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Since the demonstration of p-type gallium nitride (GaN) through doping with substitutional magnesium (Mg) atoms1,2, rapid and comprehensive developments, such as blue light-emitting diodes, have considerably shaped our modern lives and contributed to a more carbon-neutral society3-5. However, the details of the interplay between GaN and Mg have remained largely unknown6-11. Here we observe that Mg-intercalated GaN superlattices can form spontaneously by annealing a metallic Mg film on GaN at atmospheric pressure. To our knowledge, this marks the first instance of a two-dimensional metal intercalated into a bulk semiconductor, with each Mg monolayer being intricately inserted between several monolayers of hexagonal GaN. Characterized as an interstitial intercalation, this process induces substantial uniaxial compressive strain perpendicular to the interstitial layers. Consequently, the GaN layers in the Mg-intercalated GaN superlattices exhibit an exceptional elastic strain exceeding -10% (equivalent to a stress of more than 20 GPa), among the highest recorded for thin-film materials12. The strain alters the electronic band structure and greatly enhances hole transport along the compression direction. Furthermore, the Mg sheets induce a unique periodic transition in GaN polarity, generating polarization-field-induced net charges. These characteristics offer fresh insights into semiconductor doping and conductivity enhancement, as well as into elastic strain engineering of nanomaterials and metal-semiconductor superlattices13.
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A double regioselective cycloaddition reaction of 1,3-diynes with azide is reported to synthesize fully substituted 5-alkynyl-1,2,3-triazoles without any catalyst, metal, or other factor. Computational studies revealed that the 5-alkynyl-1,2,3-triazole derivative is both kinetically and thermodynamically favorable irrespective of the nature of the substituents at the alkyne termini in 1,3-diynes. The simplicity of the reaction, extremely high regioselectivity under metal-free conditions, wide substrate scope, and good to excellent yields might inspire further studies of the cycloaddition of 1,3-diynes in addition to click chemistry.
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Quantum chemical calculations are performed to explore all of the possible pathways for primary ozonide (POZ) formation from gas-phase ozonolysis of catechol. Canonical transition state theory has been used to calculate the rate coefficients of individual steps for the formation of POZ. The calculated rate coefficients for 1,3-cycloaddition of ozone at the (i) unsaturated C(OH)âC(OH) bond and (ii) CHâC(OH) of catechol, respectively, are in good agreement with the experimental rate constant. In general, subsequent decomposition of POZ leads to well-known Criegee Intermediates. This work reveals a parallel pathway by which the endo-addition of ozone at CHâC(OH) of catechol proceeds through oxepin derivatives along with the paths leading to Criegee Intermediates and peroxy acids. The 7-membered heterocyclic oxepin derivatives have lower energies than Criegee Intermediates but similar relative energies with peroxy acids.
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This study aims to compare dose escalation between two groups of reirradiated cancer patients, one with the previous contour and radiotherapy plan available on the treatment planning system and the other without. First group is identified as DICOM-group, while the other one is called non-DICOM group. The current study included 89 patients, 57 in the DICOM, and 32 in the non-DICOM group, who received reirradiation for recurrent or second primary tumours between 2019 and 2021. For the DICOM group, doses to 0.2cc volume for spine, brainstem, and optic apparatus from first radiation were converted into structures and transferred to reirradiation CT using deformable registration. First, one radiotherapy plan was created using the doctor prescribed dose (baseline prescription RxD_B); further an escalated dose (RxD_E) plan, taking into account all the dose volume parameters from previous radiation, was created only for DICOM group. In non-DICOM group patients were planned only for RxD_B. The maximum accepted dose escalation was 21 Gy. Radiotherapy prescription dose during earlier (first) treatment in DICOM and non-DICOM groups were 61 ± 5.6 Gy and 30-66 Gy, respectively. DICOM and non-DICOM groups had nearly identical baseline doses: 52.5 ± 10.7 Gy and 50.6 ± 6.9 Gy (difference 1.9 ± 12.7 Gy). Dose escalation was possible for 51 out of 57 patients in the DICOM-group. Average escalated dose in DICOM-group was 59.2 ± 6.2 Gy, with an incremental dose of 6.7 ± 12.4 Gy from the baseline prescription. No dose escalation was opted for in the non-DICOM group due to the unavailability of dose volume information from previous radiation. Reirradiation for head and neck cases allowed for a moderate to high dose escalation, facilitated by the presence of pertinent DICOM information from the initial radiotherapy.
