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1.
J Environ Manage ; 368: 122141, 2024 Sep.
Article de Anglais | MEDLINE | ID: mdl-39128345

RÉSUMÉ

Microalgae have emerged as a promising source of biomass to produce renewable biofuels due to their ability to synthesize high-energy density compounds of commercial interest. This study proposes an approach for pilot-scale oil extraction, purification by fractional distillation, hydrocarbon characterization by gas chromatography coupled to mass spectrometry (GC-MS), evaluation of physicochemical parameters of the produced hydrocarbons, preliminary cost analysis, and challenges and future opportunities for green diesel on a commercial scale. Here, the microalgae Tetradesmus obliquus was cultivated in 12 m³ photobioreactors using biodigested swine waste as a culture medium. The resulting biomass was subjected to drying and harvesting, followed by oil extraction using a hot solvent extraction method, followed by distillation to purify the compounds. Three different extraction and distillation experiments were conducted, each using different solvent combinations. The results obtained revealed that extraction with a solvent blend, composed of hexane and ethanol, provided more significant yields compared to extraction with pure hexane. GC-MS analysis showed the presence of alkanes and alkenes in the oil samples, and the proportion of solvent used in the extraction directly influenced the production of alkanes. Additionally, specific hydrocarbons such as 4-methyl-1-decene, 8-heptadecene, 1-pentadecene, 9-heneicosene, and 2-dodecene were identified. The evaluation of the physicochemical parameters demonstrated that the calorific value of the distilled oil samples is within the range of typical values for petroleum diesel. However, it was observed that the distilled oil samples had higher sulfur content compared to conventional diesel. Regarding the cost analysis, it was found that it varies depending on the experimental conditions. In particular, the process using a solvent mixture of 70% hexane and 30% ethanol proved to be more economical than the others, since it extracted a greater quantity of oil with a lower initial biomass requirement. In summary, this microalgae-derived hydrocarbon production process is promising and offers insights for compound purification and future biofuel applications.


Sujet(s)
Biocarburants , Biomasse , Microalgues , Microalgues/métabolisme , Chromatographie gazeuse-spectrométrie de masse , Animaux , Essence , Solvants/composition chimique
2.
Sci Rep ; 14(1): 17332, 2024 07 27.
Article de Anglais | MEDLINE | ID: mdl-39068167

RÉSUMÉ

Senescent cells have been linked to the pathogenesis of metabolic dysfunction-associated steatotic liver disease (MASLD). However, the effectiveness of senolytic drugs in reducing liver damage in mice with MASLD is not clear. Additionally, MASLD has been reported to adversely affect male reproductive function. Therefore, this study aimed to evaluate the protective effect of senolytic drugs on liver damage and fertility in male mice with MASLD. Three-month-old male mice were fed a standard diet (SD) or a choline-deficient western diet (WD) until 9 months of age. At 6 months of age mice were randomized within dietary treatment groups into senolytic (dasatinib + quercetin [D + Q]; fisetin [FIS]) or vehicle control treatment groups. We found that mice fed choline-deficient WD had liver damage characteristic of MASLD, with increased liver size, triglycerides accumulation, fibrosis, along increased liver cellular senescence and liver and systemic inflammation. Senolytics were not able to reduce liver damage, senescence and systemic inflammation, suggesting limited efficacy in controlling WD-induced liver damage. Sperm quality and fertility remained unchanged in mice developing MASLD or receiving senolytics. Our data suggest that liver damage and senescence in mice developing MASLD is not reversible by the use of senolytics. Additionally, neither MASLD nor senolytics affected fertility in male mice.


Sujet(s)
Fécondité , Flavonols , Quercétine , Sénothérapie , Animaux , Mâle , Souris , Fécondité/effets des médicaments et des substances chimiques , Quercétine/pharmacologie , Sénothérapie/pharmacologie , Flavonols/pharmacologie , Foie/métabolisme , Foie/effets des médicaments et des substances chimiques , Foie/anatomopathologie , Vieillissement de la cellule/effets des médicaments et des substances chimiques , Stéatose hépatique/traitement médicamenteux , Stéatose hépatique/métabolisme , Stéatose hépatique/anatomopathologie , Régime occidental/effets indésirables , Évolution de la maladie , Carence en choline/complications , Souris de lignée C57BL , Modèles animaux de maladie humaine
3.
J Cardiothorac Surg ; 19(1): 323, 2024 Jun 07.
Article de Anglais | MEDLINE | ID: mdl-38849906

