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1.
Nature ; 625(7996): 728-734, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38200314

RESUMEN

Trees structure the Earth's most biodiverse ecosystem, tropical forests. The vast number of tree species presents a formidable challenge to understanding these forests, including their response to environmental change, as very little is known about most tropical tree species. A focus on the common species may circumvent this challenge. Here we investigate abundance patterns of common tree species using inventory data on 1,003,805 trees with trunk diameters of at least 10 cm across 1,568 locations1-6 in closed-canopy, structurally intact old-growth tropical forests in Africa, Amazonia and Southeast Asia. We estimate that 2.2%, 2.2% and 2.3% of species comprise 50% of the tropical trees in these regions, respectively. Extrapolating across all closed-canopy tropical forests, we estimate that just 1,053 species comprise half of Earth's 800 billion tropical trees with trunk diameters of at least 10 cm. Despite differing biogeographic, climatic and anthropogenic histories7, we find notably consistent patterns of common species and species abundance distributions across the continents. This suggests that fundamental mechanisms of tree community assembly may apply to all tropical forests. Resampling analyses show that the most common species are likely to belong to a manageable list of known species, enabling targeted efforts to understand their ecology. Although they do not detract from the importance of rare species, our results open new opportunities to understand the world's most diverse forests, including modelling their response to environmental change, by focusing on the common species that constitute the majority of their trees.


Asunto(s)
Bosques , Árboles , Clima Tropical , Biodiversidad , Árboles/anatomía & histología , Árboles/clasificación , Árboles/crecimiento & desarrollo , África , Asia Sudoriental
2.
J Virol ; 97(12): e0130923, 2023 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-38092658

RESUMEN

IMPORTANCE: Giant viruses are noteworthy not only due to their enormous particles but also because of their gigantic genomes. In this context, a fundamental question has persisted: how did these genomes evolve? Here we present the discovery of cedratvirus pambiensis, featuring the largest genome ever described for a cedratvirus. Our data suggest that the larger size of the genome can be attributed to an unprecedented number of duplicated genes. Further investigation of this phenomenon in other viruses has illuminated gene duplication as a key evolutionary mechanism driving genome expansion in diverse giant viruses. Although gene duplication has been described as a recurrent event in cellular organisms, our data highlights its potential as a pivotal event in the evolution of gigantic viral genomes.


Asunto(s)
Evolución Molecular , Duplicación de Gen , Virus Gigantes , Genoma Viral , Virus Gigantes/genética , Filogenia
3.
Am J Med Genet A ; : e63602, 2024 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-38517102

RESUMEN

Ramon syndrome (OMIM #266270) was first described in a patient with cherubism, gingival fibromatosis, epilepsy, intellectual disability, hypertrichosis, and stunted growth. In 2018, Mehawej et al. described a patient with Ramon syndrome in whom a homozygous variant in ELMO2 was identified, suggesting that this gene may be the causative for this syndrome. ELMO2 biallelic pathogenic variants were also described in patients with a primary intraosseous vascular malformation (PIVM; OMIM #606893). These patients presented gingival bleeding and cherubism phenotype. Herein, a patient with gingival hypertrophy, neurodevelopmental delay, and cherubism phenotype with a novel homozygous predicted loss-of-function (LOF) variant in the ELMO2 gene and family recurrence was reported. A surgical approach to treat gingival bleeding and mandible vascular malformation was also described. Furthermore, this study includes a comprehensive literature review of molecular data regarding the ELMO2 gene. All the variants, except one described in the ELMO2, were predicted as LOF, including our patient's variant. There is an overlapping between PIVM, also caused by LOF biallelic variants in the ELMO2 gene, and Ramon syndrome, which can suggest that they are not different entities. However, due to a limited number of cases described with molecular evaluation, it is hard to establish a genotype-phenotype correlation. Our study supports that LOF pathogenic biallelic variants in the ELMO2 gene cause a phenotype that has cherubism and gingival hypertrophy as main characteristics.

4.
Virol J ; 21(1): 135, 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38858684

RESUMEN

The discovery of mimivirus in 2003 prompted the search for novel giant viruses worldwide. Despite increasing interest, the diversity and distribution of giant viruses is barely known. Here, we present data from a 2012-2022 study aimed at prospecting for amoebal viruses in water, soil, mud, and sewage samples across Brazilian biomes, using Acanthamoeba castellanii for isolation. A total of 881 aliquots from 187 samples covering terrestrial and marine Brazilian biomes were processed. Electron microscopy and PCR were used to identify the obtained isolates. Sixty-seven amoebal viruses were isolated, including mimiviruses, marseilleviruses, pandoraviruses, cedratviruses, and yaraviruses. Viruses were isolated from all tested sample types and almost all biomes. In comparison to other similar studies, our work isolated a substantial number of Marseillevirus and cedratvirus representatives. Taken together, our results used a combination of isolation techniques with microscopy, PCR, and sequencing and put highlight on richness of giant virus present in different terrestrial and marine Brazilian biomes.


