Intolerant From Tolerant (SIFT) and compared to the Single Nucleotide Polymorphism Database(dbSNP), Exome Aggregation Consortium (ExAC), and the 1000 Genomes Project. Furthermore, a novel missense mutation c.279G>C (Q93H) in DCTN1 was identified as the candidate loci. The mutation was confirmed with Sanger sequencing in the family members and cosegregated with various phenotypes. In silico analysis and molecular structural modeling, the mutation not only caused the loss of a hydrogen bond within the p150 protein but also affected the formation of hydrogen bonds between p150 and EB. Therefore, the new Q93H mutation in DCTN1 caused both familial dHMN7B and Perry syndrome. Our findings could expand the clinical and pathogenic spectrum and strengthen the clinical diagnostic role of the DCTN1 gene.
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http://dx.doi.org/10.1007/s10072-020-04962-wDOI Listing
January 2021

Whole-exome sequencing identifies a heterozygous mutation in SLC12A6 associated with hereditary sensory and motor neuropathy.

Neuromuscul Disord 2021 02 18;31(2):149-157. Epub 2020 Nov 18.

Department of Neurology, First Hospital, Shanxi Medical University, Taiyuan 030000, PR China. Electronic address:

Charcot-Marie-Tooth disease (CMT) represents a phenotypically and genetically heterogeneous disorder of the peripheral nervous system. Biallelic variants in SLC12A6 have been reported as the cause of autosomal-recessive (AR) hereditary motor and sensory neuropathy with agenesis of the corpus callosum (HMSN/ACC). Here we identified an autosomal-dominant (AD) heterozygous mutation in SLC12A6 in a Chinese patient with intermediate CMT. The patient presented with slowly progressive distal muscle weakness and atrophy. Electrophysiological examination showed a mixed axonal/demyelinating neuropathy. Cognition and brain MRI were normal. A single heterozygous missense mutation c.620G>A (p.R207H) in exon 5 of SLC12A6 was identified as the likely pathogenic mutation by whole-exome sequencing consistent with two previously published cases. It affects evolutionarily highly conserved amino acid residue and is predicted to be deleterious by using in silico tools. Modelling of the mutant KCC3 cotransporter showed altered formation of hydrogen bonds and weakened interaction force between the mutated site and its surrounding amino acid residues. Our findings expand the genotypic and phenotypic spectrum associated with SLC12A6 mutations from AR-HMSN/ACC to AD-CMT. The differences in the inheritance pattern might be associated with a dominant-negative pathomechanism.
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http://dx.doi.org/10.1016/j.nmd.2020.11.002DOI Listing
February 2021

Comparison of topological properties of functional brain networks with graph theory in temporal lobe epilepsy with different duration of disease.

Ann Transl Med 2020 Nov;8(22):1503

Department of Neurology, the First Affiliated Hospital of Guangxi Medical University, Nanning, China.

Background: Our study was performed to measure the alterations in topological properties of the functional brain network of temporal lobe epilepsy (TLE) at different durations, exploring the potential progression and neuropathophysiological mechanisms of TLE.

Methods: Fifty-eight subjects, including 17 TLE patients with a disease duration of ≤5 years (TLE-SD), 20 TLE patients with a disease duration of >5 years (TLE-LD), and 21 healthy controls firstly underwent the Attention Network Test (ANT) to assess the alertness function and received the resting-state functional magnetic resonance imaging (rs-fMRI). Next, a functional brain network was set up, and then the related graph of theoretical network analysis was conducted. Finally, the correlation between network property and the neuropsychological score was analyzed.

Results: The global and local efficiencies of functional brain networks in TLE-SD patients significantly decreased and tended toward random alterations. Also, the degree centrality (DC) and nodal efficiency (Ne) in right medial pre-frontal thalamus (mPFtha) and right rostral temporal thalamus (rTtha) of TLE-SD patients significantly reduced. Further analysis showed that alertness was positively associated with the characteristic path length but negatively related to the global and local efficiencies in TLE-SD patients; alertness was negatively related to the Ne of mPFtha in TLE-LD patients.