RÉSUMÉ

BACKGROUND: Marfan Syndrome is an autosomal dominant disease caused by pathogenetic variants in the FBN1 gene. The progressive dilatation of the aorta and the potential risk of acute aortic syndromes influence the prognosis of these patients. We aim to describe population characteristics, long-term survival, and re-intervention patterns in patients who underwent aortic surgery with a previously confirmed clinical diagnosis of Marfan Syndrome in a middle-income country. METHODS: A retrospective single-center case series study was conducted. All Marfan Syndrome patients who underwent aortic procedures from 2004 until 2021 were included. Qualitative variables were frequency-presented, while quantitative ones adopted mean ± standard deviation. A subgroup analysis between elective and emergent procedures was conducted. Kaplan-Meier plots depicted cumulative survival and re-intervention-free. Control appointments and government data tracked out-of-hospital mortality. RESULTS: Fifty patients were identified. The mean age was 38.79 ± 14.41 years, with a male-to-female ratio of 2:1. Common comorbidities included aortic valve regurgitation (66%) and hypertension (50%). Aortic aneurysms were observed in 64% without dissection and 36% with dissection. Surgical procedures comprised elective (52%) and emergent cases (48%). The most common surgery performed was the David procedure (64%), and the Bentall procedure (14%). The in-hospital mortality rate was 4%. Complications included stroke (10%), and acute kidney injury (6%). The average follow-up was 8.88 ± 5.78 years. Survival rates at 5, 10, and 15 years were 89%, 73%, and 68%, respectively. Reintervention rates at 1, 2.5, and 5 years were 10%, 14%, and 17%, respectively. The emergent subgroup was younger (37.58 ± 14.49 years), had the largest number of Stanford A aortic dissections, presented hemodynamic instability (41.67%), and had a higher requirement of reinterventions in the first 5 years of follow-up (p = 0.030). CONCLUSION: In our study, surveillance programs played a pivotal role in sustaining high survival rates and identifying re-intervention requirements. However, challenges persist, as 48% of the patients required emergent surgery. Despite not affecting survival rates, a greater requirement for reinterventions was observed, emphasizing the necessity of timely diagnosis. Enhanced educational initiatives for healthcare providers and increased patient involvement in follow-up programs are imperative to address these concerns.


Sujet(s)
Syndrome de Marfan , Humains , Syndrome de Marfan/complications , Syndrome de Marfan/chirurgie , Mâle , Femelle , Études rétrospectives , Adulte , Adulte d'âge moyen , 795/chirurgie , Jeune adulte , Anévrysme de l'aorte/chirurgie
4.
Cir Cir ; 92(2): 255-263, 2024.
Article de Anglais | MEDLINE | ID: mdl-38782388

RÉSUMÉ

OBJECTIVE: To assess and compare the functional and quality of life results in patients treated with curative intent for localized prostate cancer during 2015 in our hospital. METHOD: 77 patients treated by radical prostatectomy or external radiotherapy with androgen deprivation were prospective enrolled. Expanded Prostate Cancer Index Composite for Clinical Practice (EPIC-CP) questionnaire at 3-year follow-up and Spanish Questionnaire on Quality of Life in Patients with Prostate Cancer (CAVIPRES-30) at diagnosis and at 3-year follow-up were registered. RESULTS: 68 patients were included, 39 patients treated by radical prostatectomy and 29 received external radiotherapy with androgen deprivation. Among the operated patients, 61.5% were dry and 17.9% use three or more daily pads, compared to 72.4% and 6.8%, respectively, in the radiotherapy group. 48.7% of prostatectomized patients reported very poor or no capacity to have a sufficiently rigid erection, compared to 69% of the radiated group. After surgery, 43.6% considered bad or very bad quality-of-life, compared to 68.9% in the radiotherapy group. In the comparison of the data of the pre- and post-treatment questionnaire can be seen that the patients had a superior perception before the procedure. CONCLUSIONS: Patients treated by surgery have a better perception of quality-of-life compared to those treated by radiotherapy.


OBJETIVO: Determinar y comparar los resultados funcionales y de calidad de vida de pacientes con cáncer de próstata tratados con intención curativa durante el año 2015 en nuestro centro. MÉTODO: Se incluyeron 77 pacientes sometidos a prostatectomía radical (PR) o radioterapia externa con terapia de deprivación androgénica (TDA). Se realizaron el Expanded Prostate Cancer Index Composite for Clinical Practice (EPIC-CP) tras 3 años de seguimiento y el Cuestionario Español de Calidad de Vida en Pacientes con Cáncer de Próstata (CAVIPRES-30) al diagnóstico y a los 3 años. RESULTADOS: Se incluyeron 68 pacientes, 39 con PR y 29 con radioterapia más TDA. De los pacientes intervenidos, el 61.5% están secos y el 17.9% usan tres o más compresas, diarias frente al 72.4% y el 6.8%, respectivamente, en el grupo de radioterapia. El 48.7% de los prostatectomizados refieren erecciones muy malas o ninguna, frente al 69% de los radiados. Tras la cirugía, el 43.6% refieren mala o muy mala calidad de vida, frente al 68.9% de los radiados. En la comparación de los datos del cuestionario pre- y postratamiento, los pacientes tenían una percepción superior antes del procedimiento. CONCLUSIONES: Los pacientes tratados mediante cirugía tienen una mejor percepción de su calidad de vida relacionada con la salud que los radiados.


