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1.
Nature ; 594(7861): 51-56, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-34079136

RESUMEN

In perovskite solar cells, doped organic semiconductors are often used as charge-extraction interlayers situated between the photoactive layer and the electrodes. The π-conjugated small molecule 2,2',7,7'-tetrakis[N,N-di(4-methoxyphenyl)amino]-9,9-spirobifluorene (spiro-OMeTAD) is the most frequently used semiconductor in the hole-conducting layer1-6, and its electrical properties considerably affect the charge collection efficiencies of the solar cell7. To enhance the electrical conductivity of spiro-OMeTAD, lithium bis(trifluoromethane)sulfonimide (LiTFSI) is typically used in a doping process, which is conventionally initiated by exposing spiro-OMeTAD:LiTFSI blend films to air and light for several hours. This process, in which oxygen acts as the p-type dopant8-11, is time-intensive and largely depends on ambient conditions, and thus hinders the commercialization of perovskite solar cells. Here we report a fast and reproducible doping method that involves bubbling a spiro-OMeTAD:LiTFSI solution with CO2 under ultraviolet light. CO2 obtains electrons from photoexcited spiro-OMeTAD, rapidly promoting its p-type doping and resulting in the precipitation of carbonates. The CO2-treated interlayer exhibits approximately 100 times higher conductivity than a pristine film while realizing stable, high-efficiency perovskite solar cells without any post-treatments. We also show that this method can be used to dope π-conjugated polymers.

2.
J Biomed Sci ; 31(1): 48, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38730462

RESUMEN

Retinal degenerative diseases, including diabetic retinopathy (DR) and age-related macular degeneration (AMD), loom as threats to vision, causing detrimental effects on the structure and function of the retina. Central to understanding these diseases, is the compromised state of the blood-retinal barrier (BRB), an effective barrier that regulates the influx of immune and inflammatory components. Whether BRB breakdown initiates retinal distress, or is a consequence of disease progression, remains enigmatic. Nevertheless, it is an indication of retinal dysfunction and potential vision loss.The intricate intercellular dialogues among retinal cell populations remain unintelligible in the complex retinal milieu, under conditions of inflammation and oxidative stress. The retina, a specialized neural tissue, sustains a ceaseless demand for oxygen and nutrients from two vascular networks. The BRB orchestrates the exchange of molecules and fluids within this specialized region, comprising the inner BRB (iBRB) and the outer BRB (oBRB). Extracellular vesicles (EVs) are small membranous structures, and act as messengers facilitating intercellular communication in this milieu.EVs, both from retinal and peripheral immune cells, increase complexity to BRB dysfunction in DR and AMD. Laden with bioactive cargoes, these EVs can modulate the retinal microenvironment, influencing disease progression. Our review delves into the multifaceted role of EVs in retinal degenerative diseases, elucidating the molecular crosstalk they orchestrate, and their microRNA (miRNA) content. By shedding light on these nanoscale messengers, from their biogenesis, release, to interaction and uptake by target cells, we aim to deepen the comprehension of BRB dysfunction and explore their therapeutic potential, therefore increasing our understanding of DR and AMD pathophysiology.


Asunto(s)
Barrera Hematorretinal , Vesículas Extracelulares , Barrera Hematorretinal/metabolismo , Barrera Hematorretinal/fisiopatología , Vesículas Extracelulares/metabolismo , Humanos , Retinopatía Diabética/fisiopatología , Retinopatía Diabética/metabolismo , Enfermedades de la Retina/fisiopatología , Enfermedades de la Retina/metabolismo , Degeneración Macular/fisiopatología , Degeneración Macular/metabolismo , Animales
3.
BMC Med Educ ; 24(1): 446, 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38658926

