Association of Donor Vascular Endothelial Growth Factor Gene Polymorphism With Acute Renal Allograft Rejection.

BACKGROUND: Recipient's VEGF-A polymorphisms have been reported to be associated with the risk of acute allograft rejection. However, an association of the donor's VEGF-A gene polymorphism with rejection remained unelucidated till now. METHODS: In this study, VEGF-A gene SNPs at nine loci were analyzed in 160 kidney donors and recipients with rejection (rejectors, n = 80) and without rejection (non-rejectors, n = 80). Blood VEGF-A mRNA, plasma VEGF level, and intragraft VEGF expression were also analyzed by RT-PCR, ELISA, and immunohistochemistry, respectively. RESULTS: On comparing between the donor and rejectors, the polymorphic genotypes of VEGF -634 C>G [GG genotype, p < 0.0001; OR (95% CI) = 17.74 (5.16-60.96)]; VEGF -1154 G>A [AG genotype, p < 0.0001, OR (95% CI) = 16.07 (3.68-70.15)]; VEGF +936 C>T [CT genotype, p < 0.0001, OR (95% CI) = 178.64 (23.28-1370.9), and TT genotype, p < 0.0001; OR (95% CI) = 3149 (278.91-35 553)]; VEGF -1455 T>C [CC genotype, p value = 0.0464, OR (95% CI) = 3.13 (1.07-9.10)]; VEGF -2578 C>A [CA genotype, p = 0.0426, OR (95% CI) = 4.62 (1.03-20.59), and AA genotype, p value < 0.0001, OR (95% CI) = 21.89 (4.94-97.04)]; VEGF -2549 18 bp Insertion/Deletion [ID genotype, p value < 0.0001, OR (95% CI) = 27.27 (3.61-205.73) and DD genotype, p value < 0.0001, OR (95% CI) = 25.18 (3.30-191.89) were significantly associated with acute rejection risk. On comparing rejectors versus non-rejectors, GA genotype of VEGF -1190 G>A and TC genotype of VEGF -1455 T>C were associated with the risk of rejection. On comparing donor VEGF between rejectors and non-rejectors, CG genotype of VEGF -634 C>G, AG of VEGF -1154 G>A; GA of VEGF -1190 G>A were associated with rejection. The blood VEGF-A mRNA and plasma VEGF levels were higher in the rejectors group compared to non-rejectors. CONCLUSIONS: Besides the recipient's VEGF SNPS, the donor's VEGF SNPs are also associated with the risk of acute rejection and may be closely monitored in evaluation to determine the risk of rejection.

Lead and calcium crosstalk tempted acrosome damage and hyperpolarization of spermatozoa: signaling and ultra-structural evidences.

BACKGROUND: Exposure of humans and animals to heavy metals is increasing day-by-day; thus, lead even today remains of significant public health concern. According to CDC, blood lead reference value (BLRV) ranges from 3.5 µg/dl to 5 µg/dl in adults. Recently, almost 2.6% decline in male fertility per year has been reported but the cause is not well established. Lead (Pb2+) affects the size of testis, semen quality, and secretory functions of prostate. But the molecular mechanism(s) of lead toxicity in sperm cells is not clear. Thus, present study was undertaken to evaluate the adverse effects of lead acetate at environmentally relevant exposure levels (0.5, 5, 10 and 20 ppm) on functional and molecular dynamics of spermatozoa of bucks following in vitro exposure for 15 min and 3 h. RESULTS: Lead significantly decreased motility, viable count, and motion kinematic patterns of spermatozoa like curvilinear velocity, straight-line velocity, average path velocity, beat cross frequency and maximum amplitude of head lateral displacement even at 5 ppm concentration. Pb2+ modulated intracellular cAMP and Ca2+ levels in sperm cells through L-type calcium channels and induced spontaneous or premature acrosome reaction (AR) by increasing tyrosine phosphorylation of sperm proteins and downregulated mitochondrial transmembrane potential. Lead significantly increased DNA damage and apoptosis as well. Electron microscopy studies revealed Pb2+ -induced deleterious effects on plasma membrane of head and acrosome including collapsed cristae in mitochondria. CONCLUSIONS: Pb2+ not only mimics Ca2+ but also affects cellular targets involved in generation of cAMP, mitochondrial transmembrane potential, and ionic exchange. Lead seems to interact with Ca2+ channels because of charge similarity and probably enters the sperm cell through these channels and results in hyperpolarization. Our findings also indicate lead-induced TP and intracellular Ca2+ release in spermatozoa which in turn may be responsible for premature acrosome exocytosis which is essential feature of capacitation for fertilization. Thus, lead seems to reduce the fertilizing capacity of spermatozoa even at 0.5 ppm concentrations.

