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1.
PLoS One ; 19(6): e0301002, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38848328

RESUMO

The known diversity of European middle and late Miocene hominids has increased significantly during the last decades. Most of these great apes were frugivores in the broadest sense, ranging from soft fruit frugivores most like chimpanzees to hard/tough object feeders like orangutans, varying in size from larger than siamangs (over 17 kg) to larger than most chimpanzees (~60-70 kg). In contrast to the frequent sympatry of hominoids in the early-to-middle Miocene of Africa, in no European Miocene locality more than one hominid taxon has been identified. Here we describe the first case of hominid sympatry in Europe from the 11.62 Ma old Hammerschmiede HAM 5 level, best known from its excellent record of Danuvius guggenmosi. The new fossils are consistent in size with larger pliopithecoids but differ morphologically from any pliopithecoid and from Danuvius. They are also distinguished from early and middle Miocene apes, share affinities with late Miocene apes, and represent a small hitherto unknown late Miocene ape Buronius manfredschmidi. With an estimated body mass of about 10 kg it represents the smallest known hominid taxon. The relative enamel thickness of Buronius is thin and contrasts with Danuvius, whose enamel is twice as thick. The differences between Buronius and Danuvius in tooth and patellar morphology, enamel thickness and body mass are indicative of differing adaptations in each, permitting resource partitioning, in which Buronius was a more folivorous climber.


Assuntos
Fósseis , Hominidae , Animais , Fósseis/anatomia & histologia , Hominidae/anatomia & histologia , Alemanha
3.
Integr Org Biol ; 6(1): obae014, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38741667

RESUMO

The hyoid apparatus of tetrapods is highly diverse in its morphology. It plays an important role in feeding, breathing, sound production, and various other behaviors. Among turtles, the diversity of the hyoid apparatus has been recurrently linked to their habitat. The ossification of the hyoid corpus is often the main trait used in correlations with "niche" occupancy, an ossified corpus being associated with aquatic environments and a cartilaginous corpus with terrestrial life. Most studies conducted so far have focused on species belonging to Testudinoidea, the clade that occupies the biggest diversity of habitats (i.e., terrestrial, semi-terrestrial, and aquatic animals), while other turtle lineages have been largely understudied. We assessed the adult anatomy of the hyoid apparatus of 92 turtle species from all "families", together with ossification sequences from embryological series of 11 species, some described for the first time here. Using nearly 40 different discrete anatomical characters, we discuss the evolutionary patterns and the biological significance of morphological transformations in the turtle hyoid elements. Morphological changes are strongly associated to feeding modes, with several instances of convergent evolution within and outside the Testudines clade, and are not as strongly connected to habitat as previously thought. Some of the hyoid character states we describe are diagnostic of specific turtle clades, thus providing phylogenetically relevant information.


El aparato hyoideo de los tetrápodos es muy diverso en su morfología. El mismo desempeña un papel importante en la alimentación, la respiración, la producción de sonidos y otras funciones. En las tortugas, la diversidad del aparato hyoideo se ha relacionado con el hábitat. La osificación del cuerpo hyoideo es a menudo el rasgo principal utilizado en correlaciones con la ocupación de "nichos"; un cuerpo osificado se asocia con ambientes acuáticos y un cuerpo cartilaginoso con la vida terrestre. La mayoría de los estudios realizados se han centrado en especies pertenecientes a Testudinoidea, el clado que ocupa la mayor diversidad de hábitats (terrestre, semiterrestre y acuático), mientras que otros linajes de tortugas han sido poco estudiados. Evaluamos la anatomía adulta del aparato hyoideo de 92 especies de tortugas de todas las "familias", junto con secuencias de osificación de series embriológicas de once especies, algunas descritas por primera vez aquí. Utilizando casi 40 caracteres anatómicos discretos diferentes, discutimos los patrones evolutivos y el significado biológico de lastransformaciones morfológicas en los elementos hyoideos de las tortugas. Los cambios morfológicos están asociados con los modos de alimentación, con varios casos de convergencia dentro y fuera del clado Testudines; la asociación con el hábitat no es tan robusta como se ha hipotetizado. Algunos de los estados de caracteres que describimos son diagnósticos de clados de tortugas específicos, proporcionando así información filogenéticamente relevante.

