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1.
Rev Esp Cir Ortop Traumatol ; 68(3): T271-T279, 2024.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-38621437

RESUMO

INTRODUCTION: Bone as a material varies its composition and mechanical properties throughout life. Although these variations are better understood in adulthood, there is little experimental information on the variation of these properties in early stages of development. The objective of this study is to analyze the mechanical behavior and chemical properties of cortical bone tissue from two animal species in these earliest stages. MATERIAL AND METHODOLOGY: Twenty specimens of cortical bone were manufactured from bovine and ovine species that were in different stages of development (feeding exclusively on breast milk, in the transition period to feed or pasture, and young animals but on a solid food diet). The specimens were subjected to tensile tests, recorded with a high-speed camera to obtain deformation maps. Measurements of the tensile force until the specimen broke were also carried out. A fractographic study was carried out with a scanning electron microscope to analyze the fracture surface and an analysis of the amount of calcium in each of the specimens using X-ray dispersion spectroscopy. RESULTS: A statistically significant and positive correlation was found between the elastic modulus of the specimens and their calcium content. A trend towards more rigid behavior with age was observed. CONCLUSIONS: Young bone tissue tends to stiffen with age as the calcium content increases with an increase in elastic modulus.

3.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-38043739

RESUMO

INTRODUCTION: Bone as a material varies its composition and mechanical properties throughout life. Although these variations are better understood in adulthood, there is little experimental information on the variation of these properties in early stages of development. The objective of this study is to analyze the mechanical behavior and chemical properties of cortical bone tissue from two animal species in these earliest stages. MATERIAL AND METHODOLOGY: Twenty specimens of cortical bone were manufactured from bovine and ovine species that were in different stages of development (feeding exclusively on breast milk, in the transition period to feed or pasture, and young animals but on a solid food diet). The specimens were subjected to tensile tests, recorded with a high-speed camera to obtain deformation maps. Measurements of the tensile force until the specimen broke were also carried out. A fractographic study was carried out with a scanning electron microscope to analyze the fracture surface and an analysis of the amount of calcium in each of the specimens using X-ray dispersion spectroscopy. RESULTS: A statistically significant and positive correlation was found between the elastic modulus of the specimens and their calcium content. A trend towards more rigid behavior with age was observed. CONCLUSIONS: Young bone tissue tends to stiffen with age as the calcium content increases with an increase in elastic modulus.

4.
J Investig Allergol Clin Immunol ; 33(2): 95-101, 2023 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-36069440

RESUMO

Suspected or confirmed antibiotic allergy is a frequent clinical circumstance that influences antimicrobial prescription and often leads to the avoidable use of less efficacious and/or more toxic or costly drugs than first-line antimicrobials. Optimizing antimicrobial therapy in patients with antibiotic allergy labels has become one of the priorities of antimicrobial stewardship programs in several countries. These guidelines aim to make recommendations for the systematic approach to patients with suspected or confirmed antibiotic allergy based on current evidence. An expert panel (11 members of various scientific societies) formulated questions about the management of patients with suspected or confirmed antibiotic allergy. A systematic literature review was performed by a medical librarian. The questions were distributed among panel members who selected the most relevant references, summarized the evidence, and formulated graded recommendations when possible. The answers to all the questions were finally reviewed by all panel members. A systematic approach to patients with suspected or confirmed antibiotic allergy was recommended to improve antibiotic selection and, consequently, clinical outcomes. A clinically oriented, 3-category risk-stratification strategy was recommended for patients with suspected antibiotic allergy. Complementary assessments should consider both clinical risk category and preferred antibiotic agent. Empirical therapy recommendations for the most relevant clinical syndromes in patients with suspected or confirmed ß-lactam allergy were formulated, as were recommendations on the implementation and monitoring of the impact of the guidelines. Antimicrobial stewardship programs and allergists should design and implement activities that facilitate the most appropriate use of antibiotics in these patients.


