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In recent decades, there has been a growing interest in optimizing the protocols intended to sperm cryopreservation in domestic animals. These protocols include initial cooling, freezing, and thawing. While different attempts have been devised to improve sperm cryopreservation, the efficiency of this reproductive biotechnology is still far from being optimal. Furthermore, while much attention in improving cooling/freezing, less emphasis has been made in how thawing can be ameliorated. Despite this, the conditions through which, upon thawing, sperm return to physiological temperatures are much relevant, given that these cells must travel throughout the female genital tract until they reach the utero-tubal junction. Moreover, the composition of the media used for artificial insemination (AI) may also affect sperm survival, which is again something that one should bear because of the long journey that sperm must make. Furthermore, sperm quality and functionality decrease dramatically during post-thawing incubation time. Added to that, the deposition of the thawed sperm suspension devoid of seminal plasma in some species during an AI is accompanied by a leukocyte migration to the uterine lumen and with it the activation of immune mechanisms. Because few reviews have focused on the evidence gathered after sperm thawing, the present one aims to compile and discuss the available information concerning ruminants, pigs and horses.
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Silty soil was widely used as filling soil materials for the replacement of expansive soil in cold regions. This paper presents a straightforward approach for the effects of wetting-drying-freezing-thawing cycles on mechanical behaviors of silty soil and expansive soil by laboratory tests. The results showed that the silty soil and expansive soil after 7th wetting-drying-freezing-thawing cycles presented the decreases of elastic modulus, failure strength, cohesion and angel of internal friction by 8.9 %â¼12.0 %, 7.7 %â¼9.0 %, 7.9 %, 4.5 % and 17.6 %â¼37.0 %, 20.5 %â¼29.4 %, 43.2 %, 13.0 %, respectively, indicating that wetting-drying-freezing-thawing cycles had little impact on mechanical property of silty soil and a great influence on that of expansive soil. Among them, the mechanical property attenuation ratio in the first three wetting-drying-freezing-thawing cycles accounted for over 90 % of the total. In the meantime, the micro-structure damage, surface crack characteristics and grain size distribution variations of expansive soil were all more significantly than these of silty soil exposed to wetting-drying-freezing-thawing cycles, which brought insight into the causes of the differences in mechanical properties for silty soil and expansive soil. It is found that the silty soil properties were more stable than expansive soil properties, and the silty soil is very effective for replacing the expansive soil below canal structures in cold regions.
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Biological drug substance (DS) is typically stored frozen to increase stability. However, freezing and thawing (F/T) of DS can impact product quality and therefore F/T processes need to be controlled. Because active F/T systems for DS bottles are lacking, freezing is often performed uncontrolled in conventional freezers, and thawing at ambient temperature or using water baths. In this study, we evaluated a novel device for F/T of DS in bottles, which can be operated in conventional freezers, generating a directed air stream around bottles. We characterized the F/T geometry and process performance in comparison to passive F/T using temperature mapping and analysis of concentration gradients. The device was able to better control the F/T process by inducing directional bottom-up F/T. As a result, it reduced cryo-concentration during freezing as well as ice mound formation. However, freezing with the device was dependent on freezer performance, i.e. prolonged process times in a highly loaded freezer were accompanied by increased cryo-concentrations. Thawing was faster compared to without the device, but had no impact on concentration gradients and was slower compared to thawing in a water bath. High-performance freezers might be required to fully exploit the potential of directional freezing with this device and allow F/T process harmonization and scaling across sites.
