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1.
Phytother Res ; 38(3): 1695-1714, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38318763

RESUMEN

Withania somnifera, the plant named Indian ginseng, Ashwagandha, or winter cherry, has been used since ancient times to cure various health ailments. Withania somnifera is rich in constituents belonging to chemical classes like alkaloids, saponins, flavonoids, phenolic acids, and withanolides. Several chemotypes were identified based on their phytochemical composition and credited for their multiple bioactivities. Besides, exhibiting neuroprotective, immunomodulatory, adaptogenic, anti-stress, bone health, plant has shown promising anti-cancer properties. Several withanolides have been reported to play a crucial role in cancer; they target cancer cells by different mechanisms such as modulating the expression of tumor suppressor genes, apoptosis, telomerase expression, and regulating cell signaling pathway. Though, many treatments are available for cancer; however, to date, no assured reliable cure for cancer is made available. Additionally, synthetic drugs may lead to development of resistance in time; therefore, focus on new and natural drugs for cancer therapeutics may prove a longtime effective alternative. This current report is a comprehensive combined analysis upto 2023 with articles focused on bio-activities of plant Withania somnifera from various sources, including national and international government sources. This review focuses on understanding of various mechanisms and pathways to inhibit uncontrolled cell growth by W. somnifera bioactives, as reported in literature. This review provides a recent updated status of the W. somnifera on pharmacological properties in general and anti-cancer in particular and may provide a guiding resource for researchers associated with natural product-based cancer research and healthcare management.


Asunto(s)
Withania , Witanólidos , Witanólidos/farmacología , Withania/química , Extractos Vegetales/farmacología , Fitoquímicos
2.
Chem Biodivers ; : e202400891, 2024 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-38825847

RESUMEN

The utilization of natural materials for the synthesis of highly fluorescent carbon quantum dots (CQDs) presents a sustainable approach to overcome the challenges associated with traditional chemical precursors. Here, we report the synthesis of novel S,N-self-doped CQDs (S,N@CQDs) derived from asparagus officinalis herb. These S,N@CQDs exhibit 16.7% fluorescence quantum yield, demonstrating their potential in medical diagnostics. We demonstrate the efficacy of S,N@CQDs as luminescent probes for the detection of anti-pathogenic medications metronidazole (MTZ) and nitazoxanide (NTZ) over concentration ranges of 0.0-180.0 µM (with a limit of detection (LOD) of 0.064 µM) and 0.25-40.0 µM (LOD of 0.05 µM), respectively. The probes were successfully applied to determine MTZ and NTZ in medicinal samples, real samples, and spiked human plasma, with excellent recovery rates ranging from 99.82% to 103.03%. Additionally, S,N@CQDs demonstrate exceptional efficacy as diagnostic luminescent probes for hemoglobin (Hb) detection over a concentration range of 0-900 nM, with a minimal detectability of 9.24 nM, comparable to commercially available medical laboratory diagnostic tests. The eco-friendly synthesis and precise detection limits of S,N@CQDs meet necessary analytical requirements and hold promise for advancing diagnostic capabilities in clinical settings. This research signifies a significant step towards sustainable and efficient fluorescence-based medical diagnostics.

3.
Arch Pharm (Weinheim) ; 357(4): e2300503, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38251950

RESUMEN

A series of 1,1'-biphenyl-3-carboxamide and furan-phenyl-carboxamide analogs were synthesized using an optimized scheme and confirmed by 1H and 13C nuclear magnetic resonance and high-resolution mass spectrometry techniques. The synthesized peptidomimetics analogs were screened in vitro to understand the inhibitory potential of pancreatic lipase (PL). Analogs were assessed for the PL inhibitory activity based on interactions, geometric complementarity, and docking score. Among the synthesized analogs, 9, 29, and 24 were found to have the most potent PL inhibitory activity with IC50 values of 3.87, 4.95, and 5.34 µM, respectively, compared to that of the standard drug, that is, orlistat, which inhibits PL with an IC50 value of 0.99 µM. The most potent analog, 9, exhibited a competitive-type inhibition with an inhibition constant (Ki) of 2.72 µM. In silico molecular docking of analog 9 with the PL (PDB ID:1LPB) showed a docking score of -11.00 kcal/mol. Analog 9 formed crucial hydrogen bond interaction with Ser152, His263, π-cation interaction with Asp79, Arg256, and π-π stacking with Phe77, Tyr114 at the protein's active site. The molecular dynamic simulation confirmed that analog 9 forms stable interactions with PL at the end of 200 ns with root mean square deviation values of 2.5 and 6 Å. No toxicity was observed for analog 9 (concentration range of 1-20 µM) when tested by MTT assay in RAW 264.7 cells.