Asunto(s)
Virus Gigantes , Brasil , Virus Gigantes/aislamiento & purificación , Virus Gigantes/genética , Virus Gigantes/clasificación , Virus Gigantes/ultraestructura , Filogenia , Reacción en Cadena de la Polimerasa , Acanthamoeba castellanii/virología , Acanthamoeba castellanii/aislamiento & purificación , Microbiología del Suelo , Aguas del Alcantarillado/virología , Análisis de Secuencia de ADN , Agua de Mar/virología , Microbiología del Agua
5.
Clin Auton Res ; 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38878143

RESUMEN

PURPOSE: Central and peripheral chemoreceptors are hypersensitized in patients with heart failure with reduced ejection fraction. Whether this autonomic alteration occurs in patients with heart failure with preserved ejection fraction (HFpEF) remains little known. We test the hypothesis that the central and peripheral chemoreflex control of muscle sympathetic nerve activity (MSNA) is altered in HFpEF. METHODS: Patients aged 55-80 years with symptoms of heart failure, body mass index ≤ 35 kg/m2, left ventricular ejection fraction > 50%, left atrial volume index > 34 mL/m2, left ventricular early diastolic filling velocity and early diastolic tissue velocity of mitral annulus ratio (E/e' index) ≥ 13, and BNP levels > 35 pg/mL were included in the study (HFpEF, n = 9). Patients without heart failure with preserved ejection fraction (non-HFpEF, n = 9), aged-paired, were also included in the study. Peripheral chemoreceptors stimulation (10% O2 and 90% N2, with CO2 titrated) and central chemoreceptors stimulation (7% CO2 and 93% O2) were conducted for 3 min. MSNA was evaluated by microneurography technique, and forearm blood flow (FBF) by venous occlusion plethysmography. RESULTS: During hypoxia, MSNA responses were greater (p < 0.001) and FBF responses were lower in patients with HFpEF (p = 0.006). Likewise, MSNA responses during hypercapnia were higher (p < 0.001) and forearm vascular conductance (FVC) levels were lower (p = 0.030) in patients with HFpEF. CONCLUSIONS: Peripheral and central chemoreflex controls of MSNA are hypersensitized in patients with HFpEF, which seems to contribute to the increase in MSNA in these patients. In addition, peripheral and central chemoreceptors stimulation in patients with HFpEF causes muscle vasoconstriction.

6.
Proc Biol Sci ; 290(2006): 20231066, 2023 09 13.
Artículo en Inglés | MEDLINE | ID: mdl-37700646

RESUMEN

Tropical lands harbour the highest number of species, resulting in the ubiquitous latitudinal diversity gradient (LDG). However, exceptions to this pattern have been observed in some taxa, explained by the interaction between the evolutionary histories and environmental factors that constrain species' physiological and ecological requirements. Here, we applied a deconstruction approach to map the detailed species richness patterns of Actinopterygian freshwater fishes at the class and order levels and to disentangle their drivers using geographical ranges and a phylogeny, comprising 77% (12 557) of all described species. We jointly evaluated seven evolutionary and ecological hypotheses posited to explain the LDG: diversification rate, time for speciation, species-area relationship, environmental heterogeneity, energy, temperature seasonality and past temperature stability. We found distinct diversity gradients across orders, including expected, bimodal and inverse LDGs. Despite these differences, the positive effect of evolutionary time explained patterns for all orders, where species-rich regions are inhabited by older species compared to species-poor regions. Overall, the LDG of each order has been shaped by a unique combination of factors, highlighting the importance of performing a joint evaluation of evolutionary, historical and ecological factors at different taxonomic levels to reach a comprehensive understanding on the causes driving global species richness patterns.


