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1.
Sci Rep ; 14(1): 6297, 2024 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-38491095

RESUMO

Pseudomonas aeruginosa often colonizes immunocompromised patients, causing acute and chronic infections. This bacterium can reside transiently inside cultured macrophages, but the contribution of the intramacrophic stage during infection remains unclear. MgtC and OprF have been identified as important bacterial factors when P. aeruginosa resides inside cultured macrophages. In this study, we showed that P. aeruginosa mgtC and oprF mutants, particular the latter one, had attenuated virulence in both mouse and zebrafish animal models of acute infection. To further investigate P. aeruginosa pathogenesis in zebrafish at a stage different from acute infection, we monitored bacterial load and visualized fluorescent bacteria in live larvae up to 4 days after infection. Whereas the attenuated phenotype of the oprF mutant was associated with a rapid elimination of bacteria, the mgtC mutant was able to persist at low level, a feature also observed with the wild-type strain in surviving larvae. Interestingly, these persistent bacteria can be visualized in macrophages of zebrafish. In a short-time infection model using a macrophage cell line, electron microscopy revealed that internalized P. aeruginosa wild-type bacteria were either released after macrophage lysis or remained intracellularly, where they were localized in vacuoles or in the cytoplasm. The mgtC mutant could also be detected inside macrophages, but without causing cell damage, whereas the oprF mutant was almost completely eliminated after phagocytosis, or localized in phagolysosomes. Taken together, our results show that the main role of OprF for intramacrophage survival impacts both acute and persistent infection by this bacterium. On the other hand, MgtC plays a clear role in acute infection but is not essential for bacterial persistence, in relation with the finding that the mgtC mutant is not completely eliminated by macrophages.


Assuntos
Proteínas de Bactérias , Infecções por Pseudomonas , Humanos , Animais , Camundongos , Proteínas de Bactérias/metabolismo , Peixe-Zebra/metabolismo , Infecções por Pseudomonas/genética , Fagocitose , Fagossomos/metabolismo , Pseudomonas aeruginosa/metabolismo
2.
Obes Sci Pract ; 10(2): e743, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38414573

RESUMO

Background: Orforglipron is a novel once-daily oral non-peptide glucagon-like peptide-1 receptor agonist with several recently published randomized controlled trials (RCTs) evaluating its role in diabetes and obesity. No meta-analysis has analyzed the efficacy and safety of orforglipron; this meta-analysis aimed to address this knowledge gap. Methods: A systematic search was conducted in electronic databases to identify RCTs that included individuals with obesity who were administered orforglipron and compared to either a placebo or an active comparator. The primary outcome of interest was the percent change in body weight. Results: From 12 initially screened articles, data from three RCTs involving 774 people were analyzed with a follow-up duration of up to 36 weeks. Compared to placebo, patients receiving orforglipron 12 mg/day (mean difference (MD), MD -5.48%, 95% CI [-7.64, -3.33], p < 0.01), 24 mg/day (MD -8.51%, 95% confidence interval (CI) [-9.88, -7.14], p < 0.01), 36 mg/day (MD -8.84%, 95% CI [-11.68, -6.00], p < 0.01) and 45 mg/day (MD -8.24%, 95% CI [-12.84, -3.63], p < 0.01) had a significantly greater percent reduction in body weight. The percentage of patients being able to achieve >15% weight loss from baseline was significantly higher with orforglipron 24 mg/day [Odds ratio (OR) 21.90 (95% CI [4.06, 118.15], p = 0.0003), 36 mg/day (OR 17.43, 95% CI [3.18, 95.66], p = 0.001) and 45 mg/day (OR 23.17, 95% CI [4.37, 123.03], p = 0.0002). Total but not severe adverse events were significantly higher with all the doses of orforglipron compared to placebo, with the hazard ratios being higher with higher doses. Gastrointestinal side-effects were predominant side effects, being dose-dependent, with nausea, vomiting, constipation, and gastroesophageal reflux being the predominant ones. Conclusion: Orforglipron at 24-45 mg/day doses is an effective weight loss medication. The efficacy versus side effect profile suggests that 24-36 mg/day is the most optimal dose for orforglipron as an anti-obesity medicine.