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This study investigated the impact of multi-frequency ultrasound-assisted (20/28/40 kHz) thawing (MUAT) at different power levels (195, 220, 245, and 270 W, respectively) on the flesh quality and protein stability of large yellow croakers. Compared with flowing water thawing (FWT) and the other MUAT sample, flesh quality results indicated that the MUAT-220 W significantly reduced (p < 0.05) thawing loss, total volatile base nitrogen (TVB-N), total free amino acids (FAAs) and thiobarbituric acid reactive substances (TBARS). Low-field nuclear magnetic resonance (LF-NMR) spectroscopy indicated that MUAT-220 W samples had higher immobilized water content and lower free water content. In addition, the MUAT-220 W sample contained higher sulfhydryl and lower carbonyl contents compared to the FWT sample. Secondary and tertiary structural results of myofibrillar proteins (MPs) showed that MUAT-220 W significantly reduced thawing damage to MPs. Therefore, MUAT-220 W improved the quality and protein stability of the large yellow croaker during the defrosting process.
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The selection of skin is crucial for the in vitro permeation test (IVPT). The purpose of this study was to investigate the influence of different freezing-thawing processes on the barrier function of skin and the transdermal permeability of granisetron and lidocaine. Rat and hairless mouse skins were thawed at three different conditions after being frozen at -20â for 9 days: thawed at 4â, room temperature (RT), and 32â. There were no significant differences in the steady-state fluxes of drugs between fresh and thawed samples, but compared with fresh skin there were significant differences in lag time for the permeation of granisetron in rat skins thawed at RT and 32â. Histological research and scanning electron microscopy images showed no obvious structural damage on frozen/thawed skin, while immunohistochemical staining and enzyme-linked immunosorbent assay for the tight junction (TJ) protein Cldn-1 showed significantly impaired epidermal barrier. It was concluded that the freezing-thawing process increases the diffusion rate of hydrophilic drugs partly due to the functional degradation of TJs. It's recommended that hairless, inbred strains and identical animal donors should be used, and the selected thawing method of skin should be validated prior to IVPT, especially for hydrophilic drugs.
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Congelamento , Camundongos Pelados , Permeabilidade , Absorção Cutânea , Pele , Animais , Pele/metabolismo , Camundongos , Absorção Cutânea/efeitos dos fármacos , Ratos , Masculino , Administração Cutânea , Lidocaína/administração & dosagem , Lidocaína/farmacocinética , Ratos Sprague-DawleyRESUMO
Stem water content serves as a pivotal parameter that reflects the plant vitality and maintains their internal water balance. Given the insufficient comprehension regarding the stem water content characteristics and its influencing factors during different stages of the overwintering period, the study focused on Acer truncatum Bunge and developed an Internet of Things (IoT)-based ecological information monitoring system. The system incorporated a proprietary stem water content sensor, allowing non-invasive, in-situ and real time acquisition of stem water content while monitoring diverse environmental parameters. We conducted a detailed elucidation of stem water content variation characteristics and their responses to diverse environmental factors. The results showed: (1) During the overwintering period, stem water content exhibited diurnal variations characterized by " daytime ascent and nighttime descent" across the three stages, exhibiting differences in the moment when the stem water content reaches extremal values and daily fluctuations ranges. Stem water content exhibited minimal fluctuations during deciduous and bud-breaking stages but experienced significant freezing-thawing alternations during the dormant stage, leading to an increased daily fluctuation range. (2) The Pearson correlation coefficients between environmental parameters and stem water content varied dynamically across stages. Path analysis revealed that during the deciduous stage, stem temperature and saturation vapor pressure deficit were dominant factors influencing stem water content; during dormant stage, air temperature and saturation vapor pressure deficit directly impacted stem water content; during the bud-breaking stage, the primary parameters affecting stem water content were saturation vapor pressure deficit and stem temperature. The study provides valuable insights into unveiling the water transport patterns within tree stems tissue and their environmental adaptation mechanisms during the overwintering period, aiding in the scientific development of winter management strategies to protect trees from severe cold and freezing damage, while fostering healthy growth in the subsequent year.