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Neoplasias , Planificación de la Radioterapia Asistida por Computador , Humanos , Dosificación Radioterapéutica , Neoplasias/radioterapiaRESUMEN
Grass carp intestinal waste-mediated biosynthesized nanosilver (AgNPs) was valorized using guaran and zeolite matrices, resulting in AgNPs-guaran, AgNPs-zeolite, and AgNPs-guaran -zeolite composites. The valorized products were examined using Environmental Scanning Electron Microscopy, Energy Dispersive X-ray analysis and X-ray Diffraction analysis to confirm uniform dispersion and entrapment of AgNPs within the matrixes. These valorized products were evaluated for their efficacy in detoxifying the ubiquitous and toxic hexavalent chromium (Cr6+) in aquatic environments, with Anabas testudineus exposed to 2 mg l-1 of Cr6+ for 60 days. Remarkable reduction of Cr6+ concentration to 0.86 ± 0.007 mg l-1 was achieved with AgNPs-guaran-zeolite composite, indicating successful reclamation of contaminated water and food safety assurance. Consistency in results was further corroborated by minimal stress-related alterations in fish physiological parameters and integrated biomarker response within the experimental group treated with the AgNPs-guaran-zeolite composite. Despite observed chromium accumulation in fish tissues, evidence of physiological stability was apparent, potentially attributable to trivalent chromium accumulation, serving as an essential nutrient for the fish. Additionally, the challenge study involving Anabas testudineus exposed to Aeromonas hydrophila exhibited the lowest cumulative mortality (11.11%) and highest survival rate (87.5%) within the same experimental group. The current study presents a novel approach encompassing the valorization of AgNPs for Cr6+ detoxification under neutral to alkaline pH conditions, offering a comprehensive framework for environmental remediation.
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Biomarcadores , Cromo , Nanopartículas del Metal , Plata , Contaminantes Químicos del Agua , Zeolitas , Animales , Cromo/química , Zeolitas/química , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/toxicidad , Plata/química , Plata/toxicidad , Nanopartículas del Metal/química , Nanopartículas del Metal/toxicidad , Hidrogeles/química , Bioacumulación , Inactivación Metabólica , Galactanos , Mananos , Gomas de PlantasRESUMEN
Faba bean (Vicia faba L.) is a winter season grain legume and a rich source of the anti-parkinson drug, L-3,4-dihydroxyphenylalanine (L-DOPA). The biosynthesis of L-DOPA in plants is not uniform and remains largely unexplored. While the hydroxylase activities of Tyrosine Hydroxylase (TH), the Cytochrome P450 (CYP450) class of enzymes, and Polyphenol Oxidases (PPOs) on tyrosine substrate have been reported in plants, only the roles of PPOs in L-DOPA biosynthesis have been recently established in velvet bean (Mucuna pruriens). To understand the differential accumulation of L-DOPA in different tissues of faba bean, profiling of L-Tyrosine, L-DOPA, Tyramine, and Dopamine in different tissues was performed. Differential accumulation of L-DOPA depended on tissue type and maturity. Furthermore, dopamine biosynthesis through L-DOPA from L-Tyr was confirmed in faba bean. The expression analysis of PPOs in leaf and flower tissues revealed the selective induction of only four (HePPO-2, HePPO-7, HePPO-8b, and HePPO-10) out of ten genes encoding different PPOs mined from the faba bean genome. Higher accumulation of L-DOPA in young leaves and flower buds than in mature leaves and flowers was accompanied by significantly higher expression of HePPO-10 and HePPO-7, respectively. The role of various transcription factors contributing to such metabolite dynamics was also predicted. Further exploration of this mechanism using a multi-omics approach can provide meaningful insight and pave the way for enhancing L-DOPA content in crops. Supplementary Information: The online version contains supplementary material available at 10.1007/s12298-024-01449-2.