RESUMEN

BACKGROUND: This research evaluated whether the relationships between factors of resilience, self-esteem, depression, and anxiety in dental students with changes in teaching and learning methods. We also studied the psychological impact of face-to-face lectures during the COVID-19 pandemic. METHODS: This cross-sectional descriptive study used Google Forms to collect data with the Rosenberg Self-Esteem Scale (RSE), Connor-Davidson Risk Resilience Scale (CD-RISC), Beck Anxiety Inventory (BAI), and Beck Depression Inventory (BDI and BDI-II). An open-ended question was also asked about important learning difficulties. RESULTS: The analysis revealed very high levels of resilience (30.23 ± 5.84), self-esteem in the normal range (29.08 ± 4.03), minimal depression levels (12.32 ± 8.05), and low anxiety levels (17.20 ± 12.41). There were no significant differences between sociodemographic variables ranges in regard to all psychological questionnaires. No high levels of depression and anxiety were found. CONCLUSIONS: The levels were low compared to other studies in which online teaching was used, which is explained by the fact that the students retained adequate resilience and self-esteem thanks to being able to contact teachers and, above all, their own peers.


Asunto(s)
Ansiedad , COVID-19 , Depresión , Resiliencia Psicológica , Autoimagen , Estudiantes de Odontología , Humanos , COVID-19/epidemiología , COVID-19/psicología , Estudios Transversales , Estudiantes de Odontología/psicología , Femenino , Masculino , Depresión/epidemiología , Depresión/psicología , Ansiedad/epidemiología , Adulto Joven , Adulto , Educación en Odontología , Pandemias , Educación a Distancia , SARS-CoV-2 , Encuestas y Cuestionarios
4.
Water Sci Technol ; 89(5): 1240-1251, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38483495

RESUMEN

The accelerated growth of cyanobacteria in water bodies is a global critical environmental issue caused by continuous discharges of effluents into the environment that are rich in phosphorus and nitrogen. So, cyanobacteria have found propitious conditions for proliferation, provoking significant ecological imbalances. Cyanobacteria produce cyanotoxins, which are harmful to life, and compounds like 2-methylisoborneol and geosmin that affect water's taste and odor. This study analyzed a long-term database of important environmental parameters from a tropical reservoir in São Paulo State, Brazil. The statistical methods of correlation matrices and principal component analysis were used. Data analysis revealed a significant relationship between cyanobacteria growth and high levels of phosphate and nitrogen. Furthermore, positive correlations were found among concentrations of biocidal elements like antimony, arsenic, and selenium related to cyanobacterial bloomings. These correlations can be attributed to agricultural wastewaters and/or possible algicide used to control these microorganisms.


Asunto(s)
Cianobacterias , Calidad del Agua , Brasil , Agricultura , Nitrógeno
5.
Exp Eye Res ; 235: 109627, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37619829

RESUMEN

The main purpose of this study is to analyze the effects of unilateral optic nerve crush in the gene expression of pro- and anti-inflammatory mediators, and gliosis markers in injured and contralateral retinas. Retinas from intact, unilaterally optic nerve injured or sham-operated C57BL/6J mice were analyzed 1, 3, 9 and 30 days after the surgery (n = 5/group and time point) and the relative expression of TGF-ß1, IL-1ß, TNF-α, Iba1, AQP4, GFAP, MHCII, and TSPO was analyzed in injured and contralateral using qPCR. The results indicated that compared with intact retinas, sham-operated animals showed an early (day 1) upregulation of IL-1ß, TNF-α and TSPO and a late (day 30) upregulation of TNF-α. In sham-contralateral retinas, TNF-α and TSPO mRNA expression were upregulated and day 30 while GFAP, Iba1, AQP4 and MHCII downregulated at day 9. Compared with sham-operated animals, in retinas affected by optic nerve crush GFAP and TSPO upregulated at day 1 and TNF-α, Iba1, AQP4 and MHCII at day 3. In the crushed-contralateral retinas, TGF-ß1, TNF-α, Iba1 and MHCII were upregulated at day 1. TSPO was upregulated up to day 30 whereas TGF-ß1 and Iba1 downregulated after day 9. In conclusion, both sham surgery and optic nerve crush changed the profile of inflammatory and gliosis markers in the injured and contralateral retinas, changes that were more pronounced for optic nerve crush when compared to sham.


