A Role for GABAA Receptor β3 Subunits in Mediating Harmaline Tremor Suppression by Alcohol: Implications for Essential Tremor Therapy

Background

Essential tremor patients may find that low alcohol amounts suppress tremor. A candidate mechanism is modulation of α6β3δ extra-synaptic GABAA receptors, that in vitro respond to non-intoxicating alcohol levels. We previously found that low-dose alcohol reduces harmaline tremor in wild-type mice, but not in littermates lacking δ or α6 subunits. Here we addressed whether low-dose alcohol requires the β3 subunit for tremor suppression.

Methods

We tested whether low-dose alcohol suppresses tremor in cre-negative mice with intact β3 exon 3 flanked by loxP, and in littermates in which this region was excised by cre expressed under the α6 subunit promotor. Tremor in the harmaline model was measured as a percentage of motion power in the tremor bandwidth divided by overall motion power.

Results

Alcohol, 0.500 and 0.575 g/kg, reduced harmaline tremor compared to vehicle-treated controls in floxed β3 cre- mice, but had no effect on tremor in floxed β3 cre+ littermates that have β3 knocked out. This was not due to potential interference of α6 expression by the insertion of the cre gene into the α6 gene since non-floxed β3 cre+ and cre- littermates exhibited similar tremor suppression by alcohol.

Discussion

As α6β3δ GABAA receptors are sensitive to low-dose alcohol, and cerebellar granule cells express β3 and are the predominant brain site for α6 and δ expression together, our overall findings suggest alcohol acts to suppress tremor by modulating α6β3δ GABAA receptors on these cells. Novel drugs that target this receptor may potentially be effective and well-tolerated for essential tremor.

Highlights

We previously found with the harmaline essential tremor model that GABAA receptors containing α6 and δ subunits mediate tremor suppression by alcohol. We now show that β3 subunits in α6-expressing cells, likely cerebellar granule cells, are also required, indicating that alcohol suppresses tremor by modulating α6β3δ extra-synaptic GABAA receptors.

Determining hotspots of gaseous criteria air pollutants in Delhi airshed and its association with stubble burning

Transboundary pollutant transport is considered as one of the primary factors causing the seasonal air quality deterioration in Delhi, India's capital. The highest standard deviations exceeding days in winter for NO2 (7.14-9.63%) and SO2 (4.04-7.42%) in 2019-2022 underscore the role of meteorological conditions in Delhi's pollution. In contrast, the post-monsoon season shows the highest pollutant exceedance days (4.52-8.00%) for CO due to stubble burning (SB) in Punjab (68,902 fires/year). Despite the government's assertions of decreasing SB events (14.68%), the city's CO exceedance days persistently rose by 6.36%. CAMS data is used for assessing contribution hotspots through back-trajectory analysis at multiple heights. An overlap hotspot of 111 sq. km area is identified in the Southeast parts of Punjab that have a higher contribution to the CO levels in Delhi during the post-monsoon season of 2019. Similarly, hotspots are also observed for SO2 over industrial areas of Punjab during the post-monsoon and pre-monsoon seasons. The same seasons show similar contributing patterns for NO2 highlighting the influence of consistent emission patterns and meteorological conditions. The clear delineation of hotspots using the receptor model at multiple heights coupled with source apportionment studies will assist decision-makers in addressing the pollution sources outside Delhi.

Comparison of cycloplegia with atropine 1% versus cyclopentolate 1

PURPOSE

Cycloplegic refraction is mandatory for children to know the eye's refractive status. In this study, we compared cycloplegia induced by cyclopentolate 1% to that induced by atropine 1% by means of retinoscopy.

METHODS

In this parallel-designed interventional study, we included 67 children aged between 4 and 17 years. After the initial retinoscopy under cyclopentolate 1% (used twice in each eye), we repeated it a week later under atropine ointment 1% (used twice a day for 3 days); both were done by the same trained optometrist masked to the drug. Each eye's refraction was converted to spherical equivalents (SEs), and the values averaged between the two eyes of each child under each drug. We compared SE with paired t-test (JASP 16.4). In addition, we performed correlational analysis, and looked for agreement using the Bland-Altman plot. Significance was set at P < 0.05. Wherever possible, 95% confidence intervals (CIs) are quoted.

RESULTS

The mean SE with atropine was +1.93 ± 2.0 D, compared to +1.75 ± 1.95 D under cyclopentolate. On average, atropine induced greater cycloplegia by a mere 0.18 D (95% CI: 0.07 to 0.29 D, P value 0.002). The two cycloplegic refractions correlated significantly (Pearson's r: 0.975, P < 0.001). The Bland-Altman plot revealed the limits of agreement as 1.06 and -0.71 D.

CONCLUSION

Our study suggests that cyclopentolate works for the most part as well as atropine to attain cycloplegia. Atropine may be considered for children less than 15 years of age with greater than 5.0 D of hyperopia. Cycloplentolate, with its advantages of quick action and short duration, should form the first go-to topical cycloplegic in busy outpatient clinics.

Development of Hemagglutinin-Neuraminidase Homologous Peptides as Novel Promising Therapeutic Agents Against Peste des Petits Ruminants Virus

The lack of specific antiviral therapy and complications associated with the existing peste des petits ruminants (PPR) vaccines accentuates the search of novel antiviral blocking agents in order to curtail the PPR infection at initial level. The synthetic hemagglutinin-neuraminidase (HN) homologous peptides may compete with the natural HN protein of PPR virus for binding to signaling lymphocytic activation molecule (SLAM) receptor, consequently, may disrupt peste des petits ruminants virus (PPRV) at entry level. Therefore, insilico analysis, synthesis, purification and subsequent characterization of HN homologous peptides were conducted in this study. The HN homologous peptides were synthesized by means of solid phase chemistry and were purified by reversed-phase-high performance liquid chromatography. The mass as well as sequence of HN homologous peptides were assessed by mass spectroscopy while its secondary structure was elucidated by circular dichroism spectroscopy. The binding (interaction) efficacy of HN homologous peptides with PPRV antibodies was assessed via indirect enzyme linked immunosorbent assay, visual detection test (red wine to purple), bathochromic shift under UV-Vis spectrophotometry and lateral flow immunochromatographic strip test. The antiviral properties and cytotoxicity of these peptides were also assessed in B95a cell line with changes in cytopathic effect and titer of PPRV (Sungri/96). The presence of green fluorescein isothiocyanate over the B95a cell surface pointed towards the binding of HN homologous peptides with surface SLAM receptor. Moreover, the intact beta sheet configuration in water and lower cytotoxicity [cytotoxic concentration 50 (CC50) > 1000 µg/ml] of these peptides signifies its in vivo use. Among HN homologous peptides, the binding efficacy and antiviral properties of pep A was relatively high in comparison to pep B and Pep ppr peptides. The prerequisite concentration of HN homologous peptides (pep A = 12.5 µg/ml; pep B = 25 µg/ml; pep ppr = 25 µg/ml) to exemplify its antiviral effect was much lower than its CC50 level. Hence, this study signifies the therapeutic potential of synthetic HN homologous peptides.

Plant size, latitude, and phylogeny explain within-population variability in herbivory

Interactions between plants and herbivores are central in most ecosystems, but their strength is highly variable. The amount of variability within a system is thought to influence most aspects of plant-herbivore biology, from ecological stability to plant defense evolution. Our understanding of what influences variability, however, is limited by sparse data. We collected standardized surveys of herbivory for 503 plant species at 790 sites across 116° of latitude. With these data, we show that within-population variability in herbivory increases with latitude, decreases with plant size, and is phylogenetically structured. Differences in the magnitude of variability are thus central to how plant-herbivore biology varies across macroscale gradients. We argue that increased focus on interaction variability will advance understanding of patterns of life on Earth.