3.
BMJ Case Rep ; 17(2)2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38331444

RESUMO

A child, who was reared as male, presented in his early childhood to the endocrine clinic with penoscrotal hypospadias which was noticed at birth. On examination, he had both gonads in the scrotal sacs with complete scrotal fusion, rugosities and chordee with a single opening. He had increased palmoplantar skin desquamation. As an initial part of the workup, karyotyping was done, which was 46,XX. To rule out the most common cause of 46,XX disorder of sex development (DSD) in phenotypical males (SRY - Sex Determining Region Y gene - translocation), fluorescent in situ hybridisation for SRY was done, which was negative. Whole exome sequencing revealed a homozygous loss of function mutation in the R-Spondin1 gene. Here we report a rare case of 46,XX DSD with loss of function mutation in the R-Spondin1 gene associated with skin abnormalities.


Assuntos
Transtornos do Desenvolvimento Sexual , Anormalidades da Pele , Pré-Escolar , Humanos , Masculino , Cariotipagem , Mutação com Perda de Função , Mutação , Desenvolvimento Sexual
5.
Am J Hematol ; 98(10): 1559-1570, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37483161

RESUMO

Complement activation has shown a role in murine models of graft-versus-host disease (GVHD) and in endothelial complications after allogeneic hematopoietic cell transplantation (allo-HSCT). However, its impact on post-transplant outcomes has not been so far fully elucidated. Here, we conducted a prospective multicentric trial (NCT01520623) performing serial measurements of complement proteins, regulators, and CH50 activity for 12 weeks after allo-HSCT in 85 patients receiving a myeloablative conditioning (MAC) regimen for various hematological malignancies. Twenty-six out of 85 patients showed an "activated" complement profile through the classical/lectin pathway, defined as a post-transplant decline of C3/C4 and CH50 activity. Time-dependent Cox regression models demonstrated that complement activation within the first weeks after allo-HSCT was associated with increased non-relapse mortality (hazard ratio [HR]: 3.69, 95% confident interval [CI]: 1.55-8.78, p = .003) and poorer overall survival (HR: 2.72, 95% CI: 1.37-5.39, p = .004) due to increased incidence of grade II-IV acute GVHD and in particular gastrointestinal (GI) GVHD (HR: 36.8, 95% CI: 12.4-109.1, p < .001), higher incidences of thrombotic microangiopathy (HR: 8.58, 95% CI: 2.16-34.08, p = .0022), capillary leak syndrome (HR: 7.36, 95% CI: 2.51-21.66, p = .00028), post-engraftment bacterial infections (HR: 2.37, 95% CI: 1.22-4.63, p = .0108), and EBV reactivation (HR: 3.33, 95% CI: 1.31-8.45, p = .0112). Through specific immune staining, we showed the correlation of deposition of C1q, C3d, C4d, and of C5b9 components on endothelial cells in GI GVHD lesions with the histological grade of GVHD. Altogether these findings define the epidemiology and the clinical impact of complement classical/lectin pathway activation after MAC regimens and provide a rational for the use of complement inhibitory therapeutics in a post-allo-HSCT setting.


Assuntos
Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Humanos , Animais , Camundongos , Células Endoteliais/patologia , Estudos Prospectivos , Recidiva Local de Neoplasia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Ativação do Complemento , Condicionamento Pré-Transplante/efeitos adversos , Estudos Retrospectivos
6.
Diabetes Metab Syndr ; 17(8): 102816, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37421885

