The smallest triple-ring tubular gold clusters M2@Au15 with M = Mo, W: stability, electronic properties and nonlinear optical response.

The smallest triple ring tube-like gold clusters M2@Au15q with M = Mo, W and q = 1, 0, -1 are reported for the first time. Incorporation of an M2 dimer results in a remarkable modification of both atomic and electronic structures of the gold host. While the bare Au15 cluster exhibits a 3D cage shape, the doubly doped clusters M2@Au15 in all charge states are found to prefer a tubular form composed of three five-membered Au rings in an anti-prism arrangement and stabilized by an M2 unit placed inside the tube-like Au15 gold framework. The equilibrium geometry of both M2@Au15 and M2@Au15- is not much modified upon electron detachment from or attachment to their pure gold counterpart. The anion M2@Au15- with 28 itinerant electrons establishes an electron shell configuration of 1S21P61D102S21F8, in which the 1F shell splits into four different sub-levels. These stable clusters are thus not magic. Computed results on the first and second hyper-polarizability parameters of the doped clusters show a strong dependence on the charge. Overall, the neutral M2@Au15 is found to exhibit a particularly strong nonlinear optical (NLO) response. These clusters can also be extended to 1D nanowires, providing helpful guidance for the design of novel gold-based nanowires with rich optoelectronic properties.

Two New Benzoquinone Derivatives from Vietnamese Knema globularia Stems.

The chemical investigation of the stems of Knema globularia led to the isolation of two new benzoquinones derivatives, embenones A and B (1 and 2), along with three known compounds (3-5). The structures of the isolated compounds were determined using spectroscopic techniques, including HRESIMS, 1D and 2D NMR, in conjunction with comparison to existing literature data. Compounds 1 and 2 represent new carbon skeletons in nature. Furthermore, all isolated compounds were evaluated for their α-glucosidase inhibitory activity, with compounds 1-3 exhibiting superior potency relative to the positive control (acarbose, IC50 331 µM). Their IC50 values ranged from 1.40 to 96.1 µM.

Bio-Guided Isolation of Alpha-Glucosidase Inhibitory Compounds from Vietnamese Lichen Roccella Montagnei.

A bio-guided isolation was applied to the Vietnamese lichen Roccella montagnei based on alpha-glucosidase inhibition. Six compounds were isolated and structurally elucidated, including a new ortho depside, montagneside A (1), together with five known compounds, sekikaic acid (2), lanost-7-en-3ß-ol (3), ethyl orsellinate (4), D-montagnetol (5), and D-erythrin (6). Their chemical structures were identified by extensive 1D and 2D NMR analysis, high-resolution mass spectroscopy, and comparisons with those reported in the literature. D-Erythrin (6), a major component, was selected for further modification using Smiles rearrangement. Three erythritol derivatives 6a-6c were synthesized. Compounds 1-3, 6, and 6a-6c were evaluated for alpha-glucosidase inhibition. Compounds 2 and 6a-6c showed significant alpha-glucosidase inhibition with IC50 values ranging from 7.9 to 149 µM, respectively. Molecular docking was applied to the most active compound 6a to clarify the inhibitory mechanism.

A comparison between the enzymatic oxidation method and headspace gas chromatography with a flame ionization detector in the determination of postmortem blood ethanol.

Ethanol is the most commonly encountered substance in forensic toxicology. Determining blood alcohol concentration (BAC) in autopsies accounts for the majority of work in forensic diagnosis. The most common method to assess BAC is the enzymatic oxidation method because of its low cost, easy operation, and high throughput. Still, the elevated lactate and lactate dehydrogenase (LDH) levels in postmortem blood may affect accuracy. This study uses headspace gas chromatography with a flame ionization detector (HS-GC/FID) to assess the interference of lactate and LDH levels on BAC in 110 autopsied blood samples determined by the enzymatic oxidation method. The results showed that lactate and LDH levels in postmortem blood were higher than in normal blood. There was a weak correlation between the lactate levels and BAC difference (r = 0.23, p < 0.05) and a strong correlation between LDH levels and BAC difference (r = 0.67, p < 0.001). The differentiation of BAC between the enzymatic oxidation method and HS-GC/FID was significant (p < 0.001), confirming the interference significantly. All postmortem blood samples with lactate and LDH levels higher than regular lead to a positive error in determining BAC by enzymatic oxidation method. The study results suggest that the HS-GC/FID method should be used to determine BAC in postmortem blood samples instead of the enzymatic oxidation method to avoid mistakes in forensic diagnosis.