Asunto(s)
Peptidomiméticos , Humanos , Relación Estructura-Actividad , Peptidomiméticos/farmacología , Simulación del Acoplamiento Molecular , Lipasa , Obesidad/tratamiento farmacológico , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/química
4.
Org Biomol Chem ; 21(4): 738-742, 2023 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-36601997

RESUMEN

We describe a metal-free strategy to access various α-arylidene cyclopenta[b]indoles via phosphine-catalysed (3 + 2) annulation of α,ß-ynones and 3-nitroindoles. For the first time, the rearomatisation of the indole nucleus was observed in such an annulative transformation. The method was extended to the synthesis of an antimalarial natural product, bruceolline E.

5.
Soft Matter ; 18(45): 8647-8655, 2022 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-36349658

RESUMEN

Jack bean urease, the first nickel metalloenzyme, and crystallized enzymes have historical significance due to their several applications in the biomedical and other fields. For the first time, cross-linker free pH-responsive hydrogel-urease bioconjugates have been reported. Without the use of divinyl benzene or divinyl acrylamide derivatives, urease was immobilized inside the hydrogel matrix and various grades of bioconjugates were synthesized. The hydrogel-urease bioconjugate exhibits excellent swelling-deswelling and pH-responsive characteristics without affecting the urease enzyme. The pH-responsive bioconjugates were characterized by FT-IR, powder XRD, SEM, TGA, and UV-vis spectroscopy. Urea hydrolysis and enzyme affinity have been investigated at pH 4, pH 7, and pH 11 using bioconjugates and free urease. At basic pH, BCs showed excellent enzyme activity. In summary, this technique is effective for stabilizing biomacromolecules at different pHs for a variety of real applications.


Asunto(s)
Urea , Ureasa , Ureasa/química , Urea/química , Hidrólisis , Hidrogeles/química , Acrilamida , Espectroscopía Infrarroja por Transformada de Fourier , Enzimas Inmovilizadas/química , Concentración de Iones de Hidrógeno
6.
Surg Radiol Anat ; 44(1): 83-92, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34994829

RESUMEN

PURPOSE: The physicians say that the least anatomy is required for clinical practice. But the disease causes anatomical distortions or variations in structures impairing functions of organs and systems. So, the diagnosis and analysis of treatment of disease depend on interwoven inter-relationship among Anatomy, Physiology, Pathology, Radiology and clinical sciences. Consequently, the upcoming doctors are to be cultivated sufficient anatomy. Therefore, the objective of this study is to analyze viewpoints of medical students, faculties and practitioners regarding degree of need of Anatomy in clinical practice. METHODS: A feedback survey has been carried out among students and faculties to seek their views on the need of Anatomy in clinical practice using two hypotheses. Hypothesis 1 defines the degree of need of Anatomy ('most essential', 'essential' and 'least essential') in clinical practice based on answers of questionnaire by medical students and faculties, whereas hypothesis 2 assigns weights depending on knowledge and experience of the feedback providers. The means/weighted means of views have been statistically analyzed. Additionally, the literature survey was carried out on the demand, necessity, importance, usefulness and applicability of Anatomy in clinical practice. RESULTS: Our statistical analysis revealed that Anatomy is 'most essential' for clinical practice. In literature survey too, the inadequate knowledge of anatomy among medical students leads to poor comprehension of clinical practice. So, anatomy is most essential for clinical practice. CONCLUSION: Sound knowledge of Human Anatomy is most essential during medical practice for Physicians.


