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1.
Liver Int ; 44(1): 180-190, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37872644

RESUMO

BACKGROUND: Porto-sinusoidal vascular disorder (PSVD) involves a group of rare vascular liver diseases of unknown aetiology that may lead to the development of portal hypertension and its life-threatening complications. Its pathophysiology is not well understood, and animal models described to date do not fully recapitulate human disease. METHODS: We developed three different PSVD rat models by either immunosensitization (repetitive intraportal LPS or intramuscular spleen extract injections) or toxic (Selfox: combination of FOLFOX and a selenium-enriched diet) treatment and characterized them at haemodynamic, histological, biochemical and transcriptional levels. We compared these results to human data. RESULTS: All three models developed significant portal hypertension, while only the LPS and the Selfox models displayed PSVD-specific and nonspecific histological alterations in the absence of cirrhosis. Transcriptional comparison between rat models and human data showed that both LPS and Selfox models recapitulate the main transcriptional alterations observed in humans, especially regarding haemostasis, oxidative phosphorylation and cell cycle regulation. Reproducibility and feasibility was higher for the Selfox model. CONCLUSIONS: The Selfox rat model faithfully reproduces the main alterations described in PSVD. Its use as a preclinical model for drug testing in progressing PSVD can be a significant step forward towards the development of new therapeutic targets for this rare condition.


Assuntos
Hipertensão Portal , Doenças Vasculares , Ratos , Humanos , Animais , Lipopolissacarídeos , Reprodutibilidade dos Testes , Cirrose Hepática/complicações , Perfilação da Expressão Gênica , Fígado
2.
Phys Chem Chem Phys ; 26(5): 4541-4554, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38241021

RESUMO

The bottom-up prediction of thermodynamic and mechanical behaviors of polymeric materials based on molecular dynamics (MD) simulation is of critical importance in polymer physics. Although the atomistically informed coarse-grained (CG) model can access greater spatiotemporal scales and retain essential chemical specificity, the temperature-transferable CG model is still a big challenge and hinders widespread application of this technique. Herein, we use a silicone polymer, i.e., polydimethylsiloxane (PDMS), having an incredibly low chain rigidity as a model system, combined with an energy-renormalization (ER) approach, to systematically develop a temperature-transferable CG model. Specifically, by introducing temperature-dependent ER factors to renormalize the effective distance and cohesive energy parameters, the developed CG model faithfully preserved the dynamics, mechanical and conformational behaviors compared with the target all-atomistic (AA) model from glassy to melt regimes, which was further validated by experimental data. With the developed CG model featuring tremendously improved computational efficiency, we systematically explored the influences of cohesive interaction strength and temperature on the dynamical heterogeneity and mechanical response of polymers, where we observed consistent trends with other linear polymers with varying chain rigidity and monomeric structures. This study serves as an extension of our proposed ER approach of developing temperature transferable CG models with diverse segmental structures, highlighting the critical role of cohesive interaction strength on CG modeling of polymer dynamics and thermomechanical behaviors.

3.
J Chem Phys ; 159(18)2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-37955325

RESUMO

Many modern anti-icing and anti-fouling coatings rely on soft, low surface energy elastomeric materials such as polydimethylsiloxane for their functionality. While the low surface energy is desirable for reducing adhesion, very little work considers the larger contribution to adhesive failure caused by the viscoelastic nature of elastomers. Here we examine several different siloxane elastomers using a JKR adhesion test, which was operated over a range of different speeds and temperatures. Additionally, we characterize the dynamic mechanical modulus over a large range of frequencies for each material. We note that surface energies of the materials are all similar, but variation in adhesion strength is clear in the data. The variation at low speeds is related to elastomer architecture but the speed dependence itself is independent of architecture. Qualitative correlations are noted between the JKR adhesion measurements and the dynamic moduli. Finally, an attempt is made to directly compare moduli and adhesion through the recent Persson-Brener model. Approximations of the model are shown to be inaccurate. The full model is found to be accurate at low speeds, although it fails to precisely capture higher speed behaviour.

4.
Int J Mol Sci ; 24(8)2023 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-37108839

RESUMO

This paper assesses the association of the insertion/deletion ACE (angiotensin-converting enzyme) variant (rs1799752 I/D) and the serum ACE activity with the severity of COVID-19 as well as its impact on post-COVID-19, and we compare these associations with those for patients with non-COVID-19 respiratory disorders. We studied 1252 patients with COVID-19, 104 subjects recovered from COVID-19, and 74 patients hospitalized with a respiratory disease different from COVID-19. The rs1799752 ACE variant was assessed using TaqMan® Assays. The serum ACE activity was determined using a colorimetric assay. The DD genotype was related to risk for invasive mechanical ventilation (IMV) requirement as an indicator of COVID-19 severity when compared to the frequencies of II + ID genotypes (p = 0.025, OR = 1.428, 95% CI = 1.046-1.949). In addition, this genotype was significantly higher in COVID-19 and post-COVID-19 groups than in the non-COVID-19 subjects. The serum ACE activity levels were lower in the COVID-19 group (22.30 U/L (13.84-32.23 U/L)), which was followed by the non-COVID-19 (27.94 U/L (20.32-53.36 U/L)) and post-COVID-19 subjects (50.00 U/L (42.16-62.25 U/L)). The DD genotype of the rs1799752 ACE variant was associated with the IMV requirement in patients with COVID-19, and low serum ACE activity levels could be related to patients with severe disease.


