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1.
PeerJ ; 12: e17087, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38623496

RESUMO

Background: Spodoptera frugiperda (FAW) is a pest that poses a significant threat to corn production worldwide, causing millions of dollars in losses. The species has evolved into two strains (corn and rice) that differ in their genetics, reproductive isolation, and resistance to insecticides and Bacillus thuringiensis endotoxins. The microbiota plays an important role in insects' physiology, nutrient acquisition, and response to chemical and biological controls. Several studies have been carried out on FAW microbiota from larvae guts using laboratory or field samples and a couple of studies have analyzed the corn strain microbiota across its life cycle. This investigation reveals the first comparison between corn strain (CS) and rice strain (RS) of FAW during different developmental insect stages and, more importantly, endosymbiont detection in both strains, highlighting the importance of studying both FAW populations and samples from different stages. Methods: The composition of microbiota during the life cycle of the FAW corn and rice strains was analyzed through high-throughput sequencing of the bacterial 16S rRNA gene using the MiSeq system. Additionally, culture-dependent techniques were used to isolate gut bacteria and the Transcribed Internal Spacer-ITS, 16S rRNA, and gyrB genes were examined to enhance bacterial identification. Results: Richness, diversity, and bacterial composition changed significantly across the life cycle of FAW. Most diversity was observed in eggs and males. Differences in gut microbiota diversity between CS and RS were minor. However, Leuconostoc, A2, Klebsiella, Lachnoclostridium, Spiroplasma, and Mucispirilum were mainly associated with RS and Colidextribacter, Pelomonas, Weissella, and Arsenophonus to CS, suggesting that FAW strains differ in several genera according to the host plant. Firmicutes and Proteobacteria were the dominant phyla during FAW metamorphosis. Illeobacterium, Ralstonia, and Burkholderia exhibited similar abundancies in both strains. Enterococcus was identified as a conserved taxon across the entire FAW life cycle. Microbiota core communities mainly consisted of Enterococcus and Illeobacterium. A positive correlation was found between Spiroplasma with RS (sampled from eggs, larvae, pupae, and adults) and Arsenophonus (sampled from eggs, larvae, and adults) with CS. Enterococcus mundtii was predominant in all developmental stages. Previous studies have suggested its importance in FAW response to B. thuringensis. Our results are relevant for the characterization of FAW corn and rice strains microbiota to develop new strategies for their control. Detection of Arsenophonus in CS and Spiroplasma in RS are promising for the improvement of this pest management, as these bacteria induce male killing and larvae fitness reduction in other Lepidoptera species.


Assuntos
Bacillus thuringiensis , Microbiota , Oryza , Animais , Masculino , Spodoptera/genética , Zea mays/genética , Oryza/genética , RNA Ribossômico 16S/genética , Estágios do Ciclo de Vida , Larva/genética , Bacillus thuringiensis/genética , Microbiota/genética
2.
Int J Biol Macromol ; 263(Pt 1): 130230, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38373564

RESUMO

Pectin is widely used in several products in the industry. Conventionally, strong and harmful acids are used for its extraction. This study optimized the extraction of orange peel's pectin using citric acid, considering yield and degree of esterification (DE) as response variables. Proximal analyses were performed, and the samples were subjected to a Box-Behnken design on three central points, considering as variables the temperature, time, and pH. The results of proximate analyses of the orange peels revealed 11.76 % moisture content, 87.26 % volatiles, 0.09 % ash, 50.45 % soluble carbohydrates, 70.60 % total carbohydrates, 0.89 % fixed carbon, 5.35 % lipids, and 36.75 mg GAE/g of phenolic compounds. The resulting second-order polynomial model described the relation of the input and output variables related to each other. The best performance to obtain a higher yield (18.18 %) of high methoxyl pectin (DE 50 %) was set at 100 °C/30 min/pH 2.48. Pectin showed antioxidant properties by ABTS and DPPH assays and similar thermal properties to the commercial polymer. Its equivalent weight was 1219.51 mol/g, and the methoxyl and anhydrouronic acid were 2.23 and 67.10 %, respectively. Hence, pectin extraction with citric acid results in a high-quality polymer and could be used as a gelling agent, stabilizer, or texturizer in food products.