Assuntos
Doenças Transmissíveis , Hipersensibilidade a Drogas , Hipersensibilidade , Serviço de Farmácia Hospitalar , Humanos , Unidades de Cuidados Coronarianos , Antibacterianos/efeitos adversos , Doenças Transmissíveis/tratamento farmacológico , Hipersensibilidade a Drogas/terapia , Hipersensibilidade a Drogas/tratamento farmacológico , Hipersensibilidade/tratamento farmacológico
5.
Philos Trans A Math Phys Eng Sci ; 380(2223): 20200386, 2022 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-35341308

RESUMO

Three methods for non-adiabatic dynamics are compared to highlight their capabilities. Multi-configurational time-dependent Hartree is a full grid-based solution to the time-dependent Schrödinger equation, variational multi-configurational Gaussian (vMCG) uses a less flexible but unrestricted Gaussian wavepacket basis, and trajectory surface hopping (TSH) replaces the nuclear wavepacket with a swarm of classical trajectories. Calculations with all methods using a model Hamiltonian were performed. The vMCG and TSH were also then run in a direct dynamics mode, with the potential energy surfaces calculated on-the-fly using quantum chemistry calculations. All dynamics calculations used the Quantics package, with the TSH calculations using a new interface to a surface hopping code. A novel approach to calculate adiabatic populations from grid-based quantum dynamics using a time-dependent discrete variable representation is presented, allowing a proper comparison of methods. This article is part of the theme issue 'Chemistry without the Born-Oppenheimer approximation'.

6.
Rev Clin Esp ; 222(6): 354-358, 2022.
Artigo em Espanhol | MEDLINE | ID: mdl-33495655

RESUMO

Background: A high incidence of pulmonary embolism has been described during the coronavirus pandemic. Methods: This work is a single-center retrospective study which reviewed computed tomography pulmonary angiograms ordered due to suspected pulmonary embolism during two periods: from March 1, 2020 to May 31, 2020 (pandemic) and during the same interval in 2019 (control). Results: Twenty-two pulmonary embolism were diagnosed during the control period and 99 in the pandemic, 74 of which were associated with COVID-19. Of all patients hospitalized with COVID-19, 5.3% had a pulmonary embolism, with a delay between the two diagnoses of 9.1 ± 8.4 days. During the pandemic, patients with pulmonary embolism had fewer predisposing conditions (previous pulmonary embolism 5.1 vs. 18.2%, p = .05; previous surgery 2 vs. 35.4%, p = .0001; deep vein thrombosis 11.1 vs. 45.5%, p = .0001); peripheral pulmonary embolisms were the most frequent (73.5 vs. 50%, p = . 029). Conclusions: There is an increased risk of having a pulmonary embolism during the SARS-CoV-2 pandemic, which affects patients with a different clinical profile and more often causes distal pulmonary embolisms.

8.
Rev Clin Esp (Barc) ; 222(6): 354-358, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34147421

RESUMO

BACKGROUND: A high incidence of pulmonary embolism has been described during the coronavirus pandemic. METHODS: This work is a single-center retrospective study which reviewed computed tomography pulmonary angiograms ordered due to suspected pulmonary embolism during two periods: from March 1, 2020 to May 31, 2020 (pandemic) and during the same interval in 2019 (control). RESULTS: Twenty-two pulmonary embolisms were diagnosed during the control period and 99 in the pandemic, 74 of which were associated with COVID-19. Of all patients hospitalized with COVID-19, 5.3% had a pulmonary embolism, with a delay between the two diagnoses of 9.1 ± 8.4 days. During the pandemic, patients with pulmonary embolism had fewer predisposing conditions (previous pulmonary embolism 5.1 vs. 18.2%, p = .05; previous surgery 2 vs. 35.4%, p = .0001; deep vein thrombosis 11.1 vs. 45.5%, p = .0001); peripheral pulmonary embolisms were the most frequent (73.5 vs. 50%, p = . 029). CONCLUSIONS: There is an increased risk of having a pulmonary embolism during the SARS-CoV-2 pandemic, which affects patients with a different clinical profile and more often causes distal pulmonary embolisms.


Assuntos
COVID-19 , Embolia Pulmonar , COVID-19/complicações , Humanos , Pandemias , Embolia Pulmonar/diagnóstico por imagem , Embolia Pulmonar/epidemiologia , Embolia Pulmonar/etiologia , Estudos Retrospectivos , SARS-CoV-2
9.
Glob Environ Change ; 69: 102281, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34471331