Assuntos
COVID-19 , Polimorfismo Genético , Humanos , COVID-19/genética , Genótipo , Peptidil Dipeptidase A/genética , Carboxipeptidases/metabolismo
5.
FASEB J ; 35(3): e21396, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33583073

RESUMO

We have recently reported that a specific pool of ceramide, located in the plasma membrane, mediated the effects of sublethal doses of the chemotherapeutic compound doxorubicin on enhancing cancer cell migration. We identified neutral sphingomyelinase 2 (nSMase2) as the enzyme responsible to generate this bioactive pool of ceramide. In this work, we explored the role of members of the protein phosphatases 1 family (PP1), and we identified protein phosphatase 1 alpha isoform (PP1 alpha) as the specific PP1 isoform to mediate this phenotype. Using a bioinformatics approach, we build a functional interaction network based on phosphoproteomics data on plasma membrane ceramide. This led to the identification of several ceramide-PP1 alpha downstream substrates. Studies on phospho mutants of ezrin (T567) and Scrib (S1378/S1508) demonstrated that their dephosphorylation is sufficient to enhance cell migration. In summary, we identified a mechanism where reduced doses of doxorubicin result in the dysregulation of cytoskeletal proteins and enhanced cell migration. This mechanism could explain the reported effects of doxorubicin worsening cancer metastasis in animal models.


Assuntos
Ceramidas/fisiologia , Doxorrubicina/farmacologia , Proteína Fosfatase 1/fisiologia , Adesão Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Células HeLa , Humanos
6.
EMBO J ; 36(17): 2567-2580, 2017 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-28701483

RESUMO

The role of second messengers in the diversion of cellular processes by pathogens remains poorly studied despite their importance. Among these, Ca2+ virtually regulates all known cell processes, including cytoskeletal reorganization, inflammation, or cell death pathways. Under physiological conditions, cytosolic Ca2+ increases are transient and oscillatory, defining the so-called Ca2+ code that links cell responses to specific Ca2+ oscillatory patterns. During cell invasion, Shigella induces atypical local and global Ca2+ signals. Here, we show that by hydrolyzing phosphatidylinositol-(4,5)bisphosphate, the Shigella type III effector IpgD dampens inositol-(1,4,5)trisphosphate (InsP3) levels. By modifying InsP3 dynamics and diffusion, IpgD favors the elicitation of long-lasting local Ca2+ signals at Shigella invasion sites and converts Shigella-induced global oscillatory responses into erratic responses with atypical dynamics and amplitude. Furthermore, IpgD eventually inhibits InsP3-dependent responses during prolonged infection kinetics. IpgD thus acts as a pathogen regulator of the Ca2+ code implicated in a versatility of cell functions. Consistent with this function, IpgD prevents the Ca2+-dependent activation of calpain, thereby preserving the integrity of cell adhesion structures during the early stages of infection.


Assuntos
Proteínas de Bactérias/metabolismo , Cálcio/metabolismo , Disenteria Bacilar/metabolismo , Interações Hospedeiro-Patógeno , Monoéster Fosfórico Hidrolases/metabolismo , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Shigella flexneri/fisiologia , Calpaína/metabolismo , Adesão Celular , Células HeLa , Humanos , Transdução de Sinais
7.
FASEB J ; 34(6): 7610-7630, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32307766

RESUMO

Chemotherapy has been reported to upregulate sphingomylinases and increase cellular ceramide, often linked to the induction to cell death. In this work, we show that sublethal doses of doxorubicin and vorinostat still increased cellular ceramide, which was located predominantly at the plasma membrane. To interrogate possible functions of this specific pool of ceramide, we used recombinant enzymes to mimic physiological levels of ceramide at the plasma membrane upon chemotherapy treatment. Using mass spectrometry and network analysis, followed by experimental confirmation, the results revealed that this pool of ceramide acutely regulates cell adhesion and cell migration pathways with weak connections to commonly established ceramide functions (eg, cell death). Neutral sphingomyelinase 2 (nSMase2) was identified as responsible for the generation of plasma membrane ceramide upon chemotherapy treatment, and both ceramide at the plasma membrane and nSMase2 were necessary and sufficient to mediate these "side" effects of chemotherapy on cell adhesion and migration. This is the first time a specific pool of ceramide is interrogated for acute signaling functions, and the results define plasma membrane ceramide as an acute signaling effector necessary and sufficient for regulation of cell adhesion and cell migration under chemotherapeutical stress.


