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1.
Gen Comp Endocrinol ; : 114600, 2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-39209004

RESUMEN

Peptide YY (PYY) is an anorectic brain-gut pancreatic peptide that helps in feeding regulation by reducing appetite and is well characterized in mammals. The role of PYY in relation to brain is least studied in mammals as well as in lower vertebrates including fish, however high expression was evident in male reproductive tissue. In this regard, this study attempts to evaluate the significance of PYY in the brain of common carp, Cyprinus carpio. As a first step, the cDNA of PYY from brain of adult male carp was subcloned. Following which expression analysis was performed using juvenile and adult fish. The differential distribution pattern in various regions of brain and ontogeny expression analysis indicate that PYY may involve in physiological processes related to brain-pituitary axis. In addition, a significant decrease in neuropeptides Y expression was observed upon PYY- endoribonuclease-prepared small interfering RNA transfection in brain cells, in vitro indicating their plausible PYY-NPY interaction.

2.
Nanotechnology ; 31(49): 495301, 2020 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-32975218

RESUMEN

In this paper, a wet-dry hybrid technique to transfer patterned reduced graphene oxide (rGO) thin film to arbitrary substrates at predetermined locations without using any chemicals is reported. The transfer process involves water-assisted delamination of rGO, followed by dry transfer to an acceptor substrate using viscoelastic stamp. Patterned reduced graphene oxide films are transferred to silicon dioxide (SiO2/Si) substrate to begin with. Subsequently, the method is deployed to transfer rGO to different polymer substrates such as poly(methyl methacrylate) (PMMA), and crosslinked poly(4-vinylphenol) (c-PVP), which are commonly used as gate dielectric in flexible electronic applications. The credibility of the transfer process with precise spatial positioning on the target substrate leads to fabrication of freely suspended reduced graphene oxide membrane towards nanoelectromechanical systems (NEMS) based devices such as nanomechanical drum resonators.

3.
J Exp Biol ; 222(Pt 8)2019 04 18.
Artículo en Inglés | MEDLINE | ID: mdl-30936270

RESUMEN

The capacity and condition under which the lateral transfer of olfactory memory is possible in insects is still debated. Here, we present evidence in two species of honeybees, Apis mellifera and Apis dorsata, consistent with the lack of ability to transfer olfactory associative memory in a proboscis extension response (PER) associative conditioning paradigm, where the untrained antenna is blocked by an insulating coat. We show that the olfactory system on each side of the bee can learn and retrieve information independently and the retrieval using the antenna on the side contralateral to the trained one is not affected by the training. Using the setup in which the memory on the contralateral side has been reported at 3 h after training, we see that the memory is available on the contralateral side immediately after training. In the same setup, coating the antenna with an insulator on the training side does not prevent learning, pointing to a possible insufficiency of the block of odor stimuli in this setup. Moreover, the behavior of the bee as a whole can be predicted if the sides are assumed to learn and store independently, and the organism as a whole is able to retrieve the memory if either of the sides have the memory.


Asunto(s)
Abejas/fisiología , Olfato/fisiología , Animales , Aprendizaje por Asociación/fisiología , Memoria/fisiología
4.
J Natl Compr Canc Netw ; 17(4): 367-402, 2019 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-30959471

RESUMEN

The NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Cutaneous melanoma have been significantly revised over the past few years in response to emerging data on immune checkpoint inhibitor therapies and BRAF-targeted therapy. This article summarizes the data and rationale supporting extensive changes to the recommendations for systemic therapy as adjuvant treatment of resected disease and as treatment of unresectable or distant metastatic disease.


Asunto(s)
Oncología Médica , Melanoma , Neoplasias Cutáneas , Humanos , Oncología Médica/normas , Melanoma/diagnóstico , Neoplasias Cutáneas/diagnóstico , Melanoma Cutáneo Maligno
5.
Trop Med Int Health ; 23(4): 405-414, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29430785

RESUMEN

OBJECTIVES: To develop and implement a community-based programme for screening of diabetic retinopathy (DR) in urban populations of Delhi. METHODS: Known diabetics (KDs) aged 40 years and older were identified through house-to-house surveys, volunteers and publicity. All KDs were referred to DR screening camps organised locally where procedures included brief medical history, ocular examination and non-mydriatic fundus photography using portable handheld camera. Fundal images were graded on the spot by trained optometrists for DR. Patients with DR were referred to tertiary centre for management. RESULTS: A total of 11 566 KDs were identified, of whom 9435 (81.6%) visited DR screening camps and 8432 (89.4%) had DR gradable images. DR was identified in 13.5% of subjects; 351 cases were mild NPDR, 567 moderate, 92 severe. Seventy-seven had PDR, and 49 had DME, and 2.7% of participants were blind (presenting visual acuity <3/60 in better eye). Non-use of lifestyle management, presence of systemic complications, BMI <18.5 kg/m2 , disease duration of >5 years and uncontrolled diabetes were associated with increased odds of DR. All cases with DR were referred, and 420 (37%) successful referrals to base hospital were observed. CONCLUSION: The programme of creating awareness about DR, identifying KDs and optometrist-led DR screening using non-mydriatic fundus camera based in slums was successful.


