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1.
Acta Med Philipp ; 58(3): 82-86, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38966838

RESUMO

Although melanoma only accounts for 1% of skin cancers, it is responsible for most skin cancer deaths. Glioblastoma multiforme, a high-grade astrocytoma, is the most aggressive and devastating primary brain tumor. These two diseases remain to be the biggest therapeutic challenge in both specialties of dermatology and neuro-oncology. A 53-year-old Filipino male who presented with a 2-year history of generalized dark brown and black patches on the body developed weakness and numbness of the left extremities. Biopsy and immunohistochemical staining of the skin revealed nodular melanoma with adjacent regressing melanoma. Biopsy of the intracranial mass showed glioblastoma multiforme. One month after the partial excision of the intracranial mass, the patient expired due to brain herniation. Nodular melanoma and glioblastoma multiforme may occur concomitantly in a patient. A review of the literature suggests a shared genetic predisposition. Its existence carries a poor prognosis and requires early detection to start aggressive treatment.

2.
Biodivers Data J ; 12: e124103, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38983944

RESUMO

Background: Domitiuslusitanicus (Fage, 1931) is a troglobiont spider, endemic from caves in the largest karst massif in Portugal, the Estremenho. It was the first described cave-adapted species from Portugal, but the male of the species was only described in 1988. New information: Over the last two decades, the knowledge on the distribution of D.lusitanicus increased significantly. We assess the conservation status of D.lusitanicus, providing new information on its extent of occurrence and the anthropogenic threats and present a IUCN Red List profile. D.lusitanicus faces various anthropogenic threats, such as habitat loss, agriculture, pollution and tourism impacts. Despite a large part of its distribution is included in a Natural Park, it expands outside of the areas deemed for protection in the Natura 2000 network. This species has the widest spread distribution of all troglobionts in the Estremenho Massif; therefore, it may be used as an umbrella species for the protection of other cave-adapted species of invertebrates of the massif.

3.
Dermatitis ; 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38959123

RESUMO

Background: There is limited knowledge on international trends in topical calcineurin inhibitor (TCI) utilization. Objective: To describe international TCI utilization trends from 2012 to 2019 and evaluate the relationship of country-level economic status, geographic location, and atopic dermatitis (AD) disease burden with drug utilization. Methods: We used IQVIA MIDAS® pharmaceutical quarterly sales data to attain country-level purchasing of TCIs in grams from 2012 to 2019. A multivariable linear regression estimated the association between countries' sociodemographic index (SDI), AD disability-adjusted life year (DALY) rates, and geographic location with TCI utilization. Results: A total of 68 countries were included in our analysis. From 2012 to 2019, overall TCI utilization increased by 66% but remained 11.2 times higher in high-sociodemographic compared with low-middle/low-sociodemographic countries. SDI and geographic location were associated with greater TCI utilization in multivariable analyses, whereas AD DALY rates were not. High-SDI countries used 21,476 grams (95% confidence interval [CI]: 11,915 to 31,036) and high-middle SDI countries used 9,403 grams (95% CI: -393 to 19,200) more TCIs per 100,000 people compared with low-middle/low-SDI countries, respectively. Northern hemisphere countries used 8,588 grams more TCIs per 100,000 people (95% CI: 612 to 16,564). Conclusions: We demonstrated greater TCI utilization among high-SDI compared with lower SDI countries.

