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1.
Plant Physiol ; 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38701036

RESUMEN

The strong ability of plants to regenerate wounds is exemplified by grafting when two plants are cut and joined together to grow as one. During graft healing, tissues attach, cells proliferate, and the vasculatures connect to form a graft union. The plant hormone auxin plays a central role, and auxin-related mutants perturb grafting success. Here, we investigated the role of individual cell types and their response to auxin during Arabidopsis (Arabidopsis thaliana) graft formation. By employing a cell-specific inducible misexpression system, we blocked auxin response in individual cell types using the bodenlos mutation. We found that auxin signaling in procambial tissues was critical for successful tissue attachment and vascular differentiation. In addition, we found that auxin signaling was required for cell divisions of the procambial cells during graft formation. Loss of function mutants in cambial pathways also perturbed attachment and phloem reconnection. We propose that cambial and procambial tissues drive tissue attachment and vascular differentiation during successful grafting. Our study thus refines our knowledge of graft development and furthers our understanding of the regenerative role of the cambium.

2.
Development ; 147(6)2020 03 30.
Artículo en Inglés | MEDLINE | ID: mdl-32108025

RESUMEN

Aerial organs of plants, being highly prone to local injuries, require tissue restoration to ensure their survival. However, knowledge of the underlying mechanism is sparse. In this study, we mimicked natural injuries in growing leaves and stems to study the reunion between mechanically disconnected tissues. We show that PLETHORA (PLT) and AINTEGUMENTA (ANT) genes, which encode stem cell-promoting factors, are activated and contribute to vascular regeneration in response to these injuries. PLT proteins bind to and activate the CUC2 promoter. PLT proteins and CUC2 regulate the transcription of the local auxin biosynthesis gene YUC4 in a coherent feed-forward loop, and this process is necessary to drive vascular regeneration. In the absence of this PLT-mediated regeneration response, leaf ground tissue cells can neither acquire the early vascular identity marker ATHB8, nor properly polarise auxin transporters to specify new venation paths. The PLT-CUC2 module is required for vascular regeneration, but is dispensable for midvein formation in leaves. We reveal the mechanisms of vascular regeneration in plants and distinguish between the wound-repair ability of the tissue and its formation during normal development.


Asunto(s)
Arabidopsis , Redes Reguladoras de Genes/fisiología , Hojas de la Planta/fisiología , Tallos de la Planta/fisiología , Haz Vascular de Plantas/fisiología , Regeneración/genética , Arabidopsis/genética , Arabidopsis/crecimiento & desarrollo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/fisiología , Regulación de la Expresión Génica de las Plantas , Ácidos Indolacéticos/metabolismo , Péptidos y Proteínas de Señalización Intercelular/genética , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Oxigenasas de Función Mixta/genética , Oxigenasas de Función Mixta/metabolismo , Desarrollo de la Planta/fisiología , Hojas de la Planta/genética , Hojas de la Planta/crecimiento & desarrollo , Tallos de la Planta/genética , Tallos de la Planta/crecimiento & desarrollo , Haz Vascular de Plantas/genética , Plantas Modificadas Genéticamente , Regiones Promotoras Genéticas , Transducción de Señal/genética , Factores de Transcripción/fisiología , Cicatrización de Heridas/genética
3.
Inorg Chem ; 62(8): 3457-3463, 2023 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-36763341

RESUMEN

Three new metal organic frameworks (ZnTIA-1mc, CuTIA-1mc, and CoTIA-1mc) were synthesized by the mechanochemical grinding (mc) method in the unadulterated form. They compared with their solvothermally synthesized (st) counterparts, where the mixtures of isomeric forms have been isolated. Kinetics study with the function of grinding time during the mechanosynthesis process revealed the formation of new metastable phases. Less crystallinity and short of mechanical defects in the structure of synthesized mc metal organic frameworks showed enhanced electrocatalytic activity toward oxygen evolution reaction (OER). Among all, CoTIA-1mc showed high OER activity with 289 mV overpotential, 10 mA cm-2 current density, and 55.4 mV dec-1 Tafel slope in 1 M KOH which is close to the commercially used RuO2.

