Spatial heterogeneity in global atmospheric CO during the COVID-19 lockdown: Implications for global and regional air quality policies

The COVID-19 lockdown (LD) provided a unique opportunity to examine the changes in regional and global air quality. Changes in the atmospheric carbon monoxide (CO) during LD warrant a thorough analysis as CO is a major air pollutant that affects human health, ecosystem and climate. Our analysis reveals a decrease of 5-10% in the CO column during LD (April-May 2020) compared to the pre-lockdown (PreLD, March 2020) periods in regions with high anthropogenic activity, such as East China (EC), Indo-Gangetic Plain (IGP), North America, parts of Europe and Russia. However, this reduction did not occur in the regions of frequent and intense wildfires and agricultural waste burning (AWB). We find high heterogeneity in the CO column distributions, from regional to city scales during the LD period. To determine the sources of CO emissions during LD, we examined the ratios of nitrogen dioxide (NO2), sulfur dioxide (SO2) to CO for major cities in the world. This facilitated the identification of contributions from different sources; including vehicles, industries and biomass burning during LD. The comparison between CO levels during the LD and PreLD periods indicates a notable reduction in the global tropospheric CO, but no significant change in the stratosphere. It is found that CO emissions decreased during LD in the hotspot regions, but rebounded after the LD restrictions were lifted. This study, therefore, highlights the importance of policy decisions and their implementations in the global and regional scales to improve the air quality, and thus to protect public health and environment.

Adoption of cleaner technologies and reduction in fire events in the hotspots lead to global decline in carbon monoxide

Carbon Monoxide (CO) is not a greenhouse gas (GHG), but has the capacity to change atmospheric chemistry of other GHGs such as methane and ozone, and therefore indirectly affects Earth's radiative forcing of the GHGs and surface temperature. Here, we use the CO mixing ratio at 850 hPa from the Tropospheric Emission Spectrometer (TES) reanalysis and the Measurement of Pollution in the Troposphere (MOPITT) satellite measurements for the period 2005-2019 to examine the spatio-temporal changes in CO across the latitudes. We find a substantial decrease in global CO, about 0.21 ± 0.09 ppb/yr (0.23 ± 0.12%/yr) with the TES data and about 0.36 ± 0.07 ppb/yr (0.45 ± 0.08%/yr) with the MOPITT satellite measurements during the study period. The highest CO decreasing trend is observed in Eastern China (2.7 ± 0.37 ppb/yr) followed by Myanmar (2.142 ± 0.59 ppb/yr) and South America (1.08 ± 0.82 ppb/yr). This negative trend in CO is primarily due to the decrease in biomass burning and stringent environmental regulations in the respective regions and countries. The sources including road transport that account for about 33.6% of CO emissions, followed by industries (18.3%) and agricultural waste burning (8.8%), might also be responsible for the reduction in CO due to adaptation of improved emission control technology and regulations in the past decade from 2005 to 2019. Therefore, the study provides new insights on the current trends of global CO distribution and reasons for recent reduction in global CO emissions, which would be useful for future decision-making process to control air pollution.

Search for Subsolar-Mass Binaries in the First Half of Advanced LIGO's and Advanced Virgo's Third Observing Run

We report on a search for compact binary coalescences where at least one binary component has a mass between 0.2  M_{⊙} and 1.0  M_{⊙} in Advanced LIGO and Advanced Virgo data collected between 1 April 2019 1500 UTC and 1 October 2019 1500 UTC. We extend our previous analyses in two main ways: we include data from the Virgo detector and we allow for more unequal mass systems, with mass ratio q≥0.1. We do not report any gravitational-wave candidates. The most significant trigger has a false alarm rate of 0.14  yr^{-1}. This implies an upper limit on the merger rate of subsolar binaries in the range [220-24200]  Gpc^{-3} yr^{-1}, depending on the chirp mass of the binary. We use this upper limit to derive astrophysical constraints on two phenomenological models that could produce subsolar-mass compact objects. One is an isotropic distribution of equal-mass primordial black holes. Using this model, we find that the fraction of dark matter in primordial black holes in the mass range 0.2  M_{⊙}<m_{PBH}<1.0  M_{⊙} is f_{PBH}≡Ω_{PBH}/Ω_{DM}≲6%. This improves existing constraints on primordial black hole abundance by a factor of ∼3. The other is a dissipative dark matter model, in which fermionic dark matter can collapse and form black holes. The upper limit on the fraction of dark matter black holes depends on the minimum mass of the black holes that can be formed: the most constraining result is obtained at M_{min}=1  M_{⊙}, where f_{DBH}≡Ω_{DBH}/Ω_{DM}≲0.003%. These are the first constraints placed on dissipative dark models by subsolar-mass analyses.

The mobilization of endogenous bi-specific natural killer T-like cells and independent of glucocorticoid receptor activation related to acute supra-pharmacologic weight-based dexamethasone (AVM0703) and 18 mgs/kg body weight