Conclusions: Our study showed that the functional brain network of TLE patients might undergo compensatory reorganization as the disease progresses, which provides useful insights into the progression and mechanism of TLE.
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http://dx.doi.org/10.21037/atm-20-6823DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7729351PMC
November 2020

Disrupted alertness and related functional connectivity in patients with focal impaired awareness seizures in temporal lobe epilepsy.

Epilepsy Behav 2020 11 25;112:107369. Epub 2020 Aug 25.

Department of Neurology, the First Affiliated Hospital of Guangxi Medical University, Nanning 530021, China. Electronic address:

Objective: Focal impaired awareness seizures are common in temporal lobe epilepsy (TLE). The cognitive impairment associated with this type of seizure is unclear. Alertness is a fundamental aspect of cognition. The locus coeruleus (LC) is closely related to alertness. We aimed to assess the impairment in alertness and LC-related alertness network in patients with focal impaired awareness seizures.

Methods: Patients with unilateral TLE were grouped into the only focal impaired awareness seizure group (focal group, n = 19) and the focal impaired awareness seizure with focal to bilateral tonic-clonic seizure (FBTCS) group (FBTCS group, n = 19) and compared with matched healthy controls (HC, n = 19). Alertness was assessed with the attention network test. Functional magnetic resonance imaging (fMRI) was used to construct an alertness-related LC-based functional connectivity (FC) network.

Results: The focal group exhibited impaired tonic and phasic alertness and exhibited a decreased trend of LC-based FC to the left superior frontal gyrus (SFG). The FBTCS group exhibited impaired tonic alertness, phasic alertness, and alertness efficiency. No significant difference or trend in LC-based FC was found in the FBTCS group.

Significance: This study reveals disrupted alertness and alertness-related LC-based FC in patients with focal impaired awareness seizures. Our results further demonstrate that the patterns of impaired alertness and of changed LC-based FC were not significantly different between focal impaired awareness seizures and FBTCS.
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http://dx.doi.org/10.1016/j.yebeh.2020.107369DOI Listing
November 2020

Longitudinal assessment of resting-state fMRI in temporal lobe epilepsy: A two-year follow-up study.

Epilepsy Behav 2020 02 31;103(Pt A):106858. Epub 2019 Dec 31.

Department of Neurology, The First Affiliated Hospital of Guangxi Medical University, Nanning, China. Electronic address:

In this study, we aimed to detect longitudinal alterations in local spontaneous brain activity and functional connectivity (FC) of the default mode network (DMN) in patients with temporal lobe epilepsy (TLE) over a two-year follow-up. We used amplitude of low-frequency fluctuation (ALFF) analysis and independent component analysis (ICA) to explore differences in local spontaneous brain activity and FC strength. In total, 33 participants (16 patients with TLE and 17 age- and gender-matched healthy controls (HCs)) were recruited in this study. All participants performed the Attention Network Test (ANT) for evaluation of the executive control function. Compared with healthy patients at baseline, patients with TLE at follow-up exhibited increased ALFF values in the left medial frontal gyrus, as well as reduced FC values in the left inferior parietal gyrus (IPG) within the DMN. Patients with TLE revealed executive dysfunction, but no progressive deterioration was observed during follow-up. This study revealed the abnormal distribution of ALFF values and Rs-FC changes over a two-year follow-up period in TLE, both of which demonstrated different reorganization trajectories and loss of efficiency.
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http://dx.doi.org/10.1016/j.yebeh.2019.106858DOI Listing
February 2020

Disruption and lateralization of cerebellar-cerebral functional networks in right temporal lobe epilepsy: A resting-state fMRI study.

Epilepsy Behav 2019 07 15;96:80-86. Epub 2019 May 15.

