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1.
World J Urol ; 42(1): 177, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38507109

RESUMO

PURPOSE: Diagnostic ureteroscopy (dURS) is optional in the assessment of patients with upper tract urothelial carcinoma (UTUC) and provides the possibility of obtaining histology. METHODS: To evaluate endoscopic biopsy techniques and outcomes, we assessed data from patients from the CROES-UTUC registry. The registry includes multicenter prospective collected data on diagnosis and management of patients suspected having UTUC. RESULTS: We assessed 2380 patients from 101 centers. dURS with biopsy was performed in 31.6% of patients. The quality of samples was sufficient for diagnosis in 83.5% of cases. There was no significant association between biopsy techniques and quality (p = 0.458). High-grade biopsy accurately predicted high-grade disease in 95.7% and high-risk stage disease in 86%. In ureteroscopic low-grade tumours, the prediction of subsequent low-grade disease was 66.9% and low-risk stage Ta-disease 35.8%. Ureteroscopic staging correctly predicted non-invasive Ta-disease and ≥ T1 disease in 48.9% and 47.9% of patients, respectively. Cytology outcomes did not provide additional value in predicting tumour grade. CONCLUSION: Biopsy results adequately predict high-grade and high-risk disease, but approximately one-third of patients are under-staged. Two-thirds of patients with low-grade URS-biopsy have high-risk stage disease, highlighting the need for improved diagnostics to better assess patient risk and guide treatment decisions. CLINICAL TRIAL REGISTRATION: The study was registered at ClinicalTrials.gov (ClinicalTrials.gov NCT02281188; https://clinicaltrials.gov/ct2/show/NCT02281188 ).


Assuntos
Carcinoma de Células de Transição , Neoplasias Renais , Neoplasias Ureterais , Neoplasias da Bexiga Urinária , Humanos , Carcinoma de Células de Transição/diagnóstico , Carcinoma de Células de Transição/patologia , Neoplasias Ureterais/diagnóstico , Neoplasias Ureterais/patologia , Estudos Prospectivos , Ureteroscopia/métodos , Biópsia , Neoplasias Renais/diagnóstico , Neoplasias Renais/patologia
2.
Diagnostics (Basel) ; 13(17)2023 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-37685281

RESUMO

The incidence of renal mass detection has increased during recent decades, with an increased diagnosis of small renal masses, and a final benign diagnosis in some cases. To avoid unnecessary surgeries, there is an increasing interest in using radiomics tools to predict histological results, using radiological features. We performed a narrative review to evaluate the use of radiomics in renal mass characterization. Conventional images, such as computed tomography (CT) and magnetic resonance (MR), are the most common diagnostic tools in renal mass characterization. Distinguishing between benign and malignant tumors in small renal masses can be challenging using conventional methods. To improve subjective evaluation, the interest in using radiomics to obtain quantitative parameters from medical images has increased. Several studies have assessed this novel tool for renal mass characterization, comparing its ability to distinguish benign to malign tumors, the results in differentiating renal cell carcinoma subtypes, or the correlation with prognostic features, with other methods. In several studies, radiomic tools have shown a good accuracy in characterizing renal mass lesions. However, due to the heterogeneity in the radiomic model building, prospective and external validated studies are needed.

3.
Chem Asian J ; 18(19): e202300637, 2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37616375

RESUMO

We present the design and synthesis of artificial specific nucleobases, each one recognizing a single base pair within the major groove of duplex DNA. Computational calculations indicate that PNAs modified with these nucleobases enable the formation of highly stable triple helices with no sequence restrictions through multiple hydrogen bonding and π⋅⋅⋅π stacking interactions, without significantly widening the DNA double helix. New synthetic routes were developed to the structures of these fused heterocycles which have rarely been described in the literature. NMR titration experiments indicate specific hydrogen bonding at the Hoogsteen sites. The new building blocks allow the construction of four PNA monomers for each canonic base pair and their covalent connection to PNA oligomers. These can be designed complementary to any given DNA sequence. With high efficiency and relative simplicity of operation, the described methodologies and strategies hence form the basis for a new supramolecular ligand system targeting double-stranded DNA without strand invasion.