4.
Artigo em Inglês | MEDLINE | ID: mdl-38770701

RESUMO

PURPOSE: Rotational ankle instability can be diagnosed in up to 18% of cases of chronic lateral ankle instability. It is characterised by an abnormal increase of talar rotation within the tibiofibular mortise, due to an injury in the most anterior component of the deltoid ligament secondary to a chronic deficiency of the lateral collateral ligament. The aim of this prospective observational study was to investigate the clinical outcomes following arthroscopic all-inside medial and lateral ligament reconstruction for rotational ankle instability. METHODS: A prospective observational study of consecutive patients undergoing arthroscopic all-inside medial and lateral ligament reconstruction for rotational ankle instability with minimum 6-month follow-up. The primary outcome was a validated patient-reported outcome measure (PROM), the Manchester-Oxford Foot Questionnaire. Secondary outcomes included the EQ-5D, European Foot and Ankle Society score and complications. RESULTS: Between 2020 and 2023, 12 patients underwent primary arthroscopic all-inside medial and lateral ligament reconstruction for rotational ankle instability with pre- and post-operative PROMs available for all 12 patients. The mean ± standard deviation age was 33.9 ± 7.2 years and the mean follow-up was 1.9 ± 1.2 (range: 0.5-3.8, interquartile range: 0.9-3.0) years. There was a significant improvement in all Manchester-Oxford Foot Questionnaire domain scores (p < 0.05): Index 53.1 ± 19.1 to 26.4 ± 27.6, Pain 46.7 ± 20.3 to 26.2 ± 26.8, Walking/Standing 58.7 ± 26.0 to 27.0 ± 30.0 and Social Interaction 51.2 ± 19.5 to 25.6 ± 30.1. There were improvements in EQ-5D-5L Index, VAS and VAS Pain; however, these were not statistically significant. There was one complication-a superficial peroneal nerve injury which resolved with a corticosteroid injection. CONCLUSION: The arthroscopic all-inside medial and lateral ligament reconstruction technique is a reliable and safe method for treating rotational ankle instability, demonstrating significant improvement in PROMs at a mean 1.9-year follow-up. LEVEL OF EVIDENCE: Level IV.

5.
Biol Lett ; 20(3): 20240010, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38471564

RESUMO

Overkill of large mammals is recognized as a key driver of Pleistocene megafaunal extinctions in the Americas and Australia. While this phenomenon primarily affected mega-mammals, its impact on large Quaternary reptiles has been debated. Freshwater turtles, due to the scarcity of giant forms in the Quaternary record, have been largely neglected in such discussions. Here we present a new giant podocnemidid turtle, Peltocephalus maturin sp. nov., from the Late Pleistocene Rio Madeira Formation in the Brazilian Amazon, that challenges this assumption. Morphological and phylogenetic analyses of the holotype, a massive partial lower jaw, reveal close affinities to extant Amazonian species and suggest an omnivorous diet. Body size regressions indicate Pe. maturin possibly reached about 180 cm in carapace length and is among the largest freshwater turtles ever found. This finding presents the latest known occurrence of giant freshwater turtles, hinting at coexistence with early human inhabitants in the Amazon.


Assuntos
Tartarugas , Animais , Humanos , Filogenia , Brasil , Répteis , Água Doce , Mamíferos
6.
Sci Rep ; 14(1): 1771, 2024 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-38245567

