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1.
Langmuir ; 40(18): 9481-9489, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38650463

RESUMEN

Herein, we have isolated onion-like nanocarbon (ONC) from the exhaust soot of diesel engines and further doped it with nitrogen (N) and sulfur (S) to fabricate N,S-co-doped ONC (N-S-ONC). To explore its application feasibility, we have assembled an aqueous Zn-ion hybrid supercapacitor (ZIHSC) with a N-S-ONC cathode, which attains high specific capacitance with good rate capability. In-depth analyses suggest that the mechanism of charge storage in the ONC is governed by both capacitive-controlled and diffusion-controlled processes, with the capacitive processes leading at all sweep rates. The ZIHSC demonstrated a good energy density of 50 Wh/kg, a maximum power density of 3.6 kW/kg, and an impressive cycle life with 73% capacitance retention after 50,000 charge-discharge cycles. The study suggests the potential possibly for the long-term application of BC derived nanocarbon in electrochemical energy storage systems (EESSs).

2.
Langmuir ; 40(19): 9855-9872, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38687994

RESUMEN

Two-dimensional (2D) layered materials like graphene, transition-metal dichalcogenides (TMDs), boron nitrides, etc., exhibit unique and fascinating properties, such as high surface-to-volume ratio, inherent mechanical flexibility and robustness, tunable bandgap, and high carrier mobility, which makes them an apt candidate for flexible electronics with low consumption of power. Because of these properties, they are in tremendous demand for advancement in energy, environmental, and biomedical sectors developed through various technologies. The production and scalability of these materials must be sustainable and ecofriendly to utilize these unique properties in the real world. Here, in this current review, we review molybdenum disulfide (MoS2 nanosheets) in detail, focusing on exfoliated MoS2 in water and the applicability of aqueous MoS2 suspensions in various fields. The exfoliation of MoS2 results in the formation of single or few-layered MoS2. Therefore, this Review focuses on the few layers of exfoliated MoS2 that have the additional properties of 2D layered materials and higher excellent compatibility for integration than existing conventional Si tools. Hence, a few layers of exfoliated MoS2 are widely explored in biosensing, gas sensing, catalysis, photodetectors, energy storage devices, a light-emitting diode (LED), adsorption, etc. This review covers the numerous methodologies to exfoliate MoS2, focusing on the various published methodologies to obtain nanosheets of MoS2 from water solutions and their use.

3.
Environ Res ; 212(Pt B): 113308, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35460637

RESUMEN

Herein, a simple-functionalization method is described to prepare the oleylamine functionalized non-aqueous version of onion-like nanocarbons (ONC-OA), where ONC was isolated from the waste pollutant soot exhausted from the diesel engine. The surface group analysis of ONC-OA has been investigated via Nuclear Magnetic Resonance and X-ray Photoelectron Spectroscopy. ONC-OA shows blue fluorescence with a quantum yield of ∼6% in tetrahydrofuran (THF). The fluorescence-based sensing applications of ONC-OA has been investigated for selective sensing of toxic aromatic nitro-phenols compounds (para-nitro, dinitro, and trinitro phenols) from the tested many nitro organic compounds. Based on the limit of detection values, ONC-OA shows much better results for tri-nitro phenol compared to di and mono nitrophenol. To understand the quenching mechanism, a time-resolved photoluminescence analysis of the sensor with and without the addition of quenchers is performed. The effective lowering in fluorescence lifetime of the sensor after the addition of quenchers concludes that the quenching observed is majorly due to the Förster Resonance Energy Transfer (FRET) mechanism. The real-life application of ONC-OA was analyzed by external spiking of N-PhOHs in soil samples.