Assuntos
Citrus sinensis , Pectinas , Pectinas/química , Citrus sinensis/química , Ácido Cítrico/química , Temperatura , Antioxidantes/farmacologia , Excipientes
3.
J Med Entomol ; 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38373261

RESUMO

Triatoma sanguisuga (Leconte) is one of the most widely distributed kissing bugs in the United States, associated with an extensive zoonotic circulation of Trypanosoma cruzi, the agent of Chagas disease, in a large part of the country. However, the actual risk for human infection in the United States is poorly understood. Here, we further assessed the ecology of T. sanguisuga bugs collected in residents' houses in Illinois and Louisiana, using a metagenomic approach to identify their blood-feeding sources, T. cruzi parasites and gut microbiota. Blood meal analysis revealed feeding on domestic animals (dogs, cats, pigs, goats, and turkeys), synanthropic species (raccoons, opossums, and squirrels), as well as the more sylvatic white-tail deer. Human blood was identified in 11/14 (78%) of bugs, highlighting a frequent vector-human contact. The infection rate with T. cruzi was 53% (8/15), and most infected bugs (6/8) had fed on humans. A total of 41 bacterial families were identified, with significant differences in microbiota alpha and beta diversity between bugs from Louisiana and Illinois. However, predicted metabolic functions remained highly conserved, suggesting important constraints to fulfill their role in bug biology. These results confirmed a significant risk for vector-borne transmission of T. cruzi to humans in Louisiana and Illinois, which warrants more active screening for human infections. Also, while there is broad plasticity in the bacterial composition of T. sanguisuga microbiota, there are strong constraints to preserve metabolic profile and function, making it a good target for novel vector control strategies.

4.
Emerg Microbes Infect ; 13(1): 2315964, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38381980

RESUMO

Chagas Disease is an important neglected tropical disease caused by Trypanosoma cruzi. There is no gold standard for diagnosis and commercial serological tests perform poorly in certain locations. By aligning T. cruzi genomes covering parasite genetic and geographic diversity, we identified highly conserved proteins that could serve as universal antigens for improved diagnosis. Their antigenicity was tested in high-density peptide microarrays using well-characterized plasma samples, including samples presenting true infections but discordant serology. Individual and combination of epitopes were also evaluated in peptide-ELISAs. We identified >1400 highly conserved T. cruzi proteins evaluated in microarrays. Remarkably, T. cruzi positive controls had a different epitope recognition profile compared to serologically discordant samples. In particular, multiple T. cruzi antigens used in current tests and their strain-variants, and novel epitopes thought to be broadly antigenic failed to be recognized by discordant samples. Nonetheless, >2000 epitopes specifically recognized by IgGs from both positive controls and discordant samples were identified. Evaluation of selected peptides in ELISA further illustrated the extensive variation in antibody profiles among subjects and a peptide combination could outperform a commercial ELISA, increasing assay sensitivity from 52.3% to 72.7%. Individual variation in antibody profiles rather than T. cruzi diversity appears to be the main factor driving differences in serological diagnostic performance according to geography, which will be important to further elucidate. ELISA with a combination of peptides recognized by a greater number of individuals could better capture infections, and further development may lead to an optimal antigen mixture for a universal diagnostic assay.


Assuntos
Doença de Chagas , Trypanosoma cruzi , Humanos , Trypanosoma cruzi/genética , Trypanosoma cruzi/química , Antígenos de Protozoários/genética , Doença de Chagas/diagnóstico , Doença de Chagas/parasitologia , Epitopos/genética , Ensaio de Imunoadsorção Enzimática , Peptídeos
5.
Neural Regen Res ; 19(9): 2057-2067, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38227536

