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1.
Polymers (Basel) ; 16(8)2024 Apr 11.
Article in English | MEDLINE | ID: mdl-38674981

ABSTRACT

Polymeric blends are employed in the production of filaments for additive manufacturing to balance mechanical and processability properties. The mechanical and thermal properties of polymeric filaments made of poly (lactic acid) (PLA), polyhydroxyalkanoates (PHA), and its blend (PLA-PHA) are investigated herein and correlated to their measured structural and physicochemical properties. PLA exhibits the highest stiffness and tensile strength, but lower toughness. The mechanical properties of the PLA-PHA blend were similar to those of PLA, but with a significantly higher toughness. Despite the lower mechanical properties of neat PHA, incorporating a small amount (12 wt.%) of PHA into PLA significantly enhances toughness (approximately 50%) compared to pure PLA. The synergistic effect is attributed to the spherulitic morphology of blended PHA in PLA, promoting interactions between the amorphous regions of both polymers. Thermal stability is notably improved in the PLA-PHA blend, as determined by thermogravimetric analysis. The blend also exhibits lower cold crystallization and glass transition temperatures as compared to PLA, which is beneficial for additive manufacturing. Following additive manufacturing, X-ray photoelectron spectroscopic showed that the three filaments present an increase in C-C and C=O bonds associated with the loss of C-O bonds. The thermal process induces a slight increase in crystallinity in PHA due to chain reorganization. The study provides insights into the thermal and structural changes occurring during the melting process of additive manufacturing.

2.
Int J Mol Sci ; 24(8)2023 Apr 18.
Article in English | MEDLINE | ID: mdl-37108589

ABSTRACT

Given their tumor-specific and stage-specific gene expression, long non-coding RNAs (lncRNAs) have demonstrated to be potential molecular biomarkers for diagnosis, prognosis, and treatment response. Particularly, the lncRNAs DSCAM-AS1 and GATA3-AS1 serve as examples of this because of their high subtype-specific expression profile in luminal B-like breast cancer. This makes them candidates to use as molecular biomarkers in clinical practice. However, lncRNA studies in breast cancer are limited in sample size and are restricted to the determination of their biological function, which represents an obstacle for its inclusion as molecular biomarkers of clinical utility. Nevertheless, due to their expression specificity among diseases, such as cancer, and their stability in body fluids, lncRNAs are promising molecular biomarkers that could improve the reliability, sensitivity, and specificity of molecular techniques used in clinical diagnosis. The development of lncRNA-based diagnostics and lncRNA-based therapeutics will be useful in routine medical practice to improve patient clinical management and quality of life.


Subject(s)
Breast Neoplasms , RNA, Long Noncoding , Humans , Female , Breast Neoplasms/diagnosis , Breast Neoplasms/genetics , Breast Neoplasms/metabolism , RNA, Long Noncoding/genetics , RNA, Long Noncoding/metabolism , Quality of Life , Reproducibility of Results , Biomarkers , Biomarkers, Tumor/genetics , Gene Expression Regulation, Neoplastic
3.
Braz. j. biol ; 83: 1-9, 2023. map, ilus, tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1468908

ABSTRACT

Isla Arena is located in the coordinate 20° 70´ N - 90° 45´ W, from Campeche, Mexico. In these estuaries, the ocean mixes with fresh water, and ecosystems are concentrated where petenes and pink flamingos proliferate. Crustaceans and mollusks abound in the sea. Despite its enormous marine wealth, there are no studies carried out on which halophilic microorganisms are present in these waters. In this work, the diversity and structure of the microbial community was investigated through a metagenomics approach and corroborated for sequencing of 16S rRNA genes. It was found that the phylum Fimicutes predominates with more than 50%, in almost the same proportion of the class Bacilli and with almost 41% of relative abundance of the order Bacillales. The sequencing results showed that one of the samples presented a high percentage of similarity (99.75%) using the Nucleotide BLAST program with a peculiar microorganism: Bacillus subtilis. This microorganism is one of the best characterized bacteria among the gram-positive ones. Our results demonstrate that B. subtilis can be an efficient source of proteases, lipases and cellulases, from halophilic microbial communities located in poorly explored areas.


Isla Arena está localizada na coordenada 20°70’N - 90°45’W, de Campeche, México. Nesses estuários, o oceano se mistura com a água doce e os ecossistemas se concentram onde proliferam petenos e flamingos rosa. Crustáceos e moluscos abundam no mar. Apesar de sua enorme riqueza marinha, não há estudos realizados sobre a presença de microrganismos halofílicos nessas águas. Neste trabalho, a diversidade e estrutura da comunidade microbiana foram investigadas através de uma abordagem metagenômica e corroboradas para o sequenciamento de genes 16S rRNA. Verificou-se que o filo Fimicutes predomina com mais de 50%, quase na mesma proporção da classe Bacilli e com quase 41% de abundância relativa da ordem Bacillales. Os resultados do sequenciamento mostraram que uma das amostras apresentou alto percentual de similaridade (99,75%) pelo programa Nucleotide BLAST com um microrganismo peculiar: Bacillus subtilis. Nossos resultados demonstram que B. subtilis pode ser uma fonte eficiente de proteases, lipases e celulases, provenientes de comunidades microbianas halofílicas localizadas em áreas pouco exploradas.


