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OBJECTIVE: To investigate the effect of astaxanthin supplementation in cryopreservation media on post-thawed sperm motility, viability, morphology, reactive oxygen species (ROS), and DNA fragmentation in two cryopreservation techniques using vitrification and liquid nitrogen vapor freezing. METHODS: Thirty normozoospermic semen samples were used in the study. Post-prepared semen samples were divided into 1) non-cryopreserved control, 2) and 3) vitrified without (V) and with astaxanthin 0.5 µM (V+ATX), 4) and 5) frozen in liquid nitrogen vapor without (L) and with astaxanthin 0.5 µM (L+ATX). RESULTS: Cryopreservation using vitrification and liquid nitrogen vapor freezing significantly decreased sperm motility and viability and increased ROS levels. However, no changes were seen in sperm morphology or DNA fragmentation. The addition of astaxanthin in cryopreservation media significantly increased post-thawed motility in both vitrification (77.6±8.9% vs. 69.0±9.5% in V+ATX and V) and vapor freezing (57.0±13.3% vs. 47.7±14.6% in L+ATX and L); it significantly increased sperm viability in vitrification (75.0±11.9% vs. 65.9±11.1% in V+ATX and V), and significantly decreased ROS level in both vitrification (4.7 (2.6-8.3) RLU/sec/106 vs. 10.6 (9.4-16.0) RLU/sec/106 in V+ATX and V) and vapor freezing (4.6 (3.3-10.5) RLU/sec/106 vs. 10.3 (7.9-18.6) RLU/ sec/106 in L+ATX and L). Astaxanthin supplementation in cryopreservation media did not affect sperm morphology or DNA fragmentation. CONCLUSIONS: Astaxanthin supplementation improved post-cryopreserved sperm motility, decreased ROS levels in both vitrification and liquid nitrogen vapor freezing and improved sperm viability only in the vitrification technique.

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BACKGROUND: Evidence has suggested that cognitive decline may be a risk factor for freezing of gait (FOG) in Parkinson's disease (PD). Complex and challenging exercises have been suggested as potential rehabilitation strategies to decrease FOG severity and improve cognition; however, it is unknown whether improvement in cognition would explain decreased FOG severity following exercise. OBJECTIVE: In this secondary analysis, we evaluated the effects of the adapted resistance training with instability (ARTI-complex and challenging exercises) compared with traditional motor rehabilitation (TMR-without challenging exercises) on cognitive function in people with FOG of PD. We also verified whether cognitive improvement explains the decrease in FOG previously published. METHODS: Participants were randomized to either the experimental group (ARTI, n = 17) or the active control group (TMR, n = 15). Both training groups exercised 3 times a week for 12 weeks (80-90 minute each session). FOG severity (FOG ratio from inertial sensors during a 360° turning-in-place task), frontal lobe function (Frontal Assessment Battery [FAB]), global cognition (Montreal Cognitive Assessment [MoCA]), and attention and psychomotor speed (Digit Symbol Substitution Test [DSST]) were evaluated before and after interventions. RESULTS: Only the ARTI group improved FAB, MoCA, and DSST scores at posttraining. In addition, ARTI was more effective than TMR in improving FAB scores at posttraining. The changes in FAB scores explained the changes in FOG ratio following ARTI (R2 = .43, P < .01). CONCLUSIONS: This pilot study suggests that ARTI, a complex and challenging training, improves cognition in people with FOG of PD. Improvements in frontal lobe function with ARTI help explain decreased FOG severity.

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Patients with advanced Parkinson's disease often suffer from severe gait and balance problems, impacting quality of live and persisting despite optimization of standard therapies. The aim of this review was to systematically review the efficacy of STN-DBS programming techniques in alleviating gait disturbances in patients with advanced PD. Searches were conducted in PubMed, Embase, and Lilacs databases, covering studies published until May 2024. The review identified 36 articles that explored five distinct STN-DBS techniques aimed at addressing gait and postural instability in Parkinson's patients: low-frequency stimulation, ventral STN stimulation for simultaneous substantia nigra activation, interleaving, asymmetric stimulation and a short pulse width study. Among these, 21 articles were included in the meta-analysis, which revealed significant heterogeneity among studies. Notably, low-frequency STN-DBS demonstrated positive outcomes in total UPDRS-III score and FOG-Q, especially when combined with dopaminergic therapy. The most favorable results were found for low-frequency STN stimulation. The descriptive analysis suggests that unconventional stimulation approaches may be viable for gait problems in patients who do not respond to standard therapies.