Assuntos
Antineoplásicos/farmacologia , Adesão Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Ceramidas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Linhagem Celular Tumoral , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Células HeLa , Humanos , Fosforilação/efeitos dos fármacos , Esfingomielina Fosfodiesterase/metabolismo
8.
J Transl Med ; 18(1): 44, 2020 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-32000799

RESUMO

BACKGROUND: Crohn's disease (CD) is a multifactorial disease characterized by chronic intestinal inflammation. The increased visceral adiposity near the affected intestinal area, of which mesenteric adipose tissue (MAT) is the main component, is a feature of CD. Both protective and pathological roles have been attributed to this disease-associated tissue in CD. To understand the contribution of MAT to CD pathophysiology, a molecular and cellular signature of disease-associated MAT in CD patients was provided. METHODS: We performed an observational study with whole transcriptional analysis by RNA sequencing (RNA-seq) of MAT and ileal mucosa from CD patients with active disease and controls. qPCR and immunohistology were performed for validation analysis. RESULTS: RNA-seq identified 17 significantly regulated genes (|FC| > 1.5; FDR < 0.05) in CD-MAT compared to non-IBD controls, with a marked upregulation of plasma cell genes (i.e., IGLL5, MZB1, CD79A, POU2AF1, FCRL5, JCHAIN, DERL3, SDC1, PIM2). A less strict statistical cutoff value (|FC| > 1.5, nominal p ≤ 0.05) yielded a larger list of 651 genes in CD-MAT compared to controls. CD ileum showed the significant regulation compared to control ileum of 849 genes (|FC| > 1.5; FDR < 0.05) or 2654 genes (|FC| > 1.5, nominal p ≤ 0.05). Ingenuity Pathway Analysis revealed the significant regulation of pathways related to T- and B cell functionality in the MAT of CD patients. Despite the differences between the MAT and ileal signatures of CD patients, we identified a subset of 204 genes significantly modulated in both tissues compared to controls. This common signature included genes related to the plasma cell signature. Genes such as S100A8, S100A9 (calprotectin) and IL1B, which are associated with acute inflammatory response, were exclusively regulated in the ileal mucosa of CD disease. In contrast, some genes encoding for lymphocyte receptors such as MS4A1, CD3D and CD79A were exclusively regulated in CD-MAT, exhibiting a different pattern of immune cell activation compared to the ileal mucosa in CD patients. qPCR and immunohistology confirmed the presence of large infiltrates of CD3+ CD20+ lymphocytes and CD138+ plasma cells in CD-MAT. CONCLUSION: Our data strongly supports the role of CD-associated MAT as a site for T-, B- and plasma cell activation, and suggests that it could also act as a reservoir of memory immune responses.


Assuntos
Doença de Crohn , Tecido Adiposo , Linfócitos B , Doença de Crohn/genética , Humanos , Íleo , Mucosa Intestinal , Mesentério , Plasmócitos , Transdução de Sinais/genética , Linfócitos T
9.
Allergy ; 75(12): 3248-3260, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32277847

RESUMO

BACKGROUND: Allergic diseases often occur in combination (multimorbidity). Human blood transcriptome studies have not addressed multimorbidity. Large-scale gene expression data were combined to retrieve biomarkers and signaling pathways to disentangle allergic multimorbidity phenotypes. METHODS: Integrated transcriptomic analysis was conducted in 1233 participants with a discovery phase using gene expression data (Human Transcriptome Array 2.0) from whole blood of 786 children from three European birth cohorts (MeDALL), and a replication phase using RNA Sequencing data from an independent cohort (EVA-PR, n = 447). Allergic diseases (asthma, atopic dermatitis, rhinitis) were considered as single disease or multimorbidity (at least two diseases), and compared with no disease. RESULTS: Fifty genes were differentially expressed in allergic diseases. Thirty-two were not previously described in allergy. Eight genes were consistently overexpressed in all types of multimorbidity for asthma, dermatitis, and rhinitis (CLC, EMR4P, IL5RA, FRRS1, HRH4, SLC29A1, SIGLEC8, IL1RL1). All genes were replicated the in EVA-PR cohort. RT-qPCR validated the overexpression of selected genes. In MeDALL, 27 genes were differentially expressed in rhinitis alone, but none was significant for asthma or dermatitis alone. The multimorbidity signature was enriched in eosinophil-associated immune response and signal transduction. Protein-protein interaction network analysis identified IL5/JAK/STAT and IL33/ST2/IRAK/TRAF as key signaling pathways in multimorbid diseases. Synergistic effect of multimorbidity on gene expression levels was found. CONCLUSION: A signature of eight genes identifies multimorbidity for asthma, rhinitis, and dermatitis. Our results have clinical and mechanistic implications, and suggest that multimorbidity should be considered differently than allergic diseases occurring alone.