Subject(s)
Animals , Bacillales/isolation & purification , Bacillus subtilis/growth & development , Ecosystem , Microbiota/genetics , /analysis
4.
Braz. j. biol ; 832023.
Article in English | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469124

ABSTRACT

Abstract Isla Arena is located in the coordinate 20° 70´ N - 90° 45´ W, from Campeche, Mexico. In these estuaries, the ocean mixes with fresh water, and ecosystems are concentrated where petenes and pink flamingos proliferate. Crustaceans and mollusks abound in the sea. Despite its enormous marine wealth, there are no studies carried out on which halophilic microorganisms are present in these waters. In this work, the diversity and structure of the microbial community was investigated through a metagenomics approach and corroborated for sequencing of 16S rRNA genes. It was found that the phylum Fimicutes predominates with more than 50%, in almost the same proportion of the class Bacilli and with almost 41% of relative abundance of the order Bacillales. The sequencing results showed that one of the samples presented a high percentage of similarity (99.75%) using the Nucleotide BLAST program with a peculiar microorganism: Bacillus subtilis. This microorganism is one of the best characterized bacteria among the gram-positive ones. Our results demonstrate that B. subtilis can be an efficient source of proteases, lipases and cellulases, from halophilic microbial communities located in poorly explored areas.


Resumo Isla Arena está localizada na coordenada 20°70N - 90°45W, de Campeche, México. Nesses estuários, o oceano se mistura com a água doce e os ecossistemas se concentram onde proliferam petenos e flamingos rosa. Crustáceos e moluscos abundam no mar. Apesar de sua enorme riqueza marinha, não há estudos realizados sobre a presença de microrganismos halofílicos nessas águas. Neste trabalho, a diversidade e estrutura da comunidade microbiana foram investigadas através de uma abordagem metagenômica e corroboradas para o sequenciamento de genes 16S rRNA. Verificou-se que o filo Fimicutes predomina com mais de 50%, quase na mesma proporção da classe Bacilli e com quase 41% de abundância relativa da ordem Bacillales. Os resultados do sequenciamento mostraram que uma das amostras apresentou alto percentual de similaridade (99,75%) pelo programa Nucleotide BLAST com um microrganismo peculiar: Bacillus subtilis. Nossos resultados demonstram que B. subtilis pode ser uma fonte eficiente de proteases, lipases e celulases, provenientes de comunidades microbianas halofílicas localizadas em áreas pouco exploradas.

5.
Braz. J. Biol. ; 83: 1-9, 2023. mapas, ilus, tab, graf
Article in English | VETINDEX | ID: vti-765485

ABSTRACT

Isla Arena is located in the coordinate 20° 70´ N - 90° 45´ W, from Campeche, Mexico. In these estuaries, the ocean mixes with fresh water, and ecosystems are concentrated where petenes and pink flamingos proliferate. Crustaceans and mollusks abound in the sea. Despite its enormous marine wealth, there are no studies carried out on which halophilic microorganisms are present in these waters. In this work, the diversity and structure of the microbial community was investigated through a metagenomics approach and corroborated for sequencing of 16S rRNA genes. It was found that the phylum Fimicutes predominates with more than 50%, in almost the same proportion of the class Bacilli and with almost 41% of relative abundance of the order Bacillales. The sequencing results showed that one of the samples presented a high percentage of similarity (99.75%) using the Nucleotide BLAST program with a peculiar microorganism: Bacillus subtilis. This microorganism is one of the best characterized bacteria among the gram-positive ones. Our results demonstrate that B. subtilis can be an efficient source of proteases, lipases and cellulases, from halophilic microbial communities located in poorly explored areas.(AU)


Isla Arena está localizada na coordenada 20°70N - 90°45W, de Campeche, México. Nesses estuários, o oceano se mistura com a água doce e os ecossistemas se concentram onde proliferam petenos e flamingos rosa. Crustáceos e moluscos abundam no mar. Apesar de sua enorme riqueza marinha, não há estudos realizados sobre a presença de microrganismos halofílicos nessas águas. Neste trabalho, a diversidade e estrutura da comunidade microbiana foram investigadas através de uma abordagem metagenômica e corroboradas para o sequenciamento de genes 16S rRNA. Verificou-se que o filo Fimicutes predomina com mais de 50%, quase na mesma proporção da classe Bacilli e com quase 41% de abundância relativa da ordem Bacillales. Os resultados do sequenciamento mostraram que uma das amostras apresentou alto percentual de similaridade (99,75%) pelo programa Nucleotide BLAST com um microrganismo peculiar: Bacillus subtilis. Nossos resultados demonstram que B. subtilis pode ser uma fonte eficiente de proteases, lipases e celulases, provenientes de comunidades microbianas halofílicas localizadas em áreas pouco exploradas.(AU)