e14545

Background: Glucocorticoids (GC) are a common component of blood cancer regimens, at doses 40 mg or lower due to concerns of pancreatitis and hepatotoxicity (Walasik-Szemplińska et al. Thyroid Research (2019) 12:13; Ataallah et al. Cureus. 2020 Jul; 12(7)) and neuropsychiatric effects. AVM Biotechnology has developed a high concentration, high volume, preservative-free, patent pending formulation of dexamethasone (Dex) (AVM0703), allowing administration up to 21 mg/kg (1470 mg for 70 kg) in one-hour IV infusion. Prophylactic use of physiologic hydrocortisone reduces the risk of GC neuropsychiatric side-effects (Warris, L. T. et al. J. Clin. Oncol. (2016) 34:2287; Meijer & de Kloet Endocrinology (2017) 158:448). At supra-pharmacologic doses (>6 mg/kg) AVM0703 mobilizes endogenous bispecific gamma delta invariant TCR+ Natural Killer T-like cells (AVM-NKT) (PCT/US21/19773), via a non-GC receptor, that rapidly home to cancer in tumor models and are directly related to tumor killing. GCs have been reported to induce biological responses independent of GCRs: corticosterone has been shown to bind a G-protein coupled receptor that does not bind either Dex or aldosterone (Mitre-Aguilar, et. Al International Journal of Clinical and Experimental Pathology (2015) 8:1; Powell, C. E., et. Al. Endocrine (1999) 10: 271) and the non-GCR mineralocorticoid receptor has high affinity for prednisone but not Dex. Methods: a) Mouse splenocytes or human whole blood were incubated with Dex from 1nM to 1mM. Apoptosis was measured for human whole blood by CBCs and for mouse splenocytes by flow cytometry 4 to 6 hours later. RU486 was used to block expected transmembrane (tm)GCR activity. b) Naïve, tumor bearing and humanized mice were dosed with AVM0703 at human equivalent doses (HED) >18 mg/kg. Depending on the disease state of the mice, novel AVM-NKT were observed in the blood between 3 and 96 hours later, determined by flow cytometry. Results: a) Apoptosis via the tmGCR was observed at expected concentrations between 10nM and 100uM and was blocked by the GCR antagonist RU486. At concentrations above 250uM, which correspond to in vivo peak blood levels from acute 7mg/kg and greater, no Dex-induced apoptosis was observed. b) Acute supra-pharmacologic AVM0703 induced the appearance of CD3+, CD56+, gdTCR+, invariant TCR+ bi-specific Natural Killer T-like cells, that in a cancer setting also expressed activation markers like CD16 and NKp44. Intriguingly, the AVM-NKT also express B220 in certain settings, and CD3+ B220+ DP has been indicative of IL-2 or IL-12 lymphoma killing (Masztalerz, A, et. Al. Anticancer Res (2004) 24(5A):2633). Conclusions: CBC’s and clinical chemistries from enrolling clinical trial confirmed the in vitro non-GCR findings.

The effects of AVM0703 mobilization of endogenous gamma delta/invariant TCR+ bispecific natural killer T-like cells against solid tumors and blood cancers

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Background: Glucocorticoids (GC) are a common component of blood cancer regimens, typically at doses 40 mg or lower due to concerns of pancreatitis and hepatotoxicity (Walasik-Szemplińska et al. Thyroid Research. 2019;12:13; Ataallah et al. Cureus. 2020;12[7]) and neuropsychiatric effects. AVM Biotechnology has developed a high concentration, high volume, preservative-free, patent pending formulation of dexamethasone (AVM0703), that allows administration of up to 21 mg/kg (1470 mg for 70 kg) over a one-hour IV infusion. Prophylactic use of circadian physiologic hydrocortisone reduces the risk of GC neuropsychiatric side-effects (Warris LT, et al. J. Clin. Oncol. 2016;34:2287; Meijer & de Kloet Endocrinology. 2017;158:448). Acute supra-pharmacologic doses (>6 mg/kg) AVM0703 mobilizes endogenous bispecific gamma delta invariant TCR+ bi-specific Natural Killer T-like cells (AVM-NKT) (PCT/US21/19773), via a non-GC receptor, that rapidly home to diseased organs in preclinical models and are directly related to tumor killing, including Non-Hodgkin’s Lymphoma, Melanoma, and Multiple Myeloma. Methods: Cancer cell lines and (mouse host) were i) immune-resistant mouse A20 B lymphoma (Balb/c), ii) xenografted human T-ALL CCRF-CEM (NCRnu), iii) mouse B16F10 melanoma (B62DF1), and iv) mouse MOPC315 (Balb/c). Cancer cell lines were inoculated into the flank either as single cell suspensions or encased in Matrigel. When tumor volume reached between 100-500mm3 well-established tumors, mice were orally gavaged with a human equivalent dose (HED) of 15-18 mg/kg AVM0703 as monotherapy, or as a preconditioning prior to adoptive cell transfer (ACT), or in combination with chemotherapy. Responses were determined by tumor volume measurements, tumor immunohistochemistry or flow cytometry detection of residual cancer cells. Results: Immunohistochemistry analysis of tumors from AVM0703 treated mice demonstrated pseudoprogression similar to checkpoint inhibitors: i.e. tumors were measurable however in some cases all cancer cells had been eradicated. Therefore, subsequent tumor monitoring at end point was done by flow cytometry to quantify the total number of live cancer cells more accurately than tumor measurements by calipers or immunohistochemistry, due to pseudoprogression and limitations of examining only a few sections from each tumor. Conclusions: AVM0703 led to: i) complete response (CR) in 27% of immune-resistant mouse A20 tumors as monotherapy and CR in 60% when combined with 2 doses of cyclophosphamide/fludarabine (CyFlu); ii) tumor eradication and long-term memory against xenografted human T-ALL; iii) enhancement of ACT equivalent to CyFlu preconditioning in mouse melanoma; and iv) preliminary 95% CR against mouse multiple myeloma.

Reproductive stage- and season-dependent culture characteristics of enriched caprine male germline stem cells

The present study aims to evaluate season- and reproductive-stage dependent variation in culture characteristics and expression of pluripotency and adhesion markers in caprine-male germline stem cells (cmGSCs). For this, testes from pre-pubertal (4-6 months) and adult (~ 2 years) bucks during non-breeding (July-August; n = 4 each) and breeding (October-November; n = 4 each) seasons were used to isolated testicular cells by two-step enzymatic digestion. After cmGSCs enrichment by multiple methods (differential platting, Percoll density gradient centrifugation, and MACS), cell viability of CD90⁺ cells was assessed before co-cultured onto the Sertoli cell feeder layer up to 3^rd-passage (P-3). The culture characteristics of cmGSCs were compared during primary culture (P-0) and P-3 with different assays [BrdU-assay (proliferation), MTT-assay (senescence), and Cluster-forming activity-assay] and transcript expression analyses by qRT-PCR. Moreover, the co-localization of UCHL-1, CD90, and DBA was examined by a double-immunofluorescence method. In adult bucks, significantly (p < 0.05) higher cell numbers with the ability to proliferate faster and form a greater number of cell clusters, besides up-regulation of pluripotency and adhesion markers expression were observed during the breeding season than the non-breeding season. In contrast, such season-dependent variation was lacking in pre-pubertal bucks. The expression of transcripts during non-breeding seasons was significantly (p < 0.05) higher in pre-pubertal cmGSCs than in adult cells (UCHL-1 = 2.38-folds; CD-90 = 6.66-folds; PLZF = 20.87-folds; ID-4 = 4.75-folds; E-cadherin = 3.89-folds and β1-integrin = 5.70-folds). Overall, the reproductive stage and season affect the population, culture characteristics, and expression of pluripotency and adhesion specific markers in buck testis. These results provide an insight to develop an efficient system for successful cell culture processes targeting cmGSCs.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s10616-021-00515-x.