Sujet(s)
Prostatectomie , Tumeurs de la prostate , Qualité de vie , Humains , Mâle , Prostatectomie/méthodes , Tumeurs de la prostate/radiothérapie , Tumeurs de la prostate/chirurgie , Tumeurs de la prostate/psychologie , Sujet âgé , Études prospectives , Adulte d'âge moyen , Antagonistes des androgènes/usage thérapeutique , Enquêtes et questionnaires , Dysfonctionnement érectile/étiologie , Études de suivi
5.
Geroscience ; 46(3): 3445-3455, 2024 06.
Article de Anglais | MEDLINE | ID: mdl-38358579

RÉSUMÉ

Senescent cell number increases with age in different tissues, leading to greater senescent cell load, proinflammatory stress, and tissue dysfunction. In the current study, we tested the efficacy of senolytic drugs to reduce ovarian senescence and improve fertility in reproductive age female mice. In the first experiment, 1-month-old C57BL/6 female mice were treated every other week with D + Q (n = 24) or placebo (n = 24). At 3 and 6 months of age, female mice were mated with untreated males to evaluate pregnancy rate and litter size. In the second experiment, 6-month-old C57BL/6 female mice were treated monthly with D + Q (n = 30), fisetin (n = 30), or placebo (n = 30). Females were treated once a month until 11 months of age, then they were mated with untreated males for 30 days to evaluate pregnancy rate and litter size. In the first experiment, D + Q treatment did not affect pregnancy rate (P = 0.68), litter size (P = 0.58), or ovarian reserve (P > 0.05). Lipofuscin staining was lower in females treated with D + Q (P = 0.04), but expression of senescence genes in ovaries was similar. In the second experiment, D + Q or fisetin treatment also did not affect pregnancy rate (P = 0.37), litter size (P = 0.20), or ovarian reserve (P > 0.05). Lipofuscin staining (P = 0.008) and macrophage infiltration (P = 0.002) was lower in fisetin treated females. Overall, treatment with D + Q or fisetin did not affect ovarian reserve or fertility but did decrease some senescence markers in the ovary.


Sujet(s)
Réserve ovarienne , Grossesse , Mâle , Souris , Femelle , Animaux , Sénothérapie , Lipofuscine , Souris de lignée C57BL , Fécondité
6.
Reprod Biol ; 24(1): 100856, 2024 Mar.
Article de Anglais | MEDLINE | ID: mdl-38295721

RÉSUMÉ

Calorie restriction (CR) is an intervention that promotes longevity and preserves the ovarian reserve. Some studies have observed that the positive impacts of CR can be linked to restriction of protein (PR) and branched-chain amino acids (BCAAs) independent of calorie intake. The aim of this study was to compare the effects of protein and BCAA restriction to 30% CR on the ovarian reserve of female mice. For this, 3 month-old C57BL/6 female mice (n = 35) were randomized into four groups for four months dietary interventions including: control group (CTL; n = 8), 30% CR (CR; n = 9), protein restriction (PR; n = 9) and BCAA restriction (BCAAR; n = 9). Body mass gain, body composition, food intake, serum levels of BCAAs, ovarian reserve and estrous cyclicity were evaluated. We observed that CR, protein and BCAA restriction prevented weight gain and changed body composition compared to the CTL group. The BCAA restriction did not affect the ovarian reserve, while both PR and CR prevented activation of primordial follicles. This prevention occurred in PR group despite the lack of reduction of calorie intake compared to CTL group, and CR did not reduce protein intake in levels similar to the PR group. BCAA restriction resulted in increased calorie intake compared to CTL and PR mice, but only PR reduced serum BCAA levels compared to the CTL group. Our data indicates that PR has similar effects to CR on the ovarian reserve, whereas BCAA restriction alone did not affect it.