Asunto(s)
Anatomía , Educación de Pregrado en Medicina , Médicos , Radiología , Estudiantes de Medicina , Anatomía/educación , Curriculum , Docentes , Humanos , Encuestas y Cuestionarios
7.
Bull Environ Contam Toxicol ; 108(3): 491-499, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33594450

RESUMEN

The cells of Chlorella vulgaris exhibited NaCl (0-400 mM) induced decrease in the growth, protein, chlorophyll, carbohydrate and total organic carbon, whereas total lipid and proline content increased with rising level of NaCl. Addition of NaHCO3 (20 mM) exhibited antagonistic effect against the adverse effect of salinity on the growth, level of macromolecules except proline. The SEM-EDS analysis of NaCl treated cells exhibited morphological variations as well as reduced accumulation of Na and Cl due to the presence of NaHCO3. The results on chlorophyll fluorescence induction kinetics revealed NaCl induced decline in the photosynthetic performance and quantum yield, while non-photochemical quenching of chlorophyll was enhanced, particularly at lower concentrations of NaCl. Addition of NaHCO3 to NaCl treated cells exhibited further increase in the non-photochemical quenching values. Thus, these results demonstrated that adverse impact of NaCl on the C. vulgaris cells was significantly mitigated in the presence of bicarbonate.


Asunto(s)
Chlorella vulgaris , Microalgas , Bicarbonatos/metabolismo , Bicarbonatos/farmacología , Chlorella vulgaris/metabolismo , Clorofila/metabolismo , Microalgas/metabolismo , Nutrientes , Fotosíntesis , Salinidad
8.
Beilstein J Org Chem ; 18: 1177-1187, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36128432

RESUMEN

Metal-free organic emitters with thermally activated delayed fluorescence (TADF) characteristics are emerging due to the potential applications in optoelectronic devices, time-resolved luminescence imaging, and solid-phase sensing. Herein, we synthesized two (4-bromobenzoyl)pyridine (BPy)-based donor-acceptor (D-A) compounds with varying donor size and strength: the emitter BPy-pTC with tert-butylcarbazole (TC) as the donor and BPy-p3C with bulky tricarbazole (3C) as the donor unit. Both BPy-pTC and BPy-p3C exhibited prominent emission with TADF properties in solution and in the solid phase. The stronger excited-state charge transfer was obtained for BPy-p3C due to the bulkier donor, leading to a more twisted D-A geometry than that of BPy-pTC. Hence, BPy-p3C exhibited aggregation-induced enhanced emission (AIEE) in a THF/water mixture. Interestingly, the singlet-triplet energy gap (ΔE ST) was reduced for both compounds in the aggregated state as compared to toluene solution. Consequently, a faster reverse intersystem crossing rate (k RISC) was obtained in the aggregated state, facilitating photon upconversion, leading to enhanced delayed fluorescence. Further, the lone-pair electrons of the pyridinyl nitrogen atom were found to be sensitive to acidic protons. Hence, the exposure to acid and base vapors using trifluoroacetic acid (TFA) and triethylamine (TEA) led to solid-phase fluorescence switching with fatigue resistance. The current study demonstrates the role of the donor strength and size in tuning ΔE ST in the aggregated state as well as the relevance for fluorescence-based acid-base sensing.

9.
Biomacromolecules ; 22(5): 2211-2223, 2021 05 10.
Artículo en Inglés | MEDLINE | ID: mdl-33905248

RESUMEN

Chemical modification of biopolymers, before use in thermoplastic applications, can reduce the susceptibility to open environment degradation. We demonstrate carbon dots (CDs) as green photocatalytic triggers that can render the common cellulose derivative, cellulose acetate (CA), degradable under open environment relevant conditions. CD-modified cellulose acetate (CA + CD) films were subjected to UV-A irradiation in air and simulated sea water, and the degradation process was mapped by multiple spectroscopic, chromatographic, and microscopy techniques. The addition of CDs effectively catalyzed the deacetylation reaction, the bottleneck preventing biodegradation of CA. The photocatalytically activated degradation process led to significant weight loss, release of small molecules, and regeneration of cellulose fibers. The weight loss of CA + CD after 30 days of UV-A irradiation in air or simulated sea water was 53 and 43%, respectively, while the corresponding values for plain CA films were 12 and 4%. At the same time the weight average molar mass of CA + CD decreased from 62,000 to 11,000 g/mol and 15,000 g/mol during UV-A irradiation in air and simulated sea water, respectively, and the degree of substitution (DS) decreased from 2.2 to 1.6 both in air and in water. The aging in water alone did not affect the weight average molar mass, but the DS was decreased to 1.9. Control experiments confirmed the generation of hydrogen peroxide when aqueous CD dispersion was subjected to UV-A irradiation, indicating a free radical mechanism. These results are promising for the development of products, such as mulching films, with photocatalytically triggered environmental degradation processes.