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The mobilization and redistribution of organic contaminants in groundwater is the basis and key to explore its dynamic evolution and appropriate remediation. The naturally occurring diametrical temperature gradient during freezing and thawing cycle leads to distinct behaviors of organic contaminants in groundwater. In this study, the pore-scale distribution of diesel oil in the porous media was quantitatively divided into capillary fluid state (CFS) and free fluid state (FFS) based on multiphase flow dynamics, employing low-field nuclear magnetic resonance (LF-NMR) technology. The pore-scale distribution of diesel oil depends not only on the freezing and thawing cycle but also on the temperature gradient according to LF-NMR results. The content of diesel oil in the CFS generally increases with a positive temperature gradient (e.g. freezing) compared to a negative temperature gradient (e.g. thawing), while the content of diesel oil in the FFS generally decreases. This dependence of the temperature gradient on pore-scale distribution of the diesel oil is positively correlated with the particle size of the porous medium. Furthermore, the pore-scale distribution of the diesel oil during the freezing and thawing cycle is influenced by the kinematic viscosity of the diesel oil. There is an exponential relationship between the diesel oil content and the kinematic viscosity, independent of the freezing or thawing process. During the freezing process, the diesel oil migrates from FFS to CFS, while this migration is reversed during the thawing process. The reverse migration of the diesel oil between the freezing and thawing processes leads to a spatial redistribution of the diesel oil, which is controlled by both the fluid energy and the capillary force. The present work provide meaningful guidance for the remediation of groundwater contamination in cold regions.
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Congelamento , Gasolina , Água Subterrânea , Poluentes Químicos da Água , Água Subterrânea/química , Poluentes Químicos da Água/química , Temperatura , Espectroscopia de Ressonância MagnéticaRESUMO
This work investigated the effects of five thawing methods (air thawing (AT), water thawing (WT), plasma-activated water thawing (PT), ultrasound-assisted water thawing (UWT) and ultrasound-assisted plasma-activated water thawing (UPT)) on thawing rate, quality characteristics, lipid and protein oxidation of porcine longissimus dorsi using fresh sample as control. The thawing time of UPT samples was significantly reduced by 81.15% compared to AT treatment (P < 0.05). The thawing loss of UPT samples was 1.55% significantly lower than AT samples (4.51%) (P < 0.05). In addition, UPT samples had the least cooking loss and centrifugal loss. UPT treatment reduced the conversion of bound and immobilized water to free water and resulted in more uniform water distribution. UPT treatment significantly decreased the thiobarbituric acid reactive substances (TBARS) value and carbonyl content and increased the total sulfhydryl content of the samples (P < 0.05). In conclusion, UPT treatment increased the thawing rate and retarded the lipid and protein oxidation, resulting in better maintenance of quality characteristics of porcine longissimus dorsi than other thawing methods.
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This study evaluated the effects of five thawing methods (air thawing (AT), water thawing (WT), plasma-activated water thawing (PT), ultrasound-assisted water thawing (UWT) and ultrasound-assisted plasma-activated water thawing (UPT)) on the physicochemical, thermal stability, rheological, and structural properties of porcine longissimus dorsi myofibrillar protein (MP). UPT treatment significantly improved protein solubility (73.10%) and reduced protein turbidity (0.123) compared with AT, WT, and PT treatments (P < 0.05). UPT treatment reduced the MP particle size (635.50 nm) and zeta potential (-6.38 mV) compared with AT and WT treatments (P < 0.05), which was closer to that of the fresh sample. UPT treatment also maintained the MP surface hydrophobicity and thermal stability. UPT treatment improved the MP rheological properties of the sample. In addition, UPT treatment effectively protected the MP secondary and tertiary structures. In conclusion, UPT treatment better maintained the MP physicochemical, thermal stability, rheological, and structural properties of thawed porcine longissimus dorsi. Therefore, UPT treatment can be considered as an effective thawing method.