RESUMO

Nano and microfluidic technologies have shown great promise in the development of controlled drug delivery systems and the creation of microfluidic devices with logic-like functionalities. Here, we focused on investigating a droplet-based logic gate that can be used for automating medical diagnostic assays. This logic gate uses viscoelastic fluids, which are particularly relevant since bio-fluids exhibit viscoelastic properties. The operation of the logic gate is determined by evaluating various parameters, including the Weissenberg number, the Capillary number, and geometric factors. To effectively classify the logic gates operational conditions, we employed a deep learning classification to develop a reduced-order model. This approach accelerates the prediction of operating conditions, eliminating the need for complex simulations. Moreover, the deep learning model allows for the combination of different AND/OR branches, further enhancing the versatility of the logic gate. We also found that non-operating regions, where the logic gate does not function properly, can be transformed into operational regions by applying an external force. By utilizing an electrical induction technique, we demonstrated that the application of an electric field can repel or attract droplets, thereby improving the performance of the logic gate. Overall, our research shows the potential of the droplet-based logic gates in the field of medical diagnostics. The integration of deep learning classification algorithms enables rapid evaluation of operational conditions and facilitates the design of complex logic circuits. Additionally, the introduction of external forces and electrical induction techniques opens up new possibilities for enhancing the functionality and reliability of these logic gates.

7.
J Dairy Sci ; 107(2): 870-882, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37769943

RESUMO

Diet formulation in a pasture-based dairy system is a challenge as the quality and quantity of available pasture, which generally constitutes the base diet, is constantly changing. The objective of this paper is to cover a more in-depth review of the nutritional characteristics of pasture-based diets, identifying potential system, plant, and animal factors that condition pasture dietary inclusion in dairy cows. In practice, there is a wide diversity of pasture-based systems with predominant to minimal use of pasture requiring a more specific classification that potentially considers the amount and time of access to pasture, access to housing, length of grazing season, seasonality of calving, and level and method of supplementation. There are important differences in the nutritional quality between pasture species and even cultivars. However, under management practices that promote maintenance of pasture in a vegetative state as well as controlling the availability of pasture, it is possible to achieve high dry matter intakes (∼2.9%-3.4% of live weight) of pasture with moderate to high diet energy density, protein supply, and digestibility. The amount of pasture to include in the diet will depend on several factors, such as the type of production system, the cost of supplementary feeds, and the farmer's objectives, but inclusions of ∼40% to 50% of the diet seem to potentially reduce costs while apparently not limiting voluntary feed intake. Considering that there seems to be a continuum of intermediate management systems, a better understanding of the factors inherent to the feed ingredients used, as well as the use of nutrients by cows, and potential interactions between animal × system should be addressed in greater depth. This requires a meta-analysis approach, but given the diversity of the pasture-based system in practice, the existing information is highly fragmented. A clear definition of "subsystems" is necessary to direct the future research and development of mechanistic models.


Assuntos
Lactação , Leite , Animais , Bovinos , Feminino , Humanos , Ração Animal/análise , Indústria de Laticínios/métodos , Dieta/veterinária , Ingestão de Alimentos , Leite/metabolismo
8.
Braz. j. biol ; 842024.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469248

RESUMO

Abstract Hibernation is a natural condition of animals that lives in the temperate zone, although some tropical lizards also experience hibernation annually, such as the lizard native from South America, Salvator merianae, or tegu lizard. Even though physiological and metabolic characteristic associated with hibernation have been extensively studied, possible alterations in the red blood cells (RBC) integrity during this period remains unclear. Dehydration and fasting are natural consequences of hibernating for several months and it could be related to some cellular modifications. In this study, we investigated if the osmotic tolerance of RBCs of tegu lizard under hibernation is different from the cells obtained from animals while normal activity. Additionally, we indirectly investigated if the RBCs membrane of hibernating tegus could be associated with oxidation by quantifying oxidized biomolecules and the activity of antioxidant enzymes. Our findings suggest that RBCs are more fragile during the hibernation period, although we did not find evidence of an oxidative stress scenario associated with the accentuated fragility. Even though we did not exclude the possibility of oxidative damage during hibernation, we suggested that an increased RBCs volume as a consequence of hypoosmotic blood during hibernation could also affect RBCs integrity as noted.