RESUMO

BACKGROUND: Enavogliflozin is a novel sodium glucose co-transporter-2 inhibitor (SGLT2i) developed in South Korea. This meta-analysis was done as no meta-analysis has analysed the efficacy and safety of enavogliflozin in type-2 diabetes (T2DM). METHODS: Electronic databases were systematically reviewed for randomized controlled trials having patients with T2DM receiving enavogliflozin in treatment-arm, and placebo/any other medicine in control-arm. Primary outcome was to evaluate changes in glycosylated haemoglobin (HbA1C). Secondary outcomes were to evaluate alterations in fasting glucose (FPG), 2-h post prandial glucose (2-h PPG), blood pressure (BP), weight, lipids, and adverse events. RESULTS: Data from 4 trials (684 patients) was analysed for clinical outcomes over 12-24 weeks clinical use. Compared to placebo, patients receiving enavogliflozin had significantly lower HbA1c [MD -0.76%(95% CI: 0.93 to -0.60); P < 0.00001; I2 = 97%], FPG [MD -2.12 mmol/l(95%CI: 2.47 to -1.77); P < 0.00001; I2 = 91%], body-weight [MD-1.37 kgs (95% CI: 1.73-1.00); P < 0.00001; I2 = 89%], systolic BP [MD-4.99 mm Hg (95%CI: 7.83 to -2.16); P = 0.0006; I2 = 47%], diastolic BP [MD-3.09 mm Hg(95%CI: 3.38 to -2.81); P < 0.00001; I2 = 0%]. Treatment emergent adverse-events [OR1.16(95%CI:0.64-2.09); P = 0.63; I2 = 0%], serious adverse events [OR1.81(95%CI:0.37-8.83); P = 0.46; I2 = 0%], urinary infections [OR1.37(95%CI:0.09-20.61); P = 0.82; I2 = 33%] and genital infections [OR 3.07(95%CI:0.31-29.88); P = 0.33; I2 = 0%] were comparable. Compared to dapagliflozin, patients receiving enavogliflozin had significantly lower HbA1c [MD-0.06%(95%CI: 0.07-0.05); P < 0.00001; I2 = 0%], FPG [MD-0.19 mmol/l(95%CI: 0.21 to -0.17); P < 0.00001; I2 = 0%], body-weight [MD-0.20 kgs(95%CI: 0.24 to -0.15); P < 0.00001; I2 = 0%], diastolic BP [MD -0.92 mm Hg (95%CI: 1.36 to -0.48); P < 0.0001; I2 = 91%] and significantly higher urine glucose creatinine ratio [MD 16.69 g/g (95%CI:16.11-17.26); P < 0.00001; I2 = 0%]. CONCLUSION: Enavogliflozin is a well tolerated and effective SGLT2i for T2DM and may be superior to dapagliflozin with regard to certain clinical aspects over 6 months clinical use.


Assuntos
Diabetes Mellitus Tipo 2 , Inibidores do Transportador 2 de Sódio-Glicose , Simportadores , Humanos , Inibidores do Transportador 2 de Sódio-Glicose/efeitos adversos , Hipoglicemiantes/uso terapêutico , Hemoglobinas Glicadas , Diabetes Mellitus Tipo 2/complicações , Glucose , Simportadores/uso terapêutico , Sódio/uso terapêutico , Glicemia
7.
Br J Haematol ; 202(1): 122-134, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37092504

RESUMO

An efficient immunological reconstitution construes the pillar for the success of allogeneic haematopoietic cell transplantation (HCT) in haematological disorders. Factors influencing post-transplant immune recovery have been largely investigated across multiple cohorts issuing heterogeneous results. Differences in outcomes in adult and paediatric populations suggest an age-related contribution to post-transplant immune reconstitution; however, it is unclear how recipient and donor age may affect the dynamics of single immune cells. Here, we retrospectively collected and analysed immunological data of 174 patients (58 children and 116 adults) consecutively transplanted for haematological disorders in our centre. We show that trajectories of specific immune cells were strictly dependent on recipient age and pretransplant virus exposure, with the strongest effect seen on T CD4+ and B-cell counterparts, while donor age and transplant platforms had a minimal impact. This mirrored different kinetics of immune reconstitution in adult and paediatric patients, with major divergences in immune cell composition in late post-transplant phases, featuring better survival, relapse-free survival and cumulative incidence of pathogen-specific infections in younger patients. Altogether, these findings underpin the importance of recipient age on post-transplant immune cell recovery and define the basic dynamics of the immune reconstitution in paediatric and adult populations as a benchmark for future studies.


Assuntos
Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Adulto , Humanos , Criança , Estudos Retrospectivos , Transplante Homólogo/efeitos adversos , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Linfócitos B , Doença Enxerto-Hospedeiro/etiologia
8.
Int J Diabetes Dev Ctries ; : 1-7, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36684486