Asunto(s)
Evolución Biológica , Peces , Animales , Filogenia , Agua Dulce , Geografía
7.
Clin Sci (Lond) ; 137(7): 543-559, 2023 04 13.
Artículo en Inglés | MEDLINE | ID: mdl-36972169

RESUMEN

Poor disease outcomes and lethality are directly related to endothelial dysfunction in betacoronavirus infections. Here, we investigated the mechanisms underlying the vascular dysfunction caused by the betacoronaviruses MHV-3 and SARS-CoV-2. Wild-type C57BL/6 (WT) and knockout mice for inducible nitric oxide synthase (iNOS-/-) or TNF receptor 1 (TNFR1-/-) were infected with MHV-3, and K18-hACE2 transgenic mice expressing human ACE2 were infected with SARS-CoV-2. Isometric tension was used to evaluate vascular function. Protein expression was determined by immunofluorescence. Tail-cuff plethysmography and Doppler were used to assess blood pressure and flow, respectively. Nitric oxide (NO) was quantified with the DAF probe. ELISA was used to assess cytokine production. Survival curves were estimated using Kaplan-Meier. MHV-3 infection reduced aortic and vena cava contractility, arterial blood pressure, and blood flow, resulting in death. Resistance mesenteric arteries showed increased contractility. The contractility of the aorta was normalized by removing the endothelium, inhibiting iNOS, genetically deleting iNOS, or scavenging NO. In the aorta, iNOS and phospho-NF-kB p65 subunit expression was enhanced, along with basal NO production. TNF production was increased in plasma and vascular tissue. Genetic deletion of TNFR1 prevented vascular changes triggered by MHV-3, and death. Basal NO production and iNOS expression were also increased by SARS-CoV-2. In conclusion, betacoronavirus induces an endothelium-dependent decrease in contractility in macro-arteries and veins, leading to circulatory failure and death via TNF/iNOS/NO. These data highlight the key role of the vascular endothelium and TNF in the pathogenesis and lethality of coronaviruses.


Asunto(s)
COVID-19 , Choque , Ratones , Humanos , Animales , Óxido Nítrico Sintasa de Tipo II/genética , Óxido Nítrico Sintasa de Tipo II/metabolismo , Óxido Nítrico Sintasa/metabolismo , Receptores Tipo I de Factores de Necrosis Tumoral/genética , Receptores Tipo I de Factores de Necrosis Tumoral/metabolismo , SARS-CoV-2/metabolismo , Ratones Endogámicos C57BL , Endotelio Vascular/metabolismo , Óxido Nítrico/metabolismo , Ratones Transgénicos , Arterias Mesentéricas/metabolismo
8.
Inflamm Res ; 72(10-11): 2073-2088, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37837557

RESUMEN

OBJECTIVE AND DESIGN: The present study aimed to investigate the neurochemical and behavioral effects of the acute consequences after coronavirus infection through a murine model. MATERIAL: Wild-type C57BL/6 mice were infected intranasally (i.n) with the murine coronavirus 3 (MHV-3). METHODS: Mice underwent behavioral tests. Euthanasia was performed on the fifth day after infection (5 dpi), and the brain tissue was subjected to plaque assays for viral titration, ELISA, histopathological, immunohistochemical and synaptosome analysis. RESULTS: Increased viral titers and mild histological changes, including signs of neuronal degeneration, were observed in the cerebral cortex of infected mice. Importantly, MHV-3 infection induced an increase in cortical levels of glutamate and calcium, which is indicative of excitotoxicity, as well as increased levels of pro-inflammatory cytokines (IL-6, IFN-γ) and reduced levels of neuroprotective mediators (BDNF and CX3CL1) in the mice brain. Finally, behavioral analysis showed impaired motor, anhedonia-like and anxiety-like behaviors in animals infected with MHV-3. CONCLUSIONS: In conclusion, the data presented emulate many aspects of the acute neurological outcomes seen in patients with COVID-19. Therefore, this model may provide a preclinical platform to study acute neurological sequelae induced by coronavirus infection and test possible therapies.


Asunto(s)
COVID-19 , Virus de la Hepatitis Murina , Humanos , Animales , Ratones , Ratones Endogámicos C57BL , Virus de la Hepatitis Murina/metabolismo , Citocinas/metabolismo , COVID-19/patología , Encéfalo/metabolismo
9.
Phys Chem Chem Phys ; 25(22): 15518-15530, 2023 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-37249495