Subject(s)
Animals , Ecosystem , Microbiota/genetics , RNA, Ribosomal, 16S/analysis , Bacillus subtilis/growth & development , Bacillales/isolation & purification
6.
Braz. j. biol ; 83: e246038, 2023. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1339397

ABSTRACT

Abstract Isla Arena is located in the coordinate 20° 70´ N - 90° 45´ W, from Campeche, Mexico. In these estuaries, the ocean mixes with fresh water, and ecosystems are concentrated where petenes and pink flamingos proliferate. Crustaceans and mollusks abound in the sea. Despite its enormous marine wealth, there are no studies carried out on which halophilic microorganisms are present in these waters. In this work, the diversity and structure of the microbial community was investigated through a metagenomics approach and corroborated for sequencing of 16S rRNA genes. It was found that the phylum Fimicutes predominates with more than 50%, in almost the same proportion of the class Bacilli and with almost 41% of relative abundance of the order Bacillales. The sequencing results showed that one of the samples presented a high percentage of similarity (99.75%) using the Nucleotide BLAST program with a peculiar microorganism: Bacillus subtilis. This microorganism is one of the best characterized bacteria among the gram-positive ones. Our results demonstrate that B. subtilis can be an efficient source of proteases, lipases and cellulases, from halophilic microbial communities located in poorly explored areas.


Resumo Isla Arena está localizada na coordenada 20°70'N - 90°45'W, de Campeche, México. Nesses estuários, o oceano se mistura com a água doce e os ecossistemas se concentram onde proliferam petenos e flamingos rosa. Crustáceos e moluscos abundam no mar. Apesar de sua enorme riqueza marinha, não há estudos realizados sobre a presença de microrganismos halofílicos nessas águas. Neste trabalho, a diversidade e estrutura da comunidade microbiana foram investigadas através de uma abordagem metagenômica e corroboradas para o sequenciamento de genes 16S rRNA. Verificou-se que o filo Fimicutes predomina com mais de 50%, quase na mesma proporção da classe Bacilli e com quase 41% de abundância relativa da ordem Bacillales. Os resultados do sequenciamento mostraram que uma das amostras apresentou alto percentual de similaridade (99,75%) pelo programa Nucleotide BLAST com um microrganismo peculiar: Bacillus subtilis. Nossos resultados demonstram que B. subtilis pode ser uma fonte eficiente de proteases, lipases e celulases, provenientes de comunidades microbianas halofílicas localizadas em áreas pouco exploradas.


Subject(s)
Archaea , Microbiota , Phylogeny , Bacteria/genetics , RNA, Ribosomal, 16S/genetics , Mexico
8.
J Parasit Dis ; 46(1): 37-46, 2022 Mar.
Article in English | MEDLINE | ID: mdl-35299905

ABSTRACT

The domiciliation of Triatoma maculata and Rhodnius prolixus and the entomological risk indicators for the transmission of Trypanosoma cruzi, an etiological agent of Chagas Disease-CD, were studied in rural villages of Anzoátegui state, Venezuela. Nightly home visits were made for 4 months/year, for 2 years, to search for and capture triatomines in human settlements. For six of the evaluated villages, 16.4% (11/67) of houses were found with triatomine infestation; obtaining 151 triatomines in all their ontogenetic stages, of which 54.3% (82/151) corresponded to T. maculata and 45.7% (69/151) to R. prolixus. In 7.5% of the evaluated houses, both species were presented in sympatry. Entomological indicators of transmission risk were higher for T. maculata in relation to R. prolixus. Inoculation of fecal flagellates of triatomines produced 2.92 × 105 flagellates/mL of blood in mean and 100% mortality in the murine model. Molecular tests (satellite DNA, kDNA and DTUs studies) demonstrated the presence of T. cruzi, all compatible with TcI. The food source determined by IESPA, revealed that R. prolixus showed less eclecticism in relation to T. maculata in the use of blood sources. This could be an indicator of an older domiciliation with low dispersion between ecotopes. The sympatry of T. maculata and R. prolixus had been recorded in natural niches, but for the first time it is recorded inside the houses in rural villages of the Anzoátegui state. Human dwellings can constitute an adequate niche, with available food sources for both triatomines species and with the risk of establishing AT/CD as zoonosis or zooanthroponosis.

