An evidence of Humanin-like peptide and Humanin mediated cryosurvival of spermatozoa in buffalo bulls.

Buffalo spermatozoa are vulnerable to cryo-injuries due to inherent deficiency of endogenous antioxidants, high polyunsaturated fatty acids (PUFA) content in plasma membrane and low cholesterol/phospholipid (C/P) ratio. Humanin is a potent cytoprotective agent that protects the cells against oxidative stress and apoptosis. The present study was designed to establish the presence of Humanin in buffalo and effect of Humanin supplementation on freezability of buffalo spermatozoa. Indirect immunofluorescence test revealed presence of Humanin in ejaculated and epididymal spermatozoa, and, elongated spermatids and interstitial space in the testicular tissue section. Humanin levels in seminal plasma were significantly and positively correlated with sperm concentration and individual progressive motility (IPM) in good (n = 22; IPM >70%) and poor (n = 10; IPM <50%) quality ejaculates. For supplementation studies, a total of 24 ejaculates (IPM ≥70%) were collected and each ejaculate was then divided into four aliquots. First aliquot was diluted with egg yolk-tris-glycerol (EYTG) extender without Humanin and served as control group (Group I). Rest three aliquots were diluted with extender containing 2 (Group II), 5 (Group III) and 10 µM Humanin (Group IV), respectively. Semen was cryopreserved using standard protocol and evaluated at pre-freeze for lipid peroxidation (LPO) and post-thaw stages for spermatozoa kinematics, LPO, mitochondrial membrane potential (MMP), capacitation, apoptotic status and DNA integrity. The treatment group that showed best results (5 µM) was compared with control group for in vitro fertility assessment by homologous zona binding assay. The LPO levels were lower (p < 0.05) in 5 and 10 µM Humanin supplemented group. The MMP and DNA integrity were higher (p < 0.05) in 5 µM group than other groups. F-pattern was higher (p < 0.05) and B-pattern was lower (p < 0.05) in 5 and 10 µM Humanin supplemented groups. Lower apoptotic and higher viable spermatozoa (p < 0.05) were observed in 5 µM Humanin group. The mean number of spermatozoa bound to zona pellucida was higher (p < 0.05) in 5 µM Humanin treated group than the control group. The study established the presence of Humanin in buffalo spermatozoa and seminal plasma for very first time and concluded that Humanin supplementation at 5 µM concentration improves the freezability and in vitro fertility of buffalo spermatozoa.

Cryoprotectant with a mitochondrial derived peptide, humanin, improves post-thaw quality of buffalo spermatozoa.

BACKGROUND: Semen cryopreservation results in deleterious effects on spermatozoa, including lipid peroxidation and a reduction in the total antioxidant components of seminal plasma. The ultimate outcome of these changes is a reduction in post-thaw semen quality. A mitochondrial derived peptide, humanin, a potent cytoprotective and antioxidant agent was used in the present study. OBJECTIVE: To evaluate the efficacy of a mitochondrial-derived peptide, humanin to improve the post-thaw quality of buffalo spermatozoa. MATERIALS AND METHODS: A total of 18 ejaculates from three Murrah buffalo bulls (n=6 each) were collected. Each ejaculate was divided into four aliquots. The first aliquot was diluted with standard EYTG dilutor (Group I, control), whereas the other three aliquots were diluted with EYTG supplemented with 2 µM (Group II), 5 µM (Group III) and 10 µM humanin (Group IV), respectively. Semen was evaluated for physico-morphological and functional attributes such as progressive motility, viability, abnormality, acrosome integrity, plasmamembrane integrity of fresh samples, pre-freeze and post-thaw stages. Oxidative stress parameters [lipid peroxidation (LPO) and total antioxidant capacity (TAC)] were also measured at the pre-freeze and post-thaw stages. RESULTS: Humanin supplementation resulted in significantly higher (p < 0.05) post-thaw motility in all treatment groups and, higher (p < 0.05) viability in Groups III and IV in comparison to the control at the post-thaw stage. Spermatozoa with intact acrosome and plasma membrane were higher (p < 0.05) in Groups III and IV as compared to Groups I and II. The LPO levels at the post-thaw stage were found to be lower (p < 0.05) in all treatment groups versus the control group, whereas, higher (p≤0.05) TAC values were recorded in Groups III and IV in comparison to the control and Group II. CONCLUSION: Humanin supplementation in the extender improved the freezabilty of buffalo spermatozoa.

