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1.
Nano Lett ; 24(17): 5342-5350, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38630899

RESUMO

CuInS2 (CIS) quantum dots (QDs) represent an important class of colloidal materials with broad application potential, owing to their low toxicity and unique optical properties. Although coating with a ZnS shell has been identified as a crucial method to enhance optical performance, the occurrence of cation exchange has historically resulted in the unintended formation of Cu-In-Zn-S alloyed QDs, causing detrimental blueshifts in both absorption and photoluminescence (PL) spectral profiles. In this study, we present a facile one-pot synthetic strategy aimed at impeding the cation exchange process and promoting ZnS shell growth on CIS core QDs. The suppression of both electron-phonon interaction and Auger recombination by the rigid ZnS shell results in CIS/ZnS core/shell QDs that exhibit a wide near-infrared (NIR) emission coverage and a remarkable PL quantum yield of 92.1%. This effect boosts the fabrication of high-performance, QD-based NIR light-emitting diodes with the best stability of such materials so far.

2.
Chemistry ; 30(33): e202400675, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38587031

RESUMO

Alkylation reactions are pivotal in organic chemistry, with wide-ranging utilization across various fields of applied synthetic chemistry. However, conventional reagents employed in alkylations often pose substantial health and exposure risks. Quaternary ammonium salts (QAS) present a promising alternative for these transformations offering significantly reduced hazards as they are non-cancerogenic, non-mutagenic, non-flammable, and non-corrosive. Despite their potential, their use in direct organic transformations remains relatively unexplored. This review outlines strategies for utilizing QAS as alternative reagents in alkylation reactions, providing researchers with safer approaches to chemical synthesis.

3.
Environ Sci Technol ; 58(27): 12155-12166, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38934735

RESUMO

The rising in situ chemical oxidation (ISCO) technologies based on polymerization reactions have advanced the removal of emerging contaminants in the aquatic environment. However, despite their promise, uncertainties persist regarding their effectiveness in eliminating structurally complex contaminants, such as sulfonamide antibiotics (SAs). This study elucidated that oligomerization, rather than mineralization, predominantly governs the removal of SAs in the carbon materials/periodate system. The amine groups in SAs played a crucial role in forming organic radicals and subsequent coupling reactions due to their high f- index and low bond orders. Moreover, the study highlighted the robust adhesion of oligomers to the catalyst surface, facilitated by enhanced van der Waals forces and hydrophobic interactions. Importantly, plant and animal toxicity assessments confirmed the nontoxic nature of oligomers deposited on the carbon material surface, affirming the efficacy of carbon material-based ISCO in treating contaminated surface water and groundwater. Additionally, a novel classification approach, Δlog k, was proposed to differentiate SAs based on their kinetic control steps, providing deeper insights into the quantitative structure-activity relationship (QSAR) and facilitating the selection of optimal descriptors during the oligomerization processes. Overall, these insights significantly enhance our understanding of SAs removal via oligomerization and demonstrate the superiority of C-ISCO based on polymerization in water decontamination.


Assuntos
Antibacterianos , Carbono , Sulfonamidas , Antibacterianos/química , Carbono/química , Sulfonamidas/química , Poluentes Químicos da Água/química , Purificação da Água
4.
Bioorg Chem ; 151: 107669, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39067421