RESUMEN

To control biochemical processes, non-covalent interactions involving cations are activated by protons or electrons. In the present study, the bonding situation between: (i) carboxylic acid or (ii) ferrocene-functionalized crown ether derivatives and cations (Li+, Na+ or K+) has been elucidated and, mainly, tuned by the substitution of hydrogen atoms by electron donor (-NH2) or acceptor (-NO2) groups. The deprotonation of the carboxyl groups improves the interaction with the cations through more favorable electrostatic O⋯cation interactions. Reducing the ferrocene structures favors cationic recognition supported by a less unfavorable iron⋯cation binding. The receptors preferably interact with smaller cations because of more attractive electrostatic and orbital (σ or π) O⋯cation interactions. The presence of electron donor or acceptor groups in the carboxylic acid-functionalized crown ethers promotes less attractive interactions with the cations, mainly due to the less favorable electrostatic O⋯Na+ interactions. The -H → -NH2 substitution in the ferrocene framework favors the cationic recognition. It is based on the strengthening of the electrostatic and σ O⋯Na+ and H2N⋯Na+ bonds. The (i) absence of repulsive electrostatic iron⋯cation interactions, or (ii) the presence of oxygen atoms with large electron density, ensures carboxylic acid-functionalized crown ethers have more favorable interactions with cations than ferrocene compounds. Therefore, this work has demonstrated how cation recognition can be improved by structural changes in carboxylic acid- or ferrocene-functionalized crown ethers and has shown that the carboxylic acid molecules appear to be better candidates for cation recognition than ferrocene derivatives.

10.
Biofouling ; 39(7): 719-729, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37698054

RESUMEN

The present study aimed to: (1) evaluate the influence of the steroid hormones (SH) on biofilm development; (2) investigate the formation of persister cells (PC) in biofilms; and (3) investigate the influence of SH on PC formation. Biofilms were derived from vulvovaginal candidiasis (VVC) samples and evaluated by three models: microcosm biofilms grown in Vaginal Fluid Simulator Medium (MiB-VFSM); monospecies biofilms grown in VFSM (MoB-VFSM) and RPMI media (MoB-RPMI). SH altered cell counting and biomass of biofilms grown in VSFM; MoB-RPMI were negatively affected by SH. SH stimulated the formation of PC in MiB-VFSM but not MoB-VFSM; MoB-RPMI showed a lower number of PC in the presence of SH. The results showed that SH altered the dynamics of biofilm formation and development, depending on the study model. The data suggest the influence of hormones on the physiology of Candida biofilms and reinforce the importance of PC in the pathogenesis of VVC.

11.
Proc Natl Acad Sci U S A ; 117(28): 16579-16586, 2020 07 14.
Artículo en Inglés | MEDLINE | ID: mdl-32601223

RESUMEN

Here we report the discovery of Yaravirus, a lineage of amoebal virus with a puzzling origin and evolution. Yaravirus presents 80-nm-sized particles and a 44,924-bp dsDNA genome encoding for 74 predicted proteins. Yaravirus genome annotation showed that none of its genes matched with sequences of known organisms at the nucleotide level; at the amino acid level, six predicted proteins had distant matches in the nr database. Complimentary prediction of three-dimensional structures indicated possible function of 17 proteins in total. Furthermore, we were not able to retrieve viral genomes closely related to Yaravirus in 8,535 publicly available metagenomes spanning diverse habitats around the globe. The Yaravirus genome also contained six types of tRNAs that did not match commonly used codons. Proteomics revealed that Yaravirus particles contain 26 viral proteins, one of which potentially representing a divergent major capsid protein (MCP) with a predicted double jelly-roll domain. Structure-guided phylogeny of MCP suggests that Yaravirus groups together with the MCPs of Pleurochrysis endemic viruses. Yaravirus expands our knowledge of the diversity of DNA viruses. The phylogenetic distance between Yaravirus and all other viruses highlights our still preliminary assessment of the genomic diversity of eukaryotic viruses, reinforcing the need for the isolation of new viruses of protists.


Asunto(s)
Acanthamoeba castellanii/virología , Virus ADN/aislamiento & purificación , Virus ADN/química , Virus ADN/clasificación , Virus ADN/genética , Genoma Viral , Filogenia , Proteínas Virales/genética
12.
Lasers Med Sci ; 38(1): 221, 2023 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-37749444

RESUMEN

Photobiomodulation (PBM) has been proposed as a strategy to improve the regenerative capacity of human adipose-derived stem cells (hASCs). Yet, this effect has been proved in 2D culture conditions. To analyze the effect of different doses of laser irradiation (660 nm) with different levels of energy (1 J, 2 J and 6 J) on hASCs cultured at 2D and 3D conditions. We used gellan gum spongy-like hydrogels as a biomaterial to 3D culture hASCs. Different doses (1-7 daily irradiations) and energy levels (1-6 J) of PBM were applied, and the metabolic activity, viability, proliferation, and release of ROS and IL-8 was evaluated up to 7 days. In 3D, cell proliferation increased at high energy (6 J) and after a single dose of irradiation, while in 2D, metabolic activity and proliferation was enhanced only after 3 doses and independently of the energy. More than 1 dose was needed to promote ROS secretion both in 2D and 3D culture conditions. Interestingly, a decrease of IL-8 secretion was detected only in 3D after 3-7 daily irradiations. Overall, hASCs response to PBM was not only dependent on the energy level and the number of applied stimuli, but also on the in vitro culture conditions.