Asunto(s)
Transferencia Resonante de Energía de Fluorescencia , Hollín , Carbono/química , Cebollas , Fenoles
4.
Chemosphere ; 287(Pt 3): 132287, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34563775

RESUMEN

A scalable synthetic procedure for fabricating photoactive carbon dots (CD) from microcrystalline cellulose (MCC) is presented. The MCC was transformed into a photoactive nanosized CD by a one-step acid-assisted thermal-carbonization (~90 °C for 30 min). The efficiency of the obtained CD was determined by photo-removal of toxic hexavalent chromium (Cr(VI)) ions from wastewater. CD obtained from cellulose completely removed 20 ppm of Cr(VI) wastewater within ∼120 min under sunlight illumination. No Cr(VI) removal was observed in dark conditions and with control cellulose material as reference samples. The Cr(VI) removal follows pseudo-first-order kinetics along with a half-life of ∼26 min. Furthermore, the Cr(VI) removal from wastewater was supported via cyclic voltammetry analysis. Using a low-cost, naturally available cellulose material and sulfuric acid, the world's most-used chemical, creates techno-economic prerequisites for a scalable process of photoactive carbon dots.


Asunto(s)
Contaminantes Químicos del Agua , Purificación del Agua , Adsorción , Carbono , Celulosa , Cromo/análisis , Concentración de Iones de Hidrógeno , Cinética , Luz Solar , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidad
5.
BMJ Case Rep ; 14(7)2021 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-34326119

RESUMEN

Coexistence of idiopathic Parkinson's disease (iPD) and schizophrenia can pose great diagnostic and therapeutic challenges because of their pathophysiology. Our case highlights such challenges in management. We present a case of 73-year-old man who had parkinsonism for last several years and was also diagnosed with schizophrenia. Due to lack of collateral information about the onset of symptoms and clinical course, it was difficult to distinguish iPD from neuroleptic-induced parkinsonism. Even though, certain clinical findings may help to differentiate between the two conditions, single positron emission computerized tomography/DatScan was used to confirm the diagnosis of iPD. Treatment of coexisting iPD and schizophrenia can be challenging, and a delicate pharmacologic balance must be maintained to ensure adequate symptomatic control. Current evidence suggests that clozapine is a better choice for managing psychosis in these patients due to its unique receptor profile and better safety data.


Asunto(s)
Clozapina , Enfermedad de Parkinson Secundaria , Enfermedad de Parkinson , Esquizofrenia , Anciano , Clozapina/efectos adversos , Humanos , Masculino , Enfermedad de Parkinson/complicaciones , Enfermedad de Parkinson/diagnóstico , Enfermedad de Parkinson/tratamiento farmacológico , Tomografía de Emisión de Positrones , Esquizofrenia/complicaciones , Esquizofrenia/diagnóstico , Esquizofrenia/tratamiento farmacológico
6.
Nanoscale Adv ; 1(11): 4481-4491, 2019 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-36134401

RESUMEN

Non-toxic amine-functionalized soluble graphene nano-sheets (f-GNS) were synthesized by using an old and well-known simple organic procedure. The f-GNS exhibited enhanced optical properties, such as strong blue fluorescence emission with a high value of quantum yield (∼13%). The O,O'-bis-(2-aminopropyl) polypropylene glycol-block-polyethylene glycol-block-polypropylene glycol 800 as block polymeric amine (BPA)-passivized surface of f-GNS exhibited high aqueous solubility and excitation-dependent fluorescence emission behavior with a strong photo-stability performance. These f-GNS were tested for the significant selective sensing of toxic metal ions Cr(vi) and Hg(ii) from various tested toxic metal ions. The sensing experiment was supported by cyclic voltammetry analysis. The dual metal ion sensing method based on fluorescence showed the limit of detection (LOD) of ∼56 nM for Cr(vi) and ∼45 nM for Hg(ii) through a fluorescence quenching process. f-GNS were found to be non-toxic when tested over Escherichia coli (E.coli) cells. Additionally, the strong blue emission properties of f-GNS enabled their use as a suitable blue fluorescent ink under UV light illumination.