4.
Bioprocess Biosyst Eng ; 44(7): 1461-1476, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33818638

RESUMEN

Biomediated ecofriendly method for the synthesis of nickel oxide nanoparticles using plants extracts (Toona ciliata, Ficus carica and Pinus roxburghii) has been reported. The nanoparticles so obtained were characterized by various techniques such as ultraviolet-visible, powder X-ray diffraction, Fourier transform infrared spectroscopy, attenuated total reflectance spectroscopy, scanning electron microscopy, transmission electron microscopy, energy dispersive X-ray spectroscopy, thermogravimetric analysis and fluorescence spectroscopy. Formation of nickel oxide nanoparticles was confirmed by Fourier transform infrared spectroscopy and X-ray diffraction where the former technique ascertains the formation of bond between nickel and oxygen. The nickel oxide nanoparticles were found to be crystalline cubic face centered and show intense photoluminescence emission at 416, 414 and 413 nm, respectively. The antibacterial activity was studied against gram positive and gram negative bacterial species by agar well diffusion method. The nickel oxide nanoparticles show better activity against some bacterial strains with reference to the standard drugs Ciprofloxacin and Gentamicin. The anthelmintic activity against Pheretima posthuma of nanomaterials obtained from Pinus roxburghii was found to be greater than that derived from Toona ciliata and Ficus carica using the standard drug Albendazole. This method takes the advantage of the sustainable and economic approach for the synthesis of metal oxide nanoparticles.


Asunto(s)
Biotecnología/métodos , Ficus/metabolismo , Níquel/química , Pinus/metabolismo , Toona/metabolismo , Albendazol/química , Ciprofloxacina/química , Gentamicinas/química , Tecnología Química Verde/métodos , Nanopartículas del Metal/química , Pruebas de Sensibilidad Microbiana , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , Nanopartículas/química , Oxígeno/química , Tamaño de la Partícula , Extractos Vegetales/química , Espectrometría de Fluorescencia , Espectroscopía Infrarroja por Transformada de Fourier , Temperatura , Termogravimetría , Difracción de Rayos X
5.
Microb Pathog ; 129: 233-241, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30794877

RESUMEN

Zinc oxide nanoparticles derived from Malus pumila (apple) and Juglen regia (walnut) plant is an attractive area of research because of their widespread use. The use of plant material to synthesize zinc oxide nanoparticles has been considered as one of the best environmentally friendly approach. This method appears to be low-cost as compare to other conventional method of synthesis. The biosynthesized nanoparticles were characterized by Ultraviolet-visible spectroscopy (UV-visible), Fourier transform infrared spectroscopy (FT-IR), Attenuated total reflectance spectroscopy (ATR), X-ray diffraction (XRD), Scanning electron microscopy (SEM), Energy dispersive X-ray spectroscopy (EDX), Transmission electron Microscopy (TEM) and Dynamic light scattering (DLS). The antioxidant potential has been evaluated by 2, 2-diphenyl-1-picrylhydrazyl free radical (DPPH) assay using L-ascorbic acid as a standard. The antibacterial activity was measured by agar well diffusion method to measure the efficacy of plant species extract and extract mediated zinc oxide nanoparticles against 5 g positive bacteria namely Staphylococcus aureus (S. aureus), Streptococcus mutans (S. mutans), Streptococcus pyrogenes (S. pyrogenes), Corynebacterium diphtheriae (C. diphtheriae) and Corynebacterium xerosis (C. xerosis) and 3 g negative bacteria such as Escherichia coli (E. coli), Klebsiella pneumoniae (K. pneumoniae) and Pseudomonas aeruginosa (P. aeruginosa) bacteria with standard antibiotic for gram positive (Ciprofloxacin) and gram negative bacteria (Gentamicin).


Asunto(s)
Antibacterianos/farmacología , Antioxidantes/farmacología , Bacterias/efectos de los fármacos , Juglans/metabolismo , Malus/metabolismo , Nanopartículas del Metal/química , Óxido de Zinc/farmacología , Antibacterianos/química , Antibacterianos/metabolismo , Antioxidantes/química , Antioxidantes/metabolismo , Técnicas de Química Analítica , Corynebacterium diphtheriae , Nanopartículas del Metal/ultraestructura , Pruebas de Sensibilidad Microbiana , Microscopía Electrónica , Óxido de Zinc/química , Óxido de Zinc/metabolismo
6.
Chem Biodivers ; 16(8): e1900145, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31207044