Pancreatic cancer prognosis is predicted by an ATAC-array technology for assessing chromatin accessibility.

Unlike other malignancies, therapeutic options in pancreatic ductal adenocarcinoma (PDAC) are largely limited to cytotoxic chemotherapy without the benefit of molecular markers predicting response. Here we report tumor-cell-intrinsic chromatin accessibility patterns of treatment-naïve surgically resected PDAC tumors that were subsequently treated with (Gem)/Abraxane adjuvant chemotherapy. By ATAC-seq analyses of EpCAM+ PDAC malignant epithelial cells sorted from 54 freshly resected human tumors, we show here the discovery of a signature of 1092 chromatin loci displaying differential accessibility between patients with disease free survival (DFS) < 1 year and patients with DFS > 1 year. Analyzing transcription factor (TF) binding motifs within these loci, we identify two TFs (ZKSCAN1 and HNF1b) displaying differential nuclear localization between patients with short vs. long DFS. We further develop a chromatin accessibility microarray methodology termed "ATAC-array", an easy-to-use platform obviating the time and cost of next generation sequencing. Applying this methodology to the original ATAC-seq libraries as well as independent libraries generated from patient-derived organoids, we validate ATAC-array technology in both the original ATAC-seq cohort as well as in an independent validation cohort. We conclude that PDAC prognosis can be predicted by ATAC-array, which represents a low-cost, clinically feasible technology for assessing chromatin accessibility profiles.

Author Correction: Room-temperature valley coherence in a polaritonic system.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Room-temperature valley coherence in a polaritonic system.

The emerging field of valleytronics aims to coherently manipulate an electron and/or hole's valley pseudospin as an information bearing degree of freedom (DOF). Monolayer transition metal dichalcogenides, due to their strongly bound excitons, their degenerate valleys and their seamless interfacing with photons are a promising candidate for room temperature valleytronics. Although the exciton binding energy suggests room temperature valley coherence should be possible, it has been elusive to-date. A potential solution involves the formation of half-light, half-matter cavity polaritons based on 2D material excitons. It has recently been discovered that cavity polaritons can inherit the valley DOF. Here, we demonstrate the room temperature valley coherence of valley-polaritons by embedding a monolayer of tungsten diselenide in a monolithic dielectric cavity. The extra decay path introduced by the exciton-cavity coupling, which is free from decoherence, is the key to room temperature valley coherence preservation. These observations paves the way for practical valleytronic devices.

Phase-pure VO2 nanoporous structure for binder-free supercapacitor performances.

Vanadium oxides are anticipated as a high-performance energy storage electrode due to their coupled double layer and pseudo-capacitative charge storage mechanism. In the present work, we investigated the influence of different structural phases of as-grown VO2 nanoporous structure and corresponding oxidation states on the supercapacitor performance. This nanoporous structure facilitates fast ion diffusion and transport. It is shown that stoichiometric monoclinic VO2, with V oxidation state of +4, provides superior charge storage capacity with a capacitance value of 33 mF/cm2, capacitance retention of 93.7% and Coulombic efficiency of 98.2%, to those for VO2 structures with mixed oxidation states of V5+ and V4+. A comparable high energy density is also recorded for the sample with all V4+. Scanning Kelvin probe microscopy results clarify further the formation of space charge region between VO2 and carbon paper. These key findings indicate the potentiality of binder-free single phase monoclinic VO2 porous structure towards the next-generation micro-supercapacitor application.

Blood clotting and traumatic injury with shock mediates complement-dependent neutrophil priming for extracellular ROS, ROS-dependent organ injury and coagulopathy.