5.
Alzheimers Res Ther ; 15(1): 105, 2023 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-37287063

RESUMO

BACKGROUND: Over recent years, increasing evidence suggests a causal relationship between neurofibrillary tangles (NFTs) formation, the main histopathological hallmark of tauopathies, including Alzheimer's disease (AD), and the ubiquitin-proteasome system (UPS) dysfunction detected in these patients. Nevertheless, the mechanisms underlying UPS failure and the factors involved remain poorly understood. Given that AD and tauopathies are associated with chronic neuroinflammation, here, we explore if ATP, one of the danger-associated molecules patterns (DAMPs) associated with neuroinflammation, impacts on AD-associated UPS dysfunction. METHODS: To evaluate if ATP may modulate the UPS via its selective P2X7 receptor, we combined in vitro and in vivo approaches using both pharmacological and genetic tools. We analyze postmortem samples from human AD patients and P301S mice, a mouse model that mimics pathology observed in AD patients, and those from the new transgenic mouse lines generated, such as P301S mice expressing the UPS reporter UbG76V-YFP or P301S deficient of P2X7R. RESULTS: We describe for the first time that extracellular ATP-induced activation of the purinergic P2X7 receptor (P2X7R) downregulates the transcription of ß5 and ß1 proteasomal catalytic subunits via the PI3K/Akt/GSK3/Nfr2 pathway, leading to their deficient assembly into the 20S core proteasomal complex, resulting in a reduced proteasomal chymotrypsin-like and postglutamyl-like activities. Using UPS-reported mice (UbGFP mice), we identified neurons and microglial cells as the most sensitive cell linages to a P2X7R-mediated UPS regulation. In vivo pharmacological or genetic P2X7R blockade reverted the proteasomal impairment developed by P301S mice, which mimics that were detected in AD patients. Finally, the generation of P301S;UbGFP mice allowed us to identify those hippocampal cells more sensitive to UPS impairment and demonstrate that the pharmacological or genetic blockade of P2X7R promotes their survival. CONCLUSIONS: Our work demonstrates the sustained and aberrant activation of P2X7R caused by Tau-induced neuroinflammation contributes to the UPS dysfunction and subsequent neuronal death associated with AD, especially in the hippocampus.


Assuntos
Doença de Alzheimer , Tauopatias , Camundongos , Humanos , Animais , Doença de Alzheimer/complicações , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Complexo de Endopeptidases do Proteassoma , Receptores Purinérgicos P2X7/genética , Ubiquitina , Doenças Neuroinflamatórias , Quinase 3 da Glicogênio Sintase/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Camundongos Transgênicos , Trifosfato de Adenosina/metabolismo
6.
J Extracell Vesicles ; 12(6): e12333, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37328936

RESUMO

Cell proteostasis includes gene transcription, protein translation, folding of de novo proteins, post-translational modifications, secretion, degradation and recycling. By profiling the proteome of extracellular vesicles (EVs) from T cells, we have found the chaperonin complex CCT, involved in the correct folding of particular proteins. By limiting CCT cell-content by siRNA, cells undergo altered lipid composition and metabolic rewiring towards a lipid-dependent metabolism, with increased activity of peroxisomes and mitochondria. This is due to dysregulation of the dynamics of interorganelle contacts between lipid droplets, mitochondria, peroxisomes and the endolysosomal system. This process accelerates the biogenesis of multivesicular bodies leading to higher EV production through the dynamic regulation of microtubule-based kinesin motors. These findings connect proteostasis with lipid metabolism through an unexpected role of CCT.


Assuntos
Vesículas Extracelulares , Cinesinas , Cinesinas/metabolismo , Chaperonina com TCP-1/metabolismo , Vesículas Extracelulares/metabolismo , Metabolismo dos Lipídeos , Lipídeos
7.
Proc Biol Sci ; 290(1997): 20230030, 2023 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-37122250

RESUMO

Tsetse flies significantly impact public health and economic development in sub-Saharan African countries by transmitting the fatal disease African trypanosomiasis. Unusually, instead of laying eggs, tsetse birth a single larva that immediately burrows into the soil to pupate. Where the female chooses to larviposit is, therefore, crucial for offspring survival. Previous laboratory studies suggested that a putative larval pheromone, n-pentadecane, attracts gravid female Glossina morsitans morsitans to appropriate larviposition sites. However, this attraction could not be reproduced in field experiments. Here, we resolve this disparity by designing naturalistic laboratory experiments that closely mimic the physical characteristics found in the wild. We show that gravid G. m. morsitans were neither attracted to the putative pheromone nor, interestingly, to pupae placed in the soil. By contrast, females appear to choose larviposition sites based on environmental substrate cues. We conclude that, among the many cues that likely contribute to larviposition choice in nature, substrate features are a main determinant, while we failed to find evidence for a role of pheromones.