9.
Braz J Biol ; 83: e246038, 2021.
Article in English | MEDLINE | ID: mdl-34495150

ABSTRACT

Isla Arena is located in the coordinate 20° 70´ N - 90° 45´ W, from Campeche, Mexico. In these estuaries, the ocean mixes with fresh water, and ecosystems are concentrated where petenes and pink flamingos proliferate. Crustaceans and mollusks abound in the sea. Despite its enormous marine wealth, there are no studies carried out on which halophilic microorganisms are present in these waters. In this work, the diversity and structure of the microbial community was investigated through a metagenomics approach and corroborated for sequencing of 16S rRNA genes. It was found that the phylum Fimicutes predominates with more than 50%, in almost the same proportion of the class Bacilli and with almost 41% of relative abundance of the order Bacillales. The sequencing results showed that one of the samples presented a high percentage of similarity (99.75%) using the Nucleotide BLAST program with a peculiar microorganism: Bacillus subtilis. This microorganism is one of the best characterized bacteria among the gram-positive ones. Our results demonstrate that B. subtilis can be an efficient source of proteases, lipases and cellulases, from halophilic microbial communities located in poorly explored areas.


Subject(s)
Archaea , Microbiota , Bacteria/genetics , Mexico , Phylogeny , RNA, Ribosomal, 16S/genetics
10.
Rev. med. vet. zoot ; 68(2): 105-123, mayo-ago. 2021. tab, graf
Article in English | LILACS, COLNAL | ID: biblio-1352097

ABSTRACT

ABSTRACT Serological controls for diseases of viral origin in animal production systems and the identification of factors associated with infections are decisive elements to establish prevention and control measures. The aim of this study was to establish the serological status for Bovine Viral Diarrhea (BVD) and Enzootic Bovine Leukemia (EBL) viruses in Blanco Orejinegro (BON) cattle from Colombia, and to identify the factors associated with seropositivity. A cross-sectional study was conducted with a total of 498 animals of all age groups and physiological states of the BON breed were selected, belonging to 14 herds located in 6 states of Colombia, in which a survey with 27 questions was conducted. By means of the chi-square test, possible factors associated with seropositivity against the 2 viruses were identified. A sample of 4 ml of blood was taken from each animal to extract plasma and make indirect Elisa tests to detect antibodies against both pathogens. General seropositivity of 27,1% was obtained for EBL, finding as factors associated with seropositivity the inadequate disposition of placental tissues after delivery of the cows and the non-performance of serological tests on new animals entering the herd. For BVD, seropositivity obtained was 50,6%, and the factors associated with seropositivity identified were having had a history of the disease in the herd, and using semen from bulls that are not known to be free for the infection. We suggest establishing control measures considering the factors associated with each viral infection to limit their expansion in the BON cattle production systems of Colombia.


RESUMO Os controles sorológicos para doenças de origem viral nos sistemas de produção animal e a identificação de fatores associados à infecção são elementos decisivos para estabelecer medidas de prevenção e controle. O objetivo deste estudo foi estabelecer o status sorológico dos vírus da Diarréia Viral Bovina (BVD) e da Leucemia Bovina Enzoótica (EBL) em bovinos Blanco Orejinegro (BON) da Colômbia e identificar os fatores associados à soropositividade. Foram selecionados 498 animais de todas as faixas etárias e estados fisiológicos da raça BON, de 14 rebanhos localizados em seis regiões da Colômbia, nos quais foi realizada uma pesquisa para identificar possíveis fatores associados à soropositividade contra os dois vírus. Foi retirada uma amostra de 4 ml de sangue de cada animal para extrair plasma e fazer testes ELISA indiretos para detectar anticorpos contra os dois patógenos. Obteve-se soropositividade geral de 27,1% para EBL, encontrando como fatores associados à soropositividade a disposição inadequada dos tecidos placentários após o parto das vacas e a não realização de testes sorológicos em novos animais que entraram no rebanho. Para a BVD, a soropositividade obtida foi de 50,6%, e os fatores associados à soropositividade identificados foram: histórico de doença no rebanho e uso de sêmen de touros que não são reconhecidos como livres da infecção. Sugerimos o estabelecimento de medidas de controle considerando os fatores associados a cada infecção viral para limitar sua expansão nos sistemas de produção de gado BON da Colômbia.


