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1.
Cureus ; 16(4): e58495, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38765404

RESUMEN

INTRODUCTION: Identification is an important aspect of forensic medicine. Identification plays an imperative role, especially in highly decomposed bodies, mutilated bodies, and undisclosed and fragmentary human remains. The estimation of sex is an essential parameter of human identification. In forensic anthropometry, sex determination is related to morphometric characteristics of skeletal bones, such as the skull and mandible, clavicle, sternum, scapula, humerus, pelvic bone, sternum, and femur. Since teeth are decay-resistant, conscientious analysis of teeth can accredit reliable sex estimation of an individual, especially when other determinants are fragmented or destroyed. AIM: The aim of the study was to explore the association between sex and buccolingual crown dimensions of teeth. MATERIALS AND METHODS: The study sample consists of 100 volunteer subjects (50 male subjects and 50 female subjects) aged between 20 and 35 years. Alginate was used to take impressions of the teeth and the cast was prepared using pouring by dental stone. Measurements of buccolingual parameters of all the teeth (except the third molars) of both jaws were done on dental casts by using a digital caliper. RESULTS: Collected data were analyzed using SPSS software (IBM Corp., Armonk, NY) and were outlined as mean and standard deviation (SD). The male and female groups were compared using an independent Student's t-test or unpaired test. The results of this study revealed that 16 out of 28 odontometric parameters (except third molar) of the two groups (male and female) were higher in the male group as compared to the female group (p < 0.05). CONCLUSION: Buccolingual odontometric parameters can be used for sex estimation in the North Indian population.

2.
Plants (Basel) ; 12(17)2023 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-37687372

RESUMEN

The agricultural practices of breeding, farm management and cultivation have improved production, to a great extent, in order to meet the food demands of a growing population. However, the newer challenges of climate change, global warming, and nutritional quality improvement will have to be addressed under a new scenario. Plant biotechnology has emerged as a reliable tool for enhancing crop yields by protecting plants against insect pests and metabolic engineering through the addition of new genes and, to some extent, nutritional quality improvement. Plant tissue culture techniques have provided ways for the accelerated clonal multiplication of selected varieties with the enhanced production of value-added plant products to increase modern agriculture. The in vitro propagation method has appeared as a pre-eminent approach for the escalated production of healthy plants in relatively shorter durations, also circumventing seasonal effects. However, there are various kinds of factors that directly or indirectly affect the efficiency of in vitro regeneration like the concentration and combination of growth regulators, variety/genotype of the mother plant, explant type, age of seedlings and other nutritional factors, and elicitors. Nanotechnology as one of the latest and most advanced approaches in the material sciences, and can be considered to be very promising for the improvement of crop production. Nanomaterials have various kinds of properties because of their small size, such as an enhanced contact surface area, increased reactivity, stability, chemical composition, etc., which can be employed in plant sciences to alter the potential and performance of plants to improve tissue culture practices. Implementing nanomaterials with in vitro production procedures has been demonstrated to increase the shoot multiplication potential, stress adaptation and yield of plant-based products. However, nanotoxicity and biosafety issues are limitations, but there is evidence that implies the promotion and further exploration of nanoparticles in agriculture production. The incorporation of properly designed nanoparticles with tissue culture programs in a controlled manner can be assumed as a new pathway for sustainable agriculture development. The present review enlists different studies in which treatment with various nanoparticles influenced the growth and biochemical responses of seed germination, as well as the in vitro morphogenesis of many crop species. In addition, many studies suggest that nanoparticles can be useful as elicitors for elevating levels of important secondary metabolites in in vitro cultures. Recent advancements in this field also depict the suitability of nanoparticles as a promising carrier for gene transfer, which show better efficiency than traditional Agrobacterium-mediated delivery. This review comprehensively highlights different in vitro studies that will aid in identifying research gaps and provide future directions for unexplored areas of research in important crop species.

3.
Bioresour Technol ; 387: 129659, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37573982

RESUMEN

In order to combat the environmental issues associated with the burning of spent aromatic biomass (SAB), a method for alkaline hydrolysis of SAB has been developed to afford phenolic acids, predominantly the p-coumaric acid, lignin, and cellulose. Lignin (∼15 wt%) from alkaline hydrolysate was separated by precipitation while a mixture of phenolic acids obtained was directly reacted with a green reagent, PhI(OAc)2, under one-pot condition to afford a mixture of p-hydroxybenzaldehyde (>90 wt%) and vanillin (<10 wt%). Unreacted biomass obtained in the process was successfully used as a substrate for the production of cellulose (∼40 wt%). The developed method exhibits potential for application on an industrial scale.