B-cell receptor signaling and genetic lesions in TP53 and CDKN2A/CDKN2B cooperate in Richter transformation.

B-cell receptor (BCR) signals play a critical role in the pathogenesis of chronic lymphocytic leukemia (CLL), but their role in regulating CLL cell proliferation has still not been firmly established. Unlike normal B cells, CLL cells do not proliferate in vitro upon engagement of the BCR, suggesting that CLL cell proliferation is regulated by other signals from the microenvironment, such as those provided by Toll-like receptors or T cells. Here, we report that BCR engagement of human and murine CLL cells induces several positive regulators of the cell cycle, but simultaneously induces the negative regulators CDKN1A, CDKN2A, and CDKN2B, which block cell-cycle progression. We further show that introduction of genetic lesions that downregulate these cell-cycle inhibitors, such as inactivating lesions in CDKN2A, CDKN2B, and the CDKN1A regulator TP53, leads to more aggressive disease in a murine in vivo CLL model and spontaneous proliferation in vitro that is BCR dependent but independent of costimulatory signals. Importantly, inactivating lesions in CDKN2A, CDKN2B, and TP53 frequently co-occur in Richter syndrome (RS), and BCR stimulation of human RS cells with such lesions is sufficient to induce proliferation. We also show that tumor cells with combined TP53 and CDKN2A/2B abnormalities remain sensitive to BCR-inhibitor treatment and are synergistically sensitive to the combination of a BCR and cyclin-dependent kinase 4 and 6 (CDK4/6) inhibitor both in vitro and in vivo. These data provide evidence that BCR signals are directly involved in driving CLL cell proliferation and reveal a novel mechanism of Richter transformation.

Higher pro-inflammatory cytokines IL-6 and IFN-γ are associated with anti-SARS-CoV-2 spike protein-specific seroconversion in renal allograft recipients.

BACKGROUND: Maintenance immunosuppressive regimens are speculated to hamper immunogenic response against severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) in renal transplant recipients (RTRs) compared to the healthy population. Healthy people with SARS-CoV-2 infection often develop neutralizing antibodies and secret copious quantities of cytokines, leading to virus clearance and sometimes more severe immune-related complications. METHODS: RTRs, either acquired SARS-CoV-2 infection (infection group, n = 132) or were vaccinated with two vaccine doses (vaccination group, n = 78) against SARS-CoV-2, were recruited in the study. Thirty-five unvaccinated RTRs, without anti-SARS-CoV-2 spike protein-specific antibodies, were also included as control. Cytokines interleukine-6 (IL-6), interferon-γ (IFN-γ), TGF-ß, and IL-10 were measured using ELISA. The SARS-CoV-2 spike protein-specific IgG-titer was measured by chemiluminescent microparticle immunoassay methods. RESULTS: The seroconversion rate in the infection group was 115/132 (87.12%), with a median antibody titer 706.40 au/mL (IQR, 215.45-1844.42), and in the vaccination group was 63/78 (80.76%) with antibody titer 1454.20 au/mL (IQR, 80.52-3838.75). The IL-6, IFN-γ, TGF-ß, and IL-10 levels were significantly higher in both the infection and vaccination group compared to healthy control. In the infection group, pro-inflammatory cytokines IL-6 (55.41 ± 24.30 vs. 31.64 ± 16.98 pg/mL, p < .001) and IFN-γ (91.21 ± 33.09 vs. 61.69 ± 33.28 pg/mL, p = .001) were significantly higher in the seroconverter group as compared to non-seroconverter. Similarly, in the vaccination group, pro-inflammatory cytokines IL-6 (50.31 ± 25.67 vs. 30.00 ± 11.19 pg/mL; p = .002) and IFN-γ (65.70 ± 39.78 vs. 32.14 ± 17.48 pg/mL; p = .001) were significantly higher in the seroconverter group compared to non-seroconverter. In contrast, TGF-ß (820.96 ± 415.78 vs. 1045.57 ± 204.66; p = .046) was higher in non-seroconverter. CONCLUSIONS: Pro-inflammatory cytokines IL-6 and IFN-γ were significantly associated with seroconversion after SARS-CoV-2 infection and vaccination in RTRs.

Antibody response to ChAdOx1 nCoV-19 (Covishield®) vaccine in people on maintenance hemodialysis.