Asunto(s)
Traumatismos del Nervio Óptico , Factor de Crecimiento Transformador beta1 , Ratones , Animales , Factor de Crecimiento Transformador beta1/farmacología , Células Ganglionares de la Retina/metabolismo , Gliosis/metabolismo , Traumatismos del Nervio Óptico/genética , Traumatismos del Nervio Óptico/metabolismo , Enfermedades Neuroinflamatorias , Factor de Necrosis Tumoral alfa/metabolismo , Ratones Endogámicos C57BL , Retina/metabolismo , Nervio Óptico/metabolismo , Compresión Nerviosa/métodos
6.
Sensors (Basel) ; 23(4)2023 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-36850872

RESUMEN

Currently, few experimental methods exist that enable the mechanical characterization of adhesives under high strain rates. One such method is the Split Hopkinson Bar (SHB) test. The mechanical characterization of adhesives is performed using different specimen configurations, such as Single Lap Joint (SLJ) specimens. A gripping system, attached to the bars through threading, was conceived to enable the testing of SLJs. An optimization study for selecting the best thread was performed, analyzing the thread type, the nominal diameter, and the thread pitch. Afterwards, the gripping system geometry was numerically evaluated. The optimal threaded connection for the specimen consists of a trapezoidal thread with a 14 mm diameter and a 2 mm thread pitch. To validate the gripping system, the load-displacement (P-δ) curve of an SLJ, which was simulated as if it were tested on the SHB apparatus, was compared with an analogous curve from a validated drop-weight test numerical model.

7.
Int J Mol Sci ; 24(4)2023 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-36834893

RESUMEN

Retinal organotypic cultures (ROCs) are used as an in vivo surrogate to study retinal ganglion cell (RGC) loss and neuroprotection. In vivo, the gold standard to study RGC degeneration and neuroprotection is optic nerve lesion. We propose here to compare the course of RGC death and glial activation between both models. The left optic nerve of C57BL/6 male mice was crushed, and retinas analyzed from 1 to 9 days after the injury. ROCs were analyzed at the same time points. As a control, intact retinas were used. Retinas were studied anatomically to assess RGC survival, microglial, and macroglial activation. Macroglial and microglial cells showed different morphological activation between models and were activated earlier in ROCs. Furthermore, microglial cell density in the ganglion cell layer was always lower in ROCs than in vivo. RGC loss after axotomy and in vitro followed the same trend up to 5 days. Thereafter, there was an abrupt decrease in viable RGCs in ROCs. However, RGC somas were still immuno-identified by several molecular markers. ROCs are useful for proof-of-concept studies on neuroprotection, but long-term experiments should be carried out in vivo. Importantly, the differential glial activation observed between models and the concomitant death of photoreceptors that occurs in vitro may alter the efficacy of RGC neuroprotective therapies when tested in in vivo models of optic nerve injury.


Asunto(s)
Sistemas Microfisiológicos , Traumatismos del Nervio Óptico , Ratones , Animales , Masculino , Ratones Endogámicos C57BL , Retina/metabolismo , Traumatismos del Nervio Óptico/metabolismo , Células Ganglionares de la Retina/metabolismo , Axotomía , Supervivencia Celular
8.
J Neurochem ; 163(2): 113-132, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35880385

RESUMEN

COVID-19 causes more than million deaths worldwide. Although much is understood about the immunopathogenesis of the lung disease, a lot remains to be known on the neurological impact of COVID-19. Here, we evaluated immunometabolic changes using astrocytes in vitro and dissected brain areas of SARS-CoV-2 infected Syrian hamsters. We show that SARS-CoV-2 alters proteins of carbon metabolism, glycolysis, and synaptic transmission, many of which are altered in neurological diseases. Real-time respirometry evidenced hyperactivation of glycolysis, further confirmed by metabolomics, with intense consumption of glucose, pyruvate, glutamine, and alpha ketoglutarate. Consistent with glutamine reduction, the blockade of glutaminolysis impaired viral replication and inflammatory response in vitro. SARS-CoV-2 was detected in vivo in hippocampus, cortex, and olfactory bulb of intranasally infected animals. Our data evidence an imbalance in important metabolic molecules and neurotransmitters in infected astrocytes. We suggest this may correlate with the neurological impairment observed during COVID-19, as memory loss, confusion, and cognitive impairment.