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Conservation of the genetic diversity through skin and cartilage biobanks represents an essential strategy for maintaining biodiversity. Biobanks for the wild species of the order Rodentia have been little studied. Considering that the cryopreservation technique has specific relationships with the tissue and species of interest, we propose investigating different techniques for preserving tissue integrity and cell viability after cartilage and skin culture from Spix's yellow-toothed cavies. Subsequently, two techniques [solid-surface vitrification (SSV) vs. slow freezing (SF)] were used for cartilage and skin cryopreservation. Tissues not subjected to cryopreservation were used as controls. All tissues were evaluated for morphology and proliferation by histological techniques. Moreover, fragments were cultured, and cells were evaluated for viability, proliferation, metabolism, and apoptosis. Regardless of the cryopreservation technique, no differences were observed for the thickness of the epidermis, dermis, skin, spinous and basal layers, fibroblasts, and proliferative activity regarding the number of nucleolar organizer regions (NOR). SSV ensured better maintenance of epidermal cells, normal chondrocytes, filled gaps, collagen fibers, proliferative activity by NOR area/cell, and reduced perinuclear halos and empty gaps compared to SF. SF ensured the conservation of corneum thickness compared to the control. Although both techniques promoted cell recovery after culture, cells from SF resulted in better subconfluence time and day with cell growth around fragments compared to SSV. In conclusion, both cryopreservation techniques resulted in viable cells after culture. However, SSV promoted better maintenance of tissue morphological integrity, and SF ensured the preservation of all cell quality parameters in Spix's yellow-toothed cavies.

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MAIN CONCLUSIONS: In contrast to Neltuma species, S. tamarugo exhibited higher stress tolerance, maintaining photosynthetic performance through enhanced gene expression and metabolites. Differentially accumulated metabolites include chlorophyll and carotenoids and accumulation of non-nitrogen osmoprotectants. Plant species have developed different adaptive strategies to live under extreme environmental conditions. Hypothetically, extremophyte species present a unique configuration of physiological functions that prioritize stress-tolerance mechanisms while carefully managing resource allocation for photosynthesis. This could be particularly challenging under a multi-stress environment, where the synthesis of multiple and sequential molecular mechanisms is induced. We explored this hypothesis in three phylogenetically related woody species co-occurring in the Atacama Desert, Strombocarpa tamarugo, Neltuma alba, and Neltuma chilensis, by analyzing their leaf dehydration and freezing tolerance and by characterizing their photosynthetic performance under natural growth conditions. Besides, the transcriptomic profiling, biochemical analyses of leaf pigments, and metabolite analysis by untargeted metabolomics were conducted to study gene expression and metabolomic landscape within this challenging multi-stress environment. S. tamarugo showed a higher photosynthetic capacity and leaf stress tolerance than the other species. In this species, a multifactorial response was observed, which involves high photochemical activity associated with a higher content of chlorophylls and ß-carotene. The oxidative damage of the photosynthetic apparatus is probably attenuated by the synthesis of complex antioxidant molecules in the three species, but S. tamarugo showed the highest antioxidant capacity. Comparative transcriptomic and metabolomic analyses among the species showed the differential expression of genes involved in the biosynthetic pathways of key stress-related metabolites. Moreover, the synthesis of non-nitrogen osmoprotectant molecules, such as ciceritol and mannitol in S. tamarugo, would allow the nitrogen allocation to support its high photosynthetic capacity without compromising leaf dehydration tolerance and freezing stress avoidance.

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There are more than 200 species and subspecies of Neotropical Primates of which more than 40% are listed as threatened by the IUCN Red List of Threatened Species. Both in situ and ex situ conservation programs can benefit from the use of assisted reproductive technologies. The objective of this study was to evaluate, for the first time, cryopreservation techniques for Alouatta caraya semen. Semen samples were collected from five adult males, analyzed, and frozen in either Test-egg yolk or Test-soy lecithin-based extenders containing either 3 or 4% glycerol. Frozen-thawed samples were analyzed at 10, 40, and 80 min post-thaw. Egg yolk-based extenders were overall better than soy lecithin-based extenders. There was no significant difference between 3 and 4% glycerol in any of the parameters analyzed, however, 4% glycerol in egg yolk-based extender produced more favorable results for total motility, intact plasma membrane, lipid peroxidation, and DNA fragmentation index. This study brought novel information on semen characteristics and cryopreservation aspects for A. caraya, which can help shape future experiments to improve the outcome of frozen-thawed sperm for this and other species of Neotropical primates.