RESUMO

Intensive agriculture and densely populated areas represent major sources of nutrient pollution for European inland and coastal waters, altering the aquatic ecosystems and affecting their capacity to provide ecosystem services and support economic activities. Ambitious water policies are in place in the European Union (EU) for protecting and restoring aquatic ecosystems under the Water Framework Directive and the Marine Strategy Framework Directive. This research quantified the current pressures of point and diffuse nitrogen and phosphorus emissions to European fresh and coastal waters (2005-2012), and analysed the effects of three policy scenarios of nutrient reduction: 1) the application of measures currently planned in the Rural Development Programmes and under the Urban Waste Water Treatment Directive (UWWTD); 2) the full implementation of the UWWTD and the absence of derogations in the Nitrates Directive; 3) high reduction of nutrient, using best technologies in wastewaters treatment and optimal fertilisation in agriculture. The results of the study show that for the period 2005-2012, the nitrogen load to European seas was 3.3-4.1 TgN/y and the phosphorus load was 0.26-0.30 TgP/y. Policy measures supporting technological improvements (third scenario) could decrease the nutrient export to the seas up to 14% for nitrogen and 20% for phosphorus, improving the ecological status of rivers and lakes, but widening the nutrient imbalance in coastal ecosystems (i.e. increasing nitrogen availability with respect to phosphorus), affecting eutrophication. Further nutrient reductions could be possible by a combination of measures especially in the agricultural sector. However, without tackling current agricultural production and consumption system, the reduction might not be sufficient for achieving the goals of EU water policy in some regions. The study analysed the expected changes and the source contribution in different European regional seas, and highlights the advantages of addressing the land-sea dynamics, checking the coherence of measures taken under different policies.

10.
Vet Microbiol ; 258: 109121, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34020174

RESUMO

This study compares the utility of a commercially available multiplex q-PCR assay for serotyping A1, A2, and A6 M. haemolytica serotypes with indirect hemagglutination, for determining the relative distribution of M. haemolytica capsular types associated with respiratory disorders in cattle, sheep, and goats. For the 129 isolates analyzed, both q-PCR and IHA assays exhibited nearly complete agreement for capsular types A1 (k = 0.965) and A2 (k = 0.888) and substantial agreement for A6 (k = 0.801). Despite the overall good performance of the commercial q-PCR, its effectiveness differed between the host origin of the isolates. The serotype was identified by q-PCR in 83.3 % of cattle, 77.8 % of goat, and 53.8 % of sheep isolates. Combining the results of both methods, A1 was the most prevalent in cattle and sheep (55.6 % and 22.25 %, respectively) but was not detected in goats, A2 was the most prevalent in goats (61.1 %) and the second most prevalent in cattle (16.7 %) and sheep (20.5 %). The prevalence of A6 was 7.4 %, 5.1 %, and 16.7 % in cattle, sheep, and goats, respectively. Other capsular types determined exclusively by IHA were A16 in cattle, A9 in goats, and A7, A8, A9, and A13 in sheep. Capsular type diversity was greater in sheep (H = 0.601) than in cattle (H = 0.408) and goat (H = 0.330) isolates. The commercial multiplex q-PCR is a valuable tool, alternative to IHA, for identifying isolates of capsular types A1, A2, and A6, the most frequent serotypes of M. haemolytica associated with respiratory disease in ruminants. However, when testing sheep isolates it should be complemented with immunological assays due to the wider range of serotypes implicated.


Assuntos
Cápsulas Bacterianas/classificação , Doenças dos Bovinos/microbiologia , Doenças das Cabras/microbiologia , Mannheimia haemolytica/classificação , Doenças dos Ovinos/microbiologia , Animais , Bovinos , Doenças dos Bovinos/epidemiologia , Doenças das Cabras/epidemiologia , Cabras , Reação em Cadeia da Polimerase Multiplex/métodos , Reação em Cadeia da Polimerase Multiplex/veterinária , Reação em Cadeia da Polimerase em Tempo Real/métodos , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Ovinos , Doenças dos Ovinos/epidemiologia , Espanha/epidemiologia
11.
J Chem Phys ; 154(14): 144303, 2021 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-33858147

RESUMO

In spite of being spin-forbidden, some enzymes are capable of catalyzing the incorporation of O2(Σg-3) to organic substrates without needing any cofactor. It has been established that the process followed by these enzymes starts with the deprotonation of the substrate forming an enolate. In a second stage, the peroxidation of the enolate formation occurs, a process in which the system changes its spin multiplicity from a triplet state to a singlet state. In this article, we study the addition of O2 to enolates using state-of-the-art multi-reference and single-reference methods. Our results confirm that intersystem crossing is promoted by stabilization of the singlet state along the reaction path. When multi-reference methods are used, large active spaces are required, and in this situation, semistochastic heat-bath configuration interaction emerges as a powerful method to study these multi-configurational systems and is in good agreement with PNO-LCCSD(T) when the system is well-represented by a single-configuration.