RESUMEN

Copper oxide nanomaterials were synthesized by a facile sustainable biological method using two plant species (Zanthoxylum armatum DC. and Berberis lycium Royle). The formation of materials was confirmed by FT-IR, ATR, UV-visible, XRD, TEM, SEM, EDX, TGA and PL. The antibacterial activity was evaluated by agar well diffusion method to ascertain the efficacy of plant species extract and extract derived copper oxide nanomaterials against six Gram-positive bacteria namely Staphylococcus aureus, Streptococcus mutans, Streptococcus pyogenes, Corynebacterium diphtheriae, Corynebacterium xerosis, Bacillus cereus and four Gram-negative bacteria such as Klebsiella pneumonia, Escherichia coli, Pseudomonas aeruginosa and Proteus vulgaris against the standard drug, Ciprofloxacin for Gram-positive and Gentamicin for Gram-negative bacteria, respectively. In both cases, copper oxide nanomaterials were found to be sensitive in all the bacterial species. Sensitivity of copper oxide nanomaterials shows an be higher as compared to plant species extract against different bacteria. Scavenging activity of plant extracts along with nanomaterials have been accessed using previously reported protocols employing ascorbic acid as standard. Scavenging activity of copper oxide nanomaterials shows an increase with increase in concentration. The biological activity (bactericidal and scavenging efficiency) of plant derived copper oxide nanomaterials revealed that these materials can be used as potent antimicrobial agent and DPPH scavengers in industrial as well as pharmacological fields.


Asunto(s)
Antibacterianos/química , Berberis/química , Cobre/química , Depuradores de Radicales Libres/química , Nanoestructuras/química , Zanthoxylum/química , Antibacterianos/farmacología , Berberis/metabolismo , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Tecnología Química Verde , Pruebas de Sensibilidad Microbiana , Nanoestructuras/toxicidad , Hojas de la Planta/química , Espectroscopía Infrarroja por Transformada de Fourier , Zanthoxylum/metabolismo
7.
J Pak Med Assoc ; 69(2): 183-189, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30804581

RESUMEN

OBJECTIVE: To identify the underlying genetic anomalies in two consanguineous Pakistani families with autosomal recessive achromatopsia. METHODS: The exploratory study was conducted under the patronage of International Islamic University, Islamabad, Pakistan, and Sungshin Women University, Seoul, South Korea, after two families coded PKCN-02 and PKCN-07 belonging to different ethnic groups were recruited from different areas of Khyber Pakhtunkhawa province of Pakistan in July 2016. The families were originally diagnosed with nystagmus upon medical examination. Exome sequencing was performed to identify the possible causative gene which was found to be cyclic nucleotide-gated channel alpha-3. Sanger sequencing was performed to confirm the mutations. After genetic analysis, clinical analysis was re-evaluated for colour vision using Ishihara 26 plates. Pathogenic potential of these mutations was evaluated using algorithmic mutation prediction tools. In-silico analysis was performed to predict effect of these mutations on protein structure of the gene in question. RESULTS: Exome sequencing revealed a reported missense mutation c .1306C>T (p.R436W) in family PKCN-02 and a novel missense mutation c.1540G>A (p.D514N) in family PKCN-07. After mutational analysis, clinical re-evaluation revealed that both families were segregating autosomal recessive achromatopsia. Further, the topological model of the cyclic nucleotide-gated channel alpha-3 polypeptide describes these missense mutations primarily affecting the C-linker and cyclic guanosine monophosphate-binding sites, respectively. Protein structure modelling of cyclic nucleotide-gated channel alpha-3 protein revealed abnormal structure produced by p.R436W and p.D514N.. CONCLUSIONS: Exome sequencing approach was used to first identify the genetic alteration in families with nystagmus. Two mutations in cyclic nucleotide-gated channel alpha-3gene were uncovered, including one novel mutation. Clinical re-evaluation uncovered that both families had achromatopsia.