Asunto(s)
Carbono , Celulosa , Biodegradación Ambiental , Celulosa/análogos & derivados , Peróxido de Hidrógeno
10.
Inorg Chem ; 60(10): 7475-7489, 2021 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-33939401

RESUMEN

The biological enzyme-mimetic activity of cerium oxide nanoparticles (CeNPs) is well known to scavenge the reactive oxygen and nitrogen species in cell culture and animal models, imparting protection from the deleterious effects of oxidative and nitrosative stress. The superoxide dismutase (SOD)- and catalase-mimicking activity of CeNPs is reported to be controlled by the oxidation state of the surface "Ce" ions, where a high ratio of Ce3+/4+ or Ce4+/3+ has been considered for the displayed SOD and catalase-like activity, respectively. However, the redox behavior of CeNPs can be controlled by certain ligands that could offer changes in their enzyme-mimetic properties. Therefore, in this work, we have studied the enzyme-mimetic activities of CeNPs under the influence of polyoxometalates [phosphomolybdic acid (PMA) and phosphotungstic acid (PTA)], which are electron-dense molecules displaying quick and reversible multielectron redox reactions. Results revealed that the interaction of PMA with CeNPs results in the inhibition of the SOD-like activity; however, it has no impact on the catalase-like activity. Contrary to this, the interaction of PTA with CeNPs improved the SOD as well as catalase-like activities of CeNPs (3+), which generally do not exhibit catalase activity in the bare form. Although CeNPs (3+) did not show any peroxidase-like activity, CeNPs (4+) showed excellent activity, which was enhanced after the interaction with polyoxometalates. Further, the autoregeneration ability of CeNPs was found to be intact even after PTA or PMA interaction; however, the full catalytic activity was observed in the case of PTA but partially with PMA.


Asunto(s)
Cerio/metabolismo , Nanopartículas/metabolismo , Superóxido Dismutasa/metabolismo , Compuestos de Tungsteno/metabolismo , Células Cultivadas , Cerio/química , Humanos , Nanopartículas/química , Tamaño de la Partícula , Especies Reactivas de Oxígeno/análisis , Especies Reactivas de Oxígeno/metabolismo , Superóxido Dismutasa/química , Propiedades de Superficie , Compuestos de Tungsteno/química
11.
Natl Med J India ; 33(5): 302-305, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-34213461

RESUMEN

Background: . Availability of donated organs may save lives of people with end-stage disease. However, multiple barriers exist for obtaining donated organs such as insufficient knowledge and lack of a positive attitude towards organ donation. We assessed the knowledge and attitude regarding organ donation among faculty members of a university in India. Methods: . We did this observational, cross-sectional study from December 2017 to January 2018. A structured, close-ended questionnaire consisting of 20 items was used to assess knowledge, attitude and practices regarding organ donation. Data for 170 participants were analysed using SPSS version 21. Unpaired t-test was used to compare the knowledge and attitude score among different variables. Results: . A statistically significant difference was found between the attitude score of graduate and postgraduate faculty (p=0.003), as well as between graduate and doctoral faculty (p=0.001). We found that 5.3% of participants had already donated organs, 12.9% had pledged to donate and 63.5% of participants had expressed willingness to donate organs. Conclusions: . There is a need to increase the knowledge regarding organ donation as most people have a good attitude towards organ donation, but their knowledge was insufficient and at times inaccurate.


Asunto(s)
Obtención de Tejidos y Órganos , Universidades , Estudios Transversales , Docentes , Conocimientos, Actitudes y Práctica en Salud , Humanos , Percepción , Encuestas y Cuestionarios
12.
Mol Cell Biochem ; 454(1-2): 123-138, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30390174

RESUMEN

Natural products from medicinal plants have always attracted a lot of attention due to their diverse and interesting therapeutic properties. We have employed the principles of green chemistry involving isomerization, coupling and condensation reaction to synthesize a class of compounds derived from eugenol, a naturally occurring bioactive phytophenol. The compounds were characterized structurally by 1H-, 13C-NMR, FT-IR spectroscopy and mass spectrometry analysis. The purity of compounds was detected by HPLC. The synthesized compounds exhibited anti-cancer activity. A 10-12-fold enhancement in efficiency of drug molecules (~ 1 µM) was observed when delivered with graphene oxide (GO) as a nanovehicle. Our data suggest cell death via apoptosis in a dose-dependent manner due to increase in calcium levels in specific cancer cell lines. Interestingly, the benzoxazine derivatives of eugenol with GO nanoparticle exhibited enhanced therapeutic potential in cancer cells. In addition to anti-cancer effect, we also observed significant role of these derivatives on parasite suggesting its multi-pharmacological capability.