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Maize residue retention is an effective agricultural practice for improving soil fertility in black soil region, where suffered from long freezing-thawing periods and intense freeze-thawing (FT) cycles. However, very few studies have examined the influence of maize residue retention on soil microbial communities under FT cycles. We investigated the response of soil microbial communities and co-occurrence networks to maize residue retention at different FT intensities over 12 cycles using a microcosm experiment conditioned in a temperature incubator. Our results indicated that maize residue retention induced dramatic shifts in soil archaeal, bacterial and fungal communities towards copiotroph-dominated communities. Maize residue retention consistently reduced soil fungal richness across all cycles, but this effect was weaker for archaea and bacteria. Normalized stochastic ratio analysis revealed that maize residue retention significantly enhanced the deterministic process of archaeal, bacterial and fungal communities. Although FT intensity significantly impacted soil respiration, it did not induce profound changes in soil microbial diversity and community composition. Co-occurrence network analysis revealed that maize residue retention simplified prokaryotic network, while did not impact fungal network complexity. The network robustness index suggested that maize residue retention enhanced the fungal network stability, but reduced prokaryotic network stability. Moreover, the fungal network in severe FT treatment harbored the most abundant keystone taxa, mainly being cold-adapted fungi. By identifying modules in networks, we observed that prokaryotic Module #1 and fungal Module #3 were enhanced by maize residue retention and contributed greatly to soil quality. Together, our results showed that maize residue retention exerted stronger influence on soil microbial communities and co-occurrence network patterns than FT intensity and highlighted the potential of microbial interactions in improving soil functionality.
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Bactérias , Congelamento , Fungos , Microbiologia do Solo , Zea mays , Zea mays/microbiologia , Bactérias/classificação , Bactérias/genética , Microbiota , Archaea , Solo/químicaRESUMO
Efficient thawing can preserve the quality of frozen hairtail (Trichiurus lepturus) close to that of fresh hairtail. In contrast to air thawing (AT) and radio-frequency thawing (RT), this study looked at how graphene oxide (GO) and graphene magnetic (GM) nanoparticles paired with RT affect the microstructure and protein conformation of hairtails after thawing. The results suggested that GM-RT can reduce the myofibrillar protein (MP) damage and be more effective than other thawing treatments, like AT, RT, and GO-RT, in maintaining the microstructure of hairtail. The particle size and zeta potential showed that GM-RT could reduce the aggregation of MP during the thawing process compared to other thawing methods. Moreover, the texture of the hairtail after GM-RT exhibited higher hardness (1185.25 g), elasticity (2.25 mm), and chewiness (5.75 mJ) values compared to other thawing treatments. Especially compared with RT, the GM-RT treatment displayed significant improvements in hardness (27.24%), a considerable increase in springiness (92.23%), and an increase in chewiness (57.96%). GO-RT and GM-RT significantly reduced the centrifugal loss. The scanning electron microscopy results demonstrated that the effect of GM-RT was more akin to that of a fresh sample (FS) and characterized by a well-organized microstructure. In conclusion, GM-RT effectively diminished the MP aggregation and improved the texture of thawed fish. It can be regarded as a viable alternative thawing technique to enhance MP stability, which is vital for preserving meat quality.
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In the last few years, several studies have emphasized the existence of injury-specific EV "barcodes" that could have significant importance for the precise diagnosis of different organ injuries in polytrauma patients. To expand the research potential of the NTF (network trauma research) biobank of polytraumatized patients, the NTF research group decided to further establish a biobank for EVs. However, until now, the protocols for the isolation, characterization, and storage of EVs for biobank purposes have not been conceptualized. Plasma and serum samples from healthy volunteers (n = 10) were used. Three EV isolation methods of high relevance for the work with patients' samples (ultracentrifugation, size exclusion chromatography, and immune magnetic bead-based isolation) were compared. EVs were quantified using nanoparticle tracking analysis, EV proteins, and miRNAs. The effects of different isolation solutions; the long storage of samples (up to 3 years); and the sensibility of EVs to serial freezing-thawing cycles and different storage conditions (RT, 4/-20/-80 °C, dry ice) were evaluated. The SEC isolation method was considered the most suitable for EV biobanking. We did not find any difference in the quantity of EVs between serum and plasma-EVs. The importance of particle-free PBS as an isolation solution was confirmed. Plasma that has been frozen for a long time can also be used as a source of EVs. Serial freezing-thawing cycles were found to affect the mean size of EVs but not their amount. The storage of EV samples for 5 days on dry ice significantly reduced the EV protein concentration.