Polymorphonuclear (PMN) leucocytes participate in acute inflammatory pathologies such as acute respiratory distress syndrome (ARDS) following traumatic injury and shock, which also activates the coagulation system systemically. Trauma can prime the PMN nicotinamide adenine dinucleotide phosphate (NADPH) oxidase complex for an enhanced respiratory burst, but the relative role of various priming agents in this process remains incompletely understood. We therefore set out to identify mediators of PMN priming during coagulation and trauma-shock and determine whether PMN reactive oxygen species (ROS) generated in this manner could influence organ injury and coagulation. Initial experiments demonstrated that PMN are primed for predominantly extracellular ROS production by products of coagulation, which was abrogated by CD88/C5a receptor(C5aR) inhibition. The importance of this was highlighted further by demonstrating that known PMN priming agents result in fractionally different amounts of extracellular versus intracellular ROS release depending on the agent used. Plasma from trauma patients in haemodynamic shock (n = 10) also primed PMN for extracellular ROS in a C5a-dependent manner, which correlated with both complement alternative pathway activation and thrombin generation. Furthermore, PMN primed by preincubation with products of blood coagulation directly caused loss of endothelial barrier function in vitro that was abrogated by C5aR blockade or NADPH oxidase inhibition. Finally, we show in a murine model of trauma-shock that p47phox knock-out (KO) mice with PMN incapable of generating ROS were protected from inflammatory end-organ injury and activated protein C-mediated coagulopathy. In summary, we demonstrate that trauma-shock and coagulation primes PMN for predominantly extracellular ROS production in a C5a-dependent manner that contributes to endothelial barrier loss and organ injury, and potentially enhances traumatic coagulopathy.

Atom probe tomography data analysis procedure for precipitate and cluster identification in a Ti-Mo steel.

An atom probe tomography data analysis procedure for identification of particles in a Ti-Mo steel is presented. This procedure has been used to characterise both carbide precipitates (larger particles) and solute clusters (smaller particles), as reported in an accompanying Mater. Sci. Eng. A paper [1]. Particles were identified using the maximum separation method (cluster-finding algorithm) after resolving peak overlaps at several locations in the mass spectrum. The cluster-finding algorithm was applied to the data in a two-stage process to properly identify particles having a bimodal size distribution. Furthermore, possible misidentification of matrix atoms (mainly Fe) due to the local magnification effect (from the difference in field evaporation potential between the matrix and precipitates) has been resolved using an atomic density approach, comparing that measured experimentally using APT to the theoretical density of both the matrix and particles.

Effect of testicular tissue lysate on developmental competence of porcine oocytes matured and fertilized in vitro.

The objective of the present study was to investigate the effect of testicular tissue lysate (TTL) on developmental competence of germinal vesicle (GV) stage porcine oocytes. Two types of TTL were prepared through repeated freeze-thaw in liquid nitrogen, one from whole testicular tissue (wTTL) and other from either of four different sections of testes, namely just beneath the tunica albuginea (TA), from the transitional area between the seminiferous cord/tubules and the mediastinum testis (TR) and from the intermediate area (parenchymal tissue origin) and CE (cauda epididymis origin). The whole or section-wise TTL treatments were given for 44 hr during in vitro maturation (IVM). Oocyte maturation was done in either of the two media, namely defined (high-performance basic medium for porcine oocyte maturation, commercially available) and serum containing (TCM199). After maturation, oocytes were co-incubated with fresh spermatozoa for 6 hr and then transferred to embryo culture media. Treatment of GV stage oocytes with wTTL (1 mg/ml) increased the cleavage and morula percentage rate (69.23 ± 6.23 and 48.15 ± 6.77, respectively) than that of their control (58.33 ± 8.08 and 32.54 ± 5.53, respectively) in defined media, and in serum-containing media, cleavage and morula percentage rate were almost equal in both treatment (54.56 ± 7.79 and 34.70 ± 6.78, respectively) and control (59.52 ± 8.21 and 38.52 ± 6.54, respectively). However, effect of wTTL was not significant. In case of section-wise TTL supplements, TR section significantly (p < .01) improved cleavage and morula rate (58.43 ± 7.98 and 36.14 ± 6.89, respectively) followed by TA. In conclusion, present study indicates that IVM, in vitro fertilization and in vitro culture of embryo are improved in the presence of TTL, particularly its TR section. Further study is expected to reveal the principal components of TTL which may prove useful for IVM.