RESUMO

Introduction: Respiratory infections like influenza and pneumococcus increase mortality, morbidity, hospitalisation risks and healthcare costs in people with type 2 diabetes which can be prevented by vaccinations. However, there is not much data regarding how many people with type 2 diabetes in India receive pneumococcal and influenza vaccinations. Methods: This is a cross-sectional study conducted between March 2022 to May 2022 at a tertiary care centre in South India. Patients were interviewed through face to face questionnaire regarding awareness, knowledge of influenza and pneumococcal infections, availability and need of vaccines, vaccination status and the possible reasons for not receiving vaccines. Results: A total of 388 patients were recruited in the study. Knowledge about influenza and pneumococcal infections were present only in 4.8% and 4.1% respectively. And 98.7% of patients had no awareness about the availability and need for vaccines. Only 0.5% and 0.7% of patients received influenza and pneumococcal vaccinations respectively. After counselling and spreading awareness, 76.2% of patients said that they would receive vaccination in the next visit. Also, 23.19% of the patients refused to take any vaccinations even after counselling. And 23.7% of patients feared complications after vaccinations. Conclusion: Pneumococcal and Influenza vaccination uptake rates are extremely low in people with type 2 diabetes in India. Urgent measures are required to increase the awareness in patients and healthcare workers about the availability, need for vaccinations and effectiveness of vaccines which would lead to improvement in vaccination rates.

10.
Soins Gerontol ; 28(159): 36-41, 2023.
Artigo em Francês | MEDLINE | ID: mdl-36717176

RESUMO

In order to improve the cognitive-behavioral pathway, and based on a well-established history of city-hospital collaboration, a monthly staff meeting bringing together hospital and out-of-hospital professionals and a users' association makes it possible to analyze and respond in a coordinated and graduated manner to complex situations. After nine months of operation, the story of three complex situations illustrates the benefits and limits of such a system.


Assuntos
Cognição , Recursos Humanos em Hospital , Humanos
11.
FEBS J ; 290(2): 482-501, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36036789

RESUMO

Multidrug resistance is a major public health problem that requires the urgent development of new antibiotics and therefore the identification of novel bacterial targets. The activity of nicotinamide adenine dinucleotide kinase, NADK, is essential in all bacteria tested so far, including many human pathogens that display antibiotic resistance leading to the failure of current treatments. Inhibiting NADK is therefore a promising and innovative antibacterial strategy since there is currently no drug on the market targeting this enzyme. Through a fragment-based drug design approach, we have recently developed a NAD+ -competitive inhibitor of NADKs, which displayed in vivo activity against Staphylococcus aureus. Here, we show that this compound, a di-adenosine derivative, is inactive against the NADK enzyme from the Gram-negative bacteria Pseudomonas aeruginosa (PaNADK). This lack of activity can be explained by the crystal structure of PaNADK, which was determined in complex with NADP+ in this study. Structural analysis led us to design and synthesize a benzamide adenine dinucleoside analogue, active against PaNADK. This novel compound efficiently inhibited PaNADK enzymatic activity in vitro with a Ki of 4.6 µm. Moreover, this compound reduced P. aeruginosa infection in vivo in a zebrafish model.


Assuntos
Antibacterianos , NAD , Pseudomonas aeruginosa , Animais , Antibacterianos/farmacologia , Antibacterianos/química , NAD/análogos & derivados , Fosfotransferases (Aceptor do Grupo Álcool) , Pseudomonas aeruginosa/efeitos dos fármacos , Peixe-Zebra , Desenho de Fármacos
12.
World J Clin Cases ; 10(17): 5702-5707, 2022 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-35979111

RESUMO

BACKGROUND: Patients with paroxysmal nocturnal hemoglobinuria (PNH) have a clonal population of blood cells deficient in glycosylphosphatidylinositol-anchored (GPI-anchored) proteins, most of the time resulting from a mutation in the X-linked gene PIGA. We report a patient with PNH resulting from a rare biallelic PIGT mutation on chromosome 20. CASE SUMMARY: A 47-year-old man was referred to our hospital for febrile pancytopenia. The patient reported a history of recurrent urticaria and arthralgia and he presented during 3 mo recurrent acute dermo-hypodermitis and aseptic meningitidis. Based on clinical cases published with PIGT-PNH, with clinically typical PNH and autoinflammatory symptoms, we treated our patients with repeated infusions of eculizumab to decrease autoinflammatory symptoms and then we performed an allogeneic stem cell transplantation (allo-SCT) with a mismatched unrelated donor. Our patient experienced no acute Graft vs Host disease (GvHD) and a moderate chronic GvHD and is now considered cured at 24 mo after allo-SCT. CONCLUSION: This case report suggests that allo-SCT should be considered to cure PIGT-PNH patients.