Asunto(s)
COVID-19 , Animales , Astrocitos , Carbono , Cricetinae , Modelos Animales de Enfermedad , Glucosa , Glutamina , Ácidos Cetoglutáricos , Mesocricetus , Piruvatos , SARS-CoV-2
9.
Chem Rec ; 22(2): e202100215, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34669242

RESUMEN

The use of laccases applied in bioremediation processes has been increasingly studied, given the urgent need to overcome the environmental problems caused by emerging contaminants. It is known that immobilized enzymes have better operational stability under reaction conditions, allowing for greater applicability. However, given the lack of commercially available immobilized laccases, the search for immobilization materials and methods continues to gain effort. The use of polyacrylonitrile (PAN) to immobilize enzymes has been investigated since it is a low-cost material and can be modified and functionalized to well interact with the enzyme. This polymer can be used with different morphologies such as fibers, beads, and core-shell, presenting as an easily applicable alternative. This review presents the missing link between polymer and enzyme through an overview of PAN's current use as support for laccase immobilization and polymer functionalization methods, considering the importance of immobilized laccases in several industrial sectors.


Asunto(s)
Enzimas Inmovilizadas , Lacasa , Resinas Acrílicas , Biodegradación Ambiental
10.
Eur Radiol ; 32(6): 3889-3902, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35133484

RESUMEN

OBJECTIVE: The purpose of this study was to evaluate the prognostic value of novel geometric variables obtained from pre-treatment [18F]FDG PET/CT with respect to classical ones in patients with non-small cell lung cancer (NSCLC). METHODS: Retrospective study including stage I-III NSCLC patients with baseline [18F]FDG PET/CT. Clinical, histopathologic, and metabolic parameters were obtained. After tumor segmentation, SUV and volume-based variables, global texture, sphericity, and two novel parameters, normalized SUVpeak to centroid distance (nSCD) and normalized SUVmax to perimeter distance (nSPD), were obtained. Early recurrence (ER) and short-term mortality (STM) were used as end points. Univariate logistic regression and multivariate logistic regression with respect to ER and STM were performed. RESULTS: A cohort of 173 patients was selected. ER was detected in 49/104 of patients with recurrent disease. Additionally, 100 patients died and 53 had STM. Age, pathologic lymphovascular invasion, lymph nodal infiltration, TNM stage, nSCD, and nSPD were associated with ER, although only age (aOR = 1.06, p = 0.002), pathologic lymphovascular invasion (aOR = 3.40, p = 0.022), and nSPD (aOR = 0.02, p = 0.018) were significant independent predictors of ER in multivariate analysis. Age, lymph nodal infiltration, TNM stage, nSCD, and nSPD were predictors of STM. Age (aOR = 1.05, p = 0.006), lymph nodal infiltration (aOR = 2.72, p = 0.005), and nSPD (aOR = 0.03, p = 0.022) were significantly associated with STM in multivariate analysis. Coefficient of variation (COV) and SUVmean/SUVmax ratio did not show significant predictive value with respect to ER or STM. CONCLUSION: The geometric variables, nSCD and nSPD, are robust biomarkers of the poorest outcome prediction of patients with NSCLC with respect to classical PET variables. KEY POINTS: • In NSCLC patients, it is crucial to find prognostic parameters since TNM system alone cannot explain the variation in lung cancer survival. • Age, lymphovascular invasion, lymph nodal infiltration, and metabolic geometrical parameters were useful as prognostic parameters. • The displacement grade of the highest point of metabolic activity towards the periphery assessed by geometric variables obtained from [18F]FDG PET/CT was a robust biomarker of the poorest outcome prediction of patients with NSCLC.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Carcinoma de Pulmón de Células no Pequeñas/patología , Fluorodesoxiglucosa F18 , Humanos , Neoplasias Pulmonares/patología , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Tomografía de Emisión de Positrones , Pronóstico , Radiofármacos , Estudios Retrospectivos
12.
Exp Parasitol ; 241: 108345, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35985513