Assuntos
Asma , Hipersensibilidade , Rinite Alérgica , Rinite , Adolescente , Asma/epidemiologia , Asma/genética , Criança , Humanos , Hipersensibilidade/epidemiologia , Hipersensibilidade/genética , Multimorbidade , Rinite/epidemiologia , Rinite/genética , Rinite Alérgica/epidemiologia , Rinite Alérgica/genética , Transcriptoma
10.
Am J Physiol Lung Cell Mol Physiol ; 317(2): L222-L234, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31166128

RESUMO

We have analyzed the effect of the soluble guanylate cyclase (sGC) stimulator BAY 41-2272 in a therapeutic intervention in guinea pigs chronically exposed to cigarette smoke (CS). The effects of sGC stimulation on respiratory function, pulmonary hemodynamics, airspace size, vessel remodeling, and inflammatory cell recruitment to the lungs were evaluated in animals that had been exposed to CS for 3 mo. CS exposure was continued for an additional 3 mo in half of the animals and withdrawn in the other half. Animals that stopped CS exposure had slightly lower pulmonary artery pressure (PAP) and right ventricle (RV) hypertrophy than those who continued CS exposure, but they did not recover from the emphysema and the inflammatory cell infiltrate. Conversely, oral BAY 41-2272 administration stopped progression or even reversed the CS-induced emphysema in both current and former smokers, respectively. Furthermore, BAY 41-2272 produced a reduction in the RV hypertrophy, which correlated with a decrease in the PAP values. By contrast, the degree of vessel remodeling induced by CS remained unchanged in the treated animals. Functional network analysis suggested perforin/granzyme pathway downregulation as an action mechanism capable of stopping the progression of emphysema after sGC stimulation. The pathway analysis also showed normalization of the expression of cGMP-dependent serine/kinases. In conclusion, in guinea pigs chronically exposed to CS, sGC stimulation exerts beneficial effects on the lung parenchyma and the pulmonary vasculature, suggesting that sGC stimulators might be a potential alternative for chronic obstructive pulmonary disease treatment that deserves further evaluation.


Assuntos
Hemodinâmica/efeitos dos fármacos , Hipertensão Pulmonar/tratamento farmacológico , Enfisema Pulmonar/tratamento farmacológico , Fumaça , Guanilil Ciclase Solúvel/uso terapêutico , Animais , Guanilato Ciclase/metabolismo , Cobaias , Hipertensão Pulmonar/metabolismo , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Doença Pulmonar Obstrutiva Crônica/induzido quimicamente , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Doença Pulmonar Obstrutiva Crônica/metabolismo , Enfisema Pulmonar/metabolismo , Guanilil Ciclase Solúvel/metabolismo , Nicotiana , Vasodilatadores/farmacologia
11.
Ecotoxicology ; 27(6): 719-728, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29923076

RESUMO

The mirid Engytatus varians (Distant) is a promising biological control agent of the tomato borer, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), one of the most destructive pests of tomato (Solanum lycopersicum L.). The effects of five insecticides commonly used on tomato crops in Brazil were evaluated on E. varians in laboratory and semifield conditions. Glass Petri dish with residues of chlorfenapyr, thiamethoxam, and abamectin caused ˃90% mortality in both stages of the predator 72 h post-treatment, except imidacloprid that caused 78% of nymphs mortality. Teflubenzuron caused 24 and 66% mortality on adults and nymphs, respectively. The offspring of females derived from treated nymphs with teflubenzuron was significantly lower than the control but not when females were treated as adults. Longevity of males derived from nymphs treated with teflubenzuron was significantly reduced, but no effects were observed on females. When males and females were treated as adults with teflubenzuron there were no effects on their longevity. In the greenhouse-aged tomato plants, the 2 h-old residues of thiamethoxam, chlorfenapyr, and abamectin caused more than 70% of mortality of third instar of E. varians at 72 h post-treatment, 12 day-old residues of all three compounds caused a mortality lower than 30%. These data suggest that teflubenzuron can be associated with releases of E. varians adults, while the use of other evaluated pesticides should be avoided in this situation. Although, the low persistence of these products indicate that their spraying and later releases of E. varians adults on tomato crops are a possible strategy to control T. absoluta.