A simple and effective scaffold for mouse hepatic stellate cell primary culture.

Scaffold-based culture is necessary for hepatic stellate cells (HSCs) because HSCs are promptly autoactivated under plastic conditions. Our research aims to investigate the potential and role of fibrin scaffold in reducing autoactivation, maintaining cell function, and extending the in vitro culture time of primary HSCs. HSCs were isolated from BALB/c mice and cultured on the surface of plastic, Matrigel, and fibrin gel. HSC's characteristics, including recovery, morphology, proliferation, lipid droplet (LD) storage, and activation were evaluated. Cell recovery was 86%, 80%, and 60% in fibrin, Matrigel, and plastic, respectively (P < 0.05). HSCs cultured on a plastic dish were autoactivated until day 7 with high proliferation, loss of cytoplasmic LD lipid droplets, and increased expression of activation markers, including alpha-smooth muscle actin (α-sma) and collagen type I. In contrast, these phenomena were reduced in Matrigel and fibrin-based cultures (P < 0.05). HSC culture in fibrin scaffold was associated with altered expression of cell adhesion molecules, including increased E-cadherin and inhibited N-cadherin. HSCs were more stellate-like in morphology in fibrin than in the Matrigel scaffold. Interestingly, fibrin-scaffold-embedded culture was able to maintain HSC quiescent state for up to 14 days in vitro. Fibrin gel could provide a potential scaffold for primary HSC culture while preserving cell function and extending primary HSC in vitro culture time.NEW & NOTEWORTHY Fibrin gel is appropriate for maintaining quiescence characteristics in primary culture of mouse hepatic stellate cells. Embedded culture of hepatic stellate cells in fibrin gel simulates in vivo cell morphology. Stiffness and adhesion molecules of fibrin gel play a crucial role in the hepatic stellate cell's primary culture.

Evidence that the catalytic mechanism of heme a synthase involves the formation of a carbocation stabilized by a conserved glutamate.

In eukaryotes and many aerobic prokaryotes, the final step of aerobic respiration is catalyzed by an aa3-type cytochrome c oxidase, which requires a modified heme cofactor, heme a. The conversion of heme b, the prototypical cellular heme, to heme o and ultimately to heme a requires two modifications, the latter of which is conversion of a methyl group to an aldehyde, catalyzed by heme a synthase (HAS). The N- and C-terminal halves of HAS share homology, and each half contains a heme-binding site. Previous reports indicate that the C-terminal site is occupied by a heme b cofactor. The N-terminal site may function as the substrate (heme o) binding site, although this has not been confirmed experimentally. Here, we assess the role of conserved residues from the N- and C-terminal heme-binding sites in HAS from prokaryotic (Shewanella oneidensis) and eukaryotic (Saccharomyces cerevisiae) species - SoHAS/CtaA and ScHAS/Cox15, respectively. A glutamate within the N-terminal site is found to be critical for activity in both types of HAS, consistent with the hypothesis that a carbocation forms transiently during catalysis. In contrast, the residue occupying the analogous C-terminal position is dispensable for enzyme activity. In SoHAS, the C-terminal heme ligands are critical for stability, while in ScHAS, substitutions in either heme-binding site have little effect on global structure. In both species, in vivo accumulation of heme o requires the presence of an inactive HAS variant, highlighting a potential regulatory role for HAS in heme o biosynthesis.