Asunto(s)
Celulosa , Lignina , Aldehídos , Biomasa , Hidrólisis , Fenoles
4.
Cureus ; 15(12): e51106, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38274921

RESUMEN

Background In the field of medical education, traditional methods of teaching and learning have been used for a long time. Various new methods of learning, like activity-based learning (ABL), case-based discussion (CBD), and problem-based learning (PBL), are laying the foundation for this modern era of teaching. This study was a comparative study conducted to determine the effectiveness of activity-based learning and traditional lectures by teaching two topics to MBBS first-year professional students. Aims The study compares the effectiveness of didactic lectures and activity-based learning for MBBS first-year professional students in the subject of anatomy.  Methodology The study was conducted in the Department of Anatomy Hind Institute of Medical Sciences, Barabanki, and included 100 MBBS (2022-2023) first-year students randomly assigned to Group A (n=50, 16 females and 34 males) and Group B (n=50, 23 females and 27 males) through chit methods. The participants were exposed to two different topics of anatomy in the form of activity-based learning as well as didactic lectures. Assessments were done immediately after the exposure in the form of a post-test, and results were analyzed for both groups. Result The results of the study showed that both activity-based learning and didactic lectures were effective in teaching the two topics, but the didactic lecture group had higher retention rates than the activity-based learning group. The mean score of post-tests of students who attended a didactic lecture on the brachial plexus (6.166± 2.11) was slightly higher than that obtained by students who attended activity-based learning (5.625 ± 2.12), but the p-value obtained was not significant (0.249). Whereas the mean of the scores of the post-test obtained by students who attended a didactic lecture on mammary gland was (8.45± 1.20), slightly lower than the mean of the scores of the post-test of students who attended activity-based learning on mammary gland (8.60± 1.16), but the p-value obtained was not significant (0.520). Conclusion This study provides evidence that didactic lectures play an important role in teaching anatomy to MBBS first-year students and cannot be replaced by activity-based learning alone. Lectures followed by activity-based learning can prove to be a newer and more effective teaching-learning method with better outcomes in the form of retention and conceptual understanding of the topics in anatomy.

5.
ACS Chem Neurosci ; 13(23): 3271-3280, 2022 12 07.
Artículo en Inglés | MEDLINE | ID: mdl-36414325

RESUMEN

A new andrographolide-based terminal alkyne 3 was synthesized in good yield from deoxy-andrographolide 2, obtained from a natural compound andrographolide 1, which in turn was isolated from the leaves of the plant Andrographis paniculata. Copper(I)-catalyzed azide-alkyne cycloaddition reaction of alkyne 3 with azido-sugars 4a-f furnished a library of andrographolide-fastened triazolyl glycoconjugates 5a-f in good yields. The structures of these semisynthetic andrographolide derivatives were established by Fourier transform infrared, NMR, and mass spectroscopy. The compounds 5a-f were further evaluated against Alzheimer's disease (AD) using a scopolamine (SCOP)-induced memory impairment mice model. It was observed that antioxidant and anticholinesterase properties of these compounds contribute significantly toward their remarkable potential to improve cognitive functioning.


Asunto(s)
Enfermedad de Alzheimer , Animales , Ratones , Enfermedad de Alzheimer/tratamiento farmacológico
6.
ACS Omega ; 7(42): 37112-37121, 2022 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-36312433

RESUMEN

Novel hydroxyanthracene-based terminal alkynes 3 and 5a/b were synthesized by the acetylide addition reaction at the 9,10-position of anthraquinone 1 under mild conditions. The developed alkynes 3, 5a, and 5b on Huisgen azide-alkyne cycloaddition reaction with azido-sugars 6 in the presence of Cu(I) catalyst provided a series of triazole fasten hydroxyanthracene glycoconjugates 7, 8, and 9, respectively, in good yields. The representative compounds 9 and 7h were successfully deprotected under room-temperature conditions to liberate the corresponding free glycoconjugates 10 and 11, respectively. Further, structures of a few compounds were unmaliciously evidenced by their single-crystal X-ray.