Asunto(s)
Retinopatía Diabética/diagnóstico , Fondo de Ojo , Tamizaje Masivo/métodos , Fotograbar , Áreas de Pobreza , Pobreza , Población Urbana , Adulto , Anciano , Ceguera/epidemiología , Ceguera/etiología , Índice de Masa Corporal , Ciudades , Diabetes Mellitus , Retinopatía Diabética/diagnóstico por imagen , Retinopatía Diabética/epidemiología , Manejo de la Enfermedad , Femenino , Humanos , India , Masculino , Persona de Mediana Edad , Midriáticos , Derivación y Consulta , Retina/patología , Factores de Riesgo , Agudeza Visual
6.
Gen Comp Endocrinol ; 251: 54-65, 2017 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-28322767

RESUMEN

Neuropeptide-Y (NPY) has diverse physiological functions which are extensively studied in vertebrates. However, regulatory role of NPY in relation to brain ontogeny and recrudescence with reference to reproduction is less understood in fish. Present report for the first time evaluated the significance of NPY by transient esiRNA silencing and also analyzed its expression during brain development and gonadal recrudescence in the catfish, Clarias gariepinus. As a first step, full-length cDNA of NPY was cloned from adult catfish brain, which shared high homology with its counterparts from other teleosts upon phylogenetic analysis. Tissue distribution revealed dominant expression of NPY in brain and testis. NPY expression increased during brain development wherein the levels were higher in 100 and 150days post hatch females than the respective age-matched males. Seasonal cycle analysis showed high expression of NPY in brain during pre-spawning phase in comparison with other reproductive phases. Localization studies exhibited the presence of NPY, abundantly, in the regions of preoptic area, hypothalamus and pituitary. Transient silencing of NPY-esiRNA directly into the brain significantly decreased NPY expression in both the male and female brain of catfish which further resulted in significant decrease of transcripts of tryptophan hydroxylase 2, catfish gonadotropin-releasing hormone (cfGnRH), tyrosine hydroxylase and 3ß-hydroxysteroid dehydrogenase in brain and luteinizing hormone-ß/gonadotropin-II (lh-ß/GTH-II) in pituitary exhibiting its influence on gonadal axis. In addition, significant decrease of several ovary-related transcripts was observed in NPY-esiRNA silenced female catfish, indicating the plausible role of NPY in ovary through cfGnRH-GTH axis.


Asunto(s)
Encéfalo/embriología , Bagres/embriología , Bagres/genética , Regulación del Desarrollo de la Expresión Génica , Gónadas/embriología , Neuropéptido Y/genética , Secuencia de Aminoácidos , Animales , Encéfalo/metabolismo , Clonación Molecular , ADN Complementario/genética , Femenino , Perfilación de la Expresión Génica , Silenciador del Gen , Gónadas/metabolismo , Inmunohistoquímica , Hibridación in Situ , Masculino , Neuropéptido Y/metabolismo , Ovario/metabolismo , Filogenia , Hipófisis/metabolismo , Polietileneimina , ARN Mensajero/genética , ARN Mensajero/metabolismo , Recurrencia , Reproducción , Alineación de Secuencia
7.
J Natl Compr Canc Netw ; 14(8): 945-58, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27496110

RESUMEN

The NCCN Guidelines for Melanoma have been significantly revised over the past few years in response to emerging data on a number of novel agents and treatment regimens. These NCCN Guidelines Insights summarize the data and rationale supporting extensive changes to the recommendations for systemic therapy in patients with metastatic or unresectable melanoma.