Resumo A hibernação é uma condição natural dos animais que vivem na zona temperada, embora alguns lagartos tropicais também experenciem hibernação anualmente, como é o caso do lagarto nativo da América do Sul, Salvator merianae ou teiú. Embora as características fisiológicas e metabólicas associadas à hibernação tenham sido amplamente estudadas, possíveis alterações na integridade das hemácias durante esse período ainda permanecem obscuras. A desidratação e o jejum são consequências naturais da hibernação por vários meses e podem estar relacionadas a algumas modificações celulares. Neste estudo, investigamos se a tolerância osmótica de hemácias do lagarto teiú sob hibernação são diferentes das células obtidas de animais em atividade normal. Além disso, investigamos indiretamente por meio da quantificação de biomoléculas oxidadas e da atividade de enzimas antioxidantes se a membrana das hemácias dos teiús em hibernação poderia estar associada à oxidação. Nossos resultados sugerem que as hemácias possuem maior fragilidade durante o período de hibernação, embora não tenhamos encontrado evidências de um cenário de estresse oxidativo associado à essa fragilidade acentuada. Embora não tenhamos excluído a possibilidade de dano oxidativo durante a hibernação, sugerimos que um aumento no volume das hemácias como consequência de sangue hipoosmótico durante a hibernação também poderia afetar a integridade de hemácias, tal como foi observado.

9.
Braz. j. biol ; 84: e249617, 2024. graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1345540

RESUMO

Abstract Hibernation is a natural condition of animals that lives in the temperate zone, although some tropical lizards also experience hibernation annually, such as the lizard native from South America, Salvator merianae, or "tegu" lizard. Even though physiological and metabolic characteristic associated with hibernation have been extensively studied, possible alterations in the red blood cells (RBC) integrity during this period remains unclear. Dehydration and fasting are natural consequences of hibernating for several months and it could be related to some cellular modifications. In this study, we investigated if the osmotic tolerance of RBCs of tegu lizard under hibernation is different from the cells obtained from animals while normal activity. Additionally, we indirectly investigated if the RBCs membrane of hibernating tegus could be associated with oxidation by quantifying oxidized biomolecules and the activity of antioxidant enzymes. Our findings suggest that RBCs are more fragile during the hibernation period, although we did not find evidence of an oxidative stress scenario associated with the accentuated fragility. Even though we did not exclude the possibility of oxidative damage during hibernation, we suggested that an increased RBCs volume as a consequence of hypoosmotic blood during hibernation could also affect RBCs integrity as noted.


Resumo A hibernação é uma condição natural dos animais que vivem na zona temperada, embora alguns lagartos tropicais também experenciem hibernação anualmente, como é o caso do lagarto nativo da América do Sul, Salvator merianae ou "teiú". Embora as características fisiológicas e metabólicas associadas à hibernação tenham sido amplamente estudadas, possíveis alterações na integridade das hemácias durante esse período ainda permanecem obscuras. A desidratação e o jejum são consequências naturais da hibernação por vários meses e podem estar relacionadas a algumas modificações celulares. Neste estudo, investigamos se a tolerância osmótica de hemácias do lagarto teiú sob hibernação são diferentes das células obtidas de animais em atividade normal. Além disso, investigamos indiretamente por meio da quantificação de biomoléculas oxidadas e da atividade de enzimas antioxidantes se a membrana das hemácias dos teiús em hibernação poderia estar associada à oxidação. Nossos resultados sugerem que as hemácias possuem maior fragilidade durante o período de hibernação, embora não tenhamos encontrado evidências de um cenário de estresse oxidativo associado à essa fragilidade acentuada. Embora não tenhamos excluído a possibilidade de dano oxidativo durante a hibernação, sugerimos que um aumento no volume das hemácias como consequência de sangue hipoosmótico durante a hibernação também poderia afetar a integridade de hemácias, tal como foi observado.


