Efficient removal of allicin from the stalk of Allium fistulosum for dietary fiber production.

The stalk of Allium fistulosum contains dietary fibers with complicated monosaccharide composition and glycosidic bond linkages, which renders it a better dietary fiber supplement. However, the unfavorable odor, majorly contributed by allicin, limits its applications. Although many physical and chemical methods have been developed to remove allicin, there is currently no comparison between their efficiencies. Here, we comprehensively compare all these methods of eliminating allicin in the Allium stalk by starting with optimization of the allicin extraction method. Results indicate that incubation of the chopped Allium stalk with water for 20 min and extraction with 75% ethanol reached a maximal extraction yield. Different methods of allicin elimination are examined, and physical removal of allicin by blanching at 100 °C reaches a maximal clearance rate of 73.3%, rendering it the most efficient and effective method eliminating allicin from the stalk of Allium fistulosum for the preparation of a totally green dietary fiber.

AepG is a glucuronosyltransferase involved in acidic exopolysaccharide synthesis and contributes to environmental adaptation of Haloarcula hispanica.

The attachment of a sugar to a hydrophobic lipid carrier is the first step in the biosynthesis of many glycoconjugates. In the halophilic archaeon Haloarcula hispanica, HAH_1206, renamed AepG, is a predicted glycosyltransferase belonging to the CAZy Group 2 family that shares a conserved amino acid sequence with dolichol phosphate mannose synthases. In this study, the function of AepG was investigated by genetic and biochemical approaches. We found that aepG deletion led to the disappearance of dolichol phosphate-glucuronic acid. Our biochemical assays revealed that recombinant cellulose-binding, domain-tagged AepG could catalyze the formation of dolichol phosphate-glucuronic acid in time- and dose-dependent manners. Based on the in vivo and in vitro analyses, AepG was confirmed to be a dolichol phosphate glucuronosyltransferase involved in the synthesis of the acidic exopolysaccharide produced by H. hispanica. Furthermore, lack of aepG resulted in hindered growth and cell aggregation in high salt medium, indicating that AepG is vital for the adaptation of H. hispanica to a high salt environment. In conclusion, AepG is the first dolichol phosphate glucuronosyltransferase identified in any of the three domains of life and, moreover, offers a starting point for further investigation into the diverse pathways used for extracellular polysaccharide biosynthesis in archaea.

Flexor carpi radialis H-reflex in different body positions in patients with post-stroke.

Background: Spinal stretch reflex (SSR) hyperexcitability reflected by the H-reflex has been reported in more strongly affected extremities after stroke. The H-reflex in the lower extremities is modulated by body position normally and alternatively modulated post-stroke. Objective: This study aimed to preliminarily explore how upper extremity (UE) H-reflexes are modulated by body position after stroke, which remains unknown. Materials and methods: Three patients after stroke with hemiparesis/hemiplegia were included. Bilateral flexor carpi radialis (FCR) H-reflexes were examined in the supine position while standing. Other clinical evaluations include the modified Ashworth scale (MAS) and postural stability measurement. Results: The three cases herein showed that (1) SSR excitability was higher in more strongly affected UEs than less-affected UEs, (2) down-modulation of SSR excitability occurred in less-affected UEs in static standing compared with the supine position, but modulation of SSR excitability in more-affected UEs varied, and (3) bilateral UE SSR excitability in case 3 was down-modulated the most. Moreover, case 3 showed no difference in muscle tone of the more affected UE between supine and standing positions, and case 3 showed the best postural stability. Conclusion: Spinal stretch reflex hyperexcitability in strongly affected UEs could commonly occur in different phases of recovery after stroke. Down-modulation of SSR excitability could occur in less-affected UEs in the standing position compared with the supine position, while modulation of SSR excitability might be altered in strongly affected UEs and vary in different phases of recovery. There could be some correlation between postural control and UE SSR hyperexcitability. The H-reflex may help to offer a new perspective on rehabilitation evaluation and interventions to promote UE motor control after stroke.

Application of tDCS in children with cerebral palsy: A mini review.