INTRODUCTION: People on renal replacement therapy (RRT) have a high risk of COVID-19 infection and subsequent death. COVID-19 vaccination is strongly recommended for those on RRT. Data are limited on the immune response of the ChAdOx1 nCoV-19/AZD1222 (Covishield®) vaccine in patients on RRT. METHODS: A prospective cohort of adult (age > 18 years), on RRT in the form of hemodialysis were included and received two intramuscular doses of Covishield®. A blood specimen of 5.0 mL was collected at two time points, within a few days before administering the first dose of the vaccine and at 4-16 weeks after the second dose. According to their prior COVID-19 infection status, the participants were grouped as (i) prior symptomatic COVID-19 infection, (ii) prior asymptomatic COVID-19 infection, and (iii) no prior COVID-19 infection. RESULTS: A large proportion (81%) of participants had anti-spike antibodies (ASAb) before vaccination, and a reasonable proportion (30%) also had neutralizing antibodies (NAb). The titer of ASAb was relatively low (207 U/mL) before vaccination. The ASAb titer (9405 [1635-25,000] U/mL) and percentage of NAb (96.4% [59.6-98.1%]) were markedly increased following the administration of two doses of the vaccine. The participants' prior COVID-19 exposure status did not influence the rise in ASAb titer and NAb percentage. Further, administering two doses of the Covishield vaccine helps them achieve a high ASAb titer. CONCLUSION: Two doses of ChAdOx1 nCoV-19/AZD1222 (Covishield®) vaccine, given 12 weeks apart, achieve a high titer of ASAb and a high percentage of NAb in people on hemodialysis.

Ligand-based designing of DPP-4 inhibitors via hybridization; synthesis, docking, and biological evaluation of pyridazine-acetohydrazides.

A series of novel pyridazine-acetohydrazide hybrids were designed, synthesized, and evaluated for their in vitro and in vivo antihyperglycemic activity. In this context, pyridazine-acetohydrazides (6a-6p) were synthesized by coupling substituted aldehyde with 2-(5-cyano-6-oxo-3,4-diphenylpyridazine-1-6H-yl) acetohydrazide, which was prepared via the reaction of pyridazine ester with hydrazine hydrate. The molecular docking study was carried out to examine the binding affinities and interaction of designed compounds against the DPP-4 enzyme. Compounds 6e, 6f, 6l, and 6n exhibited interaction with active residue. In silico ADMET properties, and toxicity studies corroborated that compounds were found to have good bioavailability and less toxic. The synthesized compounds were further estimated for in vitro DPP-4 activity. Compounds 6e and 6l were found as the most effective DPP-4 inhibitor in this series with IC50 values (6.48, 8.22 nM) when compared with sitagliptin (13.02 nM). According to the toxicity assay compound, 6l showed very less toxicity at a higher concentration so further selected for the in vivo antihyperglycemic activity.

Lower Circulating Cytotoxic T-Cell Frequency and Higher Intragraft Granzyme-B Expression Are Associated with Inflammatory Interstitial Fibrosis and Tubular Atrophy in Renal Allograft Recipients.

Background and Objectives: Inflammatory interstitial fibrosis and tubular atrophy (i-IFTA) is an inflammation in the area of tubular atrophy and fibrosis. i-IFTA is poorly associated with graft outcome and associated with infiltration of inflammatory mononuclear cells. A cytotoxic T cell is a granzyme B+CD8+CD3+ T cell, mainly secret granzyme B. Granzyme B is a serine protease that may mediate allograft injury and inflammatory interstitial fibrosis and tubular atrophy (i-IFTA). However, there is no report identifying the association of granzyme B with i-IFTA after a long post-transplant interval. Material and Methods: In this study, we have measured the cytotoxic T-cell frequency with flow cytometry, serum and PBMCs culture supernatants granzyme-B levels with ELISA and intragraft granzyme-B mRNA transcript expression with the RT-PCR in RTRs in 30 patients with biopsy-proven i-IFTA and 10 patients with stable graft function. Result: The frequency of cytotoxic T cells (CD3+CD8+ granzyme B+) in SGF vs. i-IFTA was (27.96 ± 4.86 vs. 23.19 ± 3.85%, p = 0.011), the serum granzyme-B level was (100.82 ± 22.41 vs. 130.32 ± 46.60, p = 0.038 pg/mL) and the intragraft granzyme-B mRNA transcript expression was (1.01 ± 0.048 vs. 2.10 ± 1.02, p < 0.001 fold). The frequency of CD3+ T cells in SGF vs. i-IFTA was (66.08 ± 6.8 vs. 65.18 ± 9.35%; p = 0.68) and that of CD3+CD8+ T cells was (37.29 ± 4.11 vs. 34.68 ± 5.43%; p = 0.28), which were similar between the 2 groups. CTLc frequency was negatively correlated with urine proteinuria (r = -0.51, p < 0.001), serum creatinine (r = -0.28, p = 0.007) and eGFR (r = -0.28, p = 0.037). Similarly, the PBMC culture supernatants granzyme-B level was negatively correlated with urine proteinuria (r = -0.37, p < 0.001) and serum creatinine (r = -0.31, p = 0.002), while the serum granzyme-B level (r = 0.343, p = 0.001) and intragraft granzyme-B mRNA transcript expression (r = 0.38, p < 0.001) were positively correlated with proteinuria. Conclusions: A decrease in the CTLc frequency in circulation and an increased serum granzyme-B level and intragraft granzyme-B mRNA expression shows that cytotoxic T cells may mediate the allograft injury in RTRs with i-IFTA by releasing granzyme B in serum and intragraft tissue.