Asunto(s)
Interleucina-8 , Células Madre Mesenquimatosas , Humanos , Especies Reactivas de Oxígeno , Adipocitos , Vendajes
13.
Clin Oral Investig ; 27(11): 6471-6482, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37718381

RESUMEN

OBJECTIVE: To analyze the clinical and microbiological efficacy of antimicrobial photodynamic therapy (aPDT) in patients with erythematous candidiasis (EC). METHODS: This study was a controlled and randomized clinical trial in patients diagnosed with EC, who were allocated into a control group (CG) and experimental group (EG) treated with nystatin oral suspension and aPDT with methylene blue 0.1%, respectively. A clinical index was used to classify the EC lesions from mild to severe and assess the treatment efficacy. Microbiological samples were collected before and after aPDT session and analyzed by counting colony-forming units (CFUs) of Candida and Staphylococcus sp. RESULTS: A total of 41 patients (CG (n = 18); EG (n = 23)) were analyzed in our research. Of these, 16 (94.1%) of the CG and 16 (84.2%) of the EG exhibited complete remission of the lesions. Regarding the degree of the lesion, it was observed that the severe lesions were more difficult to present remission, while all the mild and moderate lesions showed complete regression (p = 0.001). The microbiological analysis showed that Candida albicans and Staphylococcus sp. were the most prevalent microorganisms, and the aPDT group showed a decrease in CFUs of these microorganisms after the first aPDT session (p < 0.05). CONCLUSIONS: aPDT proved to be a clinically and microbiologically effective therapy for treating EC. TRIAL REGISTRATION: Registered at ClinicalTrials.gov; Set 12th, 2019; No. RBR-8w8599. CLINICAL RELEVANCE: aPDT is a promising alternative treatment since it presents satisfactory results and does not cause damage to oral tissues or develop resistance to the treatment.


Asunto(s)
Antiinfecciosos , Candidiasis Bucal , Fotoquimioterapia , Humanos , Antiinfecciosos/uso terapéutico , Candida albicans , Candidiasis Bucal/tratamiento farmacológico , Azul de Metileno , Fotoquimioterapia/métodos , Fármacos Fotosensibilizantes
14.
ScientificWorldJournal ; 2023: 4376545, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37404241

RESUMEN

Introduction: Universal single-shade composite resins are characterized by a property that enables the creation of restorations that mimic tooth structure to the extent possible with fewer shades of color. Objectives: This study aimed to instrumentally and visually evaluate the color correspondence of two single-shade composite resins in extracted human teeth multishade composite resins. Methods: Upper central incisors and upper and/or lower molars with intact buccal surfaces were selected. The study consisted of a control group (n = 20): Z250 XT (3M ESPE) (G1) multishade composite resin in colors A1 to A4, and a test group (n = 20) divided further into two equal groups, consisting of single-shade composite resin Omnichroma (Tokuyama Dental) (G2) and single-shade composite resin Vittra APS Unique from (FGM) (G3). Instrumental evaluation was performed using a spectrophotometer, and visual evaluation was performed by three observers. Descriptive measurements related to the differences in color obtained through instrumental means were analyzed using mean and standard deviation, wherein the means were compared using ANOVA, applying the Bonferroni post hoc test. Results: A statistically significant difference was observed among the groups (G1, G2, and G3) (ANOVA: p < 0.001). For the visual assessment, regardless of the assessment group, 77.49% of the teeth were within the acceptable color-match classification, with the single-shade resins showing better correspondence than the multishade resins. Conclusion: Single-shade composite resins showed different color-matching results when compared to multishade resins, both in spectrophotometry and visual evaluations. Clinical Significance. Single-shade composite resins simplify the shade-selection process and are promising materials for use in dental practice.