RESUMO

Parkinson's disease (PD) is the second most prevalent neurodegenerative disorder worldwide, and the therapeutic is focused on several approaches including the inhibition of fibril formation by small compounds, avoiding the formation of cytotoxic oligomers. Thus, we decided to explore the capacity of compounds carrying catechol moieties to inhibit the progression of α-synuclein. Overall, the compounds rosmarinic acid (1), carnosic acid (2), carnosol (3), epiisorosmanol (4), and rosmanol (5) avoid the progression of fibril formation assessed by Thiofavine T (ThT), and atomic force microscopy images showed that morphology is influenced for the actions of compounds over fibrillization. Moreover, ITC experiments showed a Kd varying from 28 to 51 µM, the ΔG showed that the reaction between compounds and α-syn is spontaneous, and ΔH is associated with an exothermic reaction, suggesting the interactions of hydrogen bonds among compounds and α-syn. Docking experiments reinforce this idea showing the intermolecular interactions are mostly hydrogen bonding within the sites 2, 9, and 3/13 of α-synuclein, and compounds 1 and 5. Thus, compound 1, rosmarinic acid, interestingly interacts better with site 9 through catechol and Lysines. In cultured Raw 264. 7 cells, the presence of compounds showed that most of them can promote cell differentiation, especially rosmarinic acid, and rosmanol, both preserving tubulin cytoskeleton. However, once we evaluated whether or not the aggregates pre-treated with compounds could prevent the disruption of microtubules of Raw 264.7 cells, only pre-treated aggregates with rosmarinic acid prevented the disruption of the cytoskeleton. Altogether, we showed that especially rosmarinic acid not only inhibits α-syn but stabilizes the remaining aggregates turning them into not-toxic to Raw 264.7 cells suggesting a main role in cell survival and antigen processing in response to external α-syn aggregates.

5.
Biofouling ; 40(1): 76-87, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38384189

RESUMO

The use of ultraviolet-C (UV-C) irradiation in marine biofouling control is a relatively new and potentially disruptive technology. This study examined effects of UV-C exposure on the biofilm-forming diatom, Navicula incerta. UV-C-induced mutations were identified via Illumina HiSeq. A de novo genome was assembled from control sequences and reads from UV-C-exposed treatments were mapped to this genome, with a quantitative estimate of mutagenesis then derived from the frequency of single nucleotide polymorphisms. UV-C exposure increased cyclobutane pyrimidine dimer (CPD) abundance with a direct correlation between lesion formation and fluency. Cellular repair mechanisms gradually reduced CPDs over time, with the highest UV-C fluence treatments having the fastest repair rates. Mutation abundances were, however, negatively correlated with CPD abundance suggesting that UV-C exposure may influence lesion repair. The threshold fluence for CPD formation exceeding CPD repair was >1.27 J cm-2. Fluences >2.54 J cm-2 were predicted to inhibit repair mechanisms. While UV-C holds considerable promise for marine antifouling, diatoms are just one, albeit an important, component of marine biofouling communities. Determining fluence thresholds for other representative taxa, highlighting the most resistant, would allow UV-C treatments to be specifically tuned to target biofouling organisms, whilst limiting environmental effects and the power requirement.


Assuntos
Diatomáceas , Dímeros de Pirimidina , Diatomáceas/genética , Biofilmes , Reparo do DNA , Mutagênese , Raios Ultravioleta
6.
Curr Issues Mol Biol ; 45(9): 7087-7096, 2023 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-37754232

RESUMO

Non-small cell lung cancer (NSCLC) continues to be the leading cause of cancer-related deaths. Although advances have been made in the past decade to treat such tumors, most options induce multiple side effects, and many patients discontinue therapy due to toxicity. Thus, the need remains for non-toxic, effective NSCLC therapies, especially in an elderly patient population. Our lab has previously identified a protein fraction from the nutraceutical Avemar®-dubbed fermented wheat germ protein (FWGP)-with demonstrated efficacy in lymphoma models both in vitro and in vivo. Here, we show that FWGP also has anti-tumor activity in vitro and in vivo against lung cancer. In vitro cytotoxicity against multiple lung cancer cell lines yielded IC50 values comparable to those previously established with the parent product, Avemar. Further, significant A549 xenograft growth inhibition occurred in athymic nu/nu mice receiving FWGP in both pre-radiated and non-radiated models when compared to the untreated control. Encouragingly, mice treated with FWGP experienced no toxicities as detected by weight reduction or blood chemistry analysis. These data support the further study of FWGP as a potential non-toxic therapy for lung cancer and other oncologic indications.

7.
Eur J Nucl Med Mol Imaging ; 50(11): 3324-3348, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37395802

RESUMO

This document provides the new EANM guideline on radioiodine therapy of benign thyroid disease. Its aim is to guide nuclear medicine physicians, endocrinologists, and practitioners in the selection of patients for radioiodine therapy. Its recommendations on patients' preparation, empiric and dosimetric therapeutic approaches, applied radioiodine activity, radiation protection requirements, and patients follow-up after administration of radioiodine therapy are extensively discussed.