Asunto(s)
Apoptosis , Benzoxazinas/farmacología , Portadores de Fármacos , Eugenol/farmacología , Grafito , Nanopartículas/química , Neoplasias/tratamiento farmacológico , Antineoplásicos/farmacología , Línea Celular Tumoral , Células HeLa , Humanos , Células MCF-7 , Neoplasias/fisiopatología
13.
AAPS PharmSciTech ; 21(1): 24, 2019 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-31845106

RESUMEN

Conjugation of D-glucosamine with lipophilic moiety can ease its application in surface modification of liposomes. Interestingly, although D-glucosamine is safe, studies have shed light on "toxic effect" of its conjugates on cancer cells and highlighted its application in targeting glioma. However, understanding the safety of such conjugates for local delivery to the brain is unavailable. Herein, after successful synthesis of D-glucosamine conjugate (GC), the toxicity of functionalized liposome was evaluated both in vitro and in vivo. The study revealed a significant effect on cytotoxicity and apoptosis in vitro as assessed on grade IV-resistant glioma cell lines, SF268, U87MG, using MTT assay and PI staining. Additionally, this effect was not observed on normal human erythrocytes in the hemolysis assay. Furthermore, we demonstrated that GC liposomes were non-toxic to the normal brain tissues of healthy Sprague-Dawley rats. Successful functionalization yielded liposome with uniform particle size, stability, and cellular uptake. With < 10% hemolysis, all the liposomal formulations demonstrated hemato-compatibility but led to high glioma cytotoxicity. The surface density of conjugate played an important role in tumor toxicity (0.5 < 1.0 ≤ 2.0% molar ratio). PI staining revealed that compared to control cell, functionalization led 26-fold increase in induction of apoptosis in glioma cells. Absence of histological and behavioral changes along with the absence of caspase-3 in brain tissue confirmed the suitability of the system for direct infusion in the brain. Thus, this study will aid the future development of clinically useful local chemotherapeutic without "add-in" side effects.


Asunto(s)
Encéfalo/metabolismo , Glucosamina/administración & dosificación , Liposomas , Animales , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Sistemas de Liberación de Medicamentos , Glucosamina/química , Humanos , Masculino , Tamaño de la Partícula , Ratas , Ratas Sprague-Dawley
14.
Bioorg Med Chem Lett ; 28(9): 1629-1637, 2018 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-29615339

RESUMEN

Development of new class of anti-malarial drugs is an essential requirement for the elimination of malaria. Bioactive components present in medicinal plants and their chemically modified derivatives could be a way forward towards the discovery of effective anti-malarial drugs. Herein, we describe a new class of compounds, 1,3-benzoxazine derivatives of pharmacologically active phytophenols eugenol (compound 3) and isoeugenol (compound 4) synthesised on the principles of green chemistry, as anti-malarials. Compound 4, showed highest anti-malarial activity with no cytotoxicity towards mammalian cells. Compound 4 induced alterations in the intracellular Na+ levels and mitochondrial depolarisation in intraerythrocytic Plasmodium falciparum leading to cell death. Knowing P-type cation ATPase PfATP4 is a regulator for sodium homeostasis, binding of compound 3, compound 4 and eugenol to PfATP4 was analysed by molecular docking studies. Compounds showed binding to the catalytic pocket of PfATP4, however compound 4 showed stronger binding due to the presence of propylene functionality, which corroborates its higher anti-malarial activity. Furthermore, anti-malarial half maximal effective concentration of compound 4 was reduced to 490 nM from 17.54 µM with nanomaterial graphene oxide. Altogether, this study presents anti-plasmodial potential of benzoxazine derivatives of phytophenols and establishes disruption of parasite sodium homeostasis as their mechanism of action.