Subject(s)
Virus Diseases , Cattle , Enzyme-Linked Immunosorbent Assay , Serologic Tests , Leukemia , Cross-Sectional Studies , Enzootic Bovine Leukosis , Diarrhea Viruses, Bovine Viral , Infections , Semen , Diarrhea , Livestock
11.
Biodemography Soc Biol ; 66(2): 156-171, 2021.
Article in English | MEDLINE | ID: mdl-34182852

ABSTRACT

Studies of the current Chilean population performed using classical genetic markers have established that the Chilean population originated primarily from the admixture of European people, particularly Spaniards, and Amerindians. A socioeconomic-ethno-genetic cline was established soon after the conquest. Spaniards born in Spain or Chile occupied the highest Socioeconomic Strata, while Amerindians belonged to the lowest. The intermediate strata consisted of people with different degrees of ethnic admixture; the larger the European admixture, the higher the Socioeconomic Level. The present study of molecular genomic markers sought to calculate the percentage of Amerindian admixture and revealed a finer distribution of this cline, as well as differences between two Amerindian groups: Aymara and Mapuche. The use of two socioeconomic classifications - Class and Socioeconomic Level - reveals important differences. Furthermore, Self-reported Ethnicity (self-assignment to an ethnic group) and Self-reported Ancestry (self-recognition of Amerindian ancestors) show variations and differing relationships between socioeconomic classifications and genomic Amerindian Admixture. These data constitute a valuable input for the formulation of public healthcare policy and show that the notions of Ethnicity, Socioeconomic Strata and Class should always be a consideration in policy development.


Subject(s)
Ethnicity , Genomics , Chile , Gene Frequency , Genetic Markers , Humans , Indians, South American/genetics , Spain
12.
Climacteric ; 24(6): 577-586, 2021 12.
Article in English | MEDLINE | ID: mdl-34008476

ABSTRACT

Osteoporosis is a highly prevalent systemic skeletal disorder leading to decreased bone strength and increased susceptibility to fragility fracture. The global burden of osteoporosis negatively impacts health systems around the world, and the estimation of millions of individuals at high risk for fracture in 2010 will double by the year 2040. There are many techniques to evaluate bone mineral density, but the preferred method in clinical practice is dual-energy X-ray absorptiometry (DXA). This method, despite offering multiple advantages, can lead us to a wrong diagnosis if we do not take into account certain clinical and technical considerations. The objective of this review is to analyze the different aspects that we must consider when, as clinicians, we have to evaluate a densitometric report. These aspects are presented as technical factors influencing DXA results and patients' conditions limiting DXA interpretation.


Subject(s)
Absorptiometry, Photon , Fractures, Bone , Osteoporosis , Bone Density , Diagnostic Errors , Humans , Osteoporosis/diagnostic imaging
13.
Rev. med. vet. zoot ; 68(1): 66-74, ene.-abr. 2021. tab, graf
Article in Spanish | LILACS, COLNAL | ID: biblio-1352093

ABSTRACT

RESUMEN La enfermedad podal constituye uno de los síndromes más difíciles de controlar en la industria lechera. El presente estudio tuvo como objetivo cuantificar la prevalencia de enfermedad podal, evaluando su asociación con factores como raza, orden de parto y peso. Se trata de un estudio retrospectivo que utiliza los registros sanitarios y productivos de un hato lechero ubicado en el trópico alto de Colombia. Los componentes raciales presentes fueron Fl Holstein x Blanco Orejinegro, 3/4 Holstein 1/4 Blanco Orejinegro, 5/8 Holstein 3/8 Blanco Orejinegro y Holstein 100%. Se consideraron 6 órdenes de parto. La variable enfermedad podal presenta una distribución binomial. El efecto de los factores se verificó utilizando un modelo lineal generalizado, por medio de una regresión logística (PROC GENMOD SAS versión 9.4). En caso de existir diferencias significativas, se aplicó el procedimiento LSMEANS del SAS (versión 9.4) y un Odds Rattio entre los niveles que presentaron significancia. La prevalencia de enfermedad podal en el hato fue de 10,55%. Los factores de riesgo considerados fueron estadísticamente significativos: componente racial (p < 0,0009), orden parto (p < 0,0001) y peso medio de las vacas (p < 0,0001). Se observó un incremento en la prevalencia de la enfermedad asociado a la raza Holstein, orden de parto alto y bajo peso corporal. La prevalencia de enfermedad podal fue mayor en vacas Holstein puras y menor en vacas Holstein cruzadas con Blanco Orejinegro, debido a la resistencia por heterosis que la raza criolla aporta. El incremento del orden de parto al igual que el bajo peso se relacionan con una mayor prevalencia de esta enfermedad.