Interplay mechanisms between progesterone and endocannabinoid receptors in regulating bull sperm capacitation and acrosome reaction.

After ejaculation, sperm show a limited capacity for transcription and translation. In the oviduct, most of the signalling in sperm is nongenomic and is mediated through membrane receptors. Studies have shown that the cation channel of sperm (CatSper), cAMP, cGMP, protein kinases, and tyrosine phosphorylation are involved in the nongenomic signalling of progesterone (P4) in sperm. However, it is not known whether there is an interplay between P4 and cannabinoid receptors 1 and 2 (CB1 and CB2), transient receptor potential vanilloid 1 (TRPV1), CatSper channels, cAMP, inositol trisphosphate receptor (IP3R), and mitogen-activated protein kinase (MAPK); these potential regulators are involved in the regulation of capacitation and the acrosome reaction. In the present study, selective blockers of CB1, CB2, TRPV1, CatSper channels, cAMP, protein kinase A (PKA), IP3R, and MAPK were used to identify their involvement in P4-mediated bull sperm capacitation and the acrosome reaction. Selective blocking of any one of the molecules caused a significant reduction in P4 signalling (p < 0.05). Interestingly, blocking these molecules in combination followed by treatment with P4 resulted in the complete absence of capacitation and the acrosome reaction. Blocking a single receptor was not able to eliminate the P4-induced capacitation and the acrosome reaction. In addition to the CB1 and CB2 receptors, there may be other signalling pathways that mediate P4 signalling. In conclusion, P4 signalling exhibited interplay with the cannabinoid receptors. The regulation of sperm capacitation and the acrosome reaction also involved cAMP, PKA, l-type and T-type calcium channels, TRPV1, inositol trisphosphate, and MAPK.

Crosstalk between gut microbiota and lung inflammation in murine toxicity models of respiratory exposure or co-exposure to carbon nanotube particles and cigarette smoke extract.

Carbon nanotubes (CNTs) are emerging environmental and occupational toxicants known to induce lung immunotoxicity. While the underlying mechanisms are evolving, it is yet unknown whether inhaled CNTs would cause abnormalities in gut microbiota (dysbiosis), and if such microbiota alteration plays a role in the modulation of CNT-induced lung immunotoxicity. It is also unknown whether co-exposure to tobacco smoke will modulate CNT effects. We compared the effects of lung exposure to multi-wall CNT, cigarette smoke extract (CSE), and their combination (CNT + CSE) in a 4-week chronic toxicity mouse model. The exposures induced differential perturbations in gut microbiome as evidenced by altered microbial α- and ß- diversity, indicating a lung-to-gut communication. The gut dysbiosis due to CNTs, unlike CSE, was characterized by an increase in Firmicutes/Bacteroidetes ratio typically associated with proinflammatory condition. Notably, while all three exposures reduced Proteobacteria, the CNT exposure and co-exposure induced appearance of Tenericutes and Cyanobacteria, respectively, implicating them as potential biomarkers of exposure. CNTs differentially induced certain lung proinflammatory mediators (TNF-α, IL-1ß, CCL2, CXCL5) whereas CNTs and CSE commonly induced other mediators (CXCL1 and TGF-ß). The co-exposure showed either a component-dominant effect or a summative effect for both dysbiosis and lung inflammation. Depletion of gut microbiota attenuated both the differentially-induced and commonly-induced (TGF-ß) lung inflammatory mediators as well as granulomas indicating gut-to-lung communication and a modulatory role of gut dysbiosis. Taken together, the results demonstrated gut dysbiosis as a systemic effect of inhaled CNTs and provided the first evidence of a bidirectional gut-lung crosstalk modulating CNT lung immunotoxicity.