7.
Nat Prod Res ; 36(21): 5438-5448, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34905436

RESUMEN

The naturally occurring compound andrographolide 1 was used as a substrate for the synthesis of a novel terminal alkyne 3 which on copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC) reaction with azides 4a-l, 7 and 9 furnished a series of regioselective andrographolide triazolyl conjugates 5a-l, 8 and 10, respectively. A free glycoconjugate 6 was also prepared by selective deprotection of compound 5i in good yield. All the compounds were characterized by absorbance, FT-IR, NMR, and HR-MS analyses. The triazolyl conjugate 8 was further investigated as a probe for selective detection of Fe3+ ion in matrix. The mode of attachment of Fe3+ ion to the compound 8 was established by absorbance, fluorescence, infrared (IR), and nuclear magnetic resonance (NMR) spectroscopy, and high resolution mass-spectrometry (HR-MS). The logic gate circuits were constructed for the probe 8 and ethylenediaminetetraacetic acid (EDTA). The environmental perspective of probe 8 was investigated in real water samples.


Asunto(s)
Azidas , Química Clic , Espectroscopía Infrarroja por Transformada de Fourier , Azidas/química , Alquinos/química , Cobre/química , Hierro , Iones , Catálisis
8.
Langmuir ; 35(49): 16335-16340, 2019 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-31715104

RESUMEN

Here, we report a method for facile gram-scale synthesis of tetrahedrite (Cu12Sb4S13) nanoparticles (NPs) with high quality and good reproducibility. The obtained NPs had a well-defined tetrahedral shape with a mean edge length of ∼70 nm. We sintered the NPs by the hot press technique to fabricate a nanostructured pellet for thermoelectric measurements. The figure of merit (ZT) value of the pellet was 0.52 at 675 K, which was comparable with the ZT value of the non-nanostructured counterpart.

9.
ACS Omega ; 4(15): 16402-16408, 2019 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-31616818

RESUMEN

Direct energy conversion of heat into electricity using thermoelectric materials is an attractive solution to help address global energy issues. Developing novel materials composed of earth-abundant and nontoxic elements will aid progress toward the goal of sustainable thermoelectric materials. In this study, we chemically synthesized Cu-Zn-Sn-S nanocrystals and fabricated a Cu3ZnSnS5-y thermoelectric material using nanocrystals as building blocks. The figure-of-merit (ZT) value of the Cu3ZnSnS5-y material was found to be 0.39 at 658 K. We substituted Zn with Al in the Cu3ZnSnS5-y system to form Cu3Zn1-x Al x SnS5-y (x = 0.25, 0.5, 0.75, and 1) to lower the lattice thermal conductivity of the resulting materials. Complete substitution of Al for Zn substantially decreased the lattice thermal conductivity and dramatically increased the electrical conductivity of the material. However, the ZT value could not be significantly enhanced, which could be primarily attributed to the high carrier thermal conductivity. These results highlight the production of Cu3Zn1-x Al x SnS5-y thermoelectric materials and unveil the scope for improvement of ZT values by altering transport properties.

10.
Bioresour Technol ; 293: 122105, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31514116

RESUMEN

This work aimed to develop a green protocol for chemical processing of spent aromatic biomass to obtain xylose, levulinic acid, and lignin in good yields via treatment with p-cymene-2-sulphonic acid (p-CSA), a Brønsted acid synthesised from d-limonene as a renewable feedstock from citrus waste. Chemical processing of palmarosa biomass with p-CSA under heating in an autoclave resulted in hydrolysate containing xylose (~16% yield). Further processing of pre-treated biomass with p-CSA in presence of aq. HCl under refluxing caused a selective degradation of cellulose to levulinic acid (~22% yield with respect to biomass). The residual biomass was used to afford lignin in good yields.


Asunto(s)
Citrus , Lignina , Biomasa , Ácidos Levulínicos , Limoneno , Xilosa
11.
Nat Prod Res ; 33(15): 2236-2242, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30067085

RESUMEN

Aegle marmelos is a plant species native to India. Commercially available food products such as jam, jelly, candy, squash etc. are prepared from ripe fruit pulp of A. marmelos. Ripe fruit processing accounts for 60% of whole fruit mass while 40% remains unutilized and generates waste (hard shell, pomace, fiber and seeds) on a massive scale which do not have high value applications. A new flavone 3,5,7-trihydroxy-2-(4'-hydroxy-3'-isopentyloxyphenyl-4H-chromen-4-one (5) in addition to the known compounds 1-4, has been isolated from seeds of A. marmelos. Also, compound 7-(3'-methylbut-2'-enyloxy)-2H-chromen-2-one (2) has been isolated for the first time from A. marmelos. The structure of compounds 1-5 was determined by spectral analysis (UV, IR, NMR, etc.). Additionally, the non-edible oil obtained from seeds was investigated for waste to wealth recovery of 6-O-ascorbyl esters in high regioselectivity via one step semi-synthetic approach in the presence of ascorbic acid and H2SO4 at ambient temperature.