Asunto(s)
Resinas Acrílicas , Resinas Compuestas , Humanos , Resinas Compuestas/química , Diente Molar , Extracción Dental , Color , Ensayo de Materiales
15.
Medicina (Kaunas) ; 59(4)2023 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-37109768

RESUMEN

Background and objectives: Capsule endoscopy (CE) is a non-invasive method to inspect the small bowel that, like other enteroscopy methods, requires adequate small-bowel cleansing to obtain conclusive results. Artificial intelligence (AI) algorithms have been seen to offer important benefits in the field of medical imaging over recent years, particularly through the adaptation of convolutional neural networks (CNNs) to achieve more efficient image analysis. Here, we aimed to develop a deep learning model that uses a CNN to automatically classify the quality of intestinal preparation in CE. Methods: A CNN was designed based on 12,950 CE images obtained at two clinical centers in Porto (Portugal). The quality of the intestinal preparation was classified for each image as: excellent, ≥90% of the image surface with visible mucosa; satisfactory, 50-90% of the mucosa visible; and unsatisfactory, <50% of the mucosa visible. The total set of images was divided in an 80:20 ratio to establish training and validation datasets, respectively. The CNN prediction was compared with the classification established by consensus of a group of three experts in CE, currently considered the gold standard to evaluate cleanliness. Subsequently, how the CNN performed in diagnostic terms was evaluated using an independent validation dataset. Results: Among the images obtained, 3633 were designated as unsatisfactory preparation, 6005 satisfactory preparation, and 3312 with excellent preparation. When differentiating the classes of small-bowel preparation, the algorithm developed here achieved an overall accuracy of 92.1%, with a sensitivity of 88.4%, a specificity of 93.6%, a positive predictive value of 88.5%, and a negative predictive value of 93.4%. The area under the curve for the detection of excellent, satisfactory, and unsatisfactory classes was 0.98, 0.95, and 0.99, respectively. Conclusions: A CNN-based tool was developed to automatically classify small-bowel preparation for CE, and it was seen to accurately classify intestinal preparation for CE. The development of such a system could enhance the reproducibility of the scales used for such purposes.


Asunto(s)
Endoscopía Capsular , Aprendizaje Profundo , Humanos , Endoscopía Capsular/métodos , Inteligencia Artificial , Reproducibilidad de los Resultados , Redes Neurales de la Computación
16.
J Antimicrob Chemother ; 77(6): 1676-1684, 2022 05 29.
Artículo en Inglés | MEDLINE | ID: mdl-35368079

RESUMEN

BACKGROUND: During the COVID-19 pandemic, the burden of nosocomial infections caused by MDR pathogens has caused a shortage of polymyxins. Thus, we evaluated the in vitro synergism and antibiofilm activity of antimicrobial combinations and propose a test kit for synergism against carbapenem-resistant Acinetobacter baumannii (CRAB). METHODS: Fifty-six CRAB isolates were tested for synergy between meropenem, gentamicin and ampicillin/sulbactam. MICs were determined by broth microdilution. Synergism was tested using chequerboard analysis, followed by a time-kill curve. Additionally, minimum biofilm eradication concentration was determined and the antibiofilm activity of the combinations was evaluated by MTT assay and biomass reduction. A test kit was developed for routine laboratory testing to detect synergism. RESULTS: All CRAB isolates were resistant to gentamicin and ampicillin/sulbactam. Chequerboard synergism occurred against 75% of the isolates. Meropenem + ampicillin/sulbactam was the most frequent combination with synergism (69%), followed by ampicillin/sulbactam + gentamicin (64%) and meropenem + gentamicin (51%). All combinations presented only bacteriostatic activity and no bactericidal or antibiofilm effects. The routine laboratory test showed 100% accuracy compared with other in vitro assays. CONCLUSIONS: Our study demonstrates the potential role of antibiotic combinations against planktonic bacteria. In vitro synergism is possible and can be an alternative treatment for patients with CRAB infection during a polymyxin shortage.


Asunto(s)
Infecciones por Acinetobacter , Acinetobacter baumannii , COVID-19 , Infecciones por Acinetobacter/microbiología , Ampicilina , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Biopelículas , Farmacorresistencia Bacteriana Múltiple , Sinergismo Farmacológico , Gentamicinas/farmacología , Humanos , Meropenem/farmacología , Pruebas de Sensibilidad Microbiana , Pandemias , Polimixinas , Sulbactam/farmacología
17.
J Virol ; 95(22): e0127621, 2021 10 27.
Artículo en Inglés | MEDLINE | ID: mdl-34495692