Assuntos
Moscas Tsé-Tsé , Animais , Feminino , Gravidez , Feromônios , Sinais (Psicologia) , Parto , Larva
8.
Trans R Soc Trop Med Hyg ; 117(9): 609-616, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37103337

RESUMO

Cutaneous leishmaniasis (CL) is a parasitic vector-borne disease affecting mostly low- and middle-income countries. CL is endemic in Guatemala, where an increase in the number of cases and incidence and a changing disease distribution in the past decade have been reported. Important research was conducted in Guatemala in the 1980s and 1990s to understand the epidemiology of CL and two Leishmania species were identified as the aetiologic agents. Several species of sand flies have been reported, five of which are naturally infected with Leishmania. Clinical trials conducted in the country evaluated different treatments against the disease and provided solid evidence for CL control strategies that are applicable worldwide. More recently, in the 2000s and 2010s, qualitative surveys were conducted to understand community perceptions of the disease and to highlight the challenges and enablers for disease control. However, limited recent data have been generated regarding the current CL situation in Guatemala, and key information necessary for effective disease control, such as incrimination of vectors and reservoirs, is still lacking. This review describes the current state of knowledge of CL in Guatemala, including the main parasite and sand fly species, disease reservoirs, diagnosis and control, as well as the perceptions of communities in endemic regions.


Assuntos
Leishmania , Leishmaniose Cutânea , Leishmaniose , Phlebotomus , Psychodidae , Animais , Guatemala/epidemiologia , Leishmaniose Cutânea/epidemiologia , Phlebotomus/parasitologia , Psychodidae/parasitologia
9.
PLoS Pathog ; 19(3): e1011269, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36996244

RESUMO

Trypanosoma brucei spp. develop into mammalian-infectious metacyclic trypomastigotes inside tsetse salivary glands. Besides acquiring a variant surface glycoprotein (VSG) coat, little is known about the metacyclic expression of invariant surface antigens. Proteomic analyses of saliva from T. brucei-infected tsetse flies identified, in addition to VSG and Brucei Alanine-Rich Protein (BARP) peptides, a family of glycosylphosphatidylinositol (GPI)-anchored surface proteins herein named as Metacyclic Invariant Surface Proteins (MISP) because of its predominant expression on the surface of metacyclic trypomastigotes. The MISP family is encoded by five paralog genes with >80% protein identity, which are exclusively expressed by salivary gland stages of the parasite and peak in metacyclic stage, as shown by confocal microscopy and immuno-high resolution scanning electron microscopy. Crystallographic analysis of a MISP isoform (MISP360) and a high confidence model of BARP revealed a triple helical bundle architecture commonly found in other trypanosome surface proteins. Molecular modelling combined with live fluorescent microscopy suggests that MISP N-termini are potentially extended above the metacyclic VSG coat, and thus could be tested as a transmission-blocking vaccine target. However, vaccination with recombinant MISP360 isoform did not protect mice against a T. brucei infectious tsetse bite. Lastly, both CRISPR-Cas9-driven knock out and RNAi knock down of all MISP paralogues suggest they are not essential for parasite development in the tsetse vector. We suggest MISP may be relevant during trypanosome transmission or establishment in the vertebrate's skin.


Assuntos
Parasitos , Trypanosoma brucei brucei , Trypanosoma , Animais , Camundongos , Trypanosoma brucei brucei/genética , Proteínas de Membrana , Alanina , Proteômica , Glândulas Salivares/parasitologia , Mamíferos , Glicoproteínas de Membrana
10.
Rev. colomb. neumol ; 34(2): 17-24, July-Dec. 2022.
Artigo em Espanhol | LILACS, COLNAL | ID: biblio-1412682

