167 research outputs found
Can chilling tolerance of C4 photosynthesis in \u3ci\u3eMiscanthus\u3c/i\u3e be transferred to sugarcane?
The goal of this study was to investigate whether chilling tolerance of C4 photosynthesis in Miscanthus can be transferred to sugarcane by hybridization. Net leaf CO2 uptake (Asat) and the maximum operating efficiency of photosystem II (Đ€PSII) were measured in warm conditions (25 °C/20 °C), and then during and following a chilling treatment of 10 °C/5 °C for 11 day in controlled environment chambers. Two of three hybrids (miscanes), âUS 84-1058â and âUS 87-1019â, did not differ significantly from the chilling tolerant M. xgiganteus âIllinoisâ (Mxg), for Asat, and ΊPSII measured during chilling. For Mxg grown at 10 °C/5 °C for 11 days, Asat was 4.4 ÎŒmol m-2 s-1, while for miscane âUS 84-1058â and âUS 87-1019â, Asat was 5.7 and 3.5 ÎŒmol m-2 s-1, respectively. Miscanes âUS 84-1058â and âUS 87-1019â and Mxg had significantly higher rates of Asat during chilling than three tested sugarcanes. A third miscane showed lower rates than Mxg during chilling, but recovered to higher rates than sugarcane upon return to warm conditions. Chilling tolerance of âUS 84-1058â was further confirmed under autumn field conditions in southern Illinois. The selected chilling tolerant miscanes have particular value for biomass feedstock and biofuel production and at the same time they can be a starting point for extending sugarcaneâs range to colder climates
Blocking c-MET/ERBB1 Axis Prevents Brain Metastasis in ERBB2+ Breast Cancer
Brain metastasis (BrM) remains a significant cause of cancer-related mortality in epidermal growth factor receptor 2-positive (ERBB2+) breast cancer (BC) patients. We proposed here that a combination treatment of irreversible tyrosine kinase inhibitor neratinib (NER) and the c-MET inhibitor cabozantinib (CBZ) could prevent brain metastasis. To address this, we first tested the combination treatment of NER and CBZ in the brain-seeking ERBB2+ cell lines SKBrM3 and JIMT-1-BR3, and in ERBB2+ organoids that expressed the c-MET/ERBB1 axis. Next, we developed and characterized an orthotopic mouse model of spontaneous BrM and evaluated the therapeutic effect of CBZ and NER in vivo. The combination treatment of NER and CBZ significantly inhibited proliferation and migration in ERBB2+ cell lines and reduced the organoid growth in vitro. Mechanistically, the combination treatment of NER and CBZ substantially inhibited ERK activation downstream of the c-MET/ERBB1 axis. Orthotopically implanted SKBrM3+ cells formed primary tumor in the mammary fat pad and spontaneously metastasized to the brain and other distant organs. Combination treatment with NER and CBZ inhibited primary tumor growth and predominantly prevented BrM. In conclusion, the orthotopic model of spontaneous BrM is clinically relevant, and the combination therapy of NER and CBZ might be a useful approach to prevent BrM in BC
Effect of pinning and driving force on the metastability effects in weakly pinned superconductors and the determination of spinodal line pertaining to order-disorder transition
We explore the effect of varying drive on metastability features exhibited by
the vortex matter in single crystals of 2H-NbSe and CeRu with varying
degree of random pinning. An optimal balance between the pinning and driving
force is needed to view the metastability effects in typically weakly pinned
specimen of low temperature superconductors. As one uses samples with larger
pinning in order to differentiate the response of different metastable vortex
states, one encounters a new phenomena, viz., the second magnetization peak
(SMP) anomaly prior to the PE. Interplay between the path dependence in the
critical current density and the non-linearity in the electromagnetic response
determine the metastability effects seen in first and the third harmonic
response of the ac susceptibility across the temperature regions of the SMP and
the PE. The limiting temperature above which metastability effects cease can be
conveniently located in the third harmonic data, and the observed behavior can
be rationalized within the Beans Critical State model. A vortex phase diagram
showing the different vortex phases for a typically weakly pinned specimen has
been constructed via the ac susceptibility data in a crystal of 2H-NbSe
which shows the SMP and the PE anomalies. The phase space of coexisting weaker
and stronger pinned regions has been identified. It can be bifurcated into two
parts, where the order and disorder dominate, respectively. The former part
continuously connects to the reentrant disordered vortex phase pertaining to
the small bundle pinning regime, where the vortices are far apart, interaction
effects are weak and the polycrystalline form of flux line lattice prevails.Comment: Submitted to the Special Volume on Vortex State Studies, Pramana J.