Temperature response of enriched pre-pubertal caprine male germline stem cells in vitro

The present study aims to evaluate culture temperature-dependent variation in survival, growth characteristics and expression of stress, pluripotency, apoptosis, and adhesion markers in enriched caprine male germline stem cells (cmGSCs). For this, testes from pre-pubertal bucks (4-5 months; n = 4) were used to isolated cells by a two-step enzymatic digestion method. After enrichment of cmGSCs by multiple methods (differential platting, Percoll density gradient centrifugation, and MACS), viability of CD90+ cells was assessed before co-cultured onto the Sertoli cell feeder layer at different temperatures (35.5, 37.0, 38.5, and 40.0 °C). The culture characteristics of cells were compared with MTT assay (viability); cluster-forming activity assay, SA-β1-gal assay (senescence), BrdU assay (proliferation), and transcript expression analyses by qRT-PCR. Moreover, the co-localization of pluripotency markers (UCHL-1, PLZF, and DBA) was examined by a double-immunofluorescence method. The cells grown at 37.0 °C showed faster proliferation with a significantly (p < 0.05) higher number of viable cells and greater number of cell clusters, besides higher expression of pluripotency markers. The transcript expression of HSPs (more noticeably HSP72 than HSP73), anti-oxidative enzymes (GPx and CuZnSOD), and adhesion molecule (β1-integrin) was significantly (p < 0.05) downregulated when grown at 35.0, 38.5, or 40.0 °C compared with 37.0 °C. The expression of pluripotency-specific transcripts was significantly (p < 0.05) lower in cmGSCs grown at the culture temperature lower (35.5 °C) or higher (38.5 °C and 40.0 °C) than 37.0 °C. Overall, the culture temperature significantly affects the proliferation, growth characteristics, and expression of heat stress, pluripotency, and adhesion-specific markers in pre-pubertal cmGSCs. These results provide an insight to develop strategies for the improved cultivation and downstream applications of cmGSCs.

P–172 Data-independent acquisition-proteomics of human embryo-spent medium and identification of potential embryo biomarkers

Study question

Can human embryo-derived protein(s) serve as viability biomarkers to predict pregnancy outcome, post embryo transfer?

Summary answer

The human embryo-spent medium proteome, using data-independent acquisition (DIA) approach, could identify novel biomarkers for use in elective embryo transfer.

What is known already

Morphological assessment is used for elective embryo transfer. To improve IVF outcomes and to avoid multiple gestations, embryo-viability assessment is required toward single embryo transfer. Embryo proteomics could provide a non-invasive approach to assess embryo viability. With the advent of DIA mode proteomics, a robust proteome of E-SM could be determined.

Study design, size, duration

This was a retrospective study performed between May and December, 2020 using ten E-SMs obtained from ten individual transferable-quality embryos. Frozen E-SMs, following post-thaw, were subjected to LC-MS-MS analysis. Identified proteome profiles were being potentially correlated to embryo quality scores and pregnancy outcomes in terms of live births.

Participants/materials, setting, methods

The E-SMs were processed for proteomic analysis and subjected to reduction, alkylation and trypsin digestion. Trypsin digested samples were desalted followed by LC-MS/MS using DIA method. Obtained results were searched against human peptide spectral library using Skyline. Differentially expressed proteins were identified by MSStat. Individual peptide peak area under the curve was normalized and analyzed using Student t-test. Fold change was calculated to identify differentially regulated proteins in blank and E-SM samples.

Main results and the role of chance

Using a high-resolution mass spectrometer and high throughput DIA method, we identified 5,502 peptides corresponding to 3,396 proteins from blank and E-SM samples, derived from five non-transferred embryos. We observed that 516 proteins were specific to E-SMs vies-a-vies those of embryo-free blank medium. Statistical analysis showed that 25 proteins were significantly present E-SMs vs. blank. Interestingly, we observed that 16 proteins were down regulated and 9 were up regulated in E-SMs vs. blank medium. Furthermore, E-SMs, from transferred embryos, contained 2,467 peptides corresponding to 1,741 proteins; of these, 1, 689 proteins were specific to E-SMs with 60 (58 down regulated and 2 up regulated) of them being significantly expressed in E-SMs vis-à-vis embryo-free blank medium. Considering the available met analysis published data, our study is the first to use DIA acquisition for high-throughput analysis of human embryo proteome and identification of biomarkers of embryo viability and for possible prediction of pregnancy outcome.

Limitations, reasons for caution

Proteins, other than HAS, detected in the blank medium could be because of non-purified HAS or undeclared proteins and DIA approach used. A large cohort study and meta-analysis using DIA mode are required to establish the embryo-proteome having predictive potential for embryo biological viability.