4.
Soft Matter ; 20(25): 5014-5027, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38885039

RESUMO

We investigate the direct and indirect effects of micro- and nano-kraft lignin, kL and NkL, respectively, at a quite low amount of 0.5 wt%, in poly(lactic acid) (PLA)-based composites. These renewable composites were prepared via two routes, either simple melt compounding or in situ reactive extrusion. The materials are selected and prepared using targeted methods in order to vary two variables, i.e., the size of kL and the synthetic method, while maintaining constant polymer chain lengths, L-/D-lactide isomer ratio and filler amounts. The direct/indirect effects were respectively investigated in the amorphous/semicrystalline state, as crystallinity plays in general a dominant role in polymers. The investigation involves structural, thermal and molecular mobility aspects. Non-extensive polymer-lignin interactions were recorded here, whereas the presence of the fillers led to both enhancements and suppressions of properties, e.g., glass transition, crystallization, melting temperatures, etc. The local and segmental molecular dynamics map of the said systems was constructed and is shown here for the first time, demonstrating both expected and unexpected trends. An interesting discrepancy between the trends in the calorimetric measurement against the dielectric Tg is revealed, providing indications for 'dynamical heterogeneities' in the composites as compared to neat PLA. The reactive extrusion as compared to compounding-based systems was found to exhibit stronger effects on crystallizability and mobility, most, probably due to the severe enhancement of the chains' diffusion. In general, the effects are more pronounced when employing nano-lignin compared to micro-lignin, which is the expected beneficial behaviour of nanocomposites vs. conventional composites. Interestingly, the variety of these effects can be easily manipulated by the proper selection of the preparation method and/or the thermal treatment under relatively mild conditions. The latter capability is actually desirable for processing and targeted applications and is proved here, once again, as an advantage of biobased polyesters such as PLA.

6.
Biochemistry (Mosc) ; 89(3): 462-473, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38648766

RESUMO

Structural organization of HIV-1 integrase is based on a tetramer formed by two protein dimers. Within this tetramer, the catalytic domain of one subunit of the first dimer interacts with the N-terminal domain of the second dimer subunit. It is the tetrameric structure that allows both ends of the viral DNA to be correctly positioned relative to the cellular DNA and to realize catalytic functions of integrase, namely 3'-processing and strand transfer. However, during the HIV-1 replicative cycle, integrase is responsible not only for the integration stage, it is also involved in reverse transcription and is necessary at the stage of capsid formation of the newly formed virions. It has been suggested that HIV-1 integrase is a structurally dynamic protein and its biological functions depend on its structure. Accordingly, studying interactions between the domains of integrase that provide its tetrameric structure is important for understanding its multiple functions. In this work, we investigated the role of three amino acids of the catalytic domain, I182, R187, and K188, located in the contact region of two integrase dimers in the tetramer structure, in reverse transcription and integration. It has been shown that the R187 residue is extremely important for formation of the correct integrase structure, which is necessary at all stages of its functional activity. The I182 residue is necessary for successful integration and is not important for reverse transcription, while the K188 residue, on the contrary, is involved in formation of the integrase structure, which is important for the effective reverse transcription.


Assuntos
Domínio Catalítico , Integrase de HIV , HIV-1 , Transcrição Reversa , Integração Viral , Integrase de HIV/metabolismo , Integrase de HIV/química , Integrase de HIV/genética , HIV-1/enzimologia , Humanos
7.
Ecancermedicalscience ; 18: 1665, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38439800

RESUMO

Introduction: Communication in a doctor-patient relationship constitutes a crucial aspect in medicine, and its multiple dimensions encompass a wide variety of ethical issues. Communication is particularly relevant in oncology, because it requires continually dealing with sensitive topics in one of the most highly vulnerable situations as a human: illness and proximity to death. Sexuality is one of these topics because it constitutes an area that is frequently affected by cancer and cancer treatment, which may include causing significant distress, the reinforcement of a negative self-image, relationship conflicts and a permanent memory of having cancer. The objective of this research is to describe the perception of knowledge and communications practices used by oncology doctors with respect to sexual health in the care of their patients, as well as the barriers found when it comes to confronting the topic. Methods: An exploratory quantitative, descriptive and cross-sectional study was carried out, in which a self-administered questionnaire was given to oncology doctors who practise in Chile. This questionnaire had 41 closed questions with answers on a Likert scale and was previously validated by being reviewed and applied to a pilot group of five professionals (one medical bioethics expert and four doctors in the field of oncology). The data were analysed with the SPSS statistical program v. 20, using descriptive statistics. Results: The main results show that the surveyed doctors consider sexuality to be an important part of patients' quality of life. However, this finding does not align with the practices given for including it as part of clinical care. The professionals refer as the main barriers those that are attributed to the structural functioning of the institution, giving little value to those barriers related to personal aspects or those associated with patient characteristics and/or behaviors. Conclusion: The results of this study show that, despite oncology doctors seeing sexuality as an important aspect of the quality of life of their patients, they do not include the topic in clinical care. Given that one of the main barriers is obstacles relating to the institution, it is necessary to create political institutions that create the conditions for including this area as a relevant part of cancer patient care.