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Bancos de Espécimes Biológicos , Vesículas Extracelulares , Traumatismo Múltiplo , Humanos , Vesículas Extracelulares/metabolismo , Traumatismo Múltiplo/metabolismo , Traumatismo Múltiplo/sangue , Manejo de Espécimes/métodos , Cromatografia em Gel/métodos , Masculino , Ultracentrifugação/métodos , MicroRNAs/sangue , MicroRNAs/genética , Adulto , FemininoRESUMO
Extreme temperature variations are a problem that must be faced in the practical application of microbial fuel cells (MFCs), but MFCs are not extensively described for low and even freezing temperatures. This study assessed the effect of low-temperature shock on the power generation performance and microbial community structure of MFCs. Two scales of MFCs, the small (mL-MFC) and the large (L-MFC), were constructed in the laboratory and their performance was evaluated before and after freezing at -18 °C. The experimental results demonstrate that both MFCs were capable of rapidly restoring their voltage to the previous level after thawing. For the mL-MFC (rGO/Ag), the power density recovered from 194.30 ± 10.84 mW/m2 to 195.57 ± 4.02 mW/m2 after thawing. For L-MFC (carbon felt electrodes), the power density increased significantly from the initial 1.79 mW/m2 to 173.90 mW/m2 after thawing, but the performance degradation problem after reactor amplification still needs to be solved. The sediment microbial fuel cell (SMFC) was successfully constructed and operated in a natural outdoor environment to maintain high voltage output after the period of frost. Microbial analysis indicated after the frost period, psychrotolerant microorganisms enriched on the anode, such as Flavobacterium and Psychrobacter, while the relative abundance of anaerobic methanogenic bacterium decreased. Overall, freeze-thaw operations had a non-negative impact on the performance of MFCs and provided some references for their practical applications.
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Fontes de Energia Bioelétrica , Congelamento , Reatores Biológicos , Eletricidade , EletrodosRESUMO
OBJECTIVES: In France, embryo thawing concern 45.8% of attempts at assisted reproductive technologies excluding artificial inseminations. This proportion is constantly increasing for various reasons. The main objective of this study is to compare the live birth rate following frozen blastocyst transfer (FBT) according to the initial indication for freezing. METHODS: This is a retrospective study including patients who underwent FBT between 01/01/2020 and 06/30/2022 at the Regional University Hospital Center of Tours. The results were compared (univariate and multivariate analyses) between the three main indications for freezing: freezing of the complete cohort of blastocysts for risk of ovarian hyperstimulation (=OHS), freezing of supernumerary blastocysts after fresh blastocyst transfer (BT) with pregnancy (=second request) or without pregnancy (=BT failure). Results have also been described for other indications. RESULTS: Among the 963 FBT cycles selected, 28% of live births by thawing were obtained, all indications of freezing combined. A significantly lower rate was identified in the FBT failure group compared to the OHS group. However, after adjustment, the results remained significant for the age of the patient on the freezing cycle but not for the indication for freezing. CONCLUSIONS: The outcome of a FBT does not seem significantly impacted by the indication of freezing considering the confounding factors. The prospective analysis of more data from a multicenter study would be necessary to confirm these results.