Assuntos
Doença de Graves , Proteção Radiológica , Doenças da Glândula Tireoide , Humanos , Radioisótopos do Iodo/uso terapêutico , Doença de Graves/tratamento farmacológico , Doenças da Glândula Tireoide/radioterapia , Doenças da Glândula Tireoide/tratamento farmacológico , Radiometria
8.
Chemistry ; 29(10): e202202887, 2023 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-36399427

RESUMO

Artificial channels capable of facilitating the transport of Cl- ions across cell membranes while being nontoxic to the cells are rare. Such synthetic ion channels can mimic the functions of membrane transport proteins and, therefore, have the potential to treat channelopathies by replacing defective ion channels. Here we report isophthalic acid-based structurally simple molecules 1 a and 2 a, which self-assemble to render supramolecular nanochannels that allow selective transport of Cl- ions. As evident from the single-crystal X-ray diffraction analysis, the self-assembly is governed by intermolecular hydrogen bonding and π-π stacking interactions. The MD simulation studies for both 1 a and 2 a confirmed the formation of stable Cl- channel assembly in the lipid membrane and Cl- transport through them. The MQAE assay showed the efficacy of the compounds in delivering Cl- ions into cells, and the MTT assays proved that the compounds are nontoxic to cells even at a concentration of 100 µM.


Assuntos
Canais de Cloreto , Ácidos Ftálicos , Canais Iônicos/química , Células Epiteliais
9.
Pharm Res ; 40(10): 2281-2290, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37016170

RESUMO

BACKGROUND: Ovarian cancer is the most lethal cancer in gynaecology. Surgery, chemotherapy, and radiotherapy are the most often used cancer-fighting strategies. Post-surgery infection is fairly prevalent, especially among people with insufficient immunity. Zinc oxide nanoparticles (ZnOnps) have amazing biomedical features as anticancer and antibacterial agents. METHODS: We investigated the behaviour of ZnOnps synthesized by green methods on ovarian cancers using established human ovarian cancer cell lines, besides the antibacterial action toward models of gram + ve and gram -ve bacteria. The cytotoxic effect of ZnOnps was calculated using a Sulforhodamine B (SRB) trial. Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) were tested as models for gram + ve and gram -ve bacteria. The selected bacteria were subjected to concentrations of 20, 40, 80, and 100 µg/ml. RESULTS: The synthesized ZnOnps induced 50% inhibitory concentration (IC50) at a concentration of 27.45 µg/ml. The diameter of inhibition ranged between 20.16 ± 0.16 and 27 ± 0.57 mm for S. aureus and 25.66 ± 0.33 to 31 ± 0.33 mm for E. coli. ZnOnps antagonistic effect statistically differed with neomycin, cefaclor, and cefadroxil. CONCLUSIONS: Green synthesis of ZnOnps is easily prepared, low cost, non-toxic, and eco-friendly. Their cytotoxic action on SKOV3 cells and their antibacterial characteristics pave the way to be an alternative therapy for ovarian cancer and S. aureus and E. coli infection.


Assuntos
Antineoplásicos , Nanopartículas Metálicas , Nanopartículas , Neoplasias Ovarianas , Óxido de Zinco , Humanos , Feminino , Staphylococcus aureus , Óxido de Zinco/farmacologia , Escherichia coli , Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Neoplasias Ovarianas/tratamento farmacológico
10.
Langenbecks Arch Surg ; 408(1): 200, 2023 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-37204607