Wider implications of the findings: For the first time, using DIA mode, a global embryo proteome assessment could be made, establishing a novel embryo viability biomarkers. This, along with the morphological analysis, could be practiced for selection of transferable quality embryo(s)

Trial registration number

Not applicable

Low oxygen tension potentiates proliferation and stemness but not multilineage differentiation of caprine male germline stem cells

The milieu of male germline stem cells (mGSCs) is characterized as a low-oxygen (O₂) environment, whereas, their in-vitro expansion is typically performed under normoxia (20-21% O₂). The comparative information about the effects of low and normal O₂ levels on the growth and differentiation of caprine mGSCs (cmGSCs) is lacking. Thus, we aimed to investigate the functional and multilineage differentiation characteristics of enriched cmGSCs, when grown under hypoxia and normoxia. After enrichment of cmGSCs through multiple methods (differential platting and Percoll-density gradient centrifugation), the growth characteristics of cells [population-doubling time (PDT), viability, proliferation, and senescence], and expression of key-markers of adhesion (β-integrin and E-Cadherin) and stemness (OCT-4, THY-1 and UCHL-1) were evaluated under hypoxia (5% O₂) and normoxia (21% O₂). Furthermore, the extent of multilineage differentiation (neurogenic, adipogenic, and chondrogenic differentiation) under different culture conditions was assessed. The survival, viability, and proliferation were significantly (p < 0.05) improved, thus, yielding a significantly (p < 0.05) higher number of viable cells with larger colonies under hypoxia. Furthermore, the expression of stemness and adhesion markers were distinctly upregulated under lowered O₂ conditions. Conversely, the differentiated regions and expression of differentiation-specific genes [C/EBPα (adipogenic), nestin and β-tubulin (neurogenic), and COL2A1 (chondrogenic)] were significantly (p < 0.05) reduced under hypoxia. Overall, the results demonstrate that culturing cmGSCs under hypoxia augments the growth characteristics and stemness but not the multilineage differentiation of cmGSCs, as compared with normoxia. These data are important to develop robust methodologies for ex-vivo expansion and lineage-committed differentiation of cmGSCs for clinical applications.

The Reduced Nitridogermanates(III) Ca6 [Ge2 N6 ] and Sr6 [Ge2 N6 ] with Ge-Ge Bonds

The first nitridogermanates(III) Ca₆[Ge₂N₆] and Sr₆[Ge₂N₆] were synthesized from sodium flux and structurally characterized by powder and single crystal X‐ray diffraction, respectively. They crystallize isostructurally to each other and homeotypic to Ca₆[Cr₂N₆]H in space group R3‾ . They feature unprecedented, mutually isolated, ethane‐like [Ge^III₂N₆]¹²⁻ anions in a staggered conformation. The compounds are semiconductors according to resistivity measurements and electronic structure calculations, yielding band gaps of 1.1 eV for Ca₆[Ge₂N₆] and 0.2 eV for Sr₆[Ge₂N₆].

Thrombin in the Activation of the Fluid Contact Phase in Patients with Hereditary Angioedema Carrying the F12 P.Thr309Lys Variant

Hereditary angioedema due to pathogenic FXII variants (HAE-FXII) is a rare dominant disease caused by increased activation of the plasma contact system. The most prevalent HAE-FXII variant, c.1032C > A p.Thr309Lys (FXII^309Lys), results in a smaller FXII protein with increased sensitivity to fluid-phase activation by poorly understood mechanisms. We aimed to investigate the functionality of the FXII^309Lys variant in 33 HAE-FXII patients, 25 healthy controls and 46 patients with congenital disorders of glycosylation (CDG). Activation of the plasma contact system was assessed by western blot and amidolytic assay in basal conditions or after treatment with either artificial or physiological activators. Recombinant wild-type and FXII^309Lys variants were expressed in S2 insect (Drosophila) cells. Amidolytic and fibrin generation assays were performed in fresh plasma samples. FXII^309Lys samples exhibited an increased electrophoretic mobility comparable with N-glycan-deficient FXII from CDG patients and asialo-FXII generated by neuraminidase treatment. They presented increased sensitivity to activation by dextran sulphate and silica which resulted in the generation of an aberrant 37-kDa heavy chain. We did not observe increased susceptibility of FXII^309Lys to proteolysis by exogenous or tPA-generated plasmin. However, both exogenous and endogenous thrombin cleaved the FXII^309Lys variant, releasing a 37-kDa fragment and resulting in enhanced proteolytic activation on the fluid phase. This model supports a sequential proteolytic activation process involving thrombin priming of FXII^309Lys, followed by kallikrein cleavage and generation of active βFXIIa. The present results and the observation that angioedema episodes in HAE-FXII patients occur predominantly during hypercoagulable situations suggest a key role for thrombin.

The Regulatory Function of CCR9+ Dendritic Cells in Inflammation and Autoimmunity

Chemokine receptor CCR9 is a G protein–coupled receptor and expressed on several types of immune cells, including dendritic cells (DCs), CD4⁺ T cells, and B cells. CCR9 drives the migration of immune cells to gradients of its cognate ligand CCL25. The chemokine CCL25 is mostly produced by gut and thymic epithelial cells. Gut- and thymic-homing DCs are known to express CCR9, and these cells are predominantly localized in the gut lining and thymus. CCR9⁺ DCs are implicated in regulating inflammation, food allergy, alloimmunity, and autoimmunity. Differential interaction of CCR9⁺ DCs with lymphoid and myeloid cells in the thymus, secondary lymphoid tissues, and mucosal sites offer crucial insights to immune regulation. In this review, we examine the phenotypes, distributions, and interactions of CCR9⁺ DCs with other immune cells, elucidating their functions and role in inflammation and autoimmunity.

CCR9+ dendritic cells promote the differentiation of Foxp3+ regulatory CD4 T cells

Chemokine receptor CCR9 is known to play an important role in the migration of immune cells to the gut. Intestinal epithelial cells under gut inflammation or in inflammatory bowel disease (IBD) produce several folds higher CCL25, the only known ligand for CCR9, and drive the recruitment of CCR9+ immune cells. Due to its gut tropism activity, CCR9 and CCL25 are suggested as a potential therapeutic target. Still, many of the clinical trials targeting CCR9/CCL25 did not give a positive outcome; instead, they increase the severity of the disease. The non-chemotactic function of CCR9 in the gut inflammation and immunity is not known.

Using dextran sodium sulfate (DSS)-induced gut inflammation model in C57BL/6 mice, we showed that CCR9+ DCs, specifically CD11b−CD103+ DCs recruited in high frequency to the gut and gut-associated lymphoid tissues (GALT) in DSS treated mice as compared to control group. These CCR9+ DCs showed lower MHC II and CD86 molecules and had higher regulatory surface markers (FasL and Latency-associated peptide, LAP) in the GALT. Further, we demonstrate that thymic stromal lymphopoietin (TSLP) produced by CCR9+ DCs but not IL-10 or TGF-β, promotes the differentiation of Foxp3+ Treg. Furthermore, adoptive transfer of CCR9+ DCs in C57BL/6 mice promoted Tregs but reduced the Th17 cells in the GALT, and also suppressed the ovalbumin-specific gut allergic immune response. Together, these results suggest that CCR9+ DCs have a regulatory function and can be explored as an adoptive cellular therapy to control the gut inflammation and allergic immune response.