8.
SLAS Discov ; 29(3): 100154, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38521503

RESUMO

Sorafenib is a multikinase inhibitor indicated for first-line treatment of unresectable hepatocellular carcinoma. Despite its widespread use in the clinic, the existing knowledge of sorafenib mode-of-action remains incomplete. To build upon the current understanding, we used the Cellular Thermal Shift Assay (CETSA) coupled to Mass Spectrometry (CETSA-MS) to monitor compound binding to its target proteins in the cellular context on a proteome-wide scale. Among the potential sorafenib targets, we identified aldehyde dehydrogenase 2 (ALDH2), an enzyme that plays a major role in alcohol metabolism. We validated the interaction of sorafenib with ALDH2 by orthogonal methods using pure recombinant protein, proving that this interaction is not mediated by other cellular components. Moreover, we showed that sorafenib inhibits ALDH2 activity, supporting a functional role for this interaction. Finally, we were able to demonstrate that both ALDH2 protein expression and activity were reduced in sorafenib-resistant cells compared to the parental cell line. Overall, our study allowed the identification of ALDH2 as a novel sorafenib target and sheds light on its potential role in both hepatocellular carcinoma and sorafenib resistance condition.


Assuntos
Aldeído-Desidrogenase Mitocondrial , Carcinoma Hepatocelular , Neoplasias Hepáticas , Proteoma , Sorafenibe , Sorafenibe/farmacologia , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/metabolismo , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Aldeído-Desidrogenase Mitocondrial/genética , Aldeído-Desidrogenase Mitocondrial/metabolismo , Linhagem Celular Tumoral , Inibidores de Proteínas Quinases/farmacologia , Antineoplásicos/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Ligação Proteica/efeitos dos fármacos
9.
Sci Rep ; 14(1): 103, 2024 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-38167527

RESUMO

Loki's Castle Vent Field (LCVF, 2300 m) was discovered in 2008 and represents the first black-smoker vent field discovered on the Arctic Mid-Ocean Ridge (AMOR). However, a comprehensive faunal inventory of the LCVF has not yet been published, hindering the inclusion of the Arctic in biogeographic analyses of vent fauna. There is an urgent need to understand the diversity, spatial distribution and ecosystem function of the biological communities along the AMOR, which will inform environmental impact assesments of future deep-sea mining activities in the region. Therefore, our aim with this paper is to provide a comprehensive inventory of the fauna at LCVF and present a first insight into the food web of the vent community. The fauna of LCVF has a high degree of novelty, with five new species previously described and another ten new species awaiting formal description. Most of the new species from LCVF are either hydrothermal vent specialists or have been reported from other chemosynthesis-based ecosystems. The highest taxon richness is found in the diffuse venting areas and may be promoted by the biogenic habitat generated by the foundation species Sclerolinum contortum. The isotopic signatures of the vent community of LCVF show a clear influence of chemosynthetic primary production on the foodweb. Considering the novel and specialised fauna documented in this paper, hydrothermal vents on the AMOR should be regarded as vulnerable marine ecosystems and protective measures must therefore be implemented, especially considering the potential threat from resource exploration and exploitation activities in the near future.