Steroid and metabolic hormonal profile of porcine serum vis-à-vis ovarian follicular fluid.

AIM: This study was conducted to understand whether serum level of the steroid and metabolic hormones may be indicative of their level in ovarian follicular fluid (FF) in porcine, and its influence on fertility. MATERIALS AND METHODS: Ovaries from pigs (n=32) of two genetic groups, namely, native (Ghungroo; n=16) and crossbred (Hampshire × Ghungroo; n=16) were collected. Both the genetic groups comprised gilts (n=8) and sows (n=8), and sows were in luteal phase of estrus cycle. FF was aspirated from small, medium and large follicles, and centrifuged for the collection of supernatant for further analysis. Blood samples were collected from the same animals, and serum was separated. Hormones, namely, cortisol, T3, T4 and testosterone were estimated by radioimmunoassay. Two-way ANOVA was used for analysis of data considering genetic background (native or crossbred), stage of reproductive life (gilt or sow), and source of sample (serum or FF) as fixed effects. RESULTS: It was observed that all the hormones except cortisol differed significantly (p<0.01) based on genetic background. Stage of reproductive life and source of sample did not affect the studied hormonal level. Within the genetic groups, stage of reproductive life influenced T3 (p<0.01), cortisol (p<0.05) and testosterone (p<0.01) level in crossbred pigs as compared to T3 (p<0.01) only in native pigs. The level of T3 in serum, as well as FF, was higher (p<0.01) in Ghungroo gilts compared to sows. However, a reverse of this was observed in the case of crossbred pigs. The level of cortisol (p<0.05) and testosterone (p<0.01) was higher in crossbred sows than gilts in both serum and FF. CONCLUSION: The study revealed that serum level of the steroid and metabolic hormones is indicative of their level in the ovarian FF. Further, varying level of steroid and metabolic hormones in pigs based on genetic background may be due to variation in body size, rate of energy metabolism and stage of (re)productive life.

Gene expression and silencing of activin receptor type 2A (ACVR2A) in myoblast cells of chicken.

Activin receptor type 2A (ACVR2A) acts as receptor for myostatin (MSTN) protein involved in inhibiting satellite cell proliferation and differentiation. The importance of the ACVR2A gene during embryonic and post-hatch periods in broiler and layer chicken was studied in an in vitro cell culture system. The expression pattern of the ACVR2A gene during embryonic stages was similar in broiler and layer lines. Post-hatch expression of the ACVR2A gene varied significantly between broiler and layer lines. Five shRNA molecules were designed to knockdown expression of the ACVR2A gene in chicken myoblast cells. The silencing of the ACVR2A gene in a cell culture system varied from 60% to 82%. It is concluded that between broiler and layer lines, there were no significant changes in expression of the ACVR2A gene during embryonic stages but it varied significantly during the post-hatch period. The shRNA showed silencing of the ACVR2A gene under an in vitro cell culture system.

Optimized weak measurements of Goos-Hänchen and Imbert-Fedorov shifts in partial reflection.

The spatial and the angular variants of the Imbert-Federov (IF) beam shifts and the angular Goos-Hänchen (GH) shift contribute in a complex interrelated way to the resultant beam shift in partial reflection at planar dielectric interfaces. Here, we show that the two variants of the IF effects can be decoupled and separately observed by weak value amplification and subsequent conversion of spatial ↔angular nature of the beam shifts using appropriate pre and post selection of polarization states. Such optimized weak measurement schemes also enable one to nullify one effect (either the GH or the IF) and exclusively observe the other. We experimentally demonstrate this and illustrate various other intriguing manifestations of optimized weak measurements in elliptical and / or linear polarization basis. We also present a Poincare sphere based analysis on conversion / retention of the angular or spatial nature of the shifts with pre and post selection of states in weak measurement. The demonstrated ability to amplify, controllably decouple or combine the beam shifts via weak measurements may prove to be valuable for understanding the different physical contributions of the effects and for their applications in sensing and precision metrology.