Search for Novel Therapies for Essential Tremor Based on Positive Modulation of α6-Containing GABAA Receptors

Background

Prior work using GABAA receptor subunit knockouts and the harmaline model has indicated that low-dose alcohol, gaboxadol, and ganaxolone suppress tremor via α6βδ GABAA receptors. This suggests that drugs specifically enhancing the action of α6βδ or α6βγ2 GABAA receptors, both predominantly expressed on cerebellar granule cells, would be effective against tremor. We thus examined three drugs described by in vitro studies as selective α6βδ (ketamine) or α6βγ2 (Compound 6, flumazenil) receptor modulators.

Methods

In the first step of evaluation, the maximal dose was sought at which 6/6 mice pass straight wire testing, a sensitive test for psychomotor impairment. Only non-impairing doses were used to evaluate for anti-tremor efficacy in the harmaline model, which was assessed in wildtype and α6 subunit knockout littermates.

Results

Ketamine, in maximally tolerated doses of 2.0 and 3.5 mg/kg had minimal effect on harmaline tremor in both genotypes. Compound 6, at well-tolerated doses of 1-10 mg/kg, effectively suppressed tremor in both genotypes. Flumazenil suppressed tremor in wildtype mice at doses (0.015-0.05 mg/kg) far lower than those causing straight wire impairment, and did not suppress tremor in α6 knockout mice.

Discussion

Modulators of α6βδ and α6βγ2 GABAA receptors warrant attention for novel therapies as they are anticipated to be effective and well-tolerated. Ketamine likely failed to attain α6βδ-active levels. Compound 6 is an attractive candidate, but further study is needed to clarify its mechanism of action. The flumazenil results provide proof of principle that targeting α6βγ2 receptors represents a worthy strategy for developing essential tremor therapies.

Highlights

We tested for harmaline tremor suppression drugs previously described as in vitro α6βδ or α6βγ2 GABAA receptor-selective modulators. Well-tolerated flumazenil doses suppressed tremor in α6-wildtype but not α6-knockout mice. Compound 6 and ketamine failed to display this profile, likely from off-target effects. Selective α6 modulators hold promise as tremor therapy.

Peptide-based immunotherapy in lupus: Where are we now?

In autoimmune rheumatic diseases, immune hyperactivity and chronic inflammation associate with immune dysregulation and the breakdown of immune self-tolerance. A continued, unresolved imbalance between effector and regulatory immune responses further exacerbates inflammation that ultimately causes tissue and organ damage. Many treatment modalities have been developed to restore the immune tolerance and immmunoregulatory balance in autoimmune rheumatic diseases, including the use of peptide-based therapeutics or the use of nanoparticles-based nanotechnology. This review summarizes the state-of-the-art therapeutic use of peptide-based therapies in autoimmune rheumatic diseases, with a specific focus on lupus.

Fabrication of thin Molybdenum backed target using rolling method

A successful attempt was made to fabricate a thin foil of natural Mo target on a thick Au backing with Indium in between to improve adhesion between the foils. Rolling at elevated temperature was considered to fabricate Mo foil while gold foil was fabricated employing conventional rolling technique. The heating of Mo foil under natural environment lead to the oxidation or carbonization on foil surface which was confirmed through Energy Dispersive X-ray Spectroscopy (EDS) measurements. Indium of thickness ∼86μg/cm² was evaporated on Mo foil to improve adhesion between Mo and Au foils. The characterization of fabricated thin Mo foil was done using the Energy Dispersive X-ray Spectroscopy (EDS) and the Scanning Electron microscope (SEM) techniques. Thickness measurement of the target (Mo-Au) was done using Energy Dispersive X-ray Fluorescence (EDXRF) technique, in the measurements the thickness of the Mo foil and of gold backing are found out to be 1.3 mg/cm² and 9 mg/cm² respectively.

Alcohol and Ganaxolone Suppress Tremor via Extra-Synaptic GABAA Receptors in the Harmaline Model of Essential Tremor

Background

A long-standing question is why essential tremor often responds to non-intoxicating amounts of alcohol. Blood flow imaging and high-density electroencephalography have indicated that alcohol acts on tremor within the cerebellum. As extra-synaptic δ-subunit-containing GABA_A receptors are sensitive to low alcohol levels, we wondered whether these receptors mediate alcohol's anti-tremor effect and, moreover, whether the δ-associated GABA_A receptor α6 subunit, found abundantly in the cerebellum, is required.

Methods

We tested the hypotheses that low-dose alcohol will suppress harmaline-induced tremor in wild-type mice, but not in littermates lacking GABA_A receptor δ subunits, nor in littermates lacking α6 subunits. As the neurosteroid ganaxolone also activates extra-synaptic GABA_A receptors, we similarly assessed this compound. The harmaline mouse model of essential tremor was utilized to generate tremor, measured as a percentage of motion power in the tremor bandwidth (9-16 Hz) divided by background motion power at 0.25-32 Hz.

Results

Ethanol, 0.500 and 0.575 g/kg, and ganaxolone, 7 and 10 mg/kg, doses that do not impair performance in a sensitive psychomotor task, reduced harmaline tremor compared to vehicle-treated controls in wild-type mice but failed to suppress tremor in littermates lacking the δ or the α6 GABA_A receptor subunit.

Discussion

As cerebellar granule cells are the predominant brain site intensely expressing GABA_A receptors containing both α6 and δ subunits, these findings suggest that this is where alcohol acts to suppress tremor. It is anticipated that medications designed specifically to target α6βδ-containing GABA_A receptors may be effective and well-tolerated for treating essential tremor.

Highlights

How does alcohol temporarily ameliorate essential tremor? This study with a mouse model found that two specific kinds of GABA receptor subunits were needed for alcohol to work. As receptors with both these subunits are found mainly in cerebellum, this work suggests this is where alcohol acts to suppress tremor.

Biochemical and molecular insights on the bioactivity and binding interactions of Bacillus australimaris NJB19 L-asparaginase

L-asparaginase, an antileukemic enzyme, is indispensable to the treatment of Acute Lymphoblastic Leukemia (ALL). However, the intrinsic glutaminase activity entails various side effects to the patients; thus, an improved version of the enzyme lacking glutaminase activity would be a requisite for effective treatment management of ALL. The present study highlights the biochemical and molecular characteristics of the recombinant glutaminase-free L-asparaginase from Bacillus australimaris NJB19 (BaAsp). Investigation of the active site architecture of the protein unraveled the binding interactions of BaAsp with its substrate. Comparative analysis of the L-asparaginase sequences revealed few substitutions of key amino acids in the BaAsp that could construe its substrate selectivity and specificity. The purified heterologously expressed protein (42 kDa) displayed maximum L-asparaginase activity at 35-40 °C and pH 8.5-9, with no observed L-glutaminase activity. The kinetic parameters, Km and Vmax, were determined as 45.6 μM and 0.16 μmoles min^-1, respectively. Furthermore, in silico analysis revealed a conserved zinc-binding site in the protein, which is generally implicated in inhibiting the L-asparaginase activity. However, BaAsp was not inhibited by zinc at 1 mM concentration. Therefore, the findings provide insights on the biochemical and molecular details of BaAsp, which could be valuable in formulating it for alternate antileukemic drug therapy.