Cerebral palsy (CP) refers to a group of diseases characterized by persistent central dyskinesia, postural development disorder and activity limitation syndromes caused by nonprogressive brain injury in the developing fetus or infant, which is often accompanied by sensory, cognitive and attention disorders. The routine rehabilitation methods for children with CP mainly include physical therapy, occupational therapy, speech therapy and other methods. In recent years, noninvasive brain stimulation (NIBS), as a relatively new intervention method, has been widely used because of its potential to regulate cortical excitability and plasticity. Transcranial direct current stimulation (tDCS) is an NIBS technique that is easier and more convenient to perform. It does not require patients to remain stationary for a long time or have a significant impact on treatment results due to children's frequent activities. Compared with other NIBS techniques, tDCS has greater flexibility and no strict restrictions on patients' activities; it also helps the therapist conduct occupational therapy or speech therapy while a child receives tDCS, which markedly reduces the treatment time and avoids burnout due to a long treatment duration. Thus, tDCS is a better and more convenient intervention for CP children and warrants further exploration. Accordingly, this article reviews tDCS application in children with CP and discusses tDCS application prospects for such children to promote its expansion in clinical practice.

Cyclic stretch-induced the cytoskeleton rearrangement and gene expression of cytoskeletal regulators in human periodontal ligament cells.

OBJECTIVE: This study aimed to explore the mechanism of the stretch-induced cell realignment and cytoskeletal rearrangement by identifying several mechanoresponsive genes related to cytoskeletal regulators in human PDL cells. MATERIAL AND METHODS: After the cells were stretched by 1, 10 and 20% strains for 0.5, 1, 2, 4, 6, 12 or 24 h, the changes of the morphology and content of microfilaments were recorded and calculated. Meanwhile, the expression of 84 key genes encoding cytoskeletal regulators after 6 and 24 h stretches with 20% strain was detected by using real-time PCR array. Western blot was applied to identify the protein expression level of several cytoskeletal regulators encoded by these differentially expressed genes. RESULTS: The confocal fluorescent staining results confirmed that stretch-induced realignment of cells and rearrangement of microfilaments. Among the 84 genes screened, one gene was up-regulated while two genes were down-regulated after 6 h stretch. Meanwhile, three genes were up-regulated while two genes were down-regulated after 24 h stretch. These genes displaying differential expression included genes regulating polymerization/depolymerization of microfilaments (CDC42EP2, FNBP1L, NCK2, PIKFYVE, WASL), polymerization/depolymerization of microtubules (STMN1), interacting between microfilaments and microtubules (MACF1), as well as a phosphatase (PPP1R12B). Among the proteins encoded by these genes, the protein expression level of Cdc42 effector protein-2 (encoded by CDC42EP2) and Stathmin-1 (encoded by STMN1) was down-regulated, while the protein expression level of N-WASP (encoded by WASL) was up-regulated. CONCLUSION: The present study confirmed the cyclic stretch-induced cellular realignment and rearrangement of microfilaments in the human PDL cells and indicated several force-sensitive genes with regard to cytoskeletal regulators.

Size-tunable copper nanocluster aggregates and their application in hydrogen sulfide sensing on paper-based devices.

Polystyrene sulfonate (PSS), a strong polyelectrolyte, was used to prepare red photoluminescent PSS-penicillamine (PA) copper (Cu) nanoclusters (NC) aggregates, which displayed high selectivity and sensitivity to the detection of hydrogen sulfide (H2S). The size of the PSS-PA-Cu NC aggregates could be readily controlled from 5.5 µm to 173 nm using different concentrations of PSS, which enabled better dispersity and higher sensitivity towards H2S. PSS-PA-Cu NC aggregates provided rapid H2S detection by using the strong Cu-S interaction to quench NC photoluminescence as a sensing mechanism. As a result, a detection limit of 650 nM, which is lower than the maximum level permitted in drinking water by the World Health Organization, was achieved for the analysis of H2S in spring-water samples. Moreover, highly dispersed PSS-PA-Cu NC aggregates could be incorporated into a plate-format paper-based analytical device which enables ultra-low sample volumes (5 µL) and feature shorter analysis times (30 min) compared to conventional solution-based methods. The advantages of low reagent consumption, rapid result readout, limited equipment, and long-term storage make this platform sensitive and simple enough to use without specialized training in resource constrained settings.