Global, Regional, and National Levels and Trends in Burden of Oral Conditions from 1990 to 2017: A Systematic Analysis for the Global Burden of Disease 2017 Study

Government and nongovernmental organizations need national and global estimates on the descriptive epidemiology of common oral conditions for policy planning and evaluation. The aim of this component of the Global Burden of Disease study was to produce estimates on prevalence, incidence, and years lived with disability for oral conditions from 1990 to 2017 by sex, age, and countries. In addition, this study reports the global socioeconomic pattern in burden of oral conditions by the standard World Bank classification of economies as well as the Global Burden of Disease Socio-demographic Index. The findings show that oral conditions remain a substantial population health challenge. Globally, there were 3.5 billion cases (95% uncertainty interval [95% UI], 3.2 to 3.7 billion) of oral conditions, of which 2.3 billion (95% UI, 2.1 to 2.5 billion) had untreated caries in permanent teeth, 796 million (95% UI, 671 to 930 million) had severe periodontitis, 532 million (95% UI, 443 to 622 million) had untreated caries in deciduous teeth, 267 million (95% UI, 235 to 300 million) had total tooth loss, and 139 million (95% UI, 133 to 146 million) had other oral conditions in 2017. Several patterns emerged when the World Bank’s classification of economies and the Socio-demographic Index were used as indicators of economic development. In general, more economically developed countries have the lowest burden of untreated dental caries and severe periodontitis and the highest burden of total tooth loss. The findings offer an opportunity for policy makers to identify successful oral health strategies and strengthen them; introduce and monitor different approaches where oral diseases are increasing; plan integration of oral health in the agenda for prevention of noncommunicable diseases; and estimate the cost of providing universal coverage for dental care.

CCR9 signaling in dendritic cells drives the differentiation of Foxp3+ Tregs and suppresses the allergic IgE response in the gut

The chemokine receptor CCR9 and its only known ligand CCL25 play an important role in gut inflammation and autoimmune colitis. The function of CCR9-CCL25 in the migration of immune cells is well characterized. However, its role in the immune cell differentiation is mostly not known. Using dextran sodium sulfate (DSS)-induced gut inflammation model, we showed that CCR9⁺ dendritic cells (DCs) specifically CD11b^- CD103⁺ DCs were significantly increased in the gut-associated lymphoid tissues (GALT) compared to control mice. These CCR9⁺ DCs express lower MHC II and CD86 molecules and had regulatory surface markers (FasL and latency-associated peptide, LAP) in the GALT. In the presence of CCL25, CCR9⁺ DCs promoted in vitro differentiation of Foxp3⁺ regulatory CD4⁺ T cells (Tregs). CCL25-induced differentiation of Tregs was due to intrinsic signaling in the DCs but not through CD4⁺ T cells, which was driven by the production of thymic stromal lymphopoietin (TSLP) and not IL-10. Furthermore, adoptive transfer of CCR9⁺ DCs in C57BL/6 mice promoted Tregs but reduced the Th17 cells in the GALT, and also suppressed the OVA-specific gut-allergic response. Our results suggest CCR9⁺ DCs have a regulatory function and may provide a new cellular therapeutic strategy to control gut inflammation and allergic immune reaction.

A TLR4-derived non-cytotoxic, self-assembling peptide functions as a vaccine adjuvant in mice

Vaccination is devised/formulated to stimulate specific and prolonged immune responses for long-term protection against infection or disease. A vaccine component, namely adjuvant, enhances antigen recognition by the host immune system and thereby stimulates its cellular and adaptive responses. Especially synthetic Toll-like receptor (TLR) agonists having self-assembling properties are considered as good candidates for adjuvant development. Here, a human TLR4-derived 20-residue peptide (TR-433), present in the dimerization interface of the TLR4-myeloid differentiation protein-2 (MD2) complex, displayed self-assembly and adopted a nanostructure. Both in vitro studies and in vivo experiments in mice indicated that TR-433 is nontoxic. TR-433 induced pro-inflammatory responses in THP-1 monocytes and HEK293T cells that were transiently transfected with TLR4/CD14/MD2 and also in BALB/c mice. In light of the self-assembly and pro-inflammatory properties of TR-433, we immunized with a mixture of TR-433 and either ovalbumin or filarial antigen trehalose-6-phosphate phosphatase (TPP). A significant amount of IgG titers was produced, suggesting adjuvanting capability of TR-433 that was comparable with that of Freund's complete adjuvant (FCA) and appreciably higher than that of alum. We found that TR-433 preferentially activates type 1 helper T cell (T_h1) response rather than type 2 helper T cell (T_h2) response. To our knowledge, this is the first report on the identification of a short TLR4-derived peptide that possesses both self-assembling and pro-inflammatory properties and has significant efficacy as an adjuvant, capable of activating cellular responses in mice. These results indicate that TR-433 possesses significant potential for development as a new adjuvant in therapeutic application.

A Type 1 Diabetes Genetic Risk Score Predicts Progression of Islet Autoimmunity and Development of Type 1 Diabetes in Individuals at Risk

OBJECTIVE

We tested the ability of a type 1 diabetes (T1D) genetic risk score (GRS) to predict progression of islet autoimmunity and T1D in at-risk individuals.