Sujet(s)
Restriction calorique , Ration calorique , Souris , Femelle , Animaux , Souris de lignée C57BL , Vieillissement , Acides aminés à chaine ramifiée/métabolisme
7.
J Vet Dent ; 41(3): 197-209, 2024 May.
Article de Anglais | MEDLINE | ID: mdl-37401331

RÉSUMÉ

Tooth enamel thickness is widely studied in primates and is important in differentiating taxa and in interpreting diet and feeding behavior. The objective of this study was to measure enamel thickness and discuss whether the results can be associated with different feeding patterns. Thirty-four syncraniums of Alouatta guariba clamitans, Alouatta caraya, and Sapajus nigritus were subjected to cone beam computed tomographic (CBCT) scans, and the dental enamel was measured in different regions of the crown using the multiplanar reconstruction tool. The differences observed indicate that for many variables and teeth, A. guariba clamitans showed significantly higher values compared to the other 2 species, with the exception of the cuspid region. Although the A. guariba clamitans is a folivorous species, it showed thicker enamel for most of the variables. CBCT was efficient in performing the measurements, allowing analysis of the syncraniums.


Sujet(s)
Alouatta caraya , Alouatta , Sapajus , Animaux , Tomodensitométrie à faisceau conique/médecine vétérinaire , Émail dentaire/imagerie diagnostique
8.
J Basic Microbiol ; 64(1): 94-105, 2024 Jan.
Article de Anglais | MEDLINE | ID: mdl-37696778

RÉSUMÉ

The current study examined the impact of ultraviolet (UV)-B radiation in Metarhizium pingshaense blastospores' photolyase expression and their virulence against Rhipicephalus microplus. Blastospores were exposed to UV under laboratory and field conditions. Ticks were treated topically with fungal suspension and exposed to UV-B in the laboratory for three consecutive days. The expression of cyclobutane pyrimidine dimmers (CPDs)-photolyase gene maphr1-2 in blastospores after UV exposure followed by white light exposure was accessed after 0, 8, 12, 24, 36, and 48 h. Average relative germination of blastospores 24 h after in vitro UV exposure was 8.4% lower than 48 h. Despite this, the relative germination of blastospores exposed to UV in the field 18 h (95.7 ± 0.3%) and 28 h (97.3 ± 0.8%) after exposure were not different (p > 0.05). Ticks treated with fungus and not exposed to UV exhibited 0% survival 10 days after the treatment, while fungus-treated ticks exposed to UV exhibited 50 ± 11.2% survival. Expression levels of maphr1-2 8, 12, and 24 h after UV-B exposure were not different from time zero. Maphr1-2 expression peak in M. pingshaense blastospores occurred 36 h after UV-B exposure, in the proposed conditions and times analyzed, suggesting repair mechanisms other than CPD-mediated-photoreactivation might be leading blastospores' germination from 0 to 24 h.


Sujet(s)
Deoxyribodipyrimidine photo-lyase , Metarhizium , Rhipicephalus , Animaux , Rhipicephalus/métabolisme , Rhipicephalus/microbiologie , Deoxyribodipyrimidine photo-lyase/génétique , Deoxyribodipyrimidine photo-lyase/métabolisme , Virulence , Lumière , Rayons ultraviolets , Metarhizium/métabolisme , Lutte biologique contre les nuisibles
9.
Vaccines (Basel) ; 11(10)2023 Sep 26.
Article de Anglais | MEDLINE | ID: mdl-37896930

RÉSUMÉ

During the COVID-19 pandemic, the importance of vaccinating children against SARS-CoV-2 was rapidly established. This study describes the safety of CoronaVac® in children and adolescents between 3- and 17-years-old in a multicenter study in Chile with two vaccine doses in a 4-week interval. For all participants, immediate adverse events (AEs), serious AEs (SAEs), and AEs of special interest (AESIs) were registered throughout the study. In the safety subgroup, AEs were recorded 28 days after each dose. COVID-19 surveillance was performed throughout the study. A total of 1139 individuals received the first and 1102 the second dose of CoronaVac®; 835 were in the safety subgroup. The first dose showed the highest number of AEs: up to 22.2% of participants reported any local and 17.1% systemic AE. AEs were more frequent in adolescents after the first dose, were transient, and mainly mild. Pain at the inoculation site was the most frequent AE for all ages. Fever was the most frequent systemic AE for 3-5 years old and headache in 6-17 years old. No SAEs or AESIs related to vaccination occurred. Most of the COVID-19 cases were mild and managed as outpatients. CoronaVac® was safe and well tolerated in children and adolescents, with different safety patterns according to age.