ABSTRACT Foot disease is one of the most difficult syndromes to control in the dairy industry. The goal of this study was to quantify the prevalence of foot disease, evaluating its association with factors such as race, calving order and weight. This is a retrospective study using the health and production records of a dairy herd located in the high tropics of Colombia. The racial components present were F1 Holstein x Blanco Orejinegro, 3/4 Holstein 1/4 Blanco Orejinegro, 5/8 Holstein 3/8 Blanco Orejinegro, Holstein 100%. 6 delivery orders were considered. The variable foot disease presents a binomial distribution. The effect of the factors was verified using a generalized linear model, by means of a logistic regression (PROC GENMOD SAS version 9.4). In the event of significant differences, the SAS LSMEANS procedure (version 9.4) and an Odds Ratio were applied between the levels that presented significance. The prevalence of foot disease in the herd was 10,55%. The risk factors considered were statistically significant: racial component (p < 0,0009), calving order (p < 0,0001) and average weight of the cows (p < 0,0001). An increase in the prevalence of the disease was observed associated with the Holstein breed, high calving order and low body weight. The prevalence of foot disease was higher in pure Holstein cows and lower in Holstein cows crossed with Blanco Orejinegro due to the resistance due to heterosis that the creole breed contributes. The increase in the delivery order as well as the low weight are related to a higher prevalence of this disease.


Subject(s)
Animals , Cattle , Syndrome , Body Weight , Cattle , Prevalence , Tropical Ecosystem , Dairying , Racial Groups , Locomotion , Binomial Distribution , Disease , Retrospective Studies , Risk Factors
14.
Polymers (Basel) ; 13(4)2021 Feb 23.
Article in English | MEDLINE | ID: mdl-33672211

ABSTRACT

The aim of this work is to investigate the effect of the applied voltage on the morphological and mechanical properties of electrospun polycaprolactone (PCL) scaffolds for potential use in tissue engineering. The morphology of the scaffolds was characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM), and the BET techniques for measuring the surface area and pore volume. Stress-strain curves from tensile tests were obtained for estimating the mechanical properties. Additional studies for detecting changes in the chemical structure of the electrospun PCL scaffolds by Fourier transform infrared were performed, while contact angle and X-ray diffraction analysis were realized for determining the wettability and crystallinity, respectively. The SEM, AFM and BET results demonstrate that the electrospun PCL fibers exhibit morphological changes with the applied voltage. By increasing the applied voltage (10 to 25 kV) a significate influence was observed on the fiber diameter, surface roughness, and pore volume. In addition, tensile strength, elongation, and elastic modulus increase with the applied voltage, the crystalline structure of the fibers remains constant, and the surface area and wetting of the scaffolds diminish. The morphological and mechanical properties show a clear correlation with the applied voltage and can be of great relevance for tissue engineering.

15.
Acta Virol ; 64(4): 451-456, 2020.
Article in English | MEDLINE | ID: mdl-33151739

ABSTRACT

Bovine leukemia virus (BLV) is a retrovirus that affects primarily milky cows. Animals serologically positive to BLV show a Th1 cytokine profile with a predominance of interferon gamma (IFN-γ). IFN-γ has antiviral activity through mechanisms such as resistance to infection, inhibition of viral replication and apoptosis. The objective of this work was to determine the transcription levels of IFN-γ and its relationship with proviral load and persistent lymphocytosis in a population of Holstein cows of the province of Antioquia, Colombia. IFN-γ transcription levels were evaluated by qPCR in 140 Holstein cows. A one-way analysis of variance and a Student's t test were used to evaluate the differences between the means. The amount of IFN-γ mRNA found in BLV-positive cows was lower than in BLV-negative cows. Moreover, in the group of infected cows a lower level of IFN-γ mRNA expression was found in BLV and persistent lymphocytosis cows (BLV+PL) compared with BLV and aleukemia cows (BLV+AL). The level of IFN-γ mRNA expression was lower in cows with high proviral load (HPL) compared to cows with low proviral load (LPL). BLV infection is related to abnormal expression of IFN-γ mRNA, although IFN-γ has antiviral activity, its expression is affected by high proviral load. Keywords: cytokine; immune system; leukemia; bovine leukemia virus.


Subject(s)
Enzootic Bovine Leukosis/immunology , Interferon-gamma/genetics , Lymphocytosis/veterinary , Viral Load , Animals , Cattle , Colombia , Enzootic Bovine Leukosis/genetics , Humans , Leukemia Virus, Bovine , Lymphocytosis/genetics , Proviruses , RNA, Messenger
16.
Int J Immunopathol Pharmacol ; 34: 2058738420907186, 2020.
Article in English | MEDLINE | ID: mdl-32138573