13.
J Cell Mol Med ; 26(5): 1339-1350, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35088933

RESUMO

For decades, mesenchymal stromal cells (MSCs) have been of great interest in the fields of regenerative medicine, tissue engineering and immunomodulation. Their tremendous potential makes it desirable to cryopreserve and bank MSCs to increase their accessibility and availability. Postnatally derived MSCs seem to be of particular interest because they are harvested after delivery without ethical controversy, they have the capacity to expand at a higher rate than adult-derived MSCs, in which expansion decreases with ageing, and they have demonstrated immunological and haematological supportive properties similar to those of adult-derived MSCs. In this review, we focus on MSCs obtained from Wharton's jelly (the mucous connective tissue of the umbilical cord between the amniotic epithelium and the umbilical vessels). Wharton's jelly MSCs (WJ-MSCs) are a good candidate for cellular therapy in haematology, with accumulating data supporting their potential to sustain haematopoietic stem cell engraftment and to modulate alloreactivity such as Graft Versus Host Disease (GVHD). We first present an overview of their in-vitro properties and the results of preclinical murine models confirming the suitability of WJ-MSCs for cellular therapy in haematology. Next, we focus on clinical trials and discuss tolerance, efficacy and infusion protocols reported in haematology for GVHD and engraftment.


Assuntos
Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Geleia de Wharton , Animais , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Camundongos , Cordão Umbilical
14.
J Pak Med Assoc ; 72(11): 2332-2334, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37013318

RESUMO

Diabetes is a significant risk factor for coronavirus disease 2019 (COVID-19) severity, poor prognosis, and mortality. Uncontrolled hyperglycaemia is associated with impaired innate and adaptive immunity predisposing to severe infection. In addition, there are other mechanisms linked to diabetes such as the upregulation of angiotensin-converting enzyme-2 receptor that might aid in viral entry and spread. The chronic low-grade inflammation and endothelial dysfunction might provide the backdrop to the development of cytokine storm and thromboembolic complications. Understanding the pathophysiology behind severe COVID-19 in diabetes will help to optimise management.


Assuntos
COVID-19 , Diabetes Mellitus , Humanos , SARS-CoV-2 , Diabetes Mellitus/epidemiologia , Inflamação , Fatores de Risco
15.
Antibiotics (Basel) ; 10(12)2021 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-34943755

RESUMO

Escherichia coli isolated from meat of different animal species may harbour antimicrobial resistance genes and may thus be a threat to human health. The objectives of this study were to define antimicrobial resistance genes in E. coli isolates from pork, beef, chicken- and turkey meat and analyse whether their resistance genotypes associated with phylogenetic groups or meat species. A total number of 313 E. coli samples were isolated using standard cultural techniques. In 98% of resistant isolates, a dedicated resistance gene could be identified by PCR. Resistance genes detected were tet(A) and tet(B) for tetracycline resistance, strA and aadA1 for streptomycin resistance, sulI and sulII for resistance against sulphonamides, dfr and aphA for kanamycin resistance and blaTEM for ampicillin resistance. One stx1 harbouring E. coli isolated from pork harboured the tet(A) gene and belonged to phylogenetic group B2, whilst another stx1 positive isolate from beef was multi-resistant and tested positive for blaTEM,aphA, strA-B, sulII, and tet(A) and belonged to phylogenetic group A. In conclusion, the distribution of resistance elements was almost identical and statistically indifferent in isolates of different meat species. Phylogenetic groups did not associate with the distribution of resistance genes and a rather low number of diverse resistance genes were detected. Most E. coli populations with different resistance genes against one drug often revealed statistically significant different MIC values.

16.
Clin Pract ; 11(4): 850-859, 2021 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-34842637

RESUMO

Type 2 diabetes mellitus (T2DM) is a chronic progressive disorder and is associated with significant morbidity and mortality. The concept of T2DM remission and the reversal of diabetic parameters to normal levels has been gaining momentum over the past years. T2DM remission is increasingly being recognized by various global guidelines. Multiple models have been developed and validated for quantifying the extent of remission achieved. Based on favorable clinical evidence, T2DM remission can be considered as the therapeutic goal in diabetes management and, in select cases, as an alternative to expensive treatment options, which can be burdensome as T2DM progresses. This narrative review discusses the available strategies, such as lifestyle interventions, physical activity, bariatric surgery, medical nutrition therapy, and non-insulin glucose-lowering medications, for achieving T2DM remission. Although the concept of T2DM remission has emerged as a real-world option, effective implementation in routine clinical practice may not be feasible until long-term studies prove the efficacy of different approaches in this regard.