RESUMO

BACKGROUND: We have performed an updated meta-analysis of randomized controlled trials (RCT) comparing total thyroidectomy (TT) with less than total thyroidectomy (LTT) for benign multinodular non-toxic goiter (BMNG). OBJECTIVES: The objective was to evaluate the effects and outcomes of TT as compared to LTT. METHODS: Eligibility criteria: RCTs comparing TT vs LTT. INFORMATION SOURCES: PubMed, Embase, Cochrane Library and online registers were searched for articles comparing TT with LTT. Risk of bias: Articles were assessed for risk of bias using the Cochrane's revised tool to assess risk of bias in randomized trials (RoB 2 tool). SYNTHESIS OF RESULTS: The main summary measures were risk difference using a random effects model. RESULTS: Five randomized controlled trials were included in the meta-analysis. Recurrence rate was lower for TT compared to LTT. Adverse events like temporary or permanent recurrent laryngeal nerve (RLN) palsy and permanent hypoparathyroidism were similar in both groups except for the rate of temporary hypoparathyroidism which was lower in the LTT group. DISCUSSION: All studies had unclear risk of bias for blinding of the participants and personnel and high risk of bias for certain selective reporting. This meta-analysis did not show any clear benefit or harm of either procedure (TT vs LTT) for goiter recurrence and re-operation rates (for both recurrence and incidental thyroid cancer). However, re-operation for goiter recurrence was significantly higher in the LTT group based on a single RCT. Evidence suggests increased rates of temporary hypoparathyroidism with TT but there was no difference in the rate of RLN palsy and permanent hypoparathyroidism between the two methods. The overall quality of evidence was low to moderate.


Assuntos
Bócio Nodular , Hipoparatireoidismo , Paralisia das Pregas Vocais , Humanos , Bócio Nodular/cirurgia , Bócio Nodular/etiologia , Tireoidectomia/efeitos adversos , Tireoidectomia/métodos , Recidiva Local de Neoplasia/cirurgia , Hipoparatireoidismo/etiologia , Paralisia das Pregas Vocais/etiologia
11.
Biofouling ; 39(8): 775-784, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37822262

RESUMO

In the current study we investigate the antifouling potential of three polyphenolic resveratrol multimers (-)-hopeaphenol, vaticanol B and vatalbinoside A, isolated from two species of Anisoptera found in the Papua New Guinean rainforest. The compounds were evaluated against the growth and settlement of eight marine microfoulers and against the settlement and metamorphosis of Amphibalanus improvisus barnacle cyprids. The two isomeric compounds (-)-hopeaphenol and vaticanol B displayed a high inhibitory potential against the cyprid larvae metamorphosis at 2.8 and 1.1 µM. (-)-Hopeaphenol was also shown to be a strong inhibitor of both microalgal and bacterial adhesion at submicromolar concentrations with low toxicity. Resveratrol displayed a lower antifouling activity compared to the multimers and had higher off target toxicity against MCR-5 fibroblasts. This study illustrates the potential of natural products as a valuable source for the discovery of novel antifouling leads with low toxicity.


Assuntos
Biofilmes , Thoracica , Animais , Resveratrol/farmacologia , Fenóis
12.
Ecotoxicol Environ Saf ; 263: 115388, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37611478

RESUMO

Globally, many low to medium yielding peanut fields have the potential for further yield improvement. Low phosphorus (P) limitation is one of the significant factors curtailing Arachis hypogaea productivity in many regions. In order to demonstrate the effects of gamma-aminobutyric acid (GABA) on peanuts growing under P deficiency, we used a pot-based experiment to examine the effects of exogenous GABA on alleviating P deficiency-induced physiological changes and growth inhibition in peanuts. The key physiological parameters examined were foliar gas exchange, photochemical efficiency, proton motive force, reactive oxygen species (ROS), and adenosine triphosphate (ATP) synthase activity of peanuts under cultivation with low P (LP, 0.5 mM P) and control conditions. During low P, the cyclic electron flow (CEF) maintained the high proton gradient (∆pH) induced by low ATP synthetic activity. Applying GABA during low P conditions stimulated CEF and reduced the concomitant ROS generation and thereby protecting the foliar photosystem II (PSII) from photoinhibition. Specifically, GABA enhanced the rate of electronic transmission of PSII (ETRII) by pausing the photoprotection mechanisms including non-photochemical quenching (NPQ) and ∆pH regulation. Thus, GABA was shown to be effective in restoring peanut growth when encountering P deficiency. Exogenous GABA alleviated two symptoms (increased root-shoot ratio and photoinhibition) of P-deficient peanuts. This is possibly the first report of using exogenous GABA to restore photosynthesis and growth under low P availability. Therefore, foliar applications of GABA could be a simple, safe and effective approach to overcome low yield imposed by limited P resources (low P in soils or P-fertilizers are unavailable) for sustainable peanut cultivation and especially in low to medium yielding fields.