RESUMO

JOURNAL/nrgr/04.03/01300535-202409000-00039/figure1/v/2024-01-16T170235Z/r/image-tiff Parkinsonism by unilateral, intranigral ß-sitosterol ß-D-glucoside administration in rats is distinguished in that the α-synuclein insult begins unilaterally but spreads bilaterally and increases in severity over time, thus replicating several clinical features of Parkinson's disease, a typical α-synucleinopathy. As Nurr1 represses α-synuclein, we evaluated whether unilateral transfected of rNurr1-V5 transgene via neurotensin-polyplex to the substantia nigra on day 30 after unilateral ß-sitosterol ß-D-glucoside lesion could affect bilateral neuropathology and sensorimotor deficits on day 30 post-transfection. This study found that rNurr1-V5 expression but not that of the green fluorescent protein (the negative control) reduced ß-sitosterol ß-D-glucoside-induced neuropathology. Accordingly, a bilateral increase in tyrosine hydroxylase-positive cells and arborization occurred in the substantia nigra and increased tyrosine hydroxylase-positive ramifications in the striatum. In addition, tyrosine hydroxylase-positive cells displayed less senescence marker ß-galactosidase and more neuron-cytoskeleton marker ßIII-tubulin and brain-derived neurotrophic factor. A significant decrease in activated microglia (positive to ionized calcium-binding adaptor molecule 1) and neurotoxic astrocytes (positive to glial fibrillary acidic protein and complement component 3) and increased neurotrophic astrocytes (positive to glial fibrillary acidic protein and S100 calcium-binding protein A10) also occurred in the substantia nigra. These effects followed the bilateral reduction in α-synuclein aggregates in the nigrostriatal system, improving sensorimotor behavior. Our results show that unilateral rNurr1-V5 transgene expression in nigral dopaminergic neurons mitigates bilateral neurodegeneration (senescence and loss of neuron-cytoskeleton and tyrosine hydroxylase-positive cells), neuroinflammation (activated microglia, neurotoxic astrocytes), α-synuclein aggregation, and sensorimotor deficits. Increased neurotrophic astrocytes and brain-derived neurotrophic factor can mediate the rNurr1-V5 effect, supporting its potential clinical use in the treatment of Parkinson's disease.

6.
Sci Rep ; 14(1): 1412, 2024 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-38228608

RESUMO

Chagas disease is a leading cause of non-ischemic cardiomyopathy in endemic regions of Central and South America. In Belize, Triatoma dimidiata sensu lato has been identified as the predominate taxon but vectorial transmission of Chagas disease is considered to be rare in the country. We recently identified an acute case of vector-borne Chagas disease in the northern region of Belize. Here we present a subsequent investigation of triatomines collected around the case-patient's home. We identified yet undescribed species, closely related to Triatoma huehuetenanguensis vector by molecular systematics methods occurring in the peridomestic environment. The identification of a T. cruzi-positive, novel species of Triatoma in Belize indicates an increased risk of transmission to humans in the region and warrants expanded surveillance and further investigation.


Assuntos
Doença de Chagas , Triatoma , Trypanosoma cruzi , Animais , Humanos , Belize , Trypanosoma cruzi/genética , Insetos Vetores
7.
Microbes Infect ; 26(1-2): 105240, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37866547

RESUMO

Trypanosoma cruzi is a protozoan parasite causing Chagas disease, with a complex life cycle involving different stages in insect vectors and mammalian hosts. Amastigotes are an intracellular form that replicates in the cytoplasm of host cells, and recent studies suggested that dormant forms may be contributing to parasite persistence, suggesting cellular heterogeneity among amastigotes. We investigated here if a transcriptomic approach could identify some heterogeneity in intracellular amastigotes and identify a dormant population. We used gene expression data derived from bulk RNA-sequencing of T. cruzi infection of human fibroblasts for deconvolution using CDSeq, which allows to simultaneously estimate amastigote cell-type proportions and cell-type-specific expression profiles. Six amastigote subpopulations were identified, confirming intracellular amastigotes heterogeneity, and one population presented characteristics of non-replicative dormant parasites, based on replication markers and TcRAD51 expression. Transcriptomic approaches appear to be powerful to understand T. cruzi cell differentiation and expansion of these studies could provide further insight on the role different cell types in parasite persistence and Chagas disease pathogenesis.


Assuntos
Doença de Chagas , Parasitos , Trypanosoma cruzi , Animais , Humanos , Trypanosoma cruzi/genética , Parasitos/genética , Doença de Chagas/parasitologia , Perfilação da Expressão Gênica , Citoplasma/metabolismo , Mamíferos
8.
Microorganisms ; 11(12)2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-38138010

RESUMO

Antibiotic resistance is a significant threat to public health worldwide. Genome-wide association studies (GWAS) have emerged as a powerful tool to identify genetic variants associated with this antibiotic resistance. By analyzing large datasets of bacterial genomes, GWAS can provide valuable insights into the resistance mechanisms and facilitate the discovery of new drug targets. The present study aimed to undertake a systematic review of different GWAS approaches used for detecting genetic variants associated with antibiotic resistance. We comprehensively searched the PubMed and Scopus databases to identify relevant studies published from 2013 to February 2023. A total of 40 studies met our inclusion criteria. These studies explored a wide range of bacterial species, antibiotics, and study designs. Notably, most of the studies were centered around human pathogens such as Mycobacterium tuberculosis, Escherichia coli, Neisseria gonorrhoeae, and Staphylococcus aureus. The review seeks to explore the several GWAS approaches utilized to investigate the genetic mechanisms associated with antibiotic resistance. Furthermore, it examines the contributions of GWAS approaches in identifying resistance-associated genetic variants through binary and continuous phenotypes. Overall, GWAS holds great potential to enhance our understanding of bacterial resistance and improve strategies to combat infectious diseases.