Asunto(s)
Defectos de la Visión Cromática , Canales Catiónicos Regulados por Nucleótidos Cíclicos/genética , Nistagmo Patológico , Adulto , Transporte Biológico Activo/genética , Pruebas de Percepción de Colores/métodos , Defectos de la Visión Cromática/diagnóstico , Defectos de la Visión Cromática/etnología , Defectos de la Visión Cromática/genética , Femenino , Estudios de Asociación Genética , Humanos , Masculino , Mutación Missense , Nistagmo Patológico/diagnóstico , Nistagmo Patológico/etiología , Pakistán , Linaje , Polimorfismo Genético , Agudeza Visual , Secuenciación del Exoma
8.
Plant Cell Physiol ; 59(4): 702-707, 2018 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-29361166

RESUMEN

The initial view that regeneration can be a continuum in terms of regulatory mechanisms is gradually changing, and recent evidence points towards the presence of discrete regulatory steps and intermediate phases. Furthermore, regeneration presents an excellent example of a process generating order and pattern, i.e. a self-organization process. It is likely that the process traverses a set of intermediate phases before reaching an endpoint. Although some progress has been made in deciphering the identity of these intermediate phases, a lot more work is needed to derive a comprehensive and complete picture. Here, we discuss the intermediate developmental phases in plant regeneration and compare them with the possible intermediate developmental phases in animal regeneration.


Asunto(s)
Desarrollo de la Planta , Regeneración , Tipificación del Cuerpo , Linaje de la Célula , Modelos Biológicos , Células Madre/citología , Células Madre/metabolismo
10.
Microb Pathog ; 110: 414-425, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28729223

RESUMEN

Salen ligands comprising of o-phenylenediamine (salop) and p-phenylenediamine (salpp) have been synthesized. The salen ligand, salop undergo Schiff base reaction with Formaldehyde and Barbituric acid to generate novel polymeric Schiff base, SBOPA in one instance while the second salen ligand, salpp on Schiff base reaction with formaldehyde and piperazine gives another novel polymeric Schiff base, SBPBA. These polymeric Schiff base ligands, SBOPA and SBPBA generates polymeric metal complexes in high yields on reaction with transition metal acetates, M(CH3COO)2.xH2O where M = Mn(II), Co(II), Ni(II), Cu(II) and Zn(II). The polymeric Schiff bases, SBOPA and SBPBA and their transition metal complexes were systematically characterized, using various spectroscopic techniques. The structure, composition and geometry of SBOPA and SBPBA and their metal complexes were confirmed by spectral techniques (FT-IR, and 1H NMR), elemental analysis, and electronic spectra magnetic moment. On the basis of FT-IR, 1HNMR, electronic spectra and magnetic moment values Mn(II), Co(II) and Ni(II) ion were found to have octahedral geometry while Cu(II) and Zn(II) were found to be square-planar in nature. Thermogravimetric analysis (TGA) was used to evaluate their thermal behaviour and Cu(II)-SBOPA and Cu(II)-SBPBA were found to be thermally most stable. The polymeric Schiff base ligands, SBOPA and SBPBA and their metal complexes have also been screened for their plausible antimicrobial activity. Tetracyclin and Miconazole were used as standard drug to study the antibacterial and antifungal activity respectively. The Cu(II)-SBOPA and Cu(II)-SBPBA were found to be most potent antimicrobial agents.


Asunto(s)
Antibacterianos/síntesis química , Cobalto/química , Complejos de Coordinación/síntesis química , Cobre/química , Manganeso/química , Níquel/química , Bases de Schiff/síntesis química , Zinc/química , Antibacterianos/química , Antibacterianos/farmacología , Antifúngicos/farmacología , Bacterias/efectos de los fármacos , Barbitúricos/química , Complejos de Coordinación/química , Complejos de Coordinación/farmacología , Análisis Diferencial Térmico , Etilenodiaminas/síntesis química , Etilenodiaminas/química , Formaldehído/química , Ligandos , Espectroscopía de Resonancia Magnética , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Fenilendiaminas/síntesis química , Piperazina , Piperazinas/química , Bases de Schiff/química , Bases de Schiff/farmacología , Espectroscopía Infrarroja por Transformada de Fourier , Termogravimetría
11.
Mol Plant ; 17(1): 75-91, 2024 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-38102831

RESUMEN

People have grafted plants since antiquity for propagation, to increase yields, and to improve stress tolerance. This cutting and joining of tissues activates an incredible regenerative ability as different plants fuse and grow as one. For over a hundred years, people have studied the scientific basis for how plants graft. Today, new techniques and a deepening knowledge of the molecular basis for graft formation have allowed a range of previously ungraftable combinations to emerge. Here, we review recent developments in our understanding of graft formation, including the attachment and vascular formation steps. We analyze why plants graft and how biotic and abiotic factors influence successful grafting. We also discuss the ability and inability of plants to graft, and how grafting has transformed both horticulture and fundamental plant science. As our knowledge about plant grafting improves, new combinations and techniques will emerge to allow an expanded use of grafting for horticultural applications and to address fundamental research questions.