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Solid-state self-powered UV detection is strongly required in various application fields to enable long-term operation. However, this requirement is incompatible with conventionally used metal-semiconductor-metal (MSM) UV photodetectors (PDs) due to the symmetric design of Schottky contacts. In this work, a self-powered MSM solar-blind UV-PD was realized using a lateral pn junction architecture. A large built-in electric field was obtained in the MSM-type UV-PD without impurity doping, leading to efficiency carrier separation and enhanced photoresponsivity at zero external bias. The solar-blind UV-PD exhibits a cutoff wavelength of 280â nm, a photo/dark current ratio of over 105, and a responsivity of 425.13â mA/W at -10â V. The mechanism of self-powered UV photodetection was further investigated by TCAD simulation of the internal electric field and carrier distributions.
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The current study investigates the potential utilization of poultry intestines for the synthesis of stable silver nanoparticles (AgNPs) and their impact on fish physiology. The AgNPs were synthesized and characterized using various analytical techniques. The toxicity of AgNPs on Anabas testudineus was evaluated, determining a 96-h LC50 value of 25.46 mg l-1. Subsequently, fish were exposed to concentrations corresponding to 1/10th, 1/25th, 1/50th, and 1/100th of the estimated LC50 for a duration of 60 days in a sub-acute study. A comprehensive range of biomarkers, including haematological, serum, oxidative stress, and metabolizing markers, were analyzed to assess the physiological responses of the fish. Additionally, histopathological examinations were conducted, and the accumulation of silver in biomarker organs was measured. The results indicate that silver tends to bioaccumulate in all biomarker organs in a dose- and time-dependent manner, except for the muscle tissue, where accumulation initially increased and subsequently decreased, demonstrating the fish's inherent ability for natural attenuation. Analysis of physiological data and integrated biomarker responses reveal that concentrations of 1/10th, 1/25th, and 1/50th of the LC50 can induce stress in the fish, while exposure to 1/100th of the LC50 shows minimal to no stress response. Overall, this study provides valuable insights into the toxicity and physiological responses of fish exposed to poultry waste biosynthesized AgNPs, offering potential applications in aquaculture while harnessing their unique features.
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Nanopartículas del Metal , Animales , Nanopartículas del Metal/toxicidad , Plata/toxicidad , Aves de Corral , Peces , Acuicultura , BiomarcadoresRESUMEN
On-the-fly dynamics simulations are performed for the reaction of catechol + O3. The post transition state (TS) dynamics is studied at temperatures of 400 and 500 K. The PM7 semiempirical method is employed for calculating the potential energy gradient needed for integrating Hamilton's equations of motion. This semiempirical method provides excellent agreement in terms of energy and geometry of the TSs as well as minimum energy states of the system with respect to B3LYP/6-311+G (2df, 2p) calculated results. In the dynamics, first, a peroxyacid is formed, which further dissociates to different fragments. Four major channels forming CO, CO2, H2O, and small carboxylic acid (SCA) fragments are seen in this reaction. Rates of each of the channels and the overall unimolecular reaction are calculated at both temperatures. Branching ratios of all these product channels are calculated and compared with experiment. The minimum energy profile of CO2, CO, and H2O channels are calculated. A qualitative estimate of activation energies for all the channels are obtained and compared with the explicit TS energies of three product channels, which ultimately correlate with the reaction probabilities.
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Dióxido de Carbono , Ozono , Ácidos Carboxílicos , CatecolesRESUMEN
One of the major constraints against using polymeric scaffolds as tissue-regenerative matrices is a lack of adequate implant vascularization. Self-assembling peptide hydrogels can sequester small molecules and biological macromolecules, and they can support infiltrating cells in vivo. Here we demonstrate the ability of self-assembling peptide hydrogels to facilitate angiogenic sprouting into polymeric scaffolds after subcutaneous implantation. We constructed two-component scaffolds that incorporated microporous polymeric scaffolds and viscoelastic nanoporous peptide hydrogels. Nanofibrous hydrogels modified the biocompatibility and vascular integration of polymeric scaffolds with microscopic pores (pore diameters: 100-250 µm). In spite of similar amphiphilic sequences, charges, secondary structures, and supramolecular nanostructures, two soft hydrogels studied herein had different abilities to aid implant vascularization, but had similar levels of cellular infiltration. The functional difference of the peptide hydrogels was predicted by the difference in the bioactive moieties inserted into the primary sequences of the peptide monomers. Our study highlights the utility of soft supramolecular hydrogels to facilitate host-implant integration and control implant vascularization in biodegradable polyester scaffolds in vivo. Our study provides useful tools in designing multi-component regenerative scaffolds that recapitulate vascularized architectures of native tissues.