RESEARCH DESIGN AND METHODS

We studied the 1,244 TrialNet Pathway to Prevention study participants (T1D patients' relatives without diabetes and with one or more positive autoantibodies) who were genotyped with Illumina ImmunoChip (median [range] age at initial autoantibody determination 11.1 years [1.2-51.8], 48% male, 80.5% non-Hispanic white, median follow-up 5.4 years). Of 291 participants with a single positive autoantibody at screening, 157 converted to multiple autoantibody positivity and 55 developed diabetes. Of 953 participants with multiple positive autoantibodies at screening, 419 developed diabetes. We calculated the T1D GRS from 30 T1D-associated single nucleotide polymorphisms. We used multivariable Cox regression models, time-dependent receiver operating characteristic curves, and area under the curve (AUC) measures to evaluate prognostic utility of T1D GRS, age, sex, Diabetes Prevention Trial-Type 1 (DPT-1) Risk Score, positive autoantibody number or type, HLA DR3/DR4-DQ8 status, and race/ethnicity. We used recursive partitioning analyses to identify cut points in continuous variables.

RESULTS

Higher T1D GRS significantly increased the rate of progression to T1D adjusting for DPT-1 Risk Score, age, number of positive autoantibodies, sex, and ethnicity (hazard ratio [HR] 1.29 for a 0.05 increase, 95% CI 1.06-1.6; P = 0.011). Progression to T1D was best predicted by a combined model with GRS, number of positive autoantibodies, DPT-1 Risk Score, and age (7-year time-integrated AUC = 0.79, 5-year AUC = 0.73). Higher GRS was significantly associated with increased progression rate from single to multiple positive autoantibodies after adjusting for age, autoantibody type, ethnicity, and sex (HR 2.27 for GRS >0.295, 95% CI 1.47-3.51; P = 0.0002).

CONCLUSIONS

The T1D GRS independently predicts progression to T1D and improves prediction along T1D stages in autoantibody-positive relatives.

Assessment of the protein interaction between coagulation factor XII and corn trypsin inhibitor by molecular docking and biochemical validation

Essentials Corn Trypsin Inhibitor (CTI) is a selective inhibitor of coagulation Factor XII (FXII). Molecular modelling of the CTI-FXIIa complex suggested a canonical inhibitor binding mode. Mutagenesis revealed the CTI inhibitory loop and helices α1 and α2 mediate the interaction. This confirms that CTI inhibits FXII in canonical fashion and validates the molecular model.

SUMMARY

Background Corn trypsin inhibitor (CTI) has selectivity for the serine proteases coagulation factor XII and trypsin. CTI is in widespread use as a reagent that specifically inhibits the intrinsic pathway of blood coagulation but not the extrinsic pathway. Objectives To investigate the molecular basis of FXII inhibition by CTI. Methods We performed molecular docking of CTI, using its known crystal structure, with a model of the activated FXII (FXIIa) protease domain. The interaction model was verified by use of a panel of recombinant CTI variants tested for their ability to inhibit FXIIa enzymatic activity in a substrate cleavage assay. Results The docking predicted that: (i) the CTI central inhibitory loop P1 Arg34 side chain forms a salt bridge with the FXIIa S1 pocket Asp189 side chain; (ii) Trp22 from CTI helix α1 interacts with the FXIIa S3 pocket; and (iii) Arg43 from CTI helix α2 forms a salt bridge with FXIIa H1 pocket Asp60A. CTI amino acid substitution R34A negated all inhibitory activity, whereas the G32W, L35A, W22A and R42A/R43A substitutions reduced activity by large degrees of 108-fold, 41-fold, 158-fold, and 100-fold, respectively; the R27A, W37A, W39A and R42A substitutions had no effect. Synthetic peptides spanning CTI residues 20-44 had inhibitory activity that was three-fold to 4000-fold less than that of full-length CTI. Conclusions The data confirm the validity of a canonical model of the FXIIa-CTI interaction, with helix α1 (Trp22), central inhibitory loop (Arg34) and helix α2 (Arg43) of CTI being required for effective binding by contacting the S1, S3 and H1 pockets of FXIIa, respectively.

Effects of dietary supplementation of cinnamaldehyde and formic acid on growth performance, intestinal microbiota and immune response in broiler chickens

An experiment was conducted to investigate the effects of replacing antibiotic growth promoter (AGP) with a combination of essential oil and organic acids (EO + OA) on growth performance, gut microbiota and immune response in broiler chickens. In Experiment 1, 320 day-old broiler chicks were randomly distributed to 32 pens with 10 birds in each pen and the pens were equally allotted to four treatment groups. In Experiment 2, 120 day-old chicks were divided into the same four treatment groups, each group containing three replicated pens with 10 birds in each pen. The groups were (1) Negative Control (NC) without AGP or other growth-promoting feed additives; (2) AGP (NC + enramycin; 125 mg/kg feed; (3) OA (NC + OA; 500 mg/kg feed); and (4) EO + OA (NC + a combination of cinnamaldehyde and calcium formate; 500 mg/kg feed). Experiment 1 lasted for 40 days, whereas Experiment 2 continued for 28 days. In Experiment 2, all birds were orally challenged with Escherichia coli (108 bacteria/bird) on Day 14. Overall intake, growth and feed conversion ratio (FCR) on Day 40 had no difference (P > 0.05) among the groups in Experiment 1. In Experiment 2, growth, feed intake and FCR were not affected by any dietary treatments until Day 14, but after being challenged with E. coli, bodyweight gain and FCR improved (P < 0.05) for AGP and EO + OA compared with NC. Mortality rate was also lower (P < 0.05) for AGP and EO + OA than NC in Experiment 2. Villi height was higher (P < 0.001) in OA and EO + OA groups compared with NC and AGP groups. Any treatment did not affect (P > 0.05) the counts of total bacteria, E. coli and Lactobacillus in the contents of ileum and caecum. However, Salmonella counts in the ileal and caecal contents decreased (P < 0.001) for AGP, OA and EO + OA compared with NC group. Clostridium counts were lower for EO + OA group than for NC and AGP groups in the ileum, and for AGP, OA and EO + OA groups than for NC in the caeca (P < 0.05). Antibody titer on Day 35 against Newcastle disease vaccine was higher in EO + OA group than in NC, AGP and OA groups (P < 0.001). In conclusion, EO + OA did not affect growth and FCR in broilers. However, AGP and EO + AO improved growth performance and FCR after being challenged with E. coli. Moreover, EO + OA was effective in reducing the Clostridium count in the small intestine and caecum and increasing the villus height and antibody titer against Newcastle disease vaccine.