A Multicenter Study of Clinicopathology and Immunohistochemical Distinction between Adult and Pediatric Large B-Cell Lymphoma.

Introduction: Pediatric DLBCL is considered a homogenous group and has superior outcomes compared to adults. This study investigated the clinical pathology and immunohistochemical distinction between adult and pediatric large B-cell lymphoma. Methods: A cross-sectional study of 314 NHLs with the morphology of diffuse pattern, large B-cell, and CD20 expression was investigated. Results: Of 314 cases, there were 6 cases of pleomorphic MCL (all in adults), 19 cases of Burkitt lymphoma (all in children), and 289 cases of DLBCL. Pediatric DLBCL had many striking differences: More frequency in extra-nodal sites; a higher proportion of centroblastic morphology; a predominance of GCB-type; a high proliferation rate; an infrequency of Bcl2 protein expression, and a lack of double-expresser lymphoma. Conclusions: Our study demonstrated the significant biological differences between adult and pediatric DLBCL.

Effects of autophagy inhibition by chloroquine on hepatic stellate cell activation in CCl4-induced acute liver injury mouse model.

BACKGROUND AND AIM: Hepatic stellate cells (HSCs) activation, a critical event in liver fibrosis, has been recently shown to be related to autophagy. Determine whether chloroquine (CQ) could affect (i) the activation of HSC in vivo and (ii) the hepatic damage in a mice acute liver injury model. METHODS: The acute liver injury was induced in BALB/c mice by carbon tetrachloride (CCl4 group); 24 h before and after CCl4 administration animals were treated by CQ (CCl4  + CQ group). As control, mice treated by olive oil were considered. After 48 h from CCl4 /olive oil administration, blood samples, liver tissues, and HSCs were harvested for analysis. RESULTS: In vivo, CQ attenuates CCl4 -induced acute liver damage as evidenced by (i) the reduction of liver enlargement, (ii) the reduction of liver swelling and necrosis also supported by a certain decrease of circulating transaminases level, and (iii) the reduction of liver fibrosis evaluated by collagen deposition and α-sma protein expression. In HSCs isolated from CQ treated group, we observed the inhibition of autophagy proved by the increase in p62 protein and the decrease of lc3 protein. In addition, CQ reduced the expression of the HSCs activation markers α-sma/collagen-I and down-regulated the expression of the proliferative marker ki67. CONCLUSION: The autophagy attenuation exerted by CQ together with the reduction of the expression of the proliferation marker in HSCs can lessen the acute liver damage potentially opening the way to novel therapeutic approaches for hepatic fibrosis.

Comprehensive guide to managing a chronic automated red cell exchange program in sickle cell disease.

Sickle cell disease (SCD) is associated with significant morbidity and mortality, and limits both the quality and quantity of life. Transfusion therapy, specifically automated red cell exchange (aRCE), plays a key role in management of SCD and is beneficial for certain indications in the chronic, outpatient setting. The approach to maintain a successful chronic aRCE program for SCD is multifaceted. This review will highlight important considerations including indications for aRCE, patient selection, transfusion medicine pearls, vascular access needs, complications of therapy, aRCE prescription, and therapy optimization. Moreover, the importance of a multidisciplinary approach with frequent communication between the services involved cannot be overstated. Ultimately, the underlying goal of a chronic RCE program is to improve the quality of life and longevity of patients with SCD.

Blocking olfactory input alters aggression in male and female California mice (Peromyscus californicus).

Olfactory input into the brain can be disrupted by a variety of environmental factors, including exposure to pathogens or environmental contaminants. Olfactory cues are often eliminated in laboratory rats and mice through highly invasive procedures like olfactory bulbectomy, which may also disrupt accessory olfactory pathways and detection of non-volatile odors. In the present study, we tested whether inducing anosmia through intranasal infusion of zinc gluconate alters aggression in a monogamous, biparental rodent species, the California mouse (Peromyscus californicus). This less invasive method of manipulating olfaction selectively targets the olfactory epithelium and reduces the detection of volatile odors. Treatment with zinc gluconate extended the time required for male and female California mice to find hidden pieces of apple and reduced the amount of time spent investigating bedding that was soiled by unfamiliar males. Moreover, inhibition of olfaction with zinc gluconate reduced aggressiveness in both sexes as demonstrated by an increased attack latency in the resident-intruder test among same-sex dyads from the same treatment group. These results suggest that volatile olfactory cues are necessary for agonistic responses in both male and female California mice. Therefore, even in species with complex social systems that include territorial aggression and monogamy, volatile olfactory cues modulate agonistic behavior.