Asunto(s)
Agricultura , Plantas , Agricultura/métodos
12.
Chemosphere ; 351: 141219, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38224750

RESUMEN

Degradation of antibiotics through electrocatalytic oxidation has recently been comprehended as a promising strategy in wastewater treatment. Herein, nitrogen and sulphur doped graphene oxide (N,S-rGO) nanosheets were synthesized and employed as metal-free anodic material for electrochemical degradation of antibiotics, viz. metronidazole (MNZ) and tetracycline (TC). The synthesized anodic material was characterized using various spectral techniques and further the electrochemical behaviour of N,S-rGO was thoroughly examined. Thereafter, the N,S-rGO material was then employed as the anode material towards the electrocatalytic degradation of antibiotics. Parameters such as initial concentration of the antibiotics and current densities were varied and their effect towards the degradation of MNZ and TC were probed. Notably, the N,S-rGO based anode has shown impressive removal efficiency of 99% and 98.5%, after 120 min of reaction time for MNZ and TC, respectively, under optimized conditions. The obtained results including the kinetic parameters, removal efficiency and electrical efficiency ensure that the prepared anodic material has huge prospective towards real-time application for removal of antibiotics from water.


Asunto(s)
Metronidazol , Aguas Residuales , Metronidazol/análisis , Carbono , Estudios Prospectivos , Antibacterianos/química , Tetraciclina/química , Metales , Electrodos
13.
Dalton Trans ; 53(15): 6568-6574, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38529572

RESUMEN

Three new isostructural MOFs (ZnTIA, CoTIA and CdTIA) were synthesized by the solvothermal synthesis of the organic linker 5-triazole isophthalic acid (5-TIA) with the transition metals Zn(II), Co(II) and Cd(II) in the presence of the structure directing agent tetramethyl ammonium chloride (TMA). These three MOFs were characterized thoroughly by ScXRD, PXRD, FT-IR, TGA, BET and SEM. They have excellent thermal and water stabilities. Among all these MOFs mentioned, pristine CoTIA exhibited excellent electrocatalytic activity toward the oxygen evolution reaction (OER). It exhibits a Tafel slope of 68.9 mV dec-1 with an overpotential of 337 mV at 10 mA cm-2 current density. The OER activity of the CoTIA MOF is relatively equivalent to that of the state-of-the-art catalyst (RuO2). Furthermore, the mechanical stability of crystalline ZnTIA, CoTIA and CdTIA MOFs was tested under ball mill pressure. The result showed that all the MOFs exhibit low tolerance to mechanical force because their structure was highly distorted or collapsed under such pressure, which is reflected by their poor electrocatalytic OER activity.

14.
Chemosphere ; 360: 142408, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38789056

RESUMEN

A massive amount of toxic substances and harmful chemicals are released every day into the outer environment, imposing serious environmental impacts on both land and aquatic animals. To date, research is constantly in progress to determine the best catalytic material for the effective remediation of these harmful pollutants. Hybrid nanomaterials prepared by combining functional polymers with inorganic nanostructures got attention as a promising area of research owing to their remarkable multifunctional properties deriving from their entire nanocomposite structure. The versatility of the existing nanomaterials' design in polymer-inorganic hybrids, with respect to their structure, composition, and architecture, opens new prospects for catalytic applications in environmental remediation. This review article provides comprehensive detail on catalytic polymer nanocomposites and highlights how they might act as a catalyst in the remediation of toxic pollutants. Additionally, it provides a detailed clarification of the processing of design and synthetic ways for manufacturing polymer nanocomposites and explores further into the concepts of precise design methodologies. Polymer nanocomposites are used for treating pollutants (electrocatalytic, biocatalytic, catalytic, and redox degradation). The three catalytic techniques that are frequently used are thoroughly illustrated. Furthermore, significant improvements in the method through which the aforementioned catalytic process and pollutants are extensively discussed. The final section summarizes challenges in research and the potential of catalytic polymer nanocomposites for environmental remediation.