RESUMEN

The emergence of life-threatening zoonotic diseases caused by betacoronaviruses, including the ongoing coronavirus disease 19 (COVID-19) pandemic, has highlighted the need for developing preclinical models mirroring respiratory and systemic pathophysiological manifestations seen in infected humans. Here, we showed that C57BL/6J wild-type mice intranasally inoculated with the murine betacoronavirus murine hepatitis coronavirus 3 (MHV-3) develop a robust inflammatory response leading to acute lung injuries, including alveolar edema, hemorrhage, and fibrin thrombi. Although such histopathological changes seemed to resolve as the infection advanced, they efficiently impaired respiratory function, as the infected mice displayed restricted lung distention and increased respiratory frequency and ventilation. Following respiratory manifestation, the MHV-3 infection became systemic, and a high virus burden could be detected in multiple organs along with morphological changes. The systemic manifestation of MHV-3 infection was also marked by a sharp drop in the number of circulating platelets and lymphocytes, besides the augmented concentration of the proinflammatory cytokines interleukin 1 beta (IL-1ß), IL-6, IL-12, gamma interferon (IFN-γ), and tumor necrosis factor (TNF), thereby mirroring some clinical features observed in moderate and severe cases of COVID-19. Importantly, both respiratory and systemic changes triggered by MHV-3 infection were greatly prevented by blocking TNF signaling, either via genetic or pharmacologic approaches. In line with this, TNF blockage also diminished the infection-mediated release of proinflammatory cytokines and virus replication of human epithelial lung cells infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Collectively, results show that MHV-3 respiratory infection leads to a large range of clinical manifestations in mice and may constitute an attractive, lower-cost, biosafety level 2 (BSL2) in vivo platform for evaluating the respiratory and multiorgan involvement of betacoronavirus infections. IMPORTANCE Mouse models have long been used as valuable in vivo platforms to investigate the pathogenesis of viral infections and effective countermeasures. The natural resistance of mice to the novel betacoronavirus SARS-CoV-2, the causative agent of COVID-19, has launched a race toward the characterization of SARS-CoV-2 infection in other animals (e.g., hamsters, cats, ferrets, bats, and monkeys), as well as adaptation of the mouse model, by modifying either the host or the virus. In the present study, we utilized a natural pathogen of mice, MHV, as a prototype to model betacoronavirus-induced acute lung injure and multiorgan involvement under biosafety level 2 conditions. We showed that C57BL/6J mice intranasally inoculated with MHV-3 develops severe disease, which includes acute lung damage and respiratory distress that precede systemic inflammation and death. Accordingly, the proposed animal model may provide a useful tool for studies regarding betacoronavirus respiratory infection and related diseases.


Asunto(s)
Infecciones por Coronavirus/patología , Modelos Animales de Enfermedad , Pulmón/patología , Virus de la Hepatitis Murina/patogenicidad , Animales , Línea Celular , Contención de Riesgos Biológicos , Infecciones por Coronavirus/inmunología , Infecciones por Coronavirus/virología , Citocinas/metabolismo , Humanos , Inflamación , Hígado/patología , Hígado/virología , Pulmón/virología , Ratones , Virus de la Hepatitis Murina/efectos de los fármacos , Virus de la Hepatitis Murina/fisiología , SARS-CoV-2/efectos de los fármacos , SARS-CoV-2/patogenicidad , SARS-CoV-2/fisiología , Transducción de Señal/efectos de los fármacos , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Factor de Necrosis Tumoral alfa/metabolismo , Replicación Viral/efectos de los fármacos
18.
New Phytol ; 236(5): 1856-1870, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36056465

RESUMEN

The Xanthomonas transcription activator-like effector (TALE) protein AvrBs3 transcriptionally activates the executor-type resistance (R) gene Bs3 from pepper (Capsicum annuum), thereby triggering a hypersensitive cell death reaction (HR). AvrBs3 also triggers an HR in tomato (Solanum lycopersicum) upon recognition by the nucleotide-binding leucine-rich repeat (NLR) R protein Bs4. Whether the executor-type R protein Bs3 and the NLR-type R protein Bs4 use common or distinct signalling components to trigger an HR remains unclear. CRISPR/Cas9-mutagenesis revealed, that the immune signalling node EDS1 is required for Bs4- but not for Bs3-dependent HR, suggesting that NLR- and executor-type R proteins trigger an HR via distinct signalling pathways. CRISPR/Cas9-mutagenesis also revealed that tomato Bs4 suppresses the virulence function of both TALEs, the HR-inducing AvrBs3 protein and of AvrHah1, a TALE that does not trigger an HR in tomato. Analysis of AvrBs3- and AvrHah1-induced host transcripts and disease phenotypes in CRISPR/Cas9-induced bs4 mutant plants indicates that both TALEs target orthologous transcription factor genes to promote disease in tomato and pepper host plants. Our studies display that tomato mutants lacking the TALE-sensing Bs4 protein provide a novel platform to either uncover TALE-induced disease phenotypes or genetically dissect components of executor-triggered HR.