Assuntos
Animais , Hibernação , Lagartos , Oxirredução , Estresse Oxidativo , Eritrócitos
10.
Nanomaterials (Basel) ; 13(17)2023 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-37686955

RESUMO

By taking advantage of the outstanding intrinsic optoelectronic properties of perovskite-based photovoltaic materials, together with the strong near-infrared (NIR) absorption and electronic confinement in PbS quantum dots (QDs), sub-bandgap photocurrent generation is possible, opening the way for solar cell efficiencies surpassing the classical limits. The present study shows an effective methodology for the inclusion of high densities of colloidal PbS QDs in a MAPbI3 (methylammonium lead iodide) perovskite matrix as a means to enhance the spectral window of photon absorption of the perovskite host film and allow photocurrent production below its bandgap. The QDs were introduced in the perovskite matrix in different sizes and concentrations to study the formation of quantum-confined levels within the host bandgap and the potential formation of a delocalized intermediate mini-band (IB). Pronounced sub-bandgap (in NIR) absorption was optically confirmed with the introduction of QDs in the perovskite. The consequent photocurrent generation was demonstrated via photoconductivity measurements, which indicated IB establishment in the films. Despite verifying the reduced crystallinity of the MAPbI3 matrix with a higher concentration and size of the embedded QDs, the nanostructured films showed pronounced enhancement (above 10-fold) in NIR absorption and consequent photocurrent generation at photon energies below the perovskite bandgap.

11.
Atherosclerosis ; 379(Suppl 1): S118-S118, Aug. 2023.
Artigo em Inglês | CONASS, Sec. Est. Saúde SP, SESSP-IDPCPROD, Sec. Est. Saúde SP | ID: biblio-1510720

RESUMO

BACKGROUND AND AIMS: Apolipoprotein B plays a crucial role in regulating plasma cholesterol by mediating the interaction of low-density lipoprotein (LDL) with LDL receptors in the liver. Inherited mutations in this gene may increase the risk of developing premature atherosclerotic cardiovascular disease, especially in individuals with familial hypercholesterolemia type 2 (FH2). The aim of this study is to identify APOB variants that may indicate pathogenicity in a sample of the Brazilian population using a data bank exome sequencing study by NGS in a Brazilian population phenotypically diagnosed by clinical and laboratory profile. This finding is going to improve genetic hypercholesteremia diagnosis. METHODS: High-quality DNA samples (n»300) were sequenced using an exon-targeted gene sequencing (ETGS) strategy to identify variants in FHrelated genes. Pathogenicity classification was based on criteria established by the American College of Medical Genetics and Genomics (ACMG), also using information from ClinVar and pathogenicity scores from previous association studies. RESULTS: A total of 121 variants were identified in APOB, of which four are novel variants missense (p.Thr626Asn, p.Ile2750Thr, p.Gln2078Lys and p.Met4184Arg). After curating pathogenicity scores, variants were classified according to the ACMG criteria. Among them four as pathogenic or likely pathogenic (p.Pro2739Leu, p.His1923Arg, p.Pro994Leu and p.Pro877Leu), and 21 variants had uncertain significance. Additionally, 92 previously known variants with uncertain significance were classified as benign or likely benign. The results were submitted to Clinvar for actualization of pathogenicity. CONCLUSIONS: These results improve the molecular diagnosis associating APOB variants with the clinical phenotype of hypercholesterolemia.


Assuntos
DNA , Técnicas de Diagnóstico Molecular , Sequenciamento do Exoma , Hipercolesterolemia , Adaptação Fisiológica , Mutação de Sentido Incorreto
12.
Public Health ; 222: 66-74, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37523950

RESUMO

OBJECTIVE: To investigate the alignment of national health priorities with a country's burden of disease as measured by disability-adjusted life years (DALYs). METHODS: We identified priorities in national health plans and the 20 most burdensome conditions measured by DALYs from the 2017 Global Burden of Disease Study. We computed point-biserial correlations (rpb) between DALYs and being nominated as a health priority and the pooled proportion (95% confidence intervals [CIs]) of the 20 most burdensome conditions nominated as a priority across countries. RESULTS: We identified national health plans and official governmental websites in 145 countries. There was little to no correlation (rpb = 0.06, 95% CI: 0.02 to 0.09) between national DALY data and whether a condition was nominated as a health priority. The pooled proportion of the 20 most burdensome conditions nominated as priorities across countries was 46%. HIV/AIDS had the greatest number of nominations as a national health priority (62 countries) as well as the greatest match with the burden of disease (among the top 20 most burdensome conditions in 51 [82%] countries). Low back pain, headache disorders and congenital birth defects had the lowest proportion of nominations as health priorities in countries where they were in the top 20 most burdensome conditions (6%, 6% and 11%, respectively). CONCLUSION: Globally, there were low correlations between national health priorities and GBD estimates on disease burden. Failing to prioritise health priorities according to burden may mean that insufficient resources have been directed to improve health outcomes for people with those health conditions.