9.
Trop Med Infect Dis ; 8(12)2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38133447

RESUMO

Chagas disease is a public health problem in the Americas, from the southern United States (USA) to Argentina. In the USA, less than 1% of domestic cases have been identified and less than 0.3% of total cases have received treatment. Little is known about affected immigrant Latin American communities. A prospective study was conducted to assess knowledge about Chagas disease among the Latin American community living in the Greater New Orleans area. Participants answered a baseline questionnaire, viewed a short educational video presentation, completed a post-presentation questionnaire, and were screened with an FDA-approved blood rapid diagnostic test (RDT). A total of 154 participants from 18 Latin American countries (n = 138) and the USA (n = 16) were enrolled and screened for Trypanosoma cruzi infection. At baseline, 57% of the participants knew that Chagas disease is transmitted through an insect vector, and 26% recognized images of the vector. Following the administration of an educational intervention, the participants' knowledge regarding vector transmission increased to 91% and 35% of participants were able to successfully identify images of the vector. Five participants screened positive for T. cruzi infection, indicating a 3.24% [95%CI: 1.1-7.5%] prevalence of Trypanosoma cruzi infection within the Latin American community of the New Orleans area. Results highlight the urgent need for improving access to education and diagnostics of Chagas disease.

10.
Res Sq ; 2023 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-37961272

RESUMO

A vaccine against Trypanosoma cruzi, the agent of Chagas disease, would be an excellent additional tool for disease control. A recombinant vaccine based on Tc24 and TSA1 parasite antigens was found to be safe and immunogenic in naïve macaques. Here we performed a transcriptomic analysis of PBMC responses to vaccination, to shed light on the immunogenicity of this vaccine and guide the optimization of doses and formulation. RNA-sequencing analysis indicated a clear transcriptomic response of PBMCs from macaques after three vaccine doses, with the up-regulation of several immune cell activation pathways and a broad non-polarized immune profile. Analysis of the IgG repertoire showed that it had a rapid turnover with novel IgGs produced following each vaccine dose, while the TCR repertoire presented several persisting clones that were expanded after each vaccine dose. These data suggest that three vaccine doses may be needed for optimum immunogenecity and support the further evaluation of the protective efficacy of this vaccine.

11.
Microbiol Spectr ; : e0423622, 2023 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-37668388

RESUMO

Chronic Chagasic cardiomyopathy develops years after infection in 20-40% of patients, but disease progression is poorly understood. Here, we assessed Trypanosoma cruzi parasite dynamics and pathogenesis over a 2.5-year period in naturally infected rhesus macaques. Individuals with better control of parasitemia were infected with a greater diversity of parasite strains compared to those with increasing parasitemia over time. Also, the in vivo parasite multiplication rate decreased with increasing parasite diversity, suggesting competition among strains or a stronger immune response in multiple infections. Significant differences in electrocardiographic (ECG) profiles were observed in Chagasic macaques compared to uninfected controls, suggesting early conduction defects, and changes in ECG patterns over time were observed only in macaques with increasing parasitemia and lower parasite diversity. Disease progression was also associated with plasma fibronectin degradation, which may serve as a biomarker. These data provide a novel framework for the understanding of Chagas disease pathogenesis, with parasite diversity shaping disease progression.IMPORTANCEChagas disease progression remains poorly understood, and patients at increased risk of developing severe cardiac disease cannot be distinguished from those who may remain asymptomatic. Monitoring of Trypanosoma cruzi strain dynamics and pathogenesis over 2-3 years in naturally infected macaques shows that increasing parasite diversity in hosts is detrimental to parasite multiplication and Chagasic cardiomyopathy disease progression. This provides a novel framework for the understanding of Chagas disease pathogenesis.