Phy
Traumatic fracture of central venous catheter resulting in potential migration of distal fragment: a case report
We report a surgical retrieval of an indwelling portion of a traumatic rupture of the Central venous catheter following hair cutting by a confused patient secondary to Postoperative cognitive dysfunction. He had a dynamic compression screw for fixation of fractured neck of femur after previously failed surgical procedure. The second procedure was complicated with major blood loss, which required central venous and arterial line insertion for intra-operative and post-operative management. The patient was discharged to the ward following an uneventful stay on intensive care. While on the ward, he decided to trim his hair and in the process he inadvertently cut through the right internal jugular catheter. Complications and management resulting from embolisation of central line are reviewed
Disruption of FDPS/Rac1 Axis Radiosensitizes Pancreatic Ductal Adenocarcinoma by Attenuating DNA Damage Response and Immunosuppressive Signalling
BACKGROUND: Radiation therapy (RT) has a suboptimal effect in patients with pancreatic ductal adenocarcinoma (PDAC) due to intrinsic and acquired radioresistance (RR). Comprehensive bioinformatics and microarray analysis revealed that cholesterol biosynthesis (CBS) is involved in the RR of PDAC. We now tested the inhibition of the CBS pathway enzyme, farnesyl diphosphate synthase (FDPS), by zoledronic acid (Zol) to enhance radiation and activate immune cells.
METHODS: We investigated the role of FDPS in PDAC RR using the following methods: in vitro cell-based assay, immunohistochemistry, immunofluorescence, immunoblot, cell-based cholesterol assay, RNA sequencing, tumouroids (KPC-murine and PDAC patient-derived), orthotopic models, and PDAC patient\u27s clinical study.
FINDINGS: FDPS overexpression in PDAC tissues and cells (P \u3c 0.01 and P \u3c 0.05) is associated with poor RT response and survival (P = 0.024). CRISPR/Cas9 and pharmacological inhibition (Zol) of FDPS in human and mouse syngeneic PDAC cells in conjunction with RT conferred higher PDAC radiosensitivity in vitro (P \u3c 0.05, P \u3c 0.01, and P \u3c 0.001) and in vivo (P \u3c 0.05). Interestingly, murine (P = 0.01) and human (P = 0.0159) tumouroids treated with Zol+RT showed a significant growth reduction. Mechanistically, RNA-Seq analysis of the PDAC xenografts and patients-PBMCs revealed that Zol exerts radiosensitization by affecting Rac1 and Rho prenylation, thereby modulating DNA damage and radiation response signalling along with improved systemic immune cells activation. An ongoing phase I/II trial (NCT03073785) showed improved failure-free survival (FFS), enhanced immune cell activation, and decreased microenvironment-related genes upon Zol+RT treatment.
INTERPRETATION: Our findings suggest that FDPS is a novel radiosensitization target for PDAC therapy. This study also provides a rationale to utilize Zol as a potential radiosensitizer and as an immunomodulator in PDAC and other cancers.
FUNDING: National Institutes of Health (P50, P01, and R01)
Osjetljiva spektrofotometrijska metoda za odreÄivanje sulfonamida u farmaceutskim pripravcima
A new, simple and sensitive spectrophotometric method for the determination of some sulfonamide drugs has been developed. The method is based on the diazotisation of sulfacetamide, sulfadiazine, sulfaguanidine, sulfamerazine, sulfamethazine, sulfamethoxazole and coupling with 8-hydroxyquinoline in alkaline media to yield red coloured products, with absorption maximum at 500 nm. The Beerâs law is obeyed from 0.17.0 ”g mL1. The limits of quantification and limits of detection were 0.110.18 and 0.030.5 ”g mL1, respectively. Intraday precision (RSD 0.10.5%) and accuracy (recovery 97.3100.8) of the developed method were evaluated. No interference was observed from common adjuvants. The method has been successfully applied to the assay of sulpha drug in the pharmaceutical formulations.U radu je opisana nova, jednostavna i osjetljiva spektrofotometrijska metoda za odreÄivanje sulfonamida. Metoda se temelji na prevoÄenju sulfacetamida, sulfadiazina, sulfagvanidina, sulfamerazina, sulfometazina i sulfametoksazola u diazoderivate koji kondenzacijom s 8-hidroksikinolinom u alkalnom mediju daju crveno obojene produkte s maksimumom apsorpcije pri 500 nm. Beerov zakon vrijedi u koncentracijskom rasponu 0,17,0 ”g mL1. Granice kvantifikacije i granice detekcije su 0,11-0,18, odnosno 0,03-0,05 ”g mL-1. Za predloĆŸenu metodu procijenjene su intermedirska preciznost (RSD 0.1-0,5%) i toÄnost (analitiÄki povrat 97,3-100,8). UobiÄanjene pomoÄne tvari u tabletama ne interferiraju tijekom odreÄivanja. Metoda je uspjeĆĄno primijenjena za analizu sulfonamida u farmaceutskim pripravcima
Long non-coding RNA-mediated epigenetic response for abiotic stress tolerance in plants