Click inspired novel pyrazole-triazole-persulfonimide & pyrazole-triazole-aryl derivatives; Design, synthesis, DPP-4 inhibitor with potential anti-diabetic agents.

This work presented the first report on designing, synthesizing of novel pyrazole-triazole-persulfonimide (7a-i) and pyrazole-triazole-aryl derivatives (8a-j) via click reaction using CuI catalyst and evaluated for their anti-diabetic activity and DPP-4 inhibitory effect. Click reactions went smoothly with CuI catalyst in the presence of tridentate chelating ligands and produced copper-free target pyrazole-triazole-persulfonimide analogues in excellent yield at RT. The designed compounds were docked against DPP-4 enzyme and showed excellent interaction with active amino acids residue. Further, all novel pyrazole-triazole-persulfonimide and pyrazole-triazole derivatives were subjected to enzyme-based in vitro DPP-4 inhibitory activity. Based on the SAR study DPP-4 inhibitory capacity compounds 7f (9.52 nM) and 8h (4.54 nM) possessed the significant inhibition of DPP-4. Finally compounds 7f and 8h were evaluated for their in vivo anti-diabetic activity using STZ induced diabetic mice model, and 8h showed a significant diabetic control effect compared to the sitagliptin drug. These studies demonstrated that the novel pyrazole-triazole-persulfonimide and pyrazole-triazole-aryl derivatives might be used as the leading compounds to develop novel DPP-4 inhibitors as potential anti-diabetic agents.

Computational Analysis Reveals Monomethylated Triazolopyrimidine as a Novel Inhibitor of SARS-CoV-2 RNA-Dependent RNA Polymerase (RdRp).

The human population is still facing appalling conditions due to several outbreaks of Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) virus. The absence of specific drugs, appropriate vaccines for mutants, and knowledge of potential therapeutic agents makes this situation more difficult. Several 1, 2, 4-triazolo [1, 5-a] pyrimidine (TP)-derivative compounds were comprehensively studied for antiviral activities against RNA polymerase of HIV, HCV, and influenza viruses, and showed immense pharmacological interest. Therefore, TP-derivative compounds can be repurposed against the RNA-dependent RNA polymerase (RdRp) protein of SARS-CoV-2. In this study, a meta-analysis was performed to ensure the genomic variability and stability of the SARS-CoV-2 RdRp protein. The molecular docking of natural and synthetic TP compounds to RdRp and molecular dynamic (MD) simulations were performed to analyse the dynamic behaviour of TP compounds at the active site of the RdRp protein. TP compounds were also docked against other non-structural proteins (NSP1, NSP2, NSP3, NSP5, NSP8, NSP13, and NSP15) of SARS-CoV-2. Furthermore, the inhibition potential of TP compounds was compared with Remdesivir and Favipiravir drugs as a positive control. Additionally, TP compounds were analysed for inhibitory activity against SARS-CoV RdRp protein. This study demonstrates that TP analogues (monomethylated triazolopyrimidine and essramycin) represent potential lead molecules for designing an effective inhibitor to control viral replication. Furthermore, in vitro and in vivo studies will strengthen the use of these inhibitors as suitable drug candidates against SARS-CoV-2.

MMP-7 derived peptides with MHC class-I binding motifs from canine mammary tumor tissue elicit strong antigen-specific T-cell responses in BALB/c mice.

Matrix Metalloproteinases (MMPs)-induced altered proteolysis of extracellular matrix proteins and basement membrane holds the key for tumor progression and metastasis. Matrix metalloproteinases-7 (Matrilysin), the smallest member of the MMP family also performs quite alike; thus serves as a potential candidate for anti-tumor immunotherapy. Conversely, being an endogenous tumor-associated antigen (TAA), targeting MMP-7 for immunization is challenging. But MMP-7-based xenovaccine can surmount the obstacle of poor immunogenicity and immunological tolerance, often encountered in TAA-based conventional vaccine for anti-tumor immunotherapy. This paves the way for investigating the potential of MMP-7-derived major histocompatibility complex (MHC)-binding peptides to elicit precise epitope-specific T-cell responses towards their possible inclusion in anti-tumor vaccine formulations. Perhaps it also ushers the path of achieving multiple epitope-based broad and universal cellular immunity. In current experiment, an immunoinformatics approach has been employed to identify the putative canine matrix matelloproteinases-7 (cMMP-7)-derived peptides with MHC class-I-binding motifs which can elicit potent antigen-specific immune responses in BALB/c mice. Immunization with the cMMP-7 DNA vaccine induced a strong CD8+ cytotoxic T lymphocytes (CTLs) and Th1- type response, with high level of gamma interferon (IFN-γ) production in BALB/c mice. The two identified putative MHC-I-binding nonameric peptides (Peptide32-40 and Peptide175-183) from cMMP-7 induced significant lymphocyte proliferation along with the production of IFN-γ from CD8+ T-cells in mice immunized with cMMP-7 DNA vaccine. The current observation has depicted the immunogenic potential of the two cMMP-7-derived nonapeptides for their possible exploitation in xenovaccine-mediated anti-tumor immunotherapy in mouse model.