12.
PeerJ ; 11: e15916, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37719127

RESUMO

Background: Spodoptera frugiperda (or fall armyworm, FAW) is a polyphagous pest native to Western Hemisphere and recently discovered in the Eastern Hemisphere. In Colombia, S. frugiperda is recognized as a pest of economic importance in corn. The species has genetically differentiated into two host populations named "corn" and "rice" strains. In 2012, a study made in central Colombia demonstrated that the corn strain is less susceptible to Bacillus thuringiensis (Bt) endotoxins (Cry1Ac and Cry 1Ab) than the rice strain. In this country, Bt transgenic corn has been extensively produced over the last 15 years. Since gut microbiota plays a role in the physiology and immunity of insects, and has been implicated in promoting the insecticidal activity of Bt, in this study an analysis of the interaction between Bt endotoxins and FAW gut microbiota was made. Also, the detection of endosymbionts was performed here, as they might have important implications in the biological control of a pest. Methods: The composition and diversity of microbiomes associated with larval specimens of S. frugiperda(corn strain) was investigated in a bioassay based on six treatments in the presence/absence of Bt toxins and antibiotics (Ab) through bacterial isolate analyses and by high throughput sequencing of the bacterial 16S rRNA gene. Additionally, species specific primers were used, to detect endosymbionts from gonads in S. frugiperda corn strain. Results: Firmicutes, Proteobacteria and Bacteroidota were the most dominant bacterial phyla found in S. frugiperda corn strain. No significant differences in bacteria species diversity and richness among the six treatments were found. Two species of Enterococcus spp., E. mundtii and E. casseliflavus were detected in treatments with Bt and antibiotics, suggesting that they are less susceptible to both of them. Additionally, the endosymbiont Arsenophonus was also identified on treatments in presence of Bt and antibiotics. The results obtained here are important since little knowledge exists about the gut microbiota on this pest and its interaction with Bt endotoxins. Previous studies made in Lepidoptera suggest that alteration of gut microbiota can be used to improve the management of pest populations, demonstrating the relevance of the results obtained in this work.


Assuntos
Bacillus thuringiensis , Microbiota , Animais , Spodoptera , Larva , Bacillus thuringiensis/genética , Endotoxinas , RNA Ribossômico 16S/genética , Microbiota/genética , Antibacterianos
13.
Polymers (Basel) ; 15(18)2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37765557

RESUMO

In this paper, we discuss the creation of a hybrid magnetorheological elastomer that combines nano- and microparticles. The mixture contained 45 wt.% fillers, with combinations of either 0% nanoparticles and 100% microparticles or 25% nanoparticles and 75% microparticles. TGA and FTIR testing confirmed the materials' thermal and chemical stability, while an SEM analysis determined the particles' size and morphology. XRD results were used to determine the crystal size of both nano- and microparticles. The addition of reinforcing particles, particularly nanoparticles, enhanced the stiffness of the composite materials studied, but their overall strength was only minimally affected. The computed interaction parameter relative to the volume fraction was consistent with the previous literature. Furthermore, the study observed a magnetic response increment in composite materials reinforced with nanoparticles above 30 Hz. The isotropic material containing only microparticles had a lower storage modulus than the isotropic sample with nanoparticles without a magnetic field. However, when a magnetic field was applied, the material with only microparticles exhibited a higher storage modulus than the samples with nanoparticles.

14.
Polymers (Basel) ; 15(18)2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37765633

RESUMO

Dimensional analysis through the Buckingham Pi theorem was confirmed as an efficient mathematical tool to model the otherwise non-linear high order ultrasonic micro-injection molding process (UMIM). Several combinations of processing conditions were evaluated to obtain experimental measurements and validate the derived equations. UMIM processing parameters, output variable energy consumption, and final specimen's Young modulus were arranged in dimensionless groups and formulated as functional relationships, which lead to dimensionless equations that predict output variables as a function of the user-specified processing parameters and known material properties.