Asunto(s)
Contaminantes Ambientales , Restauración y Remediación Ambiental , Nanocompuestos , Polímeros , Restauración y Remediación Ambiental/métodos , Catálisis , Polímeros/química , Contaminantes Ambientales/química , Nanocompuestos/química , Oxidación-Reducción
15.
Int J Biol Macromol ; 274(Pt 2): 133379, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38936571

RESUMEN

Chitin is the second most abundant natural biopolymer, which is composed of N-acetyl glucosamine units linked by ß-(1 â†’ 4) Chitosan is an N-deacetylated product of chitin. Properties of chitosan and chitin, such as biocompatibility, non-toxic nature, and biodegradability, make them successful alternatives for energy and environmental applications. However, their low mechanical properties, small surface area, reduced thermal properties, and greater pore volume restrict the potential for adsorption applications. Multiple investigations have demonstrated that these flaws can be prevented by fabricating chitosan and chitin with carbon-based composites. This review presents a comprehensive analysis of the fabrication of chitosan/chitin carbon-based materials. Furthermore, this review examines the prevalent technologies of functionalizing chitosan/chitin biopolymers and applications of chitin and chitosan as well as chitosan/chitin carbon-based composites, in various environmental fields (mitigating diverse water contaminants and developing biosensors). Also, the subsequent regeneration and reuse of adsorbents were also discussed. Finally, we summarize a concise overview of the difficulties and potential opportunities associated with the utilization of chitosan/chitin carbon-based composites as adsorbents to remove water contaminants.


Asunto(s)
Carbono , Quitina , Quitosano , Adsorción , Quitosano/química , Carbono/química , Quitina/química , Biopolímeros/química , Contaminantes Químicos del Agua/química , Purificación del Agua/métodos
16.
Med Phys ; 2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38896829

RESUMEN

BACKGROUND: Head and neck (HN) gross tumor volume (GTV) auto-segmentation is challenging due to the morphological complexity and low image contrast of targets. Multi-modality images, including computed tomography (CT) and positron emission tomography (PET), are used in the routine clinic to assist radiation oncologists for accurate GTV delineation. However, the availability of PET imaging may not always be guaranteed. PURPOSE: To develop a deep learning segmentation framework for automated GTV delineation of HN cancers using a combination of PET/CT images, while addressing the challenge of missing PET data. METHODS: Two datasets were included for this study: Dataset I: 524 (training) and 359 (testing) oropharyngeal cancer patients from different institutions with their PET/CT pairs provided by the HECKTOR Challenge; Dataset II: 90 HN patients(testing) from a local institution with their planning CT, PET/CT pairs. To handle potentially missing PET images, a model training strategy named the "Blank Channel" method was implemented. To simulate the absence of a PET image, a blank array with the same dimensions as the CT image was generated to meet the dual-channel input requirement of the deep learning model. During the model training process, the model was randomly presented with either a real PET/CT pair or a blank/CT pair. This allowed the model to learn the relationship between the CT image and the corresponding GTV delineation based on available modalities. As a result, our model had the ability to handle flexible inputs during prediction, making it suitable for cases where PET images are missing. To evaluate the performance of our proposed model, we trained it using training patients from Dataset I and tested it with Dataset II. We compared our model (Model 1) with two other models which were trained for specific modality segmentations: Model 2 trained with only CT images, and Model 3 trained with real PET/CT pairs. The performance of the models was evaluated using quantitative metrics, including Dice similarity coefficient (DSC), mean surface distance (MSD), and 95% Hausdorff Distance (HD95). In addition, we evaluated our Model 1 and Model 3 using the 359 test cases in Dataset I. RESULTS: Our proposed model(Model 1) achieved promising results for GTV auto-segmentation using PET/CT images, with the flexibility of missing PET images. Specifically, when assessed with only CT images in Dataset II, Model 1 achieved DSC of 0.56 ± 0.16, MSD of 3.4 ± 2.1 mm, and HD95 of 13.9 ± 7.6 mm. When the PET images were included, the performance of our model was improved to DSC of 0.62 ± 0.14, MSD of 2.8 ± 1.7 mm, and HD95 of 10.5 ± 6.5 mm. These results are comparable to those achieved by Model 2 and Model 3, illustrating Model 1's effectiveness in utilizing flexible input modalities. Further analysis using the test dataset from Dataset I showed that Model 1 achieved an average DSC of 0.77, surpassing the overall average DSC of 0.72 among all participants in the HECKTOR Challenge. CONCLUSIONS: We successfully refined a multi-modal segmentation tool for accurate GTV delineation for HN cancer. Our method addressed the issue of missing PET images by allowing flexible data input, thereby providing a practical solution for clinical settings where access to PET imaging may be limited.