Identification and Contribution of Inflammation-Induced Novel MicroRNA in the Pathogenesis of Systemic Lupus Erythematosus

Recently microRNAs (miRNAs) have been recognized as powerful regulators of many genes and pathways involved in the pathogenesis of inflammatory diseases including Systemic Lupus Erythematosus (SLE). SLE is an autoimmune disease characterized by production of various autoantibodies, inflammatory immune cells, and dysregulation of epigenetic changes. Several candidate miRNAs regulating inflammation and autoimmunity in SLE are described. In this study, we found significant increases in the expression of miR21, miR25, and miR186 in peripheral blood mononuclear cells (PBMCs) of SLE patients compared to healthy controls. However, miR146a was significantly decreased in SLE patients compared to healthy controls and was negatively correlated with plasma estradiol levels and with SLE disease activity scores (SLEDAI). We also found that protein levels of IL-12 and IL-21 were significantly increased in SLE patients as compared to healthy controls. Further, our data shows that protein levels of IL-12 were positively correlated with miR21 expression and protein levels of IL-21 positively correlated with miR25 and miR186 expression in SLE patients. In addition, we found that levels of miR21, miR25, and miR186 positively correlated with SLEDAI and miR146a was negatively correlated in SLE patients. Thus, our data shows a dynamic interplay between disease pathogenesis and miRNA expression. This study has translational potential and may identify novel therapeutic targets in patients with SLE.

Speckle-based deep learning approach for classification of orbital angular momentum modes

We present a speckle-based deep learning approach for orbital angular momentum (OAM) mode classification. In this method, we have simulated the speckle fields of the Laguerre-Gauss (LG), Hermite-Gauss (HG), and superposition modes by multiplying these modes with a random phase function and then taking the Fourier transform. The intensity images of these speckle fields are fed to a convolutional neural network (CNN) for training a classification model that classifies modes with an accuracy >99%. We have trained and tested our method against the influence of atmospheric turbulence by training the models with perturbed LG, HG, and superposition modes and found that models are still able to classify modes with an accuracy >98%. We have also trained and tested our model with experimental speckle images of LG modes generated by three different ground glasses. We have achieved a maximum accuracy of 96% for the most robust case, where the model is trained with all simulated and experimental data. The novelty of the technique is that one can do the mode classification just by using a small portion of the speckle fields because speckle grains contain the information about the original mode, thus eliminating the need for capturing the whole modal field, which is modal dependent.

A novel process driving Alzheimer's disease validated in a mouse model: Therapeutic potential

Introduction

The neuronal mechanism driving Alzheimer's disease (AD) is incompletely understood.

Methods

Immunohistochemistry, pharmacology, biochemistry, and behavioral testing are employed in two pathological contexts—AD and a transgenic mouse model—to investigate T14, a 14mer peptide, as a key signaling molecule in the neuropathology.

Results

T14 increases in AD brains as the disease progresses and is conspicuous in 5XFAD mice, where its immunoreactivity corresponds to that seen in AD: neurons immunoreactive for T14 in proximity to T14‐immunoreactive plaques. NBP14 is a cyclized version of T14, which dose‐dependently displaces binding of its linear counterpart to alpha‐7 nicotinic receptors in AD brains. In 5XFAD mice, intranasal NBP14 for 14 weeks decreases brain amyloid and restores novel object recognition to that in wild‐types.

Discussion

These findings indicate that the T14 system, for which the signaling pathway is described here, contributes to the neuropathological process and that NBP14 warrants consideration for its therapeutic potential.

Cellular and Molecular Phenotypes of pConsensus Peptide (pCons) Induced CD8+ and CD4+ Regulatory T Cells in Lupus

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease with widespread inflammation, immune dysregulation, and is associated with the generation of destructive anti-DNA autoantibodies. We have shown previously the immune modulatory properties of pCons peptide in the induction of both CD4⁺ and CD8⁺ regulatory T cells which can in turn suppress development of the autoimmune disease in (NZB/NZW) F1 (BWF1) mice, an established model of lupus. In the present study, we add novel protein information and further demonstrate the molecular and cellular phenotypes of pCons-induced CD4⁺ and CD8⁺ T_reg subsets. Flow cytometry analyses revealed that pCons induced CD8⁺ T_reg cells with the following cell surface molecules: CD25^highCD28^{high and low} subsets (shown earlier), CD62L^high, CD122^low, PD1^low, CTLA4^low, CCR7^low and 41BB^high. Quantitative real-time PCR (qRT-PCR) gene expression analyses revealed that pCons-induced CD8⁺ T_reg cells downregulated the following several genes: Regulator of G protein signaling (RGS2), RGS16, RGS17, BAX, GPT2, PDE3b, GADD45β and programmed cell death 1 (PD1). Further, we confirmed the down regulation of these genes by Western blot analyses at the protein level. To our translational significance, we showed herein that pCons significantly increased the percentage of CD8⁺FoxP3⁺ T cells and further increased the mean fluorescence intensity (MFI) of FoxP3 when healthy peripheral blood mononuclear cells (PBMCs) are treated with pCons (10 μg/ml, for 24-48 hours). In addition, we found that pCons reduced apoptosis in CD4⁺ and CD8⁺ T cells and B220⁺ B cells of BWF1 lupus mice. These data suggest that pCons stimulates cellular, immunological, and molecular changes in regulatory T cells which in turn protect against SLE autoimmunity.

Interferon Genes Are Influenced by 17β-Estradiol in SLE

Recent evidence suggests the existence of a nexus between inflammatory pathways and the female sex hormone 17β-estradiol, resulting in increased interferon-stimulated genes (ISGs), autoantibodies, and dysregulation of immune cells in SLE. However, the molecular mechanisms and the effect of estradiol on candidate target genes and their pathways remains poorly understood. Our previous work suggests that female SLE patients have increased estradiol levels compared to healthy controls. In the present study, we explored the effects of 17β-estradiol treatment on expression of IFN (interferons)-stimulated genes and pro-inflammatory cytokines/chemokines. We found significantly increased (5-10-fold) expression of IFN-regulated genes in healthy females. Furthermore, we found significantly increased plasma levels of IL-6, IL-12, IL-17, IL-18, stem cell factor (SCF), and IL-21/IL-23 in SLE patients compared to healthy controls, and those levels positively correlated with the plasma levels of 17β-estradiol. In addition, levels of IL-21 positively correlated with the SLE disease activity index (SLEDAI) score of SLE patients. In vitro treatment of PBMCs from either SLE patients or healthy controls with 17β-estradiol at physiological concentration (~50 pg/ml) also significantly increased secretion of many pro-inflammatory cytokines and chemokines (IL-6, IL-12, IL-17, IL-8, IFN-γ; MIP1α, and MIP1β) in both groups. Further our data revealed that 17β-estradiol significantly increased the percentage of CD3⁺CD69⁺ and CD3⁺IFNγ⁺ T cells; whereas, simultaneous addition of 17β-estradiol and an ERα inhibitor prevented this effect. Collectively, our findings indicate that 17β-estradiol participates in the induction of pro-inflammatory cytokines and chemokines and further influences interferon genes and pathways.

CD8+ T regulatory cells in lupus

T regulatory cells (T_regs) have a key role in the maintenance of immune homeostasis and the regulation of immune tolerance by preventing the inflammation and suppressing the autoimmune responses. Numerical and functional deficits of these cells have been reported in systemic lupus erythematosus (SLE) patients and mouse models of SLE, where their imbalance and dysregulated activities have been reported to significantly influence the disease pathogenesis, progression and outcomes. Most studies in SLE have focused on CD4⁺ T_regs and it has become clear that a critical role in the control of immune tolerance after the breakdown of self-tolerance is provided by CD8⁺ T_regs. Here we review the role, cellular and molecular phenotypes, and mechanisms of action of CD8⁺ T_regs in SLE, including ways to induce these cells for immunotherapeutic modulation in SLE.