Utilization of Euryale ferox Salisbury seed shell for removal of basic fuchsin dye from water: equilibrium and kinetics investigation

Euryale ferox Salisbury (E. ferox) is an environmentally and economically important wetland macrophyte.

Regulatory T-cell neutralization in mice during filariasis helps in parasite clearance by enhancing T helper type 17-mediated pro-inflammatory response

Lymphatic filariasis leads to profound impairment of parasite-specific T helper type 1 (Th1) and Th2 immune responses and significantly increases the expression of regulatory networks and regulatory effectors like transforming growth factor-β, CD25, cytotoxic T-lymphocyte antigen 4, glucocorticoid-induced tumour necrosis factor receptor (GITR) and regulatory T (Treg) cells, which together play an important role in immunosuppression. While Treg cells suppress the activity of effector cells, monocyte dysfunction, characterized by an alternatively activated immunoregulatory phenotype, is one hypothesis that explains the lack of an antigen-specific T-cell response in infected individuals. In the present study, we administered neutralizing antibodies against the Treg cell-associated markers CD25 and GITR and observed its effects on filaria-induced immunosuppression. Our results show that administration of anti-CD25 and anti-GITR in infected animals not only arrested the accumulation of Treg cells and reduced arginase activity, but also led to an increase in the percentages of Th17 cells in the secondary lymphoid organs of mice. Elevated levels of interferon-γ and decreased levels of interleukin-10 were also noted in the culture supernatants of mouse splenocytes that were treated with neutralizing antibodies. Furthermore, treatment with neutralizing antibodies enhanced the expression of inducible nitric oxide synthase on host macrophages and CD40 on host dendritic cells with concomitant decreased expression of alternative activation markers Arg1, Ym1 and Fizz1, which together lead to reduced parasite burden in treated animals. In summary, administration of neutralizing antibodies helps in breaking the regulatory network in mice and limits parasite-induced immunosuppression at the earliest host-parasite interface.

Wolbachia endosymbiont of Brugia malayi elicits a T helper type 17-mediated pro-inflammatory immune response through Wolbachia surface protein

Wolbachia is an endosymbiotic bacterium of the filarial nematode Brugia malayi. The symbiotic relationship between Wolbachia and its filarial host is dependent on interactions between the proteins of both organisms. However, little is known about Wolbachia proteins that are involved in the inflammatory pathology of the host during lymphatic filariasis. In the present study, we cloned, expressed and purified Wolbachia surface protein (r-wsp) from Wolbachia and administered it to mice, either alone or in combination with infective larvae of B. malayi (Bm-L3) and monitored the developing immune response in infected animals. Our results show that spleens and mesenteric lymph nodes of mice immunized with either r-wsp or infected with Bm-L3 show increased percentages of CD4(+) T helper type 17 (Th17) cells and Th1 cytokines like interferon-γ and interleukin-2 (IL-2) along with decreased percentages of regulatory T cells, Th2 cytokines like IL-4 and IL-10 and transforming growth factor β (TGF-β) levels in culture supernatants of splenocytes. These observations were stronger in mice immunized with r-wsp alone. Interestingly, when mice were first immunized with r-wsp and subsequently infected with Bm-L3, percentages of CD4(+) Th17 cells and Th1 cytokines increased even further while that of regulatory T cells, Th2 cytokines and TGF-β levels decreased. These results for the first time show that r-wsp acts synergistically with Bm-L3 in promoting a pro-inflammatory response by increasing Th17 cells and at the same time diminishes host immunological tolerance by decreasing regulatory T cells and TGF-β secretion.

Coagulation factor XII protease domain crystal structure

BACKGROUND

Coagulation factor XII is a serine protease that is important for kinin generation and blood coagulation, cleaving the substrates plasma kallikrein and FXI.

OBJECTIVE

To investigate FXII zymogen activation and substrate recognition by determining the crystal structure of the FXII protease domain.

METHODS AND RESULTS

A series of recombinant FXII protease constructs were characterized by measurement of cleavage of chromogenic peptide and plasma kallikrein protein substrates. This revealed that the FXII protease construct spanning the light chain has unexpectedly weak proteolytic activity compared to β-FXIIa, which has an additional nine amino acid remnant of the heavy chain present. Consistent with these data, the crystal structure of the light chain protease reveals a zymogen conformation for active site residues Gly193 and Ser195, where the oxyanion hole is absent. The Asp194 side chain salt bridge to Arg73 constitutes an atypical conformation of the 70-loop. In one crystal form, the S1 pocket loops are partially flexible, which is typical of a zymogen. In a second crystal form of the deglycosylated light chain, the S1 pocket loops are ordered, and a short α-helix in the 180-loop of the structure results in an enlarged and distorted S1 pocket with a buried conformation of Asp189, which is critical for P1 Arg substrate recognition. The FXII structures define patches of negative charge surrounding the active site cleft that may be critical for interactions with inhibitors and substrates.

CONCLUSIONS

These data provide the first structural basis for understanding FXII substrate recognition and zymogen activation.

Production of a non-cytotoxic bioflocculant by a bacterium utilizing a petroleum hydrocarbon source and its application in heavy metal removal

A bacterium isolated from the activated sludge of an oil refinery of Assam, India retained efficient bioflocculating activity through production of the bioflocculant when it was grown on a crude oil amended medium void of any other carbon source.