RESUMO

Introducción: la enfermedad por COVID-19 puede provocar una gran variedad de problemas de salud a largo plazo, como deterioro de la función pulmonar, reducción del rendimiento del ejercicio y disminución de la calidad de vida. Nuestro estudio tuvo como objetivo investigar la eficacia, viabilidad y seguridad de la rehabilitación pulmonar en pacientes con COVID-19 y comparar los resultados entre pacientes con un curso leve/moderado y grave/crítico de la enfermedad. Material y métodos: los pacientes en la fase posaguda de un curso leve a crítico de COVID-19 ingresados en un programa integral de rehabilitación pulmonar, se incluyeron en este estudio de cohorte prospectivo y observacional. Se evaluaron antes y después varias medidas de rendimiento del ejercicio, distancia de caminata de 6 minutos, función pulmonar (capacidad vital forzada (CVF)) y calidad de vida (encuesta de salud de formato corto de 36 preguntas (SF-36)). Se incluyeron 43 pacientes en el estudio (20 con COVID leve/moderado y 23 con COVID grave/crítico). Resultados: al ingreso los pacientes tenían una distancia de caminata reducida (leve: mediana 401 m, rango intercuartílico (IQR) 335-467 m; severo: 108 m, 84-132 m); una CVF deteriorada (leve: 72 %, severo: 35 %), y una puntuación baja de salud mental SF-36 (leve: 52 puntos, severo: 32 puntos. Los pacientes recibieron sesiones ajustadas a sus capacidades físicas y en ambos subgrupos mejoraron en la prueba de caminata de 6 minutos (leve/moderada: +54 m, severo/crítico: +117 m, ambos p <0.002), en CVF (leve/moderada: + 8.9 % , p = 0.004; severo/crítico: + 12.4 %, p <0.003) y en el componente mental SF-36 (leve / moderado: +6.8 puntos, p = 0.062; severo/crítico: +16.7 puntos, -p <0,005). Discusión y conclusiones: un programa de ejercicio bien estructurado resulta en un beneficio en las esferas de capacidad aeróbica, volúmenes pulmonares y calidad de vida; en tal sentido, se recomienda ampliar las muestras poblacionales para poder aplicar nuestro protocolo a otros centros encargados de la rehabilitación de pacientes con COVID-19.


Introduction: COVID-19 disease can cause a wide variety of long-term health problems, such as impaired lung function, reduced exercise performance, and decreased quality of life. Our study aimed to investigate the efficacy, feasibility, and safety of pulmonary rehabilitation in patients with COVID-19 and to compare the results between patients with a mild/moderate and severe/critical course of the disease. Materials and Methods: Patients in the post-acute phase of a mild to critical course of COVID-19 admitted to a comprehensive pulmonary rehabilitation program were included in this prospective, observational cohort study. Various measures of exercise performance, 6-minute walk distance, lung function (forced vital capacity (FVC)), and quality of life (36-question short-form health survey (SF-36)) were assessed before and after. We include 43 patients in this study (20 with mild/moderate COVID and 23 with severe/critical COVID-19). Results: At admission, patients had reduced walking distance (mild: median 401 m, interquartile range (IQR) 335-467 m; severe: 108 m, 84-132 m), impaired FVC (mild: 72%, severe: 35%,) and a low SF-36 mental health score (mild: 52 points, severe: 32 points). This patients received sessions adjusted to their physical abilities, and in both subgroups the patients improved on the walking test of 6 min (mild/moderate: +54m, severe/critical: +117m, both p < 0.002), FVC (mild/moderate: +8.9%, p=0.004; severe/critical: +12.4%, p <0.003) and mental component SF-36 (mild / moderate: +6.8 points, p = 0.062; severe / critical: +16.7 points, -p <0.005). Discussion and Conclusions: A well-structured exercise program results in a benefit in the patients' spheres of aerobic capacity, lung volumes and quality of life, in this sense it is recommended to expand population samples to be able to apply our protocol to other centers in charge of the rehabilitation of COVID 19 patients.


Assuntos
Humanos , Exercício Físico , COVID-19 , Reabilitação , Pneumologia , Caminhada , Terapia por Exercício
11.
J Infect Dis ; 226(10): 1842-1851, 2022 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-36052609

RESUMO

Incidence of visceral leishmaniasis (VL) in the Indian subcontinent (ISC) has declined by more than 95% since initiation of the elimination program in 2005. As the ISC transitions to the postelimination surveillance phase, an accurate measurement of human-vector contact is needed to assure long-term success. To develop this tool, we identified PagSP02 and PagSP06 from saliva of Phlebotomus argentipes, the vector of Leishmania donovani in the ISC, as immunodominant proteins in humans. We also established the absence of cross-reactivity with Phlebotomus papatasi saliva, the only other human-biting sand fly in the ISC. Importantly, by combining recombinant rPagSP02 and rPagSP06 we achieved greater antibody recognition and specificity than single salivary proteins. The receiver operating characteristics curve for rPagSP02 + rPagSP06 predicts exposure to Ph. argentipes bites with 90% specificity and 87% sensitivity compared to negative control sera (P >.0001). Overall, rPagSP02 + rPagSP06 provides an effective surveillance tool for monitoring vector control efforts after VL elimination.