Assuntos
Arachis , Fotossíntese , Espécies Reativas de Oxigênio , Trifosfato de Adenosina , Fósforo/farmacologia , Ácido gama-Aminobutírico/farmacologia
13.
Molecules ; 28(13)2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37446894

RESUMO

Selenium is a main group element and an essential trace element in human health. It was discovered in selenocysteine (SeC) by Stadtman in 1974. SeC is an encoded natural amino acid hailed as the 21st naturally occurring amino acid (U) present in several enzymes and which exquisitely participates in redox biology. As it turns out, selenium bears a U-shaped toxicity curve wherein too little of the nutrient present in biology leads to disorders; concentrations that are too great, on the other hand, pose toxicity to biological systems. In light of many excellent previous reviews and the corpus of literature, we wanted to offer this current review, in which we present aspects of the clinical and biological literature and justify why we should further investigate Se-containing species in biological and medicinal contexts, especially small molecule-containing species in biomedical research and clinical medicine. Of central interest is how selenium participates in biological signaling pathways. Several clinical medical cases are recounted; these reports are mainly pertinent to human cancer and changes in pathology and cases in which the patients are often terminal. Selenium was an option chosen in light of earlier chemotherapeutic treatment courses which lost their effectiveness. We describe apoptosis, and also ferroptosis, and senescence clearly in the context of selenium. Other contemporary issues in research also compelled us to form this review: issues with CoV-2 SARS infection which abound in the literature, and we described findings with human patients in this context. Laboratory scientific studies and clinical studies dealing with two main divisions of selenium, organic (e.g., methyl selenol) or inorganic selenium (e.g., sodium selenite), are discussed. The future seems bright with the research and clinical possibilities of selenium as a trace element, whose recent experimental clinical treatments have so far involved dosing simply and inexpensively over a set of days, amounts, and time intervals.


Assuntos
COVID-19 , Selênio , Oligoelementos , Humanos , Selênio/farmacologia , Selênio/metabolismo , Oxirredução , Selenocisteína/metabolismo , Estresse Oxidativo , Apoptose , Transdução de Sinais
14.
Molecules ; 28(6)2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36985774

RESUMO

Silver nanoparticles (Ag-NPs) are most effective against pathogens and have widely been studied as antibacterial agents in commodity clothing, medical textile, and other hygiene products. However, prolonged utilization of silver and rapid mutation in bacterium stains has made them resistant to conventional silver agents. On the other hand, strict compliance against excessive utilization of toxic reagents and the current sustainability drive is forcing material synthesis toward green routes with extended functionality. In this study, we proposed an unprecedented chemical-free green synthesis of bioactive Ag-NPs without the incorporation of any chemicals. Cinnamon essential oil (ECO) was used as a bio-reducing agent with and without the mediation of lime extract. A rapid reaction completion with better shape and size control was observed in the vicinity of lime extract when incorporated into the reaction medium. The interaction of natural metabolites and citrus compounds with nanoparticles was established using Fourier transform infrared spectroscopy (FTIR) and Raman spectroscopy. The application of as-prepared nanoparticles on textiles encompasses extended bioactivity to treated fabric with infused easy-care performance. To the best of our knowledge, this is the first reported instance of utilizing bioactive silver nanoparticles as a functional finish, both as an antimicrobial and as for easy care in the absolute absence of toxic chemicals. The easy-care performance of fabric treated with lime-mediated nanoparticles was found to be 141O, which is around 26% better than bare cotton without any significant loss in fabric strength. Furthermore, to enlighten the sustainability of the process, the development traits were mapped with the United Nations Sustainable Development Goals (SDGs), which show significant influence on SDGs 3, 8, 9, and 14. With the effective suspension of microorganisms, added functionality, and eco-mapping with SDGs with the chemical-free synthesis of nanoparticles, widespread utilization can be found in various healthcare and hygiene products along with the fulfillment of sustainability needs.