[Cylic stretching force-induced late apoptosis in human periodontal ligament cells].

PURPOSE: To investigate the effect of stretching force on late apoptosis of human periodontal ligament cells. METHODS: HPDLCs were cultured in vitro, and cells were stretched by dynamic mechanical strain 1%, 10% and 20% for 6, 12, 24 and 48 h. Then late apoptosis were detected through TUNEL method binding by flow cytometry and confocal laser scanning microscopy. The data was analyzed with SPSS 11.0 software package. RESULTS: HPDCLs inclined parallel to each other and aligned their long axis perpendicular to the stretching force vector. The number of apoptotic cells increased significantly in a time-and force-dependent manner in response to stretching strain within 24 h. CONCLUSIONS: It is found that stretching force can induce apoptosis in HPDLC and show time- and stress-dependent manner with a tendency of increase in 24 h.

Cyclic stretch induced gene expression of extracellular matrix and adhesion molecules in human periodontal ligament cells.

OBJECTIVE: Periodontal ligament (PDL) cells play an important role in maintaining periodontal homeostasis upon force loading caused by mastication or orthodontic force. Previous studies revealed stretch-induced realignment of human PDL cells, but the mechanism for this phenomenon still remains unclear. As extracellular matrix (ECM) and adhesion molecules play critical roles in cell migration and alignment, this study aimed to identify mechanoresponsive genes related to ECM and adhesion in human PDL cells. DESIGN: Human PDL cells were exposed to 10% stretch strain for 6 or 24 h, and the expression of 84 genes related to ECM and adhesion were analyzed with real-time PCR array. The protein expression of integrin α5 was examined by Western blot and flow cytometric analysis. RESULTS: Among the genes screened, 6 were up-regulated and 3 were down-regulated after 6 h stretch. There were 12 up-regulated and 2 down-regulated genes after 24 h stretch. These differentially expressed genes included genes encoding cell-cell adhesion molecules (CD44, ICAM1), cell-matrix adhesion molecules (ITGA5, ITGA6, ITGAL, ITGB2, SPP1), basement membrane constituents (SPARC, TNC), collagens and ECM constituents (COL5A1, COL11A1, FN1), ECM proteases (ADAMTS1, ADAMTS8, MMP8) and inhibitors (TIMP1), as well as other adhesion-related molecules (CTGF, CTNND2, TGFBI, CLEC3B). Both the cytosolic and membrane integrin α5 protein levels were up-regulated in response to stretch. CONCLUSION: This study identified several force-sensitive genes related to ECM and adhesion in stretched human PDL cells and should facilitate future studies on the stretch-induced cell realignment and mechanic force related periodontal remodelling by providing potential target genes.

Cyclic stretch influenced expression of membrane connexin 43 in human periodontal ligament cell.

OBJECTIVE: Periodontal ligament (PDL) cells play an important role in preserving periodontal homeostasis and periodontal remodelling in response to mechanical stimulations. Gap junction intercellular communication (GJIC) is essential for homeostasis and many other biological processes of multicellular organisms. While the role of GJIC in mechanotransduction of PDL cells remains largely unknown. In the present study, we examined the influence of cyclic stretch on the expression of membrane gap junction protein connexin 43 (Cx43) in cultured human PDL cells. DESIGN: Cultured human PDL cells were exposed to 1%, 10% and 20% stretch strains for 0.5 h, 1 h and 24 h. Then the membrane Cx43 protein expression was measured by flow cytometry and the Cx43 mRNA level was measured by real-time polymerase chain reaction. RESULTS: Half hour and 1 h cyclic stretches with strains up to 20% did not change the expression of membrane Cx43 protein, while 24 h cyclic stretches with 10% and 20% strains down-regulated the expression of membrane Cx43 protein in a strain magnitude-dependent manner. Furthermore, cyclic stretch also changed the Cx43 mRNA level and induced realignment in cells. CONCLUSION: The present research provide the first evidence that cyclic stretch influenced the membrane Cx43 protein expression in cultured human PDL cells.