RESUMEN

Haemonchus contortus is a highly pathogenic and prevalent helminth that causes many deaths in sheep herds. Anthelmintics are usually employed to overcome this issue; however, they do not guarantee immediate and lasting efficacy because of the occurrence of drug-resistant parasites. Among substances that are used in scientific studies for parasitic control, essential oils are known to have different pharmacological properties. However, they demonstrate instability owing to several factors, and therefore, nanoemulsification is considered an alternative to control the instability and degradability of these compounds. The objective of this study was to evaluate the cytotoxicity of nanoemulsions containing essential oil of Eucalyptus globulus against the blood of healthy sheep and to verify their activity against the parasite H. contortus in sheep. The results presented adequate nanotechnological characteristics (diameter 72 nm, PDI 0.2, zeta -11 mV, and acidic pH) and adequate morphology. Further, the corona effect and cytotoxic profiles of the free oil and nanoemulsion against blood cells from healthy sheep were evaluated. The tests results did not present a toxicity profile. For evaluating efficacy, we observed an important anthelmintic action of the nanoemulsion containing oil in comparison to the free oil; the results demonstrate a potential role of the nanoemulsion in the inhibition of egg hatchability and the development of larvae L1 to L3 (infective stage). Based on these results, we developed an important and potential anthelmintic alternative for the control of the parasite H. contortus.


Asunto(s)
Antihelmínticos , Hemoncosis , Haemonchus , Aceites Volátiles , Enfermedades de las Ovejas , Animales , Antihelmínticos/uso terapéutico , Antihelmínticos/toxicidad , Aceite de Eucalipto/farmacología , Hemoncosis/tratamiento farmacológico , Hemoncosis/parasitología , Hemoncosis/veterinaria , Larva , Aceites Volátiles/química , Aceites Volátiles/toxicidad , Ovinos , Enfermedades de las Ovejas/tratamiento farmacológico , Enfermedades de las Ovejas/parasitología
13.
Rev Argent Microbiol ; 54(2): 95-99, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34083031

RESUMEN

Changes were made to the original formulation of the EMJH medium (Ellinghausen-McCullough-Johnson-Harris) enrichment and some aspects such as growth time of Leptospira and utilization in the microscopic agglutination test (MAT) were evaluated and compared to the original enrichment and to a commercially available enrichment (DIFCO™). Leptospira samples (24 antigens) that make up our panel of antigens used in MAT were used, among them, reference and autochthonous strains isolated in Brazil. The samples were grown individually in the EMJH medium under the three previously mentioned conditions (adapted enrichment, original enrichment and commercial enrichment). In addition, 89 blood serums from domestic and wild animals were analyzed by MAT using the antigens grown in these media. All samples tested grew efficiently with the adapted enrichment, and the MAT results were satisfactory. Therefore, other laboratories could also benefit from the use of this adapted enrichment when culturing the Leptospira strains applied in their MAT panels.


Asunto(s)
Leptospira , Leptospirosis , Animales , Animales Salvajes , Brasil , Leptospirosis/veterinaria
14.
BMC Microbiol ; 21(1): 99, 2021 03 31.
Artículo en Inglés | MEDLINE | ID: mdl-33789603

RESUMEN

BACKGROUND: Leptospirosis is a zoonotic disease caused by infection with spirochetes from Leptospira genus. It has been classified into at least 17 pathogenic species, with more than 250 serologic variants. This wide distribution may be a result of leptospiral ability to colonize the renal tubules of mammalian hosts, including humans, wildlife, and many domesticated animals. Previous studies showed that the expression of proteins belonging to the microbial heat shock protein (HSP) family is upregulated during infection and also during various stress stimuli. Several proteins of this family are known to have important roles in the infectious processes in other bacteria, but the role of HSPs in Leptospira spp. is poorly understood. In this study, we have evaluated the capacity of the protein GroEL, a member of HSP family, of interacting with host proteins and of stimulating the production of cytokines by macrophages. RESULTS: The binding experiments demonstrated that the recombinant GroEL protein showed interaction with several host components in a dose-dependent manner. It was also observed that GroEL is a surface protein, and it is secreted extracellularly. Moreover, two cytokines (tumor necrosis factor-α and interleukin-6) were produced when macrophages cells were stimulated with this protein. CONCLUSIONS: Our findings showed that GroEL protein may contribute to the adhesion of leptospires to host tissues and stimulate the production of proinflammatory cytokines during infection. These features might indicate an important role of GroEL in the pathogen-host interaction in the leptospirosis.