10.
An Acad Bras Cienc ; 95(suppl 3): e20210528, 2023.
Article de Anglais | MEDLINE | ID: mdl-37820118

RÉSUMÉ

The impact of the Antarctic Ozone Hole Influence over Southern Brazil in October 2015 was analyzed using daily mean data of the Total Column Ozone (TCO), Ultraviolet Index (UVI) and Radiative Cloud Fraction (RCF) from the Ozone Monitoring Instrument satellite instrument. Vertical profiles and fields of ozone content and Potential Vorticity available from the European Centre for Medium-Range Weather Forecast reanalysis, air masses backward trajectories from the HYbrid Single-Particle Lagrangian Integrated Trajectory model and channel 3 water vapor images from the Geostationary Operational Environmental Satellite GOES-13 were also analyzed. The five identified events showed an -7.4±2.3% average TCO reduction, leading to an +16.6±54.6% UVI increase even with a predominance of partly cloudy days. Other impacts were observed in the ozone profiles, where the most significant anomalies occurred from 650 K reaching 1.2 ppmv at the 850 K level. In the ozone fields at 700 K, the presence of a polar origin tongue was observed causing negatives anomalies between -0.2 and 0.4 ppmv in a transient system format forced with eastward-traveling Rossby waves passing through the Southern of Brazil and Uruguay.


Sujet(s)
Appauvrissement en ozone , Ozone , Brésil , Temps (météorologie) , Régions antarctiques
12.
Endocr Oncol ; 3(1): e220091, 2023 Jan 01.
Article de Anglais | MEDLINE | ID: mdl-37529773

RÉSUMÉ

Pheochromocytoma and paragangliomas (PPGLs) are rare neuroendocrine tumors carrying 25-40% pathogenic germline gene variants (PGVs). We evaluated clinical, laboratory, and germline molecular profile of 115 patients with pathologic (14 patients were relatives from 8 different families recruited for genetic survey) confirmed PPGL followed in our institution. Patients with classic MEN2A/MEN2B phenotypes and at-risk relatives underwent direct analysis of RET proto-oncogene, and the remaining had samples submitted to complete next-generation sequencing aiming 23 PPGL-related genes: ATM, ATR, CDKN2A, EGLN1, FH, HRAS, KIF1B, KMT2D, MAX, MDH2, MERTK, MET, NF1, PIK3CA, RET, SDHA, SDHAF2, SDHB, SDHC, SDHD, TMEM127, TP53, and VHL. We also developed a clinical judgment score (CJS) to determine the probability of patients having a potentially hereditary disease. The resulting genetic landscape showed that 67 patients (58.3%) had variants in at least one gene: 34 (50.7%) had exclusively pathogenic or likely pathogenic variants, 13 (19.4%) had pathogenic or likely pathogenic variants and variant of undetermined significance (VUS), and 20 (29.8%) carried only VUS. PGVs were found in RET (n = 18; 38.3%), VHL (n = 10; 21.3%), SDHB and NF1 (n = 8; 17% each), and MAX, SDHD, TMEM127, and TP53 (n = 1; 2.1% each). Direct genetic testing disclosed 91.3% sensitivity, 81.2% specificity, and 76.4% and 93.3% positive predictive value (PPV) and negative predictive values (NPV), respectively. The CJS to identify patients who would not benefit from genetic testing had 75% sensitivity, 96.4% specificity, and 60% and 98.2% PPV and NPV, respectively. In summary, the landscape of PPGL germline gene variants from 115 Brazilian patients resulted in slightly higher prevalent pathogenic and likely pathogenic variants, especially in the RET gene. We suggest a CJS to identify PPGL patients who would not require initial genetic evaluation, improving test specificity and reducing costs.

13.
Sensors (Basel) ; 23(16)2023 Aug 16.
Article de Anglais | MEDLINE | ID: mdl-37631747

RÉSUMÉ

Developing a low-cost wireless energy meter with power quality measurements for smart grid applications represents a significant advance in efficient and accurate electric energy monitoring. In increasingly complex and interconnected electric systems, this device will be essential for a wide range of applications, such as smart grids, by introducing a real-time energy monitoring system. In light of this, smart meters can offer greater opportunities for sustainable and efficient energy use and improve the utilization of energy sources, especially those that are nonrenewable. According to the 2020 International Energy Agency (IEA) report, nonrenewable energy sources represent 65% of the global supply chain. The smart meter developed in this work is based on the ESP32 microcontroller and easily accessible components since it includes a user-friendly development platform that offers a cost-effective solution while ensuring reliable performance. The main objective of developing the smart meters was to enhance the software and simplify the hardware. Unlike traditional meters that calculate electrical parameters by means of complex circuits in hardware, this project performed the calculations directly on the microcontroller. This procedure reduced the complexity of the hardware by simplifying the meter design. Owing to the high-performance processing capability of the microcontroller, efficient and accurate calculations of electrical parameters could be achieved without the need for additional circuits. This software-driven approach with simplified hardware led to benefits, such as reduced production costs, lower energy consumption, and a meter with improved accuracy, as well as updates on flexibility. Furthermore, the integrated wireless connectivity in the microcontroller enables the collected data to be transmitted to remote monitoring systems for later analysis. The innovative feature of this smart meter lies in the fact that it has readily available components, along with the ESP32 chip, which results in a low-cost smart meter with performance that is comparable to other meters available on the market. Moreover, it is has the capacity to incorporate IoT and artificial intelligence applications. The developed smart meter is cost effective and energy efficient, and offers benefits with regard to flexibility, and thus represents an innovative, efficient, and versatile solution for smart grid applications.