15.
Horiz. sanitario (en linea) ; 22(2): 255-261, may.-ago. 2023. tab, graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1534535

RESUMO

Resumen Objetivo: Describir el efecto de la percepción de riesgo y la religiosidad sobre el consumo de marihuana en adolescentes de zonas marginales del Estado de Chihuahua, Chihuahua. Materiales y métodos: Estudio descriptivo correlacional. El muestreo fue probabilístico aleatorio simple. La muestra final fue de 248 adolescentes de 12 a 17 años de zonas marginales de Chihuahua. Se utilizó una cédula de datos personales, inventario de religiosidad y la escala de percepción de riesgo. Resultados: El 59.3% de los adolescentes entrevistados fueron hombres, 59.7% católico y 23% cristiano. El 16.1% indicó consumo de marihuana alguna vez en la vida y 6.5% en el último año. El modelo de regresión logística de las variables de religiosidad y percepción de riesgo mostró una varianza explicada del 19% para el consumo de marihuana alguna vez en la vida, destacando que a mayor percepción de riesgo (β=-0.032, p<0.001) y mayor índice de religiosidad (β=-0.023, p<0.001) menor es la probabilidad del consumo de marihuana. Conclusiones: La percepción de riesgo y la religiosidad en adolescentes de zonas marginales muestran ser factores protectores para el consumo de marihuana. Estos resultados deben ser considerados en programas de prevención para el consumo de drogas en poblaciones marginales.


Abstract Objective: To describe the effect of the perception of risk and religiosity on the consumption of marijuana in adolescents from marginal areas of the State of Chihuahua, Chihuahua. Materials and methods: Study descriptive correlational design. The sampling was simple random probabilistic. The final sample consisted of 248 adolescents between the ages of 12 and 17 from marginal areas of Chihuahua. A personal data card, religiosity inventory and the risk perception scale were used. Results: 59.3% of the adolescents interviewed were men, of whom 59.7% said they were Catholic and 23% Christian. 16.1% indicated marijuana use at some time in their life, and 6.5% in the last year. The logistic regression model of the religiosity and risk perception variables showed an explained variance of 19% for marijuana use at some time in life, highlighting that the higher the risk perception (β=-0.032, p<.001) and a higher religiosity index (β=-0.023, p<0.001), the lower the probability of marijuana use. Conclusions: Risk perception and religiosity in adolescents from marginal areas show to be protective factors for marijuana use. These results should be analyzed in greater depth to be considered in prevention programs for drug use in marginal populations.

16.
Polymers (Basel) ; 15(14)2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37514439

RESUMO

In recent years, there has been a growing demand for biocompatible medical devices on the microscale. However, the manufacturing of certain microfeatures has posed a significant challenge. To address this limitation, a new process called ultrasonic injection molding or ultrasonic molding (USM) has emerged as a potential solution. In this study, we focused on the production of a specific microdevice known as Hem-O-Lok, which is designed for ligation and tissue repair during laparoscopic surgery. Utilizing USM technology, we successfully manufactured the microdevice using a nonabsorbable biopolymer that offers the necessary flexibility for easy handling and use. To ensure high-quality microdevices, we extensively investigated various processing parameters such as vibration amplitude, temperature, and injection velocity. Through careful experimentation, we determined that the microdevice achieved optimal quality when manufactured under conditions of maximum vibrational amplitude and temperatures of 50 and 60 °C. This conclusion was supported by measurements of critical microfeatures. Additionally, our materials characterization efforts revealed the presence of a carbonyl (C=O) group resulting from the thermo-oxidation of air in the plasticizing chamber. This finding contributes to the enhanced thermal stability of the microdevices within a temperature range of 429-437 °C.

17.
Trop Med Infect Dis ; 8(5)2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-37235325

RESUMO

Chagas disease, caused by the protozoa parasite Trypanosoma cruzi, is an anthropozoonosis that represents a major public health problem in the Americas, affecting 7 million people with at least 65 million at risk. We sought to assess the intensity of disease surveillance based on diagnostic test requests from hospitals in New Orleans, Louisiana. We extracted information from send-out labs at two major tertiary academic hospitals in New Orleans, Louisiana, USA, from 1 January 2018 to 1 December 2020. We found that in these three years there were 27 patients for whom Chagas disease testing was ordered. Most of these patients were male (70%), with a median age of 40 years old, and their most common ethnical background was Hispanic (74%). These findings demonstrate undertesting of this neglected disease in our region. Given the low Chagas disease surveillance, we need to increase awareness, health promotion, and education among healthcare workers.