Asunto(s)
Chaperonina 60/inmunología , Citocinas/inmunología , Interacciones Huésped-Patógeno/inmunología , Leptospira/metabolismo , Macrófagos/inmunología , Macrófagos/microbiología
15.
Exp Parasitol ; 226-227: 108125, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34129877

RESUMEN

Chagas disease, caused by Trypanosoma cruzi, is a major public health problem and is described as one of the most neglected diseases worldwide. It affects about 6-7 million people. Currently, only two drugs are available for the treatment of this disease: nifurtimox and benznidazole. However, both drugs are highly toxic and have several side effects, which lead many patients to discontinue treatment. Moreover, these compounds show a significant curative efficacy only in the acute phase of the disease. Therefore, searching for new drugs is necessary. The objective of this study was to evaluate the in vitro and in vivo activity of a benzofuroxan derivative (EA2) against T. cruzi, and to evaluate the hematological and biochemical changes induced by its treatment in animals infected with T. cruzi. The results were then compared with those of healthy controls. In vitro testing was first performed with T. cruzi epimastigote forms. In this experiment, EA2 was diluted at three different concentrations (0.25, 0.50, and 1%). In vitro evaluation of the trypanocidal activity was performed 24, 48, and 72 h after incubation. In vivo assays were performed using three different doses (10, 5, and 2,5 mg/kg). Mice were divided into 10 groups (five animals/group), wherein four groups comprised non-infected animals (A, G, H, I) and six groups comprised infected animals (B, C, D E, F, J). Groups B and J represented the negative and positive controls, respectively. Groups G, H, and I were used to confirm that EA2 was not toxic to non-infected animals. Parasitemia was measured in infected animals and the hematological and biochemical profiles (urea, creatinine, albumin, aspartate aminotransferase, alanine aminotransferase, and alkaline phosphatase) were evaluated in all animals. EA2 demonstrated in vitro trypanocidal activity at all concentrations tested. Although it did not demonstrate a curative effect in vivo, EA2 was able to retard the onset of parasitemia, and significantly reduced the parasite count in groups D and E (treated with 5 and 2.5 mg/kg, respectively). EA2 did not induce changes in hematological and biochemical parameters in non-infected animals, demonstrating that it is not toxic. However, further assessments should aim to confirm the safety of EA2 since this was the first in vitro and in vivo study conducted with this molecule.


Asunto(s)
Benzofuranos/uso terapéutico , Enfermedad de Chagas/tratamiento farmacológico , Parasitemia/tratamiento farmacológico , Tripanocidas/uso terapéutico , Trypanosoma cruzi/efectos de los fármacos , Animales , Benzofuranos/farmacología , Análisis Químico de la Sangre , Enfermedad de Chagas/sangre , Recuento de Eritrocitos , Femenino , Hemoglobinas/análisis , Ratones , Parasitemia/sangre , Recuento de Plaquetas , Distribución Aleatoria , Tripanocidas/farmacología , Trypanosoma cruzi/crecimiento & desarrollo
16.
Trop Anim Health Prod ; 53(2): 194, 2021 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-33666800

RESUMEN

At present, little is known regarding the prevalence of buffalo leptospirosis worldwide, especially with respect to which Leptospira strains may infect this animal species. Furthermore, most investigations into this disease in buffaloes have only been performed with serological studies. In Brazil, particularly in the Amazon, buffalo production is growing and is just as important as cattle production, although few studies have been performed on buffalo compared to cattle. Thus, the aim of this study was to isolate and characterise Leptospira strains from river buffaloes raised in the Brazilian Amazon region. We collected 109 kidney samples from slaughtered buffaloes raised in the Amazon Delta region of Brazil. The samples were analysed by bacteriological culture for the isolation of leptospires, and the obtained isolates were serologically and molecularly characterised by microscopic agglutination test (MAT), DNA sequencing and multiple locus variable-number tandem repeat analysis (MLVA). Five isolates were obtained, and in serogrouping analyses, these isolates were only reactive for the Pomona serogroup, with an observed titre of 25,600. The DNA sequencing results revealed that all the isolates belonged to the species Leptospira interrogans, and the MLVA results showed that the VNTR loci 4, 7 and 10 profile of all the isolates was 4-1-10. In this study, we observed that Pomona serogroup strains circulate in buffaloes in the Amazon, showing that in Brazil, buffaloes can be affected by Leptospira strains other than the Sejroe group, which are adapted to cattle.