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La enfermedad de Parkinson (EP) es una condición neurodegenerativa caracterizada por alteraciones motoras que afectan principalmente el desarrollo de la marcha, produciéndose generalmente el fenómeno del congelamiento de la marcha con la posibilidad del riesgo de caída. Objetivo: Analizar los beneficios del entrenamiento de la marcha con la cinta rodante antigravitatoria en pacientes con EP. Materiales y métodos: Es un estudio pre-experimental con un solo grupo de intervención. Se llevó a cabo el entrenamiento de la marcha a través de una cinta rodante antigravitatoria (AlterG) durante un mes dividido en 2 sesiones por semana. Los parámetros de la marcha arrojados por el equipo AlterG fueron la descarga de peso, cadencia, tiempo de apoyo y longitud del paso; además se valoró el congelamiento de la marcha con el cuestionario (FOGQ) y el riesgo de caída con el test Timed Up and Go (TUG). Resultados: En los parámetros de la marcha y en el FOGQ se encontró diferencias significativas (p<0,05) entre los valores de pre y post intervención, exceptuando a la variable cadencia. El riesgo de caída disminuyó 4,6 y 4,3 segundos promedio en el test TUG en hombres y mujeres respectivamente. Conclusión: El entrenamiento de la marcha en la cinta rodante antigravitatoria mejora las condiciones de la marcha y reduce el riesgo de caídas en pacientes con EP.

Parkinson's disease (PD) is a neurodegenerative condition characterized by motor alterations that mainly affect the development of gait, generally producing the phenomenon of freezing of gait with the possibility of risk of falling. Objective: To analyze the benefits of gait training with the antigravity treadmill in patients with PD. Materials and methods: It is a pre-experimental study with a single intervention group. Gait training was carried out using an antigravity treadmill (AlterG) for one month divided into 2 sessions per week. The gait parameters returned by the AlterG team were weight unloading, cadence, support time and step length; Furthermore, freezing of gait was assessed with the questionnaire (FOGQ) and the risk of falling with the Timed Up and Go test (TUG). Results: In the gait parameters and in the FOGQ, significant differences (p<0.05) were found between the pre- and post-intervention values, except for the cadence variable. The risk of falling decreased by 4.6 and 4.3 seconds on average in the TUG test in men and women respectively. Conclusion: Antigravity treadmill gait training improves walking conditions and reduces the risk of falls in PD patients.

A doença de Parkinson (DP) é uma condição neurodegenerativa caracterizada por alterações motoras que afetam principalmente o desenvolvimento da marcha, geralmente produzindo o fenômeno de congelamento da marcha com possibilidade de risco de queda. Objetivo: Analisar os benefícios do treino de marcha com esteira antigravitacional em pacientes com DP. Materiais e métodos: Trata-se de um estudo pré-experimental com um único grupo de intervenção. O treinamento de marcha foi realizado em esteira antigravitacional (AlterG) durante um mês dividido em 2 sessões semanais. Os parâmetros de marcha retornados pela equipe AlterG foram descarga de peso, cadência, tempo de apoio e comprimento do passo; Além disso, o congelamento da marcha foi avaliado com o questionário (FOGQ) e o risco de queda com o teste Timed Up and Go (TUG). Resultados: Nos parâmetros da marcha e no FOGQ foram encontradas diferenças significativas (p<0,05) entre os valores pré e pós-intervenção, exceto na variável cadência. O risco de queda diminuiu em média 4,6 e 4,3 segundos no teste TUG em homens e mulheres respectivamente. Conclusão: O treino de marcha em esteira antigravitacional melhora as condições de marcha e reduz o risco de quedas em pacientes com DP.

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Antarctic temperature variations and long periods of freezing shaped the evolution of microorganisms with unique survival mechanisms. These resilient organisms exhibit several adaptations for life in extreme cold. In such ecosystems, microorganisms endure the absence of liquid water and exhibit resistance to freezing by producing water-binding molecules such as antifreeze proteins (AFP). AFPs modify the ice structure, lower the freezing point, and inhibit recrystallization. The objective of this study was to select and identify microorganisms isolated from different Antarctic ecosystems based on their resistance to temperatures below 0 °C. Furthermore, the study sought to characterize these microorganisms regarding their potential antifreeze adaptive mechanisms. Samples of soil, moss, permafrost, and marine sediment were collected on King George Island, located in the South Shetland archipelago, Antarctica. Bacteria and yeasts were isolated and subjected to freezing-resistance and ice recrystallization inhibition (IR) tests. A total of 215 microorganisms were isolated, out of which 118 were molecularly identified through molecular analysis using the 16S rRNA and ITS regions. Furthermore, our study identified 24 freezing-resistant isolates, including two yeasts and 22 bacteria. A total of 131 protein extracts were subjected to the IR test, revealing 14 isolates positive for AFP production. Finally, four isolates showed both freeze-resistance and IR activity (Arthrobacter sp. BGS04, Pseudomonas sp. BGS05, Cryobacterium sp. P64, and Acinetobacter sp. M1_25C). This study emphasizes the diversity of Antarctic microorganisms with the ability to tolerate freezing conditions. These microorganisms warrant further investigation to conduct a comprehensive analysis of their antifreeze capabilities, with the goal of exploring their potential for future biotechnological applications.

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A functional lateralization has been reported in control of emotional responses by the medial prefrontal cortex (mPFC). However, a hemisphere asymmetry in involvement of the mPFC in expression of fear conditioning responses has never been reported. Therefore, we investigated whether control by mPFC of freezing and cardiovascular responses during re-exposure to an aversively conditioned context is lateralized. For this, rats had guide cannulas directed to the mPFC implanted bilaterally or unilaterally in the right or left hemispheres. Vehicle or the non-selective synaptic inhibitor CoCl2 was microinjected into the mPFC 10 min before re-exposure to a chamber where the animals had previously received footshocks. A catheter was implanted into the femoral artery before the fear retrieval test for cardiovascular recordings. We observed that bilateral microinjection of CoCl2 into the mPFC reduced both the freezing behavior (enhancing locomotion and rearing) and arterial pressure and heart rate increases during re-exposure to the aversively conditioned context. Unilateral microinjection of CoCl2 into the right hemisphere of the mPFC also decreased the freezing behavior (enhancing locomotion and rearing), but without affecting the cardiovascular changes. Conversely, unilateral synaptic inhibition in the left mPFC did not affect either behavioral or cardiovascular responses during fear retrieval test. Taken together, these results suggest that the right hemisphere of the mPFC is necessary and sufficient for expression of freezing behavior to contextual fear conditioning. However, the control of cardiovascular responses and freezing behavior during fear retrieval test is somehow dissociated in the mPFC, being the former bilaterally processed.

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Despite being one of the main components of anxiety and playing a pivotal role in how an individual perceives and copes with anxiogenic situations or responds to a given treatment, trait anxiety is paradoxically omitted in most animal models of anxiety. This is problematic and particularly more concerning in models that are used to screen drugs and other treatments for specific anxiety disorders and to investigate their neurobiological mechanisms. Our group has been engaged in the search for specific anxiety-related traits in animal models of anxiety. We developed two new lines of rats with strong phenotypic divergence for high (Carioca High-conditioned Freezing [CHF]) and low (Carioca Low-conditioned Freezing [CLF]) trait anxiety as expressed in the contextual fear conditioning paradigm. Here, we summarize key behavioral, pharmacological, physiological, and neurobiological differences in one these lines, the CHF rat line, relative to randomized-cross controls and discuss how far they represent a valid and reliable animal model of generalized anxiety disorder and so high trait anxiety.

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Cryoprotectants are required to reduce damage caused to the cells due to low temperatures during the cryopreservation. Antifreeze proteins (AFP) have a well-known role in cell membrane protection, while resveratrol is a potent antioxidant. This study assessed the effect of the association of resveratrol concentrations and AFP I in a ram semen extender. Pooled semen of four rams was allocated into six treatments in a factorial arrangement: (CONT, only the semen extender); only AFP I (ANT: 0.1 µg/mL of AFP I), only resveratrol, one treatment with two levels (10 µM/mL or 50 µM/mL of resveratrol); and two treatments with the interactions, with one AFP I and one of the two levels of resveratrol (0.1 µg/mL of AFP I with 10 µM/mL resveratrol; 0.1 µg/mL of AFP I with 50 µM/mL resveratrol). No interaction between factors was observed on sperm kinetics, plasma membrane integrity, hypo-osmotic test, and mitochondrial activity parameters. There was a high probability (P = 0.06) of reducing sperm cells with functional membrane percentage in the hypo-osmotic test and increasing the percentage of sperm with high mitochondrial activity (P = 0.07) was observed in AFP presence. An interaction of AFP and resveratrol was observed in non-capacitated sperm (P = 0.009), acrosomal reaction (P = 0.034), and sperm binding (P = 0.04). In conclusion, the association of resveratrol and AFP did not improve the quality of frozen-thawed semen and even promoted deleterious effects compared to their single addition in the semen extender. The supplementation of 50 µM/mL of resveratrol improved the outcomes of frozen-thawed ram sperm, being a potential cryoprotectant.

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OBJECTIVES: To evaluate the feasibility of frozen soft tissues in simulating fresh soft tissues of pig mandibles using cone beam CT (CBCT). METHODS: Two fresh pig mandibles with soft tissues containing 2 tubes filled with a radiopaque homogeneous solution were scanned using 4 CBCT units and 2 field-of-view (FOV) sizes each. The pig mandibles were deep-frozen and scanned again. Three cross-sections were exported from each CBCT volume and grouped into pairs, with one cross-section representing a fresh and one a frozen mandible. Three radiologists compared the pairs and attributed a score to assess the relative image quality using a 5-point scale. Mean grey values and standard deviation were obtained from homogeneous areas in the tubes, compared using the Wilcoxon matched-pair signed-rank test and subjected to Pearson correlation analysis between fresh and frozen physical states (α = .05). RESULTS: Subjective evaluation revealed similarity of the CBCT image quality between fresh and frozen states. The distribution of mean grey values was similar between fresh and frozen states. Mean grey values of the frozen state in the small FOV were significantly greater than those of the fresh state (P = .037), and noise values of the frozen state in the large FOV were significantly greater than those of the fresh state (P = 0.007). Both mean grey values and noise exhibited significant and positive correlations between fresh and frozen states (P < 0.01). CONCLUSIONS: The freezing of pig mandibles with soft tissues may serve as a method to prolong their usability and working time when CBCT imaging is planned.

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This systematic review provides an overview of the history and current status of cryopreservation of fish sperm and a detailed evaluation of cryoprotocols using powdered milk. A literature search was performed in PubMed, Scopus, Web of Science, and SciELO databases. Twenty-nine articles were selected after excluding duplicate articles or articles that did not meet the eligibility criteria. Rhamdia quelen and Danio rerio were the most studied species. Slow freezing method, dry-shipper, freezing rate of -35.6°C/min, thawing in water bath (35.93°C ± 10°C), and 0.25 and 0.5 mL plastic straws were the main approaches evaluated. Methanol was the most used permeable cryoprotectant in combination with powdered milk, yielding the best results at 10% concentration. Motility rate was the main analysis performed after cryopreservation in virtually all studies, being subjectively evaluated by most authors. Powdered milk at 15% promoted the best results in the analyzed studies. For motility rate, the gains with the addition of powdered milk were observed in the orders Perciformes (Oreochromis mossambicus), Siluriformes (Pangasius pangasius, Pseudoplatystoma corruscans, and Pseudoplatystoma mataense), and Cypriniformes (Tor soro and Barbonymus gonionotus). For fertilization, gains were observed in the order Siluriformes (P. mataense) and Cypriniformes (T. soro). Sperm viability gains were observed in the orders Siluriformes (P. pangasius), Characiformes (Piaractus brachypomus), and Cypriniformes (B. gonionotus). The scientific evidence we present in this study may contribute and serve as a starting point for new and more refined studies to be developed in the field.

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ABSTRACT Introduction: Atrial fibrillation is one of the common complications of mitral valve disease. Currently, in the absence of freezing equipment, it's still impossible to fully conduct a minimally invasive Cox-maze IV procedure to treat atrial fibrillation. Methods: We analyzed the clinical data of 28 patients who underwent thoracoscopic minimally invasive mitral valve full maze surgery in our hospital from October 2021 to September 2022; 13 patients were male and 15 were female, three suffered from paroxysmal atrial fibrillation, and 25 suffered from permanent atrial fibrillation; average age was 61.88±8.30 years, and mean preoperative left atrial diameter was 47.12±8.34 mm. Isolation of left atrial posterior wall (box lesion) was completed in all patients by cut-and-sew technique and bipolar clamp ablation. Results: For these subjects, the median cardiopulmonary bypass time was 169 (109.75-202.75) minutes, aortic cross-clamping time was 106 (77.75-125.50) minutes, and ventilator assistance time was 6.5 (0-10) hours. Among them, eight subjects had the endotracheal tubes removed immediately after surgical operation. Three subjects were in the blanking period; two subjects still had atrial fibrillation at three months after operation, one of whom resumed sinus rhythm after electrical cardioversion therapy; and all the remaining 23 subjects had sinus rhythm. Conclusion: The minimally invasive cut-and-sew technique for electrical isolation of left pulmonary veins can improve sinus conversion rate of patients suffering from both mitral valve disease and atrial fibrillation. In selected subjects, it is safe and has good results in the short-term postoperative period.

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The aim of the present study was to evaluate semen cryopreservation with ACP-Lact® diluent, which consists of coconut water powder (ACP) added to goat milk powder. After thawing, the samples were evaluated for sperm kinetics, membrane evaluation and in vivo insemination. For cryopreservation, a pool was made with the ejaculate of six goats, diluted in four equal aliquots for the respective treatments: T1 (ACP-Lact®); T2 (ACP-Lact® 50%); T3 (ACP + 2.5% egg yolk) and T4 (Tris + 2.5% egg yolk). After dilution of the treatments, the samples were placed in 0.5 ml straws and chilled at a rate of -1.07°C/min. After reaching 4°C and stabilizing for one hour, the straws were placed in nitrogen vapour at -60°C for 15 minutes and then immersed in liquid nitrogen (-196ºC). The straws were thawed in a 37°C water bath and kinetic assessments were performed immediately using a computerized semen analysis program (CSA), viability (EN), membrane functionality (HOST), mitochondrial activity (DAB) and DNA integrity assessment of spermatozoa. For the in vivo experiment, ten goats were inseminated, divided into two groups of five goats each, G1 inseminated with ACP-Lact® and G2 with ACP, by fixed-time artificial insemination (FTAI). Regarding the kinetic parameters, the ACP-Lact® treatment showed higher progressive motility (PM) and sperm velocity than the other treatments (36.77%). In the VSL parameter the ACP-Lact diluent was superior to ACP and Tris. In viability the treatment with ACP-Lact® was superior to the treatment with Tris, 95% and 83% respectively. In FTAI two goats were born out of the 5 goats inseminated with ACP-Lact®. It was concluded that the use of ACP-Lact® for cryopreservation of caprine semen is efficient in maintaining seminal parameters during thawing in vitro and in vivo and proved to be a good alternative extender for the caprine species.

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The proposed study was to determine if the silver nanoparticles can be used as potential antimicrobial agents and can replace the use of conventional antibiotics in semen without affecting the motility and fertility of semen. The silver nanoparticles prepared by chemical reduction method were confirmed by determination of the wavelength of surface plasmon resonance peak and further characterized using Zetasizer by determining their size, polydispersity index, and zeta potential. The nanoparticles were assessed for antibacterial activity and their concentration was optimized for use in semen extender for cryopreservation. Cryopreserved semen was further evaluated for seminal parameters, antioxidant parameter, and microbial load. Prepared silver NPs showed a plasmon resonance peak at 417 nm wavelength. NPs were found to possess antibacterial activity and were supplemented in semen extender @ 125 and 250 µg/ml for semen cryopreservation. There was a significant increase in pre and post-freezing motility and other seminal parameters. The microbial load of frozen-thawed semen of control and supplemented groups were well within the permissible limits. Lipid peroxidation levels were reduced in NPs supplemented groups, and reactive oxygen species (ROS) levels were significantly reduced in semen supplemented with 125 µg/ml NPs. Thus it can be conclude that silver NPs can be successfully used as a substitute for antibiotics in cattle bull semen cryopreservation with good antimicrobial activity and no adverse effects on sperm characteristics.

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INTRODUCTION: Atrial fibrillation is one of the common complications of mitral valve disease. Currently, in the absence of freezing equipment, it's still impossible to fully conduct a minimally invasive Cox-maze IV procedure to treat atrial fibrillation. METHODS: We analyzed the clinical data of 28 patients who underwent thoracoscopic minimally invasive mitral valve full maze surgery in our hospital from October 2021 to September 2022; 13 patients were male and 15 were female, three suffered from paroxysmal atrial fibrillation, and 25 suffered from permanent atrial fibrillation; average age was 61.88±8.30 years, and mean preoperative left atrial diameter was 47.12±8.34 mm. Isolation of left atrial posterior wall (box lesion) was completed in all patients by cut-and-sew technique and bipolar clamp ablation. RESULTS: For these subjects, the median cardiopulmonary bypass time was 169 (109.75-202.75) minutes, aortic cross-clamping time was 106 (77.75-125.50) minutes, and ventilator assistance time was 6.5 (0-10) hours. Among them, eight subjects had the endotracheal tubes removed immediately after surgical operation. Three subjects were in the blanking period; two subjects still had atrial fibrillation at three months after operation, one of whom resumed sinus rhythm after electrical cardioversion therapy; and all the remaining 23 subjects had sinus rhythm. CONCLUSION: The minimally invasive cut-and-sew technique for electrical isolation of left pulmonary veins can improve sinus conversion rate of patients suffering from both mitral valve disease and atrial fibrillation. In selected subjects, it is safe and has good results in the short-term postoperative period.

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Meeting the ever-increasing global energy demands through sustainable and environmentally friendly means is a paramount challenge. In response to this imperative, this study is dedicated to the development of biopolymer electrolytes, which hold promise for improving the efficiency, safety, and biodegradability of energy systems. The present study aims to evaluate hydrogels synthesized from chitosan biopolymer and starch from avocado seed residues in different ratios, and dried using freeze-thawing and freeze-drying techniques. Epichlorohydrin was used as a chemical crosslinker to create a suitable degree of swelling using an ionic solution. Physical freezing crosslinking strategies such as freezing-thawing and freezing-drying were performed to generate a denser porous structure in the polymer matrix. Subsequently, synthesized electrolytes were immersed in 12 M KOH solution to improve their electrochemical properties. The effect of the different ratios of starch in the hydrogels on the structural properties of the materials was evaluated using characterization techniques such as FTIR and XRD, which allowed to confirm the crosslinking between chitosan and starch. The electrochemical performance of the hydrogels is assessed using electrochemical impedance spectroscopy. A maximum conductivity value of 0.61 S·cm-1 was achieved at room temperature. The designed materials were tested in prototype zinc-air batteries; their specific capacity value was 1618 mA h·g-1, and their obtained power density was 90 mW·cm-2. These substantial findings unequivocally underscore the potential of the synthesized hydrogels as highly promising electrolytes for the application in zinc-air battery systems.

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Freezing is an effective technology with which to maintain food quality. However, the formation of ice crystals during this process can cause damage to the cellular structure, leading to food deterioration. A good understanding of the relationship between food microstructure and ice morphology, as well as the ability to effectively measure and control ice crystals, is very useful to achieve high-quality frozen foods. Hence, a brief discussion is presented on the fundamentals/principles of optical microscopic techniques (light microscopy), electronic microscopic techniques (transmission electron microscopy (TEM) and scanning electron microscopy (SEM)), as well as other non-invasive techniques (X-rays, spectroscopy, and magnetic resonance) and their application to measuring ice formation rates and characterizing ice crystals, providing insight into the freezing mechanisms as well as direct monitoring of the entire process. And, in addition, this review compares (the negative and positive aspects of) the use of simple and cheap but destructive technologies (optical microscopy) with detailed microscopic technologies at the micro/nanometer scale but with pretreatments that alter the original sample (SEM and TEM), and non-destructive technologies that do not require sample preparation but which have high acquisition and operational costs. Also included are images and examples which demonstrate how useful an analysis using these techniques can be.