Department of Neurology, The First Affiliated Hospital of Guangxi Medical University, Nanning, China. Electronic address:

Numerous studies have highlighted important roles for the cerebellum in cognition and movement, based on numerous fiber connections between the cerebrum and cerebellum. Abnormal cerebellar activity caused by epileptic discharges has been reported in previous studies, but researchers have not clearly determined whether aberrant cerebellar activity contributes to the disruption of the cerebellar-cerebral networks in right temporal lobe epilepsy (rTLE). Here, thirty patients with rTLE and 30 age- and sex-matched healthy controls (HCs) were recruited. All participants underwent the Attention Network Test (ANT) and resting-state functional magnetic resonance imaging (rs-fMRI) scanning. Cerebellar functional networks were extracted and analyzed by defining seeds in the cerebellum. A correlation analysis was performed between attentional performance and voxels that showed differences in functional connectivity (FC) in patients compared with HCs. Relative to HCs, patients exhibited significantly decreased FC in the dentate nucleus (DN) network (right DN with the left postcentral gyrus, left precentral gyrus, left cuneus, and left calcarine gyrus) and motor network (right cerebellar lobule V with the right putamen) and increased FC in the executive control network (right cerebellar crus I with the right inferior parietal lobule). Alerting, orienting, and executive control performances were impaired in patients with rTLE. Furthermore, the executive control effect was significantly correlated with aberrant FC strength between the right DN and the left precentral/postcentral gyrus. Our findings highlight that the disrupted cerebellar-cerebral functional network ipsilateral to the epileptogenic focus causes both impairments in and compensatory effects on attentional deficits in patients with rTLE. These findings contribute to our understanding of the cerebellar damage caused by epileptic discharges and the corresponding effect on attentional performance.
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http://dx.doi.org/10.1016/j.yebeh.2019.03.020DOI Listing
July 2019

Diversiform Etiologies for Post-stroke Depression.

Front Psychiatry 2018 23;9:761. Epub 2019 Jan 23.

Department of Neurology and Neuroscience Center, The First Bethune Hospital of Jilin University, Changchun, China.

After the onset of stroke, many patients suffer from emotional behavior changes. Approximately, one-third of stroke survivors are affected by post-stroke depression (PSD), making it a serious social and public health problem. Post-stroke depression (PSD) has an important impact on the course, recovery, and prognosis of stroke. The pathogenesis of PSD is very complex, involving many factors such as biological mechanism and social psychological mechanisms. This article provides a brief review of the hot issues related to etiologies of PSD.
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http://dx.doi.org/10.3389/fpsyt.2018.00761DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6351464PMC
January 2019

In situ synthesis of a monolithic material with multi-sized pores and its chromatographic properties for the separation of intact proteins from human plasma.

Talanta 2019 Mar 18;194:406-414. Epub 2018 Oct 18.

College of Pharmaceutical Sciences, Hebei University, Baoding 071002, China.

The fabrication of a monolithic allyl phenoxyacetate-based material was proposed via the in situ radical polymerization using ethylene dimethacrylate as the crosslinker and 2,2'-azobisisobutyronitrile as the initiator within a stainless steel column (50 mm × 4.6 mm i.d.). The effects of the porogen composition, the crosslinker amount and the monomer type on the resulting monoliths were investigated. The morphology of the monoliths was characterized using scanning electron microscopy and a nitrogen adsorption-desorption instrument, and the pore structure was characterized using mercury intrusion porosimetry. The results indicate that the optimized monolith has a micro-, meso- and macro- multi-sized pore structure with a high specific surface area of 260.66 m g. The resulting monoliths were used as stationary phases for the separation of proteins from bio-samples, including a mixture of six standard proteins, chicken egg whites, snailase and human plasma, using high-performance liquid chromatography. Compared to optimized glycidyl methacrylate-based and styrene-based monolithic columns, the allyl phenoxyacetate-based monolithic column exhibited improved selectivity in the separation of proteins. Furthermore, the present method avoids the masking of highly abundant proteins, such as human serum albumin, immunoglobulin G and human fibrinogen, in the detection of middle- or low-abundance proteins in human plasma. The protein identification results obtained from liquid chromatography/mass spectrometry indicate that the present method is an outstanding method for efficient fractionation of human plasma, which will be especially useful in future plasma proteomics research.
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http://dx.doi.org/10.1016/j.talanta.2018.10.054DOI Listing
March 2019

A novel poly (NMA-co-DEA-co-EDMA) monolithic column as a sorbent for online solid-phase extraction and its application in the determination of β-sitosterol in plant oil samples.

Food Chem 2019 Apr 22;278:594-600. Epub 2018 Nov 22.