14.
Auton Neurosci ; 248: 103107, 2023 09.
Article de Anglais | MEDLINE | ID: mdl-37454409

RÉSUMÉ

Previous studies from our laboratory have shown that the pressor response to intracerebroventricular (icv) administered ANG II in normotensive rats or spontaneously hypertensive rats (SHRs) is attenuated by increased central H2O2 concentration, produced either by direct H2O2 icv injection or by increased endogenous H2O2 centrally in response to local catalase inhibition with 3-amino-1,2,4-triazole (ATZ). In the present study, we evaluated the effects of ATZ administered peripherally on arterial pressure and sympathetic and angiotensinergic activity in SHRs. Male SHRs weighing 280-330 g were used. Mean arterial pressure (MAP) and heart rate (HR) were recorded in conscious freely moving SHRs. Acute intravenous injection of ATZ (300 mg/kg of body weight) did not modify MAP and HR during the next 4 h, however, the treatment with ATZ (300 mg/kg of body weight twice per day) for 3 days reduced MAP (144 ± 6, vs. saline, 183 ± 13 mmHg), without changing HR. Intravenous hexamethonium (ganglionic blocker) produced a smaller decrease in MAP 4 h after ATZ (-25 ± 3, vs saline -38 ± 4 mmHg). Losartan (angiotensinergic AT1 receptor blocker) produced a significant depressor response 4 h after ATZ (-22 ± 4, vs. saline: -2 ± 4 mmHg) and in 3-day ATZ treated SHRs (-25 ± 5, vs. saline: -9 ± 4 mmHg). The results suggest that the treatment with ATZ reduces sympathetic activity in SHRs and simultaneously increases angiotensinergic activity.


Sujet(s)
Hypertension artérielle , Triazoles , Rats , Mâle , Animaux , Rats de lignée SHR , Amitrole/pharmacologie , Triazoles/pharmacologie , Peroxyde d'hydrogène/pharmacologie , Pression sanguine , Rythme cardiaque , Poids , Hypertension artérielle/traitement médicamenteux
15.
An Acad Bras Cienc ; 95(2): e20220420, 2023.
Article de Anglais | MEDLINE | ID: mdl-37341273

RÉSUMÉ

Masonry retaining walls are designed to resist lateral forces. Their stability is essentially warranted by the correct determination of the failure surface geometry. Accordingly, this study intended to investigate the influence of wall and backfill properties that control failure surface geometry of cohesionless backfills. For this purpose, the discrete element method (DEM) is utilized, and a series of parametric studies were conducted. As the wall-joint parameters reflect the mortar quality of the blocks that constitute the masonry wall, three binder types from weak to strong were defined. Additionally, loose to dense backfill soil conditions and wall-backfill interface properties were also investigated. The results indicate that in the case of a thin rigid wall, the failure surface of dense backfill is identical with the classical earth pressure theory. However, for the masonry walls with a higher foundation width, the failure surfaces are much deeper and wider; particularly on the active side compared to the classical earth pressure theories. In addition to that the deformation mechanism and the associated failure surfaces are greatly influenced from the mortar quality which results with either a deep-seated or sliding type of failure.

16.
Physiol Int ; 110(2): 121-134, 2023 Jun 12.
Article de Anglais | MEDLINE | ID: mdl-37235453

RÉSUMÉ

Cellular senescence is a defense mechanism to arrest proliferation of damaged cells. The number of senescent cells increases with age in different tissues and contributes to the development of age-related diseases. Old mice treated with senolytics drugs, dasatinib and quercetin (D+Q), have reduced senescent cells burden. The aim of this study was to evaluate the effects of D+Q on testicular function and fertility of male mice. Mice (n = 9/group) received D (5 mg kg-1) and Q (50 mg kg-1) via gavage every moth for three consecutive days from 3 to 8 months of age. At 8 months mice were breed with young non-treated females and euthanized. The treatment of male mice with D+Q increased serum testosterone levels and sperm concentration and decreased abnormal sperm morphology. Sperm motility, seminiferous tubule morphometry, testicular gene expression and fertility were not affected by treatment. There was no effect of D+Q treatment in ß-galactosidase activity and in lipofuscin staining in testes. D+Q treatment also did not affect body mass gain and testes mass. In conclusion, D+Q treatment increased serum testosterone levels and sperm concentration and decreased abnormal sperm morphology, however did not affect fertility. Further studies with older mice and different senolytics are necessary to elucidate the effects in the decline of sperm output (quality and quantity) associated with aging.