Assuntos
Leishmania donovani , Leishmaniose Visceral , Phlebotomus , Animais , Humanos , Leishmaniose Visceral/epidemiologia , Leishmania donovani/genética , Proteínas e Peptídeos Salivares , Biomarcadores , Índia/epidemiologia
12.
Polymers (Basel) ; 14(15)2022 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-35956574

RESUMO

A major limitation of the treatment of low-grade upper tract urothelial carcinoma is the difficulty of intracavitary instillation of adjuvant therapy. Therefore, the aim of this in vitro study was to develop and to assess a new design of biodegradable ureteral stent coated with a silk fibroin matrix for the controlled release of mitomycin C as a chemotherapeutic drug. For this purpose, we assessed the coating of a biodegradable ureteral stent, BraidStent®, with silk fibroin and subsequently loaded the polymeric matrix with two formulations of mitomycin to evaluate its degradation rate, the concentration of mitomycin released, and changes in the pH and the weight of the stent. Our results confirm that the silk fibroin matrix is able to coat the biodegradable stent and release mitomycin for between 6 and 12 h in the urinary environment. There was a significant delay in the degradation rate of silk fibroin and mitomycin-coated stents compared to bare biodegradable stents, from 6-7 weeks to 13-14 weeks. The present study has shown the feasibility of using mitomycin C-loaded silk fibroin for the coating of biodegradable urinary stents. The addition of mitomycin C to the coating of silk fibroin biodegradable stents could be an attractive approach for intracavitary instillation in the upper urinary tract.

13.
Methods Mol Biol ; 2510: 355-366, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35776336

RESUMO

The nervous system is formed by a complex network of neuronal connections. During development, neurons elongate their axons through highly stereotyped anatomical pathways to form precise connections. Defects in these mechanisms are related with neurological disorders. Previous studies have reported that inhibition of the P2X7 receptor, an ionotropic purinergic receptor, promotes axonal growth and branching in cultured neurons. However, little is known about the in vivo mechanism of axonal elongation regulated by P2X7. Here, we detailed a step-by-step method to perform in utero cortical electroporation and quantified the electroporated axons employing accessible and open-source image processing software. This effective surgical procedure manipulates in vivo the gene expression in a discrete population of callosal projection neuron. Thus, a better understanding of the involvement of P2X7 in the in vivo establishment of neuronal circuits might help to clarify the basic biology of several neurodevelopmental disorders and axonal regenerative processes.


Assuntos
Neurônios , Receptores Purinérgicos P2X7 , Axônios/fisiologia , Eletroporação/métodos , Neurônios/metabolismo , Receptores Purinérgicos P2X7/genética , Receptores Purinérgicos P2X7/metabolismo
14.
Acta méd. colomb ; 47(1): 58-61, ene.-mar. 2022. graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1374106

RESUMO

Resumen Introducción: la pandemia por COVID-19 ha generado un costo inexorable a los gobiernos y una mortalidad elevada en términos generales, el proceso de vacunación es la única estrategia efectiva en disminuir la morbimortalidad en general, sin embargo, dicha administración no está exenta de riesgos. Presentación del caso: presentamos el caso clínico de una paciente de género femenino de la séptima década, quien es vacunada contra el COVID-19 y tras cuatro días posteriores a la segunda dosis de vacuna anti COVID-19, comienza a presentar lesiones purpúricas que inician en miembros inferiores y ascienden progresivamente hasta el tronco asociado a artralgias intensas, dolor abdominal y náuseas. Es ingresada encontrándose recuentos plaquetarios menores a 10 mil plaquetas y se hace el diagnóstico de una púrpura trombocitopénica inmune asociada a la vacuna de AstraZeneca contra COVID-19, iniciándose terapia inmunosupresora específica. Discusión: el presente caso constituye la aparición de una púrpura trombocitopénica idiopática, patología poco frecuente con un amplio repertorio de eventos desencadenantes encontrándose las infecciones y reacciones vacunales dentro de los principales detonantes. La presente reacción vacunal es poco frecuente siendo lo anecdótico en específico la presencia de púrpura trombocitopénica inmune, hasta el momento son muy escasas las descripciones en la literatura sobre este tipo de reacción vacunal razón por la cual se decide recopilar y publicar el mismo mencionando la evidencia científica disponible más reciente sobre el tema. (Acta Med Colomb 2022; 47. DOI:https://doi.org/10.36104/amc.2022.2268).