Assuntos
Heterópteros/efeitos dos fármacos , Inseticidas/toxicidade , Comportamento Predatório/efeitos dos fármacos , Animais , Brasil , Feminino , Heterópteros/crescimento & desenvolvimento , Larva/crescimento & desenvolvimento , Masculino , Mariposas/crescimento & desenvolvimento , Ninfa/efeitos dos fármacos , Ninfa/crescimento & desenvolvimento , Controle Biológico de Vetores
12.
Mol Phylogenet Evol ; 109: 113-137, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28069533

RESUMO

Myrteae (c. 2500 species; 51 genera) is the largest tribe of Myrtaceae and an ecologically important groups of angiosperms in the Neotropics. Systematic relationships in Myrteae are complex, hindering conservation initiatives and jeopardizing evolutionary modelling. A well-supported and robust phylogenetic hypothesis was here targeted towards a comprehensive understanding of the relationships within the tribe. The resultant topology was used as a base for key evolutionary analyses such as age estimation, historical biogeography and diversification rate patterns. One nuclear (ITS) and seven chloroplast (psbA-trnH, matK, ndhF, trnl-trnF, trnQ-rps16, rpl16 and rpl32-trnL) DNA regions for 115 taxa representing 46 out of the 51 genera in the tribe were accessed and analysed using maximum likelihood and Bayesian inference tools for phylogenetic reconstruction. Dates of diversification events were estimated and contrasted using two distinct fossil sets (macro and pollen) in BEAST. The subsequent dated phylogenies were compared and analysed for biogeographical patterns using BioGeoBEARS and diversification rates using BAMM. Myrteae phylogeny presents strong statistical support for three major clades within the tribe: Australasian group, Myrtus group and Main Neotropical Lineage. Dating results from calibration using macrofossil are an average of 20 million years older and show an early Paleocene origin of Myrteae, against a mid-Eocene one from the pollen fossil calibration. Biogeographic analysis shows the origin of Myrteae in Zealandia in both calibration approaches, followed by a widespread distribution throughout the still-linked Gondwana continents and diversification of Neotropical endemic lineages by later vicariance. Best configuration shift indicates three points of acceleration in diversification rates, all of them occurring in the Main Neotropical Lineage. Based on the reconstructed topology, several new taxonomic placements were recovered, including: the relative position of Myrtus communis, the placement of the Blepharocalyx group, the absence of generic endemism in the Caribbean, and the paraphyletism of the former Pimenta group. Distinct calibration approaches affect biogeography interpretation, increasing the number of necessary long distance dispersal events in the topology with older nodes. It is hypothesised that biological intrinsic factors such as modifications of embryo type and polyploidy might have played a role in accelerating shifts of diversification rates in Neotropical lineages. Future perspectives include formal subtribal classification, standardization of fossil calibration approaches and better links between diversification shifts and trait evolution.


Assuntos
Myrtaceae/genética , Teorema de Bayes , Calibragem , Cloroplastos/genética , Evolução Molecular , Fósseis , Genes de Plantas , Especiação Genética , Variação Genética , Tipagem de Sequências Multilocus , Myrtaceae/classificação , Filogenia , Filogeografia
13.
FASEB J ; 30(3): 1300-5, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26631482

RESUMO

Proliferative retinopathic diseases often progress in 2 phases: initial regression of retinal vasculature (phase 1) followed by subsequent neovascularization (NV) (phase 2). The immune system has been shown to aid in vascular pruning in such retinopathies; however, little is known about the role of the alternative complement pathway in the initial vascular regression phase. Using a mouse model of oxygen-induced retinopathy (OIR), we observed that alternative complement pathway-deficient mice (Fb(-/-)) exhibited a mild decrease in vascular loss at postnatal day (P)8 compared with age- and strain-matched controls (P = 0.035). Laser capture microdissection was used to isolate the retinal blood vessels. Expression of the complement inhibitors Cd55 and Cd59 was significantly decreased in blood vessels isolated from hyperoxic retinas compared with those from normoxic control mice. Vegf expression was measured at P8 and found to be significantly lower in OIR mice than in normoxic control mice (P = 0.0048). Further examination of specific Vegf isoform expression revealed a significant decrease in Vegf120 (P = 0.00032) and Vegf188 (P = 0.0092). In conjunction with the major modulating effects of Vegf during early retinal vascular development, our data suggest a modest involvement of the alternative complement pathway in targeting vessels for regression in the initial vaso-obliteration stage of OIR.


Assuntos
Via Alternativa do Complemento/imunologia , Neovascularização Patológica/imunologia , Retina/imunologia , Neovascularização Retiniana/imunologia , Vitreorretinopatia Proliferativa/imunologia , Animais , Animais Recém-Nascidos/imunologia , Animais Recém-Nascidos/metabolismo , Modelos Animais de Doenças , Hiperóxia/imunologia , Hiperóxia/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Neovascularização Patológica/patologia , Oxigênio/metabolismo , Isoformas de Proteínas/metabolismo , Retina/metabolismo , Neovascularização Retiniana/metabolismo , Vasos Retinianos/imunologia , Vasos Retinianos/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Vitreorretinopatia Proliferativa/metabolismo
14.
Vet Anaesth Analg ; 44(2): 228-236, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28190788