Outcomes of free flap reconstructive surgery in head and neck cancer patients over 80-years old

An increasing elderly population in the United Kingdom has led to an increasing number of older patients with head and neck cancer, resulting in a greater demand for complex head and neck reconstructive surgery in this potentially high-risk age group. A possible perceived poorer tolerance to such major treatment risks under-treating some of these patients. The purpose of this study was to assess the outcomes in the elderly population (older than 80 years) who had undergone free flap reconstruction following head and neck cancer resection. A retrospective review of 127 patients was performed. Eighteen patients were 80 or older (14.2%) and 109 under 80 (85.8%). The elderly group experienced increased number of postoperative medical complications (p=0.01), but the surgical complications were not significantly different in the two groups (p=0.4). The average length of hospital stay was significantly longer in the older group (p=0.01). There was one flap failure during the study period, which belonged to the younger group of patients. Elderly patients undergoing free flap reconstruction experience an increased rate of postoperative medical complications resulting in an increased length of hospital stay. However, good surgical outcomes can still be achieved in this age group, and therefore age alone should not be considered as a primary factor in head and neck cancer management.

Effects of Peptide-Induced Immune Tolerance on Murine Lupus

The regulation of autoimmunity and the molecular mechanisms by which different immune cells, including T cells, polymorphonuclear leukocytes (PMN-granulocytes), and B cells suppress autoimmune diseases is complex. We have shown previously that BWF1 lupus mice are protected from autoimmunity after i.v. injection or oral administration of tolerogenic doses of pCons, an artificial synthetic peptide based on sequences containing MHC class I and MHC class II determinants in the VH region of a J558-encoded BWF1 anti-DNA Ab. Several T cell subsets can transfer this tolerance. In this study, we determined the potential roles of granulocytes, B cells and regulatory T cells altered by pCons treatment in the BWF1 (NZB/NZW) mouse model of lupus. Immunophenotyping studies indicated that pCons treatment of BWF1 mice significantly increased CD4⁺FoxP3⁺ T cells, reduced the percent of B cells expressing CD19⁺CD5⁺ but increased the percent of CD19⁺CD1d⁺ regulatory B cells and increased the ability of the whole B cell population to suppress IgG anti-DNA production in vitro. pCons treatment significantly decreased the expression of CTLA-4 (cytotoxic T-lymphocyte-associated protein-4) in CD8⁺ T cells. In addition, peptide administration modified granulocytes so they became suppressive. We co-cultured sorted naïve B cells from mice making anti-DNA Ab (supported by addition of sorted naive CD4⁺ and CD8⁺ T cells from young auto-antibody-negative BWF1 mice) with sorted B cells or granulocytes from tolerized mice. Both tolerized granulocytes and tolerized B cells significantly suppressed the production of anti-DNA in vitro. In granulocytes from tolerized mice compared to saline-treated littermate controls, real-time PCR analysis indicated that expression of interferon-induced TNFAIP2 increased more than 2-fold while Ptdss2 and GATA1 mRNA were up-regulated more than 10-fold. In contrast, expression of these genes was significantly down-regulated in tolerized B cells. Further, another IFN-induced protein, Bcl2, was reduced in tolerized B cells as determined by Western blot analyses. In contrast, expression of FoxP3 was significantly increased in tolerized B cells. Together, these data suggest that B cells and granulocytes are altered toward suppressive functions by in vivo tolerization of BWF1 mice with pCons and it is possible these cell types participate in the clinical benefits seen in vivo.

Sex Hormones and Gender Influence the Expression of Markers of Regulatory T Cells in SLE Patients

Regulatory T cells have been implicated in the regulation and maintenance of immune homeostasis. Whether gender and sex hormones differentially influence the expression and function of regulatory T cell phenotype and their influence on FoxP3 expression remains obscure. We provide evidence in this study that the number and percent of human regulatory T cells (T_regs) expressing CD4⁺ and CD8⁺ are significantly reduced in healthy females compared to healthy males. In addition, both CD4⁺CD25^+hi and CD8⁺CD25^+hi subsets in healthy males have a 2-3 fold increase in FoxP3 mRNA expression compared to healthy females. Female SLE patients, compared to healthy women, have elevated plasma levels of estradiol and decreased levels of testosterone. Higher levels of testosterone correlate with higher expression of FoxP3 in CD4⁺CD25^hiCD127^low putative T_regs in women with SLE. Incubation of CD4⁺ regulatory T cells with 17β-estradiol at physiological levels generally decreased FoxP3 expression in females with SLE. These data suggest that females may be more susceptible than males to SLE and other autoimmune diseases in part because they have fewer T_regs and reduced FoxP3 expression within those cells due to normal E2 levels which suppress FoxP3 expression. In addition, low levels of plasma testosterone in women may further reduce the ability of the T_regs to express FoxP3. These data suggest that gender and sex hormones can influence susceptibility to SLE via effects on regulatory T cells and FoxP3 expression.

Bradyrhizobium arachidis mediated enhancement of (oxy)matrine content in the medicinal legume Sophora flavescens

Effect of rhizobial inoculation and nitrate application on the content of bioactive compounds in legume plants is an interesting aspect for interactions among microbes, plants and chemical fertilizers, as well as for cultivated practice of legumes. In this study, nitrate (0, 5 and 20 mmol l^-1 ) and Bradyrhizobium arachidis strain CCBAU 051107^T were applied, individually or in combination, to the root rhizosphere of the medicinal legume Sophora flavescens Aiton (SFA). Then the plant growth, nodulation and active ingredients including (oxy)matrine of SFA were determined and compared. Rhizobial inoculation alone significantly increased the numbers and fresh weight of root nodules. Nodulation was significantly inhibited due to nitrate (5 and 20 mmol l^-1 ). Only oxymatrine was detected in the control plants without rhizobial inoculation and nitrate supplement, while both oxymatrine and matrine were synthesized in plants treated with inoculation of B. arachidis or supplied with nitrate. The content of oxymatrine was the highest in plants inoculated solely with rhizobia and was not significantly altered by additional application of nitrate. Combinations of B. arachidis inoculation and different concentrations of nitrate did not significantly change the concentrations of (oxy)matrine in the plant. In conclusion, sole rhizobial inoculation was the best approach to increase the contents of key active ingredients oxymatrine and matrine in the medicinal legume SFA.

Emergent superconductivity by Re doping in type -II Weyl semimetal NiTe2

Recently topological semimetals emerge as a new platform to realise topological superconductivity. Here we report the emergent superconductivity in single-crystals of Re doped type-II Weyl semimetal NiTe₂. The magnetic and transport measurements highlight that Re substitution in Ni-site induces superconductivity at a maximum temperature of 2.36 K. Hall effect and specific heat measurements indicate that Re substitution is doping hole and facilitates the emergence of superconductivity by phonon softening and enhancing the electron-phonon coupling.