Assuntos
Pessoas com Deficiência , Expectativa de Vida , Humanos , Anos de Vida Ajustados por Qualidade de Vida , Carga Global da Doença , Prioridades em Saúde , Saúde Global , Efeitos Psicossociais da Doença , Fatores de Risco
13.
Med Oral Patol Oral Cir Bucal ; 28(4): e341-e346, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37330968

RESUMO

BACKGROUND: Amyloidosis is a disease characterized by the progressive deposition of abnormal proteins that can occur in any organ. In the oral cavity, the tongue is the most common affected site, usually causing macroglossia. Biopsy is essential for the diagnosis and the occurrence of its systemic form is mandatory to be investigated. This systematic review evaluated the existing information in the literature on Amyloidosis in the oral cavity to allow a more comprehensive and updated analysis of its clinicopathological characteristics, as well as to explore the main forms of treatment and prognostic factors. MATERIAL AND METHODS: Electronic searches were undertaken in five databases supplemented by manual scrutiny. RESULTS: A total of 111 studies were included with 158 individuals. CONCLUSIONS: The disease had a higher prevalence in women, the tongue was the most affected site, as well as the systemic form of the disease. The worst prognosis was for cases of systemic amyloidosis associated with multiple myeloma.


Assuntos
Amiloidose , Macroglossia , Mieloma Múltiplo , Doenças da Língua , Humanos , Feminino , Amiloidose/diagnóstico , Amiloidose/complicações , Amiloidose/patologia , Macroglossia/complicações , Macroglossia/diagnóstico , Doenças da Língua/patologia , Língua/patologia
14.
JDS Commun ; 4(2): 166-168, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36974206

RESUMO

A pregnancy loss or abortion can be assumed when a dairy cow that has been previously diagnosed pregnant shows signs of estrus. In herds using leg-based pedometers as a tool to detect cows in estrus, a sudden increase in walking activity (hereafter, activity peaks) relative to a certain threshold activity triggers an estrous alert that can be confused with a pregnancy loss. The objective of this study was to determine whether pregnant cows can show activity peaks as measured by pedometers. We used data from a dairy herd of 250 milking cows using pedometers as a means of measuring walking activity to detect cows in estrus. Two databases were used in this study, which included the walking activity of the entire herd recorded by the pedometers from January 1, 2018, to December 31, 2021 (database 1), and the calving dates, the insemination dates, the dates when a pregnancy diagnosis was declared pregnant, the dates when a pregnancy diagnosis was declared not pregnant or open, and the abortion dates (database 2). Activity peaks were identified within an experimental unit, which was defined as pregnant cows showing an insemination event followed by a confirmed pregnancy and subsequent calving. The activity peaks were identified using the peak searching algorithm that compares the step count on a given day with the step counts of its adjacent days. The candidate peaks were characterized for their magnitudes by the prominence metric. A chi-squared test was performed to test the specificity of the system. From the 4-yr database, 537 pregnancies or experimental units were identified, and 77 pregnancies showed 1 or more peaks, which means that 14.4% of the pregnancies showed activity peaks. Within the pregnancies showing peaks (n = 77), the median equaled 1 peak/pregnancy, the average equaled 1.53 peaks/pregnancy, and the maximum equaled 13 peaks/pregnancy. In conclusion, activity peaks can be observed for pregnant cows using pedometers. These peaks could generate false estrous alerts during the pregnancy period when using pedometers, and these false alerts should not be interpreted as pregnancy losses.