Asunto(s)
Melanoma/diagnóstico , Melanoma/terapia , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Terapia Combinada , Humanos , Inmunoterapia , Melanoma/etiología , Terapia Molecular Dirigida , Estadificación de Neoplasias , Retratamiento , Resultado del Tratamiento
8.
Nanotechnology ; 26(49): 495701, 2015 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-26572253

RESUMEN

Graphene, the thinnest possible anticorrosion and gas-permeation barrier, is poised to transform the protective coatings industry for a variety of surface applications. In this work, we have studied the structural changes of graphene when the underlying copper surface undergoes oxidation upon heating. Single-layer graphene directly grown on a copper surface by chemical vapour deposition was annealed under ambient atmosphere conditions up to 400 °C. The onset temperature of the surface oxidation of copper is found to be higher for graphene-coated foils. Parallel arrays of graphene nanoripples are a ubiquitous feature of pristine graphene on copper, and we demonstrate that these form crucial sites for the onset of the oxidation of copper, particularly for ∼0.3-0.4 µm ripple widths. In these regions, the oxidation proceeds along the length of the nanoripples, resulting in the formation of parallel stripes of oxidized copper regions. We demonstrate from temperature-dependent Raman spectroscopy that the primary defect formation process in graphene involves boundary-type defects rather than vacancy or sp(3)-type defects. This observation is consistent with a mechanical tearing process that splits graphene into small polycrystalline domains. The size of these is estimated to be sub-50 nm.

9.
J Invertebr Pathol ; 132: 157-164, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26455997

RESUMEN

Balance between reactive oxygen species (ROS) and the antioxidant (AO) defense mechanisms is vital for organism survival. Insects serve as an ideal model to elucidate oxidative stress responses as they are prone to different kinds of stress during their life cycle. The present study demonstrates the modulation of AO enzyme gene expression in the insect pest, Achaea janata (castor semilooper), when subjected to different oxidative stress stimuli. Antioxidant enzymes' (catalase (Cat), superoxide dismutase (Sod), glutathione-S-transferase (GST) and glutathione peroxidase (Gpx)) partial coding sequences were cloned and characterized from larval whole body. Tissue expression studies reveal a unique pattern of AO genes in the larval tissues with maximum expression in the gut and fat body. Ontogeny profile depicts differential expression pattern through the larval developmental stages for each AO gene studied. Using quantitative RT-PCR, the expression pattern of these genes was monitored during sugar-induced (d-galactose feeding), infection-induced (Gram positive, Gram negative and non-pathogenic bacteria) and pesticide-induced oxidative stress (Bt Cry toxin). d-Galactose feeding differentially modulates the expression of AO genes in the larval gut and fat body. Immune challenge with Escherichia coli induces robust upregulation of AO genes when compared to Bacillus coagulans and Bacillus cereus in the larval fat body and gut. Cry toxin feeding predominantly induced GST upregulation in the gut. The current study suggests that though there are multiple ways of generation of oxidative stress in the insect, the organism tailors its response by insult- and tissue-specific recruitment of the antioxidant players and their differential regulation for each inducer.


Asunto(s)
Mariposas Nocturnas/fisiología , Estrés Oxidativo , Secuencia de Aminoácidos , Animales , Antioxidantes/metabolismo , Catalasa/genética , Catalasa/metabolismo , Clonación Molecular , Escherichia coli/inmunología , Regulación de la Expresión Génica , Glutatión Peroxidasa/genética , Glutatión Peroxidasa/metabolismo , Glutatión Transferasa/genética , Glutatión Transferasa/metabolismo , Mariposas Nocturnas/genética , Mariposas Nocturnas/inmunología , Especies Reactivas de Oxígeno/metabolismo , Alineación de Secuencia , Análisis de Secuencia de Proteína , Superóxido Dismutasa/genética , Superóxido Dismutasa/metabolismo
10.
J Biol Chem ; 288(6): 4321-33, 2013 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-23209296

RESUMEN

Recent studies of epithelial tissues have revealed the presence of tissue-specific stem cells that are able to establish multiple cell lineages within an organ. The stem cells give rise to progenitors that replicate before differentiating into specific cell lineages. The mechanism by which homeostasis is established between proliferating stem or progenitor cells and terminally differentiated cells is unclear. This study demonstrates that Agr2 expression by mucous neck cells in the stomach promotes the differentiation of multiple cell lineages while also inhibiting the proliferation of stem or progenitor cells. When Agr2 expression is absent, gastric mucous neck cells increased in number as does the number of proliferating cells. Agr2 expression loss also resulted in the decline of terminally differentiated cells, which was supplanted by cells that exhibited nuclear SOX9 labeling. Sox9 expression has been associated with progenitor and stem cells. Similar effects of the Agr2 null on cell proliferation in the intestine were also observed. Agr2 consequently serves to maintain the balance between proliferating and differentiated epithelial cells.


Asunto(s)
Diferenciación Celular , Linaje de la Célula , Regulación del Desarrollo de la Expresión Génica , Mucoproteínas/biosíntesis , Células Madre/metabolismo , Estómago/embriología , Animales , Proliferación Celular , Hiperplasia , Ratones , Ratones Mutantes , Mucoproteínas/genética , Proteínas Oncogénicas , Factor de Transcripción SOX9/genética , Factor de Transcripción SOX9/metabolismo , Células Madre/patología , Estómago/patología
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