17.
Indian J Endocrinol Metab ; 25(2): 95-102, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34660237

RESUMO

BACKGROUND: Pituitary dysfunction following severe traumatic brain injury (sTBI) is significant and may be correlated with the outcomes. AIMS AND OBJECTIVES: This study aimed to evaluate the early changes in pituitary hormone levels after sTBI and to correlate with outcomes in terms of severity and mortality. METHODS: This was a prospective, observational study, involving consecutive patients of 16-60 years, with sTBI (Glasgow Coma Scale GCS < 9) presenting to the hospital within 24 h of trauma. Demographic and clinical data were collected. Serum samples were collected in the morning (08-10 am) on day 1 and day 4 for cortisol, thyroid-stimulating hormone (TSH), triiodothyronine (T3), thyroxine (T4), and prolactin (Chemiluminescence immunoassay). Outcome was assessed in terms of mortality (which included both immediate and at 3 months) and Glasgow outcome scale at 3 months. RESULTS: 54 patients were studied. Mean cortisol on day 4 was 28.5 µg/dL in alive patients and 13.7 µg/dL in patients deceased at 3 months (P < 0.001). Patients who were deceased at 3 months had significantly lower T3 on day 4 (0.973 vs 1.4 ng/dL) and lower T4 (8.1 µg/L vs 6.1 µg/dL) as compared to patients who survived (P = 0.049 and 0.005, respectively). Acute phase TSH on day 4 levels were significantly lower in patients deceased at 3 months. There was no significant difference in the prolactin levels. CONCLUSION: Day 4 cortisol, T3, T4, and TSH correlated with the outcomes at 3 months and hence have predictive value post-sTBI.

18.
Front Cell Infect Microbiol ; 11: 745851, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34660345

RESUMO

The opportunistic human pathogen Pseudomonas aeruginosa is responsible for a variety of acute infections and is a major cause of mortality in chronically infected patients with cystic fibrosis (CF). Considering the intrinsic and acquired resistance of P. aeruginosa to currently used antibiotics, new therapeutic strategies against this pathogen are urgently needed. Whereas virulence factors of P. aeruginosa are well characterized, the interplay between P. aeruginosa and the innate immune response during infection remains unclear. Zebrafish embryo is now firmly established as a potent vertebrate model for the study of infectious human diseases, due to strong similarities of its innate immune system with that of humans and the unprecedented possibilities of non-invasive real-time imaging. This model has been successfully developed to investigate the contribution of bacterial and host factors involved in P. aeruginosa pathogenesis, as well as rapidly assess the efficacy of anti-Pseudomonas molecules. Importantly, zebrafish embryo appears as the state-of-the-art model to address in vivo the contribution of innate immunity in the outcome of P. aeruginosa infection. Of interest, is the finding that the zebrafish encodes a CFTR channel closely related to human CFTR, which allowed to develop a model to address P. aeruginosa pathogenesis, innate immune response, and treatment evaluation in a CF context.


Assuntos
Fibrose Cística , Infecções por Pseudomonas , Animais , Fibrose Cística/complicações , Humanos , Imunidade Inata , Infecções por Pseudomonas/tratamento farmacológico , Pseudomonas aeruginosa , Peixe-Zebra
20.
Evolution ; 75(11): 2911-2929, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34396530

RESUMO

Phenotypic variation is the raw material of evolution. Standing variation can facilitate response to selection along "lines of least evolutionary resistance", but selection itself might alter the structure of the variance. Shape was quantified using 2D geometric morphometrics in Palmatolepis conodonts through the Late Devonian period. Patterns of variance were characterized along the record by the variance-covariance matrix (P-matrix) and its first axis (Pmax). The Late Frasnian was marked by environmental oscillations culminating with the Frasnian/Famennian mass extinction. A shape response was associated with these fluctuations, together with a deflection of the Pmax and the P-matrix. Thereafter, along the Famennian, Palmatolepis mean shape shifted from broad elements with a large platform to slender elements devoid of platform. This shift in shape was associated with a reorientation of Pmax and the P-matrix, due to profound changes in the functioning of the elements selecting for new types of variants. Both cases provide empirical evidences that moving adaptive optimum can reorient phenotypic variation, boosting response to environmental changes. On such time scales, the question seems thus not to be whether the P-matrix is stable, but how it is varying in response to changes in selection regimes and shifts in adaptive optimum.

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