Assuntos
Nanopartículas Metálicas , Nanosferas , Prata/farmacologia , Prata/química , Desenvolvimento Sustentável , Nanopartículas Metálicas/química , Antibacterianos/química , Vestuário , Espectroscopia de Infravermelho com Transformada de Fourier , Extratos Vegetais/farmacologia , Extratos Vegetais/química
15.
Angew Chem Int Ed Engl ; 62(45): e202311317, 2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-37735098

RESUMO

Solution-processed quantum dot (QD) based blue emitters are of paramount importance in the field of optoelectronics. Despite large research efforts, examples of efficient deep blue/near UV-emitting QDs remain rare due to lack of luminescent wide band gap materials and high defect densities in the existing ones. Here, we introduce a novel type of QDs based on heavy metal free gallium sulfide (Ga2 S3 ) and their core/shell heterostructures Ga2 S3 /ZnS as well as Ga2 S3 /ZnS/Al2 O3 . The photoluminescence (PL) properties of core Ga2 S3 QDs exhibit various decay pathways due to intrinsic defects, resulting in a broad overall PL spectrum. We show that the overgrowth of the Ga2 S3 core QDs with a ZnS shell results in the suppression of the intrinsic defect-mediated states leading to efficient deep-blue emission at 400 nm. Passivation of the core/shell structure with amorphous alumina yields a further enhancement of the PL quantum yield approaching 50 % and leads to an excellent optical and colloidal stability. Finally, we develop a strategy for the aqueous phase transfer of the obtained QDs retaining 80 % of the initial fluorescence intensity.

16.
Development ; 146(3)2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30665888

RESUMO

Turbidity and opaqueness are inherent properties of tissues that limit the capacity to acquire microscopic images through large tissues. Creating a uniform refractive index, known as tissue clearing, overcomes most of these issues. These methods have enabled researchers to image large and complex 3D structures with unprecedented depth and resolution. However, tissue clearing has been adopted to a limited extent due to a combination of cost, time, complexity of existing methods and potential negative impact on fluorescence signal. Here, we describe 2Eci (2nd generation ethyl cinnamate-based clearing), which can be used to clear a wide range of tissues in several species, including human organoids, Drosophila melanogaster, zebrafish, axolotl and Xenopus laevis, in as little as 1-5 days, while preserving a broad range of fluorescent proteins, including GFP, mCherry, Brainbow and Alexa-conjugated fluorophores. Ethyl cinnamate is non-toxic and can easily be used in multi-user microscope facilities. This method opens up tissue clearing to a much broader group of researchers due to its ease of use, the non-toxic nature of ethyl cinnamate and broad applicability.


Assuntos
Cinamatos/química , Corantes Fluorescentes/química , Imageamento Tridimensional/métodos , Organoides/citologia , Ambystoma mexicanum , Animais , Drosophila melanogaster , Humanos , Microscopia de Fluorescência , Xenopus laevis , Peixe-Zebra
17.
J Anat ; 241(2): 545-551, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35428985

RESUMO

The study of anatomy is largely dependent on cadaveric specimens to fulfill the tridimensional comprehension of each structure as well as the relationship between organs. Given the difficult access to fresh anatomical specimens, the constant renovation of samples for research and educational purposes is unsustainable, beyond the ethical issues involved. The standard technique for preserving specimens involves fixation and later immersion in formaldehyde, which enables a good result, but also presents elevated carcinogenic potential. Therefore, safe and efficient preservation methods are mandatory for anatomical practices and investigations. An accessible and inexpensive alternative for specimen preservation is cryodehydration. Cryodehydrated specimens can be kept dry, with no final odor, reducing the use and exposure to formaldehyde. The objective of this study was to propose a simplified step-by-step cryodehydration protocol to obtain high-quality anatomical specimens. Through consecutive freezing and thawing cycles, cryodehydration caused a weight reduction of 60%-70% and allowed anatomical preservation, while maintaining the main morphological aspects of cavitary and parenchymatous organs, muscles, or even full-body sections. The final specimens presented high durability and can be maintained for decades, preserving all relevant anatomical features.