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Traumatic brain injury (TBI) is associated with poor intrinsic healing responses and long-term cognitive decline. A major pathological outcome of TBI is acute glutamate-mediated excitotoxicity (GME) experienced by neurons. Short peptides based on the neuroprotective extracellular glycoprotein ependymin have shown the ability to slow down the effect of GME - however, such short peptides tend to diffuse away from target sites after in vivo delivery. We have designed a self-assembling peptide containing an ependymin mimic that can form nanofibrous matrices. The peptide was evaluated in situ to assess neuroprotective utility after an acute fluidpercussion injury. This biomimetic matrix can conform to the intracranial damaged site after delivery, due its shear-responsive rheological properties. We demonstrated the potential efficacy of the peptide for supporting neuronal survival in vitro and in vivo. Our study demonstrates the potential of these implantable acellular hydrogels for managing the acute (up to 7 days) pathophysiological sequelae after traumatic brain injury. Further work is needed to evaluate less invasive administrative routes and long-term functional and behavioral improvements after injury.
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OBJECTIVE: Accurate calculation of set-up margin is a prerequisite to arrive at the most optimal clinical to planning target volume margin. The aim of this study was to evaluate the compatibility of different on-board and in-room stereoscopic imaging modalities by calculating the set-up margins (SM) in stereotactic body radiotherapy technique accounting and unaccounting for rotational positional errors (PE). Further, we calculated separate SMs one based on residual positional errors and another based on residual + intrafraction positional errors from the imaging data obtained in a dual imaging environment. MATERIALS AND METHODS: A total of 22 lung cancer patients were included in this study. For primary image guidance, four-dimensional cone beam computed tomography (4-D CBCT) was used and stereoscopic ExacTrac was used as the auxiliary imaging. Following table position correction (TPC) based on the initial 4-D CBCT, another 4-D CBCT (post-TPC) and a pair of stereoscopic ExacTrac images were obtained. Further, during the treatment delivery, a series of ExacTrac images were acquired to identify the intrafraction PE. If a, b and c were the observed translational shifts in lateral (x-axis), longitudinal (y-axis) and vertical direction (z-axis) and α, ß and γ were the rotational shifts in radians about the same axes, respectively, then the resultant translational vectors (A, B and C) were calculated on the basis of translational and rotational values. Set-up margins were calculated using residual errors post-TPC only and also using intrafraction positional errors in addition to the residual errors. RESULTS: Residual and residual + intrafraction SM were calculated from a dataset of 82 CBCTs and 189 ExacTrac imaging sessions. CBCT-based mean ± SD shifts in translational and rotational directions were 0.3 ± 1.8 mm, 0.1 ± 1.8 mm, - 0.4 ± 1.6 mm, 0.1 ± 0.4°, 0.0 ± 1.0° and 0.3 ± 0.7°, respectively, and for ExacTrac - 0.1 ± 1.8 mm, 0.2 ± 2.4 mm, - 0.6 ± 1.8 mm, 0.1 ± 1.2°, - 0.2 ± 1.3° and - 0.1 ± 0.6°, respectively. Residual SM without considering the rotational correction in x, y and z directions were 5.0 mm, 4.5 mm and 4.4 mm; rotation-corrected SM were 4.4 mm, 4.0 mm and 5.5 mm, respectively. Residual plus intrafraction SM were 5.5 mm, 6.6 mm and 6.2 mm without considering the rotational corrections, whereas they were 5.0 mm, 6.3 mm and 6.2 mm with rotational errors accounted for. CONCLUSION: Accurate calculation of set-up margin is required to find the clinical to planning target volume margin. Primary and auxiliary imaging margins fall in the range of 4.0 to 5.5 mm and 5.0 to 7.0 mm, respectively, indicating a higher SM for X-ray-based planar imaging techniques over three-dimensional cone beam images. This study established the degree of mutual compatibility between two different kinds of widely used set-up imaging modalities, on-board CBCT and in-room stereoscopic imaging ExacTrac. It also describes the technique to calculate the residual and residual plus intrafraction SM and its variation in a dual imaging environment accounting for rotational PE in stereotactic body radiotherapy of lung.