12.
Anim Genet ; 52(3): 333-341, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33621396

RESUMO

Insulin deficiency diabetes (IDD) in dogs is an endocrine disease similar to human type 1 diabetes. There are breeds more commonly affected, such as Yorkshire Terrier and Samoyed, suggesting an underlying genetic component. However, the genetic basis for canine diabetes mellitus (DM) is not fully established. We conducted both whole-genome scans for selection signatures and GWASs to compare the genomes of 136 dogs belonging to 29 breeds previously described at low or high risk for developing DM. Candidate variants were tested in dogs with a diagnosis of IDD and controls attending the Complutense Veterinary Teaching Hospital. The only genomic region under selection (CFA8:72 700 000-74 600 000; CanFam3.1) retrieved by our analyses is included in the immunoglobulin heavy chain gene cluster, which has already been related to human human type 1 diabetes susceptibility. This region contains two non-synonymous variants, rs852072969 and rs851728071, showing significant associations with high or low risk for IDD, respectively. The first variant, rs852072969, alters a protein poorly characterised in the dog. In contrast, rs851728071 was predicted to block the synthesis of an immunoglobulin variable (V) domain in breeds at low risk for DM. Although a large and diverse V gene repertoire is thought to offer a fitness advantage, we suggest that rs851728071 prevents the formation of an auto-reactive immunoglobulin V domain probably involved in the pathophysiology of IDD and, thus, decreases the risk for the disease. These results should be interpreted with caution until the functional roles of the proposed variants have been proved in larger studies.


Assuntos
Diabetes Mellitus/veterinária , Doenças do Cão/genética , Cães/genética , Genes de Cadeia Pesada de Imunoglobulina , Família Multigênica , Animais , Cruzamento , Diabetes Mellitus/genética , Predisposição Genética para Doença , Genoma , Estudo de Associação Genômica Ampla/veterinária , Polimorfismo de Nucleotídeo Único
13.
J Investig Allergol Clin Immunol ; 31(3): 196-211, 2021 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-33502318

RESUMO

Chronic rhinosinusitis (CRS) is an inflammatory disease of the nose and paranasal sinuses that is often associated with nasal polyposis (CRSwNP) in the most severe cases. As in other complex diseases, genetic factors are thought to play an important role in the risk and development of the disease. Environment may also modulate the epigenetic signature in affected patients. In the present systematic review, we aimed to compile all published data on genetic and epigenetic variations in CRSwNP since 2000. We found 104 articles, 24 of which were related to epigenetic studies. We identified more than 150 genetic variants in 99 genes involved in the pathogenesis of nasal polyposis. These were clustered into 8 main networks, linking genes involved in inflammation and immune response (eg, MHC), cytokine genes (eg, TNF), leukotriene metabolism, and the extracellular matrix. A total of 89 miRNAs were also identified; these are associated mainly with biological functions such as the cell cycle, inflammation, and the immune response. We propose a potential relationship between genes and the miRNAs identified that may open new lines of investigation. An in-depth knowledge of gene variants and epigenetic traits could help us to design more tailored treatment for patients with CRSwNP.


Assuntos
MicroRNAs/genética , Pólipos Nasais/genética , Rinite/genética , Sinusite/genética , Doença Crônica , Epigênese Genética , Redes Reguladoras de Genes , Humanos , Imunidade/genética , Polimorfismo Genético
15.
Sci Adv ; 6(50)2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33298437

RESUMO

Serine 2 phosphorylation (S2P) within the CTD of RNA polymerase II is considered a Cdk9/Cdk12-dependent mark required for 3'-end processing. However, the relevance of CTD S2P in metazoan development is unknown. We show that cdk-12 lesions or a full-length CTD S2A substitution results in an identical phenotype in Caenorhabditis elegans Embryogenesis occurs in the complete absence of S2P, but the hatched larvae arrest development, mimicking the diapause induced when hatching occurs in the absence of food. Genome-wide analyses indicate that when CTD S2P is inhibited, only a subset of growth-related genes is not properly expressed. These genes correspond to SL2 trans-spliced mRNAs located in position 2 and over within operons. We show that CDK-12 is required for maximal occupancy of cleavage stimulatory factor necessary for SL2 trans-splicing. We propose that CTD S2P functions as a gene-specific signaling mark ensuring the nutritional control of the C. elegans developmental program.