17.
iScience ; 25(10): 105062, 2022 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-36157591

RESUMEN

At the Arabidopsis shoot apex, epidermal cells are planar-polarized along an axis marked by the asymmetric localization patterns of several proteins including PIN-FORMED1 (PIN1), which facilitates the directional efflux of the plant hormone auxin to pattern phyllotaxis. While PIN1 polarity is known to be regulated non-cell autonomously via the MONOPTEROS (MP) transcription factor, how this occurs has not been determined. Here, we use mosaic expression of the serine threonine kinase PINOID (PID) to test whether PIN1 polarizes according to the polarity of neighboring cells. Our findings reveal that PIN1 is insensitive to the polarity of PIN1 in neighboring cells arguing against auxin flux or extracellular auxin concentrations acting as a polarity cue, in contrast to previous model proposals.

18.
ACS Omega ; 7(48): 43883-43893, 2022 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-36506218

RESUMEN

In the present work, we report the synthesis of wurtzite CuGaS2 and its composite with MoS2 and explored their efficacy toward two important applications, viz. electrocatalytic hydrogen evolution reaction (HER) and adsorption of Rhodamine B dye. The CuGaS2 was synthesized via a low-temperature ethylenediamine-mediated solvothermal method. The obtained products were characterized by various techniques such as X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy to ascertain the phase formation, surface morphology, and elemental oxidation states. The electrocatalytic activity of the wurtzite CuGaS2 and CuGaS2/MoS2 composites toward HER was investigated, wherein the CuGaS2/MoS2 composite exhibited superior activity when compared to the pristine sample with a small Tafel slope of 56.2 mV dec-1 and an overpotential value of -464 mV at the current density of 10 mA cm-2. On the other hand, the synthesized CuGaS2 also showed an impressive adsorption behavior toward Rhodamine B dye with 99% adsorption in 60 min, which is relatively better than that observed with the composite material.

19.
Int J Public Health ; 67: 1604375, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35872706

RESUMEN

Objectives: The study aimed to evaluate the availability, prices, and affordability of selected essential medicines in Balochistan, Pakistan. Methods: Cross-sectional research was conducted in several cities of Balochistan, Pakistan, using the World Health Organization/Health Action International methodology to assess the availability and cost of 50 originator brand (OB) and lowest priced generic (LPG) drugs. The medicine costs were compared to international reference prices (IRPs) to calculate the median price ratio. The daily wage of the lowest paid unskilled government employee was used to determine affordability. Results: The mean availability was low for OBs (9.8%) and fairly high (49.4%) for LPGs. The OBs and LPGs' mean availability in the private sector were fairly high, 51.8% and 42.6%, respectively. It was surprising to see that Balochistan's public sector has only 24.3% of the National Essential Medicine List when the medicines on this list are supposed to be adequately available. Conclusion: The standard treatment cost with OBs is steep, exceeding the minimum daily wage. Treatment with LPG medications seems affordable. Furthermore, essential LPG medicines are economical when used solely for medication therapy.


Asunto(s)
Medicamentos Esenciales , Accesibilidad a los Servicios de Salud , Costos y Análisis de Costo , Estudios Transversales , Medicamentos Genéricos , Humanos , Pakistán
20.
Saudi J Biol Sci ; 29(1): 436-443, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35002439

RESUMEN

Cardiovascular diseases (CVD) are the leading cause of death all over the world. Beside general risk factors, there are some genetic factors which lead to cardiovascular diseases. Various nuclear DNA mutation and also mitochondrial DNA mutations have been related with cardiovascular diseases. In the present study, a total of 21 samples were collected from different families residing in district Dir. DNA was extracted from buccal epithelial cells using saliva. The mitochondrial tRNA leu (MT TL1) gene was amplified by PCR and 10 samples of different families were sequenced. The sequence was aligned with revised Cambridge Reference Sequence (rCRS) accession # NC-012920.1. It is concluded that cardiovascular diseases in our subjects are not due to mutation in the mitochondrial leucine tRNA gene. However, a large population of subjects with cardiovascular diseases needs to be studied and whole mitochondrial DNA is needed to be sequenced in the subjects with CVD. This will give an idea about the probable DNA marker which can be used to prevent loses due to these diseases at a very early stages.

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