15.
Trop Anim Health Prod ; 55(2): 71, 2023 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-36757607

RESUMO

Our study aimed to evaluate the frame size as a genetic selection criterion as well as the association of scores with carcass characteristics measured via ultrasound to the genetic improvement of carcass quality in Nellore cattle. The variance components were estimated using the restricted maximum likelihood method for the thoracic perimeter (TP), frame size score (FRAME), yearling weight (YW), visual scores of body structure (BS), muscularity (MUSC), and precocity (PREC). The carcass traits included loin eye area (REA), backfat thickness (BF), rump fat (FR), and intramuscular fat (IF). The estimated heritabilities ranged from moderate to high. The FRAME showed a positive genetic correlation with YW (0.82 ± 0.07), TP (0.58 ± 0.09), and BS score (0.62 ± 0.07), but it had a negative correlation with the MUSC and PREC visual scores (- 0.34 ± 0.09 and - 0.50 ± 0.08, respectively). The genetic correlation between FRAME and REA was positive (0.26 ± 0.09). However, FRAME presented a correlation close to zero with BF, RF, and IF. TP had a positive genetic correlation with body size traits such as YW (0.76 ± 0.05) and BS score (0.55 ± 0.08) and with muscularity traits such as REA (0.44 ± 0.01). Frame size has the potential to be used as a parameter in the selection of precocious beef cattle, but a study of its use is necessary to determine the ideal biotype for each production system.


Assuntos
Tamanho Corporal , Animais , Bovinos/genética , Fenótipo , Ultrassonografia
16.
J S Afr Vet Assoc ; 93(2): 70-75, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35934901

RESUMO

Reproduction is one of the most important factors determining successful cattle farming systems. Management practices, such as nutritional supplementation, can influence the reproductive performance of cattle. The objective of this literature review is to determine the potential value of injectable trace mineral administration on fresh and cryopreserved semen quality of bulls. A search of keywords related to the topic was performed on published articles and textbooks. The search was narrowed to the 40 most relevant references. Several studies have demonstrated a positive association between trace mineral supplementation and bull semen quality. Moderate amounts of reactive oxygen species (ROS) play an important role in normal spermatogenesis, but oxidative stress (OS), as experienced with adverse environmental conditions or disease, can contribute to idiopathic male infertility by negatively impacting spermatogenesis. Trace minerals such as selenium, copper, zinc, and manganese have been demonstrated to have antioxidant effects in mammals. Due to the complexity of oral ingested trace mineral bioavailability, injectable trace mineral supplementation prior to physiological periods with known deficiencies or increased requirement can benefit the animal. The potential benefits of injectable trace mineral supplementation to minimise oxidative damage to spermatogenesis in breeding bulls need further investigation. Positive results from such studies can lead to the implementation of injectable trace mineral supplementation strategies prior to the breeding season to minimise the detrimental effects of OS and can improve semen quality.


Assuntos
Preservação do Sêmen , Oligoelementos , Bovinos , Masculino , Animais , Oligoelementos/farmacologia , Preservação do Sêmen/veterinária , Análise do Sêmen/veterinária , Zinco/farmacologia , Suplementos Nutricionais , Estresse Oxidativo , Minerais , Mamíferos
18.
Braz J Biol ; 84: e260884, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35703638

RESUMO

Fluctuating asymmetry, defined as random differences between the two sides of a symmetrical structure, has been often related to development stress in both plants and animals. In plants, leaf fluctuating asymmetry has been related to stresses such as pollution and fire and may also be related to leaf growth and herbivory rates. We assessed whether leaf fluctuating asymmetry is related to plant and leaf size in Miconia albicans (Sw.) Triana (Melastomataceae), a common multi-stem Neotropical shrub, in a Brazilian savanna area. We collected 15 leaves from each of 70 individuals, and measured fluctuating asymmetry as the difference in area between the right and left sides of the leaves using the central vein as reference. To avoid spurious results due to measurement error, the division along the central vein was performed independently by three researchers. We also measured the basal area and height of each stem of the plant individuals. We used linear models to assess the relations between leaf fluctuating asymmetry, plant size and leaf size. No consistent relations were observed between leaf fluctuating asymmetry and plant size, as the analyses performed on the fluctuating asymmetry values obtained by the different researchers showed different results. However, relative fluctuating asymmetry values, obtained by dividing the fluctuating asymmetry by the total leaf area, tended to be smaller in larger leaves. It thus appears that, in the study species, fluctuating asymmetry is related to the developmental conditions faced by the individual leaves and not by the plant as a whole.