Asunto(s)
Búfalos/microbiología , Leptospira interrogans/clasificación , Leptospira interrogans/aislamiento & purificación , Leptospirosis/veterinaria , Ríos , Animales , Brasil/epidemiología , Femenino , Leptospira interrogans/genética , Leptospirosis/epidemiología , Masculino
17.
J Vet Med Educ ; 48(6): 649-655, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33226900

RESUMEN

This article aims to standardize 3D scanning and printing of dog skulls for educational use and evaluate the effectiveness of these anatomical printed models for a veterinary anatomy course. Skulls were selected for scanning and creating 3D-printed models through Fused Deposition Modeling using acrylonitrile-butadiene-styrene. After a lecture on skull anatomy, the 3D-printed and real skull models were introduced during the practical bone class to 140 students. A bone anatomy practical test was conducted after a month; it consisted in identifying previously marked anatomical structures of the skull bones. The students were divided into two groups for the exam; the first group of students took the test on the real skulls, whereas the second group of students took the test on 3D-printed skulls. The students' performance was evaluated using similar practical examination questions. At the end of the course, these students were asked to answer a brief questionnaire about their individual experiences. The results showed that the anatomical structures of the 3D-printed skulls were similar to the real skulls. There was no significant difference between the test scores of the students that did their test using the real skulls and those using 3D prints. In conclusion, it was possible to construct a dynamic and printed digital 3D collection for studies of the comparative anatomy of canine skull species from real skulls, suggesting that 3D-digitalized and-printed skulls can be used as tools in veterinary anatomy teaching.


Asunto(s)
Educación en Veterinaria , Animales , Perros , Evaluación Educacional , Imagenología Tridimensional , Impresión Tridimensional , Cráneo
18.
Glia ; 68(12): 2705-2724, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32645245

RESUMEN

Glaucoma is a degenerative disease that causes irreversible loss of vision and is characterized by retinal ganglion cell (RGC) loss. Others and we have demonstrated that chronic neuroinflammation mediated by reactive microglial cells plays a role in glaucomatous pathology. Exosomes are extracellular vesicles released by most cells, including microglia, that mediate intercellular communication. The role of microglial exosomes in glaucomatous degeneration remains unknown. Taking the prominent role of microglial exosomes in brain neurodegenerative diseases, we studied the contribution of microglial-derived exosomes to the inflammatory response in experimental glaucoma. Microglial cells were exposed to elevated hydrostatic pressure (EHP), to mimic elevated intraocular pressure, the main risk factor for glaucoma. Naïve microglia (BV-2 cells or retinal microglia) were exposed to exosomes derived from BV-2 cells under EHP conditions (BV-Exo-EHP) or cultured in control pressure (BV-Exo-Control). We found that BV-Exo-EHP increased the production of pro-inflammatory cytokines, promoted retinal microglia motility, phagocytic efficiency, and proliferation. Furthermore, the incubation of primary retinal neural cell cultures with BV-Exo-EHP increased cell death and the production of reactive oxygen species. Exosomes derived from retinal microglia (MG-Exo-Control or MG-Exo-EHP) were injected in the vitreous of C57BL/6J mice. MG-Exo-EHP sustained activation of retinal microglia, mediated cell death, and impacted RGC number. Herein, we show that exosomes derived from retinal microglia have an autocrine function and propagate the inflammatory signal in conditions of elevated pressure, contributing to retinal degeneration in glaucomatous conditions.