Design and Optimization for a New XYZ Micropositioner with Embedded Displacement Sensor for Biomaterial Sample Probing Application.

An XYZ compliant micropositioner has been widely mentioned in precision engineering, but the displacements in the X, Y, and Z directions are often not the same. In this study, a design and optimization for a new XYZ micropositioner are developed to obtain three same displacements in three axes. The proposed micropositioner is a planar mechanism whose advantage is a generation of three motions with only two actuators. In the design strategy, the proposed micropositioner is designed by a combination of a symmetrical four-lever displacement amplifier, a symmetrical parallel guiding mechanism, and a symmetrical parallel redirection mechanism. The Z-shaped hinges are used to gain motion in the Z-axis displacement. Four flexure right-circular hinges are combined with two rigid joints and two flexure leaf hinges to permit two large X-and-Y displacements. The symmetrical four-lever displacement amplifier is designed to increase the micropositioner's travel. The displacement sensor is built by embedding the strain gauges on the hinges of the micropositioner, which is developed to measure the travel of the micropositioner. The behaviors and performances of the micropositioner are modeled by using the Taguchi-based response surface methodology. Additionally, the geometrical factors of the XYZ micropositioner are optimized by teaching-learning-based optimization. The optimized design parameters are defined with an A of 0.9 mm, a B of 0.8 mm, a C of 0.57 mm, and a D of 0.7 mm. The safety factor gains 1.85, while the displacement achieves 515.7278 µm. The developed micropositioner is a potential option for biomedical sample testing in a nanoindentation system.

The Drought-Mediated Soybean GmNAC085 Functions as a Positive Regulator of Plant Response to Salinity.

Abiotic stress factors, such as drought and salinity, are known to negatively affect plant growth and development. To cope with these adverse conditions, plants have utilized certain defense mechanisms involved in various aspects, including morphological, biochemical and molecular alterations. Particularly, a great deal of evidence for the biological importance of the plant-specific NAM, ATAF1/2, CUC2 (NAC) transcription factors (TFs) in plant adaptation to abiotic stress conditions has been reported. A previous in planta study conducted by our research group demonstrated that soybean (Glycine max) GmNAC085 mediated drought resistance in transgenic Arabidopsis plants. In this study, further characterization of GmNAC085 function in association with salt stress was performed. The findings revealed that under this condition, transgenic soybean plants overexpressing GmNAC085 displayed better germination rates than wild-type plants. In addition, biochemical and transcriptional analyses showed that the transgenic plants acquired a better defense system against salinity-induced oxidative stress, with higher activities of antioxidant enzymes responsible for scavenging hydrogen peroxide or superoxide radicals. Higher transcript levels of several key stress-responsive genes involved in the proline biosynthetic pathway, sodium ion transporter and accumulation of dehydrins were also observed, indicating better osmoprotection and more efficient ion regulation capacity in the transgenic lines. Taken together, these findings and our previous report indicate that GmNAC085 may play a role as a positive regulator in plant adaptation to drought and salinity conditions.

One-pot synthesis of manganese oxide/graphene composites via a plasma-enhanced electrochemical exfoliation process for supercapacitors.