Fetal brain tissue characterization at 1.5 T using STrategically Acquired Gradient Echo (STAGE) imaging.

OBJECTIVES: To estimate human fetal brain MRI tissue properties including apparent T1 (T1app) and apparent proton density (PDapp) by using a rapid multi-contrast acquisition protocol called STrategically Acquired Gradient Echo (STAGE) imaging. METHODS: STAGE data were collected using two flip angles (15° and 60°, with a TR = 600 ms) for 30 pregnant women at 1.5 T (15 healthy controls: gestational age (GA) range 19 + 1/7 weeks to 34 + 5/7 weeks; 11 abnormal subjects with ventriculomegaly: GA range 21 + 5/7 weeks to 31 + 5/7 weeks; 4 subjects with other abnormalities). Both T1app and PDapp maps of the fetal brain were calculated from the STAGE data. A region-of-interest-based approach was used to measure T1app and PDapp in the subplate/intermediate zone (SP/IZ), cortical plate (CP), and cerebrospinal fluid (CSF) in the fetal brain. RESULTS: The ratios of T1appSP/IZ/T1appCP and PDappSP/IZ/PDappCP were larger than unity while T1appSP/IZ/T1appCSF and PDappSP/IZ/PDappCSF were both less than unity. CONCLUSIONS: STAGE imaging provides a potential practical approach to estimate multi-parametric properties of the human fetal brain. KEY POINTS: • STAGE is feasible in measuring fetal brain tissue properties. • Water content in cortical plate and subplate/intermediate zone approaches that of cerebrospinal fluid in early gestational ages.

A novel monopartite begomovirus and satellites associated with yellow mosaic disease of Sida spp. in India.

Begomoviruses (family Geminiviridae) cause severe diseases in many economically important crops and non-cultivated plants in the warmer regions of the world. Non-cultivated weeds have been reported to act as natural virus reservoirs. In January 2016, Sida plants with yellow mosaic symptoms were found at the edge of an agricultural field in Gujarat, India. Sequence analysis of the viral genomic components cloned from a diseased Sida plant indicated the presence of a distinct monopartite begomovirus (proposed as sida yellow mosaic Gujarat virus) along with a betasatellite (ludwigia leaf distortion betasatellite) and an alphasatellite (malvastrum yellow mosaic alphasatellite). Our results emphasize that this weed may harbor a begomovirus-alphasatellite-betasatellite complex. This host serves as a potential source of virus inoculum, which can be transmitted by whiteflies to other cultivated crops.

Floodplains landforms, clay deposition and irrigation return flow govern arsenic occurrence, prevalence and mobilization: A geochemical and isotopic study of the mid-Gangetic floodplains.

This article attempts to understand the evolution of groundwater chemistry in the mid Gangetic floodplain through the identification of hydrogeochemical processes including the impact of surface recharge and geological features. Isotopic investigations identified that irrigation return flow is partly responsible for arsenic (As) enrichment through preferential vertical recharge. Further, the floodplain geomorphological attributes and associated As hydrogeochemical behaviour traced through isotopes tracers highlighted that meandering and ox-bow like geomorphological features owing to clay deposition leads to the anoxic condition induced reductive microbial dissolution of As-bearing minerals causing the arsenic contamination in the investigated aquifer of the mid-Gangetic plain (MGP). To achieve the objectives, 146 water samples for water chemistry and 62 samples for the isotopic study were collected from Bhojpur district, Bihar (district bounded by the river Ganges in the north and Son in the east) located in MGP during the pre-monsoon season of 2018. The chemical results revealed high arsenic concentration (BDL to 206 µg.L-1, 32% samples are exceeding the 10 µg.L-1 limit) in the Holocene recent alluviums which are characterized by various geomorphological features such as meander scars and oxbow lake (northern part of the district). Arsenic is more concentrated in the depth range of 15-40 m below ground surface. All other trace metals viz. Ni, Pb, Zn, Cd and Al were found in low concentration except Fe and Mn. The geochemical analyses suggest that rock-water interaction is controlling the hydro-geochemistry while the chemical constituent of the groundwater is mainly controlled by carbonate weathering with limited contribution from silicate weathering. The isotopic signatures revealed that the Son river is recharging groundwater while the groundwater is contributing to the Ganges river. A clear pattern of fast vertical recharge in the arsenic contaminated area is observed in the proximity to the river Ganges with an elevated nitrate concentration resulted from the reduced As dissolution. The origin of groundwater is local precipitation with low to high evaporation enrichment effect which is further indicating the vertical mixing of groundwater from the irrigation return flow and/or recharge from domestic discharge causing enhanced As mobilization through microbial assisted reductive dissolution of As-bearing minerals.