Key Laboratory of Pharmaceutical Quality Control of Hebei Province, College of Pharmaceutical Sciences, Hebei University, Baoding 071002, China; Key Laboratory of Medicinal Chemistry and Molecular Diagnosis, Ministry of Education, Baoding 071002, China. Electronic address:

A novel monolithic column was prepared by in-situ free radical polymerization using N-methylolacrylamide (NMA) and N,N-diethylacrylamide (DEA) as co-monomers. The monolith was characterized by scanning electron microscopy (SEM) and its nitrogen adsorption-desorption isotherm, and it was used as a solid phase extraction (SPE) absorbent for the online enrichment of β-sitosterol by high performance liquid chromatography. The optimized method had good linearity, and the linear regression coefficient was 0.998. The limit of detection (LOD) and the limit of quantification (LOQ) were 0.006 mg/mL and 0.02 mg/mL, respectively. The interday and intraday accuracies were less than 7.28%. The spiked recoveries of β-sitosterol in the six plant oil were 90.96-103.56%. The maximum amount of β-sitosterol adsorbed on the monolithic column was 12.69 mg/g, and the enrichment factor of β-sitosterol was 78. The results showed that the monolith could be used as an online SPE absorbent for the determination of β-sitosterol in plant oil samples.
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http://dx.doi.org/10.1016/j.foodchem.2018.11.104DOI Listing
April 2019

A case of concurrent diurnal and nocturnal paroxysmal dystonia.

Neurol Sci 2018 Dec 13;39(12):2217-2220. Epub 2018 Aug 13.

Department of Neurology, The First Affiliated Hospital of Guangxi Medical University, No 6, Shuangyong Road, Nanning, Guangxi, China.

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http://dx.doi.org/10.1007/s10072-018-3532-xDOI Listing
December 2018

Separation of proteins from complex bio-matrix samples using a double-functionalized polymer monolithic column.

Analyst 2017 Dec;143(1):280-288

College of Pharmaceutical Sciences, Hebei University, Baoding, 071002, China.

A double-functionalized polymer monolithic column was fabricated within the confines of a stainless-steel column (50 mm × 4.6 mm i.d.) via a facile method using iron porphyrin, ionic liquid (1-allyl-3-methylimidazolium chloride) and 1,10-decanediol dimethacrylate as tri-monomers; ethylene dimethacrylate as a crosslinker; polyethylene glycol 400 and N,N-dimethylformamide as co-porogens; benzoyl peroxide and N,N-dimethyl aniline as the redox initiation system. Results obtained from scanning electron microscopy, nitrogen adsorption-desorption, and mercury intrusion porosimetry confirmed the uniform pore structure and the pore size distribution of macro-pores. The home-made monolith was further characterized by elemental analysis to investigate the elemental composition of Fe supplied by iron porphyrin, confirming the synthetic process. The resulting optimized monolithic column was used as the stationary phase in high performance liquid chromatography for separating proteins, such as mixture of standard proteins, egg white, and human plasma, exhibiting good selectivity and high performance. It is worth noting that the home-made double-functionalized polymer monolithic column shows excellent selectivity for fractionation separation of human plasma proteins, and it is a promising separation tool for complex bio-samples in proteomic research.
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http://dx.doi.org/10.1039/c7an01491kDOI Listing
December 2017

Fractionation separation of human plasma proteins using HPLC with a homemade iron porphyrin based monolithic column.

J Chromatogr B Analyt Technol Biomed Life Sci 2017 Nov 4;1068-1069:358-364. Epub 2017 Nov 4.

Key Laboratory of Medicinal Chemistry and Molecular Diagnosis, Ministry of Education, Hebei University, Baoding, 071002, China.

In this work a polymer monolithic column was fabricated within the confines of a stainless steel column (50×4.6mm i.d.) via radical polymerization by using iron porphyrin and butyl methacrylate as co-monomers, ethylene glycol dimethacrylate as crosslinking agent, ethylene glycol, isopropyl alcohol and N, N-dimethylformamide as tri-porogens, benzoyl peroxide and N,N-dimethylaniline as initiators. The resulting monolithic column was characterized by elemental analysis, scanning electron microscopy, nitrogen adsorption BET surface area, and mercury intrusion porosimetry, respectively. Results showed that the homemade monolith occupied relatively uniform pore structure, low back pressure, and enhanced selectivity for proteins in complex bio-samples. The present work described a simple and efficient method for "fractionation separation" of human plasma proteins, and it is a promising separation method for complex bio-samples in proteomic research.
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http://dx.doi.org/10.1016/j.jchromb.2017.11.003DOI Listing
November 2017

MicroRNA-146a down-regulation correlates with neuroprotection and targets pro-apoptotic genes in cerebral ischemic injury in vitro.