A potential type-II L-asparaginase from marine isolate Bacillus australimaris NJB19: Statistical optimization, in silico analysis and structural modeling

L-asparaginase is a cardinal biotherapeutic drug for treating acute lymphoblastic leukemia, which is highly prevalent in children worldwide. In the current investigation, L-asparaginase producing marine bacterial isolate, Bacillus australimaris NJB19 (MG734654), was observed to be producing extracellular glutaminase free L-asparaginase (13.27 ± 0.4 IU mL^-1). Production of L-asparaginase was enhanced by the Box-Behnken design approach that enumerated the significant variables affecting the enzyme production. The optimum levels of the derived variables resulted in 2.8-fold higher levels of the enzyme production (37.93 ± 1.06 IU mL^-1). An 1146 bp L-asparaginase biosynthetic gene of Bacillus australimaris NJB19 was identified and cloned in E. coli DH5α, fused with a histidine tag. The in silico analysis of the protein sequence revealed the presence of a signal peptide and classified it as a type II L-asparaginase. Toxic peptide prediction disclosed no toxin domain in the protein sequence, hence suggesting it as a non-toxic protein. The secondary structure analysis of the enzyme displayed a comparable percentage of alpha-helical and random coil structure, while 14.39% and 6.57% of amino acid residues were composed of extended strands and beta-turns, respectively. The functional sites in the three-dimensional structural model of the protein were predicted and interestingly had a few less conserved residues. Bacillus australimaris NJB19 identified in this study produces type-II L-asparaginase, known for its high affinity for asparagine and effectiveness against leukemic cells. Hence, these observations indicate the L-asparaginase, thus obtained, as a potentially significant and novel therapeutic drug.

CCL21-DC tumor antigen vaccine augments anti-PD-1 therapy in lung cancer

<abstract> <p>Targeting inhibitory immune checkpoint molecules has highlighted the need to find approaches enabling the induction and activation of an immune response against cancer. Therapeutic vaccination, which can induce a specific immune response against tumor antigens, is an important approach to consider. Although this approach has shown low clinical efficacy when combined with other treatment modalities, therapeutic cancer vaccines will have a better outcome when combined with immune checkpoint blockade therapy with potential for cancer free survival. In this review, we will discuss the results of our two recent publications in preclinical lung cancer models. Our studies reveal that anti-PD-1 administered in combination with CCL21-DC tumor antigen therapeutic vaccines eradicate lung cancer. The results of these studies highlight the importance of combination therapy of immune checkpoint blockade and therapeutic cancer vaccines for lung cancer patients.</p> </abstract>

Comparison of provision of maxillofacial emergency service during the two COVID-19 national lockdowns in the United Kingdom

We previously published a study on the provision of emergency maxillofacial services during the first UK COVID-19 pandemic national lockdown. We repeated the study during the second lockdown and now present our findings that highlight the main differences and learning issues as the services have evolved.

3-D macro/microporous-nanofibrous bacterial cellulose scaffolds seeded with BMP-2 preconditioned mesenchymal stem cells exhibit remarkable potential for bone tissue engineering

Bone repair using BMP-2 is a promising therapeutic approach in clinical practices, however, high dosages required to be effective pose issues of cost and safety. The present study explores the potential of low dose BMP-2 treatment via tissue engineering approach, which amalgamates 3-D macro/microporous-nanofibrous bacterial cellulose (mNBC) scaffolds and low dose BMP-2 primed murine mesenchymal stem cells (C3H10T1/2 cells). Initial studies on cell-scaffold interaction using unprimed C3H10T1/2 cells confirmed that scaffolds provided a propitious environment for cell adhesion, growth, and infiltration, owing to its ECM-mimicking nano-micro-macro architecture. Osteogenic studies were conducted by preconditioning the cells with 50 ng/mL BMP-2 for 15 min, followed by culturing on mNBC scaffolds for up to three weeks. The results showed an early onset and significantly enhanced bone matrix secretion and maturation in the scaffolds seeded with BMP-2 primed cells compared to the unprimed ones. Moreover, mNBC scaffolds alone were able to facilitate the mineralization of cells to some extent. These findings suggest that, with the aid of 'osteoinduction' from low dose BMP-2 priming of stem cells and 'osteoconduction' from nano-macro/micro topography of mNBC scaffolds, a cost-effective bone tissue engineering strategy can be designed for quick and excellent in vivo osseointegration.

Determination of Stark Shifts and Widths Using Time Resolved Laser-Induced Breakdown Spectroscopy (LIBS) Measurements

Stark broadening parameters have been estimated for resonant lines of Al(I) using time resolved measurements. The relation between the various emission line characteristics at different phases of opacity have been utilized to obtain the value of plasma temperature and Stark width parameters from the experimental data. The observed value of the center line intensity and Lorentzian component of the line width are compared against a simulated value of these parameters for optically thin case. The plasma temperature and Stark broadening parameters are obtained for the best fit condition by matching the experimentally observed and the simulated values of intensity and line widths. The time resolved measurements result in much better estimates for Stark parameters by allowing multiple points for fitting keeping the number of variables limited. The Stark shift parameters are also obtained from the slope of the plot of observed central wavelength shifts versus observed electron number density which is measured as a function of time. Hence, a method utilizing multiple-time observation data to obtain the Stark broadening parameters for lines showing self-absorption has been demonstrated.

Provision of Emergency Maxillofacial Service During the COVID-19 Pandemic : A Collaborative Five Centre UK Study

The global pandemic of Coronavirus disease (COVID-19) represents one of the greatest challenges to healthcare systems, and has forced medical specialties to rapidly adapt their approaches to patient care. Oral and Maxillofacial Surgery is considered particularly at risk of disease transmission due to aerosol generation during surgical interventions, patient proximity and operating environment. On day 2 (26th March, 2020) of when severe restrictions in population movement were instigated in the United Kingdom, we began a study to prospectively monitor the presentation and management of maxillofacial emergencies at five hospital trusts. Data was collected onto an online live database fed through a smartphone application. Of the total 529 patients over six weeks, 395 attended for face-to-face consultations and 134 patients received remote consultations via telephone or video link. There were 255 trauma related cases, 221 infection and 48 cases of postoperative complications. Most trauma cases were minor soft tissue injury related to slip, trip or fall at home. There were 44 cases of facial fractures with a tendency for conservative treatment. 19 cases were related to domestic violence or self-harm. Of the 216 dental related emergencies, 68% could have been managed in the primary care setting. A quarter of all emergency patients were satisfactorily managed by remote consultations. There was a significant change in the provision of emergency maxillofacial service during the pandemic lockdown. We discuss the study findings as well as the potential implications in relation to planning for possible further COVID- 19 spikes and future pandemics.

P1342OUTCOME OF ELDERLY PATIENTS AFTER PREDIALYSIS VASCULAR ACCESS CREATION

Background and Aims

Guidelines to create vascular access for elderly patients is guided by a number of factors i.e. competing risk of death, high rate of arteriovenous fistula (AVF) maturation failure, and poor vascular access outcomes, influencing the outcomes in this population . Does early creation of AVF in elderly patients with advanced CKD influence dialysis outcomes needs evaluation.

Method

We conducted a retrospective study among elderly (&gt; 65 years ) who chose to create a permanent vascular access before dialysis initiation were identified between Jan 2014-Jan 2017 in Tertiary care hospital, Lucknow and assessed in 43 elderly patients (aged ≥65 years) with CKD undergoing predialysis AVF .

Results

They were observed for the frequencies of dialysis initiation, death before dialysis initiation, and dialysis-free survival for 2 years after vascular access creation. 45.6 % were diabetic, 78.9% were hypertensive, and 14.2 % had peripheral vascular disease. In all, 67% of patients with predialysis AVF initiated dialysis within 1 years of access placement, but the overall risk of dialysis initiation was modified by patient age. Only one half of patients initiated dialysis with a functioning AVF, 47.9% of AVFs were created &lt;90 days before dialysis initiation. The primary patency rates were 42.7% at one year and 37.8 % at 2 years. Catheter dependence at dialysis initiation was more common in patients receiving predialysis AVF. In conclusion, most elderly patients with advanced CKD who received predialysis vascular access creation initiated dialysis within 1 year. As a consequence of late predialysis placement or maturation failure, almost one half of patients receiving AVFs initiated dialysis with a catheter.