Development of a new system for guidewire-assisted tracheal intubation: manikin and cadaver evaluation.

Guided intubation using a tracheal tube and semi-rigid introducer is associated with technical difficulties, failure and traumatic complications. We describe the development of a new system of guidewire-assisted tracheal intubation that may circumvent these problems. A reinforced silicone tracheal tube was modified with a guide channel built inside its wall, and a nitinol non-kinking guidewire was matched to this channel. Both anterograde and retrograde tracheal intubation were evaluated in a test rig, an airway manikin and then in preserved and fresh cadavers. There was minimal resistance to passage of the guidewire through the guide channel when the modified tube was in an anatomical configuration, in contrast to moderate resistance when an Airway Exchange Catheter was passed through a PVC tracheal tube. Intubation using the new equipment required increased force in the manikin and preserved cadavers, but minimal force in fresh cadavers. Resistance to tracheal tube advancement in preserved cadavers was overcome by withdrawal followed by 90° rotation, but this manoeuvre was not required in fresh cadavers. We suggest that the combination of the modified tracheal tube and matching guidewire may allow easy and reliable single-step guided tracheal intubation when used in patients.

Topological defect transformation and structural transition of two-dimensional colloidal crystals across the nematic to smectic-A phase transition.

We observe that topological defects in nematic colloids are strongly influenced by the elasticity and onset of smectic layering across the nematic (N) to smectic-A (SmA) phase transition. When approaching the SmA phase from above, the nematic hyperbolic hedgehog defect that accompanies a spherical colloidal inclusion is transformed into a focal conic line in the SmA phase. This phase transformation has a strong influence on the pairwise colloidal interaction and is responsible for a structural transition of two-dimensional colloidal crystals. The pretransitional behavior of the point defect is supported by Landau-de Gennes Q-tensor modeling accounting for the increasing elastic anisotropy.

Catalyst free growth of ZnO nanowires on graphene and graphene oxide and its enhanced photoluminescence and photoresponse.

We demonstrate the graphene assisted catalyst free growth of ZnO nanowires (NWs) on chemical vapor deposited (CVD) and chemically processed graphene buffer layers at a relatively low growth temperature (580 °C) in the presence and absence of ZnO seed layers. In the case of CVD graphene covered with rapid thermal annealed ZnO buffer layer, the growth of vertically aligned ZnO NWs takes place, while the direct growth on CVD graphene, chemically derived graphene (graphene oxide and graphene quantum dots) without ZnO seed layer resulted in randomly oriented sparse ZnO NWs. Growth mechanism was studied from high resolution transmission electron microscopy and Raman spectroscopy of the hybrid structure. Further, we demonstrate strong UV, visible photoluminescence (PL) and enhanced photoconductivity (PC) from the CVD graphene-ZnO NWs hybrids as compared to the ZnO NWs grown without the graphene buffer layer. The evolution of crystalinity in ZnO NWs grown with ZnO seed layer and graphene buffer layer is correlated with the Gaussian line shape of UV and visible PL. This is further supported by the strong Raman mode at 438 cm(-1) significant for the wurtzite phase of the ZnO NWs grown on different graphene substrates. The effect of the thickness of ZnO seed layers and the role of graphene buffer layers on the aligned growth of ZnO NWs and its enhanced PC are investigated systematically. Our results demonstrate the catalyst free growth and superior performance of graphene-ZnO NW hybrid UV photodetectors as compared to the bare ZnO NW based photodetectors.

Influence of boron addition to Ti-13Zr-13Nb alloy on MG63 osteoblast cell viability and protein adsorption.