In this work, a feasible one-pot approach to synthesize manganese oxide/graphene composites, the so-called plasma-enhanced electrochemical exfoliation process (PE3P), has been developed. Herein, a composite of graphene decorated with manganese oxide nanoparticles was prepared via PE3P from a KMnO4 solution and graphite electrode under a voltage of 70 V in an ambient environment. By controlling the initial KMnO4 concentration, we obtained distinct MnO2/graphene samples. The prepared samples were characterized by scanning electron microscopy, transmission electron microscopy, x-ray diffraction, x-ray photoelectron spectroscopy, and Raman spectroscopy. The electrochemical measurements of the MnO2/graphene composites revealed that the specific capacitance of the samples is approximately 320 F g-1 at a scan rate of 10 mV s-1, which is comparably very high for manganese oxide/carbon-based supercapacitor electrode materials. Considering the simple, low-cost, one-step and environmentally friendly preparation, our approach has the potential to be used for the fabrication of MnO2/graphene composites as the electrode materials of supercapacitors.

A global phylogeny of the fern genus Tectaria (Tectariaceae: Polypodiales) based on plastid and nuclear markers identifies major evolutionary lineages and suggests repeated evolution of free venation from anastomosing venation.

Tectaria (Tectariaceae) is one of the most confusing fern genera in terms of its circumscription and phylogeny. Since its original description, a number of genera had been moved into or related with this genus, while others had been segregated from it. Tectaria is also among the largest fern genera, comprising 150-210 mostly tropical species. Previous molecular studies have been far from comprehensive (sampling no more than 76 accessions from 52 species), limited in geographic scope (mainly restricted to Asia), and based exclusively on plastid markers. In the present study, DNA sequences of eight plastid and one nuclear marker of 360 accessions representing ca. 130 species of Tectaria, ca. 36 species of six non-Tectaria genera in Tectariaceae, 12 species of Davalliaceae, Oleandraceae, and Polypodiaceae, and 13 species of Lomariopsidaceae were used to infer a phylogeny with maximum likelihood, Bayesian inference, and maximum parsimony approaches. Our major results include: (1) the most recently proposed circumscription of Tectaria is strongly supported as monophyletic; (2) the genera Lenda, Microbrochis, Phlebiogonium, and Sagenia, sampled here for the first time, are resolved as part of Tectaria; (3) four superclades representing early splits in Tectaria are identified, with the Old World species being sister to the New World species; (4) 12 well-supported major clades in Tectaria are revealed, differing from one another in molecular, morphological, and geographical features; (5) evolution of 13 morphological characters is inferred in a phylogenetic context and morphological synapomorphies of various clades are identified; and in particular (6) free venation in Tectaria is inferred to be repeatedly derived from anastomosing venation, an evolutionary phenomenon not documented previously in vascular plants in a phylogenetic context based on both plastid and nuclear evidence.

Hands-off Time during Automated Chest Compression Device Application in Out-of-Hospital Cardiac Arrest: A Case Series Report.

INTRODUCTION: During out-of-hospital cardiac arrest (OHCA), chest compression interruptions or hands-off time (HOT) affect the prognosis. Our aim was to measure HOT due to the application of an automated chest compression device (ACD) by an advanced life support team. MATERIALS AND METHODS: This was a prospective observational case series report since the introduction of a new method of installing the ACD. Inclusion criteria were patients over 18 years old with OHCA who were treated with an ACD (Lucas 2(TM), Physio-Control). The ACD application was indicated only for OHCA patients transported to a hospital for Extra Corporeal Life Support (ECLS). We recorded the HOT related to switching from manual to mechanical chest compressions. An ACD consists of dorsal and ventral components, which can be installed either in one or in two steps, separated from a chest compression sequence. HOT was expressed as a median number of seconds [interquartile range]. RESULTS: From January 1, 2012 to January 15, 2013, 30 patients were included. In the case of ACD application in one phase (n = 16), the median HOT was 25.3 s [19.8-30.5]. With regard to patients with an ACD application in two phases (n = 14), the median HOT was, respectively, 9.8 s [7.8-17] and 12.4 s [9.5-16.2], that is, a median global HOT of 23.6 s [19-27.6]. HOT was not different between ACD applications in one or two phases (p = 0.52). For a two phase application, the median chest compression time between the two manipulations was 14.2 s [6.4-18]. CONCLUSION: There was no significant difference between techniques in the application of the Lucas 2(TM) device in terms of HOT. The short time needed to apply the device lends itself well to use as a primary chest compression modality during cardiac arrest as well as a bridge to novel resuscitation strategies (ECLS). A further study is currently underway with a larger number of ECLS patients.