Conclusion

Insertion of an AVF closer to dialysis initiation may serve as a “catheter-sparing” approach and allow delay of permanent access placement in selected elderly patients with CKD.

P1048EMPHYSEMATOUS PYELONEPHRITIS IN TYPE 2 DIABETES -CLINICAL PROFILE AND MANAGEMENT

Background and Aims

Emphysematous pyelonephritis (EPN) is a rare but life-threatening acute suppurative infection of the kidney.60-70% are associated with uncontrolled diabetes mellitus (DM) with or without obstructive uropathy and superimposed with infection caused by gas-forming organisms. Conventional treatment of EPN is parenteral antibiotics with percutaneous or open surgical drainage and/or nephrectomy. There is no current consensus on management of EPN as to whether present day antibiotics alone good enough or is surgical intervention necessary and if surgical intervention required when should one go for nephrectomy.

Method

A prospective observational study was conducted at Tertiary care hospital, Lucknow from 2015-2018 to look for clinical, microbial profile and treatment outcome of diabetic patients with emphysematous pyelonephritis.The clinical features and laboratory data at the initial presentation, management and outcomes were analyzed .Contrast enhanced computerized tomography (CECT) was performed in case of suspected renal abscess and nonrecovering pyelonephritis

Results

A total of 76 Diabetic patients diagnosed with pyelonephritis were identified, of which 15 patients were diagnosed with EPN (26.3%) Renal papillary necrosis and renal abscess was seen in 1 and 3 patients, respectively. The mean age of the patients was 58.4 ± 6.5 years (age range 22-79 years). Pyelonephritis was more common among males. Duration of symptoms prior to hospitalization ranged from 16.34 ± 7.32 (range 8-32) days. Renal dysfunction at presentation was seen in 15 (100%) patients. Bilateral involvement was seen in 5 (33.3%) patients. Fever was the most common presenting symptom followed by dysuria. Urine and blood cultures were positive in 13 (88.3%) and 3 (20 %) patients respectively. Gram-negative bacilli were the most frequent organisms isolated, Escherichia coli in 11 (73.3%), Klebsiella sp. in 1 (6.6%), Pseudomonas in 1 (6.6%), and 1 each with polymicrobial and fungal UTI respectively. The fungus included Candida albicans managed with fluconazole. Good, moderate, and poor glycemic control was seen in 13 (12.3%), 16 (15.2%) and 76 (72.3%), respectively.Of 15 EPN patients, 13 (86.6 %) survived and 2 (13.3%) expired. 2 of them underwent Nephrectomy both survived.All patients with Stage I, II and IIIa EPN (n = 12) were managed with antibiotics with or without PCD. In EPN Stage IIIb/IV (n = 3), all the 3 (20 %) patients were managed with antibiotics and PCD and later 2 (13.3%) needed nephrectomy.Of different variable only altered sensorium and shock at presentation were associated with poor outcome in EPN patients (P &lt; 0.05)

Conclusion

EPN in diabetics needs good multidisciplinary approach with adequate antibiotics and surgical management as and well required for better patient outcomes.

Optical-vortex diagnostics via Fraunhofer slit diffraction with controllable wavefront curvature

Far-field slit diffraction of circular optical-vortex (OV) beams is efficient for measurement of the topological charge (TC) magnitude but does not reveal its sign. We show that this is because in the common diffraction schemes the diffraction plane coincides with the incident OV waist plane. Based on the examples of Laguerre-Gaussian incident beams containing a spherical wavefront component, we demonstrate that the far-field diffracted beam profile possesses an asymmetry depending on the incident wavefront curvature and the TC sign. This finding enables simple and efficient ways for the simultaneous diagnostics of the TC magnitude and sign, which can be useful in many OV applications, including OV-assisted metrology and information processing.

Correction: Photocatalytic antibacterial performance of TiO2 and Ag-doped TiO2 against S. aureus. P. aeruginosa and E. coli

[This corrects the article DOI: 10.3762/bjnano.4.40.].

Influence of Metabolic Status and Diet on Early Pregnant Equine Histotroph Proteome: Preliminary Findings

Insulin resistance (IR) is characterized by an increase in biomarkers of systemic inflammation and susceptibility to laminitis in horses. Impacts on reproduction include a lengthened interovulatory period in horses. Dietary omega-3 (docosahexaenoic acid [DHA]) promotes anti-inflammatory processes, has been implicated in health benefits, and can reduce cytokine secretion. This preliminary study investigated the impact of IR as well as the influence of dietary supplementation (DHA) on the uterine fluid proteome in early pregnant horses. Mares were artificially inseminated; uterine fluid and embryos were collected on d 12.5 after ovulation. Uterine fluid was pooled for metabolic and diet categories (n = 8; n = 2 per metabolic and dietary status) and concentrated, and the proteome was analyzed using tandem mass spectrometry (iTRAQ). Five proteins met differential abundance criteria (±1.5-fold change, P < .05) in all comparisons (Control C, IS vs. C, IR; C, IS vs. DHA, IS; C, IR vs. DHA, IR). Serum amyloid A, afamin, and serotransferrin were upregulated in C, IR mares but downregulated in DHA, IR mares when compared to C, IS and C, IR, respectively. Quantitative PCR supported mass spectrometry results. The presence of serum amyloid A and serotransferrin in histotroph of IR mares potentially indicates an inflammatory response not seen in IS counterparts. These preliminary findings provide novel evidence on the potential impact of insulin resistance and DHA supplementation on the secreted equine uterine proteome during early pregnancy.

Nodeless s-wave superconductivity in the [Formula: see text]-Mn structure type noncentrosymmetric superconductor TaOs: a [Formula: see text]SR study

Noncentrosymmetric superconductors can lead to a variety of exotic properties in the superconducting state such as line nodes, multigap behavior, and time-reversal symmetry breaking. In this paper, we report the properties of a new noncentrosymmetric superconductor TaOs, using muon spin relaxation and rotation measurements. It is shown using the zero-field muon experiment that TaOs preserve the time-reversal symmetry in the superconducting state. From the transverse field muon measurements, we extract the temperature dependence of [Formula: see text], which is proportional to the superfluid density. This data can be fit with a fully gapped s-wave model for [Formula: see text]  =  2.01 [Formula: see text] 0.02. Furthermore, the value of magnetic penetration depth is found to be 5919 [Formula: see text] 45 [Formula: see text], which is consistent with the value obtained from the bulk measurements.

P41 Correlation of doppler ultrasound assessment of carotid femoral pulse wave velocity with coronary artery disease

Funding Acknowledgements

self

Background

Arterial stiffness is an important cardiovascular risk factor. Carotid femoral pulse wave velocity (cfPWV) is simple noninvasive  method to determine aortic stiffness. Arterial stiffness measures, cfPWV in particular,  have been found to be correlate with stroke and peripheral artery disease. Usually SphygmoCor or Complior are used to calculate cfPWV. Doppler ultrasound can serve as an alternative to these methods. 

Purpose

To assess cfPWV using doppler ultrasound and study its correlation with coronary artery disease and its severity. 

Methods

cfPWV was assessed by ultrasound Doppler in patient aged 20-70 years undergoing coronary angiography.  cfPWV was measured by sequential recordings of arterial pressure waveform at the carotid and femoral arteries with a Doppler ultrasound with ECG gating and calculated as the distance between the carotid and the femoral sampling site divided by the time interval. 