Asunto(s)
Solanum lycopersicum , Xanthomonas , Efectores Tipo Activadores de la Transcripción/genética , Solanum lycopersicum/genética , Solanum lycopersicum/metabolismo , Enfermedades de las Plantas/genética , Proteínas Bacterianas/metabolismo , Xanthomonas/genética , Hojas de la Planta/metabolismo , Fenotipo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
19.
Value Health ; 25(6): 1042-1056, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35667776

RESUMEN

OBJECTIVES: We aimed to determine the effectiveness of pneumococcal vaccines on otitis media (OM) and acute otitis media (AOM) in children. METHODS: We conducted a systematic search in databases PubMed (MEDLINE), Embase, Lilacs, and Web of Science. We included observational studies that evaluated any pneumococcal vaccine - including 7, 10, and 13-valent pneumococcal conjugate vaccines (PCV7, PCV10, and PCV13) and 23-valent polysaccharide vaccines (PPSV23) as the intervention, in children aged less than five years. RESULTS: Out of the 2112 screened studies, 48 observational studies complied with the eligibility criteria and therefore were included in this review. Of the included studies, 30 (63%) were before-after, eleven (23%) cohort, six (13%) time series, and one (2%) case-control study designs. Vaccine effectiveness (VE) in preventing OM or AOM varied by vaccine type. In children under 24 months VE ranged from 8% and 42.7% (PCV7), 5.6% to 84% (PCV10) and 2.2% to 68% (PCV13). In children aged less than 60 months, VE ranged between 13.2% and 39% for PCV7, 11% to 39% for PCV10 (only children under 48 months), and 39% to 41% (PCV13). CONCLUSIONS: Our results demonstrate significant effect of pneumococcal vaccination in decreasing OM or AOM in children under five years old in several countries supporting the public health value of introducing PCVs in national immunization programs.


Asunto(s)
Otitis Media , Infecciones Neumocócicas , Estudios de Casos y Controles , Niño , Preescolar , Humanos , Programas de Inmunización , Lactante , Otitis Media/prevención & control , Infecciones Neumocócicas/prevención & control , Vacunas Neumococicas/uso terapéutico , Vacunas Conjugadas
20.
Eur J Clin Pharmacol ; 78(6): 919-930, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35258665

RESUMEN

PURPOSE: The aim of this study is to investigate the association between hydrochlorothiazide (HCTZ) use and the risk of cutaneous and lip squamous cell carcinoma development. METHODOLOGY: We performed a systematic review and meta-analysis of case-control studies. We searched the Cochrane Library, PubMed, Scopus, Web of Science and LILACS. This study was registered in PROSPERO under protocol CRD42019129710. The meta-analysis was performed using the software Stata (version 12.0). RESULTS: A total of 2181 published studies referring to the theme were identified, from which six were included in this systematic review. Men were more frequently affected by cutaneous and lip squamous cell carcinoma than women, with a 1.42:1 ratio. The mean age for cutaneous and lip squamous cell carcinoma development was 73.7 years. This meta-analysis demonstrated a chance of developing cutaneous and lip squamous cell carcinoma in any region of the body in hydrochlorothiazide users of 1.76-fold higher than in non-users. In addition, a risk factor of 1.80 higher (CI 95% = 1.71-1.89) of cutaneous squamous cell carcinoma in the head and neck region was observed in HCTZ users. Moreover, in the analysis of the dose used, the chance of developing squamous cell carcinoma was 3.37-fold lower when the concentration of HCTZ used was less than 50,000 mg. CONCLUSIONS: Our results confirm the association between the use of hydrochlorothiazide and the cutaneous and lip squamous cell carcinoma development.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias de los Labios , Neoplasias Cutáneas , Anciano , Carcinoma de Células Escamosas/inducido químicamente , Carcinoma de Células Escamosas/complicaciones , Carcinoma de Células Escamosas/epidemiología , Femenino , Humanos , Hidroclorotiazida/efectos adversos , Labio/patología , Neoplasias de los Labios/inducido químicamente , Neoplasias de los Labios/complicaciones , Neoplasias de los Labios/epidemiología , Masculino , Neoplasias Cutáneas/inducido químicamente , Neoplasias Cutáneas/epidemiología
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