Moxidectin causes adult worm mortality of human lymphatic filarial parasite Brugia malayi in rodent models

Moxidectin is a macrocyclic lactone belonging to milbemycin family closely related to ivermectin and is currently progressing towards Phase III clinical trial against human infection with the filaria Onchocerca volvulus (Leuckart, 1894). There is a single report on the microfilaricidal and embryostatic activity of moxidectin in case of the human lymphatic filarial parasite Brugia malayi (Brug, 1927) in Mastomys coucha (Smith) but without any adulticidal action. In the present study, the in vitro and in vivo antifilarial efficacy of moxidectin was evaluated on, B. malayi. In vitro moxidectin showed 100% reduction in adult female worm motility at 0.6 μM concentration within 7 days with 68% inhibition in the reduction of MTT (3-(4, 5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide dye) (which is used to detect viability of worms). A 50% inhibitory concentration (IC50) of moxidectin for adult female parasite was 0.242 μM, for male worm 0.186 μM and for microfilaria IC50 was 0.813 μM. In adult B. malayi-transplanted primary screening model (Meriones unguiculatus Milne-Edwards), moxidectin at a single optimal dose of 20 mg/kg by oral and subcutaneous route was found effective on both adult parasites and microfilariae. In secondary screening (M coucha, subcutaneously inoculated with infective larvae), moxidectin at the same dose by subcutaneous route brought about death of 49% of adult worms besides causing sterilisation in 54% of the recovered live female worms. The treated animals exhibited a continuous and sustained reduction in peripheral blood microfilaraemia throughout the observation period of 90 days. The mechanism of action of moxidectin is suggested to be similar to avermectins. The in silico studies were also designed to explore the interaction of moxidectin with glutamate-gated chloride channels of B. malayi. The docking results revealed a close interaction of moxidectin with various GluCl ligand sites of B. malayi.

In vitro gene silencing of independent phosphoglycerate mutase (iPGM) in the filarial parasite Brugia malayi

BACKGROUND

The phosphoglycerate mutase (PGM) enzyme catalyzes the interconversion of 2- and 3-phosphoglycerate in the glycolytic /gluconeogenic pathways that are present in the majority of cellular organisms. They can be classified as cofactor-dependent PGM (dPGM) or cofactor-independent PGM (iPGM). Vertebrates, yeasts, and many bacteria have only dPGM, while higher plants, nematodes, archaea, and many other bacteria have only iPGM. A small number of bacteria, including Escherichia coli and certain archaea and protozoa, contain both forms. The silencing of ipgm in Caenorhabditis elegans (C. elegans) has demonstrated the importance of this enzyme in parasite viability and, therefore, its potential as an anthelmintic drug target. In this study, the role of the Brugia malayi (B. malayi) ipgm in parasite viability, microfilaria release, embryogenesis, and in vivo development of infective larvae post-gene silencing was explored by applying ribonucleic acid (RNA) interference studies.

RESULTS

The in vitro ipgm gene silencing by small interfering RNA (siRNA) leads to severe phenotypic deformities in the intrauterine developmental stages of female worms with a drastic reduction (~90%) in the motility of adult parasites and a significantly reduced (80%) release of microfilariae (mf) by female worms in vitro. Almost half of the in vitro-treated infective L3 displayed sluggish movement. The in vivo survival and development of siRNA-treated infective larvae (L3) was investigated in the peritoneal cavity of jirds where a ~45% reduction in adult worm establishment was observed.

CONCLUSION

The findings clearly suggest that iPGM is essential for both larval and adult stages of B. malayi parasite and that it plays a pivotal role in female worm embryogenesis. The results thus validate the Bm-iPGM as a putative anti-filarial drug target.

Structure of plasma and tissue kallikreins

The kallikrein kinin system (KKS) consists of serine proteases involved in the production of peptides called kinins, principally bradykinin and Lys-bradykinin (kallidin). The KKS contributes to a variety of physiological processes including inflammation, blood pressure control and coagulation. Here we review the protein structural data available for these serine proteases and examine the molecular mechanisms of zymogen activation and substrate recognition focusing on plasma kallikrein (PK) and tissue kallikrein (KLK1) cleavage of kininogens. PK circulates as a zymogen bound to high-molecular-weight kininogen (HK). PK is activated by coagulation factor XIIa and then cleaves HK to generate bradykinin and factor XII to generate further XIIa.A structure has been described for the activated PK protease domain in complex with the inhibitor benzamidine. Kallikrein-related peptidases (KLKs) have a distinct domain structure and exist as a family of 15 genes which are differentially expressed in many tissues and the central nervous system.They cleave a wide variety of substrates including low-molecular-weight kininogen (LK) and matrix proteins. Crystal structures are available for KLK1, 3, 4, 5, 6 and 7 activated protease domains typically in complex with S1 pocket inhibitors. A substrate mimetic complex is described for KLK3 which provides insight into substrate recognition. A zymogen crystal structure determined for KLK6 reveals a closed S1 pocket and a novel mechanism of zymogen activation. Overall these structures have proved highly informative in understanding the molecular mechanisms of the KKS and provide templates to design inhibitors for treatment of a variety of diseases.

N-Methyl-6, 7-dimethoxyisoquinolone in Annona squamosa twigs is the major immune modifier to elicit polarized Th1 immune response in BALB/c mice

Annona squamosa (AS) has traditionally been used as ethnomedicine. We have earlier extracted and fractionated the twigs of AS based upon its bioactivity and observed its immune potentiating activity that was localized in its three fractions. Present communication deals with the phytochemical analysis and pharmacological investigation of the most active chloroform fraction that led to isolation and identification of a number of compounds whose structures were elucidated using 1D and 2D NMR spectroscopic analysis. Amongst the twelve pure compounds isolated, five compounds Lanuginosine (1), (+)-O-methylarmepavine (2), (+)-anomuricine (3), Isocorydine (4), and N-methyl-6, 7-dimethoxyisoquinolone (5) were evaluated in vivo for their immune modifier activities in BALB/c mice after oral administration at three log doses of 0.3, 1.0 and 3.0mg/kg for 14 consecutive days. Of these, three compounds (1, 2 and 5) showed dose dependent immune stimulating activity. However, the uppermost activity was noted in the compound N-methyl-6, 7-dimethoxyisoquinolone at the 3.0mg/kg oral dose. The activity was assessed in the form of increased splenic T and B cellular proliferation, up-regulated CD4+, CD8+ and CD19+ cell population and accentuation in the peritoneal macrophage function. The compound possibly acted modifying the expression of Th1- and Th2- cytokines via stimulation of pro-inflammatory Th1 cytokines IL-2 and IFN-γ. These results warrant the use of the above compounds as an efficient immune-stimulant or immune-adjuvant against diseases with immune suppression. The analogs of the compound may further be chemically synthesized to achieve desired immune modifying activity.