Assuntos
Caenorhabditis elegans , Diapausa , Animais , Caenorhabditis elegans/genética , Diapausa/genética , Desenvolvimento Embrionário/genética , Estudo de Associação Genômica Ampla , Fosforilação , RNA Polimerase II/genética , Serina/genética
16.
J Investig Allergol Clin Immunol ; 30(2): 117-126, 2020 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-31062691

RESUMO

BACKGROUND AND OBJECTIVE: Prostaglandin D2 receptors are acquiring a relevant role as potential therapeutic targets in allergy. PTGDR has been described as a candidate gene in allergic disease, although functional studies on this gene are lacking. Objective: The objective of this case-control study was to investigate the potential role of PTGDR in allergy. METHODS: The study population comprised 195 allergic patients and 112 healthy controls. The PTGDR promoter polymorphisms -1289G>A, -1122T>C, -881C>T, -834C>T, -613C>T, -549T>C, -441C>T, -197T>C, and -95G>T were amplified by polymerase chain reaction (PCR) and sequenced. PTGDR expression levels were analyzed using quantitative PCR and normalized to GAPDH and TBP mRNA levels. All procedures were performed following the Minimum Information for Publication of Quantitative Real-Time PCR Experiment guidelines. RESULTS: PTGDR expression levels were significantly higher in allergic patients than in controls (P<.001). Receiver operating characteristic analysis for expression of PTGDR showed a sensitivity of 81.4% compared with 67% for IgE levels. In addition, differences in the genotypic distribution of the polymorphisms -1289G>A and -1122T>C were found in allergic patients (P=.009). CONCLUSIONS: The results indicate that PTGDR overexpression is associated with allergy. The polymorphisms -1289G>A and -1122T>C partly explain the variation in expression we observed. PTGDR expression could have a potential role as a biomarker and pharmacogenetic factor in allergy.


Assuntos
Hipersensibilidade/genética , Receptores Imunológicos/genética , Receptores de Prostaglandina/genética , Adulto , Idoso , Biomarcadores , Feminino , Genótipo , Humanos , Hipersensibilidade/sangue , Imunoglobulina E/sangue , Masculino , Pessoa de Meia-Idade , Regiões Promotoras Genéticas , RNA Mensageiro , Adulto Jovem
19.
Anim Genet ; 50(3): 275-278, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30968968

RESUMO

Four loci seem responsible for the dilution of the basic coat colours in horse: Dun (D), Silver Dapple (Z), Champagne (CH) and Cream (C). Apart from the current phenotypes ascribed to these loci, pearl has been described as yet another diluted coat colour in this species. To date, this coat colour seems to segregate only in the Iberian breeds Purebred Spanish horse and Lusitano and has also been described in breeds of Iberian origin, such as Quarter Horses and Paint Horse, where it is referred to as the 'Barlink Factor'. This phenotype segregates in an autosomal recessive manner and resembles some of the coat colours produced by the champagne CHCH and cream CCr alleles, sometimes being difficult to distinguish among them. The interaction between compound heterozygous for the pearl Cprl and cream CCr alleles makes SLC45A2 the most plausible candidate gene for the pearl phenotype in horses. Our results provide documented evidence for the missense variation in exon 4 [SLC45A2:c.985G>A; SLC45A2:p.(Ala329Thr)] as the causative mutation for the pearl coat colour. In addition, it is most likely involved as well in the cremello, perlino and smoky cream like phenotypes associated with the compound CCr and Cprl heterozygous genotypes (known as cream pearl in the Purebred Spanish horse breed). The characterization of the pearl mutation allows breeders to identify carriers of the Cprl allele and to select this specific coat colour according to personal preferences, market demands or studbook requirements as well as to verify segregation within particular pedigrees.


Assuntos
Cor de Cabelo , Cavalos/genética , Proteínas de Membrana Transportadoras/genética , Mutação de Sentido Incorreto , Animais , Éxons , Polimorfismo de Nucleotídeo Único
20.
Rev Clin Esp (Barc) ; 219(4): 184-188, 2019 May.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-30651196

RESUMO

BACKGROUND AND OBJECTIVES: The ω-5 gliadin (ω5G) is considered the main allergen in wheat-dependent exercise-induced anaphylaxis (WDEIA). These patients experience anaphylactic reactions after consuming wheat and performing physical exercise. The aim of our study was to describe the main characteristics of 12 patients with this diagnosis. MATERIAL AND METHODS: A descriptive, retrospective study was conducted by reviewing the medical records of 12 patients diagnosed with ω-5G hypersensitivity. RESULTS: The patients' mean age was 37 years, with 50% men and 50% women. Most of the patients had a history of similar unexamined episodes. The latency period varied from immediate to 150min. The most common symptoms were urticaria (83%), bronchospasms (58%), angio-oedema (42%), hypotension (25%) and gastrointestinal symptoms (16%). The most often involved cofactor was physical exercise. The allergy study was conducted with prick tests and total and specific IgE readings. CONCLUSIONS: WDEIA is a relatively rare but potentially severe food allergy. Understanding this allergy is therefore important for a correct diagnosis.

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