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Tomografía Computarizada de Haz Cónico/métodos , Tomografía Computarizada Cuatridimensional/métodos , Neoplasias Pulmonares/radioterapia , Pulmón/diagnóstico por imagen , Planificación de la Radioterapia Asistida por Computador/métodos , Radioterapia Guiada por Imagen/métodos , Adulto , Anciano , Femenino , Humanos , Neoplasias Pulmonares/diagnóstico , Masculino , Persona de Mediana EdadRESUMEN
BACKGROUND: Suprascapular nerve (SSN) block is a useful tool for pain control of different chronic shoulder pain syndromes. If the short-term effect of nerve block using local anesthetics is not sufficient, pulsed radiofrequency (PRF) neuromodulation of the SSN may provide long-term pain relief. AIM OF INVESTIGATION: The aim of this study was to determine the effectiveness of ultrasonography-guided PRF of the SSN for management of chronic shoulder pain. SUBJECTS AND METHOD: Thirty patients with chronic shoulder pain underwent diagnostic ultrasonography-guided SSN block. After confirmation of positive results (>50% pain relief) via diagnostic testing, PRF of the SSN was performed in 27 patients, followed by application of dexamethasone; however, 2 patients had negative results with diagnostic block and 1 patient dropped out after positive results with diagnostic block. Pain was recorded using the VAS, and active range of motion of the affected shoulder was measured by goniometry (flexion, extension, adduction, abduction, external rotation, internal rotation). Assessments were done on day 0 and after 4, 8, 12, and 24 weeks. STATISTICAL TEST: One-way analysis of variance testing. RESULTS: The VAS score decreased significantly (P < 0.05) immediately after injection, and pain reduction was sustained for up to 24 weeks. Active range of motion in all directions also increased significantly (P < 0.5) after the procedure. CONCLUSION: PRF of the SSN under ultrasonography guidance is a safe and effective treatment modality for management of chronic shoulder pain. The effect of a combination of PRF and a short-acting corticosteroid lasts up to 24 weeks, thereby assisting patients in undergoing relatively painless physiotherapy.
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Tratamiento de Radiofrecuencia Pulsada/métodos , Dolor de Hombro/terapia , Ultrasonografía Intervencional/métodos , Adulto , Anestésicos Locales/administración & dosificación , Dolor Crónico/terapia , Femenino , Humanos , Inyecciones Intraarticulares , Lidocaína/administración & dosificación , Masculino , Persona de Mediana Edad , Bloqueo Nervioso/métodos , Resultado del TratamientoRESUMEN
A detailed theoretical investigation of gas-phase 1,3-cycloaddition of ozone with catechol is presented to explore the discrepancies in previous theoretical and experimental rate constants. DFT based PBE, TPSS, B3LYP, B3PW91, M06-2X, wB97XD, MN15 and high-level CCSD(T) methods are used for the calculation. Canonical transition state theory has been used to calculate the rate coefficients of individual steps. The calculated rate coefficients are compared with the experimental and previously calculated rate constant. The possible pathways for primary ozonide (POZ) formation and subsequent reactions to yield the Criegee Intermediates (CI) and peroxy acids (POA) are investigated. The endo-POZ may undergo conversion to exo-POZ or form the Creigee Intermediates. This work shows a novel pathway by which the exo-POZ can form more stable and chemically different species, peroxy acids, by abstracting an H atom from the OH group.