RESUMO

OBJECTIVE: To determine the effects of two dexmedetomidine continuous rate infusions on the minimum infusion rate of alfaxalone for total intravenous anaesthesia (TIVA), and subsequent haemodynamic and recovery effects in Greyhounds undergoing laparoscopic ovariohysterectomy. STUDY DESIGN: Prospective, randomized and blinded clinical study. ANIMALS: Twenty-four female Greyhounds. METHODS: Dogs were premedicated with dexmedetomidine 3 µg kg-1 and methadone 0.3 mg kg-1 intramuscularly. Anaesthesia was induced with IV alfaxalone to effect and maintained with a TIVA mixture of alfaxalone in combination with two different doses of dexmedetomidine (0.5 µg kg-1 hour-1 or 1 µg kg-1 hour-1; groups DEX0.5 and DEX1, respectively). The alfaxalone starting dose rate was 0.07 mg kg-1 minute-1 and was adjusted (± 0.02 mg kg-1 minute-1) every 5 minutes to maintain a suitable depth of anaesthesia. A rescue alfaxalone bolus (0.5 mg kg-1 IV) was administered if dogs moved or swallowed. The number of rescue boluses was recorded. Heart rate, arterial blood pressure and arterial blood gas were monitored. Qualities of sedation, induction and recovery were scored. Differences between groups were tested for statistical significance using a Student's t test or Mann-Whitney U test as appropriate. RESULTS: There were no differences between groups in sedation, induction and recovery quality, the median (range) induction dose of alfaxalone [DEX0.5: 2.2 (1.9-2.5) mg kg-1; DEX1: 1.8 (1.2-2.9) mg kg-1], total dose of alfaxalone rescue boluses [DEX0.5: 21.0 (12.5-38.8) mg; DEX1: 22.5 (15.5-30.6) mg] or rate of alfaxalone (DEX0.5: 0.12±0.04 mg kg-1 minute-1; DEX1: 0.12±0.03 mg kg-1 minute-1). CONCLUSIONS AND CLINICAL RELEVANCE: Co-administration of dexmedetomidine 1 µg kg-1 hour-1 failed to reduce the dose rate of alfaxalone compared with dexmedetomidine 0.5 µg kg-1 hour-1 in Greyhounds undergoing laparoscopic ovariohysterectomy. The authors recommend an alfaxalone starting dose rate of 0.1 mg kg-1 minute-1. Recovery quality was good in the majority of dogs.


Assuntos
Anestésicos/farmacologia , Dexmedetomidina/farmacologia , Medicação Pré-Anestésica/veterinária , Pregnanodionas/farmacologia , Anestésicos/administração & dosagem , Animais , Pressão Sanguínea/efeitos dos fármacos , Dexmedetomidina/administração & dosagem , Cães , Feminino , Frequência Cardíaca/efeitos dos fármacos , Histerectomia/veterinária , Metadona/administração & dosagem , Ovariectomia/veterinária , Medicação Pré-Anestésica/métodos , Pregnanodionas/administração & dosagem , Estudos Prospectivos
15.
Eur J Contracept Reprod Health Care ; 22(1): 62-69, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27957867

RESUMO

OBJECTIVES: The aim of the study was to ascertain the influence of knowledge and interventions in sexual and reproductive health and contraception practices among adolescent street girls from Kinshasa, Democratic Republic of the Congo. METHODS: A cross-sectional study was carried out among street girls between 12 and 21 years of age. A standardised questionnaire was used, encompassing socio-demographic data and knowledge and practices regarding sexual and reproductive health. A network analysis was carried out. RESULTS: The study comprised 293 street girls. The mean age was 17.1 years (range 12-21 years) and the mean time spent living on the streets was 3.9 years (range 0-15 years). Commercial sex was reported by 78.5% (95% confidence interval [CI] 73.3%, 83.2%) as the main source of their income. During their last sexual intercourse, 44.0% (95%CI 38.1%, 50.4%) had not used a condom; 29.3% (95%CI 23.3%, 35.9%) had used hormonal contraception. Previous pregnancy was reported by 62.5% (95%CI 56.7%, 68.3%) and current pregnancy by 12.3% (95%CI 8.8%, 17.2%); 24.5% of previous pregnancies ended in voluntary termination, with a higher rate among the youngest street girls (12-15 years, 50.0%; p = 0.01). Time spent living on the streets was independently associated with pregnancy (odds ratio 1.2; 95%CI 1.1, 1.4). Practices and outcomes (previous or current pregnancy) were poorly correlated with knowledge about sexual and reproductive health. The network analysis confirmed the poor influence of exposure to intervention activities on sexual and reproductive health practices and outcomes, but did confirm a centrality effect of knowledge about HIV/AIDS. CONCLUSION: Street girls in Kinshasa are extremely vulnerable with regard to their sexual and reproductive health, especially the youngest street girls. Behavioural and biomedical interventions have had limited influence. Structural and societal changes are necessary to positively impact street girls' sexual and reproductive health. Knowledge about HIV/AIDS than about risk of pregnancy had a greater influence on sexual and reproductive health practices.