Brain Res 2016 10 20;1648(Pt A):136-143. Epub 2016 Jul 20.

Department of Neurology, The First Affiliated Hospital, Guangxi Medical University, Nanning 530021, China. Electronic address:

MicroRNAs (miRNAs) are short, non-coding RNAs that negatively regulate target gene expression, and play an important role in cerebral ischemic injury. MiR-146a has been reported to be highly related to cell invasion, metastasis, immunity, inflammation and apoptosis. Previous studies have indicated that miR-146a can either inhibit or promote apoptosis through different pathophysiological processes. In our previous study, miR-146a in the blood was down-regulated during acute ischemic stroke. However, the connection between miR-146a and acute cerebral ischemic injury and the mechanism underlying the connection remain unclear. Here, we aimed to investigate the role of miR-146a and its possible target genes in human SK-N-SH cells subjected to 16h of oxygen-glucose deprivation and 12h of reperfusion (OGD/R) injury. Cells were transfected with miR-146a mimic or inhibitor to alter the expression of miR-146a. MiR-146a in the SK-N-SH cells was down-regulated after OGD/R injury. Moreover, bioinformatics analysis and dual luciferase assays demonstrated that miR-146a directly recognized the 3'-UTR of the pro-apoptotic genes, Caspase7 and Bcl-2-associated transcription factor 1 (Bclaf1). Furthermore, miR-146a over-expression effectively decreased the mRNA and protein expression of Caspase7 and Bclaf1, and aggravated OGD/R-induced cell apoptosis; in contrast, miR-146a down-regulation was neuroprotective. In conclusion, our study revealed that miR-146a contributes to OGD/R injury in vitro, while negatively regulating the pro-apoptotic genes, Caspase7 and Bclaf1. This special mechanism provides new insight into miRNA regulatory networks. In addition, miR-146a may offer a potential therapeutic approach to cerebral ischemic injury.
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http://dx.doi.org/10.1016/j.brainres.2016.07.034DOI Listing
October 2016

[Separation of 1-phenyl-3-methyl-5-pyrazolone derivatives of traditional Chinese medicine oligosaccharides by capillary zone electrophoresis].

Se Pu 2011 Mar;29(3):254-8

School of Pharmacy, Hebei University, Baoding 071002, China.

A simple and practical capillary zone electrophoretic (CZE) method has been developed for the separation of traditional Chinese medicine oligosaccharides according to their relative molecular masses (M(r)). To optimize the conditions of the method, the concentration and pH value of the running buffer, and the applied voltage were evaluated. The optimized conditions were as follows: 1-phenyl-3-methyl-5-pyrazolone (PMP) derivatives of the oligosaccharides were separated with 50 mmol/L phosphate buffer (pH 2.5) as running buffer and the voltage was 15 kV. The detection was performed with an ultraviolet detector at 245 nm. An uncoated fused-silica capillary of 50 microm i. d. and 38/48 cm length (effective length/total length) was employed, and a hydrodynamic pressure injection (10 cm x 2 s) was applied. In order to examine the practicability of the method for the analysis of actual traditional Chinese medicine oligosaccharide samples, a complex sample consisting of some usual monosaccharides and oligosaccharides degraded from beta-cyclodextrin was separated under the electrophoretic conditions. And then, the method was applied to the analysis of the controlled degradation products of Indigowoad Root polysaccharide. The results indicated that the oligosaccharide sample could fully be separated from low to high M(r). This method is efficient and practical. In addition, the separation hypothesis of PMP derivatives of monosaccharides and oligosaccharides in pH 2.5 running buffer is also discussed, which would be helpful for us to understand the unusual migration of the PMP derivatives of rhamnose and mannose.
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http://dx.doi.org/10.3724/sp.j.1123.2011.00254DOI Listing
March 2011