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High-resolution X-ray crystallography and two-dimensional NMR studies demonstrate that water-mediated conventional hydrogen-bonding interactions (N-H···N, O-H···N, etc.) bridging two or more amino acid residues contribute to the stability of proteins and protein-ligand complexes. In this work, we have investigated single water-mediated selenium hydrogen-bonding interactions (unconventional hydrogen-bonding) between amino acid residues in proteins through extensive protein data bank (PDB) analysis coupled with gas-phase spectroscopy and quantum chemical calculation of a model complex consisting of indole, dimethyl selenide, and water. Here, indole and dimethyl selenide represent the amino acid residues tryptophan and selenomethionine, respectively. The current investigation demonstrates that the most stable structure of the model complex observed in the IR spectroscopy mimics single water-mediated selenium hydrogen-bonded structural motifs present in the crystal structures of proteins. The present work establishes that water-mediated Se hydrogen-bonding interactions are ubiquitous in proteins and the number of these interactions observed in the PDB is more than that of direct Se hydrogen-bonds present there.
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Proteínas/química , Selenio/química , Agua/química , Biología Computacional , Cristalografía por Rayos X , Bases de Datos de Proteínas , Enlace de Hidrógeno , Indoles/química , Ligandos , Modelos Moleculares , Compuestos de Organoselenio/química , Teoría Cuántica , Selenometionina/química , Espectrofotometría Infrarroja , Triptófano/químicaRESUMEN
Specific folded structures of peptides and proteins depend on the sequence of various amino acid residues as well as different types of noncovalent interactions induced by the backbone as well as side-chains of those residues. In general, secondary structures of peptides and proteins are stabilized by C6 (δ-turn), C7 (γ-turn), C10 (ß-turn), C13 (α-turn), and C15 (π-turn) hydrogen-bonded rings formed through inter-residue interactions. However, it has been reported recently that an intraresidue C5 hydrogen-bond, which is relatively weak in strength, can contribute significantly to the stability of peptides and proteins. The C5 hydrogen-bond is mostly present in the ß-sheet structures of peptides and proteins along with other inter-residue noncovalent interactions. In this work, we have studied structures and conformational preferences of a dipeptide Z-Gly-Pro-OH (Z = benzyloxycarbonyl) using mass-selected vibrationally resolved electronic spectroscopy and IR-UV double resonance spectroscopy coupled with quantum chemistry calculations. Two conformers of the peptide are observed in the experiment. One of the conformers has an extended ß-strand type structure stabilized by C5 hydrogen-bonding, while the other one is folded through O-H ⯠π interaction. The noncovalent interactions present in the two observed structures of the peptide are validated by natural bond orbital and noncovalent interaction calculations.
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Dipéptidos/química , Péptidos/química , Enlace de Hidrógeno , Pliegue de Proteína , Estructura Secundaria de ProteínaRESUMEN
We describe progress and obstacles in the development of novel peptide-hydrogel therapeutics for unmet medical needs in ischemia treatment, focusing on the development and translation of therapies specifically in peripheral artery disease (PAD). Ischemia is a potentially life-threatening complication in PAD, which affects a significant percentage of the elderly population. While studies on inducing angiogenesis to treat PAD were started two decades ago, early results from animal models as well as clinical trials have not yet been translated into clinical practice. We examine some of the challenges encountered during such translation. We further note the need for sustained angiogenic effect involving whole growth factor, gene therapy and synthetic growth factor strategies. Finally, we discuss the need for tissue depots for de novo formation of microvasculature. These scaffolds can act as templates for neovasculature development to improve circulation and healing at the preferred anatomical location.