Assuntos
Comportamento do Adolescente/psicologia , Comportamento Contraceptivo/psicologia , Conhecimentos, Atitudes e Prática em Saúde , Trabalho Sexual/psicologia , Comportamento Sexual/psicologia , Adolescente , Fatores Etários , Criança , Anticoncepção/métodos , Anticoncepção/psicologia , Anticoncepção/estatística & dados numéricos , Comportamento Contraceptivo/estatística & dados numéricos , Estudos Transversais , República Democrática do Congo , Feminino , Jovens em Situação de Rua/psicologia , Jovens em Situação de Rua/estatística & dados numéricos , Humanos , Gravidez , Gravidez na Adolescência/psicologia , Gravidez na Adolescência/estatística & dados numéricos , Trabalho Sexual/estatística & dados numéricos , Inquéritos e Questionários , Fatores de Tempo , Adulto Jovem
16.
Int J Esthet Dent ; 19(1): 34-44, 2024 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-38284942

RESUMO

OBJECTIVES: The present case report describes the atraumatic extraction of a primary maxillary right canine followed by immediate implant placement with a customized zirconia abutment and monolithic ultra-translucent zirconia (5Y-PSZ) crown. CLINICAL CONSIDERATIONS: A 31-year-old patient presented to the clinic with the primary concern of mobility and gingival inflammation around the maxillary right canine. After clinical evaluation, the tooth was found to be a primary retained tooth that presented grade 3 mobility and gingival inflammation. Atraumatic tooth extraction was performed, followed by immediate implant placement of a screw-retained provisional restoration with the use of a surgical guide. The soft tissue was contoured until ideal architecture was obtained. The final restoration included a customized zirconia and titanium abutment and a characterized implant-supported monolithic 5Y-PSZ crown. CONCLUSIONS: Well-planned surgical and restorative procedures including atraumatic extraction, 3D implant planning for surgical guide fabrication, implant placement, and a customized zirconia abutment with a monolithic 5Y-PSZ crown can achieve high esthetic results in replacing a primary tooth in the esthetic zone.


Assuntos
Implantes Dentários , Gengivite , Zircônio , Humanos , Adulto , Estética Dentária , Coroas , Inflamação
17.
Life Sci Alliance ; 7(8)2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38834194

RESUMO

Vinculin is a cytoskeletal linker strengthening cell adhesion. The Shigella IpaA invasion effector binds to vinculin to promote vinculin supra-activation associated with head-domain-mediated oligomerization. Our study investigates the impact of mutations of vinculin D1D2 subdomains' residues predicted to interact with IpaA VBS3. These mutations affected the rate of D1D2 trimer formation with distinct effects on monomer disappearance, consistent with structural modeling of a closed and open D1D2 conformer induced by IpaA. Notably, mutations targeting the closed D1D2 conformer significantly reduced Shigella invasion of host cells as opposed to mutations targeting the open D1D2 conformer and later stages of vinculin head-domain oligomerization. In contrast, all mutations affected the formation of focal adhesions (FAs), supporting the involvement of vinculin supra-activation in this process. Our findings suggest that IpaA-induced vinculin supra-activation primarily reinforces matrix adhesion in infected cells, rather than promoting bacterial invasion. Consistently, shear stress studies pointed to a key role for IpaA-induced vinculin supra-activation in accelerating and strengthening cell-matrix adhesion.


Assuntos
Adesão Celular , Adesões Focais , Vinculina , Vinculina/metabolismo , Vinculina/genética , Humanos , Adesões Focais/metabolismo , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Mutação , Interações Hospedeiro-Patógeno , Células HeLa , Ligação Proteica , Shigella/metabolismo , Shigella/genética , Antígenos de Bactérias/metabolismo , Antígenos de Bactérias/genética , Disenteria Bacilar/microbiologia , Disenteria Bacilar/metabolismo
18.
Microbiol Spectr ; 11(3): e0458422, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37022279