Cell proliferation, cell morphology and protein adsorption on near ß-type Ti-13Zr-13Nb (TZN) alloy and Ti-13Zr-13Nb-0.5B (TZNB) composite have been investigated and compared to evaluate the effect of boron addition which has been added to the Ti alloy to improve their poor tribological properties by forming in situ TiB precipitates. MG63 cell proliferation on substrates with different chemistry but the same topography was compared. The MTT assay test showed that the cell viability on the TZN alloy was higher than the boron containing TZNB composite after 36 h of incubation and the difference was pronounced after 7 days. However, both the materials showed substantially higher cell attachment than the control (polystyrene). For the same period of incubation in fetal bovine serum (FBS), the amount of protein adsorbed on the surface of boron free TZN samples was higher than that in the case of boron containing TZNB composite. The presence of boron in the TZN alloy influenced protein adsorption and cell response and they are lower in TZNB than in TZN as a result of the associated difference in chemical characteristics.

Laser-driven microflow-induced bistable orientation of a nematic liquid crystal in perfluoropolymer-treated unrubbed cells.

We demonstrate laser-driven microflow-induced orientational change (homeotropic to planar) in a dye-doped nematic liquid crystal. The homeotropic to planar director alignment is achieved in unrubbed cells in the thermal hysteresis range of a discontinuous anchoring reorientation transition due to the local heating by light absorption in dye-doped sample. Various bistable patterns were recorded in the cell by a programmable laser tweezers. The width of the patterns depend on the scanning speed of the tightly focussed laser beam and the minimum width obtained is approximately equal to 0.57µm which is about 35 times smaller than the earlier report in the rubbed cells. We show that the motion of the microbeam spot causes local flow as a result the liquid crystal director is aligned along that direction.

UV induced zener diode characteristic in a single n-ZnO/p++-Si nanoheterojunction.

Rectification is observed in a single n-ZnO/p++-Si nanoheterojunction using ultra high vacuum compatible scanning tunneling microscope. The nanohetrojunctions have been grown using catalyst free vapor-solid growth of ZnO nanorods on p++-Si substarte. A high rectification ratio approximately 100 at 2 V is observed in the current voltage measurements. Temperature dependent study in these nanohetero-junctions showed activation energy for carrier conduction approximately 66 meV, which is primarily associated to the presence of heterojunction induced interface states. Role of ultra violet excitation on these finite sized (approximately 500 nm) nanoheterojunction is also studied with photo-generated electron-hole pairs. A Zener breakdown is observed in this photo-excitation process. Increase in the concentration of minority carriers and corresponding decrease in barrier width and height at the junction have been identified for the observed tunneling behavior under UV illumination. The large carrier concentration in the finite sized device with large diffusion length of electron (approximately 2 microm) is made responsible for the observed voltage regulation.

Influence of in situ TiB reinforcements and role of heat treatment on mechanical properties and biocompatibility of ß Ti-alloys.

The effect of heat treatment on the mechanical properties of Ti-35Nb-5.7Ta-7.2Zr (TNZT) and Ti-35Nb-5.7Ta-7.2Zr-0.5B (TNZTB) alloys has been investigated. In the case of TNZT alloy, the presence of ω phase in the matrix has a greater effect on strength and hardness than the presence of secondary α precipitates. The TNZTB alloy shows higher hardness and tensile strength than the TNZT alloy due to the formation of hard TiB precipitates in the matrix of the former. However, the boron free alloy offers higher ductility than the boron containing alloy. Presence of TiB precipitates in the matrix increases the strength of the TNZTB alloy when ω precipitates are present in the matrix. However, the boride precipitates have no substantial influence on the strength of the TNZTB alloy when ω phase in the matrix is replaced by the α phase. The elastic modulus of the TNZT samples shows a very small variation with different heat treatment conditions. The TNZT alloy samples containing ß and ω phases show higher elastic modulus than the samples containing ß and α phases. The elastic modulus of the TNZTB alloy is higher than that of the TNZT alloy due to the formation of high modulus TiB particles in the matrix. Both the alloys show better cell adhesion and spreading than the control material (polystyrene). However, the boron free Ti-alloy shows better cell attachment than the boron containing Ti-alloy.