Asunto(s)
Exosomas , Glaucoma , Animales , Inflamación , Ratones , Ratones Endogámicos C57BL , Microglía , Células Ganglionares de la Retina
19.
Exp Eye Res ; 199: 108195, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32841650

RESUMEN

Increasing evidence points to inflammation as a key factor in the pathogenesis of diabetic retinopathy (DR). Choroidal inflammatory changes in diabetes have been reported and in vivo choroidal thickness (CT) has been searched as a marker of retinopathy with contradictory results. We aimed to investigate the early stages in the retina and choroid in an animal model of Type 1 diabetes. Type 1 diabetes was induced in male Wistar rats via a single i.p. streptozotocin injection. At 8 weeks after disease onset, CT, choroidal vascular density, VEGF and VEGFR2 expression, microglial cell and pericyte distribution were evaluated. Diabetic rats showed no significant change in CT and choroidal vascular density. A widened pericyte-free gap between the retinal pigment epithelium and the choroid was observed in diabetic rats. The immunoreactivity of VEGFR2 was decreased in the retina of diabetic rats, despite no statistically significant difference in the immunoreactivity of VEGF. The density of microglial cells significantly increased in the choroid and retina of diabetic rats. Reactive microglial cells were found to be more abundant in the choroid of diabetic rats. Evidences of the interconnection between the superficial, intermediate, and deep plexuses of the retina were also observed. At early stages, Type 1 diabetes does not affect choroidal thickness and choroidal vascular density. Proliferation and reactivity of microglial cells occurs in the choroidal stroma and the retina. The expression of VEGFR2 decreases in the retina.


Asunto(s)
Coroides/patología , Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 1/patología , Retinopatía Diabética/patología , Retina/patología , Animales , Proliferación Celular , Progresión de la Enfermedad , Angiografía con Fluoresceína/métodos , Fondo de Ojo , Masculino , Ratas , Ratas Wistar
20.
Int J Mol Sci ; 21(19)2020 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-33007835

RESUMEN

Glaucoma is a progressive chronic retinal degenerative disease and a leading cause of global irreversible blindness, characterized by optic nerve damage and retinal ganglion cell (RGC) death. Elevated intraocular pressure (IOP) is a main risk factor of glaucoma. Neuroinflammation plays an important role in glaucoma. We have been demonstrating that elevated pressure triggers microglia reactivity that contribute to the loss of RGCs. Adenosine, acting on adenosine receptors, is a crucial modulator of microglia phenotype. Microglia express all adenosine receptors. Previously, we demonstrated that the activation of adenosine A3 receptor (A3R) affords protection to the retina, including RGCs, unveiling the possibility for a new strategy for glaucoma treatment. Since microglial cells express A3R, we now studied the ability of a selective A3R agonist (2-Cl-IB-MECA) in controlling microglia reactivity induced by elevated hydrostatic pressure (EHP), used to mimic elevated IOP. The activation of A3R reduced EHP-induced inducible nitric oxide synthase (iNOS) expression, microglia migration and phagocytosis in BV-2 cells. In retinal microglia, proliferation and phagocytosis elicited by EHP were also decreased by A3R activation. This work demonstrates that 2-Cl-IB-MECA, the selective agonist of A3R, is able to hinder microglia reactivity, suggesting that A3R agonists could afford protection against glaucomatous degeneration through the control of neuroinflammation.


Asunto(s)
Agonistas del Receptor de Adenosina A3/farmacología , Adenosina/análogos & derivados , Glaucoma/tratamiento farmacológico , Receptor de Adenosina A3/genética , Adenosina/genética , Adenosina/farmacología , Animales , Muerte Celular/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Glaucoma/genética , Glaucoma/patología , Humanos , Presión Intraocular/efectos de los fármacos , Microglía/efectos de los fármacos , Nervio Óptico/efectos de los fármacos , Nervio Óptico/patología , Traumatismos del Nervio Óptico/tratamiento farmacológico , Traumatismos del Nervio Óptico/genética , Traumatismos del Nervio Óptico/patología , Fagocitosis/efectos de los fármacos , Ratas , Degeneración Retiniana/tratamiento farmacológico , Degeneración Retiniana/genética , Degeneración Retiniana/patología , Células Ganglionares de la Retina/efectos de los fármacos , Células Ganglionares de la Retina/patología
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