Assuntos
Ecossistema , Fontes Hidrotermais , Ecologia , Cadeia Alimentar , Biota , Oceanos e Mares
10.
Glob Chang Biol ; 30(1): e17066, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38273563

RESUMO

Groundwater is a vital ecosystem of the global water cycle, hosting unique biodiversity and providing essential services to societies. Despite being the largest unfrozen freshwater resource, in a period of depletion by extraction and pollution, groundwater environments have been repeatedly overlooked in global biodiversity conservation agendas. Disregarding the importance of groundwater as an ecosystem ignores its critical role in preserving surface biomes. To foster timely global conservation of groundwater, we propose elevating the concept of keystone species into the realm of ecosystems, claiming groundwater as a keystone ecosystem that influences the integrity of many dependent ecosystems. Our global analysis shows that over half of land surface areas (52.6%) has a medium-to-high interaction with groundwater, reaching up to 74.9% when deserts and high mountains are excluded. We postulate that the intrinsic transboundary features of groundwater are critical for shifting perspectives towards more holistic approaches in aquatic ecology and beyond. Furthermore, we propose eight key themes to develop a science-policy integrated groundwater conservation agenda. Given ecosystems above and below the ground intersect at many levels, considering groundwater as an essential component of planetary health is pivotal to reduce biodiversity loss and buffer against climate change.


Assuntos
Ecossistema , Água Subterrânea , Biodiversidade , Água Doce , Poluição Ambiental
11.
3 Biotech ; 14(2): 51, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38274848

RESUMO

To study genetic variation in Indian populations of tilapia, Oreochromis niloticus, both truss morphometrics and genetic characterization have been performed. In the present study, 88 individuals from two farm populations (GIFT and West Bengal) and one reservoir population (Gujarat) were selected to analyse variations at ten morphometric landmarks and eight microsatellite loci. Truss morphometric analysis showed PCI, PCII, and PCIII expressing 29.1%, 21.36%, and 15.48% of the variance, respectively. Results showed no clear shift in shape between the studied populations of O. niloticus, indicating low morphological variability among them. The number of microsatellite alleles ranged from 3 to 9, while expected heterozygosity (HE) and observed heterozygosity (HO) values ranged from 0.56 (WB) to 0.68 (Guj) and 0.59 (GIFT) to 0.72 (Guj), respectively. The Gujarat and West Bengal populations had the smallest pairwise distance (0.0123) between them, indicating that they were genetically closer. Individuals from GIFT, however, showed the largest distance from the other populations. DNA marker variations revealed the highest genetic variability in the Gujarat population and the lowest variability in the GIFT population. The results of this study will help establish a base population for genetic improvement program and conservation of wild populations.

12.
Mol Ecol Resour ; 24(1): e13882, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37864541

RESUMO

Transition to novel environments, such as groundwater colonization by surface organisms, provides an excellent research ground to study phenotypic evolution. However, interspecific comparative studies on evolution to groundwater life are few because of the challenge in assembling large ecological and molecular resources for species-rich taxa comprised of surface and subterranean species. Here, we make available to the scientific community an operational set of working tools and resources for the Asellidae, a family of freshwater isopods containing hundreds of surface and subterranean species. First, we release the World Asellidae database (WAD) and its web application, a sustainable and FAIR solution to producing and sharing data and biological material. WAD provides access to thousands of species occurrences, specimens, DNA extracts and DNA sequences with rich metadata ensuring full scientific traceability. Second, we perform a large-scale dated phylogenetic reconstruction of Asellidae to support phylogenetic comparative analyses. Of 424 terminal branches, we identify 34 pairs of surface and subterranean species representing independent replicates of the transition from surface water to groundwater. Third, we exemplify the usefulness of WAD for documenting phenotypic shifts associated with colonization of subterranean habitats. We provide the first phylogenetically controlled evidence that body size of males decreases relative to that of females upon groundwater colonization, suggesting competition for rare receptive females selects for smaller, more agile males in groundwater. By making these tools and resources widely accessible, we open up new opportunities for exploring how phenotypic traits evolve in response to changes in selective pressures and trade-offs during groundwater colonization.