7.
J Oral Maxillofac Pathol ; 22(Suppl 1): S44-S47, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29491604

RESUMEN

Melanotic neuroectodermal tumor of infancy is a rare benign but locally aggressive neoplasm of neural crest origin with a high recurrence rate. It usually affects infants of < 1 year of age. Involvement of maxilla of an infant is the most common presentation although cases outside this setting have been reported. We report the case of a 6-month-old male child presenting with intraoral swelling. Radiologically, a tumor was detected in the right maxilla, and wide local excision was done. Histological examination revealed typical biphasic population of cells with deposits of melanin pigment. Immunohistochemistry study was done confirming the diagnosis.

8.
Cytokine ; 96: 247-252, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28486207

RESUMEN

BACKGROUND: Cytokines are of increasing interest as markers for stress responses, mental disorders and general health. We assessed associations of two cytokines with several factors among relocated hurricane survivors and controls. METHODS: We examined 40 relocated hurricane survivors and 40 demographically matched (frequency matching) Oklahoma controls to assess relationships of Interleukin-2 (IL-2) and Interleukin-6 (IL-6) with psychiatric diagnoses (SCID-IV), demographic variables, hurricane exposure and body mass index (BMI). Participants were predominantly African American (n=70, 87.5%). RESULTS: Relocated Katrina survivors had higher proportions of current PTSD, major depression and psychiatric diagnoses than controls. Unexpectedly, exposure to Katrina with relocation was not by itself associated with differences in IL-2 or IL-6 levels. The mean IL-2 level was significantly higher in African American participants than other ethnicities (8 Caucasians, 2 Asians) and in those with a current psychiatric disorder. The mean IL-6 level was higher in females than males and in participants with any current psychiatric diagnosis. IL-6 level also correlated positively with participants' BMI. CONCLUSIONS: Results suggest that cytokines studied were influenced non-specifically by the presence of a mental disorder, and by demographic variables of gender, ethnicity and BMI. Implications of these findings are discussed, as well as possible long-term impact of the identified interleukin differences on immunologic, inflammatory, neuropsychiatric and other systems.


Asunto(s)
Índice de Masa Corporal , Trastorno Depresivo Mayor/inmunología , Interleucina-2/sangre , Interleucina-6/sangre , Trastornos Mentales , Trastornos por Estrés Postraumático/inmunología , Adolescente , Adulto , Negro o Afroamericano/psicología , Negro o Afroamericano/estadística & datos numéricos , Biomarcadores/sangre , Tormentas Ciclónicas , Trastorno Depresivo Mayor/sangre , Trastorno Depresivo Mayor/diagnóstico , Trastorno Depresivo Mayor/etnología , Etnicidad , Femenino , Humanos , Interleucina-2/inmunología , Interleucina-6/inmunología , Masculino , Trastornos Mentales/etnología , Trastornos Mentales/inmunología , Persona de Mediana Edad , Trastornos por Estrés Postraumático/sangre , Trastornos por Estrés Postraumático/diagnóstico , Trastornos por Estrés Postraumático/etnología , Estrés Psicológico/sangre , Estrés Psicológico/diagnóstico , Estrés Psicológico/etnología , Estrés Psicológico/inmunología , Sobrevivientes/psicología , Sobrevivientes/estadística & datos numéricos , Adulto Joven
9.
Focus (Am Psychiatr Publ) ; 15(2): 157-161, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31975848

RESUMEN

The spectrum of anxiety disorders occurring in later life is diverse and includes the same disorders that occur with younger adults-such as generalized anxiety disorder, panic disorder, specific phobias, and social anxiety disorder-but also unique presentations, including a fear of falling and the anxiety often seen in various neurocognitive disorders. Therefore, diagnosis and treatment are arguably more challenging in older populations. In addition, many older adults have subthreshold symptoms that can benefit from proper management. This article summarizes the literature on anxiety disorder presentations in later life and offers key recommendations to assist clinicians working with this growing population.