Bhendi Yellow Vein Mosaic Virus and Bhendi Yellow Vein Mosaic Betasatellite Cause Enation Leaf Curl Disease and Alter Host Phytochemical Contents in Okra.

Whitefly (Bemisia tabaci)-transmitted begomoviruses cause severe diseases in numerous economically important dicotyledonous plants. Okra enation leaf curl disease (OELCuD) has emerged as a serious threat to okra (Abelmoschus esculentus L. Moench) cultivation in the Indian subcontinent. This study reports the association of a monopartite begomovirus (bhendi yellow vein mosaic virus; BYVMV) and betasatellite (bhendi yellow vein mosaic betasatellite; BYVB) with OELCuD in the Mau region of Uttar Pradesh, India. The BYVMV alone inoculated Nicotiana benthamiana and A. esculentus cv. Pusa Sawani plants developed mild symptoms. Co-inoculation of BYVMV and BYVB resulted in a reduced incubation period, an increased symptom severity, and an enhanced BYVMV accumulation by Southern hybridization and quantitative real-time PCR. This is the first study that satisfies Koch's postulates for OELCuD in its natural host. Activities of various antioxidative enzymes were significantly increased in the virus-inoculated okra plants. Differential responses in various biochemical components (such as photosynthetic pigments, phenol, proline, and sugar) in diseased okra plants were observed. This change in phytochemical responses is significant in understanding its impact on virus pathogenesis and disease development.

Soil PAHs contamination effect on the cellular and subcellular organelle changes of Phragmites australis Cav.

The concentrations of ∑16 priority polycyclic aromatic hydrocarbons (PAHs) for soils, roots, and above-ground parts of reed (Phragmites australis Cav.) were determined on different monitoring plots located near the city of Kamensk-Shakhtinsky, southern Russia, where historically received industrial sewage and sludge. The total PAHs concentration in monitoring soil plots was significantly higher than those in the background site which situated at the distance of 2 km from the contamination source. Accordingly, the maximum accumulation was found for phenanthrene and chrysene among the 16 priority PAHs in most of the plant samples collected in the impact zone. The effects of PAHs' pollution on changes of Phragmites australis Cav. cellular and subcellular organelles in the studied monitoring sites were also determined using optical and electron microscopy, respectively. The obtained data showed that increasing of PAHs contamination negatively affected the ultrastructural changes of the studied plants. Phragmites australis Cav. showed a high level of adaptation to the effect of stressors by using tissue and cell levels. In general, the detected alterations under the PAHs effect were possibly connected to changes in biochemical and histochemical parameters as a response for reactive oxygen species and as a protective response against oxidative stress. The obtained results introduce innovative findings of cellular and subcellular changes in plants exposed to ∑16 priority PAHs as very persistent and toxic contaminants.

The dynamic responses of plant physiology and metabolism during environmental stress progression.

At adverse environmental conditions, plants produce various kinds of primary and secondary metabolites to protect themselves. Both primary and secondary metabolites play a significant role during the heat, drought, salinity, genotoxic and cold conditions. A multigene response is activated during the progression of these stresses in the plants which stimulate changes in various signaling molecules, amino acids, proteins, primary and secondary metabolites. Plant metabolism is perturbed because of either the inhibition of metabolic enzymes, shortage of substrates, excess demand for specific compounds or a combination of these factors. In this review, we aim to present how plants synthesize different kinds of natural products during the perception of various abiotic stresses. We also discuss how time-scale variable stresses influence secondary metabolite profiles, could be used as a stress marker in plants. This article has the potential to get the attention of researchers working in the area of quantitative trait locus mapping using metabolites as well as metabolomics genome-wide association.