Assuntos
Formaldeído , Técnicas Histológicas , Congelamento , Humanos
18.
Crit Rev Food Sci Nutr ; 62(7): 1782-1799, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33207938

RESUMO

Pesticide residues in the food above the maximum permissible residual limit (MRL) for safe consumption are a severe concern today. Though unit operations employed in domestic and industrial-scale processing of foods such as high-temperature decontamination and chemical washings degrade the agrochemicals and reduce toxicity, eliminating pesticides from the fresh and raw fruits and vegetables with the retainment of nutritional and organoleptic attributes demand appropriate non-thermal technologies. In this review, the potential of novel technologies like the pulsed electric field, high-pressure processing, irradiation, ozone, ultrasonication, and cold plasma for the reduction of pesticides in fruits and vegetables have been discussed in terms of their mechanism of action, playing around factors, advantages, and limitations. All the reviewed non-thermal technologies exhibited promising effects on pesticide degradation with their unique mechanism of action. Also, these techniques' potential to reduce the pesticides below MRLs and yield nontoxic metabolites in fruits and vegetables were analyzed. However, investigating the impact of the technologies on the nutritional and organoleptic quality profile of the commodities at the processing conditions causing noticeable pesticide reduction and the pathways of degradation reactions of various pesticides with each emerging technology should be studied to enhance the applicability.


Assuntos
Resíduos de Praguicidas , Praguicidas , Contaminação de Alimentos/análise , Contaminação de Alimentos/prevenção & controle , Frutas/química , Resíduos de Praguicidas/análise , Praguicidas/análise , Tecnologia , Verduras/química
19.
Molecules ; 27(17)2022 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-36080466

RESUMO

This study reports curcumin as an efficient photolarvicide against Aedes aegypti larvae under natural light illumination. Larval mortality and pupal formation were monitored daily for 21 days under simulated field conditions. In a sucrose-containing formulation, a lethal time 50 (LT50) of 3 days was found using curcumin at 4.6 mg L-1. This formulation promoted no larval toxicity in the absence of illumination, and sucrose alone did not induce larval phototoxicity. The photodegradation byproducts (intermediates) of curcumin were determined and the photodegradation mechanisms proposed. Intermediates with m/z 194, 278, and 370 were found and characterized using LC-MS. The ecotoxicity of the byproducts on non-target organisms (Daphnia, fish, and green algae) indicates that the intermediates do not exhibit any destructive potential for aquatic organisms. The results of photodegradation and ecotoxicity suggest that curcumin is environmentally safe for non-target organisms and, therefore, can be considered for population control of Ae. aegypti.


Assuntos
Aedes , Curcumina , Inseticidas , Animais , Curcumina/farmacologia , Inseticidas/farmacologia , Larva , Fotólise , Sacarose , Luz Solar
20.
Molecules ; 27(21)2022 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-36363998

RESUMO

In the past few years, the research on particle-stabilized emulsion (Pickering emulsion) has mainly focused on the usage of inorganic particles with well-defined shapes, narrow size distributions, and chemical tunability of the surfaces such as silica, alumina, and clay. However, the presence of incompatibility of some inorganic particles that are non-safe to humans and the ecosystem and their poor sustainability has led to a shift towards the development of materials of biological origin. For this reason, nano-dimensional cellulose (nanocellulose) derived from natural plants is suitable for use as a Pickering material for liquid interface stabilization for various non-toxic product formulations (e.g., the food and beverage, cosmetic, personal care, hygiene, pharmaceutical, and biomedical fields). However, the current understanding of nanocellulose-stabilized Pickering emulsion still lacks consistency in terms of the structural, self-assembly, and physio-chemical properties of nanocellulose towards the stabilization between liquid and oil interfaces. Thus, this review aims to provide a comprehensive study of the behavior of nanocellulose-based particles and their ability as a Pickering functionality to stabilize emulsion droplets. Extensive discussion on the characteristics of nanocelluloses, morphology, and preparation methods that can potentially be applied as Pickering emulsifiers in a different range of emulsions is provided. Nanocellulose's surface modification for the purpose of altering its characteristics and provoking multifunctional roles for high-grade non-toxic applications is discussed. Subsequently, the water-oil stabilization mechanism and the criteria for effective emulsion stabilization are summarized in this review. Lastly, we discuss the toxicity profile and risk assessment guidelines for the whole life cycle of nanocellulose from the fresh feedstock to the end-life of the product.


Assuntos
Ecossistema , Emulsificantes , Humanos , Emulsões/química , Emulsificantes/química , Celulose/química , Água/química
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