Sujet(s)
Quercétine , Testostérone , Femelle , Mâle , Animaux , Souris , Quercétine/pharmacologie , Dasatinib/pharmacologie , Sénothérapie , Mobilité des spermatozoïdes , Sperme/métabolisme , Spermatozoïdes
17.
Folia Microbiol (Praha) ; 68(6): 823-833, 2023 Dec.
Article de Anglais | MEDLINE | ID: mdl-37118368

RÉSUMÉ

In the constant search for new pharmacological compounds, molecular hybridisation is a well-known technique whereby two or more known pharmacophoric subunits are combined to create a new "hybrid" compound. This hybrid is expected to maintain the characteristics of the original compounds whilst demonstrating improvements to their pharmacological action. Accordingly, we report here a series of molecular hybrid compounds based upon eugenol and chloramphenicol pharmacophores. The hybrid compounds were screened for their in vitro antimicrobial potential against Gram-negative and Gram-positive bacteria and also rapidly growing mycobacteria (RGM). The results highlight that the antimicrobial profiles of the hybrid compounds improve in a very clear fashion when moving through the series. The most prominent results were found when comparing the activity of the hybrid compounds against some of the multidrug-resistant clinical isolates of Pseudomonas aeruginosa, methicillin-resistant clinical isolates of Staphylococcus aureus (MRSA) and clinical isolates of rapidly growing mycobacteria.


Sujet(s)
Anti-infectieux , Staphylococcus aureus résistant à la méticilline , Chloramphénicol/pharmacologie , Eugénol/pharmacologie , Pharmacophore , Anti-infectieux/pharmacologie , Staphylococcus aureus , Antibactériens/usage thérapeutique , Tests de sensibilité microbienne
18.
EBioMedicine ; 91: 104563, 2023 May.
Article de Anglais | MEDLINE | ID: mdl-37099842

RÉSUMÉ

BACKGROUND: The Omicron variant has challenged the control of the COVID-19 pandemic due to its immuno-evasive properties. The administration of a booster dose of a SARS-CoV-2 vaccine showed positive effects in the immunogenicity against SARS-CoV-2, effect that is even enhanced after the administration of a second booster. METHODS: During a phase-3 clinical trial, we evaluated the effect of a second booster of CoronaVac®, an inactivated vaccine administered 6 months after the first booster, in the neutralization of SARS-CoV-2 (n = 87). In parallel, cellular immunity (n = 45) was analyzed in stimulated peripheral mononuclear cells by flow cytometry and ELISPOT. FINDINGS: Although a 2.5-fold increase in neutralization of the ancestral SARS-CoV-2 was observed after the second booster when compared with prior its administration (Geometric mean units p < 0.0001; Geometric mean titer p = 0.0002), a poor neutralization against the Omicron variant was detected. Additionally, the activation of specific CD4+ T lymphocytes remained stable after the second booster and, importantly, equivalent activation of CD4+ T lymphocytes against the Omicron variant and the ancestral SARS-CoV-2 were found. INTERPRETATION: Although the neutralizing response against the Omicron variant after the second booster of CoronaVac® was slightly increased, these levels are far from those observed against the ancestral SARS-CoV-2 and could most likely fail to neutralize the virus. In contrast, a robust CD4+T cell response may confer protection against the Omicron variant. FUNDING: The Ministry of Health, Government of Chile, the Confederation of Production and Commerce, Chile and SINOVAC Biotech.NIHNIAID. The Millennium Institute on Immunology and Immunotherapy.