Asunto(s)
Antimaláricos/farmacología , Benzoxazinas/farmacología , Homeostasis/efectos de los fármacos , Fenoles/farmacología , Plasmodium falciparum/efectos de los fármacos , Sodio/farmacología , Antimaláricos/síntesis química , Antimaláricos/química , Benzoxazinas/síntesis química , Benzoxazinas/química , Relación Dosis-Respuesta a Droga , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Simulación del Acoplamiento Molecular , Estructura Molecular , Pruebas de Sensibilidad Parasitaria , Fenoles/química , Plasmodium falciparum/crecimiento & desarrollo , Sodio/química , Relación Estructura-Actividad
15.
Indian J Med Res ; 148(1): 25-34, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30264751

RESUMEN

Recourse to litigation and positive judicial interventions is one of the most effective tools to meet public health objectives. The present review envisions compiling litigation and judicial measures in Southeast Asia Region (SEAR) while assessing their role in advancing smokeless tobacco (SLT) control, and equally highlighting, how tobacco industry has used litigation to undermine tobacco control efforts in the Region. The litigation, especially from the SEAR, up to 2017, that have facilitated SLT control or have been used by the tobacco industry to challenge an SLT control policy decision were reviewed. Most of the litigation related to SLT control from the Region are on pictorial health warnings. Bhutan has imposed a complete prohibition on sale, manufacture and import of all kinds of tobacco products and the litigation there relates to the prosecution of offenders for violating the ban. Judiciary in the Region is well informed about the ill-effects of tobacco use and remains positive to tobacco control initiatives in the interest of public health. In India, several SLT-specific litigation helped in better regulation of SLT products in the country. Litigation has compelled governments for effective enforcement of the domestic tobacco control laws and the World Health Organization (WHO) Framework Convention on Tobacco Control (FCTC). Parties to the WHO FCTC must now use Treaty Article 19 to strengthen their legal procedures and make the tobacco industry liable, for both criminal and civil wrongs.


Asunto(s)
Industria del Tabaco , Tabaco sin Humo/legislación & jurisprudencia , Asia Sudoriental , India , Fumar
16.
Appl Opt ; 56(15): 4243-4249, 2017 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-29047845

RESUMEN

This paper reports a comprehensive theoretical study of W-shaped complex type-II InGaAs/InAs/GaAsSb nano-scale heterostructure consisting of two quantum wells of InAs material using the six-band k.p theory. The entire structure has been supposed to be grown on InP substrate. In order to optimize the optical gain, the probability densities of electrons and holes were optimized in the heterostructure. Following these calculations, dispersion relations for electron and hole energies, and transverse electric and transverse magnetic polarizations dependent dipole matrix elements and momentum matrix elements were calculated and, finally, the optical gain in both polarization modes was calculated. For this optimized complex heterostructure, a very high optical gain of the order of ∼4500 cm-1 in the regime of mid-infrared wavelength ∼3.2 µm has been achieved. The results suggest that the designed nano-heterostructure may be utilized for mid-infrared region (MIR) applications such as chemical and bio-molecular sensing of molecules, for the applications of spectroscopy in the "fingerprint region" of molecular science, and for detection of atmospheric gases that respond to 3.2 µm wavelength.

17.
Chemistry ; 21(38): 13210-5, 2015 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-26230355

RESUMEN

A highly efficient synthesis of phenanthridine/benzoxazine-fused quinazolinones by ligand-free palladium-catalyzed intramolecular C-H bond activation under mild conditions has been developed. The C-C coupling provides the corresponding N-fused polycyclic heterocycles in good to excellent yields and with wide functional group tolerance.