Recovery of Acid Production in Streptococcus mutans Biofilms after Short-Term Fluoride Treatment.

Fluoride is commonly used as an ingredient of topical oral hygiene measures. Despite the anti-acidogenic activities of fluoride against cariogenic biofilms, the recovery of the biofilms from fluoride damage is unclear. Herein, we investigated the recovery of acid production in Streptococcus mutans biofilms after short-term or during periodic 1-min fluoride treatments. For this study, 46-hour-old S. mutans biofilms were treated with fluoride (0-2,000 ppm F-) for 1-8 min and then incubated in saliva for 0-100 min. The 74-hour-old biofilms were also periodically treated with the fluoride concentration during biofilm formation (1 min/treatment). Changes in acidogenicity and viability were determined via pH drop and colony-forming unit assays, respectively. In this study, acid production after a 1-min fluoride treatment was recovered as saliva incubation time increased, which followed a linear pattern of concentration dependence (R = 0.99, R2 = 0.98). The recovery pattern was in a biphasic pattern, with an initial rapid rate followed by a second slow recovery. Furthermore, recovery from fluoride damage was retarded in a concentration-dependent manner as treatment time increased. In periodic 1-min fluoride treatments, acid production in the biofilms was not diminished during the non-fluoride treatment period; however, it was reduced in a concentration-dependent manner during the fluoride treatment period. The viability of the biofilm cells did not change, even at high fluoride concentrations. Collectively, our results suggest that brief fluoride treatment does not sustain anti-acidogenic activity against S. mutans in biofilms since the damage is recoverable with time.

Shear-induced breaking of cages in colloidal glasses: Scattering experiments and mode coupling theory.

We employ x-ray scattering on sheared colloidal suspensions and mode coupling theory to study structure factor distortions of glass-forming systems under shear. We find a transition from quadrupolar elastic distortion at small strains to quadrupolar and hexadecupolar modes in the stationary state. The latter are interpreted as signatures of plastic rearrangements in homogeneous, thermalized systems. From their transient evolution with strain, we identify characteristic strain and length-scale values where these plastic rearrangements dominate. This characteristic strain coincides with the maximum of the shear stress versus strain curve, indicating the proliferation of plastic flow. The hexadecupolar modes dominate at the wavevector of the principal peak of the equilibrium structure factor that is related to the cage-effect in mode coupling theory. We hence identify the structural signature of plastic flow of glasses.

Chitosan-cinnamon beads enhance suppressive activity against Rhizoctonia solani and Meloidogyne incognita in vitro.

A novel chitosan-cinnamon bead carrier was prepared in this study. Chitosan was mixed with cinnamon powder (CP) and cinnamon extract (CE) to obtain chitosan-cinnamon powder (CCP) beads and chitosan-cinnamon extracted (CCE) beads, respectively. The potential antifungal and nematicidal activities of CCP and CCE were investigated against Rhizoctonia solani and Meloidogyne incognita in vitro. Relative antifungal activity of the CCP (5% CP) bead-treated R. solani was 30.9 and 23.9% after 1 and 2 day incubations, respectively. Relative antifungal activity of the CCE (0.5% CE) bead-treated R. solani was 4.3, 3.0 and 4.2% after 1, 2 and 3 days of incubation. Inhibition of hatch by CCP beads with CP of 5% was 78.8%. Inhibition of hatch by CCE beads with CE of 0.5% was 82.0%. J2 mortality following the CCP (5% CP) and CCE (0.5% CE) bead treatments was 85.0 and 95.8%, respectively against M. incognita after 48 h incubations.