Assuntos
Incêndios , Melastomataceae , Animais , Herbivoria , Folhas de Planta , Plantas
19.
Sci Rep ; 12(1): 2617, 2022 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-35173223

RESUMO

Quantum wells formed by layers of HgTe between Hg[Formula: see text]Cd[Formula: see text]Te barriers lead to two-dimensional (2D) topological insulators, as predicted by the BHZ model. Here, we theoretically and experimentally investigate the characteristics of triple HgTe quantum wells. We describe such heterostructure with a three dimensional [Formula: see text] Kane model, and use its eigenstates to derive an effective 2D Hamiltonian for the system. From these we obtain a phase diagram as a function of the well and barrier widths and we identify the different topological phases composed by zero, one, two, and three sets of edge states hybridized along the quantum wells. The phase transitions are characterized by a change of the spin Chern numbers and their corresponding band inversions. Complementary, transport measurements are experimentally investigated on a sample close to the transition line between the phases with one and two sets of edges states. Accordingly, for this sample we predict a gapless spectrum with low energy bulk conduction subbands given by one parabolic and one Dirac subband, and with edge states immersed in the bulk valence subbands. Consequently, we show that under these conditions, local and non-local transport measurements are inconclusive to characterize a sole edge state conductivity due to bulk conductivity. On the other hand, Shubnikov-de Haas (SdH) oscillations show an excellent agreement with our theory. Particularly, we show that the measured SdH oscillation frequencies agrees with our model and show clear signatures of the coexistence of a parabolic and Dirac subbands.

20.
Cancer Genet ; 262-263: 16-22, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34974289

RESUMO

Intrachromosomal amplification of chromosome 21 (iAMP21) occurs in ∼2% of B-cell acute lymphoblastic leukemia (ALL) and is considered to confer a poor prognosis. The relapse risk is associated with therapy intensity, suggesting that other somatic mutations may influence iAMP21-ALL prognosis. This abnormality is characterized by multiple copies of the RUNX1 gene in chromosome 21 and appears to arise through multiple breakage-fusion bridge cycles and chromothripsis. Rob(15;21) or a ring chromosome 21 have been associated with an increased risk for iAMP21-ALL, suggesting that constitutional genetic abnormalities may also drive leukemogenesis. Here we describe homozygous deletion of the SH2B3 gene, chromothripsis of chromosome 21, and a non-Robertsonian somatic t(15;21)(q25.3;q22.1) with NTRK3 gene rearrangement in an adolescent with iAMP21-B-ALL. Molecular cytogenetic studies detected iAMP21 with aCGH analysis revealing further genomic imbalances. The RT-qPCR analysis detected elevated expression levels of RUNX1 (68-fold) and reduced expression of CDK6 (0.057-fold). Studies with constitutive cells collected from mouth swabs showed that SH2B3 biallelic deletion was a somatic alteration occurring during clonal evolution. The identification of novel secondary genetic changes was valuable to discuss sporadic iAMP21 leukemogenic mechanisms. For the first time, we show a t(15;21)(q25.3;q22.1) with NTRK3 rearrangement in an adolescent with iAMP21-ALL.


Assuntos
Linfoma de Burkitt , Cromotripsia , Leucemia-Linfoma Linfoblástico de Células Precursoras , Cromossomos em Anel , Adolescente , Linfoma de Burkitt/genética , Cromossomos Humanos Par 21/genética , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Homozigoto , Humanos , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Células Precursoras de Linfócitos B , Deleção de Sequência , Translocação Genética
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