Result

Of the 358 subjects studied, 243 had coronary artery disease(CAD) (&gt;50% diameter stenosis) and were further divided into single, double or triple vessel disease groups. 115 patients  had mild CAD (&lt; 50% stenosis) or no CAD and served as controls. Baseline characteristics were similar except diabetes (more common in CAD group)(39.09% v/s 27.82%). cfPWV was found to increase with age in all groups. cfPWV was not significantly affected  by sex, diabetes, dyslipidemia, BMI, smoking or hypothyroidism. Mean cfPWV was significantly higher in patients with CAD (8.99 v/s 6.51 m/s, p &lt; 0.001) and hypertensives (8.71 v/s 7.83 m/s, p &lt; 0.001). Patients with triple vessel disease(TVD) had significantly higher cfPWV (10.12 m/s) than those with double(DVD)(8.84 m/s) or single vessel disease(SVD)(8.28m/s)(p &lt; 0.001). Multinomial logistic regression revealed an odds ratio of 2.00, 2.375 and 3.368 respectively for SVD, DVD and TVD groups in comparison to controls (p &lt; 0.001). cfPWV value &gt; 7.25 m/s predicted CAD with sensitivity 78.6 % and specificity 74.8% (AUC =0.848, P &lt; 0.001). 

Conclusion

Carotid femoral pulse wave velocity can be measured noninvasively by ultrasound Doppler. cfPWV increases with age and hypertension and has strong correlation with coronary artery disease and its severity. The cfPWV can be an independent risk factor and may be utilized for cardiovascular risk prediction.

Abstract P41 Figure. cfPWV in various subgroups.

Observing sub-Poissonian statistics of twisted single photons using oscilloscope

Heralded single photon sources (HSPSs) from spontaneous parametric down-conversion are widely used as single photon sources. We study the photon number statistics of an HSPS carrying orbital angular momentum in our laboratory and observe the sub-Poissonian statistics using only photodetectors and an oscilloscope.

Tunable ultraviolet vortex source based on a continuous-wave optical parametric oscillator

We report a continuous-wave (cw) optical parametric oscillator (OPO) generating optical vortices tunable in the ultraviolet (UV). Based on MgO:sPPLT as the nonlinear crystal, the singly resonant OPO is pumped by a cw vortex beam in the green, and deploying intracavity sum-frequency generation (SFG) between the undepleted pump and the Gaussian resonant signal in the crystal of BiB₃O₆, it can generate optical vortices of order, l_uv=1 and 2, tunable across 332-344 nm in the UV with a maximum power of 12 mW. Due to conservation of orbital angular momentum in the parametric process, the OPO also produces a non-resonant idler output beam in a vortex spatial profile of order l_i=1 and 2, identical to the pump vortex, with the signal beam in Gaussian distribution. The idler vortex is tunable across 1172-1338 nm with maximum output power of 1.3 W.

Expression and characterization of the non-structural protein V of small ruminant morbillivirus

Peste-des-petits ruminants is a transboundary viral disease of small ruminants caused by small ruminant morbillivirus (SRMV). In the present study, the full-length V gene of SRMV was constructed through site-directed mutagenesis from the P gene transcripts of the vaccine virus (Sungri/96 India) and expressed in a prokaryotic expression system. In animals, the seroconversion against this protein occurs from 14-days and is getting produced from 48 h in cell culture. An indirect ELISA developed using this protein has a relative sensitivity and relative specificity of 77.73% and 73.775%, respectively as compared to c-ELISA. In this ELISA, it was observed that most of the convalescent animals elicited higher level of antibodies than vaccinated animals.

Phylogenetic analysis of haemagglutinin gene deciphering a new genetically distinct lineage of canine distemper virus circulating among domestic dogs in India

Canine distemper (CD) is one of the highly contagious and invariably fatal viral diseases of dogs and other carnivores. Despite the widespread use of modified live vaccines to control CD, the prevalence of disease has increased at an alarming rate in recent years. Although a number of factors may be ascribed for vaccine failure, antigenic differences among the vaccine and wild-type strains have gained the interest of researchers. Considering the high genetic variability of haemagglutinin gene (H gene) and its role in eliciting the immune response to canine distemper virus (CDV), we have generated nine full-length CDV H gene sequences from infected dogs including three vaccinated cases. Bayesian analysis was performed using 102 full-length H gene nucleotide sequences over a time frame of 76 years (1940-2016) from 18 countries. The time to the most recent common ancestor (tMRCA) of CDV was estimated to be 1696 AD. Phylogenetic reconstruction clustered Indian wild-type viruses into a distinct monophyletic group clearly separated from the previously established CDV lineages. This signifies the presence of a novel genetic variant (proposed as "Lineage India-1/Asia-5") circulating among dog population in India. To investigate the importance of substitutions at amino acid residues 530 and 549 of CDV H protein in determining the host switches from canid to non-canid hosts, we analysed 125 H gene sequences including nine sequences generated in this study. Selection pressure analysis and analysis of amino acid sequences revealed a trend towards adaptation of 549H variants in non-canid hosts although no role of G/E530R/D/N substitution could be identified. This is the first comprehensive study about the nature and ecology of CDV circulating among dog population in India. Outbreaks in vaccinated animals as observed in this study have raised a concern towards the effectiveness of current vaccine strains warranting detailed investigation.

Point contact Andreev reflection studies of a non-centro symmetric superconductor Re6Zr

Re₆Zr, a non-centrosymmetric superconductor is an interesting system as recent experimental evidence suggests that the superconducting state breaks time reversal symmetry. This implies a mixing of spin singlet-triplet states leading to a complex order parameter in this system. Here, we report point contact Andreev Reflection (PCAR) measurements on a single crystal of Re₆Zr (superconducting transition temperature (T_c) = 6.78 K). We observe multiple gap features in the PCAR spectra which depends on the type of tip and contact. Spectral features appear at voltages 1.0 ± 0.1 mV, 0.75 ± 0.05 mV and 0.45 ± 0.1 mV suggesting that there are at least more than one band contributing to superconductivity. However, strong surface inter-band scattering is possibly responsible for the uncertainty in observing them together distinctly in a single contact in the PCAR measurements. Interestingly, the bulk gap (Δ  = 1.95k_BT_c = 1.1 meV) is occasionally observed in PCAR spectra, mostly with ferromagnetic tips. The gap features associated with the other two smaller gaps disappear at the bulk T_c. In addition, no anisotropy in the upper critical field was observed. Our results suggest an unconventional superconducting order in this compound: Multiband singlet states dominated by inter-band pairing which break the time reversal symmetry or singlet mixed with triplet states.

Time-Reversal Symmetry Breaking in Re-Based Superconductors

To trace the origin of time-reversal symmetry breaking (TRSB) in Re-based superconductors, we performed comparative muon-spin rotation and relaxation (μSR) studies of superconducting noncentrosymmetric Re_{0.82}Nb_{0.18} (T_{c}=8.8  K) and centrosymmetric Re (T_{c}=2.7  K). In Re_{0.82}Nb_{0.18}, the low-temperature superfluid density and the electronic specific heat evidence a fully gapped superconducting state, whose enhanced gap magnitude and specific-heat discontinuity suggest a moderately strong electron-phonon coupling. In both Re_{0.82}Nb_{0.18} and pure Re, the spontaneous magnetic fields revealed by zero-field μSR below T_{c} indicate time-reversal symmetry breaking and thus unconventional superconductivity. The concomitant occurrence of TRSB in centrosymmetric Re and noncentrosymmetric ReT (T=transition metal), yet its preservation in the isostructural noncentrosymmetric superconductors Mg_{10}Ir_{19}B_{16} and Nb_{0.5}Os_{0.5}, strongly suggests that the local electronic structure of Re is crucial for understanding the TRSB superconducting state in Re and ReT. We discuss the superconducting order parameter symmetries that are compatible with the experimental observations.