19.
Med. clin. soc ; 7(1)abr. 2023.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1422067

RESUMO

Introducción: La toxoplasmosis es una enfermedad parasitaria, en América Latina la prevalencia es relativamente alta, se sabe que la enfermedad no solo es la causa más frecuente de uveítis posterior, sino también la causa principal de la uveítis en sí misma. En Paraguay no se dispone de datos epidemiológicos publicados sobre la misma. Objetivo: Determinar las características de las lesiones retinianas en pacientes con diagnóstico de Toxoplasmosis ocular. Metodología: El presente estudio es observacional, descriptivo, de corte transversal, temporalmente retrospectivo, con muestreo no probabilístico de casos consecutivos. Se enfocó en pacientes con diagnóstico de Toxoplasmosis que acudieron al servicio de Oftalmología del Hospital de Clínicas, durante el periodo de junio de 2020 a febrero 2022. Resultados: Se observó un 54,3 % de mujeres, una media de 30,62 +/- 12,96 años y un 62,8 % de procedencia urbana. El 88,3 % de los casos fueron unilaterales, la mitad de episodios primarios, el 93,6 % casos agudos, y el 97,9 % tuvo un mecanismo de trasmisión adquirido. La mayoría se presentó como Panuveítis, las localizaciones más frecuentes de las lesiones retinocoroideas fueron el Polo posterior (extramacular) y la periferia. El principal abordaje terapéutico fue el tratamiento con Trimetoprim Sulfametoxazol y corticoides sistémicos, la duración del tratamiento fue de 6,51 +/- 1,52 semanas, y las principales complicaciones fueron la Vitritis residual y la Hipertensión ocular. Discusión: La toxoplasmosis ocular es una causa importante de morbilidad visual. Se hace fundamental la prevención de la infección por este parásito mediante medidas higiénico-sanitarias, así como el diagnóstico y tratamiento precoz de los pacientes infectados, de tal manera a disminuir las complicaciones asociadas a esta patología.


Introduction: Toxoplasmosis is a parasitic disease, in Latin America the prevalence is relatively high, it is known that the disease is not only the most frequent cause of posterior uveitis, but also the main cause of uveitis itself. In Paraguay there are no published epidemiological data on it. Objective: To determine the characteristics of retinal lesions in patients diagnosed with ocular Toxoplasmosis. Methods: This study is observational, descriptive, cross-sectional, temporally retrospective, with non-probabilistic sampling of consecutive cases. It focused on patients diagnosed with Toxoplasmosis who attended the Ophthalmology service of the Hospital de Clínicas, during the period from June 2020 to February 2022. Results: 54.3% of women were observed, an average of 30.62 +/ - 12.96 years old and 62.8% of urban origin. 88.3% of the cases were unilateral, half were primary episodes, 93.6% acute cases, and 97.9% had an acquired transmission mechanism. Most presented as panuveitis, the most frequent locations of retinochoroidal lesions were the posterior pole (extramacular) and the periphery. The main therapeutic approach was treatment with trimethoprim sulfamethoxazole and systemic corticosteroids, the duration of treatment was 6.51 +/- 1.52 weeks, and the main complications were residual vitritis and ocular hypertension. Discussion: Ocular toxoplasmosis is an important cause of visual morbidity. It is essential to prevent infection by this parasite through hygienic-sanitary measures, as well as early diagnosis and treatment of infected patients, in order to reduce the complications associated with this pathology.

20.
J Clin Med ; 12(6)2023 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-36983335

RESUMO

BACKGROUND: Antibody-mediated rejection (AMR) is one of the most important challenges in the context of renal transplantation, because the binding of de novo donor-specific antibodies (dnDSA) to the kidney graft triggers the activation of the complement, which in turn leads to loss of transplant. In this context, the objective of this study was to evaluate the association between complement-fixing dnDSA antibodies and graft loss as well as the possible association between non-complement-fixing antibodies and transplanted organ survival in kidney transplant recipients. METHODS: Our study included a cohort of 245 transplant patients over a 5-year period at Virgen de las Nieves University Hospital (HUVN) in Granada, Spain. RESULTS: dnDSA was observed in 26 patients. Of these patients, 17 had non-complement-fixing dnDSA and 9 had complement-fixing dnDSA. CONCLUSIONS: Our study demonstrated a significant association between the frequency of rejection and renal graft loss and the presence of C1q-binding dnDSA. Our results show the importance of the individualization of dnDSA, classifying them according to their ability to activate the complement, and suggest that the detection of complement-binding capacity by dnDSA could be used as a prognostic marker to predict AMR outcome and graft survival in kidney transplant patients who develop dnDSA.

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