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BACKGROUND: Despite its success in the mechanical characterization of biological tissues, magnetic resonance elastography (MRE) uses ill-posed wave inversions to estimate tissue stiffness. 1-Norm has been recently introduced as a mathematical measure for the scattering of mechanical waves due to inhomogeneities based on an analysis of the delineated contours of wave displacement. PURPOSE: To investigate 1-Norm as an MRE-based quantitative biomarker of mechanical inhomogeneities arising from microscopic structural tissue alterations caused by the freeze-thaw cycle (FTC) or Alzheimer's disease (AD). METHODS: In this proof-of-concept study, we prospectively investigated excised porcine kidney (n = 6), liver (n = 6), and muscle (n = 6) before vs. after the FTC at 500-2000 Hz and excised murine brain of healthy controls (n = 3) vs. 5xFAD species with AD (n = 3) at 1200-1800 Hz using 0.5 T tabletop MRE. 1-Norm analysis was compared with conventional wave inversion. RESULTS: While the FTC reduced both stiffness and inhomogeneity in kidney, liver, and muscle tissue, AD led to lower brain stiffness but more pronounced mechanical inhomogeneity. CONCLUSION: Our preliminary results show that 1-Norm is sensitive to tissue mechanical inhomogeneity due to FTC and AD without relying on ill-posed wave inversion techniques. 1-Norm has the potential to be used as an MRE-based diagnostic biomarker independent of stiffness to characterize abnormal conditions that involve changes in tissue mechanical inhomogeneity.
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Doença de Alzheimer , Técnicas de Imagem por Elasticidade , Congelamento , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/fisiopatologia , Animais , Suínos , Camundongos , Imageamento por Ressonância Magnética , Encéfalo/diagnóstico por imagem , Fenômenos MecânicosRESUMO
BACKGROUND: Having faster plasma thawing devices could be beneficial for transfusion services, as it may improve the rapid availability of thawed plasma for bleeding patients, and it might remove the need to have extended pre-thawed plasma: thus, reducing unnecessary plasma wastage. STUDY DESIGN AND METHODS: The aims of this study were to assess (a) the thawing times and (b) in vitro haemostatic quality of thawed plasma using Barkey Plasmatherm V (PTV) at 37 and 45°C versus Barkey Plasmatherm Classic (PTC) at 37 and 45°C, Sarstedt Sahara-III Maxitherm (SS-III) at 37°C and Helmer Scientific Thermogenesis Thermoline (TT) at 37°C. Haemostatic quality was assessed using LG-Octaplas at three different time points: baseline (5 min), 24 and 120 h after thawing. RESULTS: The thawing time (SD) of 2 and 4 units was significantly different between different thawers. PTV at 45°C was the fastest method for both 2 and 4 units (7.06 min [0.68], 9.6 min [0.87], respectively). SS-III at 37°C being the slowest method (24.69 min [2.09] and 27.18 min [4.4], respectively) (p = < 0.05). Baseline measurements for all assays showed no significant difference in the prothrombin time, fibrinogen, FII, FV, protein C activity or free protein S antigen between all methods tested. However, at baseline PTV (both 37°C and 45°C) had significantly higher levels of FVII, FVIII and FXI and shortened activated partial thromboplastin time. DISCUSSION: PTV was the quickest method at thawing plasma at both 37 and at 45°C. The haemostatic quality of plasma thawed at 45 versus 37°C was not impaired. Thawing frozen plasma at 45°C should be considered.
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Criopreservação , Plasma , Humanos , Preservação de Sangue/métodos , Fatores de Tempo , Feminino , Masculino , Hemostasia , CongelamentoRESUMO
Thawing is the primary step in handling frozen aquatic products, which directly determines their end-product quality. This study firstly constructed a novel thawing method of ultrasound-assisted slightly basic electrolyzed water (UST), and its influences on the physicochemical and histological properties of shrimp, as well as the structural of myofibrillar proteins (MPs) in shrimp were evaluated. Results indicated that the UST treatment greatly reduced 48.9 % thawing time of frozen shrimp compared to traditional thawing approaches. Meanwhile, the UST effectively decreased the generation of malondialdehyde (MDA), total volatile basic nitrogen (TVB-N), and carbonyl compounds in the thawed shrimps. In addition, it significantly preserved the elasticity and integrity of muscle fiber. Notably, the UST reduced the damage of thawing to the spatial structures of MPs, thereby greatly keeping the stability of protein. All these favorable changes maintained the water holding capacity (WHC) and quality of shrimp. Therefore, the UST is a promising non-thermal thawing technology for aquatic products.