ABSTRACT

The goals of our study were to determine the possible association of interleukin (IL)-31 with Th17 cytokine profile in serum and to quantify retinoic acid-related orphan receptor C (RORC) mRNA expression in psoriatic arthritis (PsA) patients. This cross-sectional study was conducted in 50 patients with PsA and 30 control subjects (CS) matched by age and gender. The cytokine serum levels were quantified by magnetic bead-based assay using the Bio-Plex MAGPIX system, and RORC mRNA expression was determined by quantitative polymerase chain reaction (qPCR). As a result, significant differences in IL-31 were observed between study groups (77.23 pg/mL in PsA vs 64.4 pg/mL in CS, P < 0.001) and Th17 cytokine profile serum levels (IL-17A: 6.36 pg/mL in PsA vs 2.97 pg/mL in CS, P = 0.02; IL-17F: 44.15 pg/mL in PsA vs 23.36 pg/mL in PsA, P = 0.01; IL-17E: 3.03 pg/mL in PsA vs 0.82 pg/mL in CS, P < 0.001; IL-21: 36.45 pg/mL in PsA vs 12.44 pg/mL in CS, P = 0.02); however, significant differences were not observed for IL-23 (31.2 pg/mL in PsA vs 53.26 pg/mL in CS, P = 0.58). Furthermore, positive correlations between IL-31 and Th17 cytokine profile serum levels were found (IL-17A: rs = 0.64, P < 0.001; IL-17F: rs = 0.73, P < 0.001; IL-17E: rs = 0.70, P < 0.001; IL-21: rs = 0.54, P = 0.002; IL-23: rs = 0.5, P < 0.01). Regarding RORC gene expression, the PsA group showed an increase of 6.85-fold compared to the CS group. We did not find any association between the serum levels of cytokines and RORC gene expression. In conclusion, in PsA, there are increased serum levels of IL-31, IL-17A, IL-17F, IL-17E, and IL-21, but not IL-23. Moreover, there was a positive correlation of IL-31 with the Th17 cytokine profile and a high RORC gene expression. Altogether, these findings suggest a proinflammatory contribution of IL-31 in close association with the Th17 cytokine profile in PsA.


Subject(s)
Arthritis, Psoriatic/metabolism , Arthritis, Psoriatic/pathology , Cytokines/metabolism , Inflammation/metabolism , Inflammation/pathology , Interleukins/metabolism , Th17 Cells/metabolism , Adult , Aged , Cross-Sectional Studies , Cytokines/blood , Female , Humans , Interleukin-17/genetics , Interleukin-17/metabolism , Interleukins/genetics , Male , Middle Aged , Nuclear Receptor Subfamily 1, Group F, Member 3/genetics , Nuclear Receptor Subfamily 1, Group F, Member 3/metabolism
17.
Polymers (Basel) ; 12(1)2020 Jan 15.
Article in English | MEDLINE | ID: mdl-31952108

ABSTRACT

In this research, damage in bone cements that were prepared with core-shell nanoparticles was monitored during four-point bending tests through an analysis of acoustic emission (AE) signals. The core-shell structure consisted of poly(butyl acrylate) (PBA) as rubbery core and methyl methacrylate/styrene copolymer (P(MMA-co-St)) as a glassy shell. Furthermore, different core-shell ratios 20/80, 30/70, 40/60, and 50/50 were prepared and incorporated into the solid phase of the bone cement formulation at 5, 10, and 15 wt %, respectively. The incorporation of a rubbery phase into the bone cement formulation decreased the bending strength and bending modulus. The AE technique revealed that the nanoparticles play an important role on the fracture mechanism of the bone cement, since a higher amount of AE signals (higher amplitude and energy) were obtained from bone cements that were prepared with the nanoparticles in comparison with those without nanoparticles (the reference bone cement). The SEM examination of the fracture surfaces revealed that all of the bone cement formulations exhibited stress whitening, which arises from the development of crazes before the crack propagation. Finally, the use of the AE technique and the fracture surface analysis by SEM enabled insight into the fracture mechanisms that are presented during four-point bending test of the bone cement containing nanoparticles.

18.
Acta Ortop Mex ; 34(6): 412-416, 2020.
Article in Spanish | MEDLINE | ID: mdl-34020522

ABSTRACT

Traumatic spondyloptosis is a serious injury usually caused by high-energy trauma; It consists of the anterior or posterior dislocation of 100% or more of the underlying vertebral body, which can become a total injury of the spinal cord, producing a neurological deficit; this type of injury represents stage 4 and 5 of Allen-Ferguson. Clinical case: A 50-year-old man who suffers a car accident, he receive frontal impact when he was a driver, colliding with the retaining wall, referred from another hospital to emergency room, managed with C7 hemicorpectomy, c7-t1 discectomy, spondylodesis with anterior plate (C6-T1), and posterior approach + Fascetectomies of C7-T1, facet joint screws C6 and transpedicular fixation of T1. Discussion: Subaxial cervical spondyloptosis is relatively rare clinical entity, a complete clinical examination is important in diagnosis, taking in considerations the injury mechanism. For treatment we have a multiple options, at this case anterior-posterior (360 degrees) treatment it was the better option for Us; however, must be personalized and consider the early rehabilitation of patient.