Abstract Introduction: the COVID-19 pandemic has generated an inexorable cost for governments and an elevated mortality overall. Vaccination is the only effective strategy for decreasing overall morbidity and mortality; however, this vaccination is not without risks. Case presentation: we present the clinical case of a female patient in her seventies who was vaccinated against COVID-19 and four days after the second dose of the COVID-19 vaccine developed purpuric lesions beginning on her lower limbs and ascending progressively towards the trunk, associated with intense arthralgias, abdominal pain and nausea. She was admitted with platelet counts of less than 10,000, was diagnosed with immune thrombocytopenic purpura associated with the AstraZeneca COVID-19 vaccine, and was started on specific immunosuppressive therapy. Discussion: this is a case of idiopathic thrombocytopenic purpura, a rare pathology with a broad repertoire of triggering events, with infections and vaccine reactions among the main triggers. This vaccine reaction is rare, with the specific anecdotal point being the presence of immune thrombocytopenic purpura. To date, there are very few descriptions of this type of vaccine reaction in the literature, which is why we chose to compile and publish it, mentioning the most recent scientific evidence available on the subject. (Acta Med Colomb 2022; 47. DOI:https://doi.org/10.36104/amc.2022.2268).

15.
Neurobiol Dis ; 165: 105632, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35065251

RESUMO

Tauopathies are a family of neurodegenerative diseases characterized by the presence of abnormally hyperphosphorylated Tau protein. Several studies have proposed that increased extracellular Tau (eTau) leads to the spread of cerebral tauopathy. However, the molecular mechanisms underlying eTau-induced neurotoxicity remain unclear. Previous in vitro studies reported that the ecto-enzyme tissue-nonspecific alkaline phosphatase (TNAP) dephosphorylate eTau at different sites increasing its neurotoxicity. Here, we confirm TNAP protein upregulation in the brains of Alzheimer's patients and found a similar TNAP increase in Pick's disease patients and P301S mice, a well-characterized mouse model of tauopathies. Interestingly, the conditional overexpression of TNAP causes intracellular Tau hyperphosphorylation and aggregation in cells neighbouring those overexpressing the ectoenzyme. Conversely, the genetic disruption of TNAP reduced the dephosphorylation of eTau and decreased neuronal hyperactivity, brain atrophy, and hippocampal neuronal death in P301S mice. TNAP haploinsufficiency in P301S mice prevents the decreased anxiety-like behaviour, motor deficiency, and increased memory capacity and life expectancy. Similar results were observed by the in vivo pharmacological blunting of TNAP activity. This study provides the first in vivo evidence demonstrating that raised TNAP activity is critical for Tau-induced neurotoxicity and suggest that TNAP blockade may be a novel and efficient therapy to treat tauopathies.


Assuntos
Fosfatase Alcalina , Tauopatias , Fosfatase Alcalina/genética , Fosfatase Alcalina/metabolismo , Fosfatase Alcalina/uso terapêutico , Animais , Encéfalo/metabolismo , Modelos Animais de Doenças , Humanos , Expectativa de Vida , Camundongos , Camundongos Transgênicos , Tauopatias/metabolismo , Regulação para Cima , Proteínas tau/metabolismo
16.
mBio ; 13(1): e0235721, 2022 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-35012336

RESUMO

The single-celled parasite Trypanosoma brucei is transmitted by hematophagous tsetse flies. Life cycle progression from mammalian bloodstream form to tsetse midgut form and, subsequently, infective salivary gland form depends on complex developmental steps and migration within different fly tissues. As the parasite colonizes the glucose-poor insect midgut, ATP production is thought to depend on activation of mitochondrial amino acid catabolism via oxidative phosphorylation (OXPHOS). This process involves respiratory chain complexes and F1Fo-ATP synthase and requires protein subunits of these complexes that are encoded in the parasite's mitochondrial DNA (kDNA). Here, we show that progressive loss of kDNA-encoded functions correlates with a decreasing ability to initiate and complete development in the tsetse. First, parasites with a mutated F1Fo-ATP synthase with reduced capacity for OXPHOS can initiate differentiation from bloodstream to insect form, but they are unable to proliferate in vitro. Unexpectedly, these cells can still colonize the tsetse midgut. However, these parasites exhibit a motility defect and are severely impaired in colonizing or migrating to subsequent tsetse tissues. Second, parasites with a fully disrupted F1Fo-ATP synthase complex that is completely unable to produce ATP by OXPHOS can still differentiate to the first insect stage in vitro but die within a few days and cannot establish a midgut infection in vivo. Third, parasites lacking kDNA entirely can initiate differentiation but die soon after. Together, these scenarios suggest that efficient ATP production via OXPHOS is not essential for initial colonization of the tsetse vector but is required to power trypanosome migration within the fly. IMPORTANCE African trypanosomes cause disease in humans and their livestock and are transmitted by tsetse flies. The insect ingests these parasites with its blood meal, but to be transmitted to another mammal, the trypanosome must undergo complex development within the tsetse fly and migrate from the insect's gut to its salivary glands. Crucially, the parasite must switch from a sugar-based diet while in the mammal to a diet based primarily on amino acids when it develops in the insect. Here, we show that efficient energy production by an organelle called the mitochondrion is critical for the trypanosome's ability to swim and to migrate through the tsetse fly. Surprisingly, trypanosomes with impaired mitochondrial energy production are only mildly compromised in their ability to colonize the tsetse fly midgut. Our study adds a new perspective to the emerging view that infection of tsetse flies by trypanosomes is more complex than previously thought.