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Proteínas Angiogénicas/uso terapéutico , Isquemia/tratamiento farmacológico , Investigación Biomédica Traslacional , Animales , Modelos Animales de Enfermedad , Descubrimiento de Drogas , Humanos , Neovascularización Fisiológica/efectos de los fármacosRESUMEN
The focus of this study is to measure ecological stress of Churni River based on the estimates of dissolved oxygen (DO), pH, biological oxygen demand (BOD), chemical oxygen demand (COD), nutrients imbalances of dissolved inorganic nitrogen or DIN (NO3- N and NO2- N) and dissolved inorganic phosphate or DIP (PO43-). The present water quality measured in terms of overall index of pollution (OIP), eutrophication index (EI), organic pollution (OPI) and water pollution indexes for ecological status (WPI) portrays that the river is polluted having a high concentration of BOD, COD, nutrients (DIP and DIN) and a very low concentration of DO. Fish community structure taken as most sensitive indicator of ecological stress of water pollution depicts that out of 44 species, 28 fish species (63.63%) comprising 20.0% planktivore (PL), 9.09% benthic feeder (BE), 18.18% omnivorous (OM) and 15.90% carnivorous (CA) at Majhdia and 21 fish species (47.72%) comprising 18.18% PL, 4.59% BE, 13.63% OM and 11.36% CA at Ranaghat have been disappeared. The present investigation has found that anthropogenic interventions like disposal of industrial effluents and agricultural run-off from on-bed and off bed land use are the main drivers of the pollution. Furthermore, natural forcing in the form of neotectonic movements and monsoon regimes has intensified the problem.
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Monitoreo del Ambiente , Contaminantes Químicos del Agua/análisis , Contaminación del Agua/estadística & datos numéricos , Animales , Análisis de la Demanda Biológica de Oxígeno , Ecología , Eutrofización , Peces , India , Ríos/química , Contaminantes Químicos del Agua/química , Contaminación del Agua/análisis , Calidad del AguaRESUMEN
OBJECTIVES: Radiotherapy for breast cancer has been associated with various side effects including cardiac sequelae. Our study aimed to define the spatial arc of spread of coronary vessels in a radian angle. MATERIALS AND METHODS: We analysed the records of 51 CT coronary angiographies done in our hospital from January 2016 to July 2016. Left anterior descending (LAD) and right coronary (RC) were contoured for each patient. In each axial section, the radial spread of each artery was noted. A 5â¯mm brush tool was used to join the start and stop angles for making the summated "coronary strips". RESULTS: Start and end angle of LAD with 95% confidence interval (CI) (in clockwise direction) were 23.9⯱ 4° and 79.0⯱ 6.6°, respectively. Mean LAD arc length⯱ SD (standard deviation) noted was 55.1°â¯± 7.7° (95% CI). For RC the smallest start angle and the largest end angle in all patients was 297.6° and 322.6°, respectively. RC start angle, end angle and arc length for 95% confidence interval were 322.2⯱ 6.1°, 292.4⯱ 11.6° and 29.8⯱ 13.1°, respectively. CONCLUSIONS: Our study provides a measure of the radial spread of the coronary arteries, especially from the perspective of breast radiotherapy. We have proposed a new organ at risk (OAR) of coronary strip. This should provide an easy and cost-effective way to delineate the coronary vasculature in breast cancer patients undergoing radiotherapy.
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Neoplasias de la Mama/radioterapia , Enfermedad de la Arteria Coronaria/etiología , Vasos Coronarios/efectos de la radiación , Órganos en Riesgo , Traumatismos por Radiación/etiología , Neoplasias Torácicas/radioterapia , Adulto , Anciano , Angiografía por Tomografía Computarizada , Angiografía Coronaria , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/prevención & control , Vasos Coronarios/diagnóstico por imagen , Femenino , Humanos , Interpretación de Imagen Asistida por Computador , Masculino , Persona de Mediana Edad , Traumatismos por Radiación/diagnóstico por imagen , Traumatismos por Radiación/prevención & control , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador , Factores de RiesgoRESUMEN
Implantation of acellular biomimetic scaffolds with proangiogenic motifs may have exciting clinical utility for the treatment of ischemic pathologies such as myocardial infarction. Although direct delivery of angiogenic proteins is a possible treatment option, smaller synthetic peptide-based nanostructured alternatives are being investigated due to favorable factors, such as sustained efficacy and high-density epitope presentation of functional moieties. These peptides may be implanted in vivo at the site of ischemia, bypassing the first-pass metabolism and enabling long-term retention and sustained efficacy. Mimics of angiogenic proteins show tremendous potential for clinical use. We discuss possible approaches to integrate the functionality of such angiogenic peptide mimics into self-assembled peptide scaffolds for application in functional tissue regeneration.