Dual-Imaging Modality Approach to Evaluate Cerebral Hemodynamics in Growth-Restricted Fetuses: Oxygenation and Perfusion.

OBJECTIVE: To evaluate a dual-imaging modality approach to obtain a combined estimation of venous blood oxygenation (SνO2) using susceptibility-weighted magnetic resonance imaging (SWI-MRI), and blood perfusion using power Dopp-ler ultrasound (PDU) and fractional moving blood volume (FMBV) in the brain of normal growth and growth-restricted fetuses. METHODS: Normal growth (n = 33) and growth-restricted fetuses (n = 10) from singleton pregnancies between 20 and 40 weeks of gestation were evaluated. MRI was performed and SνO2 was calculated using SWI-MRI data obtained in the straight section of the superior sagittal sinus. Blood perfusion was estimated using PDU and FMBV from the frontal lobe in a mid-sagittal plane of the fetal brain. The association between fetal brain SνO2 and FMBV, and the distribution of SνO2 and FMBV values across gestation were calculated for both groups. RESULTS: In growth-restricted fetuses, the brain SνO2 values were similar, and the FMBV values were higher across gestation as compared to normal growth fetuses. There was a significantly positive association between SνO2 and FMBV values (slope = 0.38 ± 0.12; r = 0.7; p = 0.02) in growth-restricted fetuses. In normal growth fetuses, SνO2 showed a mild decreasing trend (slope = -0.7 ± 0.4; p = 0.1), whereas FMBV showed a mild increasing trend (slope = 0.2 ± 0.2; p = 0.2) with advancing gestation, and a mild but significant negative association (slope = -0.78 ± 0.3; r = -0.4; p = 0.04) between these two estimates. CONCLUSION: Combined MRI (SWI) and ultrasound (FMBV) techniques showed a significant association between cerebral blood oxygenation and blood perfusion in normal growth and growth-restricted fetuses. This dual-imaging approach could contribute to the early detection of fetal "brain sparing" and brain oxygen saturation changes in high-risk pregnancies.

Accumulation and transformation of benzo[a]pyrene in Haplic Chernozem under artificial contamination.

Polycyclic aromatic hydrocarbons (PAHs) have been a major concern because of their carcinogenicity, mutagenicity, teratogenicity and wide distribution in the environment. Over 90% of PAHs in the environment exist on soil surface/sediment. Benzo[a]pyrene (BaP) is one of the predominant PAHs in soil. Thus, it is critically important to understand the patterns of BaP accumulation and transformation peculiarities in soil for the risk assessment. The studies were conducted in model experiment with Haplic Chernozem spiked with various doses of BaP (20, 200, 400 and 800 µg kg-1) equivalent to 1, 10, 20 and 40 levels of maximum permissible concentrations. The unique properties of Haplic Chernozem were studied allow to accumulate and transform BaP as well as barley plants ability to absorb of some BaP concentration. Extraction of BaP from the soil was carried out by the saponification method. The qualitative and quantitative determination of BaP and other polycyclic aromatic hydrocarbons (PAHs) was performed by high-performance liquid chromatography with fluorescence detection (Agilent 1260 Germany, 2014). BaP accumulation in soil depended on the applied BaP concentrations in Haplic Chernozem. Studying the features of PAHs transformation in the soil of a model experiment 1 year after the compound application showed the BaP content in the soil decreased up to 11-40%. Two years after the BaP application the content in the soil decreased up to 15-44% from the initial BaP content in the soil. The percentage of BaP concentration reduction in Haplic Chernozem increased with an increase in the dose of the applied xenobiotic. An increase in the dose of the applied pollutant to the soil of the model experiment contributed to an increase in all PAHs, which indicated a rapid BaP transformation in Haplic Chernozem. The PAHs content in the soils of model experiment in the first year of the research formed the following descending series: pyrene > chrysene > fluoranthene > phenanthrene. In the second year of research the phenanthrene content became higher than the fluoranthene content. The content of these compounds exceeded 20% of the total PAHs content in the soil samples in the first and second years of the model experiment. The features of PAHs accumulation and transformation in soils under artificial pollution showed the degradation of large-nuclear PAHs, starting from 5-ring polyarenes, and their structural reorganization into the less-nuclear polyarenes, such as 4-, 3-, and 2-ring PAHs. During the 2 years of the model experiment the BaP concentration in the soil decreased up to 15-44% from the initial BaP content in the soil.