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1.
Braz J Biol ; 84: e278601, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38422291

RESUMO

The use of biomass for energy production constitutes a promising strategy that warrants the search for new sources of biomass. Elephant grass has been gaining notoriety due to its high dry matter yield and rapid growth. The present study was carried out to quantify the genetic divergence of nine elephant grass half-sib families in order to identify genotypes with greater genetic divergence and productive potential for hybridization, using the hierarchical clustering methodology based on principal components. Half-sib families were generated using genotypes from the Active Germplasm Bank of Elephant Grass. The experiment was laid out in a randomized-block design with nine half-sib families, three replicates, and eight plants per plot. A total of 216 genotypes of elephant grass were evaluated. Principal component (PC), biplot, and hierarchical clustering analyses for diversity estimation were conducted using R software. The first two PCs of biplot analysis accounted for 64% of the cumulative variation. Dry matter yield was the most important trait for genotype discrimination (0.89), followed by plant height (0.67) and stem diameter (0.61) in PC1. In this analysis, the distances between accessions were considered and there were no family links, which indicates the existence of wide variability within the evaluated families, since genotypes belonging to the same family were not grouped together, but rather distributed into different groups. Crosses between genotypes of group three and genotypes of groups one and two are recommended for the development of high-yielding genotypes when aiming at energy production.


Assuntos
Variação Genética , Hibridização Genética , Biomassa , Variação Genética/genética , Genótipo , Fenótipo , Distribuição Aleatória
2.
Braz J Biol ; 83: e278007, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38126483

RESUMO

Low density sugarcane plantation (LDSP) has been implemented by some sugarcane producers in Brazil, aiming to save seeds and operational costs. The study was carried out in the municipality of Areia, Paraíba, Brazil. Five planting densities were used, varying from 5 to 25 m-2 of buds arranged in randomized blocks, with four replications. Data were measured annually over three cultivation cycles (2017 to 2020), during which the field was fertilized with NPK and the harvests were carried out manually without prior burning. The lower planting density presents higher productivity only in the cane plant (101.03 t ha-1) due to the higher plant height (2.37 m) and the higher number of stalks (11 stalks m-2), suggesting that these variables are due to the greater availability of light, water and photosynthate. However, there is a drastic reduction in sugarcane yield for this lower population in the 2nd ratoon by up to 65.62%, which is correlated with number of stalks per meter. We demonstrate the agronomic viability of LDSP in the population of 10 buds m-2 in relation to conventional planting of sugarcane until the 2nd ratoon. Data are important for future studies to present additional considerations for other production factors, such as the effects of mechanized harvesting and the management of nutrients and water, assessing the sustainability of this large-scale planting system.


Assuntos
Saccharum , Agricultura , Sementes , Água , Brasil
3.
Eur Arch Paediatr Dent ; 24(3): 369-378, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36928835

RESUMO

PURPOSE: To evaluate the CBCT referrals in paediatric patients over a 24-month period. METHODS: A retrospective study was conducted in two radiological centers in Campinas, Brazil. Patients were divided into three age groups: G1: age under 10 years, G2: age between 10 and 12 years, and G3: age over 12 years. The following data were collected: patients' age and sex, localisation, reasons for referral and dental specialty responsible for the request of CBCT exams. RESULTS: Data from 367 patients were assessed. CBCT was used more frequently in the Group 3 (58.9%). There was significant association between the region of the exam and age group (P < 0.05), with a higher percentage of exams in the maxilla for the age over 12 years (35.6%) than that of up to 10 years (50.9%) and between 10 and 12 years (51.1%). Alterations were observed in 79.3% of the exams and 47.4% showed impacted teeth with significant association with the increase in age group (P < 0.05). Of the total number of exams, (55.3%) were requested in Orthodontics followed by Oral Surgery (30.0%) and Paediatric Dentistry (9.5%). CONCLUSIONS: It can be concluded that CBCT exams were indicated frequently for the age over 12 years. The presence of impacted teeth represented the main reason for referrals and Orthodontics was the dental specialty that indicated CBCT with higher frequency.