Assuntos
Isópodes , Animais , Filogenia , Isópodes/genética , Ecossistema , DNA , Sequência de Bases
13.
Sci Rep ; 13(1): 20735, 2023 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-38007573

RESUMO

Climate change affects all ecosystems, but subterranean ecosystems are repeatedly neglected from political and public agendas. Cave habitats are home to unknown and endangered species, with low trait variability and intrinsic vulnerability to recover from human-induced disturbances. We studied the annual variability and cyclicity of temperatures in caves vis-à-vis surface in different climatic areas. We hypothesize that cave temperatures follow the average temperature pattern at the surface for each location with a slight delay in the signal, but we found three different thermal patterns occurring in caves: (1) high positive correlation and a similar thermal pattern to the surface, (2) low correlation and a slight thermal delay of the signal from the surface, and (3) high negative correlation with an extreme delay from the surface. We found daily thermal cycles in some caves, which may potentially control the circadian rhythms of cave organisms. Our results show that caves had lower thermal amplitude than the surface, and that thermal averages within caves approximately correspond to the to the annual average of surface temperature. Caves buffer external temperature and act as refugia for biota in extreme climatic events. Likewise, temperature increases at surface will lead to increment in caves, threatening subterranean biota and ecosystem services.


Assuntos
Cavernas , Ecossistema , Animais , Humanos , Temperatura , Biota , Espécies em Perigo de Extinção
14.
Nat Ecol Evol ; 7(9): 1388-1397, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37488225

RESUMO

Abyssal seafloor communities cover more than 60% of Earth's surface. Despite their great size, abyssal plains extend across modest environmental gradients compared to other marine ecosystems. However, little is known about the patterns and processes regulating biodiversity or potentially delimiting biogeographical boundaries at regional scales in the abyss. Improved macroecological understanding of remote abyssal environments is urgent as threats of widespread anthropogenic disturbance grow in the deep ocean. Here, we use a new, basin-scale dataset to show the existence of clear regional zonation in abyssal communities across the 5,000 km span of the Clarion-Clipperton Zone (northeast Pacific), an area targeted for deep-sea mining. We found two pronounced biogeographic provinces, deep and shallow-abyssal, separated by a transition zone between 4,300 and 4,800 m depth. Surprisingly, species richness was maintained across this boundary by phylum-level taxonomic replacements. These regional transitions are probably related to calcium carbonate saturation boundaries as taxa dependent on calcium carbonate structures, such as shelled molluscs, appear restricted to the shallower province. Our results suggest geochemical and climatic forcing on distributions of abyssal populations over large spatial scales and provide a potential paradigm for deep-sea macroecology, opening a new basis for regional-scale biodiversity research and conservation strategies in Earth's largest biome.


Assuntos
Biodiversidade , Ecossistema , Carbonato de Cálcio , Carbonatos
15.
J Appl Microbiol ; 134(6)2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37307226

RESUMO

AIMS: Isolation and characterization of lactobacilli from human milk and determination of their probiotic, technological, and in vitro health-promoting properties with a view to their potential use in food fermentation. METHODS AND RESULTS: Seven lactobacilli isolates were obtained from human milk and identified as Lacticaseibacillus paracasei (isolates BM1-BM6) and Lactobacillus gasseri (BM7). The isolates were examined in vitro for their technological, probiotic, and health-promoting potential. Overall, all isolates showed important technological properties based on the ability to grow in milk whey, a high to moderate acidification capacity and the absence of undesirable enzymatic activities. Lacticaseibacillus gasseri (BM7) differed from the L. paracasei isolates by the absence of several glycosidases and the inability to ferment lactose. Isolates L. paracasei BM3 and BM5 produced exopolysaccharides (EPS) from lactose. All isolates showed probiotic potential as they were tolerant to simulated gastrointestinal conditions, had high cell surface hydrophobicity, had not acquired resistance to relevant antibiotics and had no virulence characteristics. All L. paracasei showed high antimicrobial activity against various pathogenic bacteria and fungi, while L. gasseri showed a narrower spectrum of antimicrobial activity. All isolates showed health-promoting potential in vitro, as evidenced by high cholesterol-lowering activity, high ACE inhibitory activity and marked antioxidant activity. CONCLUSIONS: All strains showed excellent probiotic and technological properties for use in lactic ferments.