Asunto(s)
Aegle/química , Benzopiranos/aislamiento & purificación , Flavonoides/aislamiento & purificación , Benzopiranos/química , Ésteres/aislamiento & purificación , Flavonoides/química , Extractos Vegetales/análisis , Semillas/química
12.
Bioresour Technol ; 250: 621-624, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29220805

RESUMEN

In citrus processing industries, where up to 60% of the whole fruit is discarded, generates citrus waste (peel, seeds, membrane, and pulp) on a massive scale. The waste does not currently have high-value applications, instead the majority is disposed of or pelletized for animal feed. Therefore, a concise and efficacious protocol for processing of Kinnow mandarin (Citrus reticulata) fruit waste to numerous novel Brønsted acidic ionic liquids (3a-k) have been developed. BAILs were characterized using spectroscopic techniques (FT-IR and NMR). Water immiscibility of ILs 3a, 3g and 3h, a property never observed with sulfonic acid ILs, allowed the catalytic application of BAIL 3a in hydrolysis of sucrose/table sugar, giving a mixture of d-glucose and d-fructose in excellent yields. The ionic liquid could be recycled for >3 times without significant loss of activity.


Asunto(s)
Citrus , Sacarosa , Animales , Frutas , Hidrólisis , Líquidos Iónicos , Espectroscopía Infrarroja por Transformada de Fourier
13.
Glycoconj J ; 34(1): 61-70, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27699585

RESUMEN

The 1,3-dipolar cycloaddition of deoxy-azido sugars 1 with alkyne derivatives of p-vanillin, 3-methoxy-4-(prop-2-ynyloxy)benzaldehyde (2) and 2-methoxy-1-(prop-2-ynyloxy)-4-((prop-2-ynyloxy)methyl)benzene) (4) to afford regioselective triazole-linked vanillinglycoconjugates 5 and 6 was investigated in the presence of CuI/DIPEA in dichloromethane. All the developed glycoconjugates were characterized on the basis of IR, NMR, and MS. Graphical abstract Triazolyl vanillin glycoconjugates via click chemistry.


Asunto(s)
Benzaldehídos/química , Química Clic/métodos , Glicoconjugados/síntesis química , Glicósidos/química , Triazoles/química , Glicoconjugados/química
14.
Glycoconj J ; 32(3-4): 127-40, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25869315

RESUMEN

The 1,3-dipolar cycloaddition of deoxy-azido sugars 1 with O-benzylquercetin alkynes (5-7) to afford regioselective triazole-linked O-benzylquercetin glycoconjugates (8-10) was investigated in the presence of CuI/DIPEA in dichloromethane. All the developed glycoconjugates (8-10) were evaluated for anti-leishmanial activity against the promastigotes and amastigotes of Leishmania donovani. Graphical Abstract Click Inspired Synthesis of Antileishmanial Triazolyl O-Benzylquercetin Glycoconjugates.


Asunto(s)
Química Clic , Quercetina/química , Tripanocidas/síntesis química , Tripanocidas/farmacología , Animales , Línea Celular/efectos de los fármacos , Evaluación Preclínica de Medicamentos/métodos , Leishmania donovani/efectos de los fármacos , Macrófagos/efectos de los fármacos , Ratones , Triazoles/síntesis química , Tripanocidas/química
15.
Talanta ; 80(2): 532-8, 2009 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-19836516

RESUMEN

An efficient colorimetric chemosensor with a thiourea binding site and 2-amino-6-nitrobenothiazole as a signaling unit has been synthesized by dithiocarbamate approach. The chemosensor has been utilized for selective recognition of fluoride and acetate anions in dry DMSO solution by UV-vis and (1)H NMR titration experiments. The chemosensor has shown naked-eye sensitivity for both the anions in solution.


Asunto(s)
Acetatos/análisis , Técnicas Biosensibles/métodos , Colorimetría/métodos , Fluoruros/análisis , Tiourea/química , Acetatos/química , Aniones/análisis , Aniones/química , Dimetilsulfóxido/química , Fluoruros/química , Espectroscopía de Resonancia Magnética , Modelos Químicos , Estructura Molecular , Reproducibilidad de los Resultados , Espectrofotometría , Tiazoles/química
16.
Bioorg Khim ; 35(1): 70-5, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19377524

RESUMEN

Modified fluorescent probe U(F)AA AAT CTC CGC CGC has been synthesized using the nucleoside analogue 3'-O-(N,N'-diisopropylamino-2-cyanoethoxyphosphinyl)-5'-O-(4,4'-dimethoxytrityl)-2'-O-(dansyl-1-sulfonamidohexylaminocarbonyl)uridine for hybridization studies with perfectly matched (U/A) complementary and with DNA strand having similar G-rich telomeric units at the 3'-end. The thermal stability data and decrease in fluorescence intensity due to the presence of dG units clearly demonstrated the potential application of this approach in DNA diagnostics in homogeneous hybridization assays.