Assuntos
Parasitos , Trypanosoma brucei brucei , Trypanosoma , Tripanossomíase Africana , Moscas Tsé-Tsé , Animais , Humanos , Trypanosoma brucei brucei/genética , Moscas Tsé-Tsé/parasitologia , Parasitos/genética , DNA de Cinetoplasto/metabolismo , Fosforilação Oxidativa , Tripanossomíase Africana/parasitologia , Trypanosoma/metabolismo , Mamíferos/metabolismo
17.
Prog Neurobiol ; 208: 102173, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34516970

RESUMO

Tauopathies are neurodegenerative diseases characterized by the presence of aberrant intraneuronal aggregates of hyperphosphorylated Tau protein. Recent studies suggest that associated chronic neuroinflammation may contribute to the pathological Tau dissemination. However, the underlying molecular mechanisms remain unknown. Since purinergic P2X7 receptors (P2X7) can sense the rise of extracellular ATP levels associated with neuroinflammation, its involvement in neurodegeneration-associated inflammation was suggested. We found a P2X7 upregulation in patients diagnosed with different tauopathies and in a tauopathy mouse model, P301S mice. In vivo pharmacological or genetic blockade of P2X7 reverted microglial activation in P301S mice leading to a reduction in microglial migratory, secretory, and proliferative capacities, and promoting phagocytic function. Furthermore, it reduced the intraneuronal phosphorylated Tau levels in a GSK3-dependent way and increased extracellular phosphorylated Tau levels by reducing the expression of ectoenzyme TNAP. Accordingly, pharmacological or genetic blockade of P2X7 improved the cellular survival, motor and memory deficits and anxiolytic profile in P301S mice. Contrary, P2X7 overexpression caused a significant worsening of Tau-induced toxicity and aggravated the deteriorated motor and memory deficits in P301S mice. Our results indicate that P2X7 plays a deleterious role in tauopathies and suggest that its blockade may be a promising approach to treat Tauopathies.


Assuntos
Receptores Purinérgicos P2X7 , Tauopatias , Animais , Modelos Animais de Doenças , Quinase 3 da Glicogênio Sintase/metabolismo , Quinase 3 da Glicogênio Sintase/uso terapêutico , Humanos , Camundongos , Camundongos Transgênicos , Receptores Purinérgicos P2X7/uso terapêutico , Tauopatias/tratamento farmacológico , Tauopatias/metabolismo , Proteínas tau/metabolismo
18.
JACS Au ; 1(8): 1275-1287, 2021 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-34467365

RESUMO

All healthy humans have high levels of natural anti-α-galactosyl (α-Gal) antibodies (elicited by yet uncharacterized glycotopes), which may play important roles in immunoglycomics: (a) potential protection against certain parasitic and viral zoonotic infections; (b) targeting of α-Gal-engineered cancer cells; (c) aiding in tissue repair; and (d) serving as adjuvants in α-Gal-based vaccines. Patients with certain protozoan infections have specific anti-α-Gal antibodies, elicited against parasite-derived α-Gal-bearing glycotopes. These glycotopes, however, remain elusive except for the well-characterized glycotope Galα1,3Galß1,4GlcNAcα, expressed by Trypanosoma cruzi. The discovery of new parasitic glycotopes is greatly hindered by the enormous structural diversity of cell-surface glycans and the technical challenges of classical immunoglycomics, a top-down approach from cultivated parasites to isolated glycans. Here, we demonstrate that reversed immunoglycomics, a bottom-up approach, can identify parasite species-specific α-Gal-bearing glycotopes by probing synthetic oligosaccharides on neoglycoproteins. This method was tested here seeking to identify as-yet unknown glycotopes specific for Leishmania major, the causative agent of Old-World cutaneous leishmaniasis (OWCL). Neoglycoproteins decorated with synthetic α-Gal-containing oligosaccharides derived from L. major glycoinositolphospholipids served as antigens in a chemiluminescent enzyme-linked immunosorbent assay using sera from OWCL patients and noninfected individuals. Receiver-operating characteristic analysis identified Galpα1,3Galfß and Galpα1,3Galfß1,3Manpα glycotopes as diagnostic biomarkers for L. major-caused OWCL, which can distinguish with 100% specificity from heterologous diseases and L. tropica-caused OWCL. These glycotopes could prove useful in the development of rapid α-Gal-based diagnostics and vaccines for OWCL. Furthermore, this method could help unravel cryptic α-Gal-glycotopes of other protozoan parasites and enterobacteria that elicit the natural human anti-α-Gal antibodies.