Assuntos
Lacticaseibacillus paracasei , Probióticos , Feminino , Humanos , Animais , Lactobacillus , Leite/microbiologia , Leite Humano , Lactose , Probióticos/farmacologia
16.
BMJ Open ; 13(6): e066897, 2023 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-37280023

RESUMO

OBJECTIVES: To (1) understand what behaviours, beliefs, demographics and structural factors predict US adults' intention to get a COVID-19 vaccination, (2) identify segments of the population ('personas') who share similar factors predicting vaccination intention, (3) create a 'typing tool' to predict which persona people belong to and (4) track changes in the distribution of personas over time and across the USA. DESIGN: Three surveys: two on a probability-based household panel (NORC's AmeriSpeak) and one on Facebook. SETTING: The first two surveys were conducted in January 2021 and March 2021 when the COVID-19 vaccine had just been made available in the USA. The Facebook survey ran from May 2021 to February 2022. PARTICIPANTS: All participants were aged 18+ and living in the USA. OUTCOME MEASURES: In our predictive model, the outcome variable was self-reported vaccination intention (0-10 scale). In our typing tool model, the outcome variable was the five personas identified by our clustering algorithm. RESULTS: Only 1% of variation in vaccination intention was explained by demographics, with about 70% explained by psychobehavioural factors. We identified five personas with distinct psychobehavioural profiles: COVID Sceptics (believe at least two COVID-19 conspiracy theories), System Distrusters (believe people of their race/ethnicity do not receive fair healthcare treatment), Cost Anxious (concerns about time and finances), Watchful (prefer to wait and see) and Enthusiasts (want to get vaccinated as soon as possible). The distribution of personas varies at the state level. Over time, we saw an increase in the proportion of personas who are less willing to get vaccinated. CONCLUSIONS: Psychobehavioural segmentation allows us to identify why people are unvaccinated, not just who is unvaccinated. It can help practitioners tailor the right intervention to the right person at the right time to optimally influence behaviour.


Assuntos
COVID-19 , Mídias Sociais , Adulto , Humanos , Estados Unidos/epidemiologia , Vacinas contra COVID-19/uso terapêutico , COVID-19/epidemiologia , COVID-19/prevenção & controle , Autorrelato , Intenção , Probabilidade , Vacinação
17.
Environ Pollut ; 330: 121749, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37127234

RESUMO

A variety of veterinary and human medicinal products (VHMPs) are found in groundwater, an often-neglected habitat inhabited by species with unique traits, stygobitic species. It is crucial to understand the effect of VHMPs on stygobitic species because they may respond differently to stressors than surface species. Our hypothesis is that groundwater species may be more susceptible to environmental contaminants due to less plasticity in their detoxification response and acquisition of energy because subterranean habitats are more stable and isolated from anthropogenic activities. We performed a battery of biomarkers associated with important physiological functions on the stygobitic asellid crustacean Proasellus lusitanicus, after a 14-day exposure to acetaminophen, a commonly used pharmaceutical and pollutant of groundwaters. Our results show a decrease in total glutathione levels and an increase in glutathione S-transferase activity, suggesting a successful detoxification response. This helps explaining why acetaminophen did not cause oxidative damage, as well as had no effect on cholinesterase activity nor in aerobic production of energy. This study shows the remarkable capacity of P. lusitanicus to tolerate sublethal concentrations of VHMP acetaminophen. Most ecotoxicological studies on stygobitic species focused on the lethal effects of these compounds. The present study focuses on consequences at sublethal concentrations. Future studies should assess the stress levels induced to better predict and estimate the impacts of contaminants on groundwater ecosystems.