Asunto(s)
Sondas de ADN/química , Desoxiguanosina/química , Colorantes Fluorescentes/química , Hibridación de Ácido Nucleico
17.
Bioorg Med Chem Lett ; 18(19): 5217-21, 2008 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-18783945

RESUMEN

An efficient heterobifunctional reagent, N-(3-triethoxysilylpropyl)-4-(isothiocyanatomethyl)cyclohexane-1-carboxamide (TPICC) has been developed by a simple 'two step reaction' for the preparation of bioconjugates and immobilization of biomolecules such as oligonucleotides, peptides and proteins on the glass surface. The isothiocyanate functionality at one end of the reagent, TPICC was found specific for the ligands having either aminoalkyl (RNH(2)) or mercaptoalkyl (R-SH) functionality. The synthesis of bioconjugates with the reagent was achieved through its isothiocyanate functionality at one end via the formation of stable thiourea linkage with aminoalkyl and dithiocarbamate linkage with mercaptoalkyl derivatives. The triethoxysilyl functionality of the reagent has been utilized for specific coupling with the virgin glass surface by a very simple methodology.


Asunto(s)
Ciclohexanos/síntesis química , Isotiocianatos/síntesis química , Secuencia de Aminoácidos , Secuencia de Bases , Reactivos de Enlaces Cruzados , Ciclohexanos/química , Ciclohexanos/farmacología , Fluorescencia , Vidrio/química , Indicadores y Reactivos , Isotiocianatos/química , Isotiocianatos/farmacología , Estructura Molecular , Sondas de Oligonucleótidos/química , Tiourea/química
18.
Nucleic Acids Symp Ser (Oxf) ; (51): 329-30, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-18029720

RESUMEN

An efficient heterobifunctional reagent, N-(3-triethoxysilylpropyl)-4-(N'-maleimidylmethyl) cyclohexanamide (TPMC) was developed for the immobilization of thiol-modified oligonucleotide on the unmodified glass surface. The heterobifuntionality of the reagent was utilized for construction of DNA microarray in which the triethoxysilyl functionality has specificity towards the glass surface while the maleimide functionality for thiol-modified oligonucleotides via stable thio-ether linkage. Immobilization of DNA has been achieved by two alternative approaches. The applicability of the reagent was explored by hybridization studies with the fluorescein labeled complementary DNA strand.


Asunto(s)
Ciclohexanos/química , Maleimidas/química , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , Tionucleótidos/química , Vidrio/química , Indicadores y Reactivos , Compuestos de Sulfhidrilo/química
19.
Anal Biochem ; 369(2): 248-55, 2007 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-17606218

RESUMEN

An efficient heterobifunctional reagent, N-(3-triethoxysilylpropyl)-4-(N'-maleimidylmethyl) cyclohexanamide (TPMC), was developed for the immobilization of thiol-modified oligonucleotides on an unmodified glass surface. The heterobifunctionality of the reagent was used for the construction of a DNA microarray in which the triethoxysilyl functionality has specificity toward a glass surface, whereas the maleimide functionality has thiol-modified oligonucleotides via a stable thioether linkage. Immobilization of DNA was achieved by two alternative approaches. In the first approach, the reagent TPMC was treated with oligonucleotides to get triethoxysilyl-oligonucleotide conjugate, which was then covalently attached via specific triethoxysilyl functionality to an unmodified glass surface. In the second approach, the reagent was first covalently linked with an unmodified glass surface to get maleimide functionality on a glass surface, which was then used for the immobilization of oligonucleotides via a stable thioether linkage. The applicability of the reagent was explored by hybridization studies with the fluorescein-labeled complementary DNA strand and in mismatch discrimination.


Asunto(s)
Ciclohexanos/síntesis química , Vidrio/química , Maleimidas/química , Maleimidas/síntesis química , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , Oligonucleótidos/química , Compuestos de Sulfhidrilo/química , Disparidad de Par Base , Secuencia de Bases , ADN Complementario/química , Fluoresceína/química , Hibridación de Ácido Nucleico , Análisis de Secuencia por Matrices de Oligonucleótidos/instrumentación , Sensibilidad y Especificidad , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción
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