Sujet(s)
Vaccins contre la COVID-19 , COVID-19 , Adulte , Humains , COVID-19/prévention et contrôle , Pandémies , SARS-CoV-2 , Vaccins inactivés , Anticorps antiviraux , Anticorps neutralisants
19.
Life Sci ; 319: 121538, 2023 Apr 15.
Article de Anglais | MEDLINE | ID: mdl-36868399

RÉSUMÉ

AIMS: Reactive oxygen species like hydrogen peroxide (H2O2) are produced endogenously and may participate in intra- and extracellular signaling, including modulation of angiotensin II responses. In the present study, we investigated the effects of chronic subcutaneous (sc) administration of the catalase inhibitor 3-amino-1,2,4-triazole (ATZ) on arterial pressure, autonomic modulation of arterial pressure, hypothalamic expression of AT1 receptors and neuroinflammatory markers and fluid balance in 2-kidney, 1clip (2K1C) renovascular hypertensive rats. MATERIALS AND METHODS: Male Holtzman rats with a clip occluding partially the left renal artery and chronic sc injections of ATZ were used. KEY FINDINGS: Subcutaneous injections of ATZ (600 mg/kg of body weight/day) for 9 days in 2K1C rats reduced arterial pressure (137 ± 8, vs. saline: 182 ± 8 mmHg). ATZ also reduced the sympathetic modulation and enhanced the parasympathetic modulation of pulse interval, reducing the sympatho-vagal balance. Additionally, ATZ reduced mRNA expression for interleukins 6 and IL-1ß, tumor necrosis factor-α, AT1 receptor (0.77 ± 0.06, vs. saline: 1.47 ± 0.26 fold change), NOX 2 (0.85 ± 0.13, vs. saline: 1.75 ± 0.15 fold change) and the marker of microglial activation, CD 11 (0.47 ± 0.07, vs. saline, 1.34 ± 0.15 fold change) in the hypothalamus of 2K1C rats. Daily water and food intake and renal excretion were only slightly modified by ATZ. SIGNIFICANCE: The results suggest that the increase of endogenous H2O2 availability with chronic treatment with ATZ had an anti-hypertensive effect in 2K1C hypertensive rats. This effect depends on decreased activity of sympathetic pressor mechanisms and mRNA expression of AT1 receptors and neuroinflammatory markers possibly due to reduced angiotensin II action.


Sujet(s)
Hypertension rénovasculaire , Hypertension artérielle , Maladies du rein , Rats , Mâle , Animaux , Hypertension rénovasculaire/traitement médicamenteux , Angiotensine-II/pharmacologie , Catalase , Peroxyde d'hydrogène/pharmacologie , Hypertension artérielle/traitement médicamenteux , Rat Sprague-Dawley , ARN messager , Pression sanguine
20.
mSystems ; 8(2): e0081622, 2023 04 27.
Article de Anglais | MEDLINE | ID: mdl-36912639

RÉSUMÉ

The scale of post-transcriptional regulation and the implications of its interplay with other forms of regulation in environmental acclimation are underexplored for organisms of the domain Archaea. Here, we have investigated the scale of post-transcriptional regulation in the extremely halophilic archaeon Halobacterium salinarum NRC-1 by integrating the transcriptome-wide locations of transcript processing sites (TPSs) and SmAP1 binding, the genome-wide locations of antisense RNAs (asRNAs), and the consequences of RNase_2099C knockout on the differential expression of all genes. This integrated analysis has discovered that 54% of all protein-coding genes in the genome of this haloarchaeon are likely targeted by multiple mechanisms for putative post-transcriptional processing and regulation, with about 20% of genes likely being regulated by combinatorial schemes involving SmAP1, asRNAs, and RNase_2099C. Comparative analysis of mRNA levels (transcriptome sequencing [RNA-Seq]) and protein levels (sequential window acquisition of all theoretical fragment ion spectra mass spectrometry [SWATH-MS]) for 2,579 genes over four phases of batch culture growth in complex medium generated additional evidence for the conditional post-transcriptional regulation of 7% of all protein-coding genes. We demonstrate that post-transcriptional regulation may act to fine-tune specialized and rapid acclimation to stressful environments, e.g., as a switch to turn on gas vesicle biogenesis to promote vertical relocation under anoxic conditions and modulate the frequency of transposition by insertion sequence (IS) elements of the IS200/IS605, IS4, and ISH3 families. Findings from this study are provided as an atlas in a public Web resource (https://halodata.systemsbiology.net). IMPORTANCE While the transcriptional regulation landscape of archaea has been extensively investigated, we currently have limited knowledge about post-transcriptional regulation and its driving mechanisms in this domain of life. In this study, we collected and integrated omics data from multiple sources and technologies to infer post-transcriptionally regulated genes and the putative mechanisms modulating their expression at the protein level in Halobacterium salinarum NRC-1. The results suggest that post-transcriptional regulation may drive environmental acclimation by regulating hallmark biological processes. To foster discoveries by other research groups interested in the topic, we extended our integrated data to the public in the form of an interactive atlas (https://halodata.systemsbiology.net).


Sujet(s)
Archéobactéries , Transcriptome , Humains , Archéobactéries/génétique , Transcriptome/génétique , Génome , ARN antisens/génétique , Ribonucléases/génétique
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