Assuntos
Acetaminofen , Antioxidantes , Humanos , Acetaminofen/toxicidade , Antioxidantes/metabolismo , Ecossistema , Estresse Oxidativo , Glutationa/metabolismo
18.
Polymers (Basel) ; 15(10)2023 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-37242959

RESUMO

Poly(lactic acid) (PLA) composites with 0.5 wt% lignin or nanolignin were prepared with two different techniques: (a) conventional melt-mixing and (b) in situ Ring Opening Polymerization (ROP) by reactive processing. The ROP process was monitored by measuring the torque. The composites were synthesized rapidly using reactive processing that took under 20 min. When the catalyst amount was doubled, the reaction time was reduced to under 15 min. The dispersion, thermal transitions, mechanical properties, antioxidant activity, and optical properties of the resulting PLA-based composites were evaluated with SEM, DSC, nanoindentation, DPPH assay, and DRS spectroscopy. All reactive processing-prepared composites were characterized by means of SEM, GPC, and NMR to assess their morphology, molecular weight, and free lactide content. The benefits of the size reduction of lignin and the use of in situ ROP by reactive processing were demonstrated, as the reactive processing-produced nanolignin-containing composites had superior crystallization, mechanical, and antioxidant properties. These improvements were attributed to the participation of nanolignin in the ROP of lactide as a macroinitiator, resulting in PLA-grafted nanolignin particles that improved its dispersion.

19.
Foods ; 12(7)2023 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-37048215

RESUMO

Cheese whey fermented by lactic acid bacteria (LAB) was used to develop an edible film with antifungal properties. Five LAB strains isolated from artisanal cheeses were screened for antifungal activity and incorporated into a whey-gelatin film. Of the strains tested, Levilactobacillus brevis SJC120 showed the strongest activity against five filamentous fungi isolated from cheese and cheese-making environment, at both 10 °C and 20 °C. The cell-free supernatant from L. brevis inhibited fungal growth by more than 80%. Incorporation of bacterial cells into the film did not alter the moisture content, water vapor permeability, or mechanical and optical properties. The whey-gelatin film was also able to maintain the viability of L. brevis cells at 107 log CFU/g after 30 days at 10 °C. In cheeses wrapped with L. brevis film, the size of fungal colonies decreased by 55% to 76%. Furthermore, no significant differences (p > 0.05) were observed in cheese proteolysis or in the moisture, fat, and protein content of the cheese wrapped with films. The results showed that whey-gelatin film with L. brevis SJC120 can reduce the contamination of cheese with filamentous fungi and could be used as an alternative to conventional cheese preservation and packaging.

20.
Gene ; 864: 147294, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36858189

RESUMO

Precise estimation of genome size (GS) is vital for various genomic studies, such as deciding genome sequencing depth, genome assembly, biodiversity documentation, evolution, genetic disorders studies, duplication events etc. Animal Genome Size Database provides GS of over 2050 fish species, which ranges from 0.35 pg in pufferfish (Tetraodon nigroviridis) to 132.83 pg in marbled lungfish (Protopterus aethiopicus). The GS of majority of the fishes inhabiting waters of Indian subcontinent are still missing. In present study, we estimated GS of 51 freshwater teleost (31 commercially important, 7 vulnerable and 13 ornamental species) that ranged from 0.58 pg in banded gourami (Trichogaster fasciata) to 1.92 pg in scribbled goby (Awaous grammepomus). Substantial variation in GS was observed within the same fish orders (0.64-1.45 pg in cypriniformes, 0.70-1.41 pg in siluriformes and 0.58-1.92 pg in perciformes). We examined the relationship between the GS, chromosome number and body length across all the fishes. Body length was found to be associated with GS, whereas no relationship was noticed between the GS and the chromosome number. The analysis using ancestral information revealed haploid chromosome number 25, 27 and 24 for the most recent common ancestor of cypriniformes, siluriformes and perciformes, respectively. The study led to generation of new records on GS of 43 fish species and revalidated records for 8 species. The finding is valuable resource for further research in the areas of fish genomics, molecular ecology and evolutionary conservation genetics.


Assuntos
Peixes-Gato , Cipriniformes , Perciformes , Animais , Tamanho do Genoma , Evolução Molecular , Peixes/genética , Cromossomos/genética , Genômica , Perciformes/genética , Peixes-Gato/genética , Cipriniformes/genética , Filogenia
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