18.
Org Biomol Chem ; 13(19): 5475-87, 2015 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-25875403

RESUMEN

DNA ligases are critical components for DNA metabolism in all organisms. NAD(+)-dependent DNA ligases (LigA) found exclusively in bacteria and certain entomopoxviruses are drawing increasing attention as therapeutic targets as they differ in their cofactor requirement from ATP-dependent eukaryotic homologs. Due to the similarities in the cofactor binding sites of the two classes of DNA ligases, it is necessary to find determinants that can distinguish between them for the exploitation of LigA as an anti-bacterial target. In the present endeavour, we have synthesized and evaluated a series of tricyclic dihydrobenzoxazepine and tetracyclic indole derivatives for their ability to distinguish between bacterial and human DNA ligases. The in vivo inhibition assays that employed LigA deficient E. coli GR501 and S. typhimurium LT2 bacterial strains, rescued by ATP-dependent T4 DNA ligase or Mycobacterium tuberculosis NAD(+)-dependent DNA ligase (Mtb LigA), respectively, showed that the compounds can specifically inhibit bacterial LigA. The in vitro enzyme inhibition assays using purified MtbLigA, human DNA ligase I & T4 DNA ligase showed specific inhibition of MtbLigA at low micromolar range. Our results demonstrate that tricyclic dihydrobenzoxazepine and tetracyclic indole derivatives can distinguish between bacterial and human DNA ligases by ∼5-folds. In silico docking and enzyme inhibition assays identified that the compounds bind to the cofactor binding site and compete with the cofactor. Ethidium bromide displacement and gel-shift assays showed that the inhibitors do not exhibit any unwanted general interactions with the substrate DNA. These results set the stage for the detailed exploration of this compound class for development as antibacterials.


Asunto(s)
Bacterias/enzimología , ADN Ligasas/antagonistas & inhibidores , Dibenzoxazepinas/farmacología , Indoles/farmacología , Antibacterianos/farmacología , ADN/metabolismo , ADN Ligasa (ATP) , ADN Ligasas/metabolismo , Dibenzoxazepinas/síntesis química , Dibenzoxazepinas/química , Pruebas de Enzimas , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Escherichia coli/enzimología , Humanos , Indoles/síntesis química , Indoles/química , Pruebas de Sensibilidad Microbiana , Simulación del Acoplamiento Molecular , Mycobacterium tuberculosis/enzimología , Salmonella typhimurium/enzimología
19.
Drug Discov Today ; 29(1): 103855, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38081381

RESUMEN

Obesity is a disease of epidemic proportions, with a worrisome upward trend. The high consumption of lipids, a major energy source, leads to obesity because of their high calorific value. Pancreatic lipase (PTL), produced by pancreatic acinar cells, hydrolyzes 50-70% of triacylglycerol (TAG) from food. PTL-related protein 1 (PLRP1) and 2 (PLRP2) are also produced by these cells. In vertebrates, PLRP1 has relatively less lipolytic activity, whereas PLRP2 has an essential role in lipid digestion, especially in infants. In this review, we summarize the structure and function of PTL, PLRP1, and PLRP2, and the metabolic fate of PTL inhibitors. We also discuss the current status of clinical trials on orlistat and its combinations for obesity treatment.


Asunto(s)
Lipasa , Obesidad , Animales , Humanos , Lipasa/química , Lipasa/metabolismo , Obesidad/tratamiento farmacológico , Obesidad/metabolismo , Orlistat/metabolismo , Páncreas/metabolismo
20.
Environ Sci Pollut Res Int ; 31(25): 36748-36760, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38750276

RESUMEN

Toxic organic dyes (colorants) are one of the main causes of water pollution that releases destructive effluents in the environment. To overcome this issue, a fundamental need to produce a novel, efficient catalyst for the degradation and mineralization of dye mixtures has arisen. The objective of this research is to develop an eminent Ni-doped magnetic carbon aerogel (Ni-MCA) catalyst using graft co-polymerization method having xanthan gum as backbone doped with Ni-magnetic nanoparticles (Ni-MNPs), that do not show agglomeration and easy to separate. The examination revealed that Ni-MCA provided exceptional magnetic characteristics (Ms = 52.75 emu/g) and potent catalytic activity for the degradation of mono- as well as binary-dye solutions of Congo red (CR) and methyl green (MG) dyes. The formation was verified by various characterization techniques such as FTIR, VSM, XRD, XPS, SEM, TEM, and EDX mapping. Interestingly, Ni-MCA shows faster result on anionic dye CR up to 97% with degradation rate of 5.647 × 10-1 min-1, and MG dye shows degradation of 95.7% with the degradation rate of 2.169 × 10-1 min-1, while dye mixture is showing 90% degradation with rate of 2.159 × 10-1 min-1.


Asunto(s)
Carbono , Colorantes , Níquel , Polisacáridos Bacterianos , Contaminantes Químicos del Agua , Níquel/química , Polisacáridos Bacterianos/química , Colorantes/química , Contaminantes Químicos del Agua/química , Carbono/química , Catálisis , Geles/química
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