La espondiloptosis traumática es una lesión muy rara y grave generalmente causada por traumatismos de alta energía. Consiste en la dislocación anterior o posterior de 100% o más al cuerpo vertebral subyacente, lo que puede generar compresión y lesión total de la médula espinal, produciendo déficit neurológico; este tipo de lesión representa la etapa 4 y 5 de Allen. Caso clínico: Masculino de 50 años quien sufre accidente automovilístico al colisionar contra muro de contención, generándose lesión de tipo hiperextensión-compresión cervicotorácica, manejado con hemicorpectomía C7, discectomía C7-T1, espondilodesis con placa anterior (C6-C7, C7-T1), toma y aplicación de injerto, abordaje posterior + fascetectomías de C7 + fijación transfacetaria C6 y transpedicular de T1. Discusión: Encontramos que la estabilización temprana con pinza de Gardner más el abordaje anterior y posterior brindan adecuados resultados en cuanto a integridad sensitiva y motora del paciente así como una pronta rehabilitación.


Subject(s)
Joint Dislocations , Spinal Fusion , Spondylolisthesis , Bone Plates , Cervical Vertebrae/diagnostic imaging , Cervical Vertebrae/surgery , Humans , Male , Middle Aged , Spondylolisthesis/surgery
19.
Braz. j. biol ; Braz. j. biol;79(3): 505-509, July-Sept. 2019. tab, graf
Article in English | LILACS | ID: biblio-1001446

ABSTRACT

Abstract Salt water recirculation systems using automatic feeders are a new frontier for marine aquaculture. It is possible to decrease the vulnerability of the traditional fish farming in open systems and reduce wasteful feeding and discharge of effluents, as well as increase the economic returns. An experiment with common snook fingerings (4.31 ± 1.42 g and 8.4 ± 1.0 cm) was performed. Three feeding treatments were evaluated: six, twelve and eighteen feeding times per day. Each treatment had three replications. Among the three tested frequencies (fed 6, 12 and 18 times a day), the feeding frequency of 12 times per day (every two hours) showed the best values of the parameters evaluated for production performance. The final weight values, condition factor, specific growth rate and daily weight gain of the treatment 12 feeding times per day were all significantly higher than the lower and higher frequencies. Our results demonstrate that high feeding frequency is not synonymous of higher performance, but is extremely necessary to find out the best range for the target species. Besides, this relationship between feeding frequency and growth performance might change over weight range. Therefore, future studies should address higher weight ranges for comparison to our results.


Resumo Sistemas de recirculação de água salgada utilizando alimentadores automáticos são uma nova fronteira para a aquicultura marinha. Possibilitam diminuir a vulnerabilidade dos cultivos em sistemas abertos e conferir redução de desperdício de ração e lançamento de efluentes, assim como elevar o retorno econômico. Foi realizado um experimento com juvenis de Robalo-flecha (4,31 ± 1,42 g e 8,4 ± 1,0 cm). Três frequências alimentares foram avaliadas: alimentação seis vezes ao dia; doze vezes ao dia, e; dezoito vezes ao dia. Cada tratamento teve três repetições. Dentre as três frequências avaliadas a frequência alimentar de 12 vezes ao dia foi a que apresentou os melhores valores para os parâmetros zootécnicos avaliados. Os valores obtidos de peso final, fator de condição, taxa de crescimento específico e ganho de peso diário foram todos maiores para a frequência de 12 vezes ao dia do que os obtidos para as frequências maior e menor. Nossos resultados demonstram que elevadas frequências alimentares não são sinônimo de melhor desempenho produtivo, mas é extremamente importante conhecer a frequência ideal para a espécie a ser cultivada. Além disto, a relação entre frequência alimentar e crescimento pode mudar de acordo com a faixa de peso dos indivíduos. Desta forma, é extremamente importante que trabalhos futuros avaliem as frequências aqui estudadas para comparar os resultados em indivíduos maiores.


Subject(s)
Animals , Perciformes/growth & development , Aquaculture/methods , Diet/veterinary , Random Allocation , Animal Feed/analysis
20.
Phys Rev E ; 99(2-1): 022108, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30934340

ABSTRACT

The statistical mechanics of a cloud of particles interacting via their gravitational potentials encounters some issues when the Boltzmann-Gibbs statistics is applied. In this work, we consider the alternative statistical framework of Tsallis and analyze the statistical and thermodynamical implications for a self-gravitating gas, obtaining analytical and convergent expressions for the equation of state and specific heat in the ensembles of constant temperature and constant energy. Although our results are comparable in both ensembles, it turns out that only in the ensemble of constant temperature do the thermodynamic quantities depend explicitly on the Tsallis parameter, indicating that the question of ensemble equivalence for Tsallis statistics must be further reviewed.

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