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Congelamento , Penaeidae , Água , Animais , Água/química , Penaeidae/química , Ondas Ultrassônicas , Eletrólise/métodos , Malondialdeído , Manipulação de Alimentos/métodosRESUMO
Bacteriophage fitness is determined by factors influencing both their replication within bacteria and their ability to maintain infectivity between infections. The latter becomes particularly crucial under adverse environmental conditions or when host density is low. In such scenarios, the damage experienced by viral particles could lead to the loss of infectivity, which might be mitigated if the virus undergoes evolutionary optimization through replication. In this study, we conducted an evolution experiment involving bacteriophage Qß, wherein it underwent 30 serial transfers, each involving a cycle of freezing and thawing followed by replication of the surviving viruses. Our findings show that Qß was capable of enhancing its resistance to this selective pressure through various adaptive pathways that did not impair the virus replicative capacity. Notably, these adaptations predominantly involved mutations located within genes encoding capsid proteins. The adapted populations exhibited higher resistance levels than individual viruses isolated from them, and the latter surpassed those observed in single mutants generated via site-directed mutagenesis. This suggests potential interactions among mutants and mutations. In conclusion, our study highlights the significant role of extracellular selective pressures in driving the evolution of phages, influencing both the genetic composition of their populations and their phenotypic properties.
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Congelamento , Mutação , Fagos RNA/genética , Fagos RNA/fisiologia , Adaptação Fisiológica/genética , Evolução Molecular , Replicação Viral/genética , Proteínas do Capsídeo/genéticaRESUMO
This study aimed to investigate the changes in flavor quality of roasted duck during repetitive freeze-thawing (FT, -20 â for 24 h, then at 4 â for 24 h for five cycles) of raw duck preforms. HS-SPME/GC-MS analysis showed that more than thirty volatile flavor compounds identified in roasted ducks fluctuated with freeze-thawing of raw duck preforms, while hexanal, nonanal, 1-octen-3-ol, and acetone could as potential flavor markers. Compared with the unfrozen raw duck preforms (FT-0), repetitive freeze-thawing increased the protein/lipid oxidation and cross-linking of raw duck preforms by maintaining the higher carbonyl contents (1.40 â¼ 3.30 nmol/mg), 2-thiobarbituric acid reactive substances (0.25 â¼ 0.51 mg/kg), schiff bases and disulfide bond (19.65 â¼ 30.65 µmol/g), but lower total sulfhydryl (73.37 â¼ 88.94 µmol/g) and tryptophan fluorescence intensity. Moreover, A lower protein band intensity and a transformation from α-helixes to ß-sheets and random coils were observed in FT-3 â¼ FT-5. The obtained results indicated that multiple freeze-thawing (more than two cycles) of raw duck preforms could be detrimental to the flavor quality of the roasted duck due to excessive oxidation and degradation.
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Culinária , Patos , Congelamento , Cromatografia Gasosa-Espectrometria de Massas , Paladar , Compostos Orgânicos Voláteis , Animais , Compostos Orgânicos Voláteis/análise , Manipulação de Alimentos/métodos , Oxirredução , Qualidade dos Alimentos , Substâncias Reativas com Ácido Tiobarbitúrico/análiseRESUMO
Palatal solitary neurofibromas (SNFs), not linked to neurofibromatosis type 1, are uncommon. A 45-year-old female with a palatal SNF underwent non-surgical treatment using liquid nitrogen cryotherapy (LNC). The lesion, initially 9 x 8 x 3 mm, was treated with two 1-2 minute freeze-thaw cycles, progressively extended to two 2-2 minute freeze-thaw cycles to address the refractoriness. After four LNC sessions, the lesion resolved without recurrence at five months. This case demonstrates LNC's efficacy as a surgical alternative for palatal SNF, offering a non-invasive option for patients declining surgery. The positive outcome warrants further research into LNC's role in managing similar benign lesions.