10.
Popul Health Manag ; 19(S3): S1-S8, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27834576

RESUMEN

Medicare Advantage: Issues, Insights, and Implications for the Future Paul Cotton, Joseph P. Newhouse, PhD, Kevin G. Volpp, MD, PhD, A. Mark Fendrick, MD, Susan Lynne Oesterle, Pat Oungpasuk, Ruchi Aggarwal, Gail Wilensky, PhD, and Kathleen Sebelius Editorial S-2 D.B. Nash, and A.Y. Schwartz The History, Impact, and Future of the Medicare Advantage Star Ratings System S-3 P. Cotton Medicare Advantage and Traditional Fee-For-Service Medicare S-4 J.P. Newhouse Behavioral Economics: Key to Effective Care Management Programs for Patients, Payers, and Providers S-5 K.G. Volpp Value-Based Insurance Design: A Promising Strategy for Medicare Advantage S-6 A.M. Fendrick, S.L. Oesterle, P. Oungpasuk, and R. Aggarwal Two Perspectives on the Future of Medicare Advantage S-7 G. Wilensky and K. Sebelius.


Asunto(s)
Planes de Aranceles por Servicios/tendencias , Medicare Part C/tendencias , Mejoramiento de la Calidad , Humanos , Estados Unidos
11.
Biochemistry (Mosc) ; 80(8): 972-89, 2015 08.
Artículo en Inglés | MEDLINE | ID: mdl-26547065

RESUMEN

The hallmarks of carcinogenesis are characterized by alterations in the expression of multiple genes that occur via genetic and epigenetic alterations, leading to genome rearrangements and instability. The reversible process of epigenetic regulation, which includes changes in DNA methylation, histone modifications, and alteration in microRNA (miRNA) expression that alter phenotype without any change in the DNA sequence, is recognized as a key mechanism in cancer cell metabolism. Recent advancements in the rapidly evolving field of cancer epigenetics have shown the anticarcinogenic potential of natural compounds targeting epigenetic mechanism as a common molecular approach for cancer treatment. This review summarizes the potential of natural chemopreventive agents to reverse cancer-related epigenetic aberrations by regulating the activity of histone deacetylases, histone acetyltransferases, DNA methyltransferase I, and miRNAs. Furthermore, there is impetus for determining novel and effective chemopreventive strategies, either alone or in combination with other anticancer agents that exhibit similar properties, for improving the therapeutic aspects of cancer.


Asunto(s)
Anticarcinógenos/farmacología , Antineoplásicos/uso terapéutico , Productos Biológicos/farmacología , Epigénesis Genética/efectos de los fármacos , Neoplasias/genética , Neoplasias/prevención & control , Humanos , Neoplasias/metabolismo
12.
Appl Biochem Biotechnol ; 177(3): 577-94, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26210787

RESUMEN

Oral squamous cell carcinoma (OSCC) is a multistep process which is modulated by several endogenous and environmental factors. Epigenetic changes have been found to be equally responsible for OSCC as genetic changes. A plethora of genes showing hypermethylation have been discovered in OSCC. Since these changes are reversible, a lot of emphasis is on using the natural compounds for their ability to cause demethylation which could lead to reactivation of the inactivated tumor suppressor genes. This review encompasses the promoter hypermethylation of tumor suppressor genes in OSCC and its possible reversal using natural compounds. In addition, new compounds which could be screened for their demethylating ability have also been proposed.


Asunto(s)
Antineoplásicos/farmacología , Productos Biológicos/farmacología , Carcinoma de Células Escamosas/tratamiento farmacológico , ADN (Citosina-5-)-Metiltransferasas/antagonistas & inhibidores , Inhibidores Enzimáticos/farmacología , Animales , Antineoplásicos/uso terapéutico , Productos Biológicos/uso terapéutico , Carcinoma de Células Escamosas/enzimología , Carcinoma de Células Escamosas/genética , Inhibidores Enzimáticos/uso terapéutico , Humanos , Neoplasias de la Boca/tratamiento farmacológico , Neoplasias de la Boca/enzimología , Neoplasias de la Boca/genética
13.
Acad Psychiatry ; 37(5): 313-6, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24026368