19.
Transl Androl Urol ; 10(4): 1700-1710, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33968658

RESUMO

BACKGROUND: We assessed an antireflux biodegradable heparin-coated ureteral stent (BraidStent®-H) in an animal model comparative study after endoscopic treatment of ureteral strictures. METHODS: A total of 24 female pigs underwent initial endoscopic, nephrosonographic, and contrast fluoroscopy assessment of the urinary tract. Afterward, unilateral laparoscopic ureteral stricture model was performed. Three weeks later, the animals underwent laser endoureterotomy and were randomly assigned to Group-I, in which a double-pigtail stent was placed for 6 weeks, or Group-II, in which a BraidStent®-H was placed. Follow-up was carried out by ultrasonography, contrast fluoroscopy, ureteroscopy, urinalysis and bacteriuria assessment at 3, 6, 12 and 5 months. Finally, a pathological study of the urinary system was performed. RESULTS: There were no animals in Group-II with vesicoureteral reflux, with significance at 6 weeks with Group-I. Distal ureteral peristalsis was maintained in 50-75% in Group-II at 1-6 weeks. The 91.7% of stents in Group-II were degraded between 3-6 weeks, without obstructive fragments. Bacteriuria in Group II was 33.3-50% at 3 and 6 weeks. The global success rate by groups was 91.6% and 87.5% in groups I and II, respectively, with no statistical significance. CONCLUSIONS: BraidStent®-H has been shown to be as efficacious as current ureteral stents in the treatment of benign ureteral strictures following laser endoureterotomy. In addition, it reduces the morbidity associated with current stents and has a homogeneous and predictable degradation rate of about 6 weeks, with no obstructive fragments. Future studies are required to improve the antibacterial coating to reduce BraidStent®-H contamination in view of the results obtained with the heparin coating.

20.
Mol Psychiatry ; 26(11): 6411-6426, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34002021

RESUMO

Several psychiatric, neurologic and neurodegenerative disorders present increased brain ventricles volume, being hydrocephalus the disease with the major manifestation of ventriculomegaly caused by the accumulation of high amounts of cerebrospinal fluid (CSF). The molecules and pathomechanisms underlying cerebral ventricular enlargement are widely unknown. Kinase D interacting substrate of 220 kDa (KIDINS220) gene has been recently associated with schizophrenia and with a novel syndrome characterized by spastic paraplegia, intellectual disability, nystagmus and obesity (SINO syndrome), diseases frequently occurring with ventriculomegaly. Here we show that Kidins220, a transmembrane protein effector of various key neuronal signalling pathways, is a critical regulator of CSF homeostasis. We observe that both KIDINS220 and the water channel aquaporin-4 (AQP4) are markedly downregulated at the ventricular ependymal lining of idiopathic normal pressure hydrocephalus (iNPH) patients. We also find that Kidins220 deficient mice develop ventriculomegaly accompanied by water dyshomeostasis and loss of AQP4 in the brain ventricular ependymal layer and astrocytes. Kidins220 is a known cargo of the SNX27-retromer, a complex that redirects endocytosed plasma membrane proteins (cargos) back to the cell surface, thus avoiding their targeting to lysosomes for degradation. Mechanistically, we show that AQP4 is a novel cargo of the SNX27-retromer and that Kidins220 deficiency promotes a striking and unexpected downregulation of the SNX27-retromer that results in AQP4 lysosomal degradation. Accordingly, SNX27 silencing decreases AQP4 levels in wild-type astrocytes whereas SNX27 overexpression restores AQP4 content in Kidins220 deficient astrocytes. Together our data suggest that the KIDINS220-SNX27-retromer-AQP4 pathway is involved in human ventriculomegaly and open novel therapeutic perspectives.


Assuntos
Hidrocefalia , Animais , Aquaporina 4/genética , Aquaporina 4/metabolismo , Epêndima/metabolismo , Humanos , Hidrocefalia/genética , Hidrocefalia/metabolismo , Lisossomos/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Nexinas de Classificação/genética
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