Grape berry surface bacterial microbiome: impact from the varieties and clones in the same vineyard from central China

AIMS

Bacterial microbiome on grape berry surface may play an important role in grape quality and health. This study aims to investigate the impact of grape varieties and clones on grape berry surface bacterial microbiome from the same vineyard.

METHODS AND RESULTS

High-throughput sequencing strategy was used to investigate the bacterial diversity and abundance on the grape surfaces of 12 clones belonging to six varieties grown in the same vineyard of Zhengzhou Fruit Research Institute in Henan Province. In total, 45 bacterial phyla and 933 genera were detected from all samples. Cyanobacteria, Proteobacteria and Firmicutes were the most abundant and prevalent phyla, while Bacteroidetes, Chloroflexi, Acidobacteria and Planctomycetes were grape clone specific phyla. The nonrank genus from phylum Cyanobacteria occupied 30-81% of grape clones from Italian Riesling (GRX), Cabernet Franc (PLZ), Pinot Blanc (BBN) and Riesling (LSL). Interestingly, Bacillus, Pseudomonas and Lactococcus were the only three prevalent genera found on all the clones. Furthermore, the predicted functional activities of grape surface bacterial communities varied according to the clones.

CONCLUSIONS

The present study revealed that in addition to the grape varieties, the variations in grape clone background may also affect the bacterial microbiome on grape surfaces which may ultimately determine their functional activities.

SIGNIFICANCE AND IMPACT OF THE STUDY

This research provides an important information for grape planting and wine fermentation that not only the grape varieties need to be paid attention but also grape clones from the specific variety need to be concerned.

Rhizobial biogeography and inoculation application to soybean in four regions across China

AIMS

The aim of the study was to survey rhizobial biogeography and to inoculate soybean with selected rhizobia in China to enhance symbiotic nitrogen fixation (SNF).

METHODS AND RESULTS

Biogeography, genetic diversity and phylogeny of soybean rhizobia were surveyed. Inocula were prepared and applied to soybean. Results showed that Bradyrhizobium elkanii and Ensifer fredii were widely distributed in acid and alkaline soils respectively. Available iron was detected as the first determinant for distribution of the two rhizobia and the soybean varieties did not greatly affect the rhizobial compatibility. Geographical latitude and precipitation in June were the main geographical and climatic factors affecting the rhizobial distribution. Inoculation with selected rhizobia increased the nodule number, fresh weight, occupation ratio, seed protein content and soybean yields.

CONCLUSIONS

Selection and application of effective soybean rhizobia across China according to biogeography were clarified to promote the SNF, thereby improving soybean yield.

SIGNIFICANCE AND IMPACT OF THE STUDY

Rhizobial diversity and biogeography were evaluated systematically in six sites across China. Available iron and soil pH are found to be the most important determinants for the distribution of soybean rhizobia. Inoculation to soybean enhances SNF, positively correlating to the increase in soybean yield and seed protein content.

Rapid visual isothermal nucleic acid-based detection assay of Brucella species by polymerase spiral reaction

AIM

The aim of this study was to develop polymerase spiral reaction (PSR) for rapid, sensitive and specific detection of Brucella sp.

METHODS AND RESULTS

Polymerase spiral reaction assay was developed using specifically designed primers targeting the conserved multicopy IS711 gene of Brucella sp. The assay could be performed within 60 min at an isothermal temperature of 64°C. The lower limit of detection of PSR was 11·8 fg and conventional PCR was 1·18 pg of Brucella abortus genomic DNA. Thus, PSR was found to be 100-fold more sensitive than conventional PCR and was comparable to real-time PCR. The specificity of PSR was tested with other non-Brucella bacteria and also with some bacterial and viral pathogens causing abortions. The assay was found to be specific as it did not detect any putative pathogens other than Brucella sp. Fifty-six clinical samples suspected for brucellosis (aborted fetal stomach content) were screened with PSR to validate the applicability of the test to detect Brucella DNA. The same samples were also screened with conventional PCR and real-time PCR. Of 56 samples, 25 samples were found to be positive with both PSR as well as real-time PCR, whereas only 20 samples were found positive with conventional PCR.

CONCLUSIONS

The results of this study indicated that the PSR assay is a simple, rapid, sensitive and specific method for the detection of Brucella sp. that may improve diagnostic potential in clinical laboratories or can be used at diagnostic laboratories with minimal infrastructure.

SIGNIFICANCE AND IMPACT OF THE STUDY

The PSR assay, because of its simplicity and low cost, can be preferred to other molecular methods in the diagnosis of infectious diseases.

Investigation of propagation dynamics of truncated vector vortex beams

In this Letter, we experimentally investigate the propagation dynamics of truncated vector vortex beams generated using a Sagnac interferometer. Upon focusing, the truncated vector vortex beam is found to regain its original intensity structure within the Rayleigh range. In order to explain such behavior, the propagation dynamics of a truncated vector vortex beam is simulated by decomposing it into the sum of integral charge beams with associated complex weights. We also show that the polarization of the truncated composite vector vortex beam is preserved all along the propagation axis. The experimental observations are consistent with theoretical predictions based on previous literature and are in good agreement with our simulation results. The results hold importance as vector vortex modes are eigenmodes of the optical fiber.

Draft genome sequence of field isolate Brucella melitensis strain 2007BM/1 from India

OBJECTIVES

Brucellosis is among one of the most widespread important global zoonotic diseases that is endemic in many parts of India. Brucella melitensis is supposed to be the most pathogenic species for humans. Here we report the draft genome sequence of B. melitensis strain 2007BM/1 isolated from a human in India.

METHODS

Genomic DNA was extracted from Brucella culture and was sequenced using an Illumina MiSeq platform. The generated reads were assembled using three de novo assemblers and the draft genome was annotated.

RESULTS

This monoisolate, with a genome length of 3268756bp, was found to be resistant to azithromycin and trimethoprim/sulfamethoxazole but susceptible to tetracycline, ofloxacin, rifampicin, ciprofloxacin and doxycycline. The presence of virulence genes in the strain was identified.

CONCLUSIONS

The results obtained will help in understanding drug resistance mechanisms and virulence factors in highly zoonotic B. melitensis and suggest the need for judicious use of antibiotics in livestock health and management practices.

Direct transfer of pump amplitude to parametric down-converted photons

In general, the spatial distribution of individual photons (signal or idler) generated by spontaneous parametric down-conversion (SPDC) does not evidently show any particular spatial mode structure because of their randomness in generation and the incoherent nature. Here, we numerically showed that all individual photons generated by the SPDC process carry the transverse amplitude as that of the pump and then confirmed it experimentally. The pump amplitude is revealed in SPDC when individual photons are spatially filtered from the total SPDC distribution. This is observed simply by imaging the photons that are filtered using a minimum-sized aperture. The phase measurements showed that the observed mode distribution does not possess the transverse phase distribution as that of the pump.

Superconducting properties and μSR study of the noncentrosymmetric superconductor Nb0.5Os0.5

The properties of the noncentrosymmetric superconductor (α-[Formula: see text] structure) Nb_0.5Os_0.5 have been investigated using resistivity, magnetization, specific heat, and muon spin relaxation and rotation (μSR) measurements. These measurements suggest that Nb_0.5Os_0.5 is a weakly coupled ([Formula: see text]) type-II superconductor ([Formula: see text]), having a bulk superconducting transition temperature T _c   =  3.07 K. The specific heat data fits well with the single-gap BCS model indicating nodeless s-wave superconductivity in Nb_0.5Os_0.5. The μSR measurements also confirm [Formula: see text]-wave superconductivity with the preserved time-reversal symmetry.