RESUMEN

OBJECTIVE: Residents are one of the prime sources of information and education for medical students. As an initial step in supporting residents as teachers, a baseline self-assessment of residents' knowledge, skills, attitudes, and values related to teaching was conducted among psychiatry and family medicine residents to compare and improve their confidence and skills as teachers. METHOD: Psychiatry residents (N=12) and family medicine residents (N=23) completed self-assessments of their knowledge, skills, attitudes, and values related to teaching. Residents also were asked to list steps used in the One-Minute Preceptor process and estimate the time each spent in teaching. Descriptive summary statistics were used for four main areas related to teaching; t-test and chi-square analyses were conducted to ascertain whether there was a significant difference in resident groups. RESULTS: In the current study, the perceived amount of time spent for teaching patients was significantly higher among family practice residents, whereas no group differences were found for time teaching medical students, peers, community members, non-physicians, or others. However, family medicine residents rated themselves higher than psychiatry residents in their understanding of their roles in teaching medical students and teaching patients. Also, family medicine residents' self-reported teaching skills were more advanced (82.4%) than psychiatry residents' (54.2%). They most likely applied at least two different teaching methods in inpatient and outpatient settings, as compared with psychiatry residents. No significant group differences were found in the other 15 items assessing teaching knowledge, skills, attitudes, and values. CONCLUSION: Results indicate that residents' knowledge, skills, attitudes, and values regarding teaching varies across institutions and training programs. The psychiatry residents in this study do not clearly understand their role as educators with patients and medical students; they have a less clear understanding of teaching techniques, and report spending less time educating patients than do family medicine residents. The differences might be due to different patient populations and treatment settings. The study suggests that psychiatry residents may have difficulty adapting the One-Minute Preceptor technique in psychiatric settings. Results serve as a benchmarking study in a performance-improvement program to enhance psychiatry residents' teaching skills.


Asunto(s)
Actitud del Personal de Salud , Educación de Pregrado en Medicina/estadística & datos numéricos , Medicina Familiar y Comunitaria/educación , Internado y Residencia/normas , Psiquiatría/educación , Enseñanza/estadística & datos numéricos , Educación de Pregrado en Medicina/métodos , Humanos , Autoevaluación (Psicología) , Encuestas y Cuestionarios
14.
Cent Nerv Syst Agents Med Chem ; 9(4): 295-9, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20021362

RESUMEN

A series of 4-aryl substituted semicarbazones of pyridyl carbaldehyde and pyridyl methyl ketone were designed and synthesized to meet the structural requirements essential for anticonvulsant activity. The structure of synthesized compounds were confirmed by IR spectroscopy, PMR spectroscopy and nitrogen estimation. All the compounds were evaluated for anticonvulsant activity and neurotoxicity. Anticonvulsant activity was determined after intraperitoneal (i.p.) administration to mice by maximal electroshock (MES) and subcutaneous metrazol (ScMet) induced seizure methods and minimal motor impairment was determined by rotorod test. Majority of compounds exhibited significant anticonvulsant activity after intraperitoneal administration. The results obtained showed that 85.7 % of the compounds afforded protection in the MES test and 64.2 % of the total compounds afforded protection in ScPTZ test. Some of them also showed good activity after oral administration. In this study (Methyl-4- pyridyl) ketone -N(4)- (p- chloro phenyl) substituted semicarbazone emerged as most active derivative showing activity at 100 mg/kg in both the test with prolonged duration of action. In the present study semicarbazones of pyridyl containing carbonyl compounds emerges as the lead molecule, showing broad spectrum of activity with low neurotoxicity and prolong duration of action on oral administration. Thus these may be utilized for the future development of novel anticonvulsants with broad spectrum of anticonvulsant activity.


Asunto(s)
Relación Dosis-Respuesta a Droga , Diseño de Fármacos , Evaluación Preclínica de Medicamentos , Inyecciones Intraperitoneales , Modelos Moleculares , Estructura Molecular , Síndromes de Neurotoxicidad , Pentilenotetrazol/uso terapéutico , Convulsiones/tratamiento farmacológico , Relación Estructura-Actividad , Animales , Anticonvulsivantes , Electrochoque , Ratones , Semicarbazonas
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