Plants perceive environmental fluctuations as stress and confront several stresses throughout their life cycle individually or in combination. Plants have evolved their sensing and signaling mechanisms to perceive and respond to a variety of stresses. Epigenetic regulation plays a critical role in the regulation of genes, spatiotemporal expression of genes under stress conditions and imparts a stress memory to encounter future stress responses. It is quintessential to integrate our understanding of genetics and epigenetics to maintain plant fitness, achieve desired genetic gains with no trade-offs, and durable long-term stress tolerance. The long non-coding RNA >200 nts having no coding potential (or very low) play several roles in epigenetic memory, contributing to the regulation of gene expression and the maintenance of cellular identity which include chromatin remodeling, imprinting (dosage compensation), stable silencing, facilitating nuclear organization, regulation of enhancer-promoter interactions, response to environmental signals and epigenetic switching. The lncRNAs are involved in a myriad of stress responses by activation or repression of target genes and hence are potential candidates for deploying in climate-resilient breeding programs. This review puts forward the significant roles of long non-coding RNA as an epigenetic response during abiotic stresses in plants and the prospects of deploying lncRNAs for designing climate-resilient plants
The Ninth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the SDSS-III Baryon Oscillation Spectroscopic Survey
The Sloan Digital Sky Survey III (SDSS-III) presents the first spectroscopic
data from the Baryon Oscillation Spectroscopic Survey (BOSS). This ninth data
release (DR9) of the SDSS project includes 535,995 new galaxy spectra (median
z=0.52), 102,100 new quasar spectra (median z=2.32), and 90,897 new stellar
spectra, along with the data presented in previous data releases. These spectra
were obtained with the new BOSS spectrograph and were taken between 2009
December and 2011 July. In addition, the stellar parameters pipeline, which
determines radial velocities, surface temperatures, surface gravities, and
metallicities of stars, has been updated and refined with improvements in
temperature estimates for stars with T_eff<5000 K and in metallicity estimates
for stars with [Fe/H]>-0.5. DR9 includes new stellar parameters for all stars
presented in DR8, including stars from SDSS-I and II, as well as those observed
as part of the SDSS-III Sloan Extension for Galactic Understanding and
Exploration-2 (SEGUE-2).
The astrometry error introduced in the DR8 imaging catalogs has been
corrected in the DR9 data products. The next data release for SDSS-III will be
in Summer 2013, which will present the first data from the Apache Point
Observatory Galactic Evolution Experiment (APOGEE) along with another year of
data from BOSS, followed by the final SDSS-III data release in December 2014.Comment: 9 figures; 2 tables. Submitted to ApJS. DR9 is available at
http://www.sdss3.org/dr
Mechanistic Insights into a Novel Exporter-Importer System of Mycobacterium tuberculosis Unravel Its Role in Trafficking of Iron
Elucidation of the basic mechanistic and biochemical principles underlying siderophore mediated iron uptake in mycobacteria is crucial for targeting this principal survival strategy vis-Ă -vis virulence determinants of the pathogen. Although, an understanding of siderophore biosynthesis is known, the mechanism of their secretion and uptake still remains elusive.Here, we demonstrate an interplay among three iron regulated Mycobacterium tuberculosis (M.tb) proteins, namely, Rv1348 (IrtA), Rv1349 (IrtB) and Rv2895c in export and import of M.tb siderophores across the membrane and the consequent iron uptake. IrtA, interestingly, has a fused N-terminal substrate binding domain (SBD), representing an atypical subset of ABC transporters, unlike IrtB that harbors only the permease and ATPase domain. SBD selectively binds to non-ferrated siderophores whereas Rv2895c exhibits relatively higher affinity towards ferrated siderophores. An interaction between the permease domain of IrtB and Rv2895c is evident from GST pull-down assay. In vitro liposome reconstitution experiments further demonstrate that IrtA is indeed a siderophore exporter and the two-component IrtB-Rv2895c system is an importer of ferrated siderophores. Knockout of msmeg_6554, the irtA homologue in Mycobacterium smegmatis, resulted in an impaired M.tb siderophore export that is restored upon complementation with M.tb irtA.Our data suggest the interplay of three proteins, namely IrtA, IrtB and Rv2895c in synergizing the balance of siderophores and thus iron inside the mycobacterial cell
Earthworm Grazed-Trichoderma harzianum Biofortified Spent Mushroom Substrates Modulate Accumulation of Natural Antioxidants and Bio-Fortification of Mineral Nutrients in Tomato
The present investigation was aimed at evaluating the impact of earthworm grazed and Trichoderma harzianum biofortified spent mushroom substrate (SMS) on natural antioxidant and nutritional properties of tomato. Results of the investigation reveal that earthworm grazing and T. harzianum bio-fortification led to significant improvement in the physico-chemical properties of fresh SMS and its application increased the accumulation of natural antioxidants and mineral content in tomato as compared to either T. harzianum biofortified SMS or fresh SMS. In particular, the earthworm grazed, T. harzianum biofortified SMS (EGTHB-SMS) was found to inhibit lipid peroxidation and protein oxidation with significant increase in total polyphenol and flavonoid content in tomato. Further, it increased Fe2+/Fe3+ chelating activity, superoxide anion radical scavenging activity compared to other treatments. The results thus suggest an augmented elicitation of natural antioxidant properties in tomato treated with EGTHB-SMS, resulting in a higher radical scavenging activity, that is highly desirable for human health. In addition, the use of SMS to enhance the nutritional value of tomato fruits becomes an environment friendly approach in sustainable crop production
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