RESUMO

We characterized five carbapenemase-producing Enterobacterales (CPE) isolates from two health care institutions in Lima, Peru. The isolates were identified as Klebsiella pneumoniae (n = 3), Citrobacter portucalensis (n = 1), and Escherichia coli (n = 1). All were identified as blaOXA-48-like gene carriers using conventional PCR. Whole-genome sequencing found the presence of the blaOXA-181 gene as the only carbapenemase gene in all isolates. Genes associated with resistance to aminoglycosides, quinolones, amphenicols, fosfomycins, macrolides, tetracyclines, sulfonamides, and trimethoprim were also found. The plasmid incompatibility group IncX3 was identified in all genomes in a truncated Tn6361 transposon flanked by ΔIS26 insertion sequences. The qnrS1 gene was also found downstream of blaOXA-181, conferring fluoroquinolone resistance to all isolates. CPE isolates harboring blaOXA-like genes are an increasing public health problem in health care settings worldwide. The IncX3 plasmid is involved in the worldwide dissemination of blaOXA-181, and its presence in these CPE isolates suggests the wide dissemination of blaOXA-181 in Peru. IMPORTANCE Reports of carbapenemase-producing Enterobacterales (CPE) isolates are increasing worldwide. Accurate detection of the ß-lactamase OXA-181 (a variant of OXA-48) is important to initiate therapy and preventive measures in the clinic. OXA-181 has been described in CPE isolates in many countries, often associated with nosocomial outbreaks. However, the circulation of this carbapenemase has yet to be reported in Peru. Here, we report the detection of five multidrug-resistant CPE clinical isolates harboring blaOXA-181 in the IncX3-type plasmid, a potential driver of dissemination in Peru.


Assuntos
Infecções por Enterobacteriaceae , Enterobacteriaceae , Humanos , Enterobacteriaceae/genética , América Latina , Proteínas de Bactérias/genética , beta-Lactamases/genética , Escherichia coli/genética , Klebsiella pneumoniae/genética , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana , Infecções por Enterobacteriaceae/epidemiologia
19.
Lancet Glob Health ; 11 Suppl 1: S21, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36866479

RESUMO

BACKGROUND: Mexico declared an obesity epidemic in 2000, and in response, became an early adopter of public policies in the form of natural experiments, which have not been evaluated for their effect on high BMI. We focus on children younger than 5 years due to the long-term outcomes of childhood obesity. METHODS: We used the Global Burden of Disease data to evaluate time trends in high BMI, defined as being overweight or obese based on the International Obesity Task Force standards, between 1990 and 2019. Marginalisation and poverty estimates from Mexico's Government were used to identify differences in socioeconomic groups. The time variable reflects the introduction of policies between 2006 and 2011. Our hypothesis was that poverty and marginalisation modify the effects of public policies. We tested for the change in prevalence of high BMI over time using Wald-type tests, correcting for the effect of repeated measures. We stratified the sample by gender, marginalisation index, and households under the poverty line. Ethics approval was not required. FINDINGS: Between 1990 and 2019, high BMI in children younger than 5 years increased from 23·5% (95% uncertainty interval 38·6-14·3) to 30·2% (46·0-20·4). After a period of sustained increase to 28·7% (44·8-18·6) in 2005, high BMI decreased to 27·3% (42·4-17·4; p<0·001) in 2011. Afterwards, high BMI increased constantly. We found an average gender gap of 12·2%, with a higher rate in males, in 2006, which remained constant. With respect to marginalisation and poverty, we observed a reduction in high BMI across all strata, except for the uppermost quintile of marginalisation in which high BMI remained flat. INTERPRETATION: The epidemic affected groups across different socioeconomic levels, thus weakening economic explanations for the decrease in high BMI, while gender gaps point to behavioural explanations of consumption. The observed patterns warrant investigation through more granular data and structural models to isolate the effect of the policy from secular trends in the population, including other age groups. FUNDING: Tecnológico de Monterrey Challenge-Based Research Funding Program.


Assuntos
Obesidade Infantil , Criança , Masculino , Humanos , Análise de Séries Temporais Interrompida , Índice de Massa Corporal , México/epidemiologia , Obesidade Infantil/epidemiologia , Obesidade Infantil/prevenção & controle , Política Pública
20.
Sci Rep ; 13(1): 13125, 2023 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-37573373

RESUMO

The concept of "one-airway-one-disease", coined over 20 years ago, may be an over-simplification of the links between allergic diseases. Genomic studies suggest that rhinitis alone and rhinitis with asthma are operated by distinct pathways. In this MeDALL (Mechanisms of the Development of Allergy) study, we leveraged the information of the human interactome to distinguish the molecular mechanisms associated with two phenotypes of allergic rhinitis: rhinitis alone and rhinitis in multimorbidity with asthma. We observed significant differences in the topology of the interactomes and in the pathways associated to each phenotype. In rhinitis alone, identified pathways included cell cycle, cytokine signalling, developmental biology, immune system, metabolism of proteins and signal transduction. In rhinitis and asthma multimorbidity, most pathways were related to signal transduction. The remaining few were related to cytokine signalling, immune system or developmental biology. Toll-like receptors and IL-17-mediated signalling were identified in rhinitis alone, while IL-33 was identified in rhinitis in multimorbidity. On the other hand, few pathways were associated with both phenotypes, most being associated with signal transduction pathways including estrogen-stimulated signalling. The only immune system pathway was FceRI-mediated MAPK activation. In conclusion, our findings suggest that rhinitis alone and rhinitis and asthma multimorbidity should be considered as two distinct diseases.


Assuntos
Asma , Rinite Alérgica , Rinite , Humanos , Multimorbidade , Citocinas
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