Assuntos
Tomografia Computadorizada de Feixe Cônico Espiral , Dente Impactado , Humanos , Criança , Lactente , Estudos Retrospectivos , Brasil , Tomografia Computadorizada de Feixe Cônico , Encaminhamento e Consulta
4.
Cryo Letters ; 44(1): 47-56, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36629841

RESUMO

BACKGROUND: Skin cryobanks represent important tools for the conservation of the maximum genetic representation of a population, especially those with a certain degree of threat to extinction, such as the ocelot. A relevant step towards the proper establishment of these banks is the definition of adequate cryopreservation techniques for the conservation of the skin. OBJECTIVE: We evaluated the effects of two different techniques [direct vitrification in cryovials (DVC) and solid-surface vitrification (SSV)] for the preservation of ear skin derived from ocelot. MATERIALS & METHODS: For both techniques, we vitrified the ear skin using Dulbeccos modified Eagles medium with 3.0 M dimethyl sulfoxide, 0.25 M sucrose, and 10% fetal bovine serum. Non-cryopreserved tissues were used as control (control group). All tissues were analyzed for their morphometric characteristics by conventional histology and morphological / functional analysis by cell ability during the culture. RESULTS: While tissues cryopreserved by DVC showed similar values for dermis thickness and number of perinuclear halos to the control, tissues cryopreserved by SSV showed similarities to the control regarding the number of melanocytes, percentage of collagen fibers, and numbers of viable cells by apoptosis analysis. Additionally, none of the vitrification techniques affected stratum corneum thickness, number of keratinocytes, tissue proliferative activity, cell viability, or metabolism. CONCLUSION: Both vitrification techniques (DVC and SSV) can be used for the conservation of ocelot skin; however, SSV guarantees a higher cellular quality after in vitro tissue culture in most of the parameters evaluated, such as viability, metabolism, and apoptosis analysis. doi.org/10.54680/fr23110110412.


Assuntos
Criopreservação , Vitrificação , Criopreservação/métodos , Crioprotetores/farmacologia , Dimetil Sulfóxido , Sacarose/farmacologia
5.
Materials (Basel) ; 15(22)2022 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-36431729

RESUMO

MgF2-coated screws made of a Mg-2Y-1Mn-1Zn alloy, called NOVAMag® fixation screws (biotrics bioimplants AG), were tested in vitro for potential applications as biodegradable implants, and showed a controlled corrosion rate compared to non-coated screws. While previous studies regarding coated Mg-alloys have been carried out on flat sample surfaces, the present work focused on functional materials and final biomedical products. The substrates under study had a complex 3D geometry and a nearly cylindrical-shaped shaft. The corrosion rate of the samples was investigated using an electrochemical setup, especially adjusted to evaluate these types of samples, and thus, helped to improve an already patented coating process. A MgF2/MgO coating in the µm-range was characterized for the first time using complementary techniques. The coated screws revealed a smoother surface than the non-coated ones. Although the cross-section analysis revealed some fissures in the coating structure, the electrochemical studies using Hanks' salt solution demonstrated the effective role of MgF2 in retarding the alloy degradation during the initial stages of corrosion up to 24 h. The values of polarization resistance (Rp) of the coated samples extrapolated from the Nyquist plots were significantly higher than those of the non-coated samples, and impedance increased significantly over time. After 1200 s exposure, the Rp values were 1323 ± 144 Ω.cm2 for the coated samples and 1036 ± 198 Ω.cm2 for the non-coated samples, thus confirming a significant decrease in the degradation rate due to the MgF2 layer. The corrosion rates varied from 0.49 mm/y, at the beginning of the experiment, to 0.26 mm/y after 1200 s, and decreased further to 0.01 mm/y after 24 h. These results demonstrated the effectiveness of the applied MgF2 film in slowing down the corrosion of the bulk material, allowing the magnesium-alloy screws to be competitive as dental and orthopedic solutions for the biodegradable implants market.

6.
Philos Trans R Soc Lond B Biol Sci ; 377(1849): 20200497, 2022 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-35249394

RESUMO

Palaeoecological records suggest that humans have been in the Andes since at least 14 000 years ago. Early human impacts on Andean ecosystems included an increase in fire activity and the extinction of the Pleistocene megafauna. These changes in Andean ecosystems coincided with rapid climate change as species were migrating upslope in response to deglacial warming. Microrefugia probably played a vital role in the speed and genetic composition of that migration. The period from ca 14 500 to 12 500 years ago was when novel combinations of plant species appeared to form no-analogue assemblages in the Andes. By 12 000 years ago most areas in what are today the Andean grasslands were being burned and modified by human activity. As the vegetation of these highland settings has been modified by human activity for the entirety of the Holocene, they should be regarded as long-term manufactutred landscapes. The sharp tree lines separating Andean forests from grasslands that we see today were probably also created by repeated burning and owe their position more to human-induced fire than climatic constraints. In areas that were readly penetrated by humans on the forested slopes of the Andes, substantial modification and settlement had occurred by the mid-Holocene. In hard-to-reach areas, however, the amount of human modification may always have been minimal, and these slopes can be considered as being close to natural in their vegetation. This article is part of the theme issue 'Tropical forests in the deep human past'.


Assuntos
Ecossistema , Incêndios , Florestas , Atividades Humanas , Humanos , Árvores
8.
J Hosp Infect ; 123: 43-51, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35189301

RESUMO

BACKGROUND: Central venous catheter-related bloodstream infection (CRBSI) is a huge public health concern with considerable impact on mortality and health costs. AIM: A three-year observational study enrolling three tertiary hospitals located in Lisbon, Portugal, was designed to identify the major aetiological agents of CRBSI, their ability to colonize central venous catheters and their antimicrobial resistance profiles. METHODS: Aetiological agents of CRBSI were identified by Vitek 2. Whole-genome sequencing was used to confirm CRBSI by the most prevalent aetiological agents and characterize their resistome. Central venous catheter colonization (namely by biofilm assembly) was monitored by scanning electron microscopy. FINDINGS: Staphylococci were the most prevalent causative agent (36/58, 62.0%), with S. aureus and coagulase-negative S. epidermidis accounting for 24.1% and 36.2% of CRBSIs, respectively. Fifty-nine of 72 staphylococci isolates were meticillin resistant. Comparative genomic analysis of central venous catheters/haemoculture pairs of isolates revealed genomic matches for 35 of 36 pairs and a good correlation between antibiotic susceptibility phenotype and the presence of antimicrobial resistance genetic determinants. Biofilms were present on 48.6% of the central venous catheters; nevertheless, no statistically significant association was established between biofilm assembly and CRBSI, and the presence/absence of ica operon and agr groups did not correlate with biofilm phenotypes, highlighting the need for further studies to elucidate biofilms' role on this healthcare-associated infection. CONCLUSION: Whole-genome sequencing was shown to be a valuable tool to confirm CRBSI. Although more than 42.3% of the central venous catheters were colonized by staphylococci, no statistically significant association was found between CRBSI and biofilms.


Assuntos
Bacteriemia , Infecções Relacionadas a Cateter , Cateteres Venosos Centrais , Bacteriemia/epidemiologia , Infecções Relacionadas a Cateter/complicações , Infecções Relacionadas a Cateter/epidemiologia , Cateteres Venosos Centrais/efeitos adversos , Resistência a Múltiplos Medicamentos , Humanos , Staphylococcus , Staphylococcus aureus
9.
Braz. j. biol ; 82: 1-6, 2022. map, tab, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1468418

RESUMO

The "piaussu", Megaleporinus macrocephalus is an anostomatid fish species native to the basin of the Paraguay River, in the Pantanal biome of western Brazil. However, this species has now been recorded in a number of other drainages, including those of the upper Paraná, Uruguay, Jacuí, Doce, Mucuri, and Paraíba do Sulrivers. This study presents two new records of the occurrence of M. macrocephalus, in the basins of the Itapecuru and Mearim rivers in the state of Maranhão, in the Brazilian Northeast. The piaussu is a large-bodied fish of commercial interest that is widely raised on fish farms, and its occurrence in the Itapecuru and Mearim rivers is likely the result of individuals escaping from fish tanks when they overflow during the rainy season. Morphological analyses and sequences of the Cytochrome Oxidase Subunit I (COI) gene confirmed the taxonomic identification of the specimens as M. macrocephalus. The COI sequences were 99.66% similar to those of M. macrocephalus deposited in the BOLDSystems database. These records extend the known distribution of M. macrocephalus to the basins of the Itapecuru and Mearim rivers in the Brazilian Northeast, highlighting a new case of introduction of exotic fish species into Brazilian river basins.


Megaleporinus macrocephalus é uma espécie de peixe anostomatídeo nativa da bacia do rio Paraguai, no bioma Pantanal do oeste do Brasil. No entanto, essa espécie já foi registrada em várias outras drenagens, incluindo as dos rios Alto Paraná, Uruguai, Jacuí, Doce, Mucuri e Paraíba do Sul. Este estudo apresenta dois novos registros da ocorrência de M. macrocephalus, nas bacias dos rios Itapecuru e Mearim, no estado do Maranhão, no nordeste brasileiro. O piaussu é um peixe de grande porte, de interesse comercial, amplamente criado em pisciculturas, e sua ocorrência nos rios Itapecuru e Mearim é provavelmente o resultado de indivíduos que escapam dos tanques quando transbordam durante a estação chuvosa. Análises morfológicas e sequências do gene da subunidade I do citocromo oxidase (COI) confirmaram a identificação taxonômica dos espécimes como M. macrocephalus. As sequências de COI foram 99,66% semelhantes às de M. macrocephalus depositadas no banco de dados BOLDSystems. Esses registros estendem a conhecida distribuição de M. macrocephalus às bacias dos rios Itapecuru e Mearim, no nordeste brasileiro, destacando um novo caso de introdução de espécies exóticas de peixes nas bacias hidrográficas brasileiras.


Assuntos
Animais , Peixes/anatomia & histologia , Peixes/genética
10.
Braz. j. biol ; 822022.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1468605

RESUMO

Abstract The piaussu, Megaleporinus macrocephalus is an anostomatid fish species native to the basin of the Paraguay River, in the Pantanal biome of western Brazil. However, this species has now been recorded in a number of other drainages, including those of the upper Paraná, Uruguay, Jacuí, Doce, Mucuri, and Paraíba do Sulrivers. This study presents two new records of the occurrence of M. macrocephalus, in the basins of the Itapecuru and Mearim rivers in the state of Maranhão, in the Brazilian Northeast. The piaussu is a large-bodied fish of commercial interest that is widely raised on fish farms, and its occurrence in the Itapecuru and Mearim rivers is likely the result of individuals escaping from fish tanks when they overflow during the rainy season. Morphological analyses and sequences of the Cytochrome Oxidase Subunit I (COI) gene confirmed the taxonomic identification of the specimens as M. macrocephalus. The COI sequences were 99.66% similar to those of M. macrocephalus deposited in the BOLDSystems database. These records extend the known distribution of M. macrocephalus to the basins of the Itapecuru and Mearim rivers in the Brazilian Northeast, highlighting a new case of introduction of exotic fish species into Brazilian river basins.


Resumo Megaleporinus macrocephalus é uma espécie de peixe anostomatídeo nativa da bacia do rio Paraguai, no bioma Pantanal do oeste do Brasil. No entanto, essa espécie já foi registrada em várias outras drenagens, incluindo as dos rios Alto Paraná, Uruguai, Jacuí, Doce, Mucuri e Paraíba do Sul. Este estudo apresenta dois novos registros da ocorrência de M. macrocephalus, nas bacias dos rios Itapecuru e Mearim, no estado do Maranhão, no nordeste brasileiro. O piaussu é um peixe de grande porte, de interesse comercial, amplamente criado em pisciculturas, e sua ocorrência nos rios Itapecuru e Mearim é provavelmente o resultado de indivíduos que escapam dos tanques quando transbordam durante a estação chuvosa. Análises morfológicas e sequências do gene da subunidade I do citocromo oxidase (COI) confirmaram a identificação taxonômica dos espécimes como M. macrocephalus. As sequências de COI foram 99,66% semelhantes às de M. macrocephalus depositadas no banco de dados BOLDSystems. Esses registros estendem a conhecida distribuição de M. macrocephalus às bacias dos rios Itapecuru e Mearim, no nordeste brasileiro, destacando um novo caso de introdução de espécies exóticas de peixes nas bacias hidrográficas brasileiras.

11.
Braz. j. biol ; 82: e232868, 2022. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1153458

RESUMO

The "piaussu", Megaleporinus macrocephalus is an anostomatid fish species native to the basin of the Paraguay River, in the Pantanal biome of western Brazil. However, this species has now been recorded in a number of other drainages, including those of the upper Paraná, Uruguay, Jacuí, Doce, Mucuri, and Paraíba do Sulrivers. This study presents two new records of the occurrence of M. macrocephalus, in the basins of the Itapecuru and Mearim rivers in the state of Maranhão, in the Brazilian Northeast. The piaussu is a large-bodied fish of commercial interest that is widely raised on fish farms, and its occurrence in the Itapecuru and Mearim rivers is likely the result of individuals escaping from fish tanks when they overflow during the rainy season. Morphological analyses and sequences of the Cytochrome Oxidase Subunit I (COI) gene confirmed the taxonomic identification of the specimens as M. macrocephalus. The COI sequences were 99.66% similar to those of M. macrocephalus deposited in the BOLDSystems database. These records extend the known distribution of M. macrocephalus to the basins of the Itapecuru and Mearim rivers in the Brazilian Northeast, highlighting a new case of introduction of exotic fish species into Brazilian river basins.


Megaleporinus macrocephalus é uma espécie de peixe anostomatídeo nativa da bacia do rio Paraguai, no bioma Pantanal do oeste do Brasil. No entanto, essa espécie já foi registrada em várias outras drenagens, incluindo as dos rios Alto Paraná, Uruguai, Jacuí, Doce, Mucuri e Paraíba do Sul. Este estudo apresenta dois novos registros da ocorrência de M. macrocephalus, nas bacias dos rios Itapecuru e Mearim, no estado do Maranhão, no nordeste brasileiro. O piaussu é um peixe de grande porte, de interesse comercial, amplamente criado em pisciculturas, e sua ocorrência nos rios Itapecuru e Mearim é provavelmente o resultado de indivíduos que escapam dos tanques quando transbordam durante a estação chuvosa. Análises morfológicas e sequências do gene da subunidade I do citocromo oxidase (COI) confirmaram a identificação taxonômica dos espécimes como M. macrocephalus. As sequências de COI foram 99,66% semelhantes às de M. macrocephalus depositadas no banco de dados BOLDSystems. Esses registros estendem a conhecida distribuição de M. macrocephalus às bacias dos rios Itapecuru e Mearim, no nordeste brasileiro, destacando um novo caso de introdução de espécies exóticas de peixes nas bacias hidrográficas brasileiras.


Assuntos
Humanos , Animais , Rios , Caraciformes/genética , Paraguai , Uruguai , Brasil
12.
Ultrason Sonochem ; 73: 105541, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33839530

RESUMO

Copper molybdate nanoplates were synthesized by a sonochemical process at room temperature, which we report as a simple and cost-effective route. Structural analysis of the material by the Rietveld method of X-ray diffraction (XRD) data revealed lindgrenite Cu3(MoO4)2(OH)2 in a single-phase structure. All the vibrational modes characteristic of the space group were identified by Raman vibrational and near-infrared (NIR) spectroscopies. The profile obtained for N2 adsorption/desorption was type III hysteresis, characteristic of mesoporous materials, with a surface area of 70.77(1) m2 g-1. The micrographs of the material obtained by scanning electron microscopy showed nanoplates with nanometric sizes and an anisotropic growth aspect. The catalytic activity of lindgrenite was evaluated by esterifying oleic acid with methanol, showing high conversion rate to methyl oleate and good catalyst stability after seven recycling cycles. Above all, the best catalytic performance was reached when we optimized parameters such as oleic acid:methanol molar ratio of 1:5, 5% of catalyst dosage, and reaction time of 5 h, resulting in 98.38% of conversion at 413 K. Therefore, sonochemically synthesized lindgrenite proved to be a high potential material for biofuel production by oleic acid esterification.

13.
Science ; 372(6541): 484-487, 2021 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-33926948

RESUMO

An estimated 90 to 95% of Indigenous people in Amazonia died after European contact. This population collapse is postulated to have caused decreases in atmospheric carbon dioxide concentrations at around 1610 CE, as a result of a wave of land abandonment in the wake of disease, slavery, and warfare, whereby the attendant reversion to forest substantially increased terrestrial carbon sequestration. On the basis of 39 Amazonian fossil pollen records, we show that there was no synchronous reforestation event associated with such an atmospheric carbon dioxide response after European arrival in Amazonia. Instead, we find that, at most sites, land abandonment and forest regrowth began about 300 to 600 years before European arrival. Pre-European pandemics, social strife, or environmental change may have contributed to these early site abandonments and ecological shifts.


Assuntos
Conservação dos Recursos Naturais/história , Florestas , Povos Indígenas/história , Dinâmica Populacional/história , Atmosfera/química , Brasil , Dióxido de Carbono/análise , Europa (Continente) , Fósseis , História do Século XVII , Humanos , Pólen/genética
14.
Br Poult Sci ; 62(5): 710-716, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33834908

RESUMO

1. Broiler breeders are subjected to qualitative or quantitative feed restrictions to prevent obesity, which causes major health and welfare problems. Diluting their feed by adding inert or low nutrient, bulky materials can reduce obesity, but the capacity of the gut needs to be determined to apply this strategy successfully. Two trials were conducted to measure the bulk capacity of Ross 308 broiler breeders prior to and after the onset of lay. The trial was completely randomised, with nine individually-caged breeders, with each cage as a replicate, totalling 189 birds per trial2. Birds were given ad libitum access to one of 21 maize-soyabean based feeds, an undiluted control or progressive dilution (10, 20, 30 and 40%) with either cellulose fibre, rice husk, sand, vermiculite or sawdust. Feeds were analysed for density, crude-, acid detergent- and neutral detergent-fibre, water-holding capacity (WHC), cation-exchange capacity and oil-holding capacity.2. In general, feed intake (scaled to body weight0.67) increased and then declined as the proportion of each diluent increased. Intake increased linearly when rice hulls and sand were used as diluents.3. Water holding capacity was the most appropriate measure to define the gut capacity of broiler breeders.4. The trial data was used to estimate the maximum-scaled feed intake (SFImax) in broiler breeders, which was 240-56.1WHC + 4.34WHC2 g/kg0.67/d.


Assuntos
Ração Animal , Galinhas , Ração Animal/análise , Animais , Peso Corporal , Ingestão de Alimentos
15.
Braz J Biol ; 82: e232868, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33681896

RESUMO

The "piaussu", Megaleporinus macrocephalus is an anostomatid fish species native to the basin of the Paraguay River, in the Pantanal biome of western Brazil. However, this species has now been recorded in a number of other drainages, including those of the upper Paraná, Uruguay, Jacuí, Doce, Mucuri, and Paraíba do Sulrivers. This study presents two new records of the occurrence of M. macrocephalus, in the basins of the Itapecuru and Mearim rivers in the state of Maranhão, in the Brazilian Northeast. The piaussu is a large-bodied fish of commercial interest that is widely raised on fish farms, and its occurrence in the Itapecuru and Mearim rivers is likely the result of individuals escaping from fish tanks when they overflow during the rainy season. Morphological analyses and sequences of the Cytochrome Oxidase Subunit I (COI) gene confirmed the taxonomic identification of the specimens as M. macrocephalus. The COI sequences were 99.66% similar to those of M. macrocephalus deposited in the BOLDSystems database. These records extend the known distribution of M. macrocephalus to the basins of the Itapecuru and Mearim rivers in the Brazilian Northeast, highlighting a new case of introduction of exotic fish species into Brazilian river basins.


Assuntos
Caraciformes , Rios , Animais , Brasil , Caraciformes/genética , Humanos , Paraguai , Uruguai
16.
Braz J Med Biol Res ; 54(4): e9806, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33624734

RESUMO

An increasing number of elderly people in renal support is expected in the coming years. The objective of this study was to report the clinical and socio-demographic data of end-stage renal disease (ESRD) adult patients undergoing regular dialysis treatment comparing elderly (≥65 years old) and non-elderly subjects using data from the Brazilian Dialysis Registry database. The regional distribution of the sample was Southeast (48.8%), South (33.7), Northeast (13.1%), Midwest (5.1%), and North (0.1%). A total of 18,030 patients were included in the analysis with elderly patients accounting for 29.5% of the sample. The elderly patients were predominantly male, white, retired, and literate. Elderly ESRD patients had a slightly higher frequency of undernourishment and a lower frequency of obesity than the non-elderly adults. A higher frequency of elderly patients were from the South and Southeast regions. The dialysis treatment of patients from both groups was predominantly funded by the public system, but the percent of non-public funding was higher for the elderly group. The most used initial access in the elderly was the central venous catheter and hemodialysis was the main modality at the beginning of treatment (93.2%), as well as during maintenance therapy (91.8%). Advanced age was associated with greater use of central venous catheter in the first dialysis session. The survival of the elderly on dialysis was lower than that of the non-elderly early in the course of dialysis and this difference increased over time. This is yet the largest national epidemiological study of elderly people on chronic dialysis.


Assuntos
Falência Renal Crônica , Diálise Renal , Adulto , Idoso , Brasil/epidemiologia , Demografia , Humanos , Rim , Falência Renal Crônica/epidemiologia , Falência Renal Crônica/terapia , Masculino , Pessoa de Meia-Idade
17.
Adv Protein Chem Struct Biol ; 124: 225-274, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33632466

RESUMO

Malaria is one of the most impacting public health problems in tropical and subtropical areas of the globe, with approximately 200 million cases worldwide annually. In the absence of an effective vaccine, rapid treatment is vital for effective malaria control. However, parasite resistance to currently available drugs underscores the urgent need for identifying new antimalarial therapies with new mechanisms of action. Among potential drug targets for developing new antimalarial candidates, protein kinases are attractive. These enzymes catalyze the phosphorylation of several proteins, thereby regulating a variety of cellular processes and playing crucial roles in the development of all stages of the malaria parasite life cycle. Moreover, the large phylogenetic distance between Plasmodium species and its human host is reflected in marked differences in structure and function of malaria protein kinases between the homologs of both species, indicating that selectivity can be attained. In this review, we describe the functions of the different types of Plasmodium kinases and highlight the main recent advances in the discovery of kinase inhibitors as potential new antimalarial drug candidates.


Assuntos
Antimaláricos/uso terapêutico , Sistemas de Liberação de Medicamentos , Malária , Plasmodium/enzimologia , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Quinases/metabolismo , Proteínas de Protozoários , Antimaláricos/química , Humanos , Malária/tratamento farmacológico , Malária/enzimologia , Inibidores de Proteínas Quinases/química , Proteínas de Protozoários/antagonistas & inibidores , Proteínas de Protozoários/metabolismo
18.
BMJ Mil Health ; 167(1): 59-62, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32409618

RESUMO

INTRODUCTION: Norovirus gastroenteritis is one of the most frequent causes of personnel unavailability in military units, being associated with significant morbidity and degradation of their operational effectiveness. The disease is usually mild but can be severe and life-threatening in young and healthy soldiers, who are prone to dehydration due to intensive daily activity. Despite its impact, the full extent of the norovirus gastroenteritis burden in military forces remains unclear. This systematic review aims to evaluate the impact and ascertain clinical and epidemiological features of norovirus outbreaks that have occurred in the military forces. METHODS: The systematic review followed the Preferred Reporting Items for Systemic Reviews and Meta-Analysis (PRISMA) guidelines and used three databases: PubMed, Scopus, and LILACs. Papers published up to 1 September 2019 were included without restrictions if they reported one or more outbreaks in the military forces on active duty, either on national territories or deployed overseas. RESULTS: A total of 343 papers were retrieved from the literature search. After inclusion/exclusion criteria a total of 39 eligible papers were considered. From 1988 (first reported outbreak in the military) to 2018 more than 101 norovirus outbreaks have been reported in the military, accounting for at least 24 332 cases. Secondary transmission was emphasised as the main route of norovirus transmission in the military forces, with eating outside the military setting an important route for the primary cases. CONCLUSIONS: The present review highlights that norovirus gastroenteritis has been a burden to military troops both in combat and on peacekeeping operations. Norovirus disease has been shown to exact a substantial toll on mission readiness and operational effectiveness. It is noteworthy that the impact of norovirus outbreaks among military units is underestimated because the literature review retrieved information from the armed forces from only nine countries.


Assuntos
Infecções por Caliciviridae/complicações , Surtos de Doenças/prevenção & controle , Medicina Militar/métodos , Infecções por Caliciviridae/epidemiologia , Infecções por Caliciviridae/transmissão , Humanos , Medicina Militar/tendências , Militares , Norovirus/efeitos dos fármacos , Norovirus/patogenicidade
19.
BMJ Mil Health ; 167(1): 40-43, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31278165

RESUMO

INTRODUCTION: Norovirus outbreaks frequently occur in communities and institutional settings acquiring a particular significance in armed forces where prompt reporting is critical. Here we describe the epidemiological, clinical and laboratorial investigation of a multicentre gastroenteritis outbreak that was detected simultaneously in three Portuguese army units with a common food supplier, Lisbon region, between 5 and 6 December 2017. METHODS: Questionnaires were distributed to all soldiers stationed in the three affected army units, and stool specimens were collected from soldiers with acute gastrointestinal illness. Stool specimens were tested for common enteropathogenic bacteria by standard methods and screened for a panel of enteric viruses using a multiplex real-time PCR assay. Food samples were also collected for microbiological analysis. Positive stool specimens for norovirus were further genotyped. RESULTS: The three simultaneous acute gastroenteritis outbreaks affected a 31 (3.5%) soldiers from a total of 874 stationed at the three units and lasted for 2 days. No secondary cases were reported. Stool specimens (N=11) were negative for all studied enteropathogenic agents but tested positive for norovirus. The recombinant norovirus GII.P16-GII.4 Sydney was identified in all positive samples with 100% identity. CONCLUSIONS: The results are suggestive of a common source of infection plausibly related to the food supplying chain. Although centralisation of food supplying in the army has economic advantages, it may contribute to the multifocal occurrence of outbreaks. A rapid intervention is key in the mitigation of outbreak consequences and in reducing secondary transmission.


Assuntos
Surtos de Doenças/estatística & dados numéricos , Instalações Militares/estatística & dados numéricos , Militares/estatística & dados numéricos , Infecções por Caliciviridae/epidemiologia , Fezes/virologia , Qualidade dos Alimentos , Gastroenterite/epidemiologia , Gastroenterite/virologia , Humanos , Norovirus/efeitos dos fármacos , Norovirus/patogenicidade , Portugal/epidemiologia , Inquéritos e Questionários
20.
Cryo Letters ; 42(4): 210-219, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35363840

RESUMO

BACKGROUND: Somatic tissue banks represent important tools for the conservation of wild mammals, aiming at the immediate maintenance and safeguarding of biological samples. For agouti, Dasyprocta leporina, studies on the formation of these banks are still scarce, especially regarding protocols of the best cryoprotectant solution employed. OBJECTIVE: To optimize the cryoprotectant solution [ethylene glycol (EG), dimethyl sulfoxide (DMSO), sucrose (SUC)] used for the cryopreservation of agouti somatic tissues. MATERIALS AND METHODS: We treated ear tissues with various cryoprotectant solutions: 3.0 M EG (EG group), 3.0 M EG and 0.25 M SUC (EG-SUC group), 3.0 M DMSO (DMSO group), 3.0 M DMSO and 0.25 M SUC (DMSO-SUC group), 1.5 M EG and 1.5 M DMSO (EG-DMSO group) and 1.5 M EG, 1.5 M DMSO and 0.25 M SUC (EG-DMSO-SUC group). Non-cryopreserved tissues were used as controls. All tissues were analyzed for their ultrastructural and morphometric characteristics by scanning electron microscopy and conventional histology. RESULTS: EG-DMSO-SUC was found to be the optimal cryoprotectant solution in terms of the evaluated parameters, such as thickness of the dermis and skin, number of perinuclear halos, proliferative potential, number of empty lacunas and degenerated chondrocytes. CONCLUSION: Agouti somatic tissue cryopreservation may serve for its conservation and as an experimental model for the development of preservation methods for species of the same genus that are either vulnerable or critically endangered.


Assuntos
Dasyproctidae , Animais , Criopreservação/métodos , Crioprotetores/farmacologia , Dimetil Sulfóxido/farmacologia , Etilenoglicol
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