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1.
Mar Pollut Bull ; 201: 116267, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38522334

RESUMO

Weather radiosondes play a crucial role in gathering atmospheric data for weather modeling and forecasting. However, their impact on marine wildlife, particularly seabirds, has raised concerns regarding the potential threats posed by these instruments. This study aims to assess the adverse effects of weather balloons on albatrosses, with a focus on the Southwest Atlantic region. The research reveals seven cases of entanglement of radiosonde equipment, leading to severe injuries and mortality along the Southern and Southeastern coasts of Brazil. Recommendations for mitigating the environmental impact of weather balloons include the adoption of biodegradable materials in their design and the implementation of improved retrieval protocols. Furthermore, the study stresses the importance of continued monitoring and research to address the interaction of weather radiosondes with marine animals. This approach is vital for ensuring the sustainable collection of scientific data while minimizing harm to marine life and ecosystems.


Assuntos
Aves , Ecossistema , Animais , Brasil , Tempo (Meteorologia) , Animais Selvagens , Monitoramento Ambiental
2.
Front Cell Dev Biol ; 12: 1331351, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38465286

RESUMO

Introduction: Rare disorders that are genetically and clinically heterogeneous, such as mitochondrial diseases (MDs), have a challenging diagnosis. Nuclear genes codify most proteins involved in mitochondrial biogenesis, despite all mitochondria having their own DNA. The development of next-generation sequencing (NGS) technologies has revolutionized the understanding of many genes involved in the pathogenesis of MDs. In this new genetic era, using the NGS approach, we aimed to identify the genetic etiology for a suspected MD in a cohort of 450 Portuguese patients. Methods: We examined 450 patients using a combined NGS strategy, starting with the analysis of a targeted mitochondrial panel of 213 nuclear genes, and then proceeding to analyze the whole mitochondrial DNA. Results and Discussion: In this study, we identified disease-related variants in 134 (30%) analyzed patients, 88 with nuclear DNA (nDNA) and 46 with mitochondrial DNA (mtDNA) variants, most of them being pediatric patients (66%), of which 77% were identified in nDNA and 23% in mtDNA. The molecular analysis of this cohort revealed 72 already described pathogenic and 20 novel, probably pathogenic, variants, as well as 62 variants of unknown significance. For this cohort of patients with suspected MDs, the use of a customized gene panel provided a molecular diagnosis in a timely and cost-effective manner. Patients who cannot be diagnosed after this initial approach will be further selected for whole-exome sequencing. Conclusion: As a national laboratory for the study and research of MDs, we demonstrated the power of NGS to achieve a molecular etiology, expanding the mutational spectrum and proposing accurate genetic counseling in this group of heterogeneous diseases without therapeutic options.

3.
Braz J Biol ; 83: e272512, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38422258

RESUMO

This study aimed to correlate the values of liver markers with oxidative stress markers in patients with multidrug-resistant tuberculosis in the Brazilian Amazon. A total of 30 patients from the Tuberculosis clinic of a referral hospital were admitted to the study. Whole blood samples were collected for analysis of liver enzyme values and oxidative stress markers by spectrophotometry. The prevalence was male (60%) and the 18-29 age group was the most affected. Patients with multidrug-resistant tuberculosis presented catalase values with a median equal to 6.94 U/gHb and for glutathione, the median was equal to 14.76 µg∕ml. As for the values of liver enzymes (AST, ALT, Gamma-GT and Alkaline phosphatase) the patients had medians equal to 60.50 (U/L); 80 (U/L); 54 (U/L); and 100 (U/L) respectively (p<0.0001). The results suggest a hepatotoxic effect of the drug, which recommends further studies with a larger number of samples in order to investigate the predictors of liver damage in patients with multidrug-resistant tuberculosis.


Assuntos
Fígado , Tuberculose Resistente a Múltiplos Medicamentos , Humanos , Masculino , Brasil , Estresse Oxidativo , Fosfatase Alcalina/metabolismo , Fosfatase Alcalina/farmacologia , Tuberculose Resistente a Múltiplos Medicamentos/metabolismo
4.
HIV Med ; 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38092529

RESUMO

INTRODUCTION: Advancements in and accessibility to effective antiretroviral therapy has improved the life expectancy of people living with HIV, increasing the proportion of people living with HIV reaching older age (≥60 years), making this population's health-related quality of life (HRQoL) more relevant. Our aim was to identify the determinants of poor HRQoL in people living with HIV aged ≥60 years and compare them with those of their younger counterparts. METHODS: We used data from the 'Vive+' study, a cross-sectional survey conducted between October 2019 and March 2020, nested within the PISCIS cohort of people living with HIV in Catalonia and the Balearic Islands, Spain. We used the 12-item short-form survey (SF-12), divided into a physical component summary (PCS) and a mental component summary (MCS), to evaluate HRQoL. We used the least absolute shrinkage and selection operator for variable selection and used multivariable regression models to identify predictors. RESULTS: Of the 1060 people living with HIV (78.6% males) who participated in the study, 209 (19.7%) were aged ≥60 years. When comparing older people living with HIV (≥60 years) and their younger counterparts, older people exhibited a worse PCS (median 51.3 [interquartile range {IQR} 46.0-58.1] vs. 46.43 [IQR 42.5-52.7], p < 0.001) but a similar MCS (median 56.0 [IQR 49.34-64.7] vs. 57.0 [IQR 48.9-66.3], p = 0.476). In the multivariable analysis, cognitive function correlated with a PCS (ß correlation factor [ß] -0.18, p = 0.014), and depressive symptoms and satisfaction with social role correlated with an MCS (ß 0.61 and ß -0.97, respectively, p < 0.001) in people living with HIV aged ≥60 years. CONCLUSION: Depressive symptoms, poor cognitive function, and lower satisfaction with social roles predict poorer HRQoL in older people living with HIV. These factors need to be considered when designing targeted interventions.

5.
BJA Educ ; 23(11): 425-431, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37876760
7.
Sci Rep ; 13(1): 12294, 2023 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-37516810

RESUMO

Intra-Annual Density Fluctuations (IADFs) are an important wood functional trait that determine trees' ability to adapt to climatic changes. Here, we use a large tree-ring database of 11 species from 89 sites across eight European countries, covering a climatic gradient from the Mediterranean to northern Europe, to analyze how climate variations drive IADF formation. We found that IADF occurrence increases nonlinearly with ring width in both gymnosperms and angiosperms and decreases with altitude and age. Recently recorded higher mean annual temperatures facilitate the formation of IADFs in almost all the studied species. Precipitation plays a significant role in inducing IADFs in species that exhibit drought tolerance capability, and a growth pattern known as bimodal growth. Our findings suggest that species with bimodal growth patterns growing in western and southern Europe will form IADFs more frequently, as an adaptation to increasing temperatures and droughts.


Assuntos
Aclimatação , Altitude , Temperatura , Europa (Continente) , Ciclo Celular
8.
J Endocrinol Invest ; 46(12): 2525-2533, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37286864

RESUMO

PURPOSE: We aimed to study the relationship between aging and increased parathyroid hormone (PTH) values. METHODS: We performed a retrospective cross-sectional study with data from patients who underwent outpatient PTH measurements performed by a second-generation electrochemiluminescence immunoassay. We included patients over 18 years of age with simultaneous PTH, calcium, and creatinine measurements and 25-OHD measured within 30 days. Patients with glomerular filtration rate < 60 mL/min/1.73 m2, altered calcemia, 25-OHD level < 20 ng/mL, PTH values > 100 pg/mL or using lithium, furosemide or antiresorptive therapy were excluded. Statistical analyses were performed using the RefineR method. RESULTS: Our sample comprised 263,242 patients for the group with 25-OHD ≥ 20 ng/mL, that included 160,660 with 25-OHD ≥ 30 ng/mL. The difference in PTH values among age groups divided by decades was statistically significant (p < 0.0001), regardless of 25-OHD values, ≥ 20 or ≥ 30 ng/mL. In the group with 25-OHD ≥ 20 ng/mL and more than 60 years, the PTH values were 22.1-84.0 pg/mL, a different upper reference limit from the reference value recommended by the kit manufacturer. CONCLUSION: We observed a correlation between aging and PTH increase, when measured by a second-generation immunoassay, regardless of vitamin D levels, if greater than 20 ng/mL, in normocalcemic individuals without renal dysfunction.


Assuntos
Hormônio Paratireóideo , Deficiência de Vitamina D , Humanos , Adolescente , Adulto , Estudos Retrospectivos , Big Data , Estudos Transversais , Vitamina D , Cálcio
10.
Med Oral Patol Oral Cir Bucal ; 28(2): e174-e182, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36565216

RESUMO

BACKGROUND: Oral squamous cell carcinoma (OSCC) is the most prevalent malignant head and neck tumor, excluding the nonmelanoma skin cancer. Despite recent advances in the diagnosis and treatment, the disease's mortality rate is nonetheless high. The presence of isolated neoplastic cells or small clusters of up to four cells at the tumor's invasive front, named tumor budding, is associated with a worse prognosis in OSCC. Angiogenesis has also been recognized as a determining factor in the progression of malignancies and in the development of metastases. Several studies have investigated the assessment of microvascular density (MVD) as a potential prognostic factor in OSCC. This study aimed to evaluate, in OSCC, differences in MVD between tumors with high-intensity tumor budding and tumors with low-intensity or no tumor budding. In samples with high-intensity tumor budding, differences in MVD between the budding area and the area outside the budding were also evaluated. Moreover, the study assessed differences in MVD concerning clinicopathological characteristics such as sex, age, tobacco smoking, tumor location and tumor size. MATERIAL AND METHODS: One hundred and fifty [150] samples of OSCC were subjected to immunohistochemistry to assess the intensity of tumor budding (by immunostaining for multi-cytokeratin) and MVD (by immunostaining for CD34 and CD105, independently). The data were treated using descriptive and analytical statistics. RESULTS: There were no differences in MVD, assessed by immunostaining for CD34 or CD105, concerning clinicopathological characteristics such as sex, age, tobacco smoking, tumor location and tumor size (p > 0.05). Tumors with high-intensity tumor budding did not show differences in MVD, assessed by immunostaining for CD34 or CD105, when compared to tumors with low-intensity or no tumor budding (p > 0.05). However, in samples with high-intensity tumor budding, the MVD assessed by immunostaining for CD34 was higher in the budding area than in the area outside the budding (p < 0.05). This difference was not observed when MVD was assessed by immunostaining for CD105 (p > 0.05). CONCLUSIONS: The higher MVD in the budding area may be an additional indication that this is a peculiar region of the tumor, associated with biological phenomena related to tumor progression.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias Bucais , Humanos , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas de Cabeça e Pescoço , Neoplasias Bucais/patologia , Densidade Microvascular , Receptores de Superfície Celular , Endoglina , Biomarcadores Tumorais , Neovascularização Patológica/patologia , Antígenos CD34 , Prognóstico
11.
Anesthesiol Res Pract ; 2022: 2642488, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36339775

RESUMO

Background: Magnesium sulfate reduces pain scores and analgesic consumption. Its use as an analgesic resource in opioid-free or opioid-sparing techniques have also been tested. The evaluation of the antinociceptive potency of drugs and doses indirectly, through hemodynamic oscillations has been questioned. A relatively new algorithm called the plethysmographic stress index has been considered sensitive and relatively specific as a parameter for assessing the need for intraoperative analgesia. Objectives: The aim of this trial was to assess the intraoperative analgesic capacity of magnesium sulfate compared to remifentanil. The secondary objectives were propofol consumption and its latency, the consumption of opioids, ephedrine, and cisatracurium. Patients and Methods. Forty patients scheduled for post-bariatric dermolipectomy were randomly assigned to two groups to receive total intravenous anesthesia with target-controlled hypnosis induced with propofol. Analgesia was obtained in the remifentanil group with remifentanil at an initial dose of 0.2 µg·kg-1·min-1 and in the magnesium sulfate group with magnesium sulfate 40 mg·kg-1 + 10 mg·kg-1·h-1. Results: There was no statistical hemodynamic difference between the groups before and after orotracheal intubation (p = 0.062) and before and after the surgical incision (p = 0.656). There was also no statistical difference in the variation of mean arterial pressure before and after intubation (p = 0.656) and before and after the surgical incision (p = 0.911). There was similar consumption of cisatracurium, ephedrine, and postoperative opioids between the groups. Some patients in the magnesium sulfate group needed more intraoperative fentanyl and propofol, although the latency of propofol was similar in both the groups. Conclusion: We conclude that using magnesium sulfate in intravenous general anesthesia for post-bariatric dermolipectomy is related to a significant reduction in opioid consumption without compromising hemodynamic stability. Overall, PSI monitoring was helpful in driving the analgesic strategy. The use of magnesium sulfate proved to be an important adjunct in the scenario presented, allowing the use of opioids to be avoided in certain cases. We found no statistical differences in the consumption of neuromuscular blocker and vasoconstrictor. Substituting opioids for magnesium sulfate leads to an increase in propofol consumption in the scenario presented. Studies with a larger sample are needed to corroborate the results presented and evaluate other potential advantages in reducing opioid consumption.

12.
Pulmonology ; 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-36115826

RESUMO

INTRODUCTION AND OBJECTIVES: In order to improve the quality of chronic obstructive pulmonary disease (COPD) patients' care, better knowledge of clinical practice and the factors associated with patient outcomes are needed. This study aimed to evaluate the relation between clinical practice and the outcomes of patients admitted for COPD exacerbations in Portuguese hospitals. MATERIALS AND METHODS: Observational, multicentre, prospective study with a 60-days follow-up period, in 11 hospitals, including patients aged ≥ 30 years, admitted to hospital for at least 24 hours due to an acute exacerbation of COPD. Demographic and clinical data were collected, including sex, age, smoking habits, hospitalisations, pulmonary function, comorbidities, COPD symptoms, and treatment. Sixty days after discharge, COPD exacerbations management, outcome measures, and readmission data were evaluated through a structured phone follow-up interview. RESULTS: 196 patients were included (85.7% male, mean age 71.2 years), the majority admitted through the emergency service. Ex-smokers and current smokers accounted for 51% and 36%, respectively. On admission, 72.4% were on LAMA, 54.6% on LABA, and 45.5% were on LABA/LAMA. Inhaled corticosteroids (ICS) were used in 37.3% and systemic steroids (SCS) in 10.3%. 35.7 % had had at least one exacerbation, with hospitalisation, in the previous year. There was no spirometry data for 23.2%. On hospitalisation, 98.5% of patients were treated with oxygen and 38.3% with non-invasive ventilation. Additionally, 93.4% used SCS and 60.2% ICS. Antibiotics were administered to 85.2%. 95.4% of patients were discharged; 9 died, 5 of whom had a COPD-related death. The median length of stay was 12 days for discharged patients and 33 days for patients who died. At discharge, 79.1% were prescribed with LAMA, 63.6% SCS, 61.5% LABA and 55.6% LAMA+LABA. 26,2% were prescribed with ICS+LABA+LAMA. At follow-up, 44.4% had a scheduled medical appointment within the 60 days after being discharged, and 28.3% were later readmitted due to exacerbation, of whom 52.8% were hospitalised. CONCLUSIONS: The severity of COPD, particularly in exacerbations, is directly related to impaired lung function and quality of life, mortality, and significant health system costs. Knowledge about COPD exacerbations' management in acute hospital admissions in Portugal may help stimulate a national discussion and review of existing data to engage clinicians, policymakers, managers, and patients, raising awareness and promoting action on COPD.

13.
Phys Rev E ; 105(6-2): 065201, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35854579

RESUMO

In nonlinear Thomson scattering, a relativistic electron reradiates the photons of a laser pulse, converting optical light to x rays or beyond. While this extreme frequency conversion offers a promising source for probing high-energy-density materials and driving uncharted regimes of nonlinear quantum electrodynamics, conventional nonlinear Thomson scattering has inherent trade-offs in its scaling with laser intensity. Here we discover that the ponderomotive control afforded by spatiotemporal pulse shaping enables regimes of nonlinear Thomson scattering that substantially enhance the scaling of the radiated power, emission angle, and frequency with laser intensity. By appropriately setting the velocity of the intensity peak, a spatiotemporally shaped pulse can increase the power radiated by orders of magnitude. The enhanced scaling with laser intensity allows for operation at significantly lower electron energies or intensities.

14.
Braz J Biol ; 84: e248411, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35544785

RESUMO

The dopamine content in cerebral structures has been related to neuronal excitability and several approaches have been used to study this phenomenon during seizure vulnerability period. In the present work, we describe the effects of dopamine depletion after the administration of 6-hidroxidopamine (6-OHDA) into the substantia nigra pars compacta of male rats submitted to the pilocarpine model of epilepsy. Susceptibility to pilocarpine-induced status epilepticus (SE), as well as spontaneous and recurrent seizures (SRSs) frequency during the chronic period of the model were determined. Since the hippocampus is one of main structures in the development of this experimental model of epilepsy, the dopamine levels in this region were also determined after drug administration. In the first experiment, 62% (15/24) of 6-OHDA pre-treated rats and 45% (11/24) of those receiving ascorbic acid as control solution progressed to motor limbic seizures evolving to SE, after the administration of pilocarpine. Severeness of seizures during the model´s the acute period, was significantly higher in epileptic experimental rats (56.52%), than in controls (4.16%). In the second experiment, the frequency of seizures in the model's chronic phase did not significantly change between groups. Our data show that dopamine may play an important role on seizure severity in the pilo's model acute period, which seems to be due to dopamine inhibitory action on motor expression of seizure.


Assuntos
Epilepsia , Estado Epiléptico , Animais , Dopamina/efeitos adversos , Epilepsia/induzido quimicamente , Masculino , Agonistas Muscarínicos/efeitos adversos , Oxidopamina/efeitos adversos , Pilocarpina/toxicidade , Ratos , Ratos Wistar , Convulsões/induzido quimicamente , Convulsões/metabolismo , Estado Epiléptico/induzido quimicamente
15.
Braz J Med Biol Res ; 55: e11820, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35588524

RESUMO

The aim of the present study was to verify the role of lactate as a signaling molecule in cardiac tissue under physiological conditions. C57BL6/J male mice were submitted to acute running bouts on a treadmill at different exercise intensities (30, 60, and 90% of maximal speed - Smax) under the effect of two doses (0.5 and 5 mM) of α-cyano-4-hydroxycynnamate (CINN), a blocker of lactate transporters. Cardiac lactate levels, activity of the enzymes of glycolytic [hexokinase (HK) and lactate dehydrogenase (LDH)] and oxidative metabolism [citrate synthase (CS)], and expression of genes also related to metabolism [LDH, nuclear factor erythroid 2-related factor 2 (NRF-2), cytochrome oxidase IV (COX-IV), and peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α)] were evaluated. Elevated cardiac lactate levels were observed after high intensity running at 90% of Smax, which were parallel to increased activity of the HK and CS enzymes and mRNA levels of PGC-1α and COX-IV. No changes were observed in cardiac lactate levels in mice running at lower exercise intensities. Interestingly, prior intraperitoneal administration (15 min) of CINN (0.5 mM) significantly reduced cardiac lactate concentration, activities of HK and CS, and mRNA levels of PGC-1α and COX-IV in mice that ran at 90% of Smax. In addition, cardiac lactate levels were significantly correlated to both PGC-1α and COX-IV cardiac gene expression. The present study provides evidence that cardiac lactate levels are associated to gene transcription during an acute bout of high intensity running exercise.


Assuntos
Condicionamento Físico Animal , Fatores de Transcrição , Animais , Citrato (si)-Sintase/genética , Citrato (si)-Sintase/metabolismo , Citrato (si)-Sintase/farmacologia , Expressão Gênica , Ácido Láctico/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Músculo Esquelético/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Condicionamento Físico Animal/fisiologia , RNA Mensageiro/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
16.
Food Funct ; 13(9): 4993-5010, 2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-35393999

RESUMO

Thermal properties, such as thermal conductivity, specific heat capacity and latent heat, influence the melting and solidification of chocolate. The accurate prediction of these properties for micro-aerated chocolate products with varying levels of porosity ranging from 0% to 15% is beneficial for understanding and control of heat transfer mechanisms during chocolate manufacturing and food oral processing. The former process is important for the final quality of chocolate and the latter is associated with sensorial attributes, such as grittiness, melting time and flavour. This study proposes a novel multiscale finite element model to accurately predict the temporal and spatial evolution of temperature across chocolate samples. The model is evaluated via heat transfer experiments at temperatures varying from 16 °C to 45 °C. Both experimental and numerical results suggest that the rate of heat transfer within the micro-aerated chocolate is reduced by 7% when the 15% micro-aerated chocolate is compared to its solid counterpart. More specifically, on average, the thermal conductivity decreased by 20% and specific heat capacity increased by 10% for 15% micro-aeration, suggesting that micro-pores act as thermal barriers to heat flow. The latter trend is unexpected for porous materials and thus the presence of a third phase at the pore's interface is proposed which might store thermal energy leading to a delayed release to the chocolate system. The developed multiscale numerical model provides a design tool to create pore structures in chocolate with optimum melting or solidifying response.


Assuntos
Cacau , Chocolate , Chocolate/análise , Temperatura Alta , Temperatura , Condutividade Térmica
17.
Phys Rev E ; 105(3-2): 035204, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35428146

RESUMO

The nonlinear evolution of electromagnetic instabilities driven by the interpenetration of two e^{-},e^{+} plasma clouds is explored using ab initio kinetic plasma simulations. We show that the plasma clouds slow down due to both oblique and Weibel generated electromagnetic fields, which deflect the particle trajectories, transferring bulk forward momentum into transverse momentum and thermal velocity spread. This process causes the flow velocity v_{inst} to decrease approximately by a factor of sqrt[1/3] in a time interval Δt_{αB}ω_{p}∼c/(v_{fl}sqrt[α_{B}]), where α_{B} is the magnetic equipartition parameter determined by the nonlinear saturation of the instabilities, v_{fl} is the initial flow speed, and ω_{p} is the plasma frequency. For the α_{B} measured in our simulations, Δt_{αB} is close to 10 times the instability growth time. We show that as long as the plasma slab length L>v_{fl}Δt_{αB}, the plasma flow is expected to slow down by a factor close to sqrt[1/3].

18.
Chaos ; 32(2): 023119, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35232048

RESUMO

The conventional local bifurcation theory (CBT) fails to present a complete characterization of the stability and general aspects of complex phenomena. After all, the CBT only explores the behavior of nonlinear dynamical systems in the neighborhood of their fixed points. Thus, this limitation imposes the necessity of non-trivial global techniques and lengthy numerical solutions. In this article, we present an attempt to overcome these problems by including the Fisher information theory in the study of bifurcations. Here, we investigate a Riemannian metrical structure of local and global bifurcations described in the context of dynamical systems. The introduced metric is based on the concept of information distance. We examine five contrasting models in detail: saddle-node, transcritical, supercritical pitchfork, subcritical pitchfork, and homoclinic bifurcations. We found that the metric imposes a curvature scalar R on the parameter space. Also, we discovered that R diverges to infinity while approaching bifurcation points. We demonstrate that the local stability conditions are recovered from the interpretations of the curvature R, while global stability is inferred from the character of the Fisher metric. The results are a clear improvement over those of the conventional theory.

19.
Cryo Letters ; 43(4): 206-221, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36626124

RESUMO

BACKGROUND: The proteomic profile of cryopreserved in vitro produced bovine embryos is little known but can provide insights on the successful application of cryo procedures in support of animal breeding. OBJECTIVE: To identify embryonic proteins and biomarkers related to improved cryotolerance of vitrified in vitro produced bovine embryos. MATERIALS AND METHODS: Proteins were isolated from embryo pools (n = 25 embryos per replicate) and analyzed using the nanoLC - MS/MS system. Further, the UniProtKB database (Uniprot -http://www.uniprot.org/) was used for protein identification. Proteins were classified based on their molecular mass, isoelectric point, and enzymatic activity. Post-translational modification predictions and functional gene ontology analysis were performed as well. Finally, a protein-protein interaction network was created to shed light on the embryo interactome. RESULTS: Based on the MS/MS approach, 66 proteins were identified from vitrified Bos taurus embryos. The retrieved proteins were presumably annotated, which allowed a description of the qualitative and functional aspects of the embryo proteome after the vitrification process. CONCLUSION: These findings allowed us to conclude that in vitro-produced vitrified embryos expressed proteins that underlie biological processes related to reproduction, stress and lipid metabolic process, which are essential to maintain embryo viability. doi.org/10.54680/fr22410110512.


Assuntos
Criopreservação , Fertilização In Vitro , Bovinos , Animais , Fertilização In Vitro/veterinária , Criopreservação/veterinária , Criopreservação/métodos , Espectrometria de Massas em Tandem , Proteômica , Vitrificação , Blastocisto , Técnicas de Cultura Embrionária/veterinária , Técnicas de Cultura Embrionária/métodos
20.
Pol J Vet Sci ; 25(4): 635-637, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36649117

RESUMO

Ruminal acidosis is frequent in cattle fattening systems associated with grain-rich fibre-poor diets. This study aimed to assess the prevalence of ruminal lesions compatible with ruminal acidosis intensive fattening farms and its risk factors on farm. Rumens of 218 out of 1960 bullocks from six farms were classified in slaughterhouses, and the management practices and the type of feed were compared. The prevalence of lesions compatible with ruminal acidosis was high (65%), where 47% and 18% of the animals had ruminal lesions compatible with subacute and acute disease, respectively. Prevalence of lesions differed significantly between the farms, with differences in the management and feeding practices. Ruminal lesions compatible with ruminal acidosis are prevalent in cattle fattening units in Portugal and husbandry and feeding practices are likely to have an impact.


Assuntos
Acidose , Doenças dos Bovinos , Bovinos , Animais , Ração Animal/análise , Concentração de Íons de Hidrogênio , Prevalência , Rúmen , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/etiologia , Acidose/epidemiologia , Acidose